git-rm: honor -n flag.
[git.git] / sha1_file.c
index 8d3a65f..aea0f40 100644 (file)
@@ -6,11 +6,13 @@
  * This handles basic git sha1 object files - packing, unpacking,
  * creation etc.
  */
-#include <sys/types.h>
-#include <dirent.h>
 #include "cache.h"
 #include "delta.h"
 #include "pack.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree.h"
 
 #ifndef O_NOATIME
 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
@@ -20,6 +22,8 @@
 #endif
 #endif
 
+const unsigned char null_sha1[20] = { 0, };
+
 static unsigned int sha1_file_open_flag = O_NOATIME;
 
 static unsigned hexval(char c)
@@ -46,121 +50,68 @@ int get_sha1_hex(const char *hex, unsigned char *sha1)
        return 0;
 }
 
-static int get_sha1_file(const char *path, unsigned char *result)
+int adjust_shared_perm(const char *path)
 {
-       char buffer[60];
-       int fd = open(path, O_RDONLY);
-       int len;
+       struct stat st;
+       int mode;
 
-       if (fd < 0)
-               return -1;
-       len = read(fd, buffer, sizeof(buffer));
-       close(fd);
-       if (len < 40)
+       if (!shared_repository)
+               return 0;
+       if (lstat(path, &st) < 0)
                return -1;
-       return get_sha1_hex(buffer, result);
-}
-
-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);
-       if (!git_dir)
-               git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
-       git_object_dir = gitenv(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);
-       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);
-       if (!git_graft_file)
-               git_graft_file = strdup(git_path("info/grafts"));
-}
-
-char *get_object_directory(void)
-{
-       if (!git_object_dir)
-               setup_git_env();
-       return git_object_dir;
-}
-
-char *get_refs_directory(void)
-{
-       if (!git_refs_dir)
-               setup_git_env();
-       return git_refs_dir;
-}
-
-char *get_index_file(void)
-{
-       if (!git_index_file)
-               setup_git_env();
-       return git_index_file;
-}
-
-char *get_graft_file(void)
-{
-       if (!git_graft_file)
-               setup_git_env();
-       return git_graft_file;
+       mode = st.st_mode;
+       if (mode & S_IRUSR)
+               mode |= S_IRGRP;
+       if (mode & S_IWUSR)
+               mode |= S_IWGRP;
+       if (mode & S_IXUSR)
+               mode |= S_IXGRP;
+       if (S_ISDIR(mode))
+               mode |= S_ISGID;
+       if (chmod(path, mode) < 0)
+               return -2;
+       return 0;
 }
 
 int safe_create_leading_directories(char *path)
 {
        char *pos = path;
+       struct stat st;
+
+       if (*pos == '/')
+               pos++;
 
        while (pos) {
                pos = strchr(pos, '/');
                if (!pos)
                        break;
                *pos = 0;
-               if (mkdir(path, 0777) < 0)
-                       if (errno != EEXIST) {
+               if (!stat(path, &st)) {
+                       /* path exists */
+                       if (!S_ISDIR(st.st_mode)) {
                                *pos = '/';
-                               return -1;
+                               return -3;
                        }
+               }
+               else if (mkdir(path, 0777)) {
+                       *pos = '/';
+                       return -1;
+               }
+               else if (adjust_shared_perm(path)) {
+                       *pos = '/';
+                       return -2;
+               }
                *pos++ = '/';
        }
        return 0;
 }
 
-int get_sha1(const char *str, unsigned char *sha1)
-{
-       static const char *prefix[] = {
-               "",
-               "refs",
-               "refs/tags",
-               "refs/heads",
-               "refs/snap",
-               NULL
-       };
-       const char **p;
-
-       if (!get_sha1_hex(str, sha1))
-               return 0;
-
-       for (p = prefix; *p; p++) {
-               char * pathname = git_path("%s/%s", *p, str);
-               if (!get_sha1_file(pathname, sha1))
-                       return 0;
-       }
-
-       return -1;
-}
-
 char * sha1_to_hex(const unsigned char *sha1)
 {
-       static char buffer[50];
+       static int bufno;
+       static char hexbuffer[4][50];
        static const char hex[] = "0123456789abcdef";
-       char *buf = buffer;
+       char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
        int i;
 
        for (i = 0; i < 20; i++) {
@@ -168,6 +119,8 @@ char * sha1_to_hex(const unsigned char *sha1)
                *buf++ = hex[val >> 4];
                *buf++ = hex[val & 0xf];
        }
+       *buf = '\0';
+
        return buffer;
 }
 
@@ -211,84 +164,234 @@ char *sha1_file_name(const unsigned char *sha1)
        return base;
 }
 
