fast-import: Don't use a maybe-clobbered errno value

diff --git a/strbuf.c b/strbuf.c
index dbd8c4bcfb2f8549b8713a8d9fbbfd8adcd0088c..5efcfc8860a82766b53a0d579fbdd0844d0f9b62 100644 (file)
--- a/strbuf.c
+++ b/strbuf.c
@@ -1,5 +1,14 @@
 #include "cache.h"
 
+int prefixcmp(const char *str, const char *prefix)
+{
+       for (; ; str++, prefix++)
+               if (!*prefix)
+                       return 0;
+               else if (*str != *prefix)
+                       return (unsigned char)*prefix - (unsigned char)*str;
+}
+
 /*
  * Used as the default ->buf value, so that people can always assume
  * buf is non NULL and ->buf is NUL terminated even for a freshly
@@ -118,12 +127,13 @@ void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
        int len;
        va_list ap;
 
+       if (!strbuf_avail(sb))
+               strbuf_grow(sb, 64);
        va_start(ap, fmt);
        len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
        va_end(ap);
-       if (len < 0) {
-               len = 0;
-       }
+       if (len < 0)
+               die("your vsnprintf is broken");
        if (len > strbuf_avail(sb)) {
                strbuf_grow(sb, len);
                va_start(ap, fmt);