hook.c: add a hook_exists() wrapper and use it in bugreport.c

Add a boolean version of the find_hook() function for those callers
who are only interested in checking whether the hook exists, not what
the path to it is.

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/bugreport.c

@@ -82,7 +82,7 @@ static void get_populated_hooks(struct strbuf *hook_info, int nongit)
 	}
 
 	for (i = 0; i < ARRAY_SIZE(hook); i++)
-		if (find_hook(hook[i]))
+		if (hook_exists(hook[i]))
 			strbuf_addf(hook_info, "%s\n", hook[i]);
 }
 

hook.c

@@ -35,3 +35,8 @@ const char *find_hook(const char *name)
 	}
 	return path.buf;
 }
+
+int hook_exists(const char *name)
+{
+	return !!find_hook(name);
+}

hook.h

@@ -8,4 +8,9 @@
  */
 const char *find_hook(const char *name);
 
+/**
+ * A boolean version of find_hook()
+ */
+int hook_exists(const char *hookname);
+
 #endif