Merge branch 'lt/gitlink'

* lt/gitlink:
  Tests for core subproject support
  Expose subprojects as special files to "git diff" machinery
  Fix some "git ls-files -o" fallout from gitlinks
  Teach "git-read-tree -u" to check out submodules as a directory
  Teach git list-objects logic to not follow gitlinks
  Fix gitlink index entry filesystem matching
  Teach "git-read-tree -u" to check out submodules as a directory
  Teach git list-objects logic not to follow gitlinks
  Don't show gitlink directories when we want "other" files
  Teach git-update-index about gitlinks
  Teach directory traversal about subprojects
  Fix thinko in subproject entry sorting
  Teach core object handling functions about gitlinks
  Teach "fsck" not to follow subproject links
  Add "S_IFDIRLNK" file mode infrastructure for git links
  Add 'resolve_gitlink_ref()' helper function
  Avoid overflowing name buffer in deep directory structures
  diff-lib: use ce_mode_from_stat() rather than messing with modes manually

1 files changed, 19 insertions, 1 deletions

diff --git a/cache.h b/cache.h
index ead1196..8747d01 100644
--- a/cache.h
+++ b/cache.h
@@ -25,6 +25,22 @@
 #endif
 
 /*
+ * A "directory link" is a link to another git directory.
+ *
+ * The value 0160000 is not normally a valid mode, and
+ * also just happens to be S_IFDIR + S_IFLNK
+ *
+ * NOTE! We *really* shouldn't depend on the S_IFxxx macros
+ * always having the same values everywhere. We should use
+ * our internal git values for these things, and then we can
+ * translate that to the OS-specific value. It just so
+ * happens that everybody shares the same bit representation
+ * in the UNIX world (and apparently wider too..)
+ */
+#define S_IFDIRLNK	0160000
+#define S_ISDIRLNK(m)	(((m) & S_IFMT) == S_IFDIRLNK)
+
+/*
  * Intensive research over the course of many years has shown that
  * port 9418 is totally unused by anything else. Or
  *
@@ -104,6 +120,8 @@ static inline unsigned int create_ce_mode(unsigned int mode)
 {
 	if (S_ISLNK(mode))
 		return htonl(S_IFLNK);
+	if (S_ISDIR(mode) || S_ISDIRLNK(mode))
+		return htonl(S_IFDIRLNK);
 	return htonl(S_IFREG | ce_permissions(mode));
 }
 static inline unsigned int ce_mode_from_stat(struct cache_entry *ce, unsigned int mode)
@@ -121,7 +139,7 @@ static inline unsigned int ce_mode_from_stat(struct cache_entry *ce, unsigned in
 }
 #define canon_mode(mode) \
 	(S_ISREG(mode) ? (S_IFREG | ce_permissions(mode)) : \
-	S_ISLNK(mode) ? S_IFLNK : S_IFDIR)
+	S_ISLNK(mode) ? S_IFLNK : S_ISDIR(mode) ? S_IFDIR : S_IFDIRLNK)
 
 #define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)