pack-objects: small cleanup

diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index f504cff7566159332c89f830a871da0ea05868fe..8691c99518124420edd1c6ab5ddf70fb0413e37d 100644 (file)
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -102,21 +102,24 @@ static uint32_t written, written_delta;
 static uint32_t reused, reused_delta;
 
 
-static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
+static void *get_delta(struct object_entry *entry)
 {
-       unsigned long othersize, delta_size;
+       unsigned long size, base_size, delta_size;
+       void *buf, *base_buf, *delta_buf;
        enum object_type type;
-       void *otherbuf = read_sha1_file(entry->delta->idx.sha1, &type, &othersize);
-       void *delta_buf;
 
-       if (!otherbuf)
+       buf = read_sha1_file(entry->idx.sha1, &type, &size);
+       if (!buf)
+               die("unable to read %s", sha1_to_hex(entry->idx.sha1));
+       base_buf = read_sha1_file(entry->delta->idx.sha1, &type, &base_size);
+       if (!base_buf)
                die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
-        delta_buf = diff_delta(otherbuf, othersize,
+       delta_buf = diff_delta(base_buf, base_size,
                               buf, size, &delta_size, 0);
-        if (!delta_buf || delta_size != entry->delta_size)
+       if (!delta_buf || delta_size != entry->delta_size)
                die("delta size changed");
-        free(buf);
-        free(otherbuf);
+       free(buf);
+       free(base_buf);
        return delta_buf;
 }
 
@@ -223,7 +226,6 @@ static unsigned long write_object(struct sha1file *f,
                                  off_t write_offset)
 {
        unsigned long size;
-       enum object_type type;
        void *buf;
        unsigned char header[10];
        unsigned char dheader[10];
@@ -281,10 +283,7 @@ static unsigned long write_object(struct sha1file *f,
                        obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
                } else {
-                       buf = read_sha1_file(entry->idx.sha1, &type, &size);
-                       if (!buf)
-                               die("unable to read %s", sha1_to_hex(entry->idx.sha1));
-                       buf = delta_against(buf, size, entry);
+                       buf = get_delta(entry);
                        size = entry->delta_size;
                        obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
@@ -454,6 +453,7 @@ static void write_pack_file(void)
        struct pack_header hdr;
        int do_progress = progress >> pack_to_stdout;
        uint32_t nr_remaining = nr_result;
+       time_t last_mtime = 0;
 
        if (do_progress)
                progress_state = start_progress("Writing objects", nr_result);
@@ -504,6 +504,7 @@ static void write_pack_file(void)
 
                if (!pack_to_stdout) {
                        mode_t mode = umask(0);
+                       struct stat st;
                        char *idx_tmp_name, tmpname[PATH_MAX];
 
                        umask(mode);
@@ -511,6 +512,7 @@ static void write_pack_file(void)
 
                        idx_tmp_name = write_idx_file(NULL, written_list,
                                                      nr_written, sha1);
+
                        snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
                                 base_name, sha1_to_hex(sha1));
                        if (adjust_perm(pack_tmp_name, mode))
@@ -519,6 +521,28 @@ static void write_pack_file(void)
                        if (rename(pack_tmp_name, tmpname))
                                die("unable to rename temporary pack file: %s",
                                    strerror(errno));
+
+                       /*
+                        * Packs are runtime accessed in their mtime
+                        * order since newer packs are more likely to contain
+                        * younger objects.  So if we are creating multiple
+                        * packs then we should modify the mtime of later ones
+                        * to preserve this property.
+                        */
+                       if (stat(tmpname, &st) < 0) {
+                               warning("failed to stat %s: %s",
+                                       tmpname, strerror(errno));
+                       } else if (!last_mtime) {
+                               last_mtime = st.st_mtime;
+                       } else {
+                               struct utimbuf utb;
+                               utb.actime = st.st_atime;
+                               utb.modtime = --last_mtime;
+                               if (utime(tmpname, &utb) < 0)
+                                       warning("failed utime() on %s: %s",
+                                               tmpname, strerror(errno));
+                       }
+
                        snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
                                 base_name, sha1_to_hex(sha1));
                        if (adjust_perm(idx_tmp_name, mode))
@@ -527,6 +551,7 @@ static void write_pack_file(void)
                        if (rename(idx_tmp_name, tmpname))
                                die("unable to rename temporary index file: %s",
                                    strerror(errno));
+
                        free(idx_tmp_name);
                        free(pack_tmp_name);
                        puts(sha1_to_hex(sha1));