convert object type handling from a string to a number
[git/git.git] / sha1_file.c
index 423ff0a..3831614 100644 (file)
@@ -983,26 +983,27 @@ static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size
  * too permissive for what we want to check. So do an anal
  * object header parse by hand.
  */
-static int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
+static int parse_sha1_header(const char *hdr, unsigned long *sizep)
 {
+       char type[10];
        int i;
        unsigned long size;
 
        /*
         * The type can be at most ten bytes (including the 
         * terminating '\0' that we add), and is followed by
-        * a space. 
+        * a space.
         */
-       i = 10;
+       i = 0;
        for (;;) {
                char c = *hdr++;
                if (c == ' ')
                        break;
-               if (!--i)
+               type[i++] = c;
+               if (i >= sizeof(type))
                        return -1;
-               *type++ = c;
        }
-       *type = 0;
+       type[i] = 0;
 
        /*
         * The length must follow immediately, and be in canonical
@@ -1025,17 +1026,17 @@ static int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
        /*
         * The length must be followed by a zero byte
         */
-       return *hdr ? -1 : 0;
+       return *hdr ? -1 : type_from_string(type);
 }
 
-void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
+void * unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size)
 {
        int ret;
        z_stream stream;
        char hdr[8192];
 
        ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
-       if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
+       if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
                return NULL;
 
        return unpack_sha1_rest(&stream, hdr, *size);
@@ -1044,7 +1045,7 @@ void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned l
 static unsigned long get_delta_base(struct packed_git *p,
                                    struct pack_window **w_curs,
                                    unsigned long *curpos,
-                                   enum object_type kind,
+                                   enum object_type type,
                                    unsigned long delta_obj_offset)
 {
        unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
@@ -1056,7 +1057,7 @@ static unsigned long get_delta_base(struct packed_git *p,
         * that is assured.  An OFS_DELTA longer than the hash size
         * is stupid, as then a REF_DELTA would be smaller to store.
         */
-       if (kind == OBJ_OFS_DELTA) {
+       if (type == OBJ_OFS_DELTA) {
                unsigned used = 0;
                unsigned char c = base_info[used++];
                base_offset = c & 127;
@@ -1071,7 +1072,7 @@ static unsigned long get_delta_base(struct packed_git *p,
                if (base_offset >= delta_obj_offset)
                        die("delta base offset out of bound");
                *curpos += used;
-       } else if (kind == OBJ_REF_DELTA) {
+       } else if (type == OBJ_REF_DELTA) {
                /* The base entry _must_ be in the same pack */
                base_offset = find_pack_entry_one(base_info, p);
                if (!base_offset)
@@ -1085,28 +1086,25 @@ static unsigned long get_delta_base(struct packed_git *p,
 
 /* forward declaration for a mutually recursive function */
 static int packed_object_info(struct packed_git *p, unsigned long offset,
-                             char *type, unsigned long *sizep);
+                             unsigned long *sizep);
 
 static int packed_delta_info(struct packed_git *p,
                             struct pack_window **w_curs,
                             unsigned long curpos,
-                            enum object_type kind,
+                            enum object_type type,
                             unsigned long obj_offset,
-                            char *type,
                             unsigned long *sizep)
 {
        unsigned long base_offset;
 
-       base_offset = get_delta_base(p, w_curs, &curpos, kind, obj_offset);
+       base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
+       type = packed_object_info(p, base_offset, NULL);
 
        /* We choose to only get the type of the base object and
         * ignore potentially corrupt pack file that expects the delta
         * based on a base with a wrong size.  This saves tons of
         * inflate() calls.
         */
-       if (packed_object_info(p, base_offset, type, NULL))
-               die("cannot get info for delta-pack base");
-
        if (sizep) {
                const unsigned char *data;
                unsigned char delta_head[20], *in;
@@ -1141,7 +1139,8 @@ static int packed_delta_info(struct packed_git *p,
                /* Read the result size */
                *sizep = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
        }
-       return 0;
+
+       return type;
 }
 
 static int unpack_object_header(struct packed_git *p,
@@ -1169,38 +1168,36 @@ static int unpack_object_header(struct packed_git *p,
        return type;
 }
 
-void packed_object_info_detail(struct packed_git *p,
-                              unsigned long obj_offset,
-                              char *type,
-                              unsigned long *size,
-                              unsigned long *store_size,
-                              unsigned int *delta_chain_length,
-                              unsigned char *base_sha1)
+const char *packed_object_info_detail(struct packed_git *p,
+                                     unsigned long obj_offset,
+                                     unsigned long *size,
+                                     unsigned long *store_size,
+                                     unsigned int *delta_chain_length,
+                                     unsigned char *base_sha1)
 {
        struct pack_window *w_curs = NULL;
        unsigned long curpos, dummy;
        unsigned char *next_sha1;
-       enum object_type kind;
+       enum object_type type;
 
