[PATCH] write_sha1_to_fd()
[git/git.git] / sha1_file.c
index 3178fbf..b13578b 100644 (file)
@@ -102,9 +102,27 @@ char *get_index_file(void)
        return git_index_file;
 }
 
+int safe_create_leading_directories(char *path)
+{
+       char *pos = path;
+
+       while (pos) {
+               pos = strchr(pos, '/');
+               if (!pos)
+                       break;
+               *pos = 0;
+               if (mkdir(path, 0777) < 0)
+                       if (errno != EEXIST) {
+                               *pos = '/';
+                               return -1;
+                       }
+               *pos++ = '/';
+       }
+       return 0;
+}
+
 int get_sha1(const char *str, unsigned char *sha1)
 {
-       static char pathname[PATH_MAX];
        static const char *prefix[] = {
                "",
                "refs",
@@ -118,11 +136,8 @@ int get_sha1(const char *str, unsigned char *sha1)
        if (!get_sha1_hex(str, sha1))
                return 0;
 
-       if (!git_dir)
-               setup_git_env();
        for (p = prefix; *p; p++) {
-               snprintf(pathname, sizeof(pathname), "%s/%s/%s",
-                        git_dir, *p, str);
+               char * pathname = git_path("%s/%s", *p, str);
                if (!get_sha1_file(pathname, sha1))
                        return 0;
        }
@@ -272,12 +287,6 @@ static int pack_used_ctr;
 static unsigned long pack_mapped;
 struct packed_git *packed_git;
 
-struct pack_entry {
-       unsigned int offset;
-       unsigned char sha1[20];
-       struct packed_git *p;
-};
-
 static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
                                void **idx_map_)
 {
@@ -300,6 +309,8 @@ static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
                return -1;
 
        index = idx_map;
+       *idx_map_ = idx_map;
+       *idx_size_ = idx_size;
 
        /* check index map */
        if (idx_size < 4*256 + 20 + 20)
@@ -322,8 +333,6 @@ static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
        if (idx_size != 4*256 + nr * 24 + 20 + 20)
                return error("wrong index file size");
 
-       *idx_map_ = idx_map;
-       *idx_size_ = idx_size;
        return 0;
 }
 
@@ -445,6 +454,7 @@ static void prepare_packed_git_one(char *objdir)
                p->next = packed_git;
                packed_git = p;
        }
+       closedir(dir);
 }
 
 void prepare_packed_git(void)
@@ -537,7 +547,7 @@ int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void
        return inflate(stream, 0);
 }
 
-void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
+static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
 {
        int bytes = strlen(buffer) + 1;
        unsigned char *buf = xmalloc(1+size);
@@ -618,22 +628,34 @@ void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned l
        return unpack_sha1_rest(&stream, hdr, *size);
 }
 
+/* forward declaration for a mutually recursive function */
+static int packed_object_info(struct pack_entry *entry,
+                             char *type, unsigned long *sizep);
+
 static int packed_delta_info(unsigned char *base_sha1,
                             unsigned long delta_size,
                             unsigned long left,
                             char *type,
-                            unsigned long *sizep)
+                            unsigned long *sizep,
+                            struct packed_git *p)
 {
+       struct pack_entry base_ent;
+
        if (left < 20)
                die("truncated pack file");
 
+       /* The base entry _must_ be in the same pack */
+       if (!find_pack_entry_one(base_sha1, &base_ent, p))
+               die("failed to find delta-pack base object %s",
+                   sha1_to_hex(base_sha1));
+
        /* 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 (sha1_object_info(base_sha1, type, NULL))
+       if (packed_object_info(&base_ent, type, NULL))
                die("cannot get info for delta-pack base");
 
        if (sizep) {
@@ -698,6 +720,57 @@ static unsigned long unpack_object_header(struct packed_git *p, unsigned long of
        return offset;
 }
 
