1 /* 2 * jerror.c 3 * 4 * Copyright (C) 1991-1998, Thomas G. Lane. 5 * Modified 2012 by Guido Vollbeding. 6 * This file is part of the Independent JPEG Group's software. 7 * For conditions of distribution and use, see the accompanying README file. 8 * 9 * This file contains simple error-reporting and trace-message routines. 10 * These are suitable for Unix-like systems and others where writing to 11 * stderr is the right thing to do. Many applications will want to replace 12 * some or all of these routines. 13 * 14 * If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile, 15 * you get a Windows-specific hack to display error messages in a dialog box. 16 * It ain't much, but it beats dropping error messages into the bit bucket, 17 * which is what happens to output to stderr under most Windows C compilers. 18 * 19 * These routines are used by both the compression and decompression code. 20 */ 21 22 /* this is not a core library module, so it doesn't define JPEG_INTERNALS */ 23 #include "jinclude.h" 24 #include "jpeglib.h" 25 #include "jversion.h" 26 #include "jerror.h" 27 28 #ifdef USE_WINDOWS_MESSAGEBOX 29 #include <windows.h> 30 #endif 31 32 #ifndef EXIT_FAILURE /* define exit() codes if not provided */ 33 #define EXIT_FAILURE 1 34 #endif 35 36 37 /* 38 * Create the message string table. 39 * We do this from the master message list in jerror.h by re-reading 40 * jerror.h with a suitable definition for macro JMESSAGE. 41 * The message table is made an external symbol just in case any applications 42 * want to refer to it directly. 43 */ 44 45 #ifdef NEED_SHORT_EXTERNAL_NAMES 46 #define jpeg_std_message_table jMsgTable 47 #endif 48 49 #define JMESSAGE(code,string) string , 50 51 const char * const jpeg_std_message_table[] = { 52 #include "jerror.h" 53 NULL 54 }; 55 56 57 /* 58 * Error exit handler: must not return to caller. 59 * 60 * Applications may override this if they want to get control back after 61 * an error. Typically one would longjmp somewhere instead of exiting. 62 * The setjmp buffer can be made a private field within an expanded error 63 * handler object. Note that the info needed to generate an error message 64 * is stored in the error object, so you can generate the message now or 65 * later, at your convenience. 66 * You should make sure that the JPEG object is cleaned up (with jpeg_abort 67 * or jpeg_destroy) at some point. 68 */ 69 70 METHODDEF(noreturn_t) 71 error_exit (j_common_ptr cinfo) 72 { 73 /* Always display the message */ 74 (*cinfo->err->output_message) (cinfo); 75 76 /* Let the memory manager delete any temp files before we die */ 77 jpeg_destroy(cinfo); 78 79 exit(EXIT_FAILURE); 80 } 81 82 83 /* 84 * Actual output of an error or trace message. 85 * Applications may override this method to send JPEG messages somewhere 86 * other than stderr. 87 * 88 * On Windows, printing to stderr is generally completely useless, 89 * so we provide optional code to produce an error-dialog popup. 90 * Most Windows applications will still prefer to override this routine, 91 * but if they don't, it'll do something at least marginally useful. 92 * 93 * NOTE: to use the library in an environment that doesn't support the 94 * C stdio library, you may have to delete the call to fprintf() entirely, 95 * not just not use this routine. 96 */ 97 98 METHODDEF(void) 99 output_message (j_common_ptr cinfo) 100 { 101 char buffer[JMSG_LENGTH_MAX]; 102 103 /* Create the message */ 104 (*cinfo->err->format_message) (cinfo, buffer); 105 106 #ifdef USE_WINDOWS_MESSAGEBOX 107 /* Display it in a message dialog box */ 108 MessageBox(GetActiveWindow(), buffer, "JPEG Library Error", 109 MB_OK | MB_ICONERROR); 110 #else 111 /* Send it to stderr, adding a newline */ 112 fprintf(stderr, "%s\n", buffer); 113 #endif 114 } 115 116 117 /* 118 * Decide whether to emit a trace or warning message. 119 * msg_level is one of: 120 * -1: recoverable corrupt-data warning, may want to abort. 121 * 0: important advisory messages (always display to user). 122 * 1: first level of tracing detail. 123 * 2,3,...: successively more detailed tracing messages. 124 * An application might override this method if it wanted to abort on warnings 125 * or change the policy about which messages to display. 126 */ 127 128 METHODDEF(void) 129 emit_message (j_common_ptr cinfo, int msg_level) 130 { 131 struct jpeg_error_mgr * err = cinfo->err; 132 133 if (msg_level < 0) { 134 /* It's a warning message. Since corrupt files may generate many warnings, 135 * the policy implemented here is to show only the first warning, 136 * unless trace_level >= 3. 137 */ 138 if (err->num_warnings == 0 || err->trace_level >= 3) 139 (*err->output_message) (cinfo); 140 /* Always count warnings in num_warnings. */ 141 err->num_warnings++; 142 } else { 143 /* It's a trace message. Show it if trace_level >= msg_level. */ 144 if (err->trace_level >= msg_level) 145 (*err->output_message) (cinfo); 146 } 147 } 148 149 150 /* 151 * Format a message string for the most recent JPEG error or message. 152 * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX 153 * characters. Note that no '\n' character is added to the string. 154 * Few applications should need to override this method. 155 */ 156 157 METHODDEF(void) 158 format_message (j_common_ptr cinfo, char * buffer) 159 { 160 struct jpeg_error_mgr * err = cinfo->err; 161 int msg_code = err->msg_code; 162 const char * msgtext = NULL; 163 const char * msgptr; 164 char ch; 165 boolean isstring; 166 167 /* Look up message string in proper table */ 168 if (msg_code > 0 && msg_code <= err->last_jpeg_message) { 169 msgtext = err->jpeg_message_table[msg_code]; 170 } else if (err->addon_message_table != NULL && 171 msg_code >= err->first_addon_message && 172 msg_code <= err->last_addon_message) { 173 msgtext = err->addon_message_table[msg_code - err->first_addon_message]; 174 } 175 176 /* Defend against bogus message number */ 177 if (msgtext == NULL) { 178 err->msg_parm.i[0] = msg_code; 179 msgtext = err->jpeg_message_table[0]; 180 } 181 182 /* Check for string parameter, as indicated by %s in the message text */ 183 isstring = FALSE; 184 msgptr = msgtext; 185 while ((ch = *msgptr++) != '\0') { 186 if (ch == '%') { 187 if (*msgptr == 's') isstring = TRUE; 188 break; 189 } 190 } 191 192 /* Format the message into the passed buffer */ 193 if (isstring) 194 sprintf(buffer, msgtext, err->msg_parm.s); 195 else 196 sprintf(buffer, msgtext, 197 err->msg_parm.i[0], err->msg_parm.i[1], 198 err->msg_parm.i[2], err->msg_parm.i[3], 199 err->msg_parm.i[4], err->msg_parm.i[5], 200 err->msg_parm.i[6], err->msg_parm.i[7]); 201 } 202 203 204 /* 205 * Reset error state variables at start of a new image. 206 * This is called during compression startup to reset trace/error 207 * processing to default state, without losing any application-specific 208 * method pointers. An application might possibly want to override 209 * this method if it has additional error processing state. 210 */ 211 212 METHODDEF(void) 213 reset_error_mgr (j_common_ptr cinfo) 214 { 215 cinfo->err->num_warnings = 0; 216 /* trace_level is not reset since it is an application-supplied parameter */ 217 cinfo->err->msg_code = 0; /* may be useful as a flag for "no error" */ 218 } 219 220 221 /* 222 * Fill in the standard error-handling methods in a jpeg_error_mgr object. 223 * Typical call is: 224 * struct jpeg_compress_struct cinfo; 225 * struct jpeg_error_mgr err; 226 * 227 * cinfo.err = jpeg_std_error(&err); 228 * after which the application may override some of the methods. 229 */ 230 231 GLOBAL(struct jpeg_error_mgr *) 232 jpeg_std_error (struct jpeg_error_mgr * err) 233 { 234 err->error_exit = error_exit; 235 err->emit_message = emit_message; 236 err->output_message = output_message; 237 err->format_message = format_message; 238 err->reset_error_mgr = reset_error_mgr; 239 240 err->trace_level = 0; /* default = no tracing */ 241 err->num_warnings = 0; /* no warnings emitted yet */ 242 err->msg_code = 0; /* may be useful as a flag for "no error" */ 243 244 /* Initialize message table pointers */ 245 err->jpeg_message_table = jpeg_std_message_table; 246 err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1; 247 248 err->addon_message_table = NULL; 249 err->first_addon_message = 0; /* for safety */ 250 err->last_addon_message = 0; 251 252 return err; 253 } 254
