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
8 * For conditions of distribution and use, see the accompanying README file.
10 * This file contains simple error-reporting and trace-message routines.
11 * These are suitable for Unix-like systems and others where writing to
12 * stderr is the right thing to do. Many applications will want to replace
13 * some or all of these routines.
15 * If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile,
16 * you get a Windows-specific hack to display error messages in a dialog box.
17 * It ain't much, but it beats dropping error messages into the bit bucket,
18 * which is what happens to output to stderr under most Windows C compilers.
20 * These routines are used by both the compression and decompression code.
23 /* this is not a core library module, so it doesn't define JPEG_INTERNALS */
29 #ifdef USE_WINDOWS_MESSAGEBOX
33 #ifndef EXIT_FAILURE /* define exit() codes if not provided */
34 #define EXIT_FAILURE 1
39 * Create the message string table.
40 * We do this from the master message list in jerror.h by re-reading
41 * jerror.h with a suitable definition for macro JMESSAGE.
42 * The message table is made an external symbol just in case any applications
43 * want to refer to it directly.
46 #define JMESSAGE(code,string) string ,
48 const char * const jpeg_std_message_table[] = {
55 * Error exit handler: must not return to caller.
57 * Applications may override this if they want to get control back after
58 * an error. Typically one would longjmp somewhere instead of exiting.
59 * The setjmp buffer can be made a private field within an expanded error
60 * handler object. Note that the info needed to generate an error message
61 * is stored in the error object, so you can generate the message now or
62 * later, at your convenience.
63 * You should make sure that the JPEG object is cleaned up (with jpeg_abort
64 * or jpeg_destroy) at some point.
68 error_exit (j_common_ptr cinfo)
70 /* Always display the message */
71 (*cinfo->err->output_message) (cinfo);
73 /* Let the memory manager delete any temp files before we die */
81 * Actual output of an error or trace message.
82 * Applications may override this method to send JPEG messages somewhere
85 * On Windows, printing to stderr is generally completely useless,
86 * so we provide optional code to produce an error-dialog popup.
87 * Most Windows applications will still prefer to override this routine,
88 * but if they don't, it'll do something at least marginally useful.
90 * NOTE: to use the library in an environment that doesn't support the
91 * C stdio library, you may have to delete the call to fprintf() entirely,
92 * not just not use this routine.
96 output_message (j_common_ptr cinfo)
98 char buffer[JMSG_LENGTH_MAX];
100 /* Create the message */
101 (*cinfo->err->format_message) (cinfo, buffer);
103 #ifdef USE_WINDOWS_MESSAGEBOX
104 /* Display it in a message dialog box */
105 MessageBox(GetActiveWindow(), buffer, "JPEG Library Error",
106 MB_OK | MB_ICONERROR);
108 /* Send it to stderr, adding a newline */
109 fprintf(stderr, "%s\n", buffer);
115 * Decide whether to emit a trace or warning message.
116 * msg_level is one of:
117 * -1: recoverable corrupt-data warning, may want to abort.
118 * 0: important advisory messages (always display to user).
119 * 1: first level of tracing detail.
120 * 2,3,...: successively more detailed tracing messages.
121 * An application might override this method if it wanted to abort on warnings
122 * or change the policy about which messages to display.
126 emit_message (j_common_ptr cinfo, int msg_level)
128 struct jpeg_error_mgr * err = cinfo->err;
131 /* It's a warning message. Since corrupt files may generate many warnings,
132 * the policy implemented here is to show only the first warning,
133 * unless trace_level >= 3.
135 if (err->num_warnings == 0 || err->trace_level >= 3)
136 (*err->output_message) (cinfo);
137 /* Always count warnings in num_warnings. */
140 /* It's a trace message. Show it if trace_level >= msg_level. */
141 if (err->trace_level >= msg_level)
142 (*err->output_message) (cinfo);
148 * Format a message string for the most recent JPEG error or message.
149 * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX
150 * characters. Note that no '\n' character is added to the string.
151 * Few applications should need to override this method.
155 format_message (j_common_ptr cinfo, char * buffer)
157 struct jpeg_error_mgr * err = cinfo->err;
158 int msg_code = err->msg_code;
159 const char * msgtext = NULL;
164 /* Look up message string in proper table */
165 if (msg_code > 0 && msg_code <= err->last_jpeg_message) {
166 msgtext = err->jpeg_message_table[msg_code];
167 } else if (err->addon_message_table != NULL &&
168 msg_code >= err->first_addon_message &&
169 msg_code <= err->last_addon_message) {
170 msgtext = err->addon_message_table[msg_code - err->first_addon_message];
173 /* Defend against bogus message number */
174 if (msgtext == NULL) {
175 err->msg_parm.i[0] = msg_code;
176 msgtext = err->jpeg_message_table[0];
179 /* Check for string parameter, as indicated by %s in the message text */
182 while ((ch = *msgptr++) != '\0') {
184 if (*msgptr == 's') isstring = TRUE;
189 /* Format the message into the passed buffer */
191 sprintf(buffer, msgtext, err->msg_parm.s);
193 sprintf(buffer, msgtext,
194 err->msg_parm.i[0], err->msg_parm.i[1],
195 err->msg_parm.i[2], err->msg_parm.i[3],
196 err->msg_parm.i[4], err->msg_parm.i[5],
197 err->msg_parm.i[6], err->msg_parm.i[7]);
202 * Reset error state variables at start of a new image.
203 * This is called during compression startup to reset trace/error
204 * processing to default state, without losing any application-specific
205 * method pointers. An application might possibly want to override
206 * this method if it has additional error processing state.
210 reset_error_mgr (j_common_ptr cinfo)
212 cinfo->err->num_warnings = 0;
213 /* trace_level is not reset since it is an application-supplied parameter */
214 cinfo->err->msg_code = 0; /* may be useful as a flag for "no error" */
219 * Fill in the standard error-handling methods in a jpeg_error_mgr object.
221 * struct jpeg_compress_struct cinfo;
222 * struct jpeg_error_mgr err;
224 * cinfo.err = jpeg_std_error(&err);
225 * after which the application may override some of the methods.
228 GLOBAL(struct jpeg_error_mgr *)
229 jpeg_std_error (struct jpeg_error_mgr * err)
231 err->error_exit = error_exit;
232 err->emit_message = emit_message;
233 err->output_message = output_message;
234 err->format_message = format_message;
235 err->reset_error_mgr = reset_error_mgr;
237 err->trace_level = 0; /* default = no tracing */
238 err->num_warnings = 0; /* no warnings emitted yet */
239 err->msg_code = 0; /* may be useful as a flag for "no error" */
241 /* Initialize message table pointers */
242 err->jpeg_message_table = jpeg_std_message_table;
243 err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;
245 err->addon_message_table = NULL;
246 err->first_addon_message = 0; /* for safety */
247 err->last_addon_message = 0;