1 files changed, 117 insertions, 9 deletions

diff --git a/read-cache.c b/read-cache.c
index f83de8c..525d138 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -38,6 +38,22 @@ static void replace_index_entry(struct index_state *istate, int nr, struct cache
 	istate->cache_changed = 1;
 }
 
+void rename_index_entry_at(struct index_state *istate, int nr, const char *new_name)
+{
+	struct cache_entry *old = istate->cache[nr], *new;
+	int namelen = strlen(new_name);
+
+	new = xmalloc(cache_entry_size(namelen));
+	copy_cache_entry(new, old);
+	new->ce_flags &= ~(CE_STATE_MASK | CE_NAMEMASK);
+	new->ce_flags |= (namelen >= CE_NAMEMASK ? CE_NAMEMASK : namelen);
+	memcpy(new->name, new_name, namelen + 1);
+
+	cache_tree_invalidate_path(istate->cache_tree, old->name);
+	remove_index_entry_at(istate, nr);
+	add_index_entry(istate, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
+}
+
 /*
  * This only updates the "non-critical" parts of the directory
  * cache, ie the parts that aren't tracked by GIT, and only used
@@ -131,7 +147,7 @@ static int ce_modified_check_fs(struct cache_entry *ce, struct stat *st)
 		break;
 	case S_IFDIR:
 		if (S_ISGITLINK(ce->ce_mode))
-			return 0;
+			return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
 	default:
 		return TYPE_CHANGED;
 	}
@@ -171,6 +187,7 @@ static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
 			changed |= TYPE_CHANGED;
 		break;
 	case S_IFGITLINK:
+		/* We ignore most of the st_xxx fields for gitlinks */
 		if (!S_ISDIR(st->st_mode))
 			changed |= TYPE_CHANGED;
 		else if (ce_compare_gitlink(ce))
@@ -181,7 +198,7 @@ static int ce_match_stat_basic(struct cache_entry *ce, struct stat *st)
 	}
 	if (ce->ce_mtime != (unsigned int) st->st_mtime)
 		changed |= MTIME_CHANGED;
-	if (ce->ce_ctime != (unsigned int) st->st_ctime)
+	if (trust_ctime && ce->ce_ctime != (unsigned int) st->st_ctime)
 		changed |= CTIME_CHANGED;
 
 	if (ce->ce_uid != (unsigned int) st->st_uid ||
@@ -277,11 +294,22 @@ int ie_modified(const struct index_state *istate,
 	if (changed & (MODE_CHANGED | TYPE_CHANGED))
 		return changed;
 
-	/* Immediately after read-tree or update-index --cacheinfo,
-	 * the length field is zero.  For other cases the ce_size
-	 * should match the SHA1 recorded in the index entry.
+	/*
+	 * Immediately after read-tree or update-index --cacheinfo,
+	 * the length field is zero, as we have never even read the
+	 * lstat(2) information once, and we cannot trust DATA_CHANGED
+	 * returned by ie_match_stat() which in turn was returned by
+	 * ce_match_stat_basic() to signal that the filesize of the
+	 * blob changed.  We have to actually go to the filesystem to
+	 * see if the contents match, and if so, should answer "unchanged".
+	 *
+	 * The logic does not apply to gitlinks, as ce_match_stat_basic()
+	 * already has checked the actual HEAD from the filesystem in the
+	 * subproject.  If ie_match_stat() already said it is different,
+	 * then we know it is.
 	 */
-	if ((changed & DATA_CHANGED) && ce->ce_size != 0)
+	if ((changed & DATA_CHANGED) &&
+	    (S_ISGITLINK(ce->ce_mode) || ce->ce_size != 0))
 		return changed;
 
 	changed_fs = ce_modified_check_fs(ce, st);
@@ -528,7 +556,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 		ce = create_alias_ce(ce, alias);
 	ce->ce_flags |= CE_ADDED;
 
-	/* It was suspected to be recily clean, but it turns out to be Ok */
+	/* It was suspected to be racily clean, but it turns out to be Ok */
 	was_same = (alias &&
 		    !ce_stage(alias) &&
 		    !hashcmp(alias->sha1, ce->sha1) &&
@@ -980,7 +1008,10 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p
 	int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
 	int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
 	unsigned int options = really ? CE_MATCH_IGNORE_VALID : 0;
+	const char *needs_update_message;
 
