| Index: third_party/libvpx/source/libvpx/third_party/libyuv/source/mjpeg_validate.cc
|
| diff --git a/third_party/libvpx/source/libvpx/third_party/libyuv/source/mjpeg_validate.cc b/third_party/libvpx/source/libvpx/third_party/libyuv/source/mjpeg_validate.cc
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..40ce2f787a1a450fd70d932acaa34baf9ca1ed2a
|
| --- /dev/null
|
| +++ b/third_party/libvpx/source/libvpx/third_party/libyuv/source/mjpeg_validate.cc
|
| @@ -0,0 +1,101 @@
|
| +/*
|
| + * Copyright 2012 The LibYuv Project Authors. All rights reserved.
|
| + *
|
| + * Use of this source code is governed by a BSD-style license
|
| + * that can be found in the LICENSE file in the root of the source
|
| + * tree. An additional intellectual property rights grant can be found
|
| + * in the file PATENTS. All contributing project authors may
|
| + * be found in the AUTHORS file in the root of the source tree.
|
| + */
|
| +
|
| +#include "libyuv/mjpeg_decoder.h"
|
| +
|
| +#include <string.h> // For memchr.
|
| +
|
| +#ifdef __cplusplus
|
| +namespace libyuv {
|
| +extern "C" {
|
| +#endif
|
| +
|
| +// Enable this to try scasb implementation.
|
| +// #define ENABLE_SCASB 1
|
| +
|
| +#ifdef ENABLE_SCASB
|
| +
|
| +// Multiple of 1.
|
| +__declspec(naked) __declspec(align(16))
|
| +const uint8* ScanRow_ERMS(const uint8* src, uint32 val, int count) {
|
| + __asm {
|
| + mov edx, edi
|
| + mov edi, [esp + 4] // src
|
| + mov eax, [esp + 8] // val
|
| + mov ecx, [esp + 12] // count
|
| + repne scasb
|
| + jne sr99
|
| + mov eax, edi
|
| + sub eax, 1
|
| + mov edi, edx
|
| + ret
|
| +
|
| + sr99:
|
| + mov eax, 0
|
| + mov edi, edx
|
| + ret
|
| + }
|
| +}
|
| +#endif
|
| +
|
| +// Helper function to scan for EOI marker.
|
| +static LIBYUV_BOOL ScanEOI(const uint8* sample, size_t sample_size) {
|
| + const uint8* end = sample + sample_size - 1;
|
| + const uint8* it = sample;
|
| + for (;;) {
|
| +#ifdef ENABLE_SCASB
|
| + it = ScanRow_ERMS(it, 0xff, end - it);
|
| +#else
|
| + it = static_cast<const uint8*>(memchr(it, 0xff, end - it));
|
| +#endif
|
| + if (it == NULL) {
|
| + break;
|
| + }
|
| + if (it[1] == 0xd9) {
|
| + return LIBYUV_TRUE; // Success: Valid jpeg.
|
| + }
|
| + ++it; // Skip over current 0xff.
|
| + }
|
| + // ERROR: Invalid jpeg end code not found. Size sample_size
|
| + return LIBYUV_FALSE;
|
| +}
|
| +
|
| +// Helper function to validate the jpeg appears intact.
|
| +LIBYUV_BOOL ValidateJpeg(const uint8* sample, size_t sample_size) {
|
| + const size_t kBackSearchSize = 1024;
|
| + if (sample_size < 64) {
|
| + // ERROR: Invalid jpeg size: sample_size
|
| + return LIBYUV_FALSE;
|
| + }
|
| + if (sample[0] != 0xff || sample[1] != 0xd8) { // Start Of Image
|
| + // ERROR: Invalid jpeg initial start code
|
| + return LIBYUV_FALSE;
|
| + }
|
| + // Step over SOI marker.
|
| + sample += 2;
|
| + sample_size -= 2;
|
| +
|
| + // Look for the End Of Image (EOI) marker in the end kilobyte of the buffer.
|
| + if (sample_size > kBackSearchSize) {
|
| + if (ScanEOI(sample + sample_size - kBackSearchSize, kBackSearchSize)) {
|
| + return LIBYUV_TRUE; // Success: Valid jpeg.
|
| + }
|
| + // Reduce search size for forward search.
|
| + sample_size = sample_size - kBackSearchSize + 1;
|
| + }
|
| + return ScanEOI(sample, sample_size);
|
| +
|
| +}
|
| +
|
| +#ifdef __cplusplus
|
| +} // extern "C"
|
| +} // namespace libyuv
|
| +#endif
|
| +
|
|
|