Split tuptoaster.c into three separate files.
authorRobert Haas <[email protected]>
Wed, 15 May 2019 17:33:16 +0000 (13:33 -0400)
committerRobert Haas <[email protected]>
Thu, 1 Aug 2019 18:26:02 +0000 (14:26 -0400)
detoast.c/h contain functions required to detoast a datum, partially
or completely, plus a few other utility functions for examining the
size of toasted datums.

toast_internals.c/h contain functions that are used internally to the
TOAST subsystem but which (mostly) do not need to be accessed from
outside.

heaptoast.c/h contains code that is intrinsically specific to the
heap AM, either because it operates on HeapTuples or is based on the
layout of a heap page.

detoast.c and toast_internals.c are placed in
src/backend/access/common rather than src/backend/access/heap.  At
present, both files still have dependencies on the heap, but that will
be improved in a future commit.

36 files changed:
doc/src/sgml/storage.sgml
src/backend/access/common/Makefile
src/backend/access/common/detoast.c [new file with mode: 0644]
src/backend/access/common/heaptuple.c
src/backend/access/common/indextuple.c
src/backend/access/common/reloptions.c
src/backend/access/common/toast_internals.c [new file with mode: 0644]
src/backend/access/heap/Makefile
src/backend/access/heap/heapam.c
src/backend/access/heap/heapam_handler.c
src/backend/access/heap/heaptoast.c [new file with mode: 0644]
src/backend/access/heap/rewriteheap.c
src/backend/access/transam/xlog.c
src/backend/commands/analyze.c
src/backend/commands/cluster.c
src/backend/executor/execExprInterp.c
src/backend/executor/execTuples.c
src/backend/executor/tstoreReceiver.c
src/backend/replication/logical/reorderbuffer.c
src/backend/statistics/extended_stats.c
src/backend/storage/large_object/inv_api.c
src/backend/utils/adt/array_typanalyze.c
src/backend/utils/adt/datum.c
src/backend/utils/adt/expandedrecord.c
src/backend/utils/adt/rowtypes.c
src/backend/utils/adt/tsgistidx.c
src/backend/utils/adt/varchar.c
src/backend/utils/adt/varlena.c
src/backend/utils/cache/catcache.c
src/backend/utils/fmgr/fmgr.c
src/bin/pg_resetwal/pg_resetwal.c
src/include/access/detoast.h [new file with mode: 0644]
src/include/access/heaptoast.h [moved from src/include/access/tuptoaster.h with 57% similarity]
src/include/access/toast_internals.h [new file with mode: 0644]
src/pl/plpgsql/src/pl_exec.c
src/test/regress/regress.c

index 1047c77a635c7259c8409cc581af711df96eb8ed..78bd030346967443ad7fdc6470488c184076f879 100644 (file)
@@ -382,7 +382,7 @@ The oldest and most common type is a pointer to out-of-line data stored in
 a <firstterm><acronym>TOAST</acronym> table</firstterm> that is separate from, but
 associated with, the table containing the <acronym>TOAST</acronym> pointer datum
 itself.  These <firstterm>on-disk</firstterm> pointer datums are created by the
-<acronym>TOAST</acronym> management code (in <filename>access/heap/tuptoaster.c</filename>)
+<acronym>TOAST</acronym> management code (in <filename>access/common/toast_internals.c</filename>)
 when a tuple to be stored on disk is too large to be stored as-is.
 Further details appear in <xref linkend="storage-toast-ondisk"/>.
 Alternatively, a <acronym>TOAST</acronym> pointer datum can contain a pointer to
index d46950433771b5a38e5612a7ba3db8b1e189b1aa..9ac19d9f9e5d370b9107ee15a93ce9c002b9f8a8 100644 (file)
@@ -12,7 +12,8 @@ subdir = src/backend/access/common
 top_builddir = ../../../..
 include $(top_builddir)/src/Makefile.global
 
-OBJS = bufmask.o heaptuple.o indextuple.o printsimple.o printtup.o \
-       relation.o reloptions.o scankey.o session.o tupconvert.o tupdesc.o
+OBJS = bufmask.o detoast.o heaptuple.o indextuple.o printsimple.o \
+       printtup.o relation.o reloptions.o scankey.o session.o toast_internals.o \
+       tupconvert.o tupdesc.o
 
