jpeg_mem_dest.c

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//
// Copyright 2003 Sony Corporation 
//
// Permission to use, copy, modify, and redistribute this software for
// non-commercial use is hereby granted.
//
// This software is provided "as is" without warranty of any kind,
// either expressed or implied, including but not limited to the
// implied warranties of fitness for a particular purpose.
//

#include <stdio.h>
#include <jpeglib.h>
#include <jerror.h>

typedef struct {
    struct jpeg_destination_mgr pub;
    JOCTET *buf;
    size_t bufsize;
    size_t jpegsize;
} mem_destination_mgr;

typedef mem_destination_mgr *mem_dest_ptr;

METHODDEF(void) init_destination (j_compress_ptr cinfo)
{
        mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;

        dest->pub.next_output_byte = dest->buf;
        dest->pub.free_in_buffer = dest->bufsize;
    dest->jpegsize = 0;
}

METHODDEF(boolean) empty_output_buffer (j_compress_ptr cinfo)
{
    mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;
  
    dest->pub.next_output_byte = dest->buf;
    dest->pub.free_in_buffer = dest->bufsize;

    return FALSE;
    ERREXIT(cinfo, JERR_BUFFER_SIZE);
}

METHODDEF(void) term_destination(j_compress_ptr cinfo)
{
    mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;
    dest->jpegsize = dest->bufsize - dest->pub.free_in_buffer;
}

GLOBAL(void) jpeg_mem_dest (j_compress_ptr cinfo, JOCTET* buf, size_t bufsize)
{
        mem_dest_ptr dest;

        if (cinfo->dest == NULL) {
        cinfo->dest = (struct jpeg_destination_mgr *)
            (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_PERMANENT,
                                        sizeof(mem_destination_mgr));
        }

        dest = (mem_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->buf      = buf;
    dest->bufsize  = bufsize;
    dest->jpegsize = 0;
}

GLOBAL(int) jpeg_mem_size(j_compress_ptr cinfo)
{
    mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;
    return dest->jpegsize;
}

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