-struct alternate_object_database *alt_odb;
+char *sha1_pack_name(const unsigned char *sha1)
+{
+       static const char hex[] = "0123456789abcdef";
+       static char *name, *base, *buf;
+       int i;
+
+       if (!base) {
+               const char *sha1_file_directory = get_object_directory();
+               int len = strlen(sha1_file_directory);
+               base = xmalloc(len + 60);
+               sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
+               name = base + len + 11;
+       }
+
+       buf = name;
+
+       for (i = 0; i < 20; i++) {
+               unsigned int val = *sha1++;
+               *buf++ = hex[val >> 4];
+               *buf++ = hex[val & 0xf];
+       }
+       
+       return base;
+}
+
+char *sha1_pack_index_name(const unsigned char *sha1)
+{
+       static const char hex[] = "0123456789abcdef";
+       static char *name, *base, *buf;
+       int i;
+
+       if (!base) {
+               const char *sha1_file_directory = get_object_directory();
+               int len = strlen(sha1_file_directory);
+               base = xmalloc(len + 60);
+               sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
+               name = base + len + 11;
+       }
+
+       buf = name;
+
+       for (i = 0; i < 20; i++) {
+               unsigned int val = *sha1++;
+               *buf++ = hex[val >> 4];
+               *buf++ = hex[val & 0xf];
+       }
+       
+       return base;
+}
+
+struct alternate_object_database *alt_odb_list;
+static struct alternate_object_database **alt_odb_tail;
+
+static void read_info_alternates(const char * alternates, int depth);
 
 /*
  * Prepare alternate object database registry.
- * alt_odb points at an array of struct alternate_object_database.
- * This array is terminated with an element that has both its base
- * and name set to NULL.  alt_odb[n] comes from n'th non-empty
- * element from colon separated ALTERNATE_DB_ENVIRONMENT environment
- * variable, and its base points at a statically allocated buffer
- * that contains "/the/directory/corresponding/to/.git/objects/...",
- * while its name points just after the slash at the end of
- * ".git/objects/" in the example above, and has enough space to hold
- * 40-byte hex SHA1, an extra slash for the first level indirection,
- * and the terminating NUL.
- * This function allocates the alt_odb array and all the strings
- * pointed by base fields of the array elements with one xmalloc();
- * the string pool immediately follows the array.
+ *
+ * The variable alt_odb_list points at the list of struct
+ * alternate_object_database.  The elements on this list come from
+ * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
+ * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
+ * whose contents is similar to that environment variable but can be
+ * LF separated.  Its base points at a statically allocated buffer that
+ * contains "/the/directory/corresponding/to/.git/objects/...", while
+ * its name points just after the slash at the end of ".git/objects/"
+ * in the example above, and has enough space to hold 40-byte hex
+ * SHA1, an extra slash for the first level indirection, and the
+ * terminating NUL.
  */
-void prepare_alt_odb(void)
+static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
+{
+       struct stat st;
+       const char *objdir = get_object_directory();
+       struct alternate_object_database *ent;
+       struct alternate_object_database *alt;
+       /* 43 = 40-byte + 2 '/' + terminating NUL */
+       int pfxlen = len;
+       int entlen = pfxlen + 43;
+       int base_len = -1;
+
+       if (*entry != '/' && 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);
+
+       if (*entry != '/' && relative_base) {
+               memcpy(ent->base, relative_base, base_len - 1);
+               ent->base[base_len - 1] = '/';
+               memcpy(ent->base + base_len, entry, len);
+       }
+       else
+               memcpy(ent->base, entry, pfxlen);
+
+       ent->name = ent->base + pfxlen + 1;
+       ent->base[pfxlen + 3] = '/';
+       ent->base[pfxlen] = ent->base[entlen-1] = 0;
+
+       /* Detect cases where alternate disappeared */
+       if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
+               error("object directory %s does not exist; "
+                     "check .git/objects/info/alternates.",
+                     ent->base);
+               free(ent);
+               return -1;
+       }
+
+       /* Prevent the common mistake of listing the same
+        * thing twice, or object directory itself.
+        */
+       for (alt = alt_odb_list; alt; alt = alt->next) {
+               if (!memcmp(ent->base, alt->base, pfxlen)) {
+                       free(ent);
+                       return -1;
+               }
+       }
+       if (!memcmp(ent->base, objdir, pfxlen)) {
+               free(ent);
+               return -1;
+       }
+
+       /* add the alternate entry */
+       *alt_odb_tail = ent;
+       alt_odb_tail = &(ent->next);
+       ent->next = NULL;
+
+       /* recursively add alternates */
+       read_info_alternates(ent->base, depth + 1);
+
+       ent->base[pfxlen] = '/';
+
+       return 0;
+}
+
+static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
+                                const char *relative_base, int depth)
 {
-       int pass, totlen, i;
        const char *cp, *last;
-       char *op = NULL;
-       const char *alt = gitenv(ALTERNATE_DB_ENVIRONMENT) ? : "";
 