 include $(top_srcdir)/src/backend/common.mk
diff --git a/src/backend/access/common/detoast.c b/src/backend/access/common/detoast.c
new file mode 100644 (file)
index 0000000..57ca8af
--- /dev/null
@@ -0,0 +1,860 @@
+/*-------------------------------------------------------------------------
+ *
+ * detoast.c
+ *       Support routines for external and compressed storage of
+ *       variable size attributes.
+ *
+ * Copyright (c) 2000-2019, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *       src/backend/access/common/detoast.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "access/detoast.h"
+#include "access/genam.h"
+#include "access/heaptoast.h"
+#include "access/table.h"
+#include "access/toast_internals.h"
+#include "common/pg_lzcompress.h"
+#include "utils/expandeddatum.h"
+#include "utils/fmgroids.h"
+#include "utils/rel.h"
+
+static struct varlena *toast_fetch_datum(struct varlena *attr);
+static struct varlena *toast_fetch_datum_slice(struct varlena *attr,
+                                               int32 sliceoffset, int32 length);
+static struct varlena *toast_decompress_datum(struct varlena *attr);
+static struct varlena *toast_decompress_datum_slice(struct varlena *attr, int32 slicelength);
+
+/* ----------
+ * heap_tuple_fetch_attr -
+ *
+ *     Public entry point to get back a toasted value from
+ *     external source (possibly still in compressed format).
+ *
+ * This will return a datum that contains all the data internally, ie, not
+ * relying on external storage or memory, but it can still be compressed or
+ * have a short header.  Note some callers assume that if the input is an
+ * EXTERNAL datum, the result will be a pfree'able chunk.
+ * ----------
+ */
+struct varlena *
+heap_tuple_fetch_attr(struct varlena *attr)
+{
+       struct varlena *result;
+
+       if (VARATT_IS_EXTERNAL_ONDISK(attr))
+       {
+               /*
+                * This is an external stored plain value
+                */
+               result = toast_fetch_datum(attr);
+       }
+       else if (VARATT_IS_EXTERNAL_INDIRECT(attr))
+       {
+               /*
+                * This is an indirect pointer --- dereference it
+                */
+               struct varatt_indirect redirect;
+
+               VARATT_EXTERNAL_GET_POINTER(redirect, attr);
+               attr = (struct varlena *) redirect.pointer;
+
+               /* nested indirect Datums aren't allowed */
+               Assert(!VARATT_IS_EXTERNAL_INDIRECT(attr));
+
+               /* recurse if value is still external in some other way */
+               if (VARATT_IS_EXTERNAL(attr))
+                       return heap_tuple_fetch_attr(attr);
+
+               /*
+                * Copy into the caller's memory context, in case caller tries to
+                * pfree the result.
+                */
+               result = (struct varlena *) palloc(VARSIZE_ANY(attr));
+               memcpy(result, attr, VARSIZE_ANY(attr));
+       }
+       else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+       {
+               /*
+                * This is an expanded-object pointer --- get flat format
+                */
+               ExpandedObjectHeader *eoh;
+               Size            resultsize;
+
+               eoh = DatumGetEOHP(PointerGetDatum(attr));
+               resultsize = EOH_get_flat_size(eoh);
+               result = (struct varlena *) palloc(resultsize);
+               EOH_flatten_into(eoh, (void *) result, resultsize);
+       }
+       else
+       {
+               /*
+                * This is a plain value inside of the main tuple - why am I called?
+                */
+               result = attr;
+       }
+
+       return result;
+}
+
+
+/* ----------
+ * heap_tuple_untoast_attr -
+ *
+ *     Public entry point to get back a toasted value from compression
+ *     or external storage.  The result is always non-extended varlena form.
+ *
+ * Note some callers assume that if the input is an EXTERNAL or COMPRESSED
+ * datum, the result will be a pfree'able chunk.
+ * ----------
+ */
+struct varlena *
+heap_tuple_untoast_attr(struct varlena *attr)
+{
+       if (VARATT_IS_EXTERNAL_ONDISK(attr))
+       {
+               /*
+                * This is an externally stored datum --- fetch it back from there
+                */
+               attr = toast_fetch_datum(attr);
+               /* If it's compressed, decompress it */
+               if (VARATT_IS_COMPRESSED(attr))
+               {
+                       struct varlena *tmp = attr;
+
+                       attr = toast_decompress_datum(tmp);
+                       pfree(tmp);
+               }
+       }
+       else if (VARATT_IS_EXTERNAL_INDIRECT(attr))
+       {
+               /*
+                * This is an indirect pointer --- dereference it
+                */
+               struct varatt_indirect redirect;
+
+               VARATT_EXTERNAL_GET_POINTER(redirect, attr);
+               attr = (struct varlena *) redirect.pointer;
+
+               /* nested indirect Datums aren't allowed */
+               Assert(!VARATT_IS_EXTERNAL_INDIRECT(attr));
+
+               /* recurse in case value is still extended in some other way */
+               attr = heap_tuple_untoast_attr(attr);
+
+               /* if it isn't, we'd better copy it */
+               if (attr == (struct varlena *) redirect.pointer)
+               {
+                       struct varlena *result;
+
+                       result = (struct varlena *) palloc(VARSIZE_ANY(attr));
+                       memcpy(result, attr, VARSIZE_ANY(attr));
+                       attr = result;
+               }
+       }
+       else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+       {
+               /*
+                * This is an expanded-object pointer --- get flat format
+                */
+               attr = heap_tuple_fetch_attr(attr);
+               /* flatteners are not allowed to produce compressed/short output */
+               Assert(!VARATT_IS_EXTENDED(attr));
+       }
+       else if (VARATT_IS_COMPRESSED(attr))
+       {
+               /*
+                * This is a compressed value inside of the main tuple
+                */
+               attr = toast_decompress_datum(attr);
+       }
+       else if (VARATT_IS_SHORT(attr))
+       {
+               /*
+                * This is a short-header varlena --- convert to 4-byte header format
+                */
+               Size            data_size = VARSIZE_SHORT(attr) - VARHDRSZ_SHORT;
+               Size            new_size = data_size + VARHDRSZ;
+               struct varlena *new_attr;
+
+               new_attr = (struct varlena *) palloc(new_size);
+               SET_VARSIZE(new_attr, new_size);
+               memcpy(VARDATA(new_attr), VARDATA_SHORT(attr), data_size);
+               attr = new_attr;
+       }
+
+       return attr;
+}
+
+
+/* ----------
+ * heap_tuple_untoast_attr_slice -
+ *
+ *             Public entry point to get back part of a toasted value
+ *             from compression or external storage.
+ * ----------
+ */
+struct varlena *
+heap_tuple_untoast_attr_slice(struct varlena *attr,
+                                                         int32 sliceoffset, int32 slicelength)
+{
+       struct varlena *preslice;
+       struct varlena *result;
+       char       *attrdata;
+       int32           attrsize;
+
+       if (VARATT_IS_EXTERNAL_ONDISK(attr))
+       {
+               struct varatt_external toast_pointer;
+
+               VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+
+               /* fast path for non-compressed external datums */
+               if (!VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer))
+                       return toast_fetch_datum_slice(attr, sliceoffset, slicelength);
+
+               /* fetch it back (compressed marker will get set automatically) */
+               preslice = toast_fetch_datum(attr);
+       }
+       else if (VARATT_IS_EXTERNAL_INDIRECT(attr))
+       {
+               struct varatt_indirect redirect;
+
+               VARATT_EXTERNAL_GET_POINTER(redirect, attr);
+
+               /* nested indirect Datums aren't allowed */
+               Assert(!VARATT_IS_EXTERNAL_INDIRECT(redirect.pointer));
+
+               return heap_tuple_untoast_attr_slice(redirect.pointer,
+                                                                                        sliceoffset, slicelength);
+       }
+       else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+       {
+               /* pass it off to heap_tuple_fetch_attr to flatten */
+               preslice = heap_tuple_fetch_attr(attr);
+       }
+       else
+               preslice = attr;
+
+       Assert(!VARATT_IS_EXTERNAL(preslice));
+
+       if (VARATT_IS_COMPRESSED(preslice))
+       {
+               struct varlena *tmp = preslice;
+
+               /* Decompress enough to encompass the slice and the offset */
+               if (slicelength > 0 && sliceoffset >= 0)
+                       preslice = toast_decompress_datum_slice(tmp, slicelength + sliceoffset);
+               else
+                       preslice = toast_decompress_datum(tmp);
+
+               if (tmp != attr)
+                       pfree(tmp);
+       }
+
+       if (VARATT_IS_SHORT(preslice))
+       {
+               attrdata = VARDATA_SHORT(preslice);
+               attrsize = VARSIZE_SHORT(preslice) - VARHDRSZ_SHORT;
+       }
+       else
+       {
+               attrdata = VARDATA(preslice);
+               attrsize = VARSIZE(preslice) - VARHDRSZ;
+       }
+
+       /* slicing of datum for compressed cases and plain value */
+
+       if (sliceoffset >= attrsize)
+       {
+               sliceoffset = 0;
+               slicelength = 0;
+       }
+
+       if (((sliceoffset + slicelength) > attrsize) || slicelength < 0)
+               slicelength = attrsize - sliceoffset;
+
+       result = (struct varlena *) palloc(slicelength + VARHDRSZ);
+       SET_VARSIZE(result, slicelength + VARHDRSZ);
+
+       memcpy(VARDATA(result), attrdata + sliceoffset, slicelength);
+
+       if (preslice != attr)
+               pfree(preslice);
+
+       return result;
+}
+
+/* ----------
+ * toast_fetch_datum -
+ *
+ *     Reconstruct an in memory Datum from the chunks saved
+ *     in the toast relation
+ * ----------
+ */
+static struct varlena *
+toast_fetch_datum(struct varlena *attr)
+{
+       Relation        toastrel;
+       Relation   *toastidxs;
+       ScanKeyData toastkey;
+       SysScanDesc toastscan;
+       HeapTuple       ttup;
+       TupleDesc       toasttupDesc;
+       struct varlena *result;
+       struct varatt_external toast_pointer;
+       int32           ressize;
+       int32           residx,
+                               nextidx;
+       int32           numchunks;
+       Pointer         chunk;
+       bool            isnull;
+       char       *chunkdata;
+       int32           chunksize;
+       int                     num_indexes;
+       int                     validIndex;
+       SnapshotData SnapshotToast;
+
+       if (!VARATT_IS_EXTERNAL_ONDISK(attr))
+               elog(ERROR, "toast_fetch_datum shouldn't be called for non-ondisk datums");
+
+       /* Must copy to access aligned fields */
+       VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+
+       ressize = toast_pointer.va_extsize;
+       numchunks = ((ressize - 1) / TOAST_MAX_CHUNK_SIZE) + 1;
+
+       result = (struct varlena *) palloc(ressize + VARHDRSZ);
+
+       if (VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer))
+               SET_VARSIZE_COMPRESSED(result, ressize + VARHDRSZ);
+       else
+               SET_VARSIZE(result, ressize + VARHDRSZ);
+
+       /*
+        * Open the toast relation and its indexes
+        */
+       toastrel = table_open(toast_pointer.va_toastrelid, AccessShareLock);
+       toasttupDesc = toastrel->rd_att;
+
+       /* Look for the valid index of the toast relation */
+       validIndex = toast_open_indexes(toastrel,
+                                                                       AccessShareLock,
+                                                                       &toastidxs,
+                                                                       &num_indexes);
+
+       /*
+        * Setup a scan key to fetch from the index by va_valueid
+        */
+       ScanKeyInit(&toastkey,
+                               (AttrNumber) 1,
+                               BTEqualStrategyNumber, F_OIDEQ,
+                               ObjectIdGetDatum(toast_pointer.va_valueid));
+
+       /*
+        * Read the chunks by index
+        *
+        * Note that because the index is actually on (valueid, chunkidx) we will
+        * see the chunks in chunkidx order, even though we didn't explicitly ask
+        * for it.
+        */
+       nextidx = 0;
+
+       init_toast_snapshot(&SnapshotToast);
+       toastscan = systable_beginscan_ordered(toastrel, toastidxs[validIndex],
+                                                                                  &SnapshotToast, 1, &toastkey);
+       while ((ttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
+       {
+               /*
+                * Have a chunk, extract the sequence number and the data
+                */
+               residx = DatumGetInt32(fastgetattr(ttup, 2, toasttupDesc, &isnull));
+               Assert(!isnull);
+               chunk = DatumGetPointer(fastgetattr(ttup, 3, toasttupDesc, &isnull));
+               Assert(!isnull);
+               if (!VARATT_IS_EXTENDED(chunk))
+               {
+                       chunksize = VARSIZE(chunk) - VARHDRSZ;
+                       chunkdata = VARDATA(chunk);
+               }
+               else if (VARATT_IS_SHORT(chunk))
+               {
+                       /* could happen due to heap_form_tuple doing its thing */
+                       chunksize = VARSIZE_SHORT(chunk) - VARHDRSZ_SHORT;
+                       chunkdata = VARDATA_SHORT(chunk);
+               }
+               else
+               {
+                       /* should never happen */
+                       elog(ERROR, "found toasted toast chunk for toast value %u in %s",
+                                toast_pointer.va_valueid,
+                                RelationGetRelationName(toastrel));
+                       chunksize = 0;          /* keep compiler quiet */
+                       chunkdata = NULL;
+               }
+
+               /*
+                * Some checks on the data we've found
+                */
+               if (residx != nextidx)
+                       elog(ERROR, "unexpected chunk number %d (expected %d) for toast value %u in %s",
+                                residx, nextidx,
+                                toast_pointer.va_valueid,
+                                RelationGetRelationName(toastrel));
+               if (residx < numchunks - 1)
+               {
+                       if (chunksize != TOAST_MAX_CHUNK_SIZE)
+                               elog(ERROR, "unexpected chunk size %d (expected %d) in chunk %d of %d for toast value %u in %s",
+                                        chunksize, (int) TOAST_MAX_CHUNK_SIZE,
+                                        residx, numchunks,
+                                        toast_pointer.va_valueid,
+                                        RelationGetRelationName(toastrel));
+               }
+               else if (residx == numchunks - 1)
+               {
+                       if ((residx * TOAST_MAX_CHUNK_SIZE + chunksize) != ressize)
+                               elog(ERROR, "unexpected chunk size %d (expected %d) in final chunk %d for toast value %u in %s",
+                                        chunksize,
+                                        (int) (ressize - residx * TOAST_MAX_CHUNK_SIZE),
+                                        residx,
+                                        toast_pointer.va_valueid,
+                                        RelationGetRelationName(toastrel));
+               }
+               else
+                       elog(ERROR, "unexpected chunk number %d (out of range %d..%d) for toast value %u in %s",
+                                residx,
+                                0, numchunks - 1,
+                                toast_pointer.va_valueid,
+                                RelationGetRelationName(toastrel));
+
+               /*
