usage.c: move format processing out of die_errno()

fmt_with_err() will be shared with the coming error_errno() and
warning_errno().

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 16 insertions, 11 deletions

diff --git a/usage.c b/usage.c
index 82ff13163b..8675d72f30 100644
--- a/usage.c
+++ b/usage.c
@@ -109,19 +109,11 @@ void NORETURN die(const char *err, ...)
 	va_end(params);
 }
 
-void NORETURN die_errno(const char *fmt, ...)
+static const char *fmt_with_err(char *buf, int n, const char *fmt)
 {
-	va_list params;
-	char fmt_with_err[1024];
 	char str_error[256], *err;
 	int i, j;
 
-	if (die_is_recursing()) {
-		fputs("fatal: recursion detected in die_errno handler\n",
-			stderr);
-		exit(128);
-	}
-
 	err = strerror(errno);
 	for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {
 		if ((str_error[j++] = err[i++]) != '%')
@@ -136,10 +128,23 @@ void NORETURN die_errno(const char *fmt, ...)
 		}
 	}
 	str_error[j] = 0;
-	snprintf(fmt_with_err, sizeof(fmt_with_err), "%s: %s", fmt, str_error);
+	snprintf(buf, n, "%s: %s", fmt, str_error);
+	return buf;
+}
+
+void NORETURN die_errno(const char *fmt, ...)
+{
+	char buf[1024];
+	va_list params;
+
+	if (die_is_recursing()) {
+		fputs("fatal: recursion detected in die_errno handler\n",
+			stderr);
+		exit(128);
+	}
 
 	va_start(params, fmt);
-	die_routine(fmt_with_err, params);
+	die_routine(fmt_with_err(buf, sizeof(buf), fmt), params);
 	va_end(params);
 }