+	needs_update_message = ((flags & REFRESH_SAY_CHANGED)
+				? "locally modified" : "needs update");
 	for (i = 0; i < istate->cache_nr; i++) {
 		struct cache_entry *ce, *new;
 		int cache_errno = 0;
@@ -1019,7 +1050,7 @@ int refresh_index(struct index_state *istate, unsigned int flags, const char **p
 			}
 			if (quiet)
 				continue;
-			printf("%s: needs update\n", ce->name);
+			printf("%s: %s\n", ce->name, needs_update_message);
 			has_errors = 1;
 			continue;
 		}
@@ -1124,7 +1155,7 @@ int read_index_from(struct index_state *istate, const char *path)
 	size_t mmap_size;
 
 	errno = EBUSY;
-	if (istate->alloc)
+	if (istate->initialized)
 		return istate->cache_nr;
 
 	errno = ENOENT;
@@ -1164,6 +1195,7 @@ int read_index_from(struct index_state *istate, const char *path)
 	 * index size
 	 */
 	istate->alloc = xmalloc(estimate_cache_size(mmap_size, istate->cache_nr));
+	istate->initialized = 1;
 
 	src_offset = sizeof(*hdr);
 	dst_offset = 0;
@@ -1207,15 +1239,22 @@ unmap:
 	die("index file corrupt");
 }
 
+int is_index_unborn(struct index_state *istate)
+{
+	return (!istate->cache_nr && !istate->alloc && !istate->timestamp);
+}
+
 int discard_index(struct index_state *istate)
 {
 	istate->cache_nr = 0;
 	istate->cache_changed = 0;
 	istate->timestamp = 0;
+	istate->name_hash_initialized = 0;
 	free_hash(&istate->name_hash);
 	cache_tree_free(&(istate->cache_tree));
 	free(istate->alloc);
 	istate->alloc = NULL;
+	istate->initialized = 0;
 
 	/* no need to throw away allocated active_cache */
 	return 0;
@@ -1307,6 +1346,11 @@ static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
 	 * falsely clean entry due to touch-update-touch race, so we leave
 	 * everything else as they are.  We are called for entries whose
 	 * ce_mtime match the index file mtime.
+	 *
+	 * Note that this actually does not do much for gitlinks, for
+	 * which ce_match_stat_basic() always goes to the actual
+	 * contents.  The caller checks with is_racy_timestamp() which
+	 * always says "no" for gitlinks, so we are not called for them ;-)
 	 */
 	struct stat st;
 
@@ -1410,3 +1454,67 @@ int write_index(const struct index_state *istate, int newfd)
 	}
 	return ce_flush(&c, newfd);
 }
+
+/*
+ * Read the index file that is potentially unmerged into given
+ * index_state, dropping any unmerged entries.  Returns true is
+ * the index is unmerged.  Callers who want to refuse to work
+ * from an unmerged state can call this and check its return value,
+ * instead of calling read_cache().
+ */
+int read_index_unmerged(struct index_state *istate)
+{
+	int i;
+	int unmerged = 0;
+
+	read_index(istate);
+	for (i = 0; i < istate->cache_nr; i++) {
+		struct cache_entry *ce = istate->cache[i];
+		struct cache_entry *new_ce;
+		int size, len;
+
+		if (!ce_stage(ce))
+			continue;
+		unmerged = 1;
+		len = strlen(ce->name);
+		size = cache_entry_size(len);
+		new_ce = xcalloc(1, size);
+		hashcpy(new_ce->sha1, ce->sha1);
+		memcpy(new_ce->name, ce->name, len);
+		new_ce->ce_flags = create_ce_flags(len, 0);
+		new_ce->ce_mode = ce->ce_mode;
+		if (add_index_entry(istate, new_ce, 0))
+			return error("%s: cannot drop to stage #0",
+				     ce->name);
+		i = index_name_pos(istate, new_ce->name, len);
+	}
+	return unmerged;
+}
+
+/*
+ * Returns 1 if the path is an "other" path with respect to
+ * the index; that is, the path is not mentioned in the index at all,
+ * either as a file, a directory with some files in the index,
+ * or as an unmerged entry.
+ *
+ * We helpfully remove a trailing "/" from directories so that
+ * the output of read_directory can be used as-is.
+ */
+int index_name_is_other(const struct index_state *istate, const char *name,
+		int namelen)
+{
+	int pos;
+	if (namelen && name[namelen - 1] == '/')
+		namelen--;
+	pos = index_name_pos(istate, name, namelen);
+	if (0 <= pos)
+		return 0;	/* exact match */
+	pos = -pos - 1;
+	if (pos < istate->cache_nr) {
+		struct cache_entry *ce = istate->cache[pos];
+		if (ce_namelen(ce) == namelen &&
+		    !memcmp(ce->name, name, namelen))
+			return 0; /* Yup, this one exists unmerged */
+	}
+	return 1;
+}