michael@0: /*
michael@0:  * jerror.c
michael@0:  *
michael@0:  * Copyright (C) 1991-1998, Thomas G. Lane.
michael@0:  * This file is part of the Independent JPEG Group's software.
michael@0:  * For conditions of distribution and use, see the accompanying README file.
michael@0:  *
michael@0:  * This file contains simple error-reporting and trace-message routines.
michael@0:  * These are suitable for Unix-like systems and others where writing to
michael@0:  * stderr is the right thing to do.  Many applications will want to replace
michael@0:  * some or all of these routines.
michael@0:  *
michael@0:  * If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile,
michael@0:  * you get a Windows-specific hack to display error messages in a dialog box.
michael@0:  * It ain't much, but it beats dropping error messages into the bit bucket,
michael@0:  * which is what happens to output to stderr under most Windows C compilers.
michael@0:  *
michael@0:  * These routines are used by both the compression and decompression code.
michael@0:  */
michael@0: 
michael@0: /* this is not a core library module, so it doesn't define JPEG_INTERNALS */
michael@0: #include "jinclude.h"
michael@0: #include "jpeglib.h"
michael@0: #include "jversion.h"
michael@0: #include "jerror.h"
michael@0: 
michael@0: #ifdef USE_WINDOWS_MESSAGEBOX
michael@0: #include <windows.h>
michael@0: #endif
michael@0: 
michael@0: #ifndef EXIT_FAILURE		/* define exit() codes if not provided */
michael@0: #define EXIT_FAILURE  1
michael@0: #endif
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Create the message string table.
michael@0:  * We do this from the master message list in jerror.h by re-reading
michael@0:  * jerror.h with a suitable definition for macro JMESSAGE.
michael@0:  * The message table is made an external symbol just in case any applications
michael@0:  * want to refer to it directly.
michael@0:  */
michael@0: 
michael@0: #ifdef NEED_SHORT_EXTERNAL_NAMES
michael@0: #define jpeg_std_message_table	jMsgTable
michael@0: #endif
michael@0: 
michael@0: #define JMESSAGE(code,string)	string ,
michael@0: 
michael@0: const char * const jpeg_std_message_table[] = {
michael@0: #include "jerror.h"
michael@0:   NULL
michael@0: };
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Error exit handler: must not return to caller.
michael@0:  *
michael@0:  * Applications may override this if they want to get control back after
michael@0:  * an error.  Typically one would longjmp somewhere instead of exiting.
michael@0:  * The setjmp buffer can be made a private field within an expanded error
michael@0:  * handler object.  Note that the info needed to generate an error message
michael@0:  * is stored in the error object, so you can generate the message now or
michael@0:  * later, at your convenience.
michael@0:  * You should make sure that the JPEG object is cleaned up (with jpeg_abort
michael@0:  * or jpeg_destroy) at some point.
michael@0:  */
michael@0: 
michael@0: METHODDEF(void)
michael@0: error_exit (j_common_ptr cinfo)
michael@0: {
michael@0:   /* Always display the message */
michael@0:   (*cinfo->err->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:   exit(EXIT_FAILURE);
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Actual output of an error or trace message.
michael@0:  * Applications may override this method to send JPEG messages somewhere
michael@0:  * other than stderr.
michael@0:  *
michael@0:  * On Windows, printing to stderr is generally completely useless,
michael@0:  * so we provide optional code to produce an error-dialog popup.
michael@0:  * Most Windows applications will still prefer to override this routine,
michael@0:  * but if they don't, it'll do something at least marginally useful.
michael@0:  *
michael@0:  * NOTE: to use the library in an environment that doesn't support the
michael@0:  * C stdio library, you may have to delete the call to fprintf() entirely,
michael@0:  * not just not use this routine.
michael@0:  */
michael@0: 
michael@0: METHODDEF(void)
michael@0: output_message (j_common_ptr cinfo)
michael@0: {
michael@0:   char buffer[JMSG_LENGTH_MAX];
michael@0: 
michael@0:   /* Create the message */
michael@0:   (*cinfo->err->format_message) (cinfo, buffer);
michael@0: 
michael@0: #ifdef USE_WINDOWS_MESSAGEBOX
michael@0:   /* Display it in a message dialog box */
michael@0:   MessageBox(GetActiveWindow(), buffer, "JPEG Library Error",
michael@0: 	     MB_OK | MB_ICONERROR);
michael@0: #else
michael@0:   /* Send it to stderr, adding a newline */
michael@0:   fprintf(stderr, "%s\n", buffer);
michael@0: #endif
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Decide whether to emit a trace or warning message.
michael@0:  * msg_level is one of:
michael@0:  *   -1: recoverable corrupt-data warning, may want to abort.
michael@0:  *    0: important advisory messages (always display to user).
michael@0:  *    1: first level of tracing detail.
michael@0:  *    2,3,...: successively more detailed tracing messages.
michael@0:  * An application might override this method if it wanted to abort on warnings
michael@0:  * or change the policy about which messages to display.
