Changeset 42344 in webkit for trunk/JavaScriptCore/wtf/FastMalloc.cpp

Timestamp:

Apr 8, 2009, 6:14:07 PM (16 years ago)

Author:

[email protected]

Message:

2009-04-08 Paul Pedriana <​[email protected]>

Reviewed by Darin Adler.

​https://bugs.webkit.org/show_bug.cgi?id=20422
Allow custom memory allocation control.

• wtf/FastAllocBase.h: New added file. Implements allocation base class.
• wtf/TypeTraits.h: Augments existing type traits support as needed by FastAllocBase.
• wtf/FastMalloc.h: Changed to support FastMalloc match validation.
• wtf/FastMalloc.cpp: Changed to support FastMalloc match validation.
• wtf/Platform.h: Added ENABLE_FAST_MALLOC_MATCH_VALIDATION; defaults to 0.
• GNUmakefile.am: Updated to include added FastAllocBase.h.
• JavaScriptCore.xcodeproj/project.pbxproj: Updated to include added FastAllocBase.h.
• JavaScriptCore.vcproj/WTF/WTF.vcproj: Updated to include added FastAllocBase.h.

File:

• trunk/JavaScriptCore/wtf/FastMalloc.cpp (modified) (16 diffs)

trunk/JavaScriptCore/wtf/FastMalloc.cpp

@@ -79 +79 @@
 
 #include "Assertions.h"
+#include <limits>
 #if ENABLE(JSC_MULTIPLE_THREADS)
 #include <pthread.h>
@@ -151 +152 @@
 
 namespace WTF {
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+
+namespace Internal {
+
+void fastMallocMatchFailed(void*)
+{
+    CRASH();
+}
+
+} // namespace Internal
+
+#endif
 
 void* fastZeroedMalloc(size_t n) 
@@ -184 +198 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (std::numeric_limits<size_t>::max() - sizeof(AllocAlignmentInteger) <= n)  // If overflow would occur...
+        return 0;
+
+    void* result = malloc(n + sizeof(AllocAlignmentInteger));
+    if (!result)
+        return 0;
+
+    *static_cast<AllocAlignmentInteger*>(result) = Internal::AllocTypeMalloc;
+    result = static_cast<AllocAlignmentInteger*>(result) + 1;
+
+    return result;
+#else
     return malloc(n);
+#endif
 }
 
@@ -190 +219 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    void* result = tryFastMalloc(n);
+#else
     void* result = malloc(n);
+#endif
+
     if (!result)
         CRASH();
@@ -199 +234 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    size_t totalBytes = n_elements * element_size;
+    if (n_elements > 1 && element_size && (totalBytes / element_size) != n_elements || (std::numeric_limits<size_t>::max() - sizeof(AllocAlignmentInteger) <= totalBytes))
+        return 0;
+
+    totalBytes += sizeof(AllocAlignmentInteger);
+    void* result = malloc(totalBytes);
+    if (!result)
+        return 0;
+
+    memset(result, 0, totalBytes);
+    *static_cast<AllocAlignmentInteger*>(result) = Internal::AllocTypeMalloc;
+    result = static_cast<AllocAlignmentInteger*>(result) + 1;
+    return result;
+#else
     return calloc(n_elements, element_size);
+#endif
 }
 
@@ -205 +257 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    void* result = tryFastCalloc(n_elements, element_size);
+#else
     void* result = calloc(n_elements, element_size);
+#endif
+
     if (!result)
         CRASH();
@@ -214 +272 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (!p)
+        return;
+
+    AllocAlignmentInteger* header = Internal::fastMallocMatchValidationValue(p);
+    if (*header != Internal::AllocTypeMalloc)
+        Internal::fastMallocMatchFailed(p);
+    free(header);
+#else
     free(p);
+#endif
 }
 
@@ -220 +289 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (p) {
+        if (std::numeric_limits<size_t>::max() - sizeof(AllocAlignmentInteger) <= n)  // If overflow would occur...
+            return 0;
+        AllocAlignmentInteger* header = Internal::fastMallocMatchValidationValue(p);
+        if (*header != Internal::AllocTypeMalloc)
+            Internal::fastMallocMatchFailed(p);
+        void* result = realloc(header, n + sizeof(AllocAlignmentInteger));
+        if (!result)
+            return 0;
+
+        // This should not be needed because the value is already there:
+        // *static_cast<AllocAlignmentInteger*>(result) = Internal::AllocTypeMalloc;
+        result = static_cast<AllocAlignmentInteger*>(result) + 1;
+        return result;
+    } else {
+        return fastMalloc(n);
+    }
+#else
     return realloc(p, n);
+#endif
 }
 
