Move "read_tree()" to "tree.c" to be used as a generic helper function.

Next step: make "diff-cache" use it.

1 files changed, 65 insertions, 0 deletions

diff --git a/tree.c b/tree.c
index 1aee09811..e988aed6a 100644
--- a/tree.c
+++ b/tree.c
@@ -5,6 +5,71 @@
 
 const char *tree_type = "tree";
 
+static int read_one_entry(unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
+{
+	int len = strlen(pathname);
+	unsigned int size = cache_entry_size(baselen + len);
+	struct cache_entry *ce = malloc(size);
+
+	memset(ce, 0, size);
+
+	ce->ce_mode = create_ce_mode(mode);
+	ce->ce_flags = create_ce_flags(baselen + len, stage);
+	memcpy(ce->name, base, baselen);
+	memcpy(ce->name + baselen, pathname, len+1);
+	memcpy(ce->sha1, sha1, 20);
+	return add_cache_entry(ce, 1);
+}
+
+static int read_tree_recursive(void *buffer, unsigned long size,
+			       const char *base, int baselen, int stage)
+{
+	while (size) {
+		int len = strlen(buffer)+1;
+		unsigned char *sha1 = buffer + len;
+		char *path = strchr(buffer, ' ')+1;
+		unsigned int mode;
+
+		if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
+			return -1;
+
+		buffer = sha1 + 20;
+		size -= len + 20;
+
+		if (S_ISDIR(mode)) {
+			int retval;
+			int pathlen = strlen(path);
+			char *newbase = malloc(baselen + 1 + pathlen);
+			void *eltbuf;
+			char elttype[20];
+			unsigned long eltsize;
+
+			eltbuf = read_sha1_file(sha1, elttype, &eltsize);
+			if (!eltbuf || strcmp(elttype, "tree"))
+				return -1;
+			memcpy(newbase, base, baselen);
+			memcpy(newbase + baselen, path, pathlen);
+			newbase[baselen + pathlen] = '/';
+			retval = read_tree_recursive(eltbuf, eltsize,
+						     newbase,
+						     baselen + pathlen + 1, stage);
+			free(eltbuf);
+			free(newbase);
+			if (retval)
+				return -1;
+			continue;
+		}
+		if (read_one_entry(sha1, base, baselen, path, mode, stage) < 0)
+			return -1;
+	}
+	return 0;
+}
+
+int read_tree(void *buffer, unsigned long size, int stage)
+{
+	return read_tree_recursive(buffer, size, "", 0, stage);
+}
+
 struct tree *lookup_tree(unsigned char *sha1)
 {
 	struct object *obj = lookup_object(sha1);