object-file: extract function to read object info from path

Extract a new function that allows us to read object info for a specific
loose object via a user-supplied path. This function will be used in a
subsequent commit.

Note that this also allows us to drop `stat_loose_object()`, which is
a simple wrapper around `odb_loose_path()` plus lstat(3p).

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/object-file.c b/object-file.c
index 8fa461dd5966151575fa040da5e5c5ae52ffa014..a651129426992c93207ddf9c27c3346c48a4032e 100644 (file)
--- a/object-file.c
+++ b/object-file.c
@@ -165,30 +165,13 @@ int stream_object_signature(struct repository *r, const struct object_id *oid)
 }
 
 /*
- * Find "oid" as a loose object in given source.
- * Returns 0 on success, negative on failure.
+ * Find "oid" as a loose object in given source, open the object and return its
+ * file descriptor. Returns the file descriptor on success, negative on failure.
  *
  * The "path" out-parameter will give the path of the object we found (if any).
  * Note that it may point to static storage and is only valid until another
  * call to stat_loose_object().
  */
-static int stat_loose_object(struct odb_source_loose *loose,
-                            const struct object_id *oid,
-                            struct stat *st, const char **path)
-{
-       static struct strbuf buf = STRBUF_INIT;
-
-       *path = odb_loose_path(loose->source, &buf, oid);
-       if (!lstat(*path, st))
-               return 0;
-
-       return -1;
-}
-
-/*
- * Like stat_loose_object(), but actually open the object and return the
- * descriptor. See the caveats on the "path" parameter above.
- */
 static int open_loose_object(struct odb_source_loose *loose,
                             const struct object_id *oid, const char **path)
 {
@@ -412,7 +395,8 @@ static int parse_loose_header(const char *hdr, struct object_info *oi)
        return 0;
 }
 
-int odb_source_loose_read_object_info(struct odb_source *source,
+static int read_object_info_from_path(struct odb_source *source,
+                                     const char *path,
                                      const struct object_id *oid,
                                      struct object_info *oi,
                                      unsigned flags)
@@ -420,7 +404,6 @@ int odb_source_loose_read_object_info(struct odb_source *source,
        int ret;
        int fd;
        unsigned long mapsize;
-       const char *path;
        void *map = NULL;
        git_zstream stream, *stream_to_end = NULL;
        char hdr[MAX_HEADER_LEN];
@@ -443,7 +426,7 @@ int odb_source_loose_read_object_info(struct odb_source *source,
                        goto out;
                }
 
-               if (stat_loose_object(source->loose, oid, &st, &path) < 0) {
+               if (lstat(path, &st) < 0) {
                        ret = -1;
                        goto out;
                }
@@ -455,7 +438,7 @@ int odb_source_loose_read_object_info(struct odb_source *source,
                goto out;
        }
 
-       fd = open_loose_object(source->loose, oid, &path);
+       fd = git_open(path);
        if (fd < 0) {
                if (errno != ENOENT)
                        error_errno(_("unable to open loose object %s"), oid_to_hex(oid));
@@ -534,6 +517,16 @@ out:
        return ret;
 }
 
+int odb_source_loose_read_object_info(struct odb_source *source,
+                                     const struct object_id *oid,
+                                     struct object_info *oi,
+                                     unsigned flags)
+{
+       static struct strbuf buf = STRBUF_INIT;
+       odb_loose_path(source, &buf, oid);
+       return read_object_info_from_path(source, buf.buf, oid, oi, flags);
+}
+
 static void hash_object_body(const struct git_hash_algo *algo, struct git_hash_ctx *c,
                             const void *buf, unsigned long len,
                             struct object_id *oid,