diff-tree: add "--root" flag to show a root commit as a big creation event.

[git.git] / diff-tree.c

diff --git a/diff-tree.c b/diff-tree.c
index 59d12f2..9d94e0c 100644 (file)
--- a/diff-tree.c
+++ b/diff-tree.c
@@ -3,12 +3,14 @@
 #include "diff.h"
 
 static int silent = 0;
+static int show_root_diff = 0;
 static int verbose_header = 0;
 static int ignore_merges = 1;
 static int recursive = 0;
 static int read_stdin = 0;
 static int line_termination = '\n';
 static int generate_patch = 0;
+static int detect_rename = 0;
 static const char *header = NULL;
 static const char *header_prefix = "";
 
@@ -258,7 +260,7 @@ static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned lon
                        update_tree_entry(&tree2, &size2);
                        continue;
                }
-               die("diff-tree: internal error");
+               die("git-diff-tree: internal error");
        }
        return 0;
 }
@@ -281,6 +283,36 @@ static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, co
        return retval;
 }
 
+static int diff_tree_sha1_top(const unsigned char *old,
+                             const unsigned char *new, const char *base)
+{
+       int ret;
+       if (generate_patch)
+               diff_setup(detect_rename, 0, 0, 0, 0);
+       ret = diff_tree_sha1(old, new, base);
+       if (generate_patch)
+               diff_flush();
+       return ret;
+}
+
+static int diff_root_tree(const unsigned char *new, const char *base)
+{
+       int retval;
+       void *tree;
+       unsigned long size;
+
+       if (generate_patch)
+               diff_setup(detect_rename, 0, 0, 0, 0);
+       tree = read_object_with_reference(new, "tree", &size, 0);
+       if (!tree)
+               die("unable to read root tree (%s)", sha1_to_hex(new));
+       retval = diff_tree("", 0, tree, size, base);
+       free(tree);
+       if (generate_patch)
+               diff_flush();
+       return retval;
+}
+
 static int get_one_line(const char *msg, unsigned long len)
 {
        int ret = 0;
@@ -359,25 +391,31 @@ static int diff_tree_commit(const unsigned char *commit, const char *name)
        if (!buf)
                return -1;
 
-       /* More than one parent? */
-       if (ignore_merges) {
-               if (!memcmp(buf + 46 + 48, "parent ", 7))
-                       return 0;
-       }
-
        if (!name) {
                static char commit_name[60];
                strcpy(commit_name, sha1_to_hex(commit));
                name = commit_name;
        }
 
+       /* Root commit? */
+       if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
+               header = generate_header(name, "root", buf, size);
+               diff_root_tree(commit, "");
+       }
+
+       /* More than one parent? */
+       if (ignore_merges) {
+               if (!memcmp(buf + 46 + 48, "parent ", 7))
+                       return 0;
+       }
+
        offset = 46;
        while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
                unsigned char parent[20];
                if (get_sha1_hex(buf + offset + 7, parent))
                        return -1;
                header = generate_header(name, sha1_to_hex(parent), buf, size);
-               diff_tree_sha1(parent, commit, "");
+               diff_tree_sha1_top(parent, commit, "");
                if (!header && verbose_header)
                        header_prefix = "\ndiff-tree ";
                offset += 48;
@@ -401,14 +439,14 @@ static int diff_tree_stdin(char *line)
                line[81] = 0;
                sprintf(this_header, "%s (from %s)\n", line, line+41);
                header = this_header;
-               return diff_tree_sha1(parent, commit, "");
+               return diff_tree_sha1_top(parent, commit, "");
        }
        line[40] = 0;
        return diff_tree_commit(commit, line);
 }
 
 static char *diff_tree_usage =
-"diff-tree [-p] [-r] [-z] [--stdin] [-m] [-s] [-v] <tree sha1> <tree sha1>";
+"git-diff-tree [-p] [-r] [-z] [--stdin] [-M] [-m] [-s] [-v] <tree-ish> <tree-ish>";
 
 int main(int argc, char **argv)
 {
@@ -447,6 +485,10 @@ int main(int argc, char **argv)
                        recursive = generate_patch = 1;
                        continue;
                }
+               if (!strcmp(arg, "-M")) {
+                       detect_rename = recursive = generate_patch = 1;
+                       continue;
+               }
                if (!strcmp(arg, "-z")) {
                        line_termination = '\0';
                        continue;
@@ -468,6 +510,10 @@ int main(int argc, char **argv)
                        read_stdin = 1;
                        continue;
                }
+               if (!strcmp(arg, "--root")) {
+                       show_root_diff = 1;
+                       continue;
+               }
                usage(diff_tree_usage);
        }
 
@@ -490,7 +536,7 @@ int main(int argc, char **argv)
                diff_tree_commit(sha1[0], NULL);
                break;
        case 2:
-               diff_tree_sha1(sha1[0], sha1[1], "");
+               diff_tree_sha1_top(sha1[0], sha1[1], "");
                break;
        }