-       if (alt_odb)
+       if (depth > 5) {
+               error("%s: ignoring alternate object stores, nesting too deep.",
+                               relative_base);
                return;
-       /* The first pass counts how large an area to allocate to
-        * hold the entire alt_odb structure, including array of
-        * structs and path buffers for them.  The second pass fills
-        * the structure and prepares the path buffers for use by
-        * fill_sha1_path().
-        */
-       for (totlen = pass = 0; pass < 2; pass++) {
-               last = alt;
-               i = 0;
-               do {
-                       cp = strchr(last, ':') ? : last + strlen(last);
-                       if (last != cp) {
-                               /* 43 = 40-byte + 2 '/' + terminating NUL */
-                               int pfxlen = cp - last;
-                               int entlen = pfxlen + 43;
-                               if (pass == 0)
-                                       totlen += entlen;
-                               else {
-                                       alt_odb[i].base = op;
-                                       alt_odb[i].name = op + pfxlen + 1;
-                                       memcpy(op, last, pfxlen);
-                                       op[pfxlen] = op[pfxlen + 3] = '/';
-                                       op[entlen-1] = 0;
-                                       op += entlen;
-                               }
-                               i++;
-                       }
-                       while (*cp && *cp == ':')
+       }
+
+       last = alt;
+       while (last < ep) {
+               cp = last;
+               if (cp < ep && *cp == '#') {
+                       while (cp < ep && *cp != sep)
                                cp++;
-                       last = cp;
-               } while (*cp);
-               if (pass)
-                       break;
-               alt_odb = xmalloc(sizeof(*alt_odb) * (i + 1) + totlen);
-               alt_odb[i].base = alt_odb[i].name = NULL;
-               op = (char*)(&alt_odb[i+1]);
+                       last = cp + 1;
+                       continue;
+               }
+               while (cp < ep && *cp != sep)
+                       cp++;
+               if (last != cp) {
+                       if ((*last != '/') && depth) {
+                               error("%s: ignoring relative alternate object store %s",
+                                               relative_base, last);
+                       } else {
+                               link_alt_odb_entry(last, cp - last,
+                                               relative_base, depth);
+                       }
+               }
+               while (cp < ep && *cp == sep)
+                       cp++;
+               last = cp;
+       }
+}
+
+static void read_info_alternates(const char * relative_base, int depth)
+{
+       char *map;
+       struct stat st;
+       char path[PATH_MAX];
+       int fd;
+
+       sprintf(path, "%s/info/alternates", relative_base);
+       fd = open(path, O_RDONLY);
+       if (fd < 0)
+               return;
+       if (fstat(fd, &st) || (st.st_size == 0)) {
+               close(fd);
+               return;
        }
+       map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+       close(fd);
+       if (map == MAP_FAILED)
+               return;
+
+       link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
+
+       munmap(map, st.st_size);
+}
+
+void prepare_alt_odb(void)
+{
+       char *alt;
+
+       alt = getenv(ALTERNATE_DB_ENVIRONMENT);
+       if (!alt) alt = "";
+
+       if (alt_odb_tail)
+               return;
+       alt_odb_tail = &alt_odb_list;
+       link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
+
+       read_info_alternates(get_object_directory(), 0);
 }
 
 static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
 {
-       int i;
        char *name = sha1_file_name(sha1);
+       struct alternate_object_database *alt;
 
        if (!stat(name, st))
                return name;
        prepare_alt_odb();
-       for (i = 0; (name = alt_odb[i].name) != NULL; i++) {
+       for (alt = alt_odb_list; alt; alt = alt->next) {
+               name = alt->name;
                fill_sha1_path(name, sha1);
-               if (!stat(alt_odb[i].base, st))
-                       return alt_odb[i].base;
+               if (!stat(alt->base, st))
+                       return alt->base;
        }
        return NULL;
 }
@@ -371,6 +474,14 @@ void unuse_packed_git(struct packed_git *p)
 
 int use_packed_git(struct packed_git *p)
 {
+       if (!p->pack_size) {
+               struct stat st;
+               // We created the struct before we had the pack
+               stat(p->pack_name, &st);
+               if (!S_ISREG(st.st_mode))
+                       die("packfile %s not a regular file", p->pack_name);
+               p->pack_size = st.st_size;
+       }
        if (!p->pack_base) {
                int fd;
                struct stat st;
@@ -398,20 +509,23 @@ int use_packed_git(struct packed_git *p)
                 * this is cheap.
                 */
                if (memcmp((char*)(p->index_base) + p->index_size - 40,
-                          p->pack_base + p->pack_size - 20, 20))
+                          p->pack_base + p->pack_size - 20, 20)) {
+                             
                        die("packfile %s does not match index.", p->pack_name);
+               }
        }
        p->pack_last_used = pack_used_ctr++;
        p->pack_use_cnt++;
        return 0;
 }
 