        *delta_chain_length = 0;
        curpos = obj_offset;
-       kind = unpack_object_header(p, &w_curs, &curpos, size);
+       type = unpack_object_header(p, &w_curs, &curpos, size);
 
        for (;;) {
-               switch (kind) {
+               switch (type) {
                default:
                        die("pack %s contains unknown object type %d",
-                           p->pack_name, kind);
+                           p->pack_name, type);
                case OBJ_COMMIT:
                case OBJ_TREE:
                case OBJ_BLOB:
                case OBJ_TAG:
-                       strcpy(type, typename(kind));
                        *store_size = 0; /* notyet */
                        unuse_pack(&w_curs);
-                       return;
+                       return typename(type);
                case OBJ_OFS_DELTA:
-                       obj_offset = get_delta_base(p, &w_curs, &curpos, kind, obj_offset);
+                       obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
                        if (*delta_chain_length == 0) {
                                /* TODO: find base_sha1 as pointed by curpos */
                        }
@@ -1214,39 +1211,38 @@ void packed_object_info_detail(struct packed_git *p,
                }
                (*delta_chain_length)++;
                curpos = obj_offset;
-               kind = unpack_object_header(p, &w_curs, &curpos, &dummy);
+               type = unpack_object_header(p, &w_curs, &curpos, &dummy);
        }
 }
 
 static int packed_object_info(struct packed_git *p, unsigned long obj_offset,
-                             char *type, unsigned long *sizep)
+                             unsigned long *sizep)
 {
        struct pack_window *w_curs = NULL;
        unsigned long size, curpos = obj_offset;
-       enum object_type kind;
+       enum object_type type;
 
-       kind = unpack_object_header(p, &w_curs, &curpos, &size);
+       type = unpack_object_header(p, &w_curs, &curpos, &size);
 
-       switch (kind) {
+       switch (type) {
        case OBJ_OFS_DELTA:
        case OBJ_REF_DELTA:
-               packed_delta_info(p, &w_curs, curpos, kind,
-                                 obj_offset, type, sizep);
+               type = packed_delta_info(p, &w_curs, curpos,
+                                        type, obj_offset, sizep);
                break;
        case OBJ_COMMIT:
        case OBJ_TREE:
        case OBJ_BLOB:
        case OBJ_TAG:
-               strcpy(type, typename(kind));
                if (sizep)
                        *sizep = size;
                break;
        default:
                die("pack %s contains unknown object type %d",
-                   p->pack_name, kind);
+                   p->pack_name, type);
        }
        unuse_pack(&w_curs);
-       return 0;
+       return type;
 }
 
 static void *unpack_compressed_entry(struct packed_git *p,
@@ -1284,15 +1280,14 @@ static void *unpack_delta_entry(struct packed_git *p,
                                struct pack_window **w_curs,
                                unsigned long curpos,
                                unsigned long delta_size,
-                               enum object_type kind,
                                unsigned long obj_offset,
-                               char *type,
+                               enum object_type *type,
                                unsigned long *sizep)
 {
        void *delta_data, *result, *base;
-       unsigned long result_size, base_size, base_offset;
+       unsigned long base_size, base_offset;
 
-       base_offset = get_delta_base(p, w_curs, &curpos, kind, obj_offset);
+       base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
        base = unpack_entry(p, base_offset, type, &base_size);
        if (!base)
                die("failed to read delta base object at %lu from %s",
@@ -1301,43 +1296,39 @@ static void *unpack_delta_entry(struct packed_git *p,
        delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
        result = patch_delta(base, base_size,
                             delta_data, delta_size,
-                            &result_size);
+                            sizep);
        if (!result)
                die("failed to apply delta");
        free(delta_data);
        free(base);
-       *sizep = result_size;
        return result;
 }
 
 void *unpack_entry(struct packed_git *p, unsigned long obj_offset,
-                  char *type, unsigned long *sizep)
+                  enum object_type *type, unsigned long *sizep)
 {
        struct pack_window *w_curs = NULL;
-       unsigned long size, curpos = obj_offset;
-       enum object_type kind;
-       void *retval;
+       unsigned long curpos = obj_offset;
+       void *data;
 
-       kind = unpack_object_header(p, &w_curs, &curpos, &size);
-       switch (kind) {
+       *type = unpack_object_header(p, &w_curs, &curpos, sizep);
+       switch (*type) {
        case OBJ_OFS_DELTA:
        case OBJ_REF_DELTA:
-               retval = unpack_delta_entry(p, &w_curs, curpos, size,
-                       kind, obj_offset, type, sizep);
+               data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
+                                         obj_offset, type, sizep);
                break;
        case OBJ_COMMIT:
        case OBJ_TREE:
        case OBJ_BLOB:
        case OBJ_TAG:
-               strcpy(type, typename(kind));
-               *sizep = size;
-               retval = unpack_compressed_entry(p, &w_curs, curpos, size);
+               data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
                break;
        default:
-               die("unknown object type %i in %s", kind, p->pack_name);
+               die("unknown object type %i in %s", *type, p->pack_name);
        }
        unuse_pack(&w_curs);
-       return retval;
+       return data;
 }
 
 int num_packed_objects(const struct packed_git *p)
@@ -1444,10 +1435,10 @@ struct packed_git *find_sha1_pack(const unsigned char *sha1,
                        return p;
        }
        return NULL;
-       
+
 }
 
