[PATCH] core.workdir config variable

[Matthias Lederhofer <matled@gmx.net>]

core.workdir is used as default value for $GIT_WORK_DIR

Signed-off-by: Matthias Lederhofer <matled@gmx.net>
---
This one replaces the 'use $GIT_DIR/workdir as working directory with
$GIT_DIR' patch and uses core.workdir instead.  This patch gets
core.workdir only for setup.c from the configuration file.  Perhaps
this should be handled in git_default_config like most other core.*
variables.

I just noticed that dying if the specified workdir is invalid can
cause trouble too:

    $ export GIT_DIR=/path/to/repository
    $ git config core.workdir /non-existent
    $ git config core.workdir ../workdir
    fatal: Unable to stat git working directory '/non-existent'

Workaround is either to edit the file manually or do:

    $ git --work-dir=. config core.workdir ../workdir

---
 Documentation/config.txt |    4 +++
 setup.c                  |   53 +++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 52 insertions(+), 5 deletions(-)

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 5408dd6..663d82d 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -162,6 +162,10 @@ repository that ends in "/.git" is assumed to be not bare (bare =
 false), while all other repositories are assumed to be bare (bare
 = true).
 
+core.workdir::
+	Directory to be used as toplevel working directory when GIT_DIR
+	is set.  This can be overriden by GIT_WORK_DIR.
+
 core.logAllRefUpdates::
 	Updates to a ref <ref> is logged to the file
 	"$GIT_DIR/logs/<ref>", by appending the new and old
diff --git a/setup.c b/setup.c
index ebf628e..913c4b4 100644
--- a/setup.c
+++ b/setup.c
@@ -192,6 +192,53 @@ int is_inside_git_dir(void)
 	return inside_git_dir;
 }
 
+static char **git_work_dir;
+
+static int git_workdir_config(const char *var, const char *value)
+{
+	if (!strcmp(var, "core.workdir")) {
+		strlcpy(value, *git_work_dir, PATH_MAX);
+	}
+	return 0;
+}
+
+static int stat_git_work_dir(struct stat *st)
+{
+	char workdir[PATH_MAX], cwd[PATH_MAX];
+	const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
+	const char *gitwd = getenv(GIT_WORKING_DIR_ENVIRONMENT);
+
+	if (gitwd) {
+		if (!stat(gitwd, st))
+			return 1;
+		die("Unable to stat git working directory '%s'", gitwd);
+	}
+
+	/* get workdir from config */
+	workdir[0] = '\0';
+	git_work_dir = workdir;
+	git_config(git_workdir_config);
+	git_workdir_config = NULL;
+	if (!workdir[0])
+		return 0;
+
+	/* relative path: change to gitdir for stat */
+	if (workdir[0] != '/') {
+		if (!getcwd(cwd, sizeof(cwd)) || cwd[0] != '/')
+			die("Unable to read current working directory");
+		if (chdir(gitdir))
+			die("Cannot change directory to '%s'", gitdir);
+	}
+
+	if (stat(workdir, st))
+		die("Unable to stat git working directory '%s'", workdir);
+
+	if (workdir[0] != '/' && chdir(cwd))
+		die("Cannot come back to cwd");
+
+	return 1;
+}
+
 int has_working_directory = -1;
 
 const char *setup_git_directory_gently(int *nongit_ok)
@@ -203,7 +250,6 @@ const char *setup_git_directory_gently(int *nongit_ok)
 	gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 	if (gitdirenv) {
 		struct stat st, st_work, st_git;
-		const char *gitwd;
 		char *prefix;
 		char c;
 		int len;
@@ -219,11 +265,8 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		}
 
 		/* check for working directory */
-		gitwd = getenv(GIT_WORKING_DIR_ENVIRONMENT);
-		if (!gitwd)
+		if (!stat_git_work_dir(&st_work))
 			return NULL;
-		if (stat(gitwd, &st_work))
-			die("Unable to stat git working directory '%s'", gitwd);
 		if (inside_git_dir == -1 && stat(gitdirenv, &st_git))
 			die("Unable to stat git directory");
 		if (!getcwd(cwd, sizeof(cwd)-1) || cwd[0] != '/')
-- 
1.5.0.3.970.ge984-dirty