Rename warn() to warning() to fix symbol conflicts on BSD and Mac OS

This fixes a problem reported by Randal Schwartz:

>I finally tracked down all the (albeit inconsequential) errors I was getting
>on both OpenBSD and OSX.  It's the warn() function in usage.c.  There's
>warn(3) in BSD-style distros.  It'd take a "great rename" to change it, but if
>someone with better C skills than I have could do that, my linker and I would
>appreciate it.

It was annoying to me, too, when I was doing some mergetool testing on
Mac OS X, so here's a fix.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Randal L. Schwartz" <merlyn@stonehenge.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

builtin-bundle.c

@@ -87,7 +87,7 @@ static int read_header(const char *path, struct bundle_header *header) {
 		if (buffer[len - 1] == '\n')
 			buffer[len - 1] = '\0';
 		if (get_sha1_hex(buffer + offset, sha1)) {
-			warn("unrecognized header: %s", buffer);
+			warning("unrecognized header: %s", buffer);
 			continue;
 		}
 		delim = buffer[40 + offset];
@@ -268,7 +268,7 @@ static int create_bundle(struct bundle_header *header, const char *path,
 		 * from getting output.
 		 */
 		if (!(e->item->flags & SHOWN)) {
-			warn("ref '%s' is excluded by the rev-list options",
+			warning("ref '%s' is excluded by the rev-list options",
 				e->name);
 			continue;
 		}

fast-import.c

@@ -1312,7 +1312,7 @@ static int update_branch(struct branch *b)
 
 		if (!in_merge_bases(old_cmit, &new_cmit, 1)) {
 			unlock_ref(lock);
-			warn("Not updating %s"
+			warning("Not updating %s"
 				" (new tip %s does not contain %s)",
 				b->name, sha1_to_hex(b->sha1), sha1_to_hex(old_sha1));
 			return -1;

git-compat-util.h

@@ -87,7 +87,7 @@
 extern void usage(const char *err) NORETURN;
 extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
-extern void warn(const char *err, ...) __attribute__((format (printf, 1, 2)));
+extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 
 extern void set_usage_routine(void (*routine)(const char *err) NORETURN);
 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);

revision.c

@@ -486,7 +486,7 @@ static void handle_one_reflog_commit(unsigned char *sha1, void *cb_data)
 			add_pending_object(cb->all_revs, o, "");
 		}
 		else if (!cb->warned_bad_reflog) {
-			warn("reflog of '%s' references pruned commits",
+			warning("reflog of '%s' references pruned commits",
 				cb->name_for_errormsg);
 			cb->warned_bad_reflog = 1;
 		}

usage.c

@@ -86,7 +86,7 @@ int error(const char *err, ...)
 	return -1;
 }
 
-void warn(const char *warn, ...)
+void warning(const char *warn, ...)
 {
 	va_list params;