[PATCH v2 2/3] sha1_name: get_sha1_with_context learns to follow symlinks

[dturner@twopensource.com]

From: David Turner <dturner@twitter.com>

Wire up get_sha1_with_context to call get_tree_entry_follow_symlinks
when GET_SHA1_FOLLOW_SYMLINKS is passed in flags. G_S_FOLLOW_SYMLINKS
is incompatible with G_S_ONLY_TO_DIE because the diagnosis that
ONLY_TO_DIE triggers does not consider symlinks.

Signed-off-by: David Turner <dturner@twitter.com>
---
 cache.h     | 15 ++++++++-------
 sha1_name.c | 24 ++++++++++++++++--------
 2 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/cache.h b/cache.h
index 3d3244b..16743de 100644
--- a/cache.h
+++ b/cache.h
@@ -924,13 +924,14 @@ struct object_context {
 	unsigned mode;
 };
 
-#define GET_SHA1_QUIETLY        01
-#define GET_SHA1_COMMIT         02
-#define GET_SHA1_COMMITTISH     04
-#define GET_SHA1_TREE          010
-#define GET_SHA1_TREEISH       020
-#define GET_SHA1_BLOB	       040
-#define GET_SHA1_ONLY_TO_DIE 04000
+#define GET_SHA1_QUIETLY           01
+#define GET_SHA1_COMMIT            02
+#define GET_SHA1_COMMITTISH        04
+#define GET_SHA1_TREE             010
+#define GET_SHA1_TREEISH          020
+#define GET_SHA1_BLOB             040
+#define GET_SHA1_FOLLOW_SYMLINKS 0100
+#define GET_SHA1_ONLY_TO_DIE    04000
 
 extern int get_sha1(const char *str, unsigned char *sha1);
 extern int get_sha1_commit(const char *str, unsigned char *sha1);
diff --git a/sha1_name.c b/sha1_name.c
index 6d10f05..cbe679e 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -1434,15 +1434,21 @@ static int get_sha1_with_context_1(const char *name,
 			new_filename = resolve_relative_path(filename);
 			if (new_filename)
 				filename = new_filename;
-			ret = get_tree_entry(tree_sha1, filename, sha1, &oc->mode);
-			if (ret && only_to_die) {
-				diagnose_invalid_sha1_path(prefix, filename,
-							   tree_sha1,
-							   name, len);
+			if (flags & GET_SHA1_FOLLOW_SYMLINKS) {
+				ret = get_tree_entry_follow_symlinks(tree_sha1,
+					filename, sha1, oc->path, &oc->mode);
+			} else {
+				ret = get_tree_entry(tree_sha1, filename,
+						     sha1, &oc->mode);
+				if (ret && only_to_die) {
+					diagnose_invalid_sha1_path(prefix,
+								   filename,
+								   tree_sha1,
+								   name, len);
+				}
+				hashcpy(oc->tree, tree_sha1);
+				strlcpy(oc->path, filename, sizeof(oc->path));
 			}
-			hashcpy(oc->tree, tree_sha1);
-			strlcpy(oc->path, filename, sizeof(oc->path));
-
 			free(new_filename);
 			return ret;
 		} else {
@@ -1469,5 +1475,7 @@ void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
 
 int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc)
 {
+	if (flags & GET_SHA1_FOLLOW_SYMLINKS && flags & GET_SHA1_ONLY_TO_DIE)
+		die("BUG: incompatible flags for get_sha1_with_context");
 	return get_sha1_with_context_1(str, flags, NULL, sha1, orc);
 }
-- 
2.0.4.315.gad8727a-twtrsrc