[PATCH] diff-tree usage

diff --git a/diff-tree.c b/diff-tree.c
index 32d0fe1a1971897626457e50fcefcb6cea862025..4b9438c2937f52c93c268d4b82c9d821064d2ae9 100644 (file)
--- a/diff-tree.c
+++ b/diff-tree.c
@@ -11,7 +11,7 @@ static void update_tree_entry(void **bufp, unsigned long *sizep)
        int len = strlen(buf) + 1 + 20;
 
        if (size < len)
-               usage("corrupt tree file");
+               die("corrupt tree file");
        *bufp = buf + len;
        *sizep = size - len;
 }
@@ -23,16 +23,56 @@ static const unsigned char *extract(void *tree, unsigned long size, const char *
        const char *path = strchr(tree, ' ');
 
        if (!path || size < len + 20 || sscanf(tree, "%o", modep) != 1)
-               usage("corrupt tree file");
+               die("corrupt tree file");
        *pathp = path+1;
        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"))
+                       die("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;
@@ -101,7 +148,7 @@ static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned lon
                        update_tree_entry(&tree2, &size2);
                        continue;
                }
-               usage("diff-tree: internal error");
+               die("diff-tree: internal error");
        }
        return 0;
 }
@@ -115,10 +162,10 @@ static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, co
 
        tree1 = read_sha1_file(old, type, &size1);
        if (!tree1 || strcmp(type, "tree"))
-               usage("unable to read source tree");
+               die("unable to read source tree (%s)", sha1_to_hex(old));
        tree2 = read_sha1_file(new, type, &size2);
        if (!tree2 || strcmp(type, "tree"))
-               usage("unable to read destination tree");
+               die("unable to read destination tree (%s)", sha1_to_hex(new));
        retval = diff_tree(tree1, size1, tree2, size2, base);
        free(tree1);
        free(tree2);
@@ -133,11 +180,11 @@ int main(int argc, char **argv)
                char *arg = argv[1];
                argv++;
                argc--;
-               if (!strcmp(arg, "-R")) {
+               if (!strcmp(arg, "-r")) {
                        recursive = 1;
                        continue;
                }
-               usage("diff-tree [-R] <tree sha1> <tree sha1>");
+               usage("diff-tree [-r] <tree sha1> <tree sha1>");
        }
 
        if (argc != 3 || get_sha1_hex(argv[1], old) || get_sha1_hex(argv[2], new))