[PATCH] Support precise tracking of file modes

[Petr Baudis <pasky@suse.cz>]

Dear diary, on Thu, Jan 19, 2006 at 08:50:22AM CET, I got a letter
where Junio C Hamano <junkio@cox.net> said that...
> Ryan Anderson <ryan@michonline.com> writes:
> 
> > Junio C Hamano wrote:
> >> Adam Hunt <kinema@gmail.com> writes:
> >> 
> >> 
> >>>Do you have any more details by chance?  Does it work?  Does it work
> >>>well?  How does one do it?
> >> 
> >> 
> >> I personally feel it is a horrible and stupid thing to do, if by
> >> "version control /etc" you mean to have /.git which controls
> >> /etc/hosts and stuff in place.  It would work (git does not
> >> refuse to run as root).  But being a *source* control system, we
> >> deliberately refuse to store the full permission bits, so if
> >> your /etc/shadow is mode 0600 while /etc/hosts is mode 0644, you
> >> have to make sure they stay that way after checking things out.
> >
> > This is, admittedly, a major problem.
> 
> An SCM is not a replacement of a backup.

It seems that this is mostly an artificial imposition and it's annoying.
Hey, I need to leave for an exam in 15 minutes and I have few urgent
items in my Cogito TODO (sorry, Pavel!), but I couldn't resist.

Taking "quick'n'dirty" to the extreme _and_ combining it with Linus'
attitude to testing and documentation... ;-)

diff --git a/cache.h b/cache.h
index 29c9e81..0311066 100644
--- a/cache.h
+++ b/cache.h
@@ -94,7 +94,9 @@ struct cache_entry {
 #define ce_size(ce) cache_entry_size(ce_namelen(ce))
 #define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
 
-#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
+extern int track_filemode;
+
+#define ce_permissions(mode) (track_filemode ? (mode) : (((mode) & 0100) ? 0755 : 0644))
 static inline unsigned int create_ce_mode(unsigned int mode)
 {
 	if (S_ISLNK(mode))
diff --git a/checkout-index.c b/checkout-index.c
index 53dd8cb..b073baa 100644
--- a/checkout-index.c
+++ b/checkout-index.c
@@ -115,6 +115,8 @@ int main(int argc, char **argv)
 	int newfd = -1;
 	int all = 0;
 
+	git_config(git_default_config);
+
 	prefix = setup_git_directory();
 	prefix_length = prefix ? strlen(prefix) : 0;
 
diff --git a/config.c b/config.c
index 8355224..a92ee0f 100644
--- a/config.c
+++ b/config.c
@@ -222,6 +222,11 @@ int git_default_config(const char *var, 
 		return 0;
 	}
 
+	if (!strcmp(var, "core.trackallfilemodes")) {
+		track_filemode = git_config_bool(var, value);
+		return 0;
+	}
+
 	if (!strcmp(var, "core.symrefsonly")) {
 		only_use_symrefs = git_config_bool(var, value);
 		return 0;
diff --git a/entry.c b/entry.c
index 410b758..493f2b9 100644
--- a/entry.c
+++ b/entry.c
@@ -87,6 +87,11 @@ static int write_entry(struct cache_entr
 			return error("git-checkout-index: unable to create file %s (%s)",
 				path, strerror(errno));
 		}
+		if (track_filemode) {
+			if (fchmod(fd, ntohl(ce->ce_mode)) < 0)
+				return error("git-checkout-index: unable to chmod file %s (%s)",
+					path, strerror(errno));
+		}
 		wrote = write(fd, new, size);
 		close(fd);
 		free(new);
diff --git a/environment.c b/environment.c
index 0596fc6..53248ec 100644
--- a/environment.c
+++ b/environment.c
@@ -12,6 +12,7 @@
 char git_default_email[MAX_GITNAME];
 char git_default_name[MAX_GITNAME];
 int trust_executable_bit = 1;
+int track_filemode = 0;
 int only_use_symrefs = 0;
 int repository_format_version = 0;
 char git_commit_encoding[MAX_ENCODING_LENGTH] = "utf-8";
diff --git a/fsck-objects.c b/fsck-objects.c
index 90e638e..719add2 100644
--- a/fsck-objects.c
+++ b/fsck-objects.c
@@ -174,7 +174,8 @@ static int fsck_tree(struct tree *item)
 			if (!check_strict)
 				break;
 		default:
-			has_bad_modes = 1;
+			if (!track_filemode || (entry->mode & ~(S_IFREG|0777)))
+				has_bad_modes = 1;
 		}
 
 		if (last) {
diff --git a/read-cache.c b/read-cache.c
index c5474d4..624d2c3 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -98,7 +98,7 @@ static int ce_match_stat_basic(struct ca
 		 * "mode changes"
 		 */
 		if (trust_executable_bit &&
-		    (0100 & (ntohl(ce->ce_mode) ^ st->st_mode)))
+		    ((track_filemode ? 0777 : 0100) & (ntohl(ce->ce_mode) ^ st->st_mode)))
 			changed |= MODE_CHANGED;
 		break;
 	case S_IFLNK:


-- 
				Petr "Pasky" Baudis
Stuff: http://pasky.or.cz/
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