+                * Copy the data into proper place in our result
+                */
+               memcpy(VARDATA(result) + residx * TOAST_MAX_CHUNK_SIZE,
+                          chunkdata,
+                          chunksize);
+
+               nextidx++;
+       }
+
+       /*
+        * Final checks that we successfully fetched the datum
+        */
+       if (nextidx != numchunks)
+               elog(ERROR, "missing chunk number %d for toast value %u in %s",
+                        nextidx,
+                        toast_pointer.va_valueid,
+                        RelationGetRelationName(toastrel));
+
+       /*
+        * End scan and close relations
+        */
+       systable_endscan_ordered(toastscan);
+       toast_close_indexes(toastidxs, num_indexes, AccessShareLock);
+       table_close(toastrel, AccessShareLock);
+
+       return result;
+}
+
+/* ----------
+ * toast_fetch_datum_slice -
+ *
+ *     Reconstruct a segment of a Datum from the chunks saved
+ *     in the toast relation
+ *
+ *     Note that this function only supports non-compressed external datums.
+ * ----------
+ */
+static struct varlena *
+toast_fetch_datum_slice(struct varlena *attr, int32 sliceoffset, int32 length)
+{
+       Relation        toastrel;
+       Relation   *toastidxs;
+       ScanKeyData toastkey[3];
+       int                     nscankeys;
+       SysScanDesc toastscan;
+       HeapTuple       ttup;
+       TupleDesc       toasttupDesc;
+       struct varlena *result;
+       struct varatt_external toast_pointer;
+       int32           attrsize;
+       int32           residx;
+       int32           nextidx;
+       int                     numchunks;
+       int                     startchunk;
+       int                     endchunk;
+       int32           startoffset;
+       int32           endoffset;
+       int                     totalchunks;
+       Pointer         chunk;
+       bool            isnull;
+       char       *chunkdata;
+       int32           chunksize;
+       int32           chcpystrt;
+       int32           chcpyend;
+       int                     num_indexes;
+       int                     validIndex;
+       SnapshotData SnapshotToast;
+
+       if (!VARATT_IS_EXTERNAL_ONDISK(attr))
+               elog(ERROR, "toast_fetch_datum_slice shouldn't be called for non-ondisk datums");
+
+       /* Must copy to access aligned fields */
+       VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+
+       /*
+        * It's nonsense to fetch slices of a compressed datum -- this isn't lo_*
+        * we can't return a compressed datum which is meaningful to toast later
+        */
+       Assert(!VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer));
+
+       attrsize = toast_pointer.va_extsize;
+       totalchunks = ((attrsize - 1) / TOAST_MAX_CHUNK_SIZE) + 1;
+
+       if (sliceoffset >= attrsize)
+       {
+               sliceoffset = 0;
+               length = 0;
+       }
+
+       if (((sliceoffset + length) > attrsize) || length < 0)
+               length = attrsize - sliceoffset;
+
+       result = (struct varlena *) palloc(length + VARHDRSZ);
+
+       SET_VARSIZE(result, length + VARHDRSZ);
+
+       if (length == 0)
+               return result;                  /* Can save a lot of work at this point! */
+
+       startchunk = sliceoffset / TOAST_MAX_CHUNK_SIZE;
+       endchunk = (sliceoffset + length - 1) / TOAST_MAX_CHUNK_SIZE;
+       numchunks = (endchunk - startchunk) + 1;
+
+       startoffset = sliceoffset % TOAST_MAX_CHUNK_SIZE;
+       endoffset = (sliceoffset + length - 1) % TOAST_MAX_CHUNK_SIZE;
+
+       /*
+        * Open the toast relation and its indexes
+        */
+       toastrel = table_open(toast_pointer.va_toastrelid, AccessShareLock);
+       toasttupDesc = toastrel->rd_att;
+
+       /* Look for the valid index of toast relation */
+       validIndex = toast_open_indexes(toastrel,
+                                                                       AccessShareLock,
+                                                                       &toastidxs,
+                                                                       &num_indexes);
+
+       /*
+        * Setup a scan key to fetch from the index. This is either two keys or
+        * three depending on the number of chunks.
+        */
+       ScanKeyInit(&toastkey[0],
+                               (AttrNumber) 1,
+                               BTEqualStrategyNumber, F_OIDEQ,
+                               ObjectIdGetDatum(toast_pointer.va_valueid));
+
+       /*
+        * Use equality condition for one chunk, a range condition otherwise:
+        */
+       if (numchunks == 1)
+       {
+               ScanKeyInit(&toastkey[1],
+                                       (AttrNumber) 2,
+                                       BTEqualStrategyNumber, F_INT4EQ,
+                                       Int32GetDatum(startchunk));
+               nscankeys = 2;
+       }
+       else
+       {
+               ScanKeyInit(&toastkey[1],
+                                       (AttrNumber) 2,
+                                       BTGreaterEqualStrategyNumber, F_INT4GE,
+                                       Int32GetDatum(startchunk));
+               ScanKeyInit(&toastkey[2],
+                                       (AttrNumber) 2,
+                                       BTLessEqualStrategyNumber, F_INT4LE,
+                                       Int32GetDatum(endchunk));
+               nscankeys = 3;
+       }
+
+       /*
+        * Read the chunks by index
+        *
+        * The index is on (valueid, chunkidx) so they will come in order
+        */
+       init_toast_snapshot(&SnapshotToast);
+       nextidx = startchunk;
+       toastscan = systable_beginscan_ordered(toastrel, toastidxs[validIndex],
+                                                                                  &SnapshotToast, nscankeys, toastkey);
+       while ((ttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
+       {
+               /*
+                * Have a chunk, extract the sequence number and the data
+                */
+               residx = DatumGetInt32(fastgetattr(ttup, 2, toasttupDesc, &isnull));
+               Assert(!isnull);
+               chunk = DatumGetPointer(fastgetattr(ttup, 3, toasttupDesc, &isnull));
+               Assert(!isnull);
+               if (!VARATT_IS_EXTENDED(chunk))
+               {
+                       chunksize = VARSIZE(chunk) - VARHDRSZ;
+                       chunkdata = VARDATA(chunk);
+               }
+               else if (VARATT_IS_SHORT(chunk))
+               {
+                       /* could happen due to heap_form_tuple doing its thing */
+                       chunksize = VARSIZE_SHORT(chunk) - VARHDRSZ_SHORT;
+                       chunkdata = VARDATA_SHORT(chunk);
+               }
+               else
+               {
+                       /* should never happen */
+                       elog(ERROR, "found toasted toast chunk for toast value %u in %s",
+                                toast_pointer.va_valueid,
+                                RelationGetRelationName(toastrel));
+                       chunksize = 0;          /* keep compiler quiet */
+                       chunkdata = NULL;
+               }
+
+               /*
+                * Some checks on the data we've found
+                */
+               if ((residx != nextidx) || (residx > endchunk) || (residx < startchunk))
+                       elog(ERROR, "unexpected chunk number %d (expected %d) for toast value %u in %s",
+                                residx, nextidx,
+                                toast_pointer.va_valueid,
+                                RelationGetRelationName(toastrel));
+               if (residx < totalchunks - 1)
+               {
+                       if (chunksize != TOAST_MAX_CHUNK_SIZE)
+                               elog(ERROR, "unexpected chunk size %d (expected %d) in chunk %d of %d for toast value %u in %s when fetching slice",
+                                        chunksize, (int) TOAST_MAX_CHUNK_SIZE,
+                                        residx, totalchunks,
+                                        toast_pointer.va_valueid,
+                                        RelationGetRelationName(toastrel));
+               }
+               else if (residx == totalchunks - 1)
+               {
+                       if ((residx * TOAST_MAX_CHUNK_SIZE + chunksize) != attrsize)
+                               elog(ERROR, "unexpected chunk size %d (expected %d) in final chunk %d for toast value %u in %s when fetching slice",
+                                        chunksize,
+                                        (int) (attrsize - residx * TOAST_MAX_CHUNK_SIZE),
+                                        residx,
+                                        toast_pointer.va_valueid,
+                                        RelationGetRelationName(toastrel));
+               }
+               else
+                       elog(ERROR, "unexpected chunk number %d (out of range %d..%d) for toast value %u in %s",
+                                residx,
+                                0, totalchunks - 1,
+                                toast_pointer.va_valueid,
+                                RelationGetRelationName(toastrel));
+
+               /*
+                * Copy the data into proper place in our result
+                */
+               chcpystrt = 0;
+               chcpyend = chunksize - 1;
+               if (residx == startchunk)
+                       chcpystrt = startoffset;
+               if (residx == endchunk)
+                       chcpyend = endoffset;
+
+               memcpy(VARDATA(result) +
+                          (residx * TOAST_MAX_CHUNK_SIZE - sliceoffset) + chcpystrt,
+                          chunkdata + chcpystrt,
+                          (chcpyend - chcpystrt) + 1);
+
+               nextidx++;
+       }
+
+       /*
+        * Final checks that we successfully fetched the datum
+        */
+       if (nextidx != (endchunk + 1))
+               elog(ERROR, "missing chunk number %d for toast value %u in %s",
+                        nextidx,
+                        toast_pointer.va_valueid,
+                        RelationGetRelationName(toastrel));
+
+       /*
+        * End scan and close relations
+        */
+       systable_endscan_ordered(toastscan);
+       toast_close_indexes(toastidxs, num_indexes, AccessShareLock);
+       table_close(toastrel, AccessShareLock);
+
+       return result;
+}
+
+/* ----------
+ * toast_decompress_datum -
+ *
+ * Decompress a compressed version of a varlena datum
+ */
+static struct varlena *
+toast_decompress_datum(struct varlena *attr)
+{
+       struct varlena *result;
+
+       Assert(VARATT_IS_COMPRESSED(attr));
+
+       result = (struct varlena *)
+               palloc(TOAST_COMPRESS_RAWSIZE(attr) + VARHDRSZ);
+       SET_VARSIZE(result, TOAST_COMPRESS_RAWSIZE(attr) + VARHDRSZ);
+
+       if (pglz_decompress(TOAST_COMPRESS_RAWDATA(attr),
+                                               VARSIZE(attr) - TOAST_COMPRESS_HDRSZ,
+                                               VARDATA(result),
+                                               TOAST_COMPRESS_RAWSIZE(attr), true) < 0)
+               elog(ERROR, "compressed data is corrupted");
+
+       return result;
+}
+
+
+/* ----------
+ * toast_decompress_datum_slice -
+ *
+ * Decompress the front of a compressed version of a varlena datum.
+ * offset handling happens in heap_tuple_untoast_attr_slice.
+ * Here we just decompress a slice from the front.
+ */
+static struct varlena *
+toast_decompress_datum_slice(struct varlena *attr, int32 slicelength)
+{
+       struct varlena *result;
+       int32 rawsize;
+
+       Assert(VARATT_IS_COMPRESSED(attr));
+
+       result = (struct varlena *) palloc(slicelength + VARHDRSZ);
+
+       rawsize = pglz_decompress(TOAST_COMPRESS_RAWDATA(attr),
+                                               VARSIZE(attr) - TOAST_COMPRESS_HDRSZ,
+                                               VARDATA(result),
+                                               slicelength, false);
+       if (rawsize < 0)
+               elog(ERROR, "compressed data is corrupted");
+
+       SET_VARSIZE(result, rawsize + VARHDRSZ);
+       return result;
+}
+
+/* ----------
+ * toast_raw_datum_size -
+ *
+ *     Return the raw (detoasted) size of a varlena datum
+ *     (including the VARHDRSZ header)
+ * ----------
+ */
+Size
+toast_raw_datum_size(Datum value)
+{
+       struct varlena *attr = (struct varlena *) DatumGetPointer(value);
+       Size            result;
+
+       if (VARATT_IS_EXTERNAL_ONDISK(attr))
+       {
+               /* va_rawsize is the size of the original datum -- including header */
+               struct varatt_external toast_pointer;
+
+               VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+               result = toast_pointer.va_rawsize;
+       }
+       else if (VARATT_IS_EXTERNAL_INDIRECT(attr))
+       {
+               struct varatt_indirect toast_pointer;
+
+               VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+
+               /* nested indirect Datums aren't allowed */
+               Assert(!VARATT_IS_EXTERNAL_INDIRECT(toast_pointer.pointer));
+
+               return toast_raw_datum_size(PointerGetDatum(toast_pointer.pointer));
+       }
+       else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+       {
+               result = EOH_get_flat_size(DatumGetEOHP(value));
+       }
+       else if (VARATT_IS_COMPRESSED(attr))
+       {
+               /* here, va_rawsize is just the payload size */
+               result = VARRAWSIZE_4B_C(attr) + VARHDRSZ;
+       }
+       else if (VARATT_IS_SHORT(attr))
+       {
+               /*
+                * we have to normalize the header length to VARHDRSZ or else the
+                * callers of this function will be confused.
+                */
+               result = VARSIZE_SHORT(attr) - VARHDRSZ_SHORT + VARHDRSZ;
+       }
+       else
+       {
+               /* plain untoasted datum */
+               result = VARSIZE(attr);
+       }
+       return result;
+}
+
+/* ----------
+ * toast_datum_size
+ *
+ *     Return the physical storage size (possibly compressed) of a varlena datum
+ * ----------
+ */
+Size
+toast_datum_size(Datum value)
+{
+       struct varlena *attr = (struct varlena *) DatumGetPointer(value);
+       Size            result;
+
+       if (VARATT_IS_EXTERNAL_ONDISK(attr))
+       {
+               /*
+                * Attribute is stored externally - return the extsize whether
+                * compressed or not.  We do not count the size of the toast pointer
+                * ... should we?
+                */
+               struct varatt_external toast_pointer;
+
+               VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+               result = toast_pointer.va_extsize;
+       }
+       else if (VARATT_IS_EXTERNAL_INDIRECT(attr))
+       {
+               struct varatt_indirect toast_pointer;
+
+               VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+
+               /* nested indirect Datums aren't allowed */
+               Assert(!VARATT_IS_EXTERNAL_INDIRECT(attr));
+
+               return toast_datum_size(PointerGetDatum(toast_pointer.pointer));
+       }
+       else if (VARATT_IS_EXTERNAL_EXPANDED(attr))
+       {
+               result = EOH_get_flat_size(DatumGetEOHP(value));
+       }
+       else if (VARATT_IS_SHORT(attr))
+       {
+               result = VARSIZE_SHORT(attr);
+       }
+       else
+       {
+               /*
+                * Attribute is stored inline either compressed or not, just calculate
+                * the size of the datum in either case.
+                */
+               result = VARSIZE(attr);
+       }
+       return result;
+}
index a48a6cd757f4442ef291ac013db6a623488a79ea..cc948958d7e3e2466312e4d17d0e111bcb382942 100644 (file)
@@ -18,7 +18,7 @@
  * (In performance-critical code paths we can use pg_detoast_datum_packed
  * and the appropriate access macros to avoid that overhead.)  Note that this
  * conversion is performed directly in heap_form_tuple, without invoking
- * tuptoaster.c.
+ * heaptoast.c.
  *
  * This change will break any code that assumes it needn't detoast values
  * that have been put into a tuple but never sent to disk.  Hopefully there
@@ -57,9 +57,9 @@
 
