Index: third_party/libjpeg_turbo/jdatadst.c |
=================================================================== |
--- third_party/libjpeg_turbo/jdatadst.c (revision 0) |
+++ third_party/libjpeg_turbo/jdatadst.c (revision 0) |
@@ -0,0 +1,151 @@ |
+/* |
+ * jdatadst.c |
+ * |
+ * Copyright (C) 1994-1996, Thomas G. Lane. |
+ * This file is part of the Independent JPEG Group's software. |
+ * For conditions of distribution and use, see the accompanying README file. |
+ * |
+ * This file contains compression data destination routines for the case of |
+ * emitting JPEG data to a file (or any stdio stream). While these routines |
+ * are sufficient for most applications, some will want to use a different |
+ * destination manager. |
+ * IMPORTANT: we assume that fwrite() will correctly transcribe an array of |
+ * JOCTETs into 8-bit-wide elements on external storage. If char is wider |
+ * than 8 bits on your machine, you may need to do some tweaking. |
+ */ |
+ |
+/* this is not a core library module, so it doesn't define JPEG_INTERNALS */ |
+#include "jinclude.h" |
+#include "jpeglib.h" |
+#include "jerror.h" |
+ |
+ |
+/* Expanded data destination object for stdio output */ |
+ |
+typedef struct { |
+ struct jpeg_destination_mgr pub; /* public fields */ |
+ |
+ FILE * outfile; /* target stream */ |
+ JOCTET * buffer; /* start of buffer */ |
+} my_destination_mgr; |
+ |
+typedef my_destination_mgr * my_dest_ptr; |
+ |
+#define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */ |
+ |
+ |
+/* |
+ * Initialize destination --- called by jpeg_start_compress |
+ * before any data is actually written. |
+ */ |
+ |
+METHODDEF(void) |
+init_destination (j_compress_ptr cinfo) |
+{ |
+ my_dest_ptr dest = (my_dest_ptr) cinfo->dest; |
+ |
+ /* Allocate the output buffer --- it will be released when done with image */ |
+ dest->buffer = (JOCTET *) |
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, |
+ OUTPUT_BUF_SIZE * SIZEOF(JOCTET)); |
+ |
+ dest->pub.next_output_byte = dest->buffer; |
+ dest->pub.free_in_buffer = OUTPUT_BUF_SIZE; |
+} |
+ |
+ |
+/* |
+ * Empty the output buffer --- called whenever buffer fills up. |
+ * |
+ * In typical applications, this should write the entire output buffer |
+ * (ignoring the current state of next_output_byte & free_in_buffer), |
+ * reset the pointer & count to the start of the buffer, and return TRUE |
+ * indicating that the buffer has been dumped. |
+ * |
+ * In applications that need to be able to suspend compression due to output |
+ * overrun, a FALSE return indicates that the buffer cannot be emptied now. |
+ * In this situation, the compressor will return to its caller (possibly with |
+ * an indication that it has not accepted all the supplied scanlines). The |
+ * application should resume compression after it has made more room in the |
+ * output buffer. Note that there are substantial restrictions on the use of |
+ * suspension --- see the documentation. |
+ * |
+ * When suspending, the compressor will back up to a convenient restart point |
+ * (typically the start of the current MCU). next_output_byte & free_in_buffer |
+ * indicate where the restart point will be if the current call returns FALSE. |
+ * Data beyond this point will be regenerated after resumption, so do not |
+ * write it out when emptying the buffer externally. |
+ */ |
+ |
+METHODDEF(boolean) |
+empty_output_buffer (j_compress_ptr cinfo) |
+{ |
+ my_dest_ptr dest = (my_dest_ptr) cinfo->dest; |
+ |
+ if (JFWRITE(dest->outfile, dest->buffer, OUTPUT_BUF_SIZE) != |
+ (size_t) OUTPUT_BUF_SIZE) |
+ ERREXIT(cinfo, JERR_FILE_WRITE); |
+ |
+ dest->pub.next_output_byte = dest->buffer; |
+ dest->pub.free_in_buffer = OUTPUT_BUF_SIZE; |
+ |
+ return TRUE; |
+} |
+ |
+ |
+/* |
+ * Terminate destination --- called by jpeg_finish_compress |
+ * after all data has been written. Usually needs to flush buffer. |
+ * |
+ * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding |
+ * application must deal with any cleanup that should happen even |
+ * for error exit. |
+ */ |
+ |
+METHODDEF(void) |
+term_destination (j_compress_ptr cinfo) |
+{ |
+ my_dest_ptr dest = (my_dest_ptr) cinfo->dest; |
+ size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer; |
+ |
+ /* Write any data remaining in the buffer */ |
+ if (datacount > 0) { |
+ if (JFWRITE(dest->outfile, dest->buffer, datacount) != datacount) |
+ ERREXIT(cinfo, JERR_FILE_WRITE); |
+ } |
+ fflush(dest->outfile); |
+ /* Make sure we wrote the output file OK */ |
+ if (ferror(dest->outfile)) |
+ ERREXIT(cinfo, JERR_FILE_WRITE); |
+} |
+ |
+ |
+/* |
+ * Prepare for output to a stdio stream. |
+ * The caller must have already opened the stream, and is responsible |
+ * for closing it after finishing compression. |
+ */ |
+ |
+GLOBAL(void) |
+jpeg_stdio_dest (j_compress_ptr cinfo, FILE * outfile) |
+{ |
+ my_dest_ptr dest; |
+ |
+ /* The destination object is made permanent so that multiple JPEG images |
+ * can be written to the same file without re-executing jpeg_stdio_dest. |
+ * This makes it dangerous to use this manager and a different destination |
+ * manager serially with the same JPEG object, because their private object |
+ * sizes may be different. Caveat programmer. |
+ */ |
+ if (cinfo->dest == NULL) { /* first time for this JPEG object? */ |
+ cinfo->dest = (struct jpeg_destination_mgr *) |
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, |
+ SIZEOF(my_destination_mgr)); |
+ } |
+ |
+ dest = (my_dest_ptr) cinfo->dest; |
+ dest->pub.init_destination = init_destination; |
+ dest->pub.empty_output_buffer = empty_output_buffer; |
+ dest->pub.term_destination = term_destination; |
+ dest->outfile = outfile; |
+} |