@@ -226 +316 @@
 {
     ASSERT(!isForbidden());
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    void* result = tryFastRealloc(p, n);
+#else
     void* result = realloc(p, n);
+#endif
+
     if (!result)
         CRASH();
@@ -266 +362 @@
 #include <algorithm>
 #include <errno.h>
+#include <limits>
 #include <new>
 #include <pthread.h>
@@ -3295 +3392 @@
 #endif
 void* malloc(size_t size) {
-  void* result = do_malloc(size);
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (std::numeric_limits<size_t>::max() - sizeof(AllocAlignmentInteger) <= size)  // If overflow would occur...
+        return 0;
+    size += sizeof(AllocAlignmentInteger);
+    void* result = do_malloc(size);
+    if (!result)
+        return 0;
+
+    *static_cast<AllocAlignmentInteger*>(result) = Internal::AllocTypeMalloc;
+    result = static_cast<AllocAlignmentInteger*>(result) + 1;
+#else
+    void* result = do_malloc(size);
+#endif
+
 #ifndef WTF_CHANGES
   MallocHook::InvokeNewHook(result, size);
@@ -3309 +3419 @@
   MallocHook::InvokeDeleteHook(ptr);
 #endif
-  do_free(ptr);
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (!ptr)
+        return;
+
+    AllocAlignmentInteger* header = Internal::fastMallocMatchValidationValue(ptr);
+    if (*header != Internal::AllocTypeMalloc)
+        Internal::fastMallocMatchFailed(ptr);
+    do_free(header);
+#else
+    do_free(ptr);
+#endif
 }
 
@@ -3332 +3453 @@
 #endif
 void* calloc(size_t n, size_t elem_size) {
-  const size_t totalBytes = n * elem_size;
+  size_t totalBytes = n * elem_size;
     
   // Protect against overflow
   if (n > 1 && elem_size && (totalBytes / elem_size) != n)
     return 0;
-    
-  void* result = do_malloc(totalBytes);
-  if (result != NULL) {
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (std::numeric_limits<size_t>::max() - sizeof(AllocAlignmentInteger) <= totalBytes)  // If overflow would occur...
+        return 0;
+
+    totalBytes += sizeof(AllocAlignmentInteger);
+    void* result = do_malloc(totalBytes);
+    if (!result)
+        return 0;
+
     memset(result, 0, totalBytes);
-  }
+    *static_cast<AllocAlignmentInteger*>(result) = Internal::AllocTypeMalloc;
+    result = static_cast<AllocAlignmentInteger*>(result) + 1;
+#else
+    void* result = do_malloc(totalBytes);
+    if (result != NULL) {
+        memset(result, 0, totalBytes);
+    }
+#endif
+
 #ifndef WTF_CHANGES
   MallocHook::InvokeNewHook(result, totalBytes);
@@ -3382 +3518 @@
 void* realloc(void* old_ptr, size_t new_size) {
   if (old_ptr == NULL) {
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    void* result = malloc(new_size);
+#else
     void* result = do_malloc(new_size);
 #ifndef WTF_CHANGES
     MallocHook::InvokeNewHook(result, new_size);
 #endif
+#endif
     return result;
   }
@@ -3395 +3535 @@
     return NULL;
   }
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    if (std::numeric_limits<size_t>::max() - sizeof(AllocAlignmentInteger) <= new_size)  // If overflow would occur...
+        return 0;
+    new_size += sizeof(AllocAlignmentInteger);
+    AllocAlignmentInteger* header = Internal::fastMallocMatchValidationValue(old_ptr);
+    if (*header != Internal::AllocTypeMalloc)
+        Internal::fastMallocMatchFailed(old_ptr);
+    old_ptr = header;
+#endif
 
   // Get the size of the old entry
@@ -3432 +3582 @@
     // would be small, so don't bother.
     do_free(old_ptr);
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    new_ptr = static_cast<AllocAlignmentInteger*>(new_ptr) + 1;
+#endif
     return new_ptr;
   } else {
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+    old_ptr = pByte + sizeof(AllocAlignmentInteger);  // Set old_ptr back to the user pointer.
+#endif
     return old_ptr;
   }