Blame |
Last modification |
View Log
| RSS feed
/*
* jerror.c
*
* Copyright (C) 1991-1998, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains simple error-reporting and trace-message routines.
* These are suitable for Unix-like systems and others where writing to
* stderr is the right thing to do. Many applications will want to replace
* some or all of these routines.
*
* If you define USE_WINDOWS_MESSAGEBOX in jconfig.h or in the makefile,
* you get a Windows-specific hack to display error messages in a dialog box.
* It ain't much, but it beats dropping error messages into the bit bucket,
* which is what happens to output to stderr under most Windows C compilers.
*
* These routines are used by both the compression and decompression code.
*/
/* this is not a core library module, so it doesn't define JPEG_INTERNALS */
#include "jinclude.h"
#include "jpeglib.h"
#include "jversion.h"
#include "jerror.h"
#ifdef USE_WINDOWS_MESSAGEBOX
#include <windows.h>
#endif
#ifndef EXIT_FAILURE /* define exit() codes if not provided */
#define EXIT_FAILURE 1
#endif
/*
* Create the message string table.
* We do this from the master message list in jerror.h by re-reading
* jerror.h with a suitable definition for macro JMESSAGE.
* The message table is made an external symbol just in case any applications
* want to refer to it directly.
*/
#ifdef NEED_SHORT_EXTERNAL_NAMES
#define jpeg_std_message_table jMsgTable
#endif
#define JMESSAGE(code,string) string ,
const char * const jpeg_std_message_table
[] = {
#include "jerror.h"
NULL
};
/*
* Error exit handler: must not return to caller.
*
* Applications may override this if they want to get control back after
* an error. Typically one would longjmp somewhere instead of exiting.
* The setjmp buffer can be made a private field within an expanded error
* handler object. Note that the info needed to generate an error message
* is stored in the error object, so you can generate the message now or
* later, at your convenience.
* You should make sure that the JPEG object is cleaned up (with jpeg_abort
* or jpeg_destroy) at some point.
*/
METHODDEF
(void)
error_exit
(j_common_ptr cinfo
)
{
/* Always display the message */
(*cinfo
->err
->output_message
) (cinfo
);
/* Let the memory manager delete any temp files before we die */
jpeg_destroy
(cinfo
);
exit(EXIT_FAILURE
);
}
/*
* Actual output of an error or trace message.
* Applications may override this method to send JPEG messages somewhere
* other than stderr.
*
* On Windows, printing to stderr is generally completely useless,
* so we provide optional code to produce an error-dialog popup.
* Most Windows applications will still prefer to override this routine,
* but if they don't, it'll do something at least marginally useful.
*
* NOTE: to use the library in an environment that doesn't support the
* C stdio library, you may have to delete the call to fprintf() entirely,
* not just not use this routine.
*/
METHODDEF
(void)
output_message
(j_common_ptr cinfo
)
{
char buffer
[JMSG_LENGTH_MAX
];
/* Create the message */
(*cinfo
->err
->format_message
) (cinfo
, buffer
);
#ifdef USE_WINDOWS_MESSAGEBOX
/* Display it in a message dialog box */
MessageBox
(GetActiveWindow
(), buffer
, "JPEG Library Error",
MB_OK
| MB_ICONERROR
);
#else
/* Send it to stderr, adding a newline */
fprintf(stderr
, "%s\n", buffer
);
#endif
}
/*
* Decide whether to emit a trace or warning message.
* msg_level is one of:
* -1: recoverable corrupt-data warning, may want to abort.
* 0: important advisory messages (always display to user).
* 1: first level of tracing detail.
* 2,3,...: successively more detailed tracing messages.
* An application might override this method if it wanted to abort on warnings
* or change the policy about which messages to display.
*/
METHODDEF
(void)
emit_message
(j_common_ptr cinfo
, int msg_level
)
{
struct jpeg_error_mgr
* err
= cinfo
->err
;
if (msg_level
< 0) {
/* It's a warning message. Since corrupt files may generate many warnings,
* the policy implemented here is to show only the first warning,
* unless trace_level >= 3.
