Add platform-independent .git "symlink"
This patch allows .git to be a regular textfile containing the path of
the real git directory (prefixed with "gitdir: "), which can be useful on
platforms lacking support for real symlinks.
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/repository-layout.txt b/Documentation/repository-layout.txt
index 6939130..bbaed2e 100644
--- a/Documentation/repository-layout.txt
+++ b/Documentation/repository-layout.txt
@@ -3,7 +3,10 @@
You may find these things in your git repository (`.git`
directory for a repository associated with your working tree, or
-`'project'.git` directory for a public 'bare' repository).
+`'project'.git` directory for a public 'bare' repository. It is
+also possible to have a working tree where `.git` is a plain
+ascii file containing `gitdir: <path>`, i.e. the path to the
+real git repository).
objects::
Object store associated with this repository. Usually
diff --git a/cache.h b/cache.h
index 2a1e7ec..2bda40c 100644
--- a/cache.h
+++ b/cache.h
@@ -311,6 +311,7 @@
extern char *get_graft_file(void);
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);
#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
diff --git a/environment.c b/environment.c
index 6739a3f..fcd1ee5 100644
--- a/environment.c
+++ b/environment.c
@@ -50,6 +50,8 @@
{
git_dir = getenv(GIT_DIR_ENVIRONMENT);
if (!git_dir)
+ git_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
+ if (!git_dir)
git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
git_object_dir = getenv(DB_ENVIRONMENT);
if (!git_object_dir) {
diff --git a/setup.c b/setup.c
index 3d2d958..53580fd 100644
--- a/setup.c
+++ b/setup.c
@@ -315,6 +315,44 @@
}
/*
+ * Try to read the location of the git directory from the .git file,
+ * return path to git directory if found.
+ */
+const char *read_gitfile_gently(const char *path)
+{
+ char *buf;
+ struct stat st;
+ int fd;
+ size_t len;
+
+ if (stat(path, &st))
+ return NULL;
+ if (!S_ISREG(st.st_mode))
+ return NULL;
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ die("Error opening %s: %s", path, strerror(errno));
+ buf = xmalloc(st.st_size + 1);
+ len = read_in_full(fd, buf, st.st_size);
+ close(fd);
+ if (len != st.st_size)
+ die("Error reading %s", path);
+ buf[len] = '\0';
+ if (prefixcmp(buf, "gitdir: "))
+ die("Invalid gitfile format: %s", path);
+ while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
+ len--;
+ if (len < 9)
+ die("No path in gitfile: %s", path);
+ buf[len] = '\0';
+ if (!is_git_directory(buf + 8))
+ die("Not a git repository: %s", buf + 8);
+ path = make_absolute_path(buf + 8);
+ free(buf);
+ return path;
+}
+
+/*
* We cannot decide in this function whether we are in the work tree or
* not, since the config can only be read _after_ this function was called.
*/
@@ -323,6 +361,7 @@
const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
static char cwd[PATH_MAX+1];
const char *gitdirenv;
+ const char *gitfile_dir;
int len, offset;
/*
@@ -377,8 +416,10 @@
/*
* Test in the following order (relative to the cwd):
+ * - .git (file containing "gitdir: <path>")
* - .git/
* - ./ (bare)
+ * - ../.git
* - ../.git/
* - ../ (bare)
* - ../../.git/
@@ -386,6 +427,12 @@
*/
offset = len = strlen(cwd);
for (;;) {
+ gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
+ if (gitfile_dir) {
+ if (set_git_dir(gitfile_dir))
+ die("Repository setup failed");
+ break;
+ }
if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
break;
if (is_git_directory(".")) {
diff --git a/t/t0002-gitfile.sh b/t/t0002-gitfile.sh
new file mode 100755
index 0000000..c5dbc72
--- /dev/null
+++ b/t/t0002-gitfile.sh
@@ -0,0 +1,103 @@
+#!/bin/sh
+
+test_description='.git file
+
+Verify that plumbing commands work when .git is a file
+'
+. ./test-lib.sh
+
+objpath() {
+ echo "$1" | sed -e 's|\(..\)|\1/|'
+}
+
+objck() {
+ p=$(objpath "$1")
+ if test ! -f "$REAL/objects/$p"
+ then
+ echo "Object not found: $REAL/objects/$p"
+ false
+ fi
+}
+
+
+test_expect_success 'initial setup' '
+ REAL="$(pwd)/.real" &&
+ mv .git "$REAL"
+'
+
+test_expect_success 'bad setup: invalid .git file format' '
+ echo "gitdir $REAL" >.git &&
+ if git rev-parse 2>.err
+ then
+ echo "git rev-parse accepted an invalid .git file"
+ false
+ fi &&
+ if ! grep -qe "Invalid gitfile format" .err
+ then
+ echo "git rev-parse returned wrong error"
+ false
+ fi
+'
+
+test_expect_success 'bad setup: invalid .git file path' '
+ echo "gitdir: $REAL.not" >.git &&
+ if git rev-parse 2>.err
+ then
+ echo "git rev-parse accepted an invalid .git file path"
+ false
+ fi &&
+ if ! grep -qe "Not a git repository" .err
+ then
+ echo "git rev-parse returned wrong error"
+ false
+ fi
+'
+
+test_expect_success 'final setup + check rev-parse --git-dir' '
+ echo "gitdir: $REAL" >.git &&
+ test "$REAL" = "$(git rev-parse --git-dir)"
+'
+
+test_expect_success 'check hash-object' '
+ echo "foo" >bar &&
+ SHA=$(cat bar | git hash-object -w --stdin) &&
+ objck $SHA
+'
+
+test_expect_success 'check cat-file' '
+ git cat-file blob $SHA >actual &&
+ diff -u bar actual
+'
+
+test_expect_success 'check update-index' '
+ if test -f "$REAL/index"
+ then
+ echo "Hmm, $REAL/index exists?"
+ false
+ fi &&
+ rm -f "$REAL/objects/$(objpath $SHA)" &&
+ git update-index --add bar &&
+ if ! test -f "$REAL/index"
+ then
+ echo "$REAL/index not found"
+ false
+ fi &&
+ objck $SHA
+'
+
+test_expect_success 'check write-tree' '
+ SHA=$(git write-tree) &&
+ objck $SHA
+'
+
+test_expect_success 'check commit-tree' '
+ SHA=$(echo "commit bar" | git commit-tree $SHA) &&
+ objck $SHA
+'
+
+test_expect_success 'check rev-list' '
+ echo $SHA >"$REAL/HEAD" &&
+ test "$SHA" = "$(git rev-list HEAD)"
+'
+
+test_done
