Simplify SortTocFromFile() by removing fixed buffer-size limit.

pg_restore previously coped with overlength TOC-file lines using some
complicated logic to ignore additional bufferloads.  While this isn't
wrong, since we don't expect that the interesting part of a line would
run to more than a dozen or so bytes, it's more complex than it needs
to be.  Use a StringInfo instead of a fixed-size buffer so that we can
process long lines as single entities and thus not need the extra
logic.

Daniel Gustafsson

Discussion: https://postgr.es/m/48A4FA71-524E-41B9-953A-FD04EF36E2E7@yesql.se

diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c
index bc4757829430da59b9fdb209003293019aea0282..3567e9f365f53bdec991279cc2fcfc918874f135 100644 (file)
--- a/src/bin/pg_dump/pg_backup_archiver.c
+++ b/src/bin/pg_dump/pg_backup_archiver.c
@@ -30,8 +30,10 @@
 #include <io.h>
 #endif
 
+#include "common/string.h"
 #include "dumputils.h"
 #include "fe_utils/string_utils.h"
+#include "lib/stringinfo.h"
 #include "libpq/libpq-fs.h"
 #include "parallel.h"
 #include "pg_backup_archiver.h"
@@ -1367,8 +1369,7 @@ SortTocFromFile(Archive *AHX)
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
    RestoreOptions *ropt = AH->public.ropt;
    FILE       *fh;
-   char        buf[100];
-   bool        incomplete_line;
+   StringInfoData linebuf;
 
    /* Allocate space for the 'wanted' array, and init it */
    ropt->idWanted = (bool *) pg_malloc0(sizeof(bool) * AH->maxDumpId);
@@ -1378,45 +1379,33 @@ SortTocFromFile(Archive *AHX)
    if (!fh)
        fatal("could not open TOC file \"%s\": %m", ropt->tocFile);
 
-   incomplete_line = false;
-   while (fgets(buf, sizeof(buf), fh) != NULL)
+   initStringInfo(&linebuf);
+
+   while (pg_get_line_buf(fh, &linebuf))
    {
-       bool        prev_incomplete_line = incomplete_line;
-       int         buflen;
        char       *cmnt;
        char       *endptr;
        DumpId      id;
        TocEntry   *te;
 
-       /*
-        * Some lines in the file might be longer than sizeof(buf).  This is
-        * no problem, since we only care about the leading numeric ID which
-        * can be at most a few characters; but we have to skip continuation
-        * bufferloads when processing a long line.
-        */
-       buflen = strlen(buf);
-       if (buflen > 0 && buf[buflen - 1] == '\n')
-           incomplete_line = false;
-       else
-           incomplete_line = true;
-       if (prev_incomplete_line)
-           continue;
-
        /* Truncate line at comment, if any */
-       cmnt = strchr(buf, ';');
+       cmnt = strchr(linebuf.data, ';');
        if (cmnt != NULL)
+       {
            cmnt[0] = '\0';
+           linebuf.len = cmnt - linebuf.data;
+       }
 
        /* Ignore if all blank */
-       if (strspn(buf, " \t\r\n") == strlen(buf))
+       if (strspn(linebuf.data, " \t\r\n") == linebuf.len)
            continue;
 
        /* Get an ID, check it's valid and not already seen */
-       id = strtol(buf, &endptr, 10);
-       if (endptr == buf || id <= 0 || id > AH->maxDumpId ||
+       id = strtol(linebuf.data, &endptr, 10);
+       if (endptr == linebuf.data || id <= 0 || id > AH->maxDumpId ||
            ropt->idWanted[id - 1])
        {
-           pg_log_warning("line ignored: %s", buf);
+           pg_log_warning("line ignored: %s", linebuf.data);
            continue;
        }
 
@@ -1443,6 +1432,8 @@ SortTocFromFile(Archive *AHX)
        _moveBefore(AH->toc, te);
    }
 
+   pg_free(linebuf.data);
+
    if (fclose(fh) != 0)
        fatal("could not close TOC file: %m");
 }