[PATCH] add --missing-ok option to write-tree

This option allows a write-tree even if the referenced objects are not
in the database.

Signed-off-by: Bryan Larsen <bryan.larsen@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/git-write-tree.txt

@@ -10,6 +10,7 @@ git-write-tree - Creates a tree from the current cache
 SYNOPSIS
 --------
 'git-write-tree'
+		[--missing-ok]
 
 DESCRIPTION
 -----------
@@ -23,7 +24,11 @@ In order to have that match what is actually in your directory right
 now, you need to have done a "git-update-cache" phase before you did the
 "git-write-tree".
 
-
+OPTIONS
+-------
+--missing-ok::
+	Normally "git-write-tree" ensures that the objects referenced by the
+	directory exist in the object database.  This option disables this check.
 
 
 ////////////////////////////////////////////////////////////////

write-tree.c

@@ -5,6 +5,8 @@
  */
 #include "cache.h"
 
+static int missing_ok = 0;
+
 static int check_valid_sha1(unsigned char *sha1)
 {
 	int ret;
@@ -61,7 +63,7 @@ static int write_tree(struct cache_entry **cachep, int maxentries, const char *b
 			sha1 = subdir_sha1;
 		}
 
-		if (check_valid_sha1(sha1) < 0)
+		if (!missing_ok && check_valid_sha1(sha1) < 0)
 			exit(1);
 
 		entrylen = pathlen - baselen;
@@ -86,6 +88,16 @@ int main(int argc, char **argv)
 	int i, funny;
 	int entries = read_cache();
 	unsigned char sha1[20];
+
+	if (argc==2) {
+		if (!strcmp(argv[1], "--missing-ok"))
+			missing_ok = 1;
+		else
+			die("unknown option %s", argv[1]);
+	}
+
+	if (argc>2)
+		die("too many options");
 
 	if (entries < 0)
 		die("git-write-tree: error reading cache");