Fix diff-tree recursion.

And, perhaps more importantly, fix the fact that if a filename changed from a
directory to a file (or vice versa), we must consider it a delete and an add,
not a "filechange".

diff --git a/diff-tree.c b/diff-tree.c
index 32d0fe1..5cf6057 100644 (file)
--- a/diff-tree.c
+++ b/diff-tree.c
@@ -28,11 +28,51 @@ static const unsigned char *extract(void *tree, unsigned long size, const char *
        return sha1;
 }
 
+static char *malloc_base(const char *base, const char *path, int pathlen)
+{
+       int baselen = strlen(base);
+       char *newbase = malloc(baselen + pathlen + 2);
+       memcpy(newbase, base, baselen);
+       memcpy(newbase + baselen, path, pathlen);
+       memcpy(newbase + baselen + pathlen, "/", 2);
+       return newbase;
+}
+
+static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
+
+/* A whole sub-tree went away or appeared */
+static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
+{
+       while (size) {
+               show_file(prefix, tree, size, base);
+               update_tree_entry(&tree, &size);
+       }
+}
+
+/* A file entry went away or appeared */
 static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
 {
        unsigned mode;
        const char *path;
        const unsigned char *sha1 = extract(tree, size, &path, &mode);
+
+       if (recursive && S_ISDIR(mode)) {
+               char type[20];
+               unsigned long size;
+               char *newbase = malloc_base(base, path, strlen(path));
+               void *tree;
+
+               tree = read_sha1_file(sha1, type, &size);
+               if (!tree || strcmp(type, "tree"))
+                       usage("corrupt tree sha %s", sha1_to_hex(sha1));
+
+               show_tree(prefix, tree, size, newbase);
+               
+               free(tree);
+               free(newbase);
+               return;
+       }
+
        printf("%s%o %s %s%s%c", prefix, mode, sha1_to_hex(sha1), base, path, 0);
 }
 
@@ -60,13 +100,20 @@ static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, uns
        }
        if (!memcmp(sha1, sha2, 20) && mode1 == mode2)
                return 0;
-       if (recursive && S_ISDIR(mode1) && S_ISDIR(mode2)) {
+
+       /*
+        * If the filemode has changed to/from a directory from/to a regular
+        * file, we need to consider it a remove and an add. 
+        */
+       if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
+               show_file("-", tree1, size1, base);
+               show_file("+", tree2, size2, base);
+               return 0;
+       }
+
+       if (recursive && S_ISDIR(mode1)) {
                int retval;
-               int baselen = strlen(base);
-               char *newbase = malloc(baselen + pathlen1 + 2);
-               memcpy(newbase, base, baselen);
-               memcpy(newbase + baselen, path1, pathlen1);
-               memcpy(newbase + baselen + pathlen1, "/", 2);
+               char *newbase = malloc_base(base, path1, pathlen1);
                retval = diff_tree_sha1(sha1, sha2, newbase);
                free(newbase);
                return retval;