X-Git-Url: https://git.xinqibao.xyz/slstatus.git/blobdiff_plain/faa52bdcc0221de2d8fae950e409a8ac5e05bfcd..80fc20d1d69b14f36ad9bb64d8af38481cbf1ff5:/util.c?ds=inline

diff --git a/util.c b/util.c
index 6008ffc..08f14ff 100644
--- a/util.c
+++ b/util.c
@@ -2,23 +2,66 @@
 #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;
-	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) {
+		warn("vsnprintf:");
+	} else if ((size_t)ret >= sizeof(buf)) {
+		warn("vsnprintf: Output truncated");
+	}
 	va_end(ap);
 
-	if (len >= sizeof(buf))
-		buf[sizeof(buf)-1] = '\0';
-
 	return buf;
 }
 
@@ -30,7 +73,7 @@ pscanf(const char *path, const char *fmt, ...)
 	int n;
 
 	if (!(fp = fopen(path, "r"))) {
-		fprintf(stderr, "fopen '%s': %s\n", path, strerror(errno));
+		warn("fopen '%s':", path);
 		return -1;
 	}
 	va_start(ap, fmt);