-struct packed_git *add_packed_git(char *path, int path_len)
+struct packed_git *add_packed_git(char *path, int path_len, int local)
 {
        struct stat st;
        struct packed_git *p;
        unsigned long idx_size;
        void *idx_map;
+       unsigned char sha1[20];
 
        if (check_packed_git_idx(path, &idx_size, &idx_map))
                return NULL;
@@ -434,10 +548,50 @@ struct packed_git *add_packed_git(char *path, int path_len)
        p->pack_base = NULL;
        p->pack_last_used = 0;
        p->pack_use_cnt = 0;
+       p->pack_local = local;
+       if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
+               memcpy(p->sha1, sha1, 20);
+       return p;
+}
+
+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;
+
+       if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
+               return NULL;
+
+       path = sha1_pack_name(sha1);
+
+       p = xmalloc(sizeof(*p) + strlen(path) + 2);
+       strcpy(p->pack_name, path);
+       p->index_size = idx_size;
+       p->pack_size = 0;
+       p->index_base = idx_map;
+       p->next = NULL;
+       p->pack_base = NULL;
+       p->pack_last_used = 0;
+       p->pack_use_cnt = 0;
+       memcpy(p->sha1, sha1, 20);
        return p;
 }
 
-static void prepare_packed_git_one(char *objdir)
+void install_packed_git(struct packed_git *pack)
+{
+       pack->next = packed_git;
+       packed_git = pack;
+}
+
+static void prepare_packed_git_one(char *objdir, int local)
 {
        char path[PATH_MAX];
        int len;
@@ -447,8 +601,12 @@ static void prepare_packed_git_one(char *objdir)
        sprintf(path, "%s/pack", objdir);
        len = strlen(path);
        dir = opendir(path);
-       if (!dir)
+       if (!dir) {
+               if (errno != ENOENT)
+                       error("unable to open object pack directory: %s: %s",
+                             path, strerror(errno));
                return;
+       }
        path[len++] = '/';
        while ((de = readdir(dir)) != NULL) {
                int namelen = strlen(de->d_name);
@@ -459,7 +617,13 @@ static void prepare_packed_git_one(char *objdir)
 
                /* we have .idx.  Is it a file we can map? */
                strcpy(path + len, de->d_name);
-               p = add_packed_git(path, len + namelen);
+               for (p = packed_git; p; p = p->next) {
+                       if (!memcmp(path, p->pack_name, len + namelen - 4))
+                               break;
+               }
+               if (p)
+                       continue;
+               p = add_packed_git(path, len + namelen, local);
                if (!p)
                        continue;
                p->next = packed_git;
@@ -468,20 +632,27 @@ static void prepare_packed_git_one(char *objdir)
        closedir(dir);
 }
 
+static int prepare_packed_git_run_once = 0;
 void prepare_packed_git(void)
 {
-       int i;
-       static int run_once = 0;
+       struct alternate_object_database *alt;
 
-       if (run_once++)
+       if (prepare_packed_git_run_once)
                return;
-
-       prepare_packed_git_one(get_object_directory());
+       prepare_packed_git_one(get_object_directory(), 1);
        prepare_alt_odb();
-       for (i = 0; alt_odb[i].base != NULL; i++) {
-               alt_odb[i].name[0] = 0;
-               prepare_packed_git_one(alt_odb[i].base);
+       for (alt = alt_odb_list; alt; alt = alt->next) {
+               alt->name[-1] = 0;
+               prepare_packed_git_one(alt->base, 0);
+               alt->name[-1] = '/';
        }
+       prepare_packed_git_run_once = 1;
+}
+
+static void reprepare_packed_git(void)
+{
+       prepare_packed_git_run_once = 0;
+       prepare_packed_git();
 }
 
 int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
@@ -684,10 +855,12 @@ static int packed_delta_info(unsigned char *base_sha1,
                 * the result size.
                 */
                data = delta_head;
-               get_delta_hdr_size(&data); /* ignore base size */
+
+               /* ignore base size */
+               get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
 
                /* Read the result size */
-               result_size = get_delta_hdr_size(&data);
+               result_size = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
                *sizep = result_size;
        }
        return 0;
@@ -721,25 +894,46 @@ static unsigned long unpack_object_header(struct packed_git *p, unsigned long of
        return offset;
 }
 
