Handle different types of streams in different jpeg source managers
For streams that are memory backed (stream->getMemoryBase() returns
a non-null ptr and hasLength() returns true), handle the stream
with skjpeg_mem_source_mgr, which directly assigns memory base to
the source manager. For other non memory backed streams, handle the
stream with skjpeg_buffered_source_mgr, which is renamed from
the old skjpeg_source_mgr with no implementation change.
Signed-off-by: cjbao <cathy.bao@intel.com>
Bug: skia:
Change-Id: I748de0bdba726bbb318922c08497135e73e37329
Reviewed-on: https://skia-review.googlesource.com/17296
Reviewed-by: Leon Scroggins <scroggo@google.com>
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
diff --git a/src/codec/SkJpegDecoderMgr.cpp b/src/codec/SkJpegDecoderMgr.cpp
index c2837aa..0b02111 100644
--- a/src/codec/SkJpegDecoderMgr.cpp
+++ b/src/codec/SkJpegDecoderMgr.cpp
@@ -69,9 +69,13 @@
}
JpegDecoderMgr::JpegDecoderMgr(SkStream* stream)
- : fSrcMgr(stream)
- , fInit(false)
+ : fInit(false)
{
+ if(stream->getMemoryBase() && stream->hasLength()) {
+ fSrcMgr.reset(new skjpeg_mem_source_mgr(stream));
+ } else {
+ fSrcMgr.reset(new skjpeg_buffered_source_mgr(stream));
+ }
// Error manager must be set before any calls to libjeg in order to handle failures
fDInfo.err = jpeg_std_error(&fErrorMgr);
fErrorMgr.error_exit = skjpeg_err_exit;
@@ -80,7 +84,7 @@
void JpegDecoderMgr::init() {
jpeg_create_decompress(&fDInfo);
fInit = true;
- fDInfo.src = &fSrcMgr;
+ fDInfo.src = fSrcMgr.get();
fDInfo.err->output_message = &output_message;
fDInfo.progress = &fProgressMgr;
fProgressMgr.progress_monitor = &progress_monitor;
diff --git a/src/codec/SkJpegDecoderMgr.h b/src/codec/SkJpegDecoderMgr.h
index 272c5b4..20988eb 100644
--- a/src/codec/SkJpegDecoderMgr.h
+++ b/src/codec/SkJpegDecoderMgr.h
@@ -65,11 +65,11 @@
private:
- jpeg_decompress_struct fDInfo;
- skjpeg_source_mgr fSrcMgr;
- skjpeg_error_mgr fErrorMgr;
- jpeg_progress_mgr fProgressMgr;
- bool fInit;
+ jpeg_decompress_struct fDInfo;
+ std::unique_ptr<jpeg_source_mgr> fSrcMgr;
+ skjpeg_error_mgr fErrorMgr;
+ jpeg_progress_mgr fProgressMgr;
+ bool fInit;
};
#endif
diff --git a/src/codec/SkJpegUtility.cpp b/src/codec/SkJpegUtility.cpp
index 2cf36ba..b2284c8 100644
--- a/src/codec/SkJpegUtility.cpp
+++ b/src/codec/SkJpegUtility.cpp
@@ -10,10 +10,10 @@
#include "SkCodecPriv.h"
/*
- * Initialize the source manager
+ * Initialize the buffered source manager
*/
-static void sk_init_source(j_decompress_ptr dinfo) {
- skjpeg_source_mgr* src = (skjpeg_source_mgr*) dinfo->src;
+static void sk_init_buffered_source(j_decompress_ptr dinfo) {
+ skjpeg_buffered_source_mgr* src = (skjpeg_buffered_source_mgr*) dinfo->src;
src->next_input_byte = (const JOCTET*) src->fBuffer;
src->bytes_in_buffer = 0;
}
@@ -21,9 +21,9 @@
/*
* Fill the input buffer from the stream
*/
-static boolean sk_fill_input_buffer(j_decompress_ptr dinfo) {
- skjpeg_source_mgr* src = (skjpeg_source_mgr*) dinfo->src;
- size_t bytes = src->fStream->read(src->fBuffer, skjpeg_source_mgr::kBufferSize);
+static boolean sk_fill_buffered_input_buffer(j_decompress_ptr dinfo) {
+ skjpeg_buffered_source_mgr* src = (skjpeg_buffered_source_mgr*) dinfo->src;
+ size_t bytes = src->fStream->read(src->fBuffer, skjpeg_buffered_source_mgr::kBufferSize);