 #include "postgres.h"
 
+#include "access/heaptoast.h"
 #include "access/sysattr.h"
 #include "access/tupdesc_details.h"
-#include "access/tuptoaster.h"
 #include "executor/tuptable.h"
 #include "utils/expandeddatum.h"
 
index cb23be859de5872651fb7fe2048afff599042849..07586201b9da4dbad13b55053d294df959c5acf9 100644 (file)
 
 #include "postgres.h"
 
+#include "access/detoast.h"
+#include "access/heaptoast.h"
 #include "access/htup_details.h"
 #include "access/itup.h"
-#include "access/tuptoaster.h"
+#include "access/toast_internals.h"
 
+/*
+ * This enables de-toasting of index entries.  Needed until VACUUM is
+ * smart enough to rebuild indexes from scratch.
+ */
+#define TOAST_INDEX_HACK
 
 /* ----------------------------------------------------------------
  *                               index_ tuple interface routines
index 577302149931b53087c12333266ae941d26e1937..e1ec873600e5f6088e3941e5bbc8bc1f4d80acc1 100644 (file)
 
 #include "access/gist_private.h"
 #include "access/hash.h"
+#include "access/heaptoast.h"
 #include "access/htup_details.h"
 #include "access/nbtree.h"
 #include "access/reloptions.h"
 #include "access/spgist.h"
-#include "access/tuptoaster.h"
 #include "catalog/pg_type.h"
 #include "commands/defrem.h"
 #include "commands/tablespace.h"
diff --git a/src/backend/access/common/toast_internals.c b/src/backend/access/common/toast_internals.c
new file mode 100644 (file)
index 0000000..a971242
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+/*-------------------------------------------------------------------------
+ *
+ * toast_internals.c
+ *       Functions for internal use by the TOAST system.
+ *
+ * Copyright (c) 2000-2019, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *       src/backend/access/common/toast_internals.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "access/detoast.h"
+#include "access/genam.h"
+#include "access/heapam.h"
+#include "access/heaptoast.h"
+#include "access/table.h"
+#include "access/toast_internals.h"
+#include "access/xact.h"
+#include "catalog/catalog.h"
+#include "common/pg_lzcompress.h"
+#include "miscadmin.h"
+#include "utils/fmgroids.h"
+#include "utils/rel.h"
+#include "utils/snapmgr.h"
+
+static bool toastrel_valueid_exists(Relation toastrel, Oid valueid);
+static bool toastid_valueid_exists(Oid toastrelid, Oid valueid);
+
+/* ----------
+ * toast_compress_datum -
+ *
+ *     Create a compressed version of a varlena datum
+ *
+ *     If we fail (ie, compressed result is actually bigger than original)
+ *     then return NULL.  We must not use compressed data if it'd expand
+ *     the tuple!
+ *
+ *     We use VAR{SIZE,DATA}_ANY so we can handle short varlenas here without
+ *     copying them.  But we can't handle external or compressed datums.
+ * ----------
+ */
+Datum
+toast_compress_datum(Datum value)
+{
+       struct varlena *tmp;
+       int32           valsize = VARSIZE_ANY_EXHDR(DatumGetPointer(value));
+       int32           len;
+
+       Assert(!VARATT_IS_EXTERNAL(DatumGetPointer(value)));
+       Assert(!VARATT_IS_COMPRESSED(DatumGetPointer(value)));
+
+       /*
+        * No point in wasting a palloc cycle if value size is out of the allowed
+        * range for compression
+        */
+       if (valsize < PGLZ_strategy_default->min_input_size ||
+               valsize > PGLZ_strategy_default->max_input_size)
+               return PointerGetDatum(NULL);
+
+       tmp = (struct varlena *) palloc(PGLZ_MAX_OUTPUT(valsize) +
+                                                                       TOAST_COMPRESS_HDRSZ);
+
+       /*
+        * We recheck the actual size even if pglz_compress() reports success,
+        * because it might be satisfied with having saved as little as one byte
+        * in the compressed data --- which could turn into a net loss once you
+        * consider header and alignment padding.  Worst case, the compressed
+        * format might require three padding bytes (plus header, which is
+        * included in VARSIZE(tmp)), whereas the uncompressed format would take
+        * only one header byte and no padding if the value is short enough.  So
+        * we insist on a savings of more than 2 bytes to ensure we have a gain.
+        */
+       len = pglz_compress(VARDATA_ANY(DatumGetPointer(value)),
+                                               valsize,
+                                               TOAST_COMPRESS_RAWDATA(tmp),
+                                               PGLZ_strategy_default);
+       if (len >= 0 &&
+               len + TOAST_COMPRESS_HDRSZ < valsize - 2)
+       {
+               TOAST_COMPRESS_SET_RAWSIZE(tmp, valsize);
+               SET_VARSIZE_COMPRESSED(tmp, len + TOAST_COMPRESS_HDRSZ);
+               /* successful compression */
+               return PointerGetDatum(tmp);
+       }
+       else
+       {
+               /* incompressible data */
+               pfree(tmp);
+               return PointerGetDatum(NULL);
+       }
+}
+
+/* ----------
+ * toast_save_datum -
+ *
+ *     Save one single datum into the secondary relation and return
+ *     a Datum reference for it.
+ *
+ * rel: the main relation we're working with (not the toast rel!)
+ * value: datum to be pushed to toast storage
+ * oldexternal: if not NULL, toast pointer previously representing the datum
+ * options: options to be passed to heap_insert() for toast rows
+ * ----------
+ */
+Datum
+toast_save_datum(Relation rel, Datum value,
+                                struct varlena *oldexternal, int options)
+{
+       Relation        toastrel;
+       Relation   *toastidxs;
+       HeapTuple       toasttup;
+       TupleDesc       toasttupDesc;
+       Datum           t_values[3];
+       bool            t_isnull[3];
+       CommandId       mycid = GetCurrentCommandId(true);
+       struct varlena *result;
+       struct varatt_external toast_pointer;
+       union
+       {
+               struct varlena hdr;
+               /* this is to make the union big enough for a chunk: */
+               char            data[TOAST_MAX_CHUNK_SIZE + VARHDRSZ];
+               /* ensure union is aligned well enough: */
+               int32           align_it;
+       }                       chunk_data;
+       int32           chunk_size;
+       int32           chunk_seq = 0;
+       char       *data_p;
+       int32           data_todo;
+       Pointer         dval = DatumGetPointer(value);
+       int                     num_indexes;
+       int                     validIndex;
+
+       Assert(!VARATT_IS_EXTERNAL(value));
+
+       /*
+        * Open the toast relation and its indexes.  We can use the index to check
+        * uniqueness of the OID we assign to the toasted item, even though it has
+        * additional columns besides OID.
+        */
+       toastrel = table_open(rel->rd_rel->reltoastrelid, RowExclusiveLock);
+       toasttupDesc = toastrel->rd_att;
+
+       /* Open all the toast indexes and look for the valid one */
+       validIndex = toast_open_indexes(toastrel,
+                                                                       RowExclusiveLock,
+                                                                       &toastidxs,
+                                                                       &num_indexes);
+
+       /*
+        * Get the data pointer and length, and compute va_rawsize and va_extsize.
+        *
+        * va_rawsize is the size of the equivalent fully uncompressed datum, so
+        * we have to adjust for short headers.
+        *
+        * va_extsize is the actual size of the data payload in the toast records.
+        */
+       if (VARATT_IS_SHORT(dval))
+       {
+               data_p = VARDATA_SHORT(dval);
+               data_todo = VARSIZE_SHORT(dval) - VARHDRSZ_SHORT;
+               toast_pointer.va_rawsize = data_todo + VARHDRSZ;        /* as if not short */
+               toast_pointer.va_extsize = data_todo;
+       }
+       else if (VARATT_IS_COMPRESSED(dval))
+       {
+               data_p = VARDATA(dval);
+               data_todo = VARSIZE(dval) - VARHDRSZ;
+               /* rawsize in a compressed datum is just the size of the payload */
+               toast_pointer.va_rawsize = VARRAWSIZE_4B_C(dval) + VARHDRSZ;
+               toast_pointer.va_extsize = data_todo;
+               /* Assert that the numbers look like it's compressed */
+               Assert(VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer));
+       }
+       else
+       {
+               data_p = VARDATA(dval);
+               data_todo = VARSIZE(dval) - VARHDRSZ;
+               toast_pointer.va_rawsize = VARSIZE(dval);
+               toast_pointer.va_extsize = data_todo;
+       }
+
+       /*
+        * Insert the correct table OID into the result TOAST pointer.
+        *
+        * Normally this is the actual OID of the target toast table, but during
+        * table-rewriting operations such as CLUSTER, we have to insert the OID
+        * of the table's real permanent toast table instead.  rd_toastoid is set
+        * if we have to substitute such an OID.
+        */
+       if (OidIsValid(rel->rd_toastoid))
+               toast_pointer.va_toastrelid = rel->rd_toastoid;
+       else
+               toast_pointer.va_toastrelid = RelationGetRelid(toastrel);
+
+       /*
+        * Choose an OID to use as the value ID for this toast value.
+        *
+        * Normally we just choose an unused OID within the toast table.  But
+        * during table-rewriting operations where we are preserving an existing
+        * toast table OID, we want to preserve toast value OIDs too.  So, if
+        * rd_toastoid is set and we had a prior external value from that same
+        * toast table, re-use its value ID.  If we didn't have a prior external
+        * value (which is a corner case, but possible if the table's attstorage
+        * options have been changed), we have to pick a value ID that doesn't
+        * conflict with either new or existing toast value OIDs.
+        */
+       if (!OidIsValid(rel->rd_toastoid))
+       {
+               /* normal case: just choose an unused OID */
+               toast_pointer.va_valueid =
+                       GetNewOidWithIndex(toastrel,
+                                                          RelationGetRelid(toastidxs[validIndex]),
+                                                          (AttrNumber) 1);
+       }
+       else
+       {
+               /* rewrite case: check to see if value was in old toast table */
+               toast_pointer.va_valueid = InvalidOid;
+               if (oldexternal != NULL)
+               {
+                       struct varatt_external old_toast_pointer;
+
+                       Assert(VARATT_IS_EXTERNAL_ONDISK(oldexternal));
+                       /* Must copy to access aligned fields */
+                       VARATT_EXTERNAL_GET_POINTER(old_toast_pointer, oldexternal);
+                       if (old_toast_pointer.va_toastrelid == rel->rd_toastoid)
+                       {
+                               /* This value came from the old toast table; reuse its OID */
+                               toast_pointer.va_valueid = old_toast_pointer.va_valueid;
+
+                               /*
+                                * There is a corner case here: the table rewrite might have
+                                * to copy both live and recently-dead versions of a row, and
+                                * those versions could easily reference the same toast value.
+                                * When we copy the second or later version of such a row,
+                                * reusing the OID will mean we select an OID that's already
+                                * in the new toast table.  Check for that, and if so, just
+                                * fall through without writing the data again.
+                                *
+                                * While annoying and ugly-looking, this is a good thing
+                                * because it ensures that we wind up with only one copy of
+                                * the toast value when there is only one copy in the old
+                                * toast table.  Before we detected this case, we'd have made
+                                * multiple copies, wasting space; and what's worse, the
+                                * copies belonging to already-deleted heap tuples would not
+                                * be reclaimed by VACUUM.
+                                */
+                               if (toastrel_valueid_exists(toastrel,
+                                                                                       toast_pointer.va_valueid))
+                               {
+                                       /* Match, so short-circuit the data storage loop below */
+                                       data_todo = 0;
+                               }
+                       }
+               }
+               if (toast_pointer.va_valueid == InvalidOid)
+               {
+                       /*
+                        * new value; must choose an OID that doesn't conflict in either
+                        * old or new toast table
+                        */
+                       do
+                       {
+                               toast_pointer.va_valueid =
+                                       GetNewOidWithIndex(toastrel,
+                                                                          RelationGetRelid(toastidxs[validIndex]),
+                                                                          (AttrNumber) 1);
+                       } while (toastid_valueid_exists(rel->rd_toastoid,
+                                                                                       toast_pointer.va_valueid));
+               }
+       }
+
+       /*
+        * Initialize constant parts of the tuple data
+        */
+       t_values[0] = ObjectIdGetDatum(toast_pointer.va_valueid);
+       t_values[2] = PointerGetDatum(&chunk_data);
+       t_isnull[0] = false;
+       t_isnull[1] = false;
+       t_isnull[2] = false;
+
+       /*
+        * Split up the item into chunks
+        */
+       while (data_todo > 0)
+       {
+               int                     i;
+
+               CHECK_FOR_INTERRUPTS();
+
+               /*
+                * Calculate the size of this chunk
+                */
+               chunk_size = Min(TOAST_MAX_CHUNK_SIZE, data_todo);
+
+               /*
+                * Build a tuple and store it
+                */
+               t_values[1] = Int32GetDatum(chunk_seq++);
+               SET_VARSIZE(&chunk_data, chunk_size + VARHDRSZ);
+               memcpy(VARDATA(&chunk_data), data_p, chunk_size);
+               toasttup = heap_form_tuple(toasttupDesc, t_values, t_isnull);
+
+               heap_insert(toastrel, toasttup, mycid, options, NULL);
+
+               /*
+                * Create the index entry.  We cheat a little here by not using
+                * FormIndexDatum: this relies on the knowledge that the index columns
+                * are the same as the initial columns of the table for all the
+                * indexes.  We also cheat by not providing an IndexInfo: this is okay
+                * for now because btree doesn't need one, but we might have to be
+                * more honest someday.
+                *
+                * Note also that there had better not be any user-created index on
+                * the TOAST table, since we don't bother to update anything else.
+                */
+               for (i = 0; i < num_indexes; i++)
+               {
+                       /* Only index relations marked as ready can be updated */
+                       if (toastidxs[i]->rd_index->indisready)
+                               index_insert(toastidxs[i], t_values, t_isnull,
+                                                        &(toasttup->t_self),
+                                                        toastrel,
+                                                        toastidxs[i]->rd_index->indisunique ?
+                                                        UNIQUE_CHECK_YES : UNIQUE_CHECK_NO,
+                                                        NULL);
+               }
+
+               /*
+                * Free memory
+                */
+               heap_freetuple(toasttup);
+
+               /*
+                * Move on to next chunk
+                */
+               data_todo -= chunk_size;
+               data_p += chunk_size;
+       }
+
+       /*
+        * Done - close toast relation and its indexes
+        */
+       toast_close_indexes(toastidxs, num_indexes, RowExclusiveLock);
+       table_close(toastrel, RowExclusiveLock);
+
+       /*
+        * Create the TOAST pointer value that we'll return
+        */
+       result = (struct varlena *) palloc(TOAST_POINTER_SIZE);
+       SET_VARTAG_EXTERNAL(result, VARTAG_ONDISK);
+       memcpy(VARDATA_EXTERNAL(result), &toast_pointer, sizeof(toast_pointer));
+
+       return PointerGetDatum(result);
+}
+
+/* ----------
+ * toast_delete_datum -
+ *
+ *     Delete a single external stored value.
+ * ----------
+ */
+void
+toast_delete_datum(Relation rel, Datum value, bool is_speculative)
+{
+       struct varlena *attr = (struct varlena *) DatumGetPointer(value);
+       struct varatt_external toast_pointer;
+       Relation        toastrel;
+       Relation   *toastidxs;
+       ScanKeyData toastkey;
+       SysScanDesc toastscan;
+       HeapTuple       toasttup;
+       int                     num_indexes;
+       int                     validIndex;
+       SnapshotData SnapshotToast;
+
+       if (!VARATT_IS_EXTERNAL_ONDISK(attr))
+               return;
+
+       /* Must copy to access aligned fields */
+       VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr);
+
+       /*
+        * Open the toast relation and its indexes
+        */
+       toastrel = table_open(toast_pointer.va_toastrelid, RowExclusiveLock);
+
+       /* Fetch valid relation used for process */
+       validIndex = toast_open_indexes(toastrel,
+                                                                       RowExclusiveLock,
+                                                                       &toastidxs,
+                                                                       &num_indexes);
+
+       /*
+        * Setup a scan key to find chunks with matching va_valueid
+        */
+       ScanKeyInit(&toastkey,
+                               (AttrNumber) 1,
+                               BTEqualStrategyNumber, F_OIDEQ,
+                               ObjectIdGetDatum(toast_pointer.va_valueid));
+
+       /*
+        * Find all the chunks.  (We don't actually care whether we see them in
+        * sequence or not, but since we've already locked the index we might as
+        * well use systable_beginscan_ordered.)
+        */
+       init_toast_snapshot(&SnapshotToast);
+       toastscan = systable_beginscan_ordered(toastrel, toastidxs[validIndex],
+                                                                                  &SnapshotToast, 1, &toastkey);
+       while ((toasttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
+       {
+               /*
+                * Have a chunk, delete it
+                */
+               if (is_speculative)
+                       heap_abort_speculative(toastrel, &toasttup->t_self);
+               else
+                       simple_heap_delete(toastrel, &toasttup->t_self);
+       }
+
+       /*
+        * End scan and close relations
+        */
+       systable_endscan_ordered(toastscan);
+       toast_close_indexes(toastidxs, num_indexes, RowExclusiveLock);
+       table_close(toastrel, RowExclusiveLock);
+}
+
+/* ----------
+ * toastrel_valueid_exists -
+ *
+ *     Test whether a toast value with the given ID exists in the toast relation.
+ *     For safety, we consider a value to exist if there are either live or dead
+ *     toast rows with that ID; see notes for GetNewOidWithIndex().
+ * ----------
+ */
+static bool
+toastrel_valueid_exists(Relation toastrel, Oid valueid)
+{
+       bool            result = false;
+       ScanKeyData toastkey;
+       SysScanDesc toastscan;
+       int                     num_indexes;
+       int                     validIndex;
+       Relation   *toastidxs;
+
+       /* Fetch a valid index relation */
+       validIndex = toast_open_indexes(toastrel,
+                                                                       RowExclusiveLock,
+                                                                       &toastidxs,
+                                                                       &num_indexes);
+
+       /*
+        * Setup a scan key to find chunks with matching va_valueid
+        */
+       ScanKeyInit(&toastkey,
+                               (AttrNumber) 1,
+                               BTEqualStrategyNumber, F_OIDEQ,
+                               ObjectIdGetDatum(valueid));
+
+       /*
+        * Is there any such chunk?
+        */
+       toastscan = systable_beginscan(toastrel,
+                                                                  RelationGetRelid(toastidxs[validIndex]),
+                                                                  true, SnapshotAny, 1, &toastkey);
+
+       if (systable_getnext(toastscan) != NULL)
+               result = true;
+
+       systable_endscan(toastscan);
+
+       /* Clean up */
+       toast_close_indexes(toastidxs, num_indexes, RowExclusiveLock);
+
+       return result;
+}
+
+/* ----------
+ * toastid_valueid_exists -
+ *
+ *     As above, but work from toast rel's OID not an open relation
+ * ----------
+ */
+static bool
+toastid_valueid_exists(Oid toastrelid, Oid valueid)
+{
+       bool            result;
+       Relation        toastrel;
+
+       toastrel = table_open(toastrelid, AccessShareLock);
+
+       result = toastrel_valueid_exists(toastrel, valueid);
+
+       table_close(toastrel, AccessShareLock);
+
+       return result;
+}
+
+/* ----------
+ * toast_get_valid_index
+ *
+ *     Get OID of valid index associated to given toast relation. A toast
+ *     relation can have only one valid index at the same time.
+ */
+Oid
+toast_get_valid_index(Oid toastoid, LOCKMODE lock)
+{
+       int                     num_indexes;
+       int                     validIndex;
+       Oid                     validIndexOid;
+       Relation   *toastidxs;
+       Relation        toastrel;
+
+       /* Open the toast relation */
+       toastrel = table_open(toastoid, lock);
+
+       /* Look for the valid index of the toast relation */
+       validIndex = toast_open_indexes(toastrel,
+                                                                       lock,
+                                                                       &toastidxs,
+                                                                       &num_indexes);
+       validIndexOid = RelationGetRelid(toastidxs[validIndex]);
+
+       /* Close the toast relation and all its indexes */
+       toast_close_indexes(toastidxs, num_indexes, lock);
+       table_close(toastrel, lock);
+
+       return validIndexOid;
+}
+
+/* ----------
+ * toast_open_indexes
+ *
+ *     Get an array of the indexes associated to the given toast relation
+ *     and return as well the position of the valid index used by the toast
+ *     relation in this array. It is the responsibility of the caller of this
+ *     function to close the indexes as well as free them.
+ */
+int
+toast_open_indexes(Relation toastrel,
+                                  LOCKMODE lock,
+                                  Relation **toastidxs,
+                                  int *num_indexes)
+{
+       int                     i = 0;
+       int                     res = 0;
+       bool            found = false;
+       List       *indexlist;
+       ListCell   *lc;
+
+       /* Get index list of the toast relation */
+       indexlist = RelationGetIndexList(toastrel);
+       Assert(indexlist != NIL);
+
+       *num_indexes = list_length(indexlist);
+
+       /* Open all the index relations */
+       *toastidxs = (Relation *) palloc(*num_indexes * sizeof(Relation));
+       foreach(lc, indexlist)
+               (*toastidxs)[i++] = index_open(lfirst_oid(lc), lock);
+
+       /* Fetch the first valid index in list */
+       for (i = 0; i < *num_indexes; i++)
+       {
+               Relation        toastidx = (*toastidxs)[i];
+
+               if (toastidx->rd_index->indisvalid)
+               {
+                       res = i;
+                       found = true;
+                       break;
+               }
+       }
+
+       /*
+        * Free index list, not necessary anymore as relations are opened and a
+        * valid index has been found.
+        */
+       list_free(indexlist);
+
+       /*
+        * The toast relation should have one valid index, so something is going
+        * wrong if there is nothing.
+        */
+       if (!found)
+               elog(ERROR, "no valid index found for toast relation with Oid %u",
+                        RelationGetRelid(toastrel));
+
+       return res;
+}
+
+/* ----------
+ * toast_close_indexes
+ *
+ *     Close an array of indexes for a toast relation and free it. This should
+ *     be called for a set of indexes opened previously with toast_open_indexes.
+ */
+void
+toast_close_indexes(Relation *toastidxs, int num_indexes, LOCKMODE lock)
+{
+       int                     i;
+
+       /* Close relations and clean up things */
+       for (i = 0; i < num_indexes; i++)
+               index_close(toastidxs[i], lock);
+       pfree(toastidxs);
+}
+
+/* ----------
+ * init_toast_snapshot
+ *
+ *     Initialize an appropriate TOAST snapshot.  We must use an MVCC snapshot
+ *     to initialize the TOAST snapshot; since we don't know which one to use,
+ *     just use the oldest one.  This is safe: at worst, we will get a "snapshot
+ *     too old" error that might have been avoided otherwise.
+ */
+void
+init_toast_snapshot(Snapshot toast_snapshot)
+{
+       Snapshot        snapshot = GetOldestSnapshot();
+
+       if (snapshot == NULL)
+               elog(ERROR, "no known snapshots");
+
+       InitToastSnapshot(*toast_snapshot, snapshot->lsn, snapshot->whenTaken);
+}
index b2a017249b8b2ab6797a83da27b055498af35a2d..38497b09c07f7fcc8920084ebd15a0ee68d0edff 100644 (file)
@@ -13,6 +13,6 @@ top_builddir = ../../../..
 include $(top_builddir)/src/Makefile.global
 
