1 /*
2 * jerror.c
3 *
4 * Copyright (C) 1991-1998, Thomas G. Lane.
5 * Modified 2012-2015 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 #ifdef USE_WINDOWS_MESSAGEBOX
23 #include <windows.h>
24 #endif
25
26 /* this is not a core library module, so it doesn't define JPEG_INTERNALS */
27 #include "jinclude.h"
28 #include "jpeglib.h"
29 #include "jversion.h"
30 #include "jerror.h"
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 }