Replace BMP calls to new with calls to malloc

A BMP can have an arbitrarily large width. We typically read a row
into a block of memory before swizzling it to the output. Rather
than calling new to create that block of memory, which may crash
when we run out of memory, call malloc, and return null if malloc
fails.

Add a common base class for Mask and Standard BMP codecs. This class
handles allocating and freeing the buffer.

Bug: b/37623797
Change-Id: I0510b76d688d030865faa481bb2fb1351dac2c97
Reviewed-on: https://skia-review.googlesource.com/18400
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/src/codec/SkBmpBaseCodec.cpp b/src/codec/SkBmpBaseCodec.cpp
new file mode 100644
index 0000000000..0e744351f0
--- /dev/null
+++ b/src/codec/SkBmpBaseCodec.cpp
@@ -0,0 +1,16 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "SkBmpBaseCodec.h"
+#include "../private/SkMalloc.h"
+
+SkBmpBaseCodec::~SkBmpBaseCodec() {}
+
+SkBmpBaseCodec::SkBmpBaseCodec(int width, int height, const SkEncodedInfo& info, SkStream* stream,
+                               uint16_t bitsPerPixel, SkCodec::SkScanlineOrder rowOrder)
+    : INHERITED(width, height, info, stream, bitsPerPixel, rowOrder)
+    , fSrcBuffer(sk_malloc_flags(this->srcRowBytes(), 0))
+{}