replace trivial malloc + sprintf / strcpy calls with xstrfmt

It's a common pattern to do:

  foo = xmalloc(strlen(one) + strlen(two) + 1 + 1);
  sprintf(foo, "%s %s", one, two);

(or possibly some variant with strcpy()s or a more
complicated length computation).  We can switch these to use
xstrfmt, which is shorter, involves less error-prone manual
computation, and removes many sprintf and strcpy calls which
make it harder to audit the code for real buffer overflows.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 5 deletions

diff --git a/environment.c b/environment.c
index a533aed630..c5b65f5e23 100644
--- a/environment.c
+++ b/environment.c
@@ -143,11 +143,8 @@ static char *git_path_from_env(const char *envvar, const char *git_dir,
 			       const char *path, int *fromenv)
 {
 	const char *value = getenv(envvar);
-	if (!value) {
-		char *buf = xmalloc(strlen(git_dir) + strlen(path) + 2);
-		sprintf(buf, "%s/%s", git_dir, path);
-		return buf;
-	}
+	if (!value)
+		return xstrfmt("%s/%s", git_dir, path);
 	if (fromenv)
 		*fromenv = 1;
 	return xstrdup(value);