+int check_reuse_pack_delta(struct packed_git *p, unsigned long offset,
+                          unsigned char *base, unsigned long *sizep,
+                          enum object_type *kindp)
+{
+       unsigned long ptr;
+       int status = -1;
+
+       use_packed_git(p);
+       ptr = offset;
+       ptr = unpack_object_header(p, ptr, kindp, sizep);
+       if (*kindp != OBJ_DELTA)
+               goto done;
+       memcpy(base, p->pack_base + ptr, 20);
+       status = 0;
+ done:
+       unuse_packed_git(p);
+       return status;
+}
+
 void packed_object_info_detail(struct pack_entry *e,
                               char *type,
                               unsigned long *size,
                               unsigned long *store_size,
-                              int *delta_chain_length,
+                              unsigned int *delta_chain_length,
                               unsigned char *base_sha1)
 {
        struct packed_git *p = e->p;
-       unsigned long offset, left;
+       unsigned long offset;
        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;
+               unsigned int chain_length = 0;
+               if (p->pack_size <= offset + 20)
+                       die("pack file %s records an incomplete delta base",
+                           p->pack_name);
                memcpy(base_sha1, pack, 20);
                do {
                        struct pack_entry base_ent;
@@ -755,19 +949,20 @@ void packed_object_info_detail(struct pack_entry *e,
        }
        switch (kind) {
        case OBJ_COMMIT:
-               strcpy(type, "commit");
+               strcpy(type, commit_type);
                break;
        case OBJ_TREE:
-               strcpy(type, "tree");
+               strcpy(type, tree_type);
                break;
        case OBJ_BLOB:
-               strcpy(type, "blob");
+               strcpy(type, blob_type);
                break;
        case OBJ_TAG:
-               strcpy(type, "tag");
+               strcpy(type, tag_type);
                break;
        default:
-               die("corrupted pack file");
+               die("corrupted pack file %s containing object of kind %d",
+                   p->pack_name, kind);
        }
        *store_size = 0; /* notyet */
 }
@@ -794,19 +989,20 @@ static int packed_object_info(struct pack_entry *entry,
                unuse_packed_git(p);
                return retval;
        case OBJ_COMMIT:
-               strcpy(type, "commit");
+               strcpy(type, commit_type);
                break;
        case OBJ_TREE:
-               strcpy(type, "tree");
+               strcpy(type, tree_type);
                break;
        case OBJ_BLOB:
-               strcpy(type, "blob");
+               strcpy(type, blob_type);
                break;
        case OBJ_TAG:
-               strcpy(type, "tag");
+               strcpy(type, tag_type);
                break;
        default:
-               die("corrupted pack file");
+               die("corrupted pack file %s containing object of kind %d",
+                   p->pack_name, kind);
        }
        if (sizep)
                *sizep = size;
@@ -832,6 +1028,16 @@ static void *unpack_delta_entry(unsigned char *base_sha1,
 
        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));
+       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));
+
        data = base_sha1 + 20;
        data_size = left - 20;
        delta_data = xmalloc(delta_size);
@@ -849,14 +1055,6 @@ static void *unpack_delta_entry(unsigned char *base_sha1,
        if ((st != Z_STREAM_END) || stream.total_out != delta_size)
                die("delta data unpack failed");
 
-       /* 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));
        result = patch_delta(base, base_size,
                             delta_data, delta_size,
                             &result_size);
@@ -906,7 +1104,7 @@ 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;
 }
 
@@ -928,16 +1126,16 @@ void *unpack_entry_gently(struct pack_entry *entry,
                retval = unpack_delta_entry(pack, size, left, type, sizep, p);
                return retval;
        case OBJ_COMMIT:
-               strcpy(type, "commit");
+               strcpy(type, commit_type);
                break;
        case OBJ_TREE:
-               strcpy(type, "tree");
+               strcpy(type, tree_type);
                break;
        case OBJ_BLOB:
-               strcpy(type, "blob");
+               strcpy(type, blob_type);
                break;
        case OBJ_TAG:
-               strcpy(type, "tag");
+               strcpy(type, tag_type);
                break;
        default:
                return NULL;
@@ -975,7 +1173,7 @@ int find_pack_entry_one(const unsigned char *sha1,
                int mi = (lo + hi) / 2;
                int cmp = memcmp(index + 24 * mi + 4, sha1, 20);
                if (!cmp) {
-                       e->offset = ntohl(*((int*)(index + 24 * mi)));
+                       e->offset = ntohl(*((unsigned int *)(index + 24 * mi)));
                        memcpy(e->sha1, sha1, 20);
                        e->p = p;
                        return 1;
@@ -1000,6 +1198,20 @@ static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
        return 0;
 }
 
+struct packed_git *find_sha1_pack(const unsigned char *sha1, 
+                                 struct packed_git *packs)
+{
+       struct packed_git *p;
+       struct pack_entry e;
+
+       for (p = packs; p; p = p->next) {
+               if (find_pack_entry_one(sha1, &e, p))
+                       return p;
+       }
+       return NULL;
+       
+}
+
 int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
 {
        int status;
@@ -1012,9 +1224,12 @@ int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep
        if (!map) {
                struct pack_entry e;
 