-static int sha1_loose_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
+static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
 {
        int status;
        unsigned long mapsize, size;
@@ -1461,31 +1452,29 @@ static int sha1_loose_object_info(const unsigned char *sha1, char *type, unsigne
        if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
                status = error("unable to unpack %s header",
                               sha1_to_hex(sha1));
-       else if (parse_sha1_header(hdr, type, &size) < 0)
+       else if ((status = parse_sha1_header(hdr, &size)) < 0)
                status = error("unable to parse %s header", sha1_to_hex(sha1));
-       else {
-               status = 0;
-               if (sizep)
-                       *sizep = size;
-       }
+       else if (sizep)
+               *sizep = size;
        inflateEnd(&stream);
        munmap(map, mapsize);
        return status;
 }
 
-int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
+int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
 {
        struct pack_entry e;
 
        if (!find_pack_entry(sha1, &e, NULL)) {
                reprepare_packed_git();
                if (!find_pack_entry(sha1, &e, NULL))
-                       return sha1_loose_object_info(sha1, type, sizep);
+                       return sha1_loose_object_info(sha1, sizep);
        }
-       return packed_object_info(e.p, e.offset, type, sizep);
+       return packed_object_info(e.p, e.offset, sizep);
 }
 
-static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
+static void *read_packed_sha1(const unsigned char *sha1,
+                             enum object_type *type, unsigned long *size)
 {
        struct pack_entry e;
 
@@ -1503,7 +1492,7 @@ static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned lo
  */
 static struct cached_object {
        unsigned char sha1[20];
-       const char *type;
+       enum object_type type;
        void *buf;
        unsigned long size;
 } *cached_objects;
@@ -1521,11 +1510,12 @@ static struct cached_object *find_cached_object(const unsigned char *sha1)
        return NULL;
 }
 
-int pretend_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *sha1)
+int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
+                     unsigned char *sha1)
 {
        struct cached_object *co;
 
-       hash_sha1_file(buf, len, type, sha1);
+       hash_sha1_file(buf, len, typename(type), sha1);
        if (has_sha1_file(sha1) || find_cached_object(sha1))
                return 0;
        if (cached_object_alloc <= cached_object_nr) {
@@ -1536,14 +1526,15 @@ int pretend_sha1_file(void *buf, unsigned long len, const char *type, unsigned c
        }
        co = &cached_objects[cached_object_nr++];
        co->size = len;
-       co->type = strdup(type);
+       co->type = type;
        co->buf = xmalloc(len);
        memcpy(co->buf, buf, len);
        hashcpy(co->sha1, sha1);
        return 0;
 }
 
-void *read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
+void *read_sha1_file(const unsigned char *sha1, enum object_type *type,
+                    unsigned long *size)
 {
        unsigned long mapsize;
        void *map, *buf;
@@ -1554,7 +1545,7 @@ void *read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
                buf = xmalloc(co->size + 1);
                memcpy(buf, co->buf, co->size);
                ((char*)buf)[co->size] = 0;
-               strcpy(type, co->type);
+               *type = co->type;
                *size = co->size;
                return buf;
        }
@@ -1573,33 +1564,34 @@ void *read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
 }
 
 void *read_object_with_reference(const unsigned char *sha1,
-                                const char *required_type,
+                                const char *required_type_name,
                                 unsigned long *size,
                                 unsigned char *actual_sha1_return)
 {
-       char type[20];
+       enum object_type type, required_type;
        void *buffer;
        unsigned long isize;
        unsigned char actual_sha1[20];
 
+       required_type = type_from_string(required_type_name);
        hashcpy(actual_sha1, sha1);
        while (1) {
                int ref_length = -1;
                const char *ref_type = NULL;
 
-               buffer = read_sha1_file(actual_sha1, type, &isize);
+               buffer = read_sha1_file(actual_sha1, &type, &isize);
                if (!buffer)
                        return NULL;
-               if (!strcmp(type, required_type)) {
+               if (type == required_type) {
                        *size = isize;
                        if (actual_sha1_return)
                                hashcpy(actual_sha1_return, actual_sha1);
                        return buffer;
                }
                /* Handle references */
-               else if (!strcmp(type, commit_type))
+               else if (type == OBJ_COMMIT)
                        ref_type = "tree ";
-               else if (!strcmp(type, tag_type))
+               else if (type == OBJ_TAG)
                        ref_type = "object ";
                else {
                        free(buffer);
@@ -1841,17 +1833,17 @@ static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
        z_stream stream;
        unsigned char *unpacked;
        unsigned long len;
-       char type[20];
+       enum object_type type;
        char hdr[32];
        int hdrlen;
        void *buf;
 
        /* need to unpack and recompress it by itself */
-       unpacked = read_packed_sha1(sha1, type, &len);
+       unpacked = read_packed_sha1(sha1, &type, &len);
        if (!unpacked)
                error("cannot read sha1_file for %s", sha1_to_hex(sha1));
 
-       hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
+       hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
 
        /* Set it up */
        memset(&stream, 0, sizeof(stream));