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📄 jpg.c

📁 MiniWinOuterSM MiniWinOuterSM
💻 C
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#include <stdio.h>
#include <memory.h>
#include <stdlib.h>
#include <malloc.h>
#include <setjmp.h>
#include "jpeglib.h"
#include "jpg.h"
struct my_error_mgr {
  struct jpeg_error_mgr pub;	/* "public" fields */
  jmp_buf setjmp_buffer;	/* for return to caller */
};

typedef struct my_error_mgr * my_error_ptr;

METHODDEF(void)
my_error_exit (j_common_ptr cinfo)
{
  /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
  my_error_ptr myerr = (my_error_ptr) cinfo->err;

  /* Always display the message. */
  /* We could postpone this until after returning, if we chose. */
  (*cinfo->err->output_message)(cinfo);

  /* Return control to the setjmp point */
  longjmp(myerr->setjmp_buffer, 1);
}

int unpack_jpg(jpg_info_t* jinfo)
{
    struct jpeg_decompress_struct cinfo;
    /* We use our private extension JPEG error handler.
     * Note that this struct must live as long as the main JPEG parameter
     * struct, to avoid dangling-pointer problems.
     */
    struct my_error_mgr jerr;
    /* More stuff */
    JSAMPARRAY buffer;		/* Output row buffer */
    int row_stride;		    /* physical row width in output buffer */
    
    cinfo.err = jpeg_std_error(&jerr.pub);
    jerr.pub.error_exit = my_error_exit;

    jpeg_create_decompress(&cinfo);

    jpeg_memory_src(&cinfo, jinfo->jpg_buffer, jinfo->jpg_buffer_length);

    jpeg_read_header(&cinfo, TRUE);
    jpeg_start_decompress(&cinfo);

    /* JSAMPLEs per row in output buffer */
    row_stride = cinfo.output_width * cinfo.output_components;
    /* Make a one-row-high sample array that will go away when done with image */
    buffer = (*cinfo.mem->alloc_sarray)
	    ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);

    jinfo->width=cinfo.output_width;
    jinfo->height=cinfo.output_height;
    jinfo->jpg_surface=(unsigned char*)malloc(jinfo->width*jinfo->height*3);

    while (cinfo.output_scanline < cinfo.output_height) {
        unsigned char* temp_src_buffer;
        unsigned char* temp_des_buffer;

        jpeg_read_scanlines(&cinfo, buffer, 1);

        temp_src_buffer=(unsigned char*)(*buffer);
        temp_des_buffer=jinfo->jpg_surface+jinfo->width*(cinfo.output_scanline-1)*3;

        memcpy(temp_des_buffer,temp_src_buffer,row_stride);
    }

    jpeg_finish_decompress(&cinfo);
    jpeg_destroy_decompress(&cinfo);
    return 0;
}

int destroy_jpg(jpg_info_t* jinfo)
{
    if (jinfo->jpg_surface!=NULL) {
        free(jinfo->jpg_surface);
    }
    return 0;
}


#ifndef EXIT_FAILURE		/* define exit() codes if not provided */
#define EXIT_FAILURE  1
#endif


/*
 * Create the message string table.
 * We do this from the master message list in jerror.h by re-reading
 * jerror.h with a suitable definition for macro JMESSAGE.
 * The message table is made an external symbol just in case any applications
 * want to refer to it directly.
 */

#define JMESSAGE(code,string)	string ,

const char * const jpeg_std_message_table[] = {
#include "jpg.h"
  NULL
};


/*
 * Error exit handler: must not return to caller.
 *
 * Applications may override this if they want to get control back after
 * an error.  Typically one would longjmp somewhere instead of exiting.
 * The setjmp buffer can be made a private field within an expanded error
 * handler object.  Note that the info needed to generate an error message
 * is stored in the error object, so you can generate the message now or
 * later, at your convenience.
 * You should make sure that the JPEG object is cleaned up (with jpeg_abort
 * or jpeg_destroy) at some point.
 */

METHODDEF(void)
error_exit (j_common_ptr cinfo)
{
  /* Always display the message */
  (*cinfo->err->output_message) (cinfo);

