-
-/*
- * error.c -- main error handling routines
+/* error.c -- main error handling routines
*
- * $Id$
+ * This code is Copyright (c) 2002, by the authors of nmh. See the
+ * COPYRIGHT file in the root directory of the nmh distribution for
+ * complete copyright information.
*/
#include <h/mh.h>
-#ifdef HAVE_WRITEV
-# include <sys/types.h>
-# include <sys/uio.h>
-#endif
+#include <sys/types.h>
+#include <sys/uio.h>
-extern int errno;
+/* inform calls advertise() with no what and no tail.
+ * Thus the simple "[invo_name: ]fmt\n" results. */
+void inform(char *fmt, ...)
+{
+ va_list ap;
-/*
- * print out error message
- */
+ va_start(ap, fmt);
+ advertise(NULL, NULL, fmt, ap);
+ va_end(ap);
+}
+
+
+/* advise calls advertise() with no tail to print fmt, and perhaps what,
+ * to stderr.
+ * Thus "[invo_name: ]fmt[[ what]: errno]\n" results. */
void
-advise (char *what, char *fmt, ...)
+advise (const char *what, const char *fmt, ...)
{
va_list ap;
}
-/*
- * print out error message and exit
- */
-void
-adios (char *what, char *fmt, ...)
+/* adios is the same as advise(), but then "ends" the program.
+ * It calls advertise() with no tail to print fmt, and perhaps what, to
+ * stderr, and exits the program with an error status.
+ * Thus "[invo_name: ]fmt[[ what]: errno]\n" results.
+ * The route to exit is via the done function pointer and may not be
+ * straightforward, e.g. longjmp(3), but it must not return to adios().
+ * If it does then it's a bug and adios() will abort(3) as callers do
+ * not expect execution to continue. */
+void NORETURN
+adios (const char *what, const char *fmt, ...)
{
va_list ap;
advertise (what, NULL, fmt, ap);
va_end(ap);
done (1);
+ abort();
}
-/*
- * admonish the user
- */
+/* die is the same as adios(), but without the what as that's commonly
+ * NULL. */
+void NORETURN
+die(const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ advertise(NULL, NULL, fmt, ap);
+ va_end(ap);
+ done(1);
+ abort();
+}
+
+
+/* admonish calls advertise() with a tail indicating the program
+ * continues.
+ * Thus "[invo_name: ]fmt[[ what]: errno], continuing...\n" results. */
void
admonish (char *what, char *fmt, ...)
{
}
-/*
- * main routine for printing error messages.
- *
- * Use writev() if available, for slightly better performance.
- * Why? Well, there are a couple of reasons. Primarily, it
- * gives a smoother output... More importantly though, it's a
- * sexy syscall()...
- */
+/* advertise prints fmt and ap to stderr after flushing stdout.
+ * If invo_name isn't NULL or empty then "invo_name: " precedes fmt.
+ * If what isn't NULL or empty then " what" is appended.
+ * If what isn't NULL then ": errno" is appended.
+ * If tail isn't NULL or empty then ", tail" is appended.
+ * A "\n" finishes the output to stderr.
+ * In summary: "[invo_name: ]fmt[[ what]: errno][, tail]\n". */
void
-advertise (char *what, char *tail, char *fmt, va_list ap)
+advertise (const char *what, char *tail, const char *fmt, va_list ap)
{
int eindex = errno;
+ char buffer[NMH_BUFSIZ], *err;
+ struct iovec iob[10], *iov;
+ size_t niov;
-#ifdef HAVE_WRITEV
- char buffer[BUFSIZ], err[BUFSIZ];
- struct iovec iob[20], *iov;
-#endif
+ iov = iob;
- fflush (stdout);
+#define APPEND_IOV(p, len) \
+ iov->iov_base = (p); \
+ iov->iov_len = (len); \
+ iov++
-#ifdef HAVE_WRITEV
- fflush (stderr);
- iov = iob;
+#define ADD_LITERAL(s) APPEND_IOV((s), LEN(s))
+#define ADD_VAR(s) APPEND_IOV((s), strlen(s))
if (invo_name && *invo_name) {
- iov->iov_len = strlen (iov->iov_base = invo_name);
- iov++;
- iov->iov_len = strlen (iov->iov_base = ": ");
- iov++;
+ ADD_VAR(invo_name);
+ ADD_LITERAL(": ");
}
vsnprintf (buffer, sizeof(buffer), fmt, ap);
- iov->iov_len = strlen (iov->iov_base = buffer);
- iov++;
+ ADD_VAR(buffer);
if (what) {
if (*what) {
- iov->iov_len = strlen (iov->iov_base = " ");
- iov++;
- iov->iov_len = strlen (iov->iov_base = what);
- iov++;
- iov->iov_len = strlen (iov->iov_base = ": ");
- iov++;
+ ADD_LITERAL(" ");
+ ADD_VAR((void *)what);
}
- if (!(iov->iov_base = strerror (eindex))) {
- /* this shouldn't happen, but we'll test for it just in case */
- snprintf (err, sizeof(err), "Error %d", eindex);
- iov->iov_base = err;
- }
- iov->iov_len = strlen (iov->iov_base);
- iov++;
+ ADD_LITERAL(": ");
+ err = strerror(eindex);
+ ADD_VAR(err);
}
if (tail && *tail) {
- iov->iov_len = strlen (iov->iov_base = ", ");
- iov++;
- iov->iov_len = strlen (iov->iov_base = tail);
- iov++;
+ ADD_LITERAL(", ");
+ ADD_VAR(tail);
}
- iov->iov_len = strlen (iov->iov_base = "\n");
- iov++;
- writev (fileno (stderr), iob, iov - iob);
-#else
- if (invo_name && *invo_name)
- fprintf (stderr, "%s: ", invo_name);
- vfprintf (stderr, fmt, ap);
+ ADD_LITERAL("\n");
- if (what) {
- char *s;
-
- if (*what)
- fprintf (stderr, " %s: ", what);
- if ((s = strerror(eindex)))
- fprintf (stderr, "%s", s);
- else
- fprintf (stderr, "Error %d", eindex);
+#undef ADD_LITERAL
+#undef ADD_VAR
+
+ niov = iov - iob;
+ assert(niov <= DIM(iob));
+
+ fflush (stdout);
+ fflush (stderr);
+ if (writev(fileno(stderr), iob, niov) == -1) {
+ snprintf(buffer, sizeof buffer, "%s: write stderr failed: %d\n",
+ invo_name && *invo_name ? invo_name : "nmh", errno);
+ if (write(2, buffer, strlen(buffer)) == -1) {
+ /* Ignore. if-statement needed to shut up compiler. */
+ }
}
- if (tail)
- fprintf (stderr, ", %s", tail);
- fputc ('\n', stderr);
-#endif
}
projects / nmh / blobdiff