 OBJS = heapam.o heapam_handler.o heapam_visibility.o hio.o pruneheap.o rewriteheap.o \
-       syncscan.o tuptoaster.o vacuumlazy.o visibilitymap.o
+       syncscan.o heaptoast.o vacuumlazy.o visibilitymap.o
 
 include $(top_srcdir)/src/backend/common.mk
index d768b9b061cd976eb9aecb3c760131c091a13e99..ce141b734bbf2e0eb009a3763ab6508bb9d0f4a1 100644 (file)
@@ -36,6 +36,7 @@
 #include "access/genam.h"
 #include "access/heapam.h"
 #include "access/heapam_xlog.h"
+#include "access/heaptoast.h"
 #include "access/hio.h"
 #include "access/multixact.h"
 #include "access/parallel.h"
@@ -43,7 +44,6 @@
 #include "access/sysattr.h"
 #include "access/tableam.h"
 #include "access/transam.h"
-#include "access/tuptoaster.h"
 #include "access/valid.h"
 #include "access/visibilitymap.h"
 #include "access/xact.h"
index 09bc6fe98a723819d64cbbabaf8037604ca3b86f..9f411161cb3e04b71c6d286dfe0544d41aa25eb9 100644 (file)
 
 #include "access/genam.h"
 #include "access/heapam.h"
+#include "access/heaptoast.h"
 #include "access/multixact.h"
 #include "access/rewriteheap.h"
 #include "access/tableam.h"
 #include "access/tsmapi.h"
-#include "access/tuptoaster.h"
 #include "access/xact.h"
 #include "catalog/catalog.h"
 #include "catalog/index.h"
diff --git a/src/backend/access/heap/heaptoast.c b/src/backend/access/heap/heaptoast.c
new file mode 100644 (file)
index 0000000..5d105e3
--- /dev/null
@@ -0,0 +1,917 @@
+/*-------------------------------------------------------------------------
+ *
+ * heaptoast.c
+ *       Heap-specific definitions for external and compressed storage
+ *       of variable size attributes.
+ *
+ * Copyright (c) 2000-2019, PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ *       src/backend/access/heap/heaptoast.c
+ *
+ *
+ * INTERFACE ROUTINES
+ *             toast_insert_or_update -
+ *                     Try to make a given tuple fit into one page by compressing
+ *                     or moving off attributes
+ *
+ *             toast_delete -
+ *                     Reclaim toast storage when a tuple is deleted
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "access/detoast.h"
+#include "access/heapam.h"
+#include "access/heaptoast.h"
+#include "access/toast_internals.h"
+
+
+/* ----------
+ * toast_delete -
+ *
+ *     Cascaded delete toast-entries on DELETE
+ * ----------
+ */
+void
+toast_delete(Relation rel, HeapTuple oldtup, bool is_speculative)
+{
+       TupleDesc       tupleDesc;
+       int                     numAttrs;
+       int                     i;
+       Datum           toast_values[MaxHeapAttributeNumber];
+       bool            toast_isnull[MaxHeapAttributeNumber];
+
+       /*
+        * We should only ever be called for tuples of plain relations or
+        * materialized views --- recursing on a toast rel is bad news.
+        */
+       Assert(rel->rd_rel->relkind == RELKIND_RELATION ||
+                  rel->rd_rel->relkind == RELKIND_MATVIEW);
+
+       /*
+        * Get the tuple descriptor and break down the tuple into fields.
+        *
+        * NOTE: it's debatable whether to use heap_deform_tuple() here or just
+        * heap_getattr() only the varlena columns.  The latter could win if there
+        * are few varlena columns and many non-varlena ones. However,
+        * heap_deform_tuple costs only O(N) while the heap_getattr way would cost
+        * O(N^2) if there are many varlena columns, so it seems better to err on
+        * the side of linear cost.  (We won't even be here unless there's at
+        * least one varlena column, by the way.)
+        */
+       tupleDesc = rel->rd_att;
+       numAttrs = tupleDesc->natts;
+
+       Assert(numAttrs <= MaxHeapAttributeNumber);
+       heap_deform_tuple(oldtup, tupleDesc, toast_values, toast_isnull);
+
+       /*
+        * Check for external stored attributes and delete them from the secondary
+        * relation.
+        */
+       for (i = 0; i < numAttrs; i++)
+       {
+               if (TupleDescAttr(tupleDesc, i)->attlen == -1)
+               {
+                       Datum           value = toast_values[i];
+
+                       if (toast_isnull[i])
+                               continue;
+                       else if (VARATT_IS_EXTERNAL_ONDISK(PointerGetDatum(value)))
+                               toast_delete_datum(rel, value, is_speculative);
+               }
+       }
+}
+
+
+/* ----------
+ * toast_insert_or_update -
+ *
+ *     Delete no-longer-used toast-entries and create new ones to
+ *     make the new tuple fit on INSERT or UPDATE
+ *
+ * Inputs:
+ *     newtup: the candidate new tuple to be inserted
+ *     oldtup: the old row version for UPDATE, or NULL for INSERT
+ *     options: options to be passed to heap_insert() for toast rows
+ * Result:
+ *     either newtup if no toasting is needed, or a palloc'd modified tuple
+ *     that is what should actually get stored
+ *
+ * NOTE: neither newtup nor oldtup will be modified.  This is a change
+ * from the pre-8.1 API of this routine.
+ * ----------
+ */
+HeapTuple
+toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup,
+                                          int options)
+{
+       HeapTuple       result_tuple;
+       TupleDesc       tupleDesc;
+       int                     numAttrs;
+       int                     i;
+
+       bool            need_change = false;
+       bool            need_free = false;
+       bool            need_delold = false;
+       bool            has_nulls = false;
+
+       Size            maxDataLen;
+       Size            hoff;
+
+       char            toast_action[MaxHeapAttributeNumber];
+       bool            toast_isnull[MaxHeapAttributeNumber];
+       bool            toast_oldisnull[MaxHeapAttributeNumber];
+       Datum           toast_values[MaxHeapAttributeNumber];
+       Datum           toast_oldvalues[MaxHeapAttributeNumber];
+       struct varlena *toast_oldexternal[MaxHeapAttributeNumber];
+       int32           toast_sizes[MaxHeapAttributeNumber];
+       bool            toast_free[MaxHeapAttributeNumber];
+       bool            toast_delold[MaxHeapAttributeNumber];
+
+       /*
+        * Ignore the INSERT_SPECULATIVE option. Speculative insertions/super
+        * deletions just normally insert/delete the toast values. It seems
+        * easiest to deal with that here, instead on, potentially, multiple
+        * callers.
+        */
+       options &= ~HEAP_INSERT_SPECULATIVE;
+
+       /*
+        * We should only ever be called for tuples of plain relations or
+        * materialized views --- recursing on a toast rel is bad news.
+        */
+       Assert(rel->rd_rel->relkind == RELKIND_RELATION ||
+                  rel->rd_rel->relkind == RELKIND_MATVIEW);
+
+       /*
+        * Get the tuple descriptor and break down the tuple(s) into fields.
+        */
+       tupleDesc = rel->rd_att;
+       numAttrs = tupleDesc->natts;
+
+       Assert(numAttrs <= MaxHeapAttributeNumber);
+       heap_deform_tuple(newtup, tupleDesc, toast_values, toast_isnull);
+       if (oldtup != NULL)
+               heap_deform_tuple(oldtup, tupleDesc, toast_oldvalues, toast_oldisnull);
+
+       /* ----------
+        * Then collect information about the values given
+        *
+        * NOTE: toast_action[i] can have these values:
+        *              ' '             default handling
+        *              'p'             already processed --- don't touch it
+        *              'x'             incompressible, but OK to move off
+        *
+        * NOTE: toast_sizes[i] is only made valid for varlena attributes with
+        *              toast_action[i] different from 'p'.
+        * ----------
+        */
+       memset(toast_action, ' ', numAttrs * sizeof(char));
+       memset(toast_oldexternal, 0, numAttrs * sizeof(struct varlena *));
+       memset(toast_free, 0, numAttrs * sizeof(bool));
+       memset(toast_delold, 0, numAttrs * sizeof(bool));
+
+       for (i = 0; i < numAttrs; i++)
+       {
+               Form_pg_attribute att = TupleDescAttr(tupleDesc, i);
+               struct varlena *old_value;
+               struct varlena *new_value;
+
+               if (oldtup != NULL)
+               {
+                       /*
+                        * For UPDATE get the old and new values of this attribute
+                        */
+                       old_value = (struct varlena *) DatumGetPointer(toast_oldvalues[i]);
+                       new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
+
+                       /*
+                        * If the old value is stored on disk, check if it has changed so
+                        * we have to delete it later.
+                        */
+                       if (att->attlen == -1 && !toast_oldisnull[i] &&
+                               VARATT_IS_EXTERNAL_ONDISK(old_value))
+                       {
+                               if (toast_isnull[i] || !VARATT_IS_EXTERNAL_ONDISK(new_value) ||
+                                       memcmp((char *) old_value, (char *) new_value,
+                                                  VARSIZE_EXTERNAL(old_value)) != 0)
+                               {
+                                       /*
+                                        * The old external stored value isn't needed any more
+                                        * after the update
+                                        */
+                                       toast_delold[i] = true;
+                                       need_delold = true;
+                               }
+                               else
+                               {
+                                       /*
+                                        * This attribute isn't changed by this update so we reuse
+                                        * the original reference to the old value in the new
+                                        * tuple.
+                                        */
+                                       toast_action[i] = 'p';
+                                       continue;
+                               }
+                       }
+               }
+               else
+               {
+                       /*
+                        * For INSERT simply get the new value
+                        */
+                       new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
+               }
+
+               /*
+                * Handle NULL attributes
+                */
+               if (toast_isnull[i])
+               {
+                       toast_action[i] = 'p';
+                       has_nulls = true;
+                       continue;
+               }
+
+               /*
+                * Now look at varlena attributes
+                */
+               if (att->attlen == -1)
+               {
+                       /*
+                        * If the table's attribute says PLAIN always, force it so.
+                        */
+                       if (att->attstorage == 'p')
+                               toast_action[i] = 'p';
+
+                       /*
+                        * We took care of UPDATE above, so any external value we find
+                        * still in the tuple must be someone else's that we cannot reuse
+                        * (this includes the case of an out-of-line in-memory datum).
+                        * Fetch it back (without decompression, unless we are forcing
+                        * PLAIN storage).  If necessary, we'll push it out as a new
+                        * external value below.
+                        */
+                       if (VARATT_IS_EXTERNAL(new_value))
+                       {
+                               toast_oldexternal[i] = new_value;
+                               if (att->attstorage == 'p')
+                                       new_value = heap_tuple_untoast_attr(new_value);
+                               else
+                                       new_value = heap_tuple_fetch_attr(new_value);
+                               toast_values[i] = PointerGetDatum(new_value);
+                               toast_free[i] = true;
+                               need_change = true;
+                               need_free = true;
+                       }
+
+                       /*
+                        * Remember the size of this attribute
+                        */
+                       toast_sizes[i] = VARSIZE_ANY(new_value);
+               }
+               else
+               {
+                       /*
+                        * Not a varlena attribute, plain storage always
+                        */
+                       toast_action[i] = 'p';
+               }
+       }
+
+       /* ----------
+        * Compress and/or save external until data fits into target length
+        *
+        *      1: Inline compress attributes with attstorage 'x', and store very
+        *         large attributes with attstorage 'x' or 'e' external immediately
+        *      2: Store attributes with attstorage 'x' or 'e' external
+        *      3: Inline compress attributes with attstorage 'm'
+        *      4: Store attributes with attstorage 'm' external
+        * ----------
+        */
+
+       /* compute header overhead --- this should match heap_form_tuple() */
+       hoff = SizeofHeapTupleHeader;
+       if (has_nulls)
+               hoff += BITMAPLEN(numAttrs);
+       hoff = MAXALIGN(hoff);
+       /* now convert to a limit on the tuple data size */
+       maxDataLen = RelationGetToastTupleTarget(rel, TOAST_TUPLE_TARGET) - hoff;
+
+       /*
+        * Look for attributes with attstorage 'x' to compress.  Also find large
+        * attributes with attstorage 'x' or 'e', and store them external.
+        */
+       while (heap_compute_data_size(tupleDesc,
+                                                                 toast_values, toast_isnull) > maxDataLen)
+       {
+               int                     biggest_attno = -1;
+               int32           biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
+               Datum           old_value;
+               Datum           new_value;
+
+               /*
+                * Search for the biggest yet unprocessed internal attribute
+                */
+               for (i = 0; i < numAttrs; i++)
+               {
+                       Form_pg_attribute att = TupleDescAttr(tupleDesc, i);
+
+                       if (toast_action[i] != ' ')
+                               continue;
+                       if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
+                               continue;               /* can't happen, toast_action would be 'p' */
+                       if (VARATT_IS_COMPRESSED(DatumGetPointer(toast_values[i])))
+                               continue;
+                       if (att->attstorage != 'x' && att->attstorage != 'e')
+                               continue;
+                       if (toast_sizes[i] > biggest_size)
+                       {
+                               biggest_attno = i;
+                               biggest_size = toast_sizes[i];
+                       }
+               }
+
+               if (biggest_attno < 0)
+                       break;
+
+               /*
+                * Attempt to compress it inline, if it has attstorage 'x'
+                */
+               i = biggest_attno;
+               if (TupleDescAttr(tupleDesc, i)->attstorage == 'x')
+               {
+                       old_value = toast_values[i];
+                       new_value = toast_compress_datum(old_value);
+
+                       if (DatumGetPointer(new_value) != NULL)
+                       {
+                               /* successful compression */
+                               if (toast_free[i])
+                                       pfree(DatumGetPointer(old_value));
+                               toast_values[i] = new_value;
+                               toast_free[i] = true;
+                               toast_sizes[i] = VARSIZE(DatumGetPointer(toast_values[i]));
+                               need_change = true;
+                               need_free = true;
+                       }
+                       else
+                       {
+                               /* incompressible, ignore on subsequent compression passes */
+                               toast_action[i] = 'x';
+                       }
+               }
+               else
+               {
+                       /* has attstorage 'e', ignore on subsequent compression passes */
+                       toast_action[i] = 'x';
+               }
+
+               /*
+                * If this value is by itself more than maxDataLen (after compression
+                * if any), push it out to the toast table immediately, if possible.
+                * This avoids uselessly compressing other fields in the common case
+                * where we have one long field and several short ones.
+                *
+                * XXX maybe the threshold should be less than maxDataLen?
+                */
+               if (toast_sizes[i] > maxDataLen &&
+                       rel->rd_rel->reltoastrelid != InvalidOid)
+               {
+                       old_value = toast_values[i];
+                       toast_action[i] = 'p';
+                       toast_values[i] = toast_save_datum(rel, toast_values[i],
+                                                                                          toast_oldexternal[i], options);
+                       if (toast_free[i])
+                               pfree(DatumGetPointer(old_value));
+                       toast_free[i] = true;
+                       need_change = true;
+                       need_free = true;
+               }
+       }
+
+       /*
+        * Second we look for attributes of attstorage 'x' or 'e' that are still
+        * inline.  But skip this if there's no toast table to push them to.
+        */
+       while (heap_compute_data_size(tupleDesc,
+                                                                 toast_values, toast_isnull) > maxDataLen &&
+                  rel->rd_rel->reltoastrelid != InvalidOid)
+       {
+               int                     biggest_attno = -1;
+               int32           biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
+               Datum           old_value;
+
+               /*------
+                * Search for the biggest yet inlined attribute with
+                * attstorage equals 'x' or 'e'
+                *------
+                */
+               for (i = 0; i < numAttrs; i++)
+               {
+                       Form_pg_attribute att = TupleDescAttr(tupleDesc, i);
+
+                       if (toast_action[i] == 'p')
+                               continue;
+                       if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
+                               continue;               /* can't happen, toast_action would be 'p' */
+                       if (att->attstorage != 'x' && att->attstorage != 'e')
+                               continue;
+                       if (toast_sizes[i] > biggest_size)
+                       {
+                               biggest_attno = i;
+                               biggest_size = toast_sizes[i];
+                       }
+               }
+
+               if (biggest_attno < 0)
+                       break;
+
