[PATCH] Update git-clone documentation

[git.git] / sha1_file.c

diff --git a/sha1_file.c b/sha1_file.c
index 2d109f9..895c1fa 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -20,6 +20,8 @@
 #endif
 #endif
 
+const unsigned char null_sha1[20] = { 0, };
+
 static unsigned int sha1_file_open_flag = O_NOATIME;
 
 static unsigned hexval(char c)
@@ -50,26 +52,33 @@ static char *git_dir, *git_object_dir, *git_index_file, *git_refs_dir,
        *git_graft_file;
 static void setup_git_env(void)
 {
-       git_dir = gitenv(GIT_DIR_ENVIRONMENT);
+       git_dir = getenv(GIT_DIR_ENVIRONMENT);
        if (!git_dir)
                git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
-       git_object_dir = gitenv(DB_ENVIRONMENT);
+       git_object_dir = getenv(DB_ENVIRONMENT);
        if (!git_object_dir) {
                git_object_dir = xmalloc(strlen(git_dir) + 9);
                sprintf(git_object_dir, "%s/objects", git_dir);
        }
        git_refs_dir = xmalloc(strlen(git_dir) + 6);
        sprintf(git_refs_dir, "%s/refs", git_dir);
-       git_index_file = gitenv(INDEX_ENVIRONMENT);
+       git_index_file = getenv(INDEX_ENVIRONMENT);
        if (!git_index_file) {
                git_index_file = xmalloc(strlen(git_dir) + 7);
                sprintf(git_index_file, "%s/index", git_dir);
        }
-       git_graft_file = gitenv(GRAFT_ENVIRONMENT);
+       git_graft_file = getenv(GRAFT_ENVIRONMENT);
        if (!git_graft_file)
                git_graft_file = strdup(git_path("info/grafts"));
 }
 
+char *get_git_dir(void)
+{
+       if (!git_dir)
+               setup_git_env();
+       return git_dir;
+}
+
 char *get_object_directory(void)
 {
        if (!git_object_dir)
@@ -240,50 +249,75 @@ static struct alternate_object_database **alt_odb_tail;
  * SHA1, an extra slash for the first level indirection, and the
  * terminating NUL.
  */
-static void link_alt_odb_entries(const char *alt, const char *ep)
+static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
+                                const char *relative_base)
 {
        const char *cp, *last;
        struct alternate_object_database *ent;
+       int base_len = -1;
 
        last = alt;
-       do {
-               for (cp = last; cp < ep && *cp != ':'; cp++)
+       while (last < ep) {
+               cp = last;
+               if (cp < ep && *cp == '#') {
+                       while (cp < ep && *cp != sep)
+                               cp++;
+                       last = cp + 1;
+                       continue;
+               }
+               for ( ; cp < ep && *cp != sep; cp++)
                        ;
                if (last != cp) {
                        /* 43 = 40-byte + 2 '/' + terminating NUL */
                        int pfxlen = cp - last;
                        int entlen = pfxlen + 43;
 
+                       if (*last != '/' && relative_base) {
+                               /* Relative alt-odb */
+                               if (base_len < 0)
+                                       base_len = strlen(relative_base) + 1;
+                               entlen += base_len;
+                               pfxlen += base_len;
+                       }
                        ent = xmalloc(sizeof(*ent) + entlen);
                        *alt_odb_tail = ent;
                        alt_odb_tail = &(ent->next);
                        ent->next = NULL;
-
-                       memcpy(ent->base, last, pfxlen);
+                       if (*last != '/' && relative_base) {
+                               memcpy(ent->base, relative_base, base_len - 1);
+                               ent->base[base_len - 1] = '/';
+                               memcpy(ent->base + base_len,
+                                      last, cp - last);
+                       }
+                       else
+                               memcpy(ent->base, last, pfxlen);
                        ent->name = ent->base + pfxlen + 1;
                        ent->base[pfxlen] = ent->base[pfxlen + 3] = '/';
                        ent->base[entlen-1] = 0;
                }
-               while (cp < ep && *cp == ':')
+               while (cp < ep && *cp == sep)
                        cp++;
                last = cp;
-       } while (cp < ep);
+       }
 }
 
 void prepare_alt_odb(void)
 {
        char path[PATH_MAX];
-       char *map, *ep;
+       char *map;
        int fd;
        struct stat st;
-       char *alt = gitenv(ALTERNATE_DB_ENVIRONMENT) ? : "";
+       char *alt;
+
+       alt = getenv(ALTERNATE_DB_ENVIRONMENT);
+       if (!alt) alt = "";
 
-       sprintf(path, "%s/info/alternates", get_object_directory());
        if (alt_odb_tail)
                return;
        alt_odb_tail = &alt_odb_list;
-       link_alt_odb_entries(alt, alt + strlen(alt));
+       link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL);
 
+       sprintf(path, "%s/info/alternates", get_object_directory());
        fd = open(path, O_RDONLY);
        if (fd < 0)
                return;
@@ -296,10 +330,8 @@ void prepare_alt_odb(void)
        if (map == MAP_FAILED)
                return;
 
-       /* Remove the trailing newline */
-       for (ep = map + st.st_size - 1; map < ep && ep[-1] == '\n'; ep--)
-               ;
-       link_alt_odb_entries(map, ep);
+       link_alt_odb_entries(map, map + st.st_size, '\n',
+                            get_object_directory());
        munmap(map, st.st_size);
 }
 
@@ -476,12 +508,18 @@ struct packed_git *add_packed_git(char *path, int path_len)
 
 struct packed_git *parse_pack_index(unsigned char *sha1)
 {
+       char *path = sha1_pack_index_name(sha1);
+       return parse_pack_index_file(sha1, path);
+}
+
+struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
+{
        struct packed_git *p;
        unsigned long idx_size;
        void *idx_map;
-       char *path = sha1_pack_index_name(sha1);
+       char *path;
 
-       if (check_packed_git_idx(path, &idx_size, &idx_map))
+       if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
                return NULL;
 
        path = sha1_pack_name(sha1);
@@ -835,7 +873,8 @@ void packed_object_info_detail(struct pack_entry *e,
                strcpy(type, "tag");
                break;
        default:
-               die("corrupted pack file");
+               die("corrupted pack file %s containing object of kind %d",
+                   p->pack_name, kind);
        }
        *store_size = 0; /* notyet */
 }
@@ -874,7 +913,8 @@ static int packed_object_info(struct pack_entry *entry,
                strcpy(type, "tag");
                break;
        default:
-               die("corrupted pack file");
+               die("corrupted pack file %s containing object of kind %d",
+                   p->pack_name, kind);
        }
        if (sizep)
                *sizep = size;
@@ -974,7 +1014,7 @@ static void *unpack_entry(struct pack_entry *entry,
        retval = unpack_entry_gently(entry, type, sizep);
        unuse_packed_git(p);
        if (!retval)
-               die("corrupted pack file");
+               die("corrupted pack file %s", p->pack_name);
        return retval;
 }