compiler/libjpeg/main/jerror.c

   1 /*
   2     $Id$
   3 */
   4
   5 /*
   6  * jerror.c
   7  *
   8  * Copyright (C) 1991-1998, Thomas G. Lane.
   9  * This file is part of the Independent JPEG Group's software.
  10  * For conditions of distribution and use, see the accompanying README file.
  11  *
  12  * This file contains simple error-reporting and trace-message routines.
  13  * These are suitable for Unix-like systems and others where writing to
  14  * stderr is the right thing to do.  Many applications will want to replace
  15  * some or all of these routines.
  16  *
  17  * If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile,
  18  * you get a Windows-specific hack to display error messages in a dialog box.
  19  * It ain't much, but it beats dropping error messages into the bit bucket,
  20  * which is what happens to output to stderr under most Windows C compilers.
  21  *
  22  * These routines are used by both the compression and decompression code.
  23  */
  24
  25 /* this is not a core library module, so it doesn't define JPEG_INTERNALS */
  26 #include "jinclude.h"
  27 #include "jpeglib.h"
  28 #include "jversion.h"
  29 #include "jerror.h"
  30
  31 #ifdef USE_WINDOWS_MESSAGEBOX
  32 #include <windows.h>
  33 #endif
  34
  35 #ifndef EXIT_FAILURE            /* define exit() codes if not provided */
  36 #define EXIT_FAILURE  1
  37 #endif
  38
  39
  40 /*
  41  * Create the message string table.
  42  * We do this from the master message list in jerror.h by re-reading
  43  * jerror.h with a suitable definition for macro JMESSAGE.
  44  * The message table is made an external symbol just in case any applications
  45  * want to refer to it directly.
  46  */
  47
  48 #ifdef NEED_SHORT_EXTERNAL_NAMES
  49 #define jpeg_std_message_table  jMsgTable
  50 #endif
  51
  52 #define JMESSAGE(code,string)   string ,
  53
  54 const char * const jpeg_std_message_table[] = {
  55 #include "jerror.h"
  56   NULL
  57 };
  58
  59
  60 /*
  61  * Error exit handler: must not return to caller.
  62  *
  63  * Applications may override this if they want to get control back after
  64  * an error.  Typically one would longjmp somewhere instead of exiting.
  65  * The setjmp buffer can be made a private field within an expanded error
  66  * handler object.  Note that the info needed to generate an error message
  67  * is stored in the error object, so you can generate the message now or
  68  * later, at your convenience.
  69  * You should make sure that the JPEG object is cleaned up (with jpeg_abort
  70  * or jpeg_destroy) at some point.
  71  */
  72
  73 METHODDEF(void)
  74 error_exit (j_common_ptr cinfo)
  75 {
  76   /* Always display the message */
  77   (*cinfo->err->output_message) (cinfo);
  78
  79   /* Let the memory manager delete any temp files before we die */
  80   jpeg_destroy(cinfo);
  81
  82   exit(EXIT_FAILURE);
  83 }
  84
  85
  86 /*
  87  * Actual output of an error or trace message.
  88  * Applications may override this method to send JPEG messages somewhere
  89  * other than stderr.
  90  *
  91  * On Windows, printing to stderr is generally completely useless,
  92  * so we provide optional code to produce an error-dialog popup.
  93  * Most Windows applications will still prefer to override this routine,
  94  * but if they don't, it'll do something at least marginally useful.
  95  *
  96  * NOTE: to use the library in an environment that doesn't support the
  97  * C stdio library, you may have to delete the call to fprintf() entirely,
  98  * not just not use this routine.
  99  */
 100
 101 METHODDEF(void)
 102 output_message (j_common_ptr cinfo)
 103 {
 104   char buffer[JMSG_LENGTH_MAX];
 105
 106   /* Create the message */
 107   (*cinfo->err->format_message) (cinfo, buffer);
 108
 109 #ifdef USE_WINDOWS_MESSAGEBOX
 110   /* Display it in a message dialog box */
 111   MessageBox(GetActiveWindow(), buffer, "JPEG Library Error",
 112              MB_OK | MB_ICONERROR);
 113 #else
 114   /* Send it to stderr, adding a newline */
 115   fprintf(stderr, "%s\n", buffer);
 116 #endif
 117 }
 118
 119
 120 /*
 121  * Decide whether to emit a trace or warning message.
 122  * msg_level is one of:
 123  *   -1: recoverable corrupt-data warning, may want to abort.
 124  *    0: important advisory messages (always display to user).
 125  *    1: first level of tracing detail.
 126  *    2,3,...: successively more detailed tracing messages.
 127  * An application might override this method if it wanted to abort on warnings
 128  * or change the policy about which messages to display.