+               /*
+                * Store this external
+                */
+               i = biggest_attno;
+               old_value = toast_values[i];
+               toast_action[i] = 'p';
+               toast_values[i] = toast_save_datum(rel, toast_values[i],
+                                                                                  toast_oldexternal[i], options);
+               if (toast_free[i])
+                       pfree(DatumGetPointer(old_value));
+               toast_free[i] = true;
+
+               need_change = true;
+               need_free = true;
+       }
+
+       /*
+        * Round 3 - this time we take attributes with storage 'm' into
+        * compression
+        */
+       while (heap_compute_data_size(tupleDesc,
+                                                                 toast_values, toast_isnull) > maxDataLen)
+       {
+               int                     biggest_attno = -1;
+               int32           biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
+               Datum           old_value;
+               Datum           new_value;
+
+               /*
+                * Search for the biggest yet uncompressed internal attribute
+                */
+               for (i = 0; i < numAttrs; i++)
+               {
+                       if (toast_action[i] != ' ')
+                               continue;
+                       if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
+                               continue;               /* can't happen, toast_action would be 'p' */
+                       if (VARATT_IS_COMPRESSED(DatumGetPointer(toast_values[i])))
+                               continue;
+                       if (TupleDescAttr(tupleDesc, i)->attstorage != 'm')
+                               continue;
+                       if (toast_sizes[i] > biggest_size)
+                       {
+                               biggest_attno = i;
+                               biggest_size = toast_sizes[i];
+                       }
+               }
+
+               if (biggest_attno < 0)
+                       break;
+
+               /*
+                * Attempt to compress it inline
+                */
+               i = biggest_attno;
+               old_value = toast_values[i];
+               new_value = toast_compress_datum(old_value);
+
+               if (DatumGetPointer(new_value) != NULL)
+               {
+                       /* successful compression */
+                       if (toast_free[i])
+                               pfree(DatumGetPointer(old_value));
+                       toast_values[i] = new_value;
+                       toast_free[i] = true;
+                       toast_sizes[i] = VARSIZE(DatumGetPointer(toast_values[i]));
+                       need_change = true;
+                       need_free = true;
+               }
+               else
+               {
+                       /* incompressible, ignore on subsequent compression passes */
+                       toast_action[i] = 'x';
+               }
+       }
+
+       /*
+        * Finally we store attributes of type 'm' externally.  At this point we
+        * increase the target tuple size, so that 'm' attributes aren't stored
+        * externally unless really necessary.
+        */
+       maxDataLen = TOAST_TUPLE_TARGET_MAIN - hoff;
+
+       while (heap_compute_data_size(tupleDesc,
+                                                                 toast_values, toast_isnull) > maxDataLen &&
+                  rel->rd_rel->reltoastrelid != InvalidOid)
+       {
+               int                     biggest_attno = -1;
+               int32           biggest_size = MAXALIGN(TOAST_POINTER_SIZE);
+               Datum           old_value;
+
+               /*--------
+                * Search for the biggest yet inlined attribute with
+                * attstorage = 'm'
+                *--------
+                */
+               for (i = 0; i < numAttrs; i++)
+               {
+                       if (toast_action[i] == 'p')
+                               continue;
+                       if (VARATT_IS_EXTERNAL(DatumGetPointer(toast_values[i])))
+                               continue;               /* can't happen, toast_action would be 'p' */
+                       if (TupleDescAttr(tupleDesc, i)->attstorage != 'm')
+                               continue;
+                       if (toast_sizes[i] > biggest_size)
+                       {
+                               biggest_attno = i;
+                               biggest_size = toast_sizes[i];
+                       }
+               }
+
+               if (biggest_attno < 0)
+                       break;
+
+               /*
+                * Store this external
+                */
+               i = biggest_attno;
+               old_value = toast_values[i];
+               toast_action[i] = 'p';
+               toast_values[i] = toast_save_datum(rel, toast_values[i],
+                                                                                  toast_oldexternal[i], options);
+               if (toast_free[i])
+                       pfree(DatumGetPointer(old_value));
+               toast_free[i] = true;
+
+               need_change = true;
+               need_free = true;
+       }
+
+       /*
+        * In the case we toasted any values, we need to build a new heap tuple
+        * with the changed values.
+        */
+       if (need_change)
+       {
+               HeapTupleHeader olddata = newtup->t_data;
+               HeapTupleHeader new_data;
+               int32           new_header_len;
+               int32           new_data_len;
+               int32           new_tuple_len;
+
+               /*
+                * Calculate the new size of the tuple.
+                *
+                * Note: we used to assume here that the old tuple's t_hoff must equal
+                * the new_header_len value, but that was incorrect.  The old tuple
+                * might have a smaller-than-current natts, if there's been an ALTER
+                * TABLE ADD COLUMN since it was stored; and that would lead to a
+                * different conclusion about the size of the null bitmap, or even
+                * whether there needs to be one at all.
+                */
+               new_header_len = SizeofHeapTupleHeader;
+               if (has_nulls)
+                       new_header_len += BITMAPLEN(numAttrs);
+               new_header_len = MAXALIGN(new_header_len);
+               new_data_len = heap_compute_data_size(tupleDesc,
+                                                                                         toast_values, toast_isnull);
+               new_tuple_len = new_header_len + new_data_len;
+
+               /*
+                * Allocate and zero the space needed, and fill HeapTupleData fields.
+                */
+               result_tuple = (HeapTuple) palloc0(HEAPTUPLESIZE + new_tuple_len);
+               result_tuple->t_len = new_tuple_len;
+               result_tuple->t_self = newtup->t_self;
+               result_tuple->t_tableOid = newtup->t_tableOid;
+               new_data = (HeapTupleHeader) ((char *) result_tuple + HEAPTUPLESIZE);
+               result_tuple->t_data = new_data;
+
+               /*
+                * Copy the existing tuple header, but adjust natts and t_hoff.
+                */
+               memcpy(new_data, olddata, SizeofHeapTupleHeader);
+               HeapTupleHeaderSetNatts(new_data, numAttrs);
+               new_data->t_hoff = new_header_len;
+
+               /* Copy over the data, and fill the null bitmap if needed */
+               heap_fill_tuple(tupleDesc,
+                                               toast_values,
+                                               toast_isnull,
+                                               (char *) new_data + new_header_len,
+                                               new_data_len,
+                                               &(new_data->t_infomask),
+                                               has_nulls ? new_data->t_bits : NULL);
+       }
+       else
+               result_tuple = newtup;
+
+       /*
+        * Free allocated temp values
+        */
+       if (need_free)
+               for (i = 0; i < numAttrs; i++)
+                       if (toast_free[i])
+                               pfree(DatumGetPointer(toast_values[i]));
+
+       /*
+        * Delete external values from the old tuple
+        */
+       if (need_delold)
+               for (i = 0; i < numAttrs; i++)
+                       if (toast_delold[i])
+                               toast_delete_datum(rel, toast_oldvalues[i], false);
+
+       return result_tuple;
+}
+
+
+/* ----------
+ * toast_flatten_tuple -
+ *
+ *     "Flatten" a tuple to contain no out-of-line toasted fields.
+ *     (This does not eliminate compressed or short-header datums.)
+ *
+ *     Note: we expect the caller already checked HeapTupleHasExternal(tup),
+ *     so there is no need for a short-circuit path.
+ * ----------
+ */
+HeapTuple
+toast_flatten_tuple(HeapTuple tup, TupleDesc tupleDesc)
+{
+       HeapTuple       new_tuple;
+       int                     numAttrs = tupleDesc->natts;
+       int                     i;
+       Datum           toast_values[MaxTupleAttributeNumber];
+       bool            toast_isnull[MaxTupleAttributeNumber];
+       bool            toast_free[MaxTupleAttributeNumber];
+
+       /*
+        * Break down the tuple into fields.
+        */
+       Assert(numAttrs <= MaxTupleAttributeNumber);
+       heap_deform_tuple(tup, tupleDesc, toast_values, toast_isnull);
+
+       memset(toast_free, 0, numAttrs * sizeof(bool));
+
+       for (i = 0; i < numAttrs; i++)
+       {
+               /*
+                * Look at non-null varlena attributes
+                */
+               if (!toast_isnull[i] && TupleDescAttr(tupleDesc, i)->attlen == -1)
+               {
+                       struct varlena *new_value;
+
+                       new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
+                       if (VARATT_IS_EXTERNAL(new_value))
+                       {
+                               new_value = heap_tuple_fetch_attr(new_value);
+                               toast_values[i] = PointerGetDatum(new_value);
+                               toast_free[i] = true;
+                       }
+               }
+       }
+
+       /*
+        * Form the reconfigured tuple.
+        */
+       new_tuple = heap_form_tuple(tupleDesc, toast_values, toast_isnull);
+
+       /*
+        * Be sure to copy the tuple's identity fields.  We also make a point of
+        * copying visibility info, just in case anybody looks at those fields in
+        * a syscache entry.
+        */
+       new_tuple->t_self = tup->t_self;
+       new_tuple->t_tableOid = tup->t_tableOid;
+
+       new_tuple->t_data->t_choice = tup->t_data->t_choice;
+       new_tuple->t_data->t_ctid = tup->t_data->t_ctid;
+       new_tuple->t_data->t_infomask &= ~HEAP_XACT_MASK;
+       new_tuple->t_data->t_infomask |=
+               tup->t_data->t_infomask & HEAP_XACT_MASK;
+       new_tuple->t_data->t_infomask2 &= ~HEAP2_XACT_MASK;
+       new_tuple->t_data->t_infomask2 |=
+               tup->t_data->t_infomask2 & HEAP2_XACT_MASK;
+
+       /*
+        * Free allocated temp values
+        */
+       for (i = 0; i < numAttrs; i++)
+               if (toast_free[i])
+                       pfree(DatumGetPointer(toast_values[i]));
+
+       return new_tuple;
+}
+
+
+/* ----------
+ * toast_flatten_tuple_to_datum -
+ *
+ *     "Flatten" a tuple containing out-of-line toasted fields into a Datum.
+ *     The result is always palloc'd in the current memory context.
+ *
+ *     We have a general rule that Datums of container types (rows, arrays,
+ *     ranges, etc) must not contain any external TOAST pointers.  Without
+ *     this rule, we'd have to look inside each Datum when preparing a tuple
+ *     for storage, which would be expensive and would fail to extend cleanly
+ *     to new sorts of container types.
+ *
+ *     However, we don't want to say that tuples represented as HeapTuples
+ *     can't contain toasted fields, so instead this routine should be called
+ *     when such a HeapTuple is being converted into a Datum.
+ *
+ *     While we're at it, we decompress any compressed fields too.  This is not
+ *     necessary for correctness, but reflects an expectation that compression
+ *     will be more effective if applied to the whole tuple not individual
+ *     fields.  We are not so concerned about that that we want to deconstruct
+ *     and reconstruct tuples just to get rid of compressed fields, however.
+ *     So callers typically won't call this unless they see that the tuple has
+ *     at least one external field.
+ *
+ *     On the other hand, in-line short-header varlena fields are left alone.
+ *     If we "untoasted" them here, they'd just get changed back to short-header
+ *     format anyway within heap_fill_tuple.
+ * ----------
+ */
+Datum
+toast_flatten_tuple_to_datum(HeapTupleHeader tup,
+                                                        uint32 tup_len,
+                                                        TupleDesc tupleDesc)
+{
+       HeapTupleHeader new_data;
+       int32           new_header_len;
+       int32           new_data_len;
+       int32           new_tuple_len;
+       HeapTupleData tmptup;
+       int                     numAttrs = tupleDesc->natts;
+       int                     i;
+       bool            has_nulls = false;
+       Datum           toast_values[MaxTupleAttributeNumber];
+       bool            toast_isnull[MaxTupleAttributeNumber];
+       bool            toast_free[MaxTupleAttributeNumber];
+
+       /* Build a temporary HeapTuple control structure */
+       tmptup.t_len = tup_len;
+       ItemPointerSetInvalid(&(tmptup.t_self));
+       tmptup.t_tableOid = InvalidOid;
+       tmptup.t_data = tup;
+
+       /*
+        * Break down the tuple into fields.
+        */
+       Assert(numAttrs <= MaxTupleAttributeNumber);
+       heap_deform_tuple(&tmptup, tupleDesc, toast_values, toast_isnull);
+
+       memset(toast_free, 0, numAttrs * sizeof(bool));
+
+       for (i = 0; i < numAttrs; i++)
+       {
+               /*
+                * Look at non-null varlena attributes
+                */
+               if (toast_isnull[i])
+                       has_nulls = true;
+               else if (TupleDescAttr(tupleDesc, i)->attlen == -1)
+               {
+                       struct varlena *new_value;
+
+                       new_value = (struct varlena *) DatumGetPointer(toast_values[i]);
+                       if (VARATT_IS_EXTERNAL(new_value) ||
+                               VARATT_IS_COMPRESSED(new_value))
+                       {
+                               new_value = heap_tuple_untoast_attr(new_value);
+                               toast_values[i] = PointerGetDatum(new_value);
+                               toast_free[i] = true;
+                       }
+               }
+       }
+
+       /*
+        * Calculate the new size of the tuple.
+        *
+        * This should match the reconstruction code in toast_insert_or_update.
+        */
+       new_header_len = SizeofHeapTupleHeader;
+       if (has_nulls)
+               new_header_len += BITMAPLEN(numAttrs);
+       new_header_len = MAXALIGN(new_header_len);
+       new_data_len = heap_compute_data_size(tupleDesc,
+                                                                                 toast_values, toast_isnull);
+       new_tuple_len = new_header_len + new_data_len;
+
+       new_data = (HeapTupleHeader) palloc0(new_tuple_len);
+
+       /*
+        * Copy the existing tuple header, but adjust natts and t_hoff.
+        */
+       memcpy(new_data, tup, SizeofHeapTupleHeader);
+       HeapTupleHeaderSetNatts(new_data, numAttrs);
+       new_data->t_hoff = new_header_len;
+
+       /* Set the composite-Datum header fields correctly */
+       HeapTupleHeaderSetDatumLength(new_data, new_tuple_len);
+       HeapTupleHeaderSetTypeId(new_data, tupleDesc->tdtypeid);
+       HeapTupleHeaderSetTypMod(new_data, tupleDesc->tdtypmod);
+
+       /* Copy over the data, and fill the null bitmap if needed */
+       heap_fill_tuple(tupleDesc,
+                                       toast_values,
+                                       toast_isnull,
+                                       (char *) new_data + new_header_len,
+                                       new_data_len,
+                                       &(new_data->t_infomask),
+                                       has_nulls ? new_data->t_bits : NULL);
+
+       /*
+        * Free allocated temp values
+        */
+       for (i = 0; i < numAttrs; i++)
+               if (toast_free[i])
+                       pfree(DatumGetPointer(toast_values[i]));
+
+       return PointerGetDatum(new_data);
+}
+
+
+/* ----------
+ * toast_build_flattened_tuple -
+ *
+ *     Build a tuple containing no out-of-line toasted fields.
+ *     (This does not eliminate compressed or short-header datums.)
+ *
+ *     This is essentially just like heap_form_tuple, except that it will
+ *     expand any external-data pointers beforehand.
+ *
+ *     It's not very clear whether it would be preferable to decompress
+ *     in-line compressed datums while at it.  For now, we don't.
+ * ----------
+ */
+HeapTuple
+toast_build_flattened_tuple(TupleDesc tupleDesc,
+                                                       Datum *values,
+                                                       bool *isnull)
+{
+       HeapTuple       new_tuple;
+       int                     numAttrs = tupleDesc->natts;
+       int                     num_to_free;
+       int                     i;
+       Datum           new_values[MaxTupleAttributeNumber];
+       Pointer         freeable_values[MaxTupleAttributeNumber];
+
+       /*
+        * We can pass the caller's isnull array directly to heap_form_tuple, but
+        * we potentially need to modify the values array.
+        */
+       Assert(numAttrs <= MaxTupleAttributeNumber);
+       memcpy(new_values, values, numAttrs * sizeof(Datum));
+
+       num_to_free = 0;
+       for (i = 0; i < numAttrs; i++)
+       {
+               /*
+                * Look at non-null varlena attributes
+                */
+               if (!isnull[i] && TupleDescAttr(tupleDesc, i)->attlen == -1)
+               {
+                       struct varlena *new_value;
+
+                       new_value = (struct varlena *) DatumGetPointer(new_values[i]);
+                       if (VARATT_IS_EXTERNAL(new_value))
+                       {
+                               new_value = heap_tuple_fetch_attr(new_value);
+                               new_values[i] = PointerGetDatum(new_value);
+                               freeable_values[num_to_free++] = (Pointer) new_value;
+                       }
+               }
+       }
+
+       /*
+        * Form the reconfigured tuple.
+        */
+       new_tuple = heap_form_tuple(tupleDesc, new_values, isnull);
+
+       /*
+        * Free allocated temp values
+        */
+       for (i = 0; i < num_to_free; i++)
+               pfree(freeable_values[i]);
+
+       return new_tuple;
+}
index 72a448ad31677d01f52aee2b032003f28abd15bd..9f4f60a7c3545e5d765b396c47fe08d165a43c10 100644 (file)
 
