jerror.cpp (6879B)
1 /* 2 * jerror.c 3 * 4 * Copyright (C) 1991-1994, Thomas G. Lane. 5 * This file is part of the Independent JPEG Group's software. 6 * For conditions of distribution and use, see the accompanying README file. 7 * 8 * This file contains simple error-reporting and trace-message routines. 9 * These are suitable for Unix-like systems and others where writing to 10 * stderr is the right thing to do. Many applications will want to replace 11 * some or all of these routines. 12 * 13 * These routines are used by both the compression and decompression code. 14 */ 15 16 /* this is not a core library module, so it doesn't define JPEG_INTERNALS */ 17 #include "jinclude.h" 18 #include "jpeglib.h" 19 #include "jversion.h" 20 #include "jerror.h" 21 22 #ifndef EXIT_FAILURE /* define exit() codes if not provided */ 23 #define EXIT_FAILURE 1 24 #endif 25 26 27 /* 28 * Create the message string table. 29 * We do this from the master message list in jerror.h by re-reading 30 * jerror.h with a suitable definition for macro JMESSAGE. 31 * The message table is made an external symbol just in case any applications 32 * want to refer to it directly. 33 */ 34 35 #ifdef NEED_SHORT_EXTERNAL_NAMES 36 #define jpeg_std_message_table jMsgTable 37 #endif 38 39 #define JMESSAGE(code,string) string , 40 41 const char * const jpeg_std_message_table[] = { 42 #include "jerror.h" 43 NULL 44 }; 45 46 47 /* 48 * Error exit handler: must not return to caller. 49 * 50 * Applications may override this if they want to get control back after 51 * an error. Typically one would longjmp somewhere instead of exiting. 52 * The setjmp buffer can be made a private field within an expanded error 53 * handler object. Note that the info needed to generate an error message 54 * is stored in the error object, so you can generate the message now or 55 * later, at your convenience. 56 * You should make sure that the JPEG object is cleaned up (with jpeg_abort 57 * or jpeg_destroy) at some point. 58 */ 59 60 METHODDEF void 61 error_exit (j_common_ptr cinfo) 62 { 63 char buffer[JMSG_LENGTH_MAX]; 64 65 /* Create the message */ 66 (*cinfo->err->format_message) (cinfo, buffer); 67 68 /* Let the memory manager delete any temp files before we die */ 69 jpeg_destroy(cinfo); 70 71 // FIXME: need to get this setup with an error handler 72 //Error("%s\n", buffer ); 73 } 74 75 76 /* 77 * Actual output of an error or trace message. 78 * Applications may override this method to send JPEG messages somewhere 79 * other than stderr. 80 */ 81 82 METHODDEF void 83 output_message (j_common_ptr cinfo) 84 { 85 char buffer[JMSG_LENGTH_MAX]; 86 87 /* Create the message */ 88 (*cinfo->err->format_message) (cinfo, buffer); 89 90 /* Send it to stderr, adding a newline */ 91 printf("%s\n", buffer); 92 } 93 94 95 /* 96 * Decide whether to emit a trace or warning message. 97 * msg_level is one of: 98 * -1: recoverable corrupt-data warning, may want to abort. 99 * 0: important advisory messages (always display to user). 100 * 1: first level of tracing detail. 101 * 2,3,...: successively more detailed tracing messages. 102 * An application might override this method if it wanted to abort on warnings 103 * or change the policy about which messages to display. 104 */ 105 106 METHODDEF void 107 emit_message (j_common_ptr cinfo, int msg_level) 108 { 109 struct jpeg_error_mgr * err = cinfo->err; 110 111 if (msg_level < 0) { 112 /* It's a warning message. Since corrupt files may generate many warnings, 113 * the policy implemented here is to show only the first warning, 114 * unless trace_level >= 3. 