michael@0:  */
michael@0: 
michael@0: METHODDEF(void)
michael@0: emit_message (j_common_ptr cinfo, int msg_level)
michael@0: {
michael@0:   struct jpeg_error_mgr * err = cinfo->err;
michael@0: 
michael@0:   if (msg_level < 0) {
michael@0:     /* It's a warning message.  Since corrupt files may generate many warnings,
michael@0:      * the policy implemented here is to show only the first warning,
michael@0:      * unless trace_level >= 3.
michael@0:      */
michael@0:     if (err->num_warnings == 0 || err->trace_level >= 3)
michael@0:       (*err->output_message) (cinfo);
michael@0:     /* Always count warnings in num_warnings. */
michael@0:     err->num_warnings++;
michael@0:   } else {
michael@0:     /* It's a trace message.  Show it if trace_level >= msg_level. */
michael@0:     if (err->trace_level >= msg_level)
michael@0:       (*err->output_message) (cinfo);
michael@0:   }
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Format a message string for the most recent JPEG error or message.
michael@0:  * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX
michael@0:  * characters.  Note that no '\n' character is added to the string.
michael@0:  * Few applications should need to override this method.
michael@0:  */
michael@0: 
michael@0: METHODDEF(void)
michael@0: format_message (j_common_ptr cinfo, char * buffer)
michael@0: {
michael@0:   struct jpeg_error_mgr * err = cinfo->err;
michael@0:   int msg_code = err->msg_code;
michael@0:   const char * msgtext = NULL;
michael@0:   const char * msgptr;
michael@0:   char ch;
michael@0:   boolean isstring;
michael@0: 
michael@0:   /* Look up message string in proper table */
michael@0:   if (msg_code > 0 && msg_code <= err->last_jpeg_message) {
michael@0:     msgtext = err->jpeg_message_table[msg_code];
michael@0:   } else if (err->addon_message_table != NULL &&
michael@0: 	     msg_code >= err->first_addon_message &&
michael@0: 	     msg_code <= err->last_addon_message) {
michael@0:     msgtext = err->addon_message_table[msg_code - err->first_addon_message];
michael@0:   }
michael@0: 
michael@0:   /* Defend against bogus message number */
michael@0:   if (msgtext == NULL) {
michael@0:     err->msg_parm.i[0] = msg_code;
michael@0:     msgtext = err->jpeg_message_table[0];
michael@0:   }
michael@0: 
michael@0:   /* Check for string parameter, as indicated by %s in the message text */
michael@0:   isstring = FALSE;
michael@0:   msgptr = msgtext;
michael@0:   while ((ch = *msgptr++) != '\0') {
michael@0:     if (ch == '%') {
michael@0:       if (*msgptr == 's') isstring = TRUE;
michael@0:       break;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   /* Format the message into the passed buffer */
michael@0:   if (isstring)
michael@0:     sprintf(buffer, msgtext, err->msg_parm.s);
michael@0:   else
michael@0:     sprintf(buffer, msgtext,
michael@0: 	    err->msg_parm.i[0], err->msg_parm.i[1],
michael@0: 	    err->msg_parm.i[2], err->msg_parm.i[3],
michael@0: 	    err->msg_parm.i[4], err->msg_parm.i[5],
michael@0: 	    err->msg_parm.i[6], err->msg_parm.i[7]);
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Reset error state variables at start of a new image.
michael@0:  * This is called during compression startup to reset trace/error
michael@0:  * processing to default state, without losing any application-specific
michael@0:  * method pointers.  An application might possibly want to override
michael@0:  * this method if it has additional error processing state.
michael@0:  */
michael@0: 
michael@0: METHODDEF(void)
michael@0: reset_error_mgr (j_common_ptr cinfo)
michael@0: {
michael@0:   cinfo->err->num_warnings = 0;
michael@0:   /* trace_level is not reset since it is an application-supplied parameter */
michael@0:   cinfo->err->msg_code = 0;	/* may be useful as a flag for "no error" */
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * Fill in the standard error-handling methods in a jpeg_error_mgr object.
michael@0:  * Typical call is:
michael@0:  *	struct jpeg_compress_struct cinfo;
michael@0:  *	struct jpeg_error_mgr err;
michael@0:  *
michael@0:  *	cinfo.err = jpeg_std_error(&err);
michael@0:  * after which the application may override some of the methods.
michael@0:  */
michael@0: 
michael@0: GLOBAL(struct jpeg_error_mgr *)
michael@0: jpeg_std_error (struct jpeg_error_mgr * err)
michael@0: {
michael@0:   err->error_exit = error_exit;
michael@0:   err->emit_message = emit_message;
michael@0:   err->output_message = output_message;
michael@0:   err->format_message = format_message;
michael@0:   err->reset_error_mgr = reset_error_mgr;
michael@0: 
michael@0:   err->trace_level = 0;		/* default = no tracing */
michael@0:   err->num_warnings = 0;	/* no warnings emitted yet */
michael@0:   err->msg_code = 0;		/* may be useful as a flag for "no error" */
michael@0: 
michael@0:   /* Initialize message table pointers */
michael@0:   err->jpeg_message_table = jpeg_std_message_table;
michael@0:   err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;
michael@0: 
michael@0:   err->addon_message_table = NULL;
michael@0:   err->first_addon_message = 0;	/* for safety */
michael@0:   err->last_addon_message = 0;
michael@0: 
michael@0:   return err;
michael@0: }