util.c
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/* See LICENSE file for copyright and license details. */
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "util.h"
char *argv0;
static void
verr(const char *fmt, va_list ap)
{
if (argv0 && strncmp(fmt, "usage", sizeof("usage") - 1)) {
fprintf(stderr, "%s: ", argv0);
}
vfprintf(stderr, fmt, ap);
if (fmt[0] && fmt[strlen(fmt) - 1] == ':') {
fputc(' ', stderr);
perror(NULL);
} else {
fputc('\n', stderr);
}
}
void
warn(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
verr(fmt, ap);
va_end(ap);
}
void
die(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
verr(fmt, ap);
va_end(ap);
exit(1);
}
const char *
bprintf(const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
if ((ret = vsnprintf(buf, sizeof(buf), fmt, ap)) < 0) {
warn("vsnprintf:");
} else if ((size_t)ret >= sizeof(buf)) {
warn("vsnprintf: Output truncated");
}
va_end(ap);
return buf;
}
int
pscanf(const char *path, const char *fmt, ...)
{
FILE *fp;
va_list ap;
int n;
if (!(fp = fopen(path, "r"))) {
warn("fopen '%s':", path);
return -1;
}
va_start(ap, fmt);
n = vfscanf(fp, fmt, ap);
va_end(ap);
fclose(fp);
return (n == EOF) ? -1 : n;
}