1 /*
2 * jerror.c
3 *
4 * Copyright (C) 1991-1998, 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 * If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile,
14 * you get a Windows-specific hack to display error messages in a dialog box.
15 * It ain't much, but it beats dropping error messages into the bit bucket,
16 * which is what happens to output to stderr under most Windows C compilers.
17 *
18 * These routines are used by both the compression and decompression code.
19 */
20 
21 /* this is not a core library module, so it doesn't define JPEG_INTERNALS */
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include "jinclude.h"
25 #include "jpeglib.h"
26 #include "jversion.h"
27 #include "jerror.h"
28 
29 #ifdef USE_WINDOWS_MESSAGEBOX
30 #include <windows.h>
31 #endif
32 
33 #ifndef EXIT_FAILURE		/* define exit() codes if not provided */
34 #define EXIT_FAILURE  1
35 #endif
36 
37 
38 /*
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.
44 */
45 
46 #define JMESSAGE(code,string)	string ,
47 
48 const char * const jpeg_std_message_table[] = {
49 #include "jerror.h"
50 	NULL
51 };
52 
53 
54 /*
55 * Error exit handler: must not return to caller.
56 *
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.
65 */
66 
67 METHODDEF(void)
error_exit(j_common_ptr cinfo)68 error_exit (j_common_ptr cinfo)
69 {
70 	/* Always display the message */
71 	(*cinfo->err->output_message) (cinfo);
72 
73 	/* Let the memory manager delete any temp files before we die */
74 	jpeg_destroy(cinfo);
75 
76 	exit(EXIT_FAILURE);
77 }
78 
79 
80 /*
81 * Actual output of an error or trace message.
82 * Applications may override this method to send JPEG messages somewhere
83 * other than stderr.
84 *
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.
89 *
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.
93 */
94 
95 METHODDEF(void)
output_message(j_common_ptr cinfo)96 output_message (j_common_ptr cinfo)
97 {
98 	char buffer[JMSG_LENGTH_MAX];
99 
100 	/* Create the message */
101 	(*cinfo->err->format_message) (cinfo, buffer);
102 
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);
107 #else
108 	/* Send it to stderr, adding a newline */
109 	fprintf(stderr, "%s\n", buffer);
110 #endif
111 }
112 
113 
114 /*
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.
123 */
124 
125 METHODDEF(void)
emit_message(j_common_ptr cinfo,int msg_level)126 emit_message (j_common_ptr cinfo, int msg_level)
127 {
128 	struct jpeg_error_mgr * err = cinfo->err;
129 
130 	if (msg_level < 0) {
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.
134 		*/
135 		if (err->num_warnings == 0 || err->trace_level >= 3)
136 			(*err->output_message) (cinfo);
137 		/* Always count warnings in num_warnings. */
138 		err->num_warnings++;
139 	} else {
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);
143 	}
144 }
145 
146 
147 /*
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.
152 */
153 
154 METHODDEF(void)
format_message(j_common_ptr cinfo,char * buffer)155 format_message (j_common_ptr cinfo, char * buffer)
156 {
157 	struct jpeg_error_mgr * err = cinfo->err;
158 	int msg_code = err->msg_code;
159 	const char * msgtext = NULL;
160 	const char * msgptr;
161 	char ch;
162 	boolean isstring;
163 
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];
171 	}
172 
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];
177 	}
178 
179 	/* Check for string parameter, as indicated by %s in the message text */
180 	isstring = FALSE;
181 	msgptr = msgtext;
182 	while ((ch = *msgptr++) != '\0') {
183 		if (ch == '%') {
184 			if (*msgptr == 's') isstring = TRUE;
185 			break;
186 		}
187 	}
188 
189 	/* Format the message into the passed buffer */
190 #if _MSC_VER >= 1400
191 	if (isstring)
192 		sprintf_s(buffer, JMSG_LENGTH_MAX, msgtext, err->msg_parm.s);
193 	else
194 		sprintf_s(buffer, JMSG_LENGTH_MAX, 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 #else
200 	if (isstring)
201 		sprintf(buffer, msgtext, err->msg_parm.s);
202 	else
203 		sprintf(buffer, msgtext,
204 		err->msg_parm.i[0], err->msg_parm.i[1],
205 		err->msg_parm.i[2], err->msg_parm.i[3],
206 		err->msg_parm.i[4], err->msg_parm.i[5],
207 		err->msg_parm.i[6], err->msg_parm.i[7]);
208 #endif
209 }
210 
211 
212 /*
213 * Reset error state variables at start of a new image.
214 * This is called during compression startup to reset trace/error
215 * processing to default state, without losing any application-specific
216 * method pointers.  An application might possibly want to override
217 * this method if it has additional error processing state.
218 */
219 
220 METHODDEF(void)
reset_error_mgr(j_common_ptr cinfo)221 reset_error_mgr (j_common_ptr cinfo)
222 {
223 	cinfo->err->num_warnings = 0;
224 	/* trace_level is not reset since it is an application-supplied parameter */
225 	cinfo->err->msg_code = 0;	/* may be useful as a flag for "no error" */
226 }
227 
228 
229 /*
230 * Fill in the standard error-handling methods in a jpeg_error_mgr object.
231 * Typical call is:
232 *	struct jpeg_compress_struct cinfo;
233 *	struct jpeg_error_mgr err;
234 *
235 *	cinfo.err = jpeg_std_error(&err);
236 * after which the application may override some of the methods.
237 */
238 
239 GLOBAL(struct jpeg_error_mgr *)
jpeg_std_error(struct jpeg_error_mgr * err)240 jpeg_std_error (struct jpeg_error_mgr * err)
241 {
242 	err->error_exit = error_exit;
243 	err->emit_message = emit_message;
244 	err->output_message = output_message;
245 	err->format_message = format_message;
246 	err->reset_error_mgr = reset_error_mgr;
247 
248 	err->trace_level = 0;		/* default = no tracing */
249 	err->num_warnings = 0;	/* no warnings emitted yet */
250 	err->msg_code = 0;		/* may be useful as a flag for "no error" */
251 
252 	/* Initialize message table pointers */
253 	err->jpeg_message_table = jpeg_std_message_table;
254 	err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;
255 
256 	err->addon_message_table = NULL;
257 	err->first_addon_message = 0;	/* for safety */
258 	err->last_addon_message = 0;
259 
260 	return err;
261 }
262