-               if (!find_pack_entry(sha1, &e))
-                       return error("unable to find %s", sha1_to_hex(sha1));
-               return packed_object_info(&e, type, sizep);
+               if (find_pack_entry(sha1, &e))
+                       return packed_object_info(&e, type, sizep);
+               reprepare_packed_git();
+               if (find_pack_entry(sha1, &e))
+                       return packed_object_info(&e, type, sizep);
+               return error("unable to find %s", sha1_to_hex(sha1));
        }
        if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
                status = error("unable to unpack %s header",
@@ -1056,6 +1271,9 @@ void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size
                munmap(map, mapsize);
                return buf;
        }
+       reprepare_packed_git();
+       if (find_pack_entry(sha1, &e))
+               return read_packed_sha1(sha1, type, size);
        return NULL;
 }
 
@@ -1084,9 +1302,9 @@ void *read_object_with_reference(const unsigned char *sha1,
                        return buffer;
                }
                /* Handle references */
-               else if (!strcmp(type, "commit"))
+               else if (!strcmp(type, commit_type))
                        ref_type = "tree ";
-               else if (!strcmp(type, "tag"))
+               else if (!strcmp(type, tag_type))
                        ref_type = "object ";
                else {
                        free(buffer);
@@ -1099,6 +1317,7 @@ void *read_object_with_reference(const unsigned char *sha1,
                        free(buffer);
                        return NULL;
                }
+               free(buffer);
                /* Now we have the ID of the referred-to object in
                 * actual_sha1.  Check again. */
        }
@@ -1125,6 +1344,98 @@ char *write_sha1_file_prepare(void *buf,
        return sha1_file_name(sha1);
 }
 
+/*
+ * Link the tempfile to the final place, possibly creating the
+ * last directory level as you do so.
+ *
+ * Returns the errno on failure, 0 on success.
+ */
+static int link_temp_to_file(const char *tmpfile, char *filename)
+{
+       int ret;
+
+       if (!link(tmpfile, filename))
+               return 0;
+
+       /*
+        * Try to mkdir the last path component if that failed
+        * with an ENOENT.
+        *
+        * Re-try the "link()" regardless of whether the mkdir
+        * succeeds, since a race might mean that somebody
+        * else succeeded.
+        */
+       ret = errno;
+       if (ret == ENOENT) {
+               char *dir = strrchr(filename, '/');
+               if (dir) {
+                       *dir = 0;
+                       mkdir(filename, 0777);
+                       if (adjust_shared_perm(filename))
+                               return -2;
+                       *dir = '/';
+                       if (!link(tmpfile, filename))
+                               return 0;
+                       ret = errno;
+               }
+       }
+       return ret;
+}
+
+/*
+ * Move the just written object into its final resting place
+ */
+int move_temp_to_file(const char *tmpfile, char *filename)
+{
+       int ret = link_temp_to_file(tmpfile, filename);
+
+       /*
+        * Coda hack - coda doesn't like cross-directory links,
+        * so we fall back to a rename, which will mean that it
+        * won't be able to check collisions, but that's not a
+        * big deal.
+        *
+        * The same holds for FAT formatted media.
+        *
+        * When this succeeds, we just return 0. We have nothing
+        * left to unlink.
+        */
+       if (ret && ret != EEXIST) {
+               if (!rename(tmpfile, filename))
+                       return 0;
+               ret = errno;
+       }
+       unlink(tmpfile);
+       if (ret) {
+               if (ret != EEXIST) {
+                       fprintf(stderr, "unable to write sha1 filename %s: %s\n", filename, strerror(ret));
+                       return -1;
+               }
+               /* FIXME!!! Collision check here ? */
+       }
+
+       return 0;
+}
+
+static int write_buffer(int fd, const void *buf, size_t len)
+{
+       while (len) {
+               ssize_t size;
+
+               size = write(fd, buf, len);
+               if (!size)
+                       return error("file write: disk full");
+               if (size < 0) {
+                       if (errno == EINTR || errno == EAGAIN)
+                               continue;
+                       return error("file write error (%s)", strerror(errno));
+               }
+               len -= size;
+               buf += size;
+       }
+       return 0;
+}
+
 int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
 {
        int size;
@@ -1134,7 +1445,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha
        char *filename;
        static char tmpfile[PATH_MAX];
        unsigned char hdr[50];
-       int fd, hdrlen, ret;
+       int fd, hdrlen;
 
        /* Normally if we have it in the pack then we do not bother writing
         * it out into .git/objects/??/?{38} file.
@@ -1155,7 +1466,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha
        }
 
        if (errno != ENOENT) {
-               fprintf(stderr, "sha1 file %s: %s", filename, strerror(errno));
+               fprintf(stderr, "sha1 file %s: %s\n", filename, strerror(errno));
                return -1;
        }
 
