Rename warn() to warning() to fix symbol conflicts on BSD and Mac OS
[gitweb.git] / fast-import.c
index 1c74b90c84f1c100cbf593a0e7bcd1fdafe40feb..cdd629d6bc547609daabab6c1f3b73939fddb7b9 100644 (file)
@@ -4,9 +4,10 @@ Format of STDIN stream:
   stream ::= cmd*;
 
   cmd ::= new_blob
-        | new_branch
         | new_commit
         | new_tag
+        | reset_branch
+        | checkpoint
         ;
 
   new_blob ::= 'blob' lf
@@ -14,30 +15,37 @@ Format of STDIN stream:
     file_content;
   file_content ::= data;
 
-  new_branch ::= 'branch' sp ref_str lf
-    ('from' sp (ref_str | hexsha1 | sha1exp_str | idnum) lf)?
-    lf;
-
   new_commit ::= 'commit' sp ref_str lf
-       mark?
-       ('author' sp name '<' email '>' ts tz lf)?
-       'committer' sp name '<' email '>' ts tz lf
-       commit_msg
+    mark?
+    ('author' sp name '<' email '>' when lf)?
+    'committer' sp name '<' email '>' when lf
+    commit_msg
+    ('from' sp (ref_str | hexsha1 | sha1exp_str | idnum) lf)?
+    ('merge' sp (ref_str | hexsha1 | sha1exp_str | idnum) lf)*
     file_change*
     lf;
   commit_msg ::= data;
 
-  file_change ::= 'M' sp mode sp (hexsha1 | idnum) sp path_str lf
-                | 'D' sp path_str lf
-                ;
-  mode ::= '644' | '755';
+  file_change ::= file_clr | file_del | file_obm | file_inm;
+  file_clr ::= 'deleteall' lf;
+  file_del ::= 'D' sp path_str lf;
+  file_obm ::= 'M' sp mode sp (hexsha1 | idnum) sp path_str lf;
+  file_inm ::= 'M' sp mode sp 'inline' sp path_str lf
+    data;
 
   new_tag ::= 'tag' sp tag_str lf
     'from' sp (ref_str | hexsha1 | sha1exp_str | idnum) lf
-       'tagger' sp name '<' email '>' ts tz lf
+       'tagger' sp name '<' email '>' when lf
     tag_msg;
   tag_msg ::= data;
 
+  reset_branch ::= 'reset' sp ref_str lf
+    ('from' sp (ref_str | hexsha1 | sha1exp_str | idnum) lf)?
+    lf;
+
+  checkpoint ::= 'checkpoint' lf
+    lf;
+
      # note: the first idnum in a stream should be 1 and subsequent
      # idnums should not have gaps between values as this will cause
      # the stream parser to reserve space for the gapped values.  An
@@ -45,14 +53,21 @@ Format of STDIN stream:
      # a new mark directive with the old idnum.
         #
   mark ::= 'mark' sp idnum lf;
+  data ::= (delimited_data | exact_data)
+    lf;
+
+    # note: delim may be any string but must not contain lf.
+    # data_line may contain any data but must not be exactly
+    # delim.
+  delimited_data ::= 'data' sp '<<' delim lf
+    (data_line lf)*
+       delim lf;
 
      # note: declen indicates the length of binary_data in bytes.
-     # declen does not include the lf preceeding or trailing the
-     # binary data.
+     # declen does not include the lf preceeding the binary data.
      #
-  data ::= 'data' sp declen lf
-    binary_data
-       lf;
+  exact_data ::= 'data' sp declen lf
+    binary_data;
 
      # note: quoted strings are C-style quoting supporting \c for
      # common escapes of 'c' (e..g \n, \t, \\, \") or \nnn where nnn
@@ -61,14 +76,23 @@ Format of STDIN stream:
      # stream formatting is: \, " and LF.  Otherwise these values
         # are UTF8.
      #
-  ref_str     ::= ref     | '"' quoted(ref)     '"' ;
-  sha1exp_str ::= sha1exp | '"' quoted(sha1exp) '"' ;
-  tag_str     ::= tag     | '"' quoted(tag)     '"' ;
+  ref_str     ::= ref;
+  sha1exp_str ::= sha1exp;
+  tag_str     ::= tag;
   path_str    ::= path    | '"' quoted(path)    '"' ;
+  mode        ::= '100644' | '644'
+                | