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