@@ -1163,7 +1474,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha
 
        fd = mkstemp(tmpfile);
        if (fd < 0) {
-               fprintf(stderr, "unable to create temporary sha1 filename %s: %s", tmpfile, strerror(errno));
+               fprintf(stderr, "unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
                return -1;
        }
 
@@ -1191,115 +1502,98 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha
        deflateEnd(&stream);
        size = stream.total_out;
 
-       if (write(fd, compressed, size) != size)
-               die("unable to write file");
+       if (write_buffer(fd, compressed, size) < 0)
+               die("unable to write sha1 file");
        fchmod(fd, 0444);
        close(fd);
        free(compressed);
 
-       ret = link(tmpfile, filename);
-       if (ret < 0) {
-               ret = errno;
+       return move_temp_to_file(tmpfile, filename);
+}
 
-               /*
-                * Coda hack - coda doesn't like cross-directory links,
-                * so we fall back to a rename, which will mean that it
-                * won't be able to check collisions, but that's not a
-                * big deal.
-                *
-                * When this succeeds, we just return 0. We have nothing
-                * left to unlink.
-                */
-               if (ret == EXDEV && !rename(tmpfile, filename))
-                       return 0;
-       }
-       unlink(tmpfile);
-       if (ret) {
-               if (ret != EEXIST) {
-                       fprintf(stderr, "unable to write sha1 filename %s: %s", filename, strerror(ret));
-                       return -1;
-               }
-               /* FIXME!!! Collision check here ? */
-       }
+/*
+ * We need to unpack and recompress the object for writing
+ * it out to a different file.
+ */
+static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
+{
+       size_t size;
+       z_stream stream;
+       unsigned char *unpacked;
+       unsigned long len;
+       char type[20];
+       char hdr[50];
+       int hdrlen;
+       void *buf;
 
-       return 0;
+       // 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 = (void *)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);
+       free(unpacked);
+
+       *objsize = stream.total_out;
+       return buf;
 }
 
 int write_sha1_to_fd(int fd, const unsigned char *sha1)
 {
-       ssize_t size;
+       int retval;
        unsigned long objsize;
-       int posn = 0;
        void *buf = map_sha1_file_internal(sha1, &objsize);
-       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 = (void *)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;
+       if (buf) {
+               retval = write_buffer(fd, buf, objsize);
+               munmap(buf, objsize);
+               return retval;
        }
 
-       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;
+       buf = repack_object(sha1, &objsize);
+       retval = write_buffer(fd, buf, objsize);
+       free(buf);
+       return retval;
 }
 
-int write_sha1_from_fd(const unsigned char *sha1, int fd)
+int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
+                      size_t bufsize, size_t *bufposn)
 {
-       char *filename = sha1_file_name(sha1);
-
+       char tmpfile[PATH_MAX];
        int local;
        z_stream stream;
        unsigned char real_sha1[20];
-       unsigned char buf[4096];
        unsigned char discard[4096];
        int ret;
        SHA_CTX c;
 
-       local = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
+       snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
 
+       local = mkstemp(tmpfile);
        if (local < 0)
-               return error("Couldn't open %s\n", filename);
+               return error("Couldn't open %s for %s",
+                            tmpfile, sha1_to_hex(sha1));
 
        memset(&stream, 0, sizeof(stream));
 
@@ -1309,41 +1603,65 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd)
 
        do {
                ssize_t size;
-               size = read(fd, buf, 4096);
+               if (*bufposn) {
+                       stream.avail_in = *bufposn;
+                       stream.next_in = (unsigned char *) buffer;
+                       do {
+                               stream.next_out = discard;
+                               stream.avail_out = sizeof(discard);
+                               ret = inflate(&stream, Z_SYNC_FLUSH);
+                               SHA1_Update(&c, discard, sizeof(discard) -
+                                           stream.avail_out);
+                       } while (stream.avail_in && ret == Z_OK);
+                       if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
+                               die("unable to write sha1 file");
+                       memmove(buffer, buffer + *bufposn - stream.avail_in,
+                               stream.avail_in);
+                       *bufposn = stream.avail_in;
+                       if (ret != Z_OK)
+                               break;
+               }
+               size = read(fd, buffer + *bufposn, bufsize - *bufposn);
                if (size <= 0) {
                        close(local);
-                       unlink(filename);
+                       unlink(tmpfile);
                        if (!size)
                                return error("Connection closed?");
                        perror("Reading from connection");
                        return -1;
                }
-               write(local, buf, size);
-               stream.avail_in = size;
-               stream.next_in = buf;
-               do {
-                       stream.next_out = discard;
-                       stream.avail_out = sizeof(discard);
-                       ret = inflate(&stream, Z_SYNC_FLUSH);
-                       SHA1_Update(&c, discard, sizeof(discard) -
-                                   stream.avail_out);
-               } while (stream.avail_in && ret == Z_OK);
-               
-       } while (ret == Z_OK);
+               *bufposn += size;
+       } while (1);
        inflateEnd(&stream);
 
