gitview.txt: improve asciidoc markup

diff --git a/sha1_file.c b/sha1_file.c
index 3db956dd5c96c6563a9505775570fbdfb4a8b720..066cff1fa6e8dd1485876984becdecd7bb4987b6 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -22,7 +22,7 @@
 #endif
 #endif
 
-const unsigned char null_sha1[20] = { 0, };
+const unsigned char null_sha1[20];
 
 static unsigned int sha1_file_open_flag = O_NOATIME;
 
@@ -463,6 +463,7 @@ int use_packed_git(struct packed_git *p)
                int fd;
                struct stat st;
                void *map;
+               struct pack_header *hdr;
 
                pack_mapped += p->pack_size;
                while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
@@ -482,13 +483,24 @@ int use_packed_git(struct packed_git *p)
                        die("packfile %s cannot be mapped.", p->pack_name);
                p->pack_base = map;
 
+               /* Check if we understand this pack file.  If we don't we're
+                * likely too old to handle it.
+                */
+               hdr = map;
+               if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
+                       die("packfile %s isn't actually a pack.", p->pack_name);
+               if (!pack_version_ok(hdr->hdr_version))
+                       die("packfile %s is version %i and not supported"
+                               " (try upgrading GIT to a newer version)",
+                               p->pack_name, ntohl(hdr->hdr_version));
+
                /* Check if the pack file matches with the index file.
                 * this is cheap.
                 */
-               if (memcmp((char*)(p->index_base) + p->index_size - 40,
-                          (char *) p->pack_base + p->pack_size - 20,
-                          20)) {
-
+               if (hashcmp((unsigned char *)(p->index_base) +
+                           p->index_size - 40,
+                           (unsigned char *)p->pack_base +
+                           p->pack_size - 20)) {
                        die("packfile %s does not match index.", p->pack_name);
                }
        }
@@ -643,11 +655,10 @@ int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long siz
        SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
        SHA1_Update(&c, map, size);
        SHA1_Final(real_sha1, &c);
-       return memcmp(sha1, real_sha1, 20) ? -1 : 0;
+       return hashcmp(sha1, real_sha1) ? -1 : 0;
 }
 
-static void *map_sha1_file_internal(const unsigned char *sha1,
-                                   unsigned long *size)
+void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
 {
        struct stat st;
        void *map;
@@ -684,10 +695,26 @@ static void *map_sha1_file_internal(const unsigned char *sha1,
        return map;
 }
 
+int legacy_loose_object(unsigned char *map)
+{
+       unsigned int word;
+
+       /*
+        * Is it a zlib-compressed buffer? If so, the first byte
+        * must be 0x78 (15-bit window size, deflated), and the
+        * first 16-bit word is evenly divisible by 31
+        */
+       word = (map[0] << 8) + map[1];
+       if (map[0] == 0x78 && !(word % 31))
+               return 1;
+       else
+               return 0;
+}
+
 static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
 {
        unsigned char c;
-       unsigned int word, bits;
+       unsigned int bits;
        unsigned long size;
        static const char *typename[8] = {
                NULL,   /* OBJ_EXT */
@@ -703,13 +730,7 @@ static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned lon
        stream->next_out = buffer;
        stream->avail_out = bufsiz;
 
-       /*
-        * Is it a zlib-compressed buffer? If so, the first byte
-        * must be 0x78 (15-bit window size, deflated), and the
-        * first 16-bit word is evenly divisible by 31
-        */
-       word = (map[0] << 8) + map[1];
-       if (map[0] == 0x78 && !(word % 31)) {
+       if (legacy_loose_object(map)) {
                inflateInit(stream);
                return inflate(stream, 0);
        }
@@ -932,7 +953,7 @@ int check_reuse_pack_delta(struct packed_git *p, unsigned long offset,
        ptr = unpack_object_header(p, ptr, kindp, sizep);
        if (*kindp != OBJ_DELTA)
                goto done;
-       memcpy(base, (char *) p->pack_base + ptr, 20);
+       memcpy(base, (unsigned char *) p->pack_base + ptr, 20);
        status = 0;
  done:
        unuse_packed_git(p);
@@ -1036,9 +1057,6 @@ static int packed_object_info(struct pack_entry *entry,
        return 0;
 }
 
-/* forward declaration for a mutually recursive function */
-static void *unpack_entry(struct pack_entry *, char *, unsigned long *);
-
 static void *unpack_delta_entry(unsigned char *base_sha1,
                                unsigned long delta_size,
                                unsigned long left,
@@ -1197,7 +1215,7 @@ int find_pack_entry_one(const unsigned char *sha1,
 
        do {
                int mi = (lo + hi) / 2;
-               int cmp = memcmp((char *) index + (24 * mi) + 4, sha1, 20);
+               int cmp = hashcmp((unsigned char *)index + (24 * mi) + 4, sha1);
                if (!cmp) {
                        e->offset = ntohl(*((unsigned int *) ((char *) index + (24 * mi))));
                        memcpy(e->sha1, sha1, 20);
@@ -1246,7 +1264,7 @@ int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep
        z_stream stream;
        char hdr[128];
 
-       map = map_sha1_file_internal(sha1, &mapsize);
+       map = map_sha1_file(sha1, &mapsize);
        if (!map) {
                struct pack_entry e;
 
@@ -1291,7 +1309,7 @@ void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size
 
        if (find_pack_entry(sha1, &e))
                return read_packed_sha1(sha1, type, size);
-       map = map_sha1_file_internal(sha1, &mapsize);
+       map = map_sha1_file(sha1, &mapsize);
        if (map) {
                buf = unpack_sha1_file(map, mapsize, type, size);
                munmap(map, mapsize);
@@ -1629,7 +1647,7 @@ int write_sha1_to_fd(int fd, const unsigned char *sha1)
 {
        int retval;
        unsigned long objsize;
-       void *buf = map_sha1_file_internal(sha1, &objsize);
+       void *buf = map_sha1_file(sha1, &objsize);
 
        if (buf) {
                retval = write_buffer(fd, buf, objsize);
@@ -1706,7 +1724,7 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
                unlink(tmpfile);
                return error("File %s corrupted", sha1_to_hex(sha1));
        }
-       if (memcmp(sha1, real_sha1, 20)) {
+       if (hashcmp(sha1, real_sha1)) {
                unlink(tmpfile);
                return error("File %s has bad hash", sha1_to_hex(sha1));
        }