begin cleanup of malloc porting layer

1. Merge some of the allocators into sk_malloc_flags by redefining a flag to mean zero-init
2. Add more private helpers to simplify our call-sites (and handle some overflow mul checks)
3. The 2-param helpers rely on the saturating SkSafeMath::Mul to pass max_size_t as the request,
which should always fail.

Bug:508641
Change-Id: I322f1e6ed91113467e0fdb12c91c3dad33d890c8
Reviewed-on: https://skia-review.googlesource.com/90940
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Reviewed-by: Stephan Altmueller <stephana@google.com>

1 files changed, 24 insertions, 7 deletions

diff --git a/src/core/SkMallocPixelRef.cpp b/src/core/SkMallocPixelRef.cpp
index 6e402c98f7..2933e48cc4 100644
--- a/src/core/SkMallocPixelRef.cpp
+++ b/src/core/SkMallocPixelRef.cpp
@@ -8,8 +8,27 @@
 #include "SkMallocPixelRef.h"
 #include "SkBitmap.h"
 #include "SkReadBuffer.h"
+#include "SkSafeMath.h"
 #include "SkWriteBuffer.h"
 
+void* sk_calloc_throw(size_t count, size_t elemSize) {
+    return sk_calloc_throw(SkSafeMath::Mul(count, elemSize));
+}
+
+void* sk_malloc_throw(size_t count, size_t elemSize) {
+    return sk_malloc_throw(SkSafeMath::Mul(count, elemSize));
+}
+
+void* sk_realloc_throw(void* buffer, size_t count, size_t elemSize) {
+    return sk_realloc_throw(buffer, SkSafeMath::Mul(count, elemSize));
+}
+
+void* sk_malloc_canfail(size_t count, size_t elemSize) {
+    return sk_malloc_canfail(SkSafeMath::Mul(count, elemSize));
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
 // assumes ptr was allocated via sk_malloc
 static void sk_free_releaseproc(void* ptr, void*) {
     sk_free(ptr);
@@ -63,15 +82,13 @@ sk_sp<SkPixelRef> SkMallocPixelRef::MakeUsing(void*(*allocProc)(size_t),
                                                   sk_free_releaseproc, nullptr));
 }
 
-sk_sp<SkPixelRef> SkMallocPixelRef::MakeAllocate(const SkImageInfo& info,
-                                                size_t rowBytes) {
-    auto sk_malloc_nothrow = [](size_t size) { return sk_malloc_flags(size, 0); };
-    return MakeUsing(sk_malloc_nothrow, info, rowBytes);
+sk_sp<SkPixelRef> SkMallocPixelRef::MakeAllocate(const SkImageInfo& info, size_t rowBytes) {
+    return MakeUsing(sk_malloc_canfail, info, rowBytes);
 }
 
 sk_sp<SkPixelRef> SkMallocPixelRef::MakeZeroed(const SkImageInfo& info,
                                                size_t rowBytes) {
-    return MakeUsing(sk_calloc, info, rowBytes);
+    return MakeUsing(sk_calloc_canfail, info, rowBytes);
 }
 
 static void sk_data_releaseproc(void*, void* dataPtr) {
@@ -93,8 +110,8 @@ sk_sp<SkPixelRef> SkMallocPixelRef::MakeWithProc(const SkImageInfo& info,
 }
 
 sk_sp<SkPixelRef> SkMallocPixelRef::MakeWithData(const SkImageInfo& info,
-                                                size_t rowBytes,
-                                                sk_sp<SkData> data) {
+                                                 size_t rowBytes,
+                                                 sk_sp<SkData> data) {
     SkASSERT(data != nullptr);
     if (!is_valid(info)) {
         return nullptr;