1/* 2 * reserved comment block 3 * DO NOT REMOVE OR ALTER! 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 54const 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 73METHODDEF(void) 74error_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 /* 83 * This should never happen since the Java library replaces the 84 * error_exit pointer in the error handler structs it uses. 85 * 86 * exit(EXIT_FAILURE); 87 */ 88} 89 90 91/* 92 * Actual output of an error or trace message. 93 * Applications may override this method to send JPEG messages somewhere 94 * other than stderr. 95 * 96 * On Windows, printing to stderr is generally completely useless, 97 * so we provide optional code to produce an error-dialog popup. 98 * Most Windows applications will still prefer to override this routine, 99 * but if they don't, it'll do something at least marginally useful. 100 * 101 * NOTE: to use the library in an environment that doesn't support the 102 * C stdio library, you may have to delete the call to fprintf() entirely, 103 * not just not use this routine. 104 */ 105 106METHODDEF(void) 107output_message (j_common_ptr cinfo) 108{ 109 char buffer[JMSG_LENGTH_MAX]; 110 111 /* Create the message */ 112 (*cinfo->err->format_message) (cinfo, buffer); 113 114#ifdef USE_WINDOWS_MESSAGEBOX 115 /* Display it in a message dialog box */ 116 MessageBox(GetActiveWindow(), buffer, "JPEG Library Error", 117 MB_OK | MB_ICONERROR); 118#else 119 /* Send it to stderr, adding a newline */ 120 fprintf(stderr, "%s\n", buffer); 121#endif 122} 123 124 125/* 126 * Decide whether to emit a trace or warning message. 127 * msg_level is one of: 128 * -1: recoverable corrupt-data warning, may want to abort. 129 * 0: important advisory messages (always display to user). 130 * 1: first level of tracing detail. 131 * 2,3,...: successively more detailed tracing messages. 132 * An application might override this method if it wanted to abort on warnings 133 * or change the policy about which messages to display. 134 */ 135 136METHODDEF(void) 137emit_message (j_common_ptr cinfo, int msg_level) 138{ 139 struct jpeg_error_mgr * err = cinfo->err; 140 141 if (msg_level < 0) { 142 /* It's a warning message. Since corrupt files may generate many warnings, 143 * the policy implemented here is to show only the first warning, 144 * unless trace_level >= 3. 145 */ 146 if (err->num_warnings == 0 || err->trace_level >= 3) 147 (*err->output_message) (cinfo); 148 /* Always count warnings in num_warnings. */ 149 err->num_warnings++; 150 } else { 151 /* It's a trace message. Show it if trace_level >= msg_level. */ 152 if (err->trace_level >= msg_level) 153 (*err->output_message) (cinfo); 154 } 155} 156 157 158/* 159 * Format a message string for the most recent JPEG error or message. 160 * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX 161 * characters. Note that no '\n' character is added to the string. 162 * Few applications should need to override this method. 163 */ 164 165METHODDEF(void) 166format_message (j_common_ptr cinfo, char * buffer) 167{ 168 169/* Had to kill this function altogether 170 to avoid linking to VM when building the splash screen with static libjpeg */ 171 172#ifndef SPLASHSCREEN 173 int jio_snprintf(char *str, size_t count, const char *fmt, ...); 174 struct jpeg_error_mgr * err = cinfo->err; 175 int msg_code = err->msg_code; 176 const char * msgtext = NULL; 177 const char * msgptr; 178 char ch; 179 boolean isstring; 180 181 /* Look up message string in proper table */ 182 if (msg_code > 0 && msg_code <= err->last_jpeg_message) { 183 msgtext = err->jpeg_message_table[msg_code]; 184 } else if (err->addon_message_table != NULL && 185 msg_code >= err->first_addon_message && 186 msg_code <= err->last_addon_message) { 187 msgtext = err->addon_message_table[msg_code - err->first_addon_message]; 188 } 189 190 /* Defend against bogus message number */ 191 if (msgtext == NULL) { 192 err->msg_parm.i[0] = msg_code; 193 msgtext = err->jpeg_message_table[0]; 194 } 195 196 /* Check for string parameter, as indicated by %s in the message text */ 197 isstring = FALSE; 198 msgptr = msgtext; 199 while ((ch = *msgptr++) != '\0') { 200 if (ch == '%') { 201 if (*msgptr == 's') isstring = TRUE; 202 break; 203 } 204 } 205 206 /* Format the message into the passed buffer */ 207 if (isstring) 208 /* Buffer size is JMSG_LENGTH_MAX, quietly truncate on overflow */ 209 (void) jio_snprintf(buffer, JMSG_LENGTH_MAX, msgtext, err->msg_parm.s); 210 else 211 /* Buffer size is JMSG_LENGTH_MAX, quietly truncate on overflow */ 212 (void) jio_snprintf(buffer, JMSG_LENGTH_MAX, msgtext, 213 err->msg_parm.i[0], err->msg_parm.i[1], 214 err->msg_parm.i[2], err->msg_parm.i[3], 215 err->msg_parm.i[4], err->msg_parm.i[5], 216 err->msg_parm.i[6], err->msg_parm.i[7]); 217#else /* SPLASHSCREEN */ 218 *buffer = '\0'; 219#endif /* SPLASHSCREEN */ 220} 221 222 223/* 224 * Reset error state variables at start of a new image. 225 * This is called during compression startup to reset trace/error 226 * processing to default state, without losing any application-specific 227 * method pointers. An application might possibly want to override 228 * this method if it has additional error processing state. 229 */ 230 231METHODDEF(void) 232reset_error_mgr (j_common_ptr cinfo) 233{ 234 cinfo->err->num_warnings = 0; 235 /* trace_level is not reset since it is an application-supplied parameter */ 236 cinfo->err->msg_code = 0; /* may be useful as a flag for "no error" */ 237} 238 239 240/* 241 * Fill in the standard error-handling methods in a jpeg_error_mgr object. 242 * Typical call is: 243 * struct jpeg_compress_struct cinfo; 244 * struct jpeg_error_mgr err; 245 * 246 * cinfo.err = jpeg_std_error(&err); 247 * after which the application may override some of the methods. 248 */ 249 250GLOBAL(struct jpeg_error_mgr *) 251jpeg_std_error (struct jpeg_error_mgr * err) 252{ 253 err->error_exit = error_exit; 254 err->emit_message = emit_message; 255 err->output_message = output_message; 256 err->format_message = format_message; 257 err->reset_error_mgr = reset_error_mgr; 258 259 err->trace_level = 0; /* default = no tracing */ 260 err->num_warnings = 0; /* no warnings emitted yet */ 261 err->msg_code = 0; /* may be useful as a flag for "no error" */ 262 263 /* Initialize message table pointers */ 264 err->jpeg_message_table = jpeg_std_message_table; 265 err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1; 266 267 err->addon_message_table = NULL; 268 err->first_addon_message = 0; /* for safety */ 269 err->last_addon_message = 0; 270 271 return err; 272} 273