115 */ 116 if (err->num_warnings == 0 || err->trace_level >= 3) 117 (*err->output_message) (cinfo); 118 /* Always count warnings in num_warnings. */ 119 err->num_warnings++; 120 } else { 121 /* It's a trace message. Show it if trace_level >= msg_level. */ 122 if (err->trace_level >= msg_level) 123 (*err->output_message) (cinfo); 124 } 125 } 126 127 128 /* 129 * Format a message string for the most recent JPEG error or message. 130 * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX 131 * characters. Note that no '\n' character is added to the string. 132 * Few applications should need to override this method. 133 */ 134 135 METHODDEF void 136 format_message (j_common_ptr cinfo, char * buffer) 137 { 138 struct jpeg_error_mgr * err = cinfo->err; 139 int msg_code = err->msg_code; 140 const char * msgtext = NULL; 141 const char * msgptr; 142 char ch; 143 boolean isstring; 144 145 /* Look up message string in proper table */ 146 if (msg_code > 0 && msg_code <= err->last_jpeg_message) { 147 msgtext = err->jpeg_message_table[msg_code]; 148 } else if (err->addon_message_table != NULL && 149 msg_code >= err->first_addon_message && 150 msg_code <= err->last_addon_message) { 151 msgtext = err->addon_message_table[msg_code - err->first_addon_message]; 152 } 153 154 /* Defend against bogus message number */ 155 if (msgtext == NULL) { 156 err->msg_parm.i[0] = msg_code; 157 msgtext = err->jpeg_message_table[0]; 158 } 159 160 /* Check for string parameter, as indicated by %s in the message text */ 161 isstring = FALSE; 162 msgptr = msgtext; 163 while ((ch = *msgptr++) != '\0') { 164 if (ch == '%') { 165 if (*msgptr == 's') isstring = TRUE; 166 break; 167 } 168 } 169 170 /* Format the message into the passed buffer */ 171 if (isstring) 172 sprintf(buffer, msgtext, err->msg_parm.s); 173 else 174 sprintf(buffer, msgtext, 175 err->msg_parm.i[0], err->msg_parm.i[1], 176 err->msg_parm.i[2], err->msg_parm.i[3], 177 err->msg_parm.i[4], err->msg_parm.i[5], 178 err->msg_parm.i[6], err->msg_parm.i[7]); 179 } 180 181 182 /* 183 * Reset error state variables at start of a new image. 184 * This is called during compression startup to reset trace/error 185 * processing to default state, without losing any application-specific 186 * method pointers. An application might possibly want to override 187 * this method if it has additional error processing state. 188 */ 189 190 METHODDEF void 191 reset_error_mgr (j_common_ptr cinfo) 192 { 193 cinfo->err->num_warnings = 0; 194 /* trace_level is not reset since it is an application-supplied parameter */ 195 cinfo->err->msg_code = 0; /* may be useful as a flag for "no error" */ 196 } 197 198 199 /* 200 * Fill in the standard error-handling methods in a jpeg_error_mgr object. 201 * Typical call is: 202 * struct jpeg_compress_struct cinfo; 203 * struct jpeg_error_mgr err; 204 * 205 * cinfo.err = jpeg_std_error(&err); 206 * after which the application may override some of the methods. 207 */ 208 209 GLOBAL struct jpeg_error_mgr * 210 jpeg_std_error (struct jpeg_error_mgr * err) 211 { 212 err->error_exit = error_exit; 213 err->emit_message = emit_message; 214 err->output_message = output_message; 215 err->format_message = format_message; 216 err->reset_error_mgr = reset_error_mgr; 217 218 err->trace_level = 0; /* default = no tracing */ 219 err->num_warnings = 0; /* no warnings emitted yet */ 220 err->msg_code = 0; /* may be useful as a flag for "no error" */ 221 222 /* Initialize message table pointers */ 223 err->jpeg_message_table = jpeg_std_message_table; 224 err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1; 225 226 err->addon_message_table = NULL; 227 err->first_addon_message = 0; /* for safety */ 228 err->last_addon_message = 0; 229 230 return err; 231 }