 #include "access/heapam.h"
 #include "access/heapam_xlog.h"
+#include "access/heaptoast.h"
 #include "access/rewriteheap.h"
 #include "access/transam.h"
-#include "access/tuptoaster.h"
 #include "access/xact.h"
 #include "access/xloginsert.h"
 
index 99e4322e9b8b5c318b9d2fd680cb2a9dc679282c..dcc0c0f02dee32837d231bc10dca599e68b09c03 100644 (file)
 
 #include "access/clog.h"
 #include "access/commit_ts.h"
+#include "access/heaptoast.h"
 #include "access/multixact.h"
 #include "access/rewriteheap.h"
 #include "access/subtrans.h"
 #include "access/timeline.h"
 #include "access/transam.h"
-#include "access/tuptoaster.h"
 #include "access/twophase.h"
 #include "access/undolog.h"
 #include "access/xact.h"
index 8d633f2585160e58f599adfec9d980eb9d52dde1..16acc2dca288067171292fe60d8e94ff70f2da92 100644 (file)
@@ -16,6 +16,7 @@
 
 #include <math.h>
 
+#include "access/detoast.h"
 #include "access/genam.h"
 #include "access/multixact.h"
 #include "access/relation.h"
@@ -24,7 +25,6 @@
 #include "access/tableam.h"
 #include "access/transam.h"
 #include "access/tupconvert.h"
-#include "access/tuptoaster.h"
 #include "access/visibilitymap.h"
 #include "access/xact.h"
 #include "catalog/catalog.h"
index ebaec4f8dd9e9b3935d0134ec3547e390e26b620..7b383499e9f5432a6278845c7cb0274afdaf861e 100644 (file)
@@ -23,7 +23,7 @@
 #include "access/relscan.h"
 #include "access/tableam.h"
 #include "access/transam.h"
-#include "access/tuptoaster.h"
+#include "access/toast_internals.h"
 #include "access/xact.h"
 #include "access/xlog.h"
 #include "catalog/pg_am.h"
index 66a67c72b29a4287641f6b322c762b353c08b5be..cfd3aa1fb86aebdbabc5ccad184353c65d380fb3 100644 (file)
@@ -56,7 +56,7 @@
  */
 #include "postgres.h"
 
-#include "access/tuptoaster.h"
+#include "access/heaptoast.h"
 #include "catalog/pg_type.h"
 #include "commands/sequence.h"
 #include "executor/execExpr.h"
index 5ee2a464bb448c213e40b2c66acd9067cde69152..82b69456ad441f5d1514a8cda6432bf2d122280c 100644 (file)
@@ -57,9 +57,9 @@
  */
 #include "postgres.h"
 
+#include "access/heaptoast.h"
 #include "access/htup_details.h"
 #include "access/tupdesc_details.h"
-#include "access/tuptoaster.h"
 #include "funcapi.h"
 #include "catalog/pg_type.h"
 #include "nodes/nodeFuncs.h"
index cf79feb6bdfa3c38b3f2d65ec9dfa50851916244..c0c81c82da0529c925362e95ead53ffab703fbc5 100644 (file)
@@ -20,7 +20,7 @@
 
 #include "postgres.h"
 
-#include "access/tuptoaster.h"
+#include "access/detoast.h"
 #include "executor/tstoreReceiver.h"
 
 
index e8ffa0492f1dc8d8d4dcf57600813d3ec308d2c7..0bb008414f683a83c67589d9665a70d1cfe702a3 100644 (file)
 #include <unistd.h>
 #include <sys/stat.h>
 
+#include "access/detoast.h"
 #include "access/heapam.h"
 #include "access/rewriteheap.h"
 #include "access/transam.h"
-#include "access/tuptoaster.h"
 #include "access/xact.h"
 #include "access/xlog_internal.h"
 #include "catalog/catalog.h"
index c56ed48270662b22659a97ee7384162b253f5f44..6167f7956857249106c9bde15e0b69352386b6ae 100644 (file)
  */
 #include "postgres.h"
 
+#include "access/detoast.h"
 #include "access/genam.h"
 #include "access/htup_details.h"
 #include "access/table.h"
-#include "access/tuptoaster.h"
 #include "catalog/indexing.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_statistic_ext.h"
index a477cb920011f599aac092292d055959bedb61d6..e5912363433ec3319ba08b0e7fecdf84c8524e1d 100644 (file)
 
 #include <limits.h>
 
+#include "access/detoast.h"
 #include "access/genam.h"
+#include "access/htup_details.h"
 #include "access/sysattr.h"
 #include "access/table.h"
-#include "access/tuptoaster.h"
 #include "access/xact.h"
 #include "catalog/dependency.h"
 #include "catalog/indexing.h"
index eafb94b697e3985f270e1705ad7e36fbeb68b908..54f584962909aa14fc67772e4d454706b5991569 100644 (file)
@@ -14,7 +14,7 @@
  */
 #include "postgres.h"
 
-#include "access/tuptoaster.h"
+#include "access/detoast.h"
 #include "commands/vacuum.h"
 #include "utils/array.h"
 #include "utils/builtins.h"
index 81ea5a48e597bc64520488c5054b956585681fb1..1568658bc9cfc4f936dd03d7c9f57558bfe8fb8f 100644 (file)
@@ -42,7 +42,7 @@
 
 #include "postgres.h"
 
-#include "access/tuptoaster.h"
+#include "access/detoast.h"
 #include "fmgr.h"
 #include "utils/datum.h"
 #include "utils/expandeddatum.h"
index 166c8630267bc5a4298e1250de8f5a6b8dcdb365..369432d53cb6f6aae7f8bf661f6eb12538448ce6 100644 (file)
@@ -18,8 +18,9 @@
  */
 #include "postgres.h"
 
+#include "access/detoast.h"
+#include "access/heaptoast.h"
 #include "access/htup_details.h"
-#include "access/tuptoaster.h"
 #include "catalog/heap.h"
 #include "catalog/pg_type.h"
 #include "utils/builtins.h"
index aa7ec8735c4a104249f659b5b66b5521a9c5b4b0..ea3e40a369429d7b0f2f04fb0a5c062898b2bd65 100644 (file)
@@ -16,8 +16,8 @@
 
 #include <ctype.h>
 
+#include "access/detoast.h"
 #include "access/htup_details.h"
-#include "access/tuptoaster.h"
 #include "catalog/pg_type.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
index 4f256260fd11387f96bfcd02e6410a8eb27ffc51..6ff71a49b8fa35d6da194fa4a364ae03edbc8ed1 100644 (file)
@@ -15,7 +15,7 @@
 #include "postgres.h"
 
 #include "access/gist.h"
-#include "access/tuptoaster.h"
+#include "access/heaptoast.h"
 #include "port/pg_bitutils.h"
 #include "tsearch/ts_utils.h"
 #include "utils/builtins.h"
index 332dc860c4f85284edbd3d71fc8c8190a658965a..9d9439932308b179894b5bc3ebd2f4e10f5c236e 100644 (file)
@@ -14,7 +14,7 @@
  */
 #include "postgres.h"
 
