Properly handle *snprintf() errors

[slstatus.git] / util.c

diff --git a/util.c b/util.c
index 67b692a..6113049 100644 (file)
--- a/util.c
+++ b/util.c
@@ -1,5 +1,4 @@
 /* See LICENSE file for copyright and license details. */
-#include <err.h>
 #include <errno.h>
 #include <stdarg.h>
 #include <stdio.h>
@@ -11,15 +10,16 @@ const char *
 bprintf(const char *fmt, ...)
 {
        va_list ap;
-       size_t len;
+       int ret;
 
        va_start(ap, fmt);
-       len = vsnprintf(buf, sizeof(buf) - 1, fmt, ap);
+       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);
 
-       if (len >= sizeof(buf))
-               buf[sizeof(buf)-1] = '\0';
-
        return buf;
 }
 
@@ -31,7 +31,7 @@ pscanf(const char *path, const char *fmt, ...)
        int n;
 
        if (!(fp = fopen(path, "r"))) {
-               warn("fopen %s: %s\n", path, strerror(errno));
+               fprintf(stderr, "fopen '%s': %s\n", path, strerror(errno));
                return -1;
        }
        va_start(ap, fmt);