// libjpeg is still happy with a less than full read, as long as the result is non-zero
if (bytes == 0) {
@@ -38,8 +38,8 @@
/*
* Skip a certain number of bytes in the stream
*/
-static void sk_skip_input_data(j_decompress_ptr dinfo, long numBytes) {
- skjpeg_source_mgr* src = (skjpeg_source_mgr*) dinfo->src;
+static void sk_skip_buffered_input_data(j_decompress_ptr dinfo, long numBytes) {
+ skjpeg_buffered_source_mgr* src = (skjpeg_buffered_source_mgr*) dinfo->src;
size_t bytes = (size_t) numBytes;
if (bytes > src->bytes_in_buffer) {
@@ -73,12 +73,12 @@
* Constructor for the source manager that we provide to libjpeg
* We provide skia implementations of all of the stream processing functions required by libjpeg
*/
-skjpeg_source_mgr::skjpeg_source_mgr(SkStream* stream)
+skjpeg_buffered_source_mgr::skjpeg_buffered_source_mgr(SkStream* stream)
: fStream(stream)
{
- init_source = sk_init_source;
- fill_input_buffer = sk_fill_input_buffer;
- skip_input_data = sk_skip_input_data;
+ init_source = sk_init_buffered_source;
+ fill_input_buffer = sk_fill_buffered_input_buffer;
+ skip_input_data = sk_skip_buffered_input_data;
resync_to_restart = jpeg_resync_to_restart;
term_source = sk_term_source;
}
@@ -93,3 +93,46 @@
(*error->output_message) (dinfo);
longjmp(error->fJmpBuf, 1);
}
+
+/* memory backed source manager */
+/*
+ * Initialize the mem backed source manager
+ */
+static void sk_init_mem_source(j_decompress_ptr dinfo) {
+ /* no work necessary here, all things are done in constructor */
+}
+
+static void sk_skip_mem_input_data (j_decompress_ptr cinfo, long num_bytes) {
+ jpeg_source_mgr* src = cinfo->src;
+ size_t bytes = static_cast<size_t>(num_bytes);
+ if(bytes > src->bytes_in_buffer) {
+ src->next_input_byte = nullptr;
+ src->bytes_in_buffer = 0;
+ } else {
+ src->next_input_byte += bytes;
+ src->bytes_in_buffer -= bytes;
+ }
+}
+
+static boolean sk_fill_mem_input_buffer (j_decompress_ptr cinfo) {
+ /* The whole JPEG data is expected to reside in the supplied memory,
+ * buffer, so any request for more data beyond the given buffer size
+ * is treated as an error.
+ */
+ return false;
+}
+
+skjpeg_mem_source_mgr::skjpeg_mem_source_mgr(SkStream* stream)
+{
+ SkASSERT(stream->hasLength());
+ SkASSERT(stream->getMemoryBase());
+
+ init_source = sk_init_mem_source;
+ fill_input_buffer = sk_fill_mem_input_buffer;
+ skip_input_data = sk_skip_mem_input_data;
+ resync_to_restart = jpeg_resync_to_restart;
+ term_source = sk_term_source;
+ bytes_in_buffer = static_cast<size_t>(stream->getLength());
+ next_input_byte = static_cast<const JOCTET*>(stream->getMemoryBase());
+}
+
diff --git a/src/codec/SkJpegUtility.h b/src/codec/SkJpegUtility.h
index 33f4fbd..e5dd848 100644
--- a/src/codec/SkJpegUtility.h
+++ b/src/codec/SkJpegUtility.h
@@ -29,8 +29,8 @@
/*
* Source handling struct for that allows libjpeg to use our stream object
*/
-struct skjpeg_source_mgr : jpeg_source_mgr {
- skjpeg_source_mgr(SkStream* stream);
+struct skjpeg_buffered_source_mgr : jpeg_source_mgr {
+ skjpeg_buffered_source_mgr(SkStream* stream);
SkStream* fStream; // unowned
enum {
@@ -41,4 +41,11 @@
uint8_t fBuffer[kBufferSize];
};
+/*
+ * source for memory backed streams with a valid length
+ */
+struct skjpeg_mem_source_mgr : jpeg_source_mgr {
+ skjpeg_mem_source_mgr(SkStream* stream);
+};
+
#endif