*/
if (err
->num_warnings
== 0 || err
->trace_level
>= 3)
(*err
->output_message
) (cinfo
);
/* Always count warnings in num_warnings. */
err
->num_warnings
++;
} else {
/* It's a trace message. Show it if trace_level >= msg_level. */
if (err
->trace_level
>= msg_level
)
(*err
->output_message
) (cinfo
);
}
}
/*
* Format a message string for the most recent JPEG error or message.
* The message is stored into buffer, which should be at least JMSG_LENGTH_MAX
* characters. Note that no '\n' character is added to the string.
* Few applications should need to override this method.
*/
METHODDEF
(void)
format_message
(j_common_ptr cinfo
, char * buffer
)
{
struct jpeg_error_mgr
* err
= cinfo
->err
;
int msg_code
= err
->msg_code
;
const char * msgtext
= NULL
;
const char * msgptr
;
char ch
;
boolean isstring
;
/* Look up message string in proper table */
if (msg_code
> 0 && msg_code
<= err
->last_jpeg_message
) {
msgtext
= err
->jpeg_message_table
[msg_code
];
} else if (err
->addon_message_table
!= NULL
&&
msg_code
>= err
->first_addon_message
&&
msg_code
<= err
->last_addon_message
) {
msgtext
= err
->addon_message_table
[msg_code
- err
->first_addon_message
];
}
/* Defend against bogus message number */
if (msgtext
== NULL
) {
err
->msg_parm.
i[0] = msg_code
;
msgtext
= err
->jpeg_message_table
[0];
}
/* Check for string parameter, as indicated by %s in the message text */
isstring
= FALSE
;
msgptr
= msgtext
;
while ((ch
= *msgptr
++) != '\0') {
if (ch
== '%') {
if (*msgptr
== 's') isstring
= TRUE
;
break;
}
}
/* Format the message into the passed buffer */
if (isstring
)
sprintf(buffer
, msgtext
, err
->msg_parm.
s);
else
sprintf(buffer
, msgtext
,
err
->msg_parm.
i[0], err
->msg_parm.
i[1],
err
->msg_parm.
i[2], err
->msg_parm.
i[3],
err
->msg_parm.
i[4], err
->msg_parm.
i[5],
err
->msg_parm.
i[6], err
->msg_parm.
i[7]);
}
/*
* Reset error state variables at start of a new image.
* This is called during compression startup to reset trace/error
* processing to default state, without losing any application-specific
* method pointers. An application might possibly want to override
* this method if it has additional error processing state.
*/
METHODDEF
(void)
reset_error_mgr
(j_common_ptr cinfo
)
{
cinfo
->err
->num_warnings
= 0;
/* trace_level is not reset since it is an application-supplied parameter */
cinfo
->err
->msg_code
= 0; /* may be useful as a flag for "no error" */
}
/*
* Fill in the standard error-handling methods in a jpeg_error_mgr object.
* Typical call is:
* struct jpeg_compress_struct cinfo;
* struct jpeg_error_mgr err;
*
* cinfo.err = jpeg_std_error(&err);
* after which the application may override some of the methods.
*/
GLOBAL
(struct jpeg_error_mgr
*)
jpeg_std_error
(struct jpeg_error_mgr
* err
)
{
err
->error_exit
= error_exit
;
err
->emit_message
= emit_message
;
err
->output_message
= output_message
;
err
->format_message
= format_message
;
err
->reset_error_mgr
= reset_error_mgr
;
err
->trace_level
= 0; /* default = no tracing */
err
->num_warnings
= 0; /* no warnings emitted yet */
err
->msg_code
= 0; /* may be useful as a flag for "no error" */
/* Initialize message table pointers */
err
->jpeg_message_table
= jpeg_std_message_table
;
err
->last_jpeg_message
= (int) JMSG_LASTMSGCODE
- 1;
err
->addon_message_table
= NULL
;
err
->first_addon_message
= 0; /* for safety */
err
->last_addon_message
= 0;
return err
;
}