1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libs/libjpeg/jdatadst.c	Thu Sep 08 06:28:38 2011 +0300
     1.3 @@ -0,0 +1,151 @@
     1.4 +/*
     1.5 + * jdatadst.c
     1.6 + *
     1.7 + * Copyright (C) 1994-1996, Thomas G. Lane.
     1.8 + * This file is part of the Independent JPEG Group's software.
     1.9 + * For conditions of distribution and use, see the accompanying README file.
    1.10 + *
    1.11 + * This file contains compression data destination routines for the case of
    1.12 + * emitting JPEG data to a file (or any stdio stream).  While these routines
    1.13 + * are sufficient for most applications, some will want to use a different
    1.14 + * destination manager.
    1.15 + * IMPORTANT: we assume that fwrite() will correctly transcribe an array of
    1.16 + * JOCTETs into 8-bit-wide elements on external storage.  If char is wider
    1.17 + * than 8 bits on your machine, you may need to do some tweaking.
    1.18 + */
    1.19 +
    1.20 +/* this is not a core library module, so it doesn't define JPEG_INTERNALS */
    1.21 +#include "jinclude.h"
    1.22 +#include "jpeglib.h"
    1.23 +#include "jerror.h"
    1.24 +
    1.25 +
    1.26 +/* Expanded data destination object for stdio output */
    1.27 +
    1.28 +typedef struct {
    1.29 +  struct jpeg_destination_mgr pub; /* public fields */
    1.30 +
    1.31 +  FILE * outfile;		/* target stream */
    1.32 +  JOCTET * buffer;		/* start of buffer */
    1.33 +} my_destination_mgr;
    1.34 +
    1.35 +typedef my_destination_mgr * my_dest_ptr;
    1.36 +
    1.37 +#define OUTPUT_BUF_SIZE  4096	/* choose an efficiently fwrite'able size */
    1.38 +
    1.39 +
    1.40 +/*
    1.41 + * Initialize destination --- called by jpeg_start_compress
    1.42 + * before any data is actually written.
    1.43 + */
    1.44 +
    1.45 +METHODDEF(void)
    1.46 +init_destination (j_compress_ptr cinfo)
    1.47 +{
    1.48 +  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
    1.49 +
    1.50 +  /* Allocate the output buffer --- it will be released when done with image */
    1.51 +  dest->buffer = (JOCTET *)
    1.52 +      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
    1.53 +				  OUTPUT_BUF_SIZE * SIZEOF(JOCTET));
    1.54 +
    1.55 +  dest->pub.next_output_byte = dest->buffer;
    1.56 +  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
    1.57 +}
    1.58 +
    1.59 +
    1.60 +/*
    1.61 + * Empty the output buffer --- called whenever buffer fills up.
    1.62 + *
    1.63 + * In typical applications, this should write the entire output buffer
    1.64 + * (ignoring the current state of next_output_byte & free_in_buffer),
    1.65 + * reset the pointer & count to the start of the buffer, and return TRUE
    1.66 + * indicating that the buffer has been dumped.
    1.67 + *
    1.68 + * In applications that need to be able to suspend compression due to output
    1.69 + * overrun, a FALSE return indicates that the buffer cannot be emptied now.
    1.70 + * In this situation, the compressor will return to its caller (possibly with
    1.71 + * an indication that it has not accepted all the supplied scanlines).  The
    1.72 + * application should resume compression after it has made more room in the
    1.73 + * output buffer.  Note that there are substantial restrictions on the use of
    1.74 + * suspension --- see the documentation.
    1.75 + *
    1.76 + * When suspending, the compressor will back up to a convenient restart point
    1.77 + * (typically the start of the current MCU). next_output_byte & free_in_buffer
    1.78 + * indicate where the restart point will be if the current call returns FALSE.
    1.79 + * Data beyond this point will be regenerated after resumption, so do not
    1.80 + * write it out when emptying the buffer externally.
    1.81 + */
    1.82 +
    1.83 +METHODDEF(boolean)
    1.84 +empty_output_buffer (j_compress_ptr cinfo)
    1.85 +{
    1.86 +  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
    1.87 +
    1.88 +  if (JFWRITE(dest->outfile, dest->buffer, OUTPUT_BUF_SIZE) !=
    1.89 +      (size_t) OUTPUT_BUF_SIZE)
    1.90 +    ERREXIT(cinfo, JERR_FILE_WRITE);
    1.91 +
    1.92 +  dest->pub.next_output_byte = dest->buffer;
    1.93 +  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
    1.94 +
    1.95 +  return TRUE;
    1.96 +}
    1.97 +
    1.98 +
    1.99 +/*
   1.100 + * Terminate destination --- called by jpeg_finish_compress
   1.101 + * after all data has been written.  Usually needs to flush buffer.
   1.102 + *
   1.103 + * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
   1.104 + * application must deal with any cleanup that should happen even
   1.105 + * for error exit.
   1.106 + */
   1.107 +
   1.108 +METHODDEF(void)
   1.109 +term_destination (j_compress_ptr cinfo)
   1.110 +{
   1.111 +  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
   1.112 +  size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
   1.113 +
   1.114 +  /* Write any data remaining in the buffer */
   1.115 +  if (datacount > 0) {
   1.116 +    if (JFWRITE(dest->outfile, dest->buffer, datacount) != datacount)
   1.117 +      ERREXIT(cinfo, JERR_FILE_WRITE);
   1.118 +  }
   1.119 +  fflush(dest->outfile);
   1.120 +  /* Make sure we wrote the output file OK */
   1.121 +  if (ferror(dest->outfile))
   1.122 +    ERREXIT(cinfo, JERR_FILE_WRITE);
   1.123 +}
   1.124 +
   1.125 +
   1.126 +/*
   1.127 + * Prepare for output to a stdio stream.
   1.128 + * The caller must have already opened the stream, and is responsible
   1.129 + * for closing it after finishing compression.
   1.130 + */
   1.131 +
   1.132 +GLOBAL(void)
   1.133 +jpeg_stdio_dest (j_compress_ptr cinfo, FILE * outfile)
   1.134 +{
   1.135 +  my_dest_ptr dest;
   1.136 +
   1.137 +  /* The destination object is made permanent so that multiple JPEG images
   1.138 +   * can be written to the same file without re-executing jpeg_stdio_dest.
   1.139 +   * This makes it dangerous to use this manager and a different destination
   1.140 +   * manager serially with the same JPEG object, because their private object
   1.141 +   * sizes may be different.  Caveat programmer.
   1.142 +   */
   1.143 +  if (cinfo->dest == NULL) {	/* first time for this JPEG object? */
   1.144 +    cinfo->dest = (struct jpeg_destination_mgr *)
   1.145 +      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
   1.146 +				  SIZEOF(my_destination_mgr));
   1.147 +  }
   1.148 +
   1.149 +  dest = (my_dest_ptr) cinfo->dest;
   1.150 +  dest->pub.init_destination = init_destination;
   1.151 +  dest->pub.empty_output_buffer = empty_output_buffer;
   1.152 +  dest->pub.term_destination = term_destination;
   1.153 +  dest->outfile = outfile;
   1.154 +}