[PATCH 2/3] Teach read_tree_recursive() how to traverse into submodules

From

LHLars Hjemli <hjemli@gmail.com>

Date

Jan 18, 2009, 10:53 UTC

Message-ID

<1232275999-14852-3-git-send-email-hjemli@gmail.com>

In-Reply-To

<1232275999-14852-2-git-send-email-hjemli@gmail.com>

Signed-off-by: Lars Hjemli <hjemli@gmail.com>
---
 cache.h       |    2 +
 environment.c |   12 ++++++++
 tree.c        |   80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 94 insertions(+), 0 deletions(-)

diff --git a/cache.h b/cache.h
index daa2d4e..6728467 100644
--- a/cache.h
+++ b/cache.h
@@ -382,6 +382,8 @@ extern int set_git_dir(const char *path);
 extern const char *get_git_work_tree(void);
 extern const char *read_gitfile_gently(const char *path);
 extern void set_git_work_tree(const char *tree);
+extern int get_traverse_gitlinks();
+extern void set_traverse_gitlinks(int traverse);
 
 #define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 
diff --git a/environment.c b/environment.c
index e278bce..35cc557 100644
--- a/environment.c
+++ b/environment.c
@@ -53,6 +53,8 @@ static char *work_tree;
 static const char *git_dir;
 static char *git_object_dir, *git_index_file, *git_refs_dir, *git_graft_file;
 
+static int traverse_gitlinks = 0;
+
 static void setup_git_env(void)
 {
 	git_dir = getenv(GIT_DIR_ENVIRONMENT);
@@ -159,3 +161,13 @@ int set_git_dir(const char *path)
 	setup_git_env();
 	return 0;
 }
+
+int get_traverse_gitlinks()
+{
+	return traverse_gitlinks;
+}
+
+void set_traverse_gitlinks(int traverse)
+{
+	traverse_gitlinks = traverse;
+}
diff --git a/tree.c b/tree.c
index 03e782a..87cf309 100644
--- a/tree.c
+++ b/tree.c
@@ -5,6 +5,7 @@
 #include "commit.h"
 #include "tag.h"
 #include "tree-walk.h"
+#include "refs.h"
 
 const char *tree_type = "tree";
 
@@ -89,6 +90,61 @@ static int match_tree_entry(const char *base, int baselen, const char *path, uns
 	return 0;
 }
 
+/* Try to add the objectdb of a submodule */
+int add_gitlink_odb(char *relpath)
+{
+	const char *odbpath;
+	struct stat st;
+
+	odbpath = read_gitfile_gently(mkpath("%s/.git", relpath));
+	if (!odbpath)
+		odbpath = mkpath("%s/.git/objects", relpath);
+
+	if (stat(odbpath, &st))
+		return 1;
+
+	return add_alt_odb(odbpath);
+}
+
+/* Check if we should recurse into the specified submodule */
+int traverse_gitlink(char *path, const unsigned char *commit_sha1,
+		     struct tree **subtree)
+{
+	unsigned char sha1[20];
+	int linked_odb = 0;
+	struct commit *commit;
+	void *buffer;
+	enum object_type type;
+	unsigned long size;
+
+	hashcpy(sha1, commit_sha1);
+	if (!add_gitlink_odb(path)) {
+		linked_odb = 1;
+		if (resolve_gitlink_ref(path, "HEAD", sha1))
+			die("Unable to lookup HEAD in %s", path);
+	}
+
+	buffer = read_sha1_file(sha1, &type, &size);
+	if (!buffer) {
+		if (linked_odb)
+			die("Unable to read object %s in submodule %s",
+			    sha1_to_hex(sha1), path);
+		else
+			return 0;
+	}
+
+	commit = lookup_commit(sha1);
+	if (!commit)
+		die("traverse_gitlink(): internal error");
+
+	if (parse_commit_buffer(commit, buffer, size))
+		die("Failed to parse commit %s in submodule %s",
+		    sha1_to_hex(sha1), path);
+
+	*subtree = commit->tree;
+	return 1;
+}
+
 int read_tree_recursive(struct tree *tree,
 			const char *base, int baselen,
 			int stage, const char **match,
@@ -132,6 +188,30 @@ int read_tree_recursive(struct tree *tree,
 				return -1;
 			continue;
 		}
+		if (S_ISGITLINK(entry.mode) && get_traverse_gitlinks()) {
+			int retval;
+			char *newbase;
+			struct tree *subtree;
+			unsigned int pathlen = tree_entry_len(entry.path, entry.sha1);
+
+			newbase = xmalloc(baselen + 1 + pathlen);
+			memcpy(newbase, base, baselen);
+			memcpy(newbase + baselen, entry.path, pathlen);
+			newbase[baselen + pathlen] = 0;
+			if (!traverse_gitlink(newbase, entry.sha1, &subtree)) {
+				free(newbase);
+				continue;
+			}
+			newbase[baselen + pathlen] = '/';
+			retval = read_tree_recursive(subtree,
+						     newbase,
+						     baselen + pathlen + 1,
+						     stage, match, fn, context);
+			free(newbase);
+			if (retval)
+				return -1;
+			continue;
+		}
 	}
 	return 0;
 }

-- 
1.6.1.150.g5e733b