        close(local);
        SHA1_Final(real_sha1, &c);
        if (ret != Z_STREAM_END) {
-               unlink(filename);
+               unlink(tmpfile);
                return error("File %s corrupted", sha1_to_hex(sha1));
        }
        if (memcmp(sha1, real_sha1, 20)) {
-               unlink(filename);
-               return error("File %s has bad hash\n", sha1_to_hex(sha1));
+               unlink(tmpfile);
+               return error("File %s has bad hash", sha1_to_hex(sha1));
        }
-       
-       return 0;
+
+       return move_temp_to_file(tmpfile, sha1_file_name(sha1));
+}
+
+int has_pack_index(const unsigned char *sha1)
+{
+       struct stat st;
+       if (stat(sha1_pack_index_name(sha1), &st))
+               return 0;
+       return 1;
+}
+
+int has_pack_file(const unsigned char *sha1)
+{
+       struct stat st;
+       if (stat(sha1_pack_name(sha1), &st))
+               return 0;
+       return 1;
 }
 
 int has_sha1_pack(const unsigned char *sha1)
@@ -1362,6 +1680,66 @@ int has_sha1_file(const unsigned char *sha1)
        return find_sha1_file(sha1, &st) ? 1 : 0;
 }
 
+/*
+ * reads from fd as long as possible into a supplied buffer of size bytes.
+ * If neccessary the buffer's size is increased using realloc()
+ *
+ * returns 0 if anything went fine and -1 otherwise
+ *
+ * NOTE: both buf and size may change, but even when -1 is returned
+ * you still have to free() it yourself.
+ */
+int read_pipe(int fd, char** return_buf, unsigned long* return_size)
+{
+       char* buf = *return_buf;
+       unsigned long size = *return_size;
+       int iret;
+       unsigned long off = 0;
+
+       do {
+               iret = xread(fd, buf + off, size - off);
+               if (iret > 0) {
+                       off += iret;
+                       if (off == size) {
+                               size *= 2;
+                               buf = realloc(buf, size);
+                       }
+               }
+       } while (iret > 0);
+
+       *return_buf = buf;
+       *return_size = off;
+
+       if (iret < 0)
+               return -1;
+       return 0;
+}
+
+int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
+{
+       unsigned long size = 4096;
+       char *buf = malloc(size);
+       int ret;
+       unsigned char hdr[50];
+       int hdrlen;
+
+       if (read_pipe(fd, &buf, &size)) {
+               free(buf);
+               return -1;
+       }
+
+       if (!type)
+               type = blob_type;
+       if (write_object)
+               ret = write_sha1_file(buf, size, type, sha1);
+       else {
+               write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
+               ret = 0;
+       }
+       free(buf);
+       return ret;
+}
+
 int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
 {
        unsigned long size = st->st_size;
@@ -1378,7 +1756,7 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, con
                return -1;
 
        if (!type)
-               type = "blob";
+               type = blob_type;
        if (write_object)
                ret = write_sha1_file(buf, size, type, sha1);
        else {
@@ -1389,3 +1767,42 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, con
                munmap(buf, size);
        return ret;
 }
+
+int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
+{
+       int fd;
+       char *target;
+
+       switch (st->st_mode & S_IFMT) {
+       case S_IFREG:
+               fd = open(path, O_RDONLY);
+               if (fd < 0)
+                       return error("open(\"%s\"): %s", path,
+                                    strerror(errno));
+               if (index_fd(sha1, fd, st, write_object, NULL) < 0)
+                       return error("%s: failed to insert into database",
+                                    path);
+               break;
+       case S_IFLNK:
+               target = xmalloc(st->st_size+1);
+               if (readlink(path, target, st->st_size+1) != st->st_size) {
+                       char *errstr = strerror(errno);
+                       free(target);
+                       return error("readlink(\"%s\"): %s", path,
+                                    errstr);
+               }
+               if (!write_object) {
+                       unsigned char hdr[50];
+                       int hdrlen;
+                       write_sha1_file_prepare(target, st->st_size, blob_type,
+                                               sha1, hdr, &hdrlen);
+               } else if (write_sha1_file(target, st->st_size, blob_type, sha1))
+                       return error("%s: failed to insert into database",
+                                    path);
+               free(target);
+               break;
+       default:
+               return error("%s: unsupported file type", path);
+       }
+       return 0;
+}