-#include "access/tuptoaster.h"
+#include "access/detoast.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_type.h"
 #include "libpq/pqformat.h"
index 0864838867f6d3a7ff9d4db4b8c55c32ec675d0a..36852239228d2e7acc715ab8325c2ca1c024f973 100644 (file)
@@ -17,7 +17,7 @@
 #include <ctype.h>
 #include <limits.h>
 
-#include "access/tuptoaster.h"
+#include "access/detoast.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_type.h"
 #include "common/int.h"
index 00def27881d4361f933ee96732074f1b0a084502..c3e7d94aa5b325046b8c014b1093abe54d7ff881 100644 (file)
 #include "postgres.h"
 
 #include "access/genam.h"
+#include "access/heaptoast.h"
 #include "access/relscan.h"
 #include "access/sysattr.h"
 #include "access/table.h"
-#include "access/tuptoaster.h"
 #include "access/valid.h"
 #include "access/xact.h"
 #include "catalog/pg_collation.h"
index 9b640ccd406d2fcbfb7c331169b6ced7919852c8..74e36e62d32e89cb148af3f23bfebba45f2308a5 100644 (file)
@@ -15,7 +15,7 @@
 
 #include "postgres.h"
 
-#include "access/tuptoaster.h"
+#include "access/detoast.h"
 #include "catalog/pg_language.h"
 #include "catalog/pg_proc.h"
 #include "executor/functions.h"
index ad96fe75af543981e47acff3fecce9cfbb48f90a..0c213497161927e37b296d54b16976ed7d0b0d10 100644 (file)
@@ -45,7 +45,7 @@
 #include <unistd.h>
 
 #include "access/transam.h"
-#include "access/tuptoaster.h"
+#include "access/heaptoast.h"
 #include "access/multixact.h"
 #include "access/xlog.h"
 #include "access/xlog_internal.h"
diff --git a/src/include/access/detoast.h b/src/include/access/detoast.h
new file mode 100644 (file)
index 0000000..2a2d1cc
--- /dev/null
@@ -0,0 +1,92 @@
+/*-------------------------------------------------------------------------
+ *
+ * detoast.h
+ *       Access to compressed and external varlena values.
+ *
+ * Copyright (c) 2000-2019, PostgreSQL Global Development Group
+ *
+ * src/include/access/detoast.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef DETOAST_H
+#define DETOAST_H
+
+/*
+ * Testing whether an externally-stored value is compressed now requires
+ * comparing extsize (the actual length of the external data) to rawsize
+ * (the original uncompressed datum's size).  The latter includes VARHDRSZ
+ * overhead, the former doesn't.  We never use compression unless it actually
+ * saves space, so we expect either equality or less-than.
+ */
+#define VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer) \
+       ((toast_pointer).va_extsize < (toast_pointer).va_rawsize - VARHDRSZ)
+
+/*
+ * Macro to fetch the possibly-unaligned contents of an EXTERNAL datum
+ * into a local "struct varatt_external" toast pointer.  This should be
+ * just a memcpy, but some versions of gcc seem to produce broken code
+ * that assumes the datum contents are aligned.  Introducing an explicit
+ * intermediate "varattrib_1b_e *" variable seems to fix it.
+ */
+#define VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr) \
+do { \
+       varattrib_1b_e *attre = (varattrib_1b_e *) (attr); \
+       Assert(VARATT_IS_EXTERNAL(attre)); \
+       Assert(VARSIZE_EXTERNAL(attre) == sizeof(toast_pointer) + VARHDRSZ_EXTERNAL); \
+       memcpy(&(toast_pointer), VARDATA_EXTERNAL(attre), sizeof(toast_pointer)); \
+} while (0)
+
+/* Size of an EXTERNAL datum that contains a standard TOAST pointer */
+#define TOAST_POINTER_SIZE (VARHDRSZ_EXTERNAL + sizeof(varatt_external))
+
+/* Size of an EXTERNAL datum that contains an indirection pointer */
+#define INDIRECT_POINTER_SIZE (VARHDRSZ_EXTERNAL + sizeof(varatt_indirect))
+
+/* ----------
+ * heap_tuple_fetch_attr() -
+ *
+ *             Fetches an external stored attribute from the toast
+ *             relation. Does NOT decompress it, if stored external
+ *             in compressed format.
+ * ----------
+ */
+extern struct varlena *heap_tuple_fetch_attr(struct varlena *attr);
+
+/* ----------
+ * heap_tuple_untoast_attr() -
+ *
+ *             Fully detoasts one attribute, fetching and/or decompressing
+ *             it as needed.
+ * ----------
+ */
+extern struct varlena *heap_tuple_untoast_attr(struct varlena *attr);
+
+/* ----------
+ * heap_tuple_untoast_attr_slice() -
+ *
+ *             Fetches only the specified portion of an attribute.
+ *             (Handles all cases for attribute storage)
+ * ----------
+ */
+extern struct varlena *heap_tuple_untoast_attr_slice(struct varlena *attr,
+                                                                                                        int32 sliceoffset,
+                                                                                                        int32 slicelength);
+
+/* ----------
+ * toast_raw_datum_size -
+ *
+ *     Return the raw (detoasted) size of a varlena datum
+ * ----------
+ */
+extern Size toast_raw_datum_size(Datum value);
+
+/* ----------
+ * toast_datum_size -
+ *
+ *     Return the storage size of a varlena datum
+ * ----------
+ */
+extern Size toast_datum_size(Datum value);
+
+#endif                                                 /* DETOAST_H */
similarity index 57%
rename from src/include/access/tuptoaster.h
rename to src/include/access/heaptoast.h
index f0aea2496bf733c9411260d5592640d3aac0d9ea..bf02d2c6001fe9949d0002df2e4b38dec17433b0 100644 (file)
@@ -1,29 +1,22 @@
 /*-------------------------------------------------------------------------
  *
- * tuptoaster.h
- *       POSTGRES definitions for external and compressed storage
+ * heaptoast.h
+ *       Heap-specific definitions for external and compressed storage
  *       of variable size attributes.
  *
  * Copyright (c) 2000-2019, PostgreSQL Global Development Group
  *
- * src/include/access/tuptoaster.h
+ * src/include/access/heaptoast.h
  *
  *-------------------------------------------------------------------------
  */
-#ifndef TUPTOASTER_H
-#define TUPTOASTER_H
+#ifndef HEAPTOAST_H
+#define HEAPTOAST_H
 
 #include "access/htup_details.h"
 #include "storage/lockdefs.h"
 #include "utils/relcache.h"
 
-/*
- * This enables de-toasting of index entries.  Needed until VACUUM is
- * smart enough to rebuild indexes from scratch.
- */
-#define TOAST_INDEX_HACK
-
-
 /*
  * Find the maximum size of a tuple if there are to be N tuples per page.
  */
         sizeof(int32) -                                                                        \
         VARHDRSZ)
 
-/* Size of an EXTERNAL datum that contains a standard TOAST pointer */
-#define TOAST_POINTER_SIZE (VARHDRSZ_EXTERNAL + sizeof(varatt_external))
-
-/* Size of an EXTERNAL datum that contains an indirection pointer */
-#define INDIRECT_POINTER_SIZE (VARHDRSZ_EXTERNAL + sizeof(varatt_indirect))
-
-/*
- * Testing whether an externally-stored value is compressed now requires
- * comparing extsize (the actual length of the external data) to rawsize
- * (the original uncompressed datum's size).  The latter includes VARHDRSZ
- * overhead, the former doesn't.  We never use compression unless it actually
- * saves space, so we expect either equality or less-than.
- */
-#define VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer) \
-       ((toast_pointer).va_extsize < (toast_pointer).va_rawsize - VARHDRSZ)
-
-/*
- * Macro to fetch the possibly-unaligned contents of an EXTERNAL datum
- * into a local "struct varatt_external" toast pointer.  This should be
- * just a memcpy, but some versions of gcc seem to produce broken code
- * that assumes the datum contents are aligned.  Introducing an explicit
- * intermediate "varattrib_1b_e *" variable seems to fix it.
- */
-#define VARATT_EXTERNAL_GET_POINTER(toast_pointer, attr) \
-do { \
-       varattrib_1b_e *attre = (varattrib_1b_e *) (attr); \
-       Assert(VARATT_IS_EXTERNAL(attre)); \
-       Assert(VARSIZE_EXTERNAL(attre) == sizeof(toast_pointer) + VARHDRSZ_EXTERNAL); \
-       memcpy(&(toast_pointer), VARDATA_EXTERNAL(attre), sizeof(toast_pointer)); \
-} while (0)
-
 /* ----------
  * toast_insert_or_update -
  *
@@ -144,36 +106,6 @@ extern HeapTuple toast_insert_or_update(Relation rel,
  */
 extern void toast_delete(Relation rel, HeapTuple oldtup, bool is_speculative);
 
-/* ----------
- * heap_tuple_fetch_attr() -
- *
- *             Fetches an external stored attribute from the toast
- *             relation. Does NOT decompress it, if stored external
- *             in compressed format.
- * ----------
- */
-extern struct varlena *heap_tuple_fetch_attr(struct varlena *attr);
-
-/* ----------
- * heap_tuple_untoast_attr() -
- *
- *             Fully detoasts one attribute, fetching and/or decompressing
- *             it as needed.
- * ----------
- */
-extern struct varlena *heap_tuple_untoast_attr(struct varlena *attr);
-
-/* ----------
- * heap_tuple_untoast_attr_slice() -
- *
- *             Fetches only the specified portion of an attribute.
- *             (Handles all cases for attribute storage)
- * ----------
- */
-extern struct varlena *heap_tuple_untoast_attr_slice(struct varlena *attr,
-                                                                                                        int32 sliceoffset,
-                                                                                                        int32 slicelength);
-
 /* ----------
  * toast_flatten_tuple -
  *
@@ -204,36 +136,4 @@ extern HeapTuple toast_build_flattened_tuple(TupleDesc tupleDesc,
                                                                                         Datum *values,
                                                                                         bool *isnull);
 
-/* ----------
- * toast_compress_datum -
- *
- *     Create a compressed version of a varlena datum, if possible
- * ----------
- */
-extern Datum toast_compress_datum(Datum value);
-
-/* ----------
- * toast_raw_datum_size -
- *
- *     Return the raw (detoasted) size of a varlena datum
- * ----------
- */
-extern Size toast_raw_datum_size(Datum value);
-
-/* ----------
- * toast_datum_size -
- *
- *     Return the storage size of a varlena datum
- * ----------
- */
-extern Size toast_datum_size(Datum value);
-
-/* ----------
- * toast_get_valid_index -
- *
- *     Return OID of valid index associated to a toast relation
- * ----------
- */
-extern Oid     toast_get_valid_index(Oid toastoid, LOCKMODE lock);
-
-#endif                                                 /* TUPTOASTER_H */
+#endif                                                 /* HEAPTOAST_H */
diff --git a/src/include/access/toast_internals.h b/src/include/access/toast_internals.h
new file mode 100644 (file)
index 0000000..8ac367f
--- /dev/null
@@ -0,0 +1,54 @@
+/*-------------------------------------------------------------------------
+ *
+ * toast_internals.h
+ *       Internal definitions for the TOAST system.
+ *
+ * Copyright (c) 2000-2019, PostgreSQL Global Development Group
+ *
+ * src/include/access/toast_internals.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef TOAST_INTERNALS_H
+#define TOAST_INTERNALS_H
+
+#include "storage/lockdefs.h"
+#include "utils/relcache.h"
+#include "utils/snapshot.h"
+
+/*
+ *     The information at the start of the compressed toast data.
+ */
+typedef struct toast_compress_header
+{
+       int32           vl_len_;                /* varlena header (do not touch directly!) */
+       int32           rawsize;
+} toast_compress_header;
+
+/*
+ * Utilities for manipulation of header information for compressed
+ * toast entries.
+ */
+#define TOAST_COMPRESS_HDRSZ           ((int32) sizeof(toast_compress_header))
+#define TOAST_COMPRESS_RAWSIZE(ptr) (((toast_compress_header *) (ptr))->rawsize)
+#define TOAST_COMPRESS_RAWDATA(ptr) \
+       (((char *) (ptr)) + TOAST_COMPRESS_HDRSZ)
+#define TOAST_COMPRESS_SET_RAWSIZE(ptr, len) \
+       (((toast_compress_header *) (ptr))->rawsize = (len))
+
+extern Datum toast_compress_datum(Datum value);
+extern Oid     toast_get_valid_index(Oid toastoid, LOCKMODE lock);
+
+extern void toast_delete_datum(Relation rel, Datum value, bool is_speculative);
+extern Datum toast_save_datum(Relation rel, Datum value,
+                                struct varlena *oldexternal, int options);
+
+extern int toast_open_indexes(Relation toastrel,
+                                  LOCKMODE lock,
+                                  Relation **toastidxs,
+                                  int *num_indexes);
+extern void toast_close_indexes(Relation *toastidxs, int num_indexes,
+                                       LOCKMODE lock);
+extern void init_toast_snapshot(Snapshot toast_snapshot);
+
+#endif                                                 /* TOAST_INTERNALS_H */
index f5fdf93d0a4abb9b1e1dce371581868a02692568..db2eff1bbbc162030e5bfa2ae069706b1242151d 100644 (file)
 
 #include <ctype.h>
 
+#include "access/detoast.h"
 #include "access/htup_details.h"
 #include "access/transam.h"
 #include "access/tupconvert.h"
-#include "access/tuptoaster.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
 #include "commands/defrem.h"
index 7f03b7e857bfbbf852bf57761b430c135bcabb0b..826556eb2942cb72580ee32daaad3a51d085bbc1 100644 (file)
@@ -19,9 +19,9 @@
 #include <math.h>
 #include <signal.h>
 
+#include "access/detoast.h"
 #include "access/htup_details.h"
 #include "access/transam.h"
-#include "access/tuptoaster.h"
 #include "access/xact.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_type.h"