+void packed_object_info_detail(struct pack_entry *e,
+                              char *type,
+                              unsigned long *size,
+                              unsigned long *store_size,
+                              int *delta_chain_length,
+                              unsigned char *base_sha1)
+{
+       struct packed_git *p = e->p;
+       unsigned long offset, left;
+       unsigned char *pack;
+       enum object_type kind;
+
+       offset = unpack_object_header(p, e->offset, &kind, size);
+       pack = p->pack_base + offset;
+       left = p->pack_size - offset;
+       if (kind != OBJ_DELTA)
+               *delta_chain_length = 0;
+       else {
+               int chain_length = 0;
+               memcpy(base_sha1, pack, 20);
+               do {
+                       struct pack_entry base_ent;
+                       unsigned long junk;
+
+                       find_pack_entry_one(pack, &base_ent, p);
+                       offset = unpack_object_header(p, base_ent.offset,
+                                                     &kind, &junk);
+                       pack = p->pack_base + offset;
+                       chain_length++;
+               } while (kind == OBJ_DELTA);
+               *delta_chain_length = chain_length;
+       }
+       switch (kind) {
+       case OBJ_COMMIT:
+               strcpy(type, "commit");
+               break;
+       case OBJ_TREE:
+               strcpy(type, "tree");
+               break;
+       case OBJ_BLOB:
+               strcpy(type, "blob");
+               break;
+       case OBJ_TAG:
+               strcpy(type, "tag");
+               break;
+       default:
+               die("corrupted pack file");
+       }
+       *store_size = 0; /* notyet */
+}
+
 static int packed_object_info(struct pack_entry *entry,
                              char *type, unsigned long *sizep)
 {
@@ -716,7 +789,7 @@ static int packed_object_info(struct pack_entry *entry,
 
        switch (kind) {
        case OBJ_DELTA:
-               retval = packed_delta_info(pack, size, left, type, sizep);
+               retval = packed_delta_info(pack, size, left, type, sizep, p);
                unuse_packed_git(p);
                return retval;
        case OBJ_COMMIT:
@@ -747,8 +820,10 @@ static void *unpack_delta_entry(unsigned char *base_sha1,
                                unsigned long delta_size,
                                unsigned long left,
                                char *type,
-                               unsigned long *sizep)
+                               unsigned long *sizep,
+                               struct packed_git *p)
 {
+       struct pack_entry base_ent;
        void *data, *delta_data, *result, *base;
        unsigned long data_size, result_size, base_size;
        z_stream stream;
@@ -773,8 +848,11 @@ static void *unpack_delta_entry(unsigned char *base_sha1,
        if ((st != Z_STREAM_END) || stream.total_out != delta_size)
                die("delta data unpack failed");
 
-       /* This may recursively unpack the base, which is what we want */
-       base = read_sha1_file(base_sha1, type, &base_size);
+       /* The base entry _must_ be in the same pack */
+       if (!find_pack_entry_one(base_sha1, &base_ent, p))
+               die("failed to find delta-pack base object %s",
+                   sha1_to_hex(base_sha1));
+       base = unpack_entry_gently(&base_ent, type, &base_size);
        if (!base)
                die("failed to read delta-pack base object %s",
                    sha1_to_hex(base_sha1));
@@ -795,7 +873,7 @@ static void *unpack_non_delta_entry(unsigned char *data,
 {
        int st;
        z_stream stream;
-       char *buffer;
+       unsigned char *buffer;
 
        buffer = xmalloc(size + 1);
        buffer[size] = 0;
@@ -820,21 +898,33 @@ static void *unpack_entry(struct pack_entry *entry,
                          char *type, unsigned long *sizep)
 {
        struct packed_git *p = entry->p;
-       unsigned long offset, size, left;
-       unsigned char *pack;
-       enum object_type kind;
        void *retval;
 
        if (use_packed_git(p))
                die("cannot map packed file");
+       retval = unpack_entry_gently(entry, type, sizep);
+       unuse_packed_git(p);
+       if (!retval)
+               die("corrupted pack file");
+       return retval;
+}
+
+/* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
+void *unpack_entry_gently(struct pack_entry *entry,
+                         char *type, unsigned long *sizep)
+{
+       struct packed_git *p = entry->p;
+       unsigned long offset, size, left;
+       unsigned char *pack;
+       enum object_type kind;
+       void *retval;
 
        offset = unpack_object_header(p, entry->offset, &kind, &size);
        pack = p->pack_base + offset;
        left = p->pack_size - offset;
        switch (kind) {
        case OBJ_DELTA:
-               retval = unpack_delta_entry(pack, size, left, type, sizep);
-               unuse_packed_git(p);
+               retval = unpack_delta_entry(pack, size, left, type, sizep, p);
                return retval;
        case OBJ_COMMIT:
                strcpy(type, "commit");
@@ -849,11 +939,10 @@ static void *unpack_entry(struct pack_entry *entry,
                strcpy(type, "tag");
                break;
        default:
-               die("corrupted pack file");
+               return NULL;
        }
        *sizep = size;
        retval = unpack_non_delta_entry(pack, size, left);
-       unuse_packed_git(p);
        return retval;
 }
 
