michael@0: /*
michael@0:  * Copyright 2010 The Android Open Source Project
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkJpegUtility.h"
michael@0: 
michael@0: /////////////////////////////////////////////////////////////////////
michael@0: static void sk_init_source(j_decompress_ptr cinfo) {
michael@0:     skjpeg_source_mgr*  src = (skjpeg_source_mgr*)cinfo->src;
michael@0:     src->next_input_byte = (const JOCTET*)src->fBuffer;
michael@0:     src->bytes_in_buffer = 0;
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0:     src->current_offset = 0;
michael@0: #endif
michael@0:     if (!src->fStream->rewind()) {
michael@0:         SkDebugf("xxxxxxxxxxxxxx failure to rewind\n");
michael@0:         cinfo->err->error_exit((j_common_ptr)cinfo);
michael@0:     }
michael@0: }
michael@0: 
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0: static boolean sk_seek_input_data(j_decompress_ptr cinfo, long byte_offset) {
michael@0:     skjpeg_source_mgr* src = (skjpeg_source_mgr*)cinfo->src;
michael@0:     size_t bo = (size_t) byte_offset;
michael@0: 
michael@0:     if (bo > src->current_offset) {
michael@0:         (void)src->fStream->skip(bo - src->current_offset);
michael@0:     } else {
michael@0:         if (!src->fStream->rewind()) {
michael@0:             SkDebugf("xxxxxxxxxxxxxx failure to rewind\n");
michael@0:             cinfo->err->error_exit((j_common_ptr)cinfo);
michael@0:             return false;
michael@0:         }
michael@0:         (void)src->fStream->skip(bo);
michael@0:     }
michael@0: 
michael@0:     src->current_offset = bo;
michael@0:     src->next_input_byte = (const JOCTET*)src->fBuffer;
michael@0:     src->bytes_in_buffer = 0;
michael@0:     return true;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: static boolean sk_fill_input_buffer(j_decompress_ptr cinfo) {
michael@0:     skjpeg_source_mgr* src = (skjpeg_source_mgr*)cinfo->src;
michael@0:     if (src->fDecoder != NULL && src->fDecoder->shouldCancelDecode()) {
michael@0:         return FALSE;
michael@0:     }
michael@0:     size_t bytes = src->fStream->read(src->fBuffer, skjpeg_source_mgr::kBufferSize);
michael@0:     // note that JPEG is happy with less than the full read,
michael@0:     // as long as the result is non-zero
michael@0:     if (bytes == 0) {
michael@0:         return FALSE;
michael@0:     }
michael@0: 
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0:     src->current_offset += bytes;
michael@0: #endif
michael@0:     src->next_input_byte = (const JOCTET*)src->fBuffer;
michael@0:     src->bytes_in_buffer = bytes;
michael@0:     return TRUE;
michael@0: }
michael@0: 
michael@0: static void sk_skip_input_data(j_decompress_ptr cinfo, long num_bytes) {
michael@0:     skjpeg_source_mgr*  src = (skjpeg_source_mgr*)cinfo->src;
michael@0: 
michael@0:     if (num_bytes > (long)src->bytes_in_buffer) {
michael@0:         size_t bytesToSkip = num_bytes - src->bytes_in_buffer;
michael@0:         while (bytesToSkip > 0) {
michael@0:             size_t bytes = src->fStream->skip(bytesToSkip);
michael@0:             if (bytes <= 0 || bytes > bytesToSkip) {
michael@0: //              SkDebugf("xxxxxxxxxxxxxx failure to skip request %d returned %d\n", bytesToSkip, bytes);
michael@0:                 cinfo->err->error_exit((j_common_ptr)cinfo);
michael@0:                 return;
michael@0:             }
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0:             src->current_offset += bytes;
michael@0: #endif
michael@0:             bytesToSkip -= bytes;