 129  */
 130
 131 METHODDEF(void)
 132 emit_message (j_common_ptr cinfo, int msg_level)
 133 {
 134   struct jpeg_error_mgr * err = cinfo->err;
 135
 136   if (msg_level < 0) {
 137     /* It's a warning message.  Since corrupt files may generate many warnings,
 138      * the policy implemented here is to show only the first warning,
 139      * unless trace_level >= 3.
 140      */
 141     if (err->num_warnings == 0 || err->trace_level >= 3)
 142       (*err->output_message) (cinfo);
 143     /* Always count warnings in num_warnings. */
 144     err->num_warnings++;
 145   } else {
 146     /* It's a trace message.  Show it if trace_level >= msg_level. */
 147     if (err->trace_level >= msg_level)
 148       (*err->output_message) (cinfo);
 149   }
 150 }
 151
 152
 153 /*
 154  * Format a message string for the most recent JPEG error or message.
 155  * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX
 156  * characters.  Note that no '\n' character is added to the string.
 157  * Few applications should need to override this method.
 158  */
 159
 160 METHODDEF(void)
 161 format_message (j_common_ptr cinfo, char * buffer)
 162 {
 163   struct jpeg_error_mgr * err = cinfo->err;
 164   int msg_code = err->msg_code;
 165   const char * msgtext = NULL;
 166   const char * msgptr;
 167   char ch;
 168   boolean isstring;
 169
 170   /* Look up message string in proper table */
 171   if (msg_code > 0 && msg_code <= err->last_jpeg_message) {
 172     msgtext = err->jpeg_message_table[msg_code];
 173   } else if (err->addon_message_table != NULL &&
 174              msg_code >= err->first_addon_message &&
 175              msg_code <= err->last_addon_message) {
 176     msgtext = err->addon_message_table[msg_code - err->first_addon_message];
 177   }
 178
 179   /* Defend against bogus message number */
 180   if (msgtext == NULL) {
 181     err->msg_parm.i[0] = msg_code;
 182     msgtext = err->jpeg_message_table[0];
 183   }
 184
 185   /* Check for string parameter, as indicated by %s in the message text */
 186   isstring = FALSE;
 187   msgptr = msgtext;
 188   while ((ch = *msgptr++) != '\0') {
 189     if (ch == '%') {
 190       if (*msgptr == 's') isstring = TRUE;
 191       break;
 192     }
 193   }
 194
 195   /* Format the message into the passed buffer */
 196   if (isstring)
 197     sprintf(buffer, msgtext, err->msg_parm.s);
 198   else
 199     sprintf(buffer, msgtext,
 200             err->msg_parm.i[0], err->msg_parm.i[1],
 201             err->msg_parm.i[2], err->msg_parm.i[3],
 202             err->msg_parm.i[4], err->msg_parm.i[5],
 203             err->msg_parm.i[6], err->msg_parm.i[7]);
 204 }
 205
 206
 207 /*
 208  * Reset error state variables at start of a new image.
 209  * This is called during compression startup to reset trace/error
 210  * processing to default state, without losing any application-specific
 211  * method pointers.  An application might possibly want to override
 212  * this method if it has additional error processing state.
 213  */
 214
 215 METHODDEF(void)
 216 reset_error_mgr (j_common_ptr cinfo)
 217 {
 218   cinfo->err->num_warnings = 0;
 219   /* trace_level is not reset since it is an application-supplied parameter */
 220   cinfo->err->msg_code = 0;     /* may be useful as a flag for "no error" */
 221 }
 222
 223
 224 /*
 225  * Fill in the standard error-handling methods in a jpeg_error_mgr object.
 226  * Typical call is:
 227  *      struct jpeg_compress_struct cinfo;
 228  *      struct jpeg_error_mgr err;
 229  *
 230  *      cinfo.err = jpeg_std_error(&err);
 231  * after which the application may override some of the methods.
 232  */
 233
 234 JGLOBAL(struct jpeg_error_mgr *)
 235 jpeg_std_error (struct jpeg_error_mgr * err)
 236 {
 237   err->error_exit = error_exit;
 238   err->emit_message = emit_message;
 239   err->output_message = output_message;
 240   err->format_message = format_message;
 241   err->reset_error_mgr = reset_error_mgr;
 242
 243   err->trace_level = 0;         /* default = no tracing */
 244   err->num_warnings = 0;        /* no warnings emitted yet */
 245   err->msg_code = 0;            /* may be useful as a flag for "no error" */
 246
 247   /* Initialize message table pointers */
 248   err->jpeg_message_table = jpeg_std_message_table;
 249   err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;
 250
 251   err->addon_message_table = NULL;
 252   err->first_addon_message = 0; /* for safety */
 253   err->last_addon_message = 0;
 254
 255   return err;
 256 }