@@ -873,10 +962,10 @@ int nth_packed_object_sha1(const struct packed_git *p, int n,
        return 0;
 }
 
-static int find_pack_entry_1(const unsigned char *sha1,
-                            struct pack_entry *e, struct packed_git *p)
+int find_pack_entry_one(const unsigned char *sha1,
+                       struct pack_entry *e, struct packed_git *p)
 {
-       int *level1_ofs = p->index_base;
+       unsigned int *level1_ofs = p->index_base;
        int hi = ntohl(level1_ofs[*sha1]);
        int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
        void *index = p->index_base + 256;
@@ -904,7 +993,7 @@ static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
        prepare_packed_git();
 
        for (p = packed_git; p; p = p->next) {
-               if (find_pack_entry_1(sha1, e, p))
+               if (find_pack_entry_one(sha1, e, p))
                        return 1;
        }
        return 0;
@@ -1011,12 +1100,12 @@ void *read_object_with_reference(const unsigned char *sha1,
        }
 }
 
-static char *write_sha1_file_prepare(void *buf,
-                                    unsigned long len,
-                                    const char *type,
-                                    unsigned char *sha1,
-                                    unsigned char *hdr,
-                                    int *hdrlen)
+char *write_sha1_file_prepare(void *buf,
+                             unsigned long len,
+                             const char *type,
+                             unsigned char *sha1,
+                             unsigned char *hdr,
+                             int *hdrlen)
 {
        SHA_CTX c;
 
@@ -1132,6 +1221,65 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha
        return 0;
 }
 
+int write_sha1_to_fd(int fd, const unsigned char *sha1)
+{
+       ssize_t size;
+       unsigned long objsize;
+       int posn = 0;
+       char *buf = map_sha1_file_internal(sha1, &objsize, 0);
+       z_stream stream;
+       if (!buf) {
+               unsigned char *unpacked;
+               unsigned long len;
+               char type[20];
+               char hdr[50];
+               int hdrlen;
+               // need to unpack and recompress it by itself
+               unpacked = read_packed_sha1(sha1, type, &len);
+
+               hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
+
+               /* Set it up */
+               memset(&stream, 0, sizeof(stream));
+               deflateInit(&stream, Z_BEST_COMPRESSION);
+               size = deflateBound(&stream, len + hdrlen);
+               buf = xmalloc(size);
+
+               /* Compress it */
+               stream.next_out = buf;
+               stream.avail_out = size;
+               
+               /* First header.. */
+               stream.next_in = hdr;
+               stream.avail_in = hdrlen;
+               while (deflate(&stream, 0) == Z_OK)
+                       /* nothing */;
+
+               /* Then the data itself.. */
+               stream.next_in = unpacked;
+               stream.avail_in = len;
+               while (deflate(&stream, Z_FINISH) == Z_OK)
+                       /* nothing */;
+               deflateEnd(&stream);
+               
+               objsize = stream.total_out;
+       }
+
+       do {
+               size = write(fd, buf + posn, objsize - posn);
+               if (size <= 0) {
+                       if (!size) {
+                               fprintf(stderr, "write closed");
+                       } else {
+                               perror("write ");
+                       }
+                       return -1;
+               }
+               posn += size;
+       } while (posn < objsize);
+       return 0;
+}
+
 int write_sha1_from_fd(const unsigned char *sha1, int fd)
 {
        char *filename = sha1_file_name(sha1);
@@ -1194,6 +1342,12 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd)
        return 0;
 }
 
+int has_sha1_pack(const unsigned char *sha1)
+{
+       struct pack_entry e;
+       return find_pack_entry(sha1, &e);
+}
+
 int has_sha1_file(const unsigned char *sha1)
 {
        struct stat st;
@@ -1204,11 +1358,13 @@ int has_sha1_file(const unsigned char *sha1)
        return find_pack_entry(sha1, &e);
 }
 
-int index_fd(unsigned char *sha1, int fd, struct stat *st)
+int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
 {
        unsigned long size = st->st_size;
        void *buf;
        int ret;
+       unsigned char hdr[50];
+       int hdrlen;
 
        buf = "";
        if (size)
@@ -1217,7 +1373,14 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st)
        if ((int)(long)buf == -1)
                return -1;
 
-       ret = write_sha1_file(buf, size, "blob", sha1);
+       if (!type)
+               type = "blob";
+       if (write_object)
+               ret = write_sha1_file(buf, size, type, sha1);
+       else {
+               write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
+               ret = 0;
+       }
        if (size)
                munmap(buf, size);
        return ret;