michael@0:         }
michael@0:         src->next_input_byte = (const JOCTET*)src->fBuffer;
michael@0:         src->bytes_in_buffer = 0;
michael@0:     } else {
michael@0:         src->next_input_byte += num_bytes;
michael@0:         src->bytes_in_buffer -= num_bytes;
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void sk_term_source(j_decompress_ptr /*cinfo*/) {}
michael@0: 
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: skjpeg_source_mgr::skjpeg_source_mgr(SkStream* stream, SkImageDecoder* decoder)
michael@0:     : fStream(SkRef(stream))
michael@0:     , fDecoder(decoder) {
michael@0: 
michael@0:     init_source = sk_init_source;
michael@0:     fill_input_buffer = sk_fill_input_buffer;
michael@0:     skip_input_data = sk_skip_input_data;
michael@0:     resync_to_restart = jpeg_resync_to_restart;
michael@0:     term_source = sk_term_source;
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0:     seek_input_data = sk_seek_input_data;
michael@0: #endif
michael@0: //    SkDebugf("**************** use memorybase %p %d\n", fMemoryBase, fMemoryBaseSize);
michael@0: }
michael@0: 
michael@0: skjpeg_source_mgr::~skjpeg_source_mgr() {
michael@0:     SkSafeUnref(fStream);
michael@0: }
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: static void sk_init_destination(j_compress_ptr cinfo) {
michael@0:     skjpeg_destination_mgr* dest = (skjpeg_destination_mgr*)cinfo->dest;
michael@0: 
michael@0:     dest->next_output_byte = dest->fBuffer;
michael@0:     dest->free_in_buffer = skjpeg_destination_mgr::kBufferSize;
michael@0: }
michael@0: 
michael@0: static boolean sk_empty_output_buffer(j_compress_ptr cinfo) {
michael@0:     skjpeg_destination_mgr* dest = (skjpeg_destination_mgr*)cinfo->dest;
michael@0: 
michael@0: //  if (!dest->fStream->write(dest->fBuffer, skjpeg_destination_mgr::kBufferSize - dest->free_in_buffer))
michael@0:     if (!dest->fStream->write(dest->fBuffer,
michael@0:             skjpeg_destination_mgr::kBufferSize)) {
michael@0:         ERREXIT(cinfo, JERR_FILE_WRITE);
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     dest->next_output_byte = dest->fBuffer;
michael@0:     dest->free_in_buffer = skjpeg_destination_mgr::kBufferSize;
michael@0:     return TRUE;
michael@0: }
michael@0: 
michael@0: static void sk_term_destination (j_compress_ptr cinfo) {
michael@0:     skjpeg_destination_mgr* dest = (skjpeg_destination_mgr*)cinfo->dest;
michael@0: 
michael@0:     size_t size = skjpeg_destination_mgr::kBufferSize - dest->free_in_buffer;
michael@0:     if (size > 0) {
michael@0:         if (!dest->fStream->write(dest->fBuffer, size)) {
michael@0:             ERREXIT(cinfo, JERR_FILE_WRITE);
michael@0:             return;
michael@0:         }
michael@0:     }
michael@0:     dest->fStream->flush();
michael@0: }
michael@0: 
michael@0: skjpeg_destination_mgr::skjpeg_destination_mgr(SkWStream* stream)
michael@0:         : fStream(stream) {
michael@0:     this->init_destination = sk_init_destination;
michael@0:     this->empty_output_buffer = sk_empty_output_buffer;
michael@0:     this->term_destination = sk_term_destination;
michael@0: }
michael@0: 
michael@0: void skjpeg_error_exit(j_common_ptr cinfo) {
michael@0:     skjpeg_error_mgr* error = (skjpeg_error_mgr*)cinfo->err;
michael@0: 
michael@0:     (*error->output_message) (cinfo);
michael@0: 
michael@0:     /* Let the memory manager delete any temp files before we die */
michael@0:     jpeg_destroy(cinfo);
michael@0: 
michael@0:     longjmp(error->fJmpBuf, -1);
michael@0: }