use xsnprintf for generating git object headers

diff --git a/usage.c b/usage.c
index e4fa6d2f0315c6f5ae63c97d83bfab3a14e279b2..82ff13163b542aab07e68bfa1056dc46316634a1 100644 (file)
--- a/usage.c
+++ b/usage.c
@@ -7,13 +7,21 @@
 #include "cache.h"
 
 static FILE *error_handle;
+static int tweaked_error_buffering;
 
 void vreportf(const char *prefix, const char *err, va_list params)
 {
-       char msg[4096];
        FILE *fh = error_handle ? error_handle : stderr;
-       vsnprintf(msg, sizeof(msg), err, params);
-       fprintf(fh, "%s%s\n", prefix, msg);
+
+       fflush(fh);
+       if (!tweaked_error_buffering) {
+               setvbuf(fh, NULL, _IOLBF, 0);
+               tweaked_error_buffering = 1;
+       }
+
+       fputs(prefix, fh);
+       vfprintf(fh, err, params);
+       fputc('\n', fh);
 }
 
 static NORETURN void usage_builtin(const char *err, va_list params)
@@ -70,6 +78,7 @@ void set_die_is_recursing_routine(int (*routine)(void))
 void set_error_handle(FILE *fh)
 {
        error_handle = fh;
+       tweaked_error_buffering = 0;
 }
 
 void NORETURN usagef(const char *err, ...)