This module provides the C level error handling functionality for
Imager.
-A few functions return or pass in a char **, this is a NULL terminated
-list of pointers to error messages (which are NUL terminated strings,
-just as it normal in C :). Even though these aren't passed as char
-const * const * pointers, don't modify the strings or the pointers.
+A few functions return or pass in an i_errmsg *, this is list of error
+structures, terminated by an entry with a NULL msg value, each of
+which contains a msg and an error code. Even though these aren't
+passed as i_errmsg const * pointers, don't modify the strings
+or the pointers.
The interface as currently defined isn't thread safe, unfortunately.
/* we never actually use the last item - it's the NULL terminator */
#define ERRSTK 20
-char *error_stack[ERRSTK];
-int error_sp = ERRSTK - 1;
+static i_errmsg error_stack[ERRSTK];
+static int error_sp = ERRSTK - 1;
/* we track the amount of space used each string, so we don't reallocate
space unless we need to.
This also means that a memory tracking library may see the memory
allocated for this as a leak. */
-int error_space[ERRSTK];
+static int error_space[ERRSTK];
static i_error_cb error_cb;
static i_failed_cb failed_cb;
when your program starts.
*/
void i_set_argv0(char const *name) {
+ char *dupl;
if (!name)
return;
- char *dupl = mymalloc(strlen(name)+1);
+ dupl = mymalloc(strlen(name)+1);
strcpy(dupl, name);
if (argv0)
myfree(argv0);
=cut
*/
-char **i_errors() {
+i_errmsg *i_errors() {
return error_stack + error_sp;
}
=cut */
void i_clear_error() {
+#ifdef IMAGER_DEBUG_MALLOC
+ int i;
+
+ for (i = 0; i < ERRSTK; ++i) {
+ if (error_space[i]) {
+ myfree(error_stack[i].msg);
+ error_stack[i].msg = NULL;
+ error_space[i] = 0;
+ }
+ }
+#endif
error_sp = ERRSTK-1;
}
/*
-=item i_push_error(char const *msg)
+=item i_push_error(int code, char const *msg)
Called by an imager function to push an error message onto the stack.
=cut
*/
-void i_push_error(char const *msg) {
+void i_push_error(int code, char const *msg) {
int size = strlen(msg)+1;
if (error_sp <= 0)
--error_sp;
if (error_space[error_sp] < size) {
- if (error_stack[error_sp])
- myfree(error_stack[error_sp]);
+ if (error_stack[error_sp].msg)
+ myfree(error_stack[error_sp].msg);
/* memory allocated on the following line is only ever release when
we need a bigger string */
- error_stack[error_sp] = mymalloc(size);
+ error_stack[error_sp].msg = mymalloc(size);
error_space[error_sp] = size;
}
- strcpy(error_stack[error_sp], msg);
+ strcpy(error_stack[error_sp].msg, msg);
+ error_stack[error_sp].code = code;
if (error_cb)
- error_cb(msg);
+ error_cb(code, msg);
+}
+
+/*
+=item i_push_errorvf(int code, char const *fmt, va_list ap)
+
+Intended for use by higher level functions, takes a varargs pointer
+and a format to produce the finally pushed error message.
+
+=cut
+*/
+void i_push_errorvf(int code, char const *fmt, va_list ap) {
+ char buf[1024];
+#if defined(_MSC_VER)
+ _vsnprintf(buf, sizeof(buf), fmt, ap);
+#else
+ /* is there a way to detect vsnprintf()?
+ for this and other functions we need some mechanism to handle
+ detection (like perl's Configure, or autoconf)
+ */
+ vsprintf(buf, fmt, ap);
+#endif
+ i_push_error(code, buf);
+}
+
+/*
+=item i_push_errorf(int code, char const *fmt, ...)
+
+A version of i_push_error() that does printf() like formating.
+
+=cut
+*/
+void i_push_errorf(int code, char const *fmt, ...) {
+ va_list ap;
+ va_start(ap, fmt);
+ i_push_errorvf(code, fmt, ap);
+ va_end(ap);
}
/*
Called by Imager code to indicate that a top-level has failed.
-msg can be NULL.
+msg can be NULL, in which case no error is pushed.
Calls the current failed callback, if any.
=cut
*/
-int i_failed(char const *msg) {
+int i_failed(int code, char const *msg) {
if (msg)
- i_push_error(msg);
+ i_push_error(code, msg);
if (failed_cb)
failed_cb(error_stack + error_sp);
if (failures_fatal) {
+ int sp;
+ int total; /* total length of error messages */
+ char *full; /* full message for logging */
if (argv0)
fprintf(stderr, "%s: ", argv0);
fputs("error:\n", stderr);
- while (error_stack[error_sp]) {
- fprintf(stderr, " %s\n", error_stack[error_sp]);
- ++error_sp;
+ sp = error_sp;
+ while (error_stack[sp].msg) {
+ fprintf(stderr, " %s\n", error_stack[sp].msg);
+ ++sp;
+ }
+ /* we want to log the error too, build an error message to hand to
+ m_fatal() */
+ total = 1; /* remember the NUL */
+ for (sp = error_sp; error_stack[sp].msg; ++sp) {
+ total += strlen(error_stack[sp].msg) + 2;
+ }
+ full = mymalloc(total);
+ if (!full) {
+ /* just quit, at least it's on stderr */
+ exit(EXIT_FAILURE);
+ }
+ *full = 0;
+ for (sp = error_sp; error_stack[sp].msg; ++sp) {
+ strcat(full, error_stack[sp].msg);
+ strcat(full, ": ");
}
- exit(EXIT_FAILURE);
+ /* lose the extra ": " */
+ full[strlen(full)-2] = '\0';
+ m_fatal(EXIT_FAILURE, "%s", full);
}
return 0;