  /* Let the memory manager delete any temp files before we die */
  jpeg_destroy(cinfo);

}


/*
 * Actual output of an error or trace message.
 * Applications may override this method to send JPEG messages somewhere
 * other than stderr.
 */

METHODDEF(void)
output_message (j_common_ptr cinfo)
{
  char buffer[JMSG_LENGTH_MAX];

  /* Create the message */
  (*cinfo->err->format_message) (cinfo, buffer);

  /* Send it to stderr, adding a newline */
  fprintf(stderr, "%s\n", buffer);
}


/*
 * Decide whether to emit a trace or warning message.
 * msg_level is one of:
 *   -1: recoverable corrupt-data warning, may want to abort.
 *    0: important advisory messages (always display to user).
 *    1: first level of tracing detail.
 *    2,3,...: successively more detailed tracing messages.
 * An application might override this method if it wanted to abort on warnings
 * or change the policy about which messages to display.
 */

METHODDEF(void)
emit_message (j_common_ptr cinfo, int msg_level)
{
  struct jpeg_error_mgr * err = cinfo->err;

  if (msg_level < 0) {
    /* It's a warning message.  Since corrupt files may generate many warnings,
     * the policy implemented here is to show only the first warning,
     * unless trace_level >= 3.
     */
    if (err->num_warnings == 0 || err->trace_level >= 3)
      (*err->output_message) (cinfo);
    /* Always count warnings in num_warnings. */
    err->num_warnings++;
  } else {
    /* It's a trace message.  Show it if trace_level >= msg_level. */
    if (err->trace_level >= msg_level)
      (*err->output_message) (cinfo);
  }
}


/*
 * Format a message string for the most recent JPEG error or message.
 * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX
 * characters.  Note that no '\n' character is added to the string.
 * Few applications should need to override this method.
 */

METHODDEF(void)
format_message (j_common_ptr cinfo, char * buffer)
{
  struct jpeg_error_mgr * err = cinfo->err;
  int msg_code = err->msg_code;
  const char * msgtext = NULL;
  const char * msgptr;
  char ch;
  boolean isstring;

  /* Look up message string in proper table */
  if (msg_code > 0 && msg_code <= err->last_jpeg_message) {
    msgtext = err->jpeg_message_table[msg_code];
  } else if (err->addon_message_table != NULL &&
	     msg_code >= err->first_addon_message &&
	     msg_code <= err->last_addon_message) {
    msgtext = err->addon_message_table[msg_code - err->first_addon_message];
  }

  /* Defend against bogus message number */
  if (msgtext == NULL) {
    err->msg_parm.i[0] = msg_code;
    msgtext = err->jpeg_message_table[0];
  }

  /* Check for string parameter, as indicated by %s in the message text */
  isstring = FALSE;
  msgptr = msgtext;
  while ((ch = *msgptr++) != '\0') {
    if (ch == '%') {
      if (*msgptr == 's') isstring = TRUE;
      break;
    }
  }

  /* Format the message into the passed buffer */
  if (isstring)
    sprintf(buffer, msgtext, err->msg_parm.s);
  else
    sprintf(buffer, msgtext,
	    err->msg_parm.i[0], err->msg_parm.i[1],
	    err->msg_parm.i[2], err->msg_parm.i[3],
	    err->msg_parm.i[4], err->msg_parm.i[5],
	    err->msg_parm.i[6], err->msg_parm.i[7]);
}


/*
 * Reset error state variables at start of a new image.
 * This is called during compression startup to reset trace/error
 * processing to default state, without losing any application-specific
 * method pointers.  An application might possibly want to override
 * this method if it has additional error processing state.
 */

METHODDEF(void)
reset_error_mgr (j_common_ptr cinfo)
{
  cinfo->err->num_warnings = 0;
  /* trace_level is not reset since it is an application-supplied parameter */
  cinfo->err->msg_code = 0;	/* may be useful as a flag for "no error" */
}


