Move is_orientation_marker into its own file
Bug: skia:8046
This is used both by SkJpegCodec and SkWebpCodec, so make it possible
to use it when SK_HAS_JPEG_LIBRARY is not set.
Change-Id: I34aa3587500cca3d2d74c4eb33945451592bf72b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/175428
Commit-Queue: Leon Scroggins <scroggo@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/src/codec/SkJpegCodec.cpp b/src/codec/SkJpegCodec.cpp
index c8adb5c..45bd35d 100644
--- a/src/codec/SkJpegCodec.cpp
+++ b/src/codec/SkJpegCodec.cpp
@@ -15,6 +15,7 @@
#include "include/private/SkTo.h"
#include "src/codec/SkCodecPriv.h"
#include "src/codec/SkJpegDecoderMgr.h"
+#include "src/codec/SkParseEncodedOrigin.h"
#include "src/pdf/SkJpegInfo.h"
// stdio is needed for libjpeg-turbo
@@ -36,14 +37,6 @@
return bytesRead >= 3 && !memcmp(buffer, jpegSig, sizeof(jpegSig));
}
-static uint32_t get_endian_int(const uint8_t* data, bool littleEndian) {
- if (littleEndian) {
- return (data[3] << 24) | (data[2] << 16) | (data[1] << 8) | (data[0]);
- }
-
- return (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | (data[3]);
-}
-
const uint32_t kExifHeaderSize = 14;
const uint32_t kExifMarker = JPEG_APP0 + 1;
@@ -59,53 +52,10 @@
// Account for 'E', 'x', 'i', 'f', '\0', '<fill byte>'.
constexpr size_t kOffset = 6;
- return is_orientation_marker(marker->data + kOffset, marker->data_length - kOffset,
+ return SkParseEncodedOrigin(marker->data + kOffset, marker->data_length - kOffset,
orientation);
}
-bool is_orientation_marker(const uint8_t* data, size_t data_length, SkEncodedOrigin* orientation) {
- bool littleEndian;
- // We need eight bytes to read the endian marker and the offset, below.
- if (data_length < 8 || !is_valid_endian_marker(data, &littleEndian)) {
- return false;
- }
-
- // Get the offset from the start of the marker.
- // Though this only reads four bytes, use a larger int in case it overflows.
- uint64_t offset = get_endian_int(data + 4, littleEndian);
-
- // Require that the marker is at least large enough to contain the number of entries.
- if (data_length < offset + 2) {
- return false;
- }
- uint32_t numEntries = get_endian_short(data + offset, littleEndian);
-
- // Tag (2 bytes), Datatype (2 bytes), Number of elements (4 bytes), Data (4 bytes)
- const uint32_t kEntrySize = 12;
- const auto max = SkTo<uint32_t>((data_length - offset - 2) / kEntrySize);
- numEntries = SkTMin(numEntries, max);
-
- // Advance the data to the start of the entries.
- data += offset + 2;
-
- const uint16_t kOriginTag = 0x112;
- const uint16_t kOriginType = 3;
- for (uint32_t i = 0; i < numEntries; i++, data += kEntrySize) {
- uint16_t tag = get_endian_short(data, littleEndian);
- uint16_t type = get_endian_short(data + 2, littleEndian);
- uint32_t count = get_endian_int(data + 4, littleEndian);
- if (kOriginTag == tag && kOriginType == type && 1 == count) {
- uint16_t val = get_endian_short(data + 8, littleEndian);
- if (0 < val && val <= kLast_SkEncodedOrigin) {
- *orientation = (SkEncodedOrigin) val;
- return true;
- }
- }
- }
-
- return false;
-}
-
static SkEncodedOrigin get_exif_orientation(jpeg_decompress_struct* dinfo) {
SkEncodedOrigin orientation;
for (jpeg_marker_struct* marker = dinfo->marker_list; marker; marker = marker->next) {