slstatus/util.c
Laslo Hunhold c83b388a3f Properly handle *snprintf() errors
Posix guarantees that the resulting string is null-terminated, even if
we have an overflow. Instead of doing what has already been done,
properly warn when there has been an error or overflow, so the user can
do something about it.
2018-05-17 23:26:56 +02:00

43 lines
786 B
C

/* See LICENSE file for copyright and license details. */
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include "util.h"
const char *
bprintf(const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
if ((ret = vsnprintf(buf, sizeof(buf), fmt, ap)) < 0) {
fprintf(stderr, "vsnprintf: %s\n", strerror(errno));
} else if ((size_t)ret >= sizeof(buf)) {
fprintf(stderr, "vsnprintf: Output truncated\n");
}
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"))) {
fprintf(stderr, "fopen '%s': %s\n", path, strerror(errno));
return -1;
}
va_start(ap, fmt);
n = vfscanf(fp, fmt, ap);
va_end(ap);
fclose(fp);
return (n == EOF) ? -1 : n;
}