/*
 * Fill in the standard error-handling methods in a jpeg_error_mgr object.
 * Typical call is:
 *	struct jpeg_compress_struct cinfo;
 *	struct jpeg_error_mgr err;
 *
 *	cinfo.err = jpeg_std_error(&err);
 * after which the application may override some of the methods.
 */

GLOBAL(struct jpeg_error_mgr *)
jpeg_std_error (struct jpeg_error_mgr * err)
{
  err->error_exit = error_exit;
  err->emit_message = emit_message;
  err->output_message = output_message;
  err->format_message = format_message;
  err->reset_error_mgr = reset_error_mgr;

  err->trace_level = 0;		/* default = no tracing */
  err->num_warnings = 0;	/* no warnings emitted yet */
  err->msg_code = 0;		/* may be useful as a flag for "no error" */

  /* Initialize message table pointers */
  err->jpeg_message_table = jpeg_std_message_table;
  err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;

  err->addon_message_table = NULL;
  err->first_addon_message = 0;	/* for safety */
  err->last_addon_message = 0;

  return err;
}

#define JPEG_INTERNALS
#include "jpegint.h"
#define AM_MEMORY_MANAGER	/* we define jvirt_Xarray_control structs */

#ifndef NO_GETENV
#ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare getenv() */
extern char * getenv JPP((const char * name));
#endif
#endif


/*
 * Some important notes:
 *   The allocation routines provided here must never return NULL.
 *   They should exit to error_exit if unsuccessful.
 *
 *   It's not a good idea to try to merge the sarray and barray routines,
 *   even though they are textually almost the same, because samples are
 *   usually stored as bytes while coefficients are shorts or ints.  Thus,
 *   in machines where byte pointers have a different representation from
 *   word pointers, the resulting machine code could not be the same.
 */


/*
 * Many machines require storage alignment: longs must start on 4-byte
 * boundaries, doubles on 8-byte boundaries, etc.  On such machines, malloc()
 * always returns pointers that are multiples of the worst-case alignment
 * requirement, and we had better do so too.
 * There isn't any really portable way to determine the worst-case alignment
 * requirement.  This module assumes that the alignment requirement is
 * multiples of sizeof(ALIGN_TYPE).
 * By default, we define ALIGN_TYPE as double.  This is necessary on some
 * workstations (where doubles really do need 8-byte alignment) and will work
 * fine on nearly everything.  If your machine has lesser alignment needs,
 * you can save a few bytes by making ALIGN_TYPE smaller.
 * The only place I know of where this will NOT work is certain Macintosh
 * 680x0 compilers that define double as a 10-byte IEEE extended float.
 * Doing 10-byte alignment is counterproductive because longwords won't be
 * aligned well.  Put "#define ALIGN_TYPE long" in jconfig.h if you have
 * such a compiler.
 */

#ifndef ALIGN_TYPE		/* so can override from jconfig.h */
#define ALIGN_TYPE  double
#endif


/*
 * We allocate objects from "pools", where each pool is gotten with a single
 * request to jpeg_get_small() or jpeg_get_large().  There is no per-object
 * overhead within a pool, except for alignment padding.  Each pool has a
 * header with a link to the next pool of the same class.
 * Small and large pool headers are identical except that the latter's
 * link pointer must be FAR on 80x86 machines.
 * Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE
 * field.  This forces the compiler to make SIZEOF(small_pool_hdr) a multiple
 * of the alignment requirement of ALIGN_TYPE.
 */

typedef union small_pool_struct * small_pool_ptr;

typedef union small_pool_struct {
  struct {
    small_pool_ptr next;	/* next in list of pools */
    size_t bytes_used;		/* how many bytes already used within pool */
    size_t bytes_left;		/* bytes still available in this pool */
  } hdr;
  ALIGN_TYPE dummy;		/* included in union to ensure alignment */
} small_pool_hdr;

typedef union large_pool_struct * large_pool_ptr;

typedef union large_pool_struct {
  struct {
    large_pool_ptr next;	/* next in list of pools */
    size_t bytes_used;		/* how many bytes already used within pool */
    size_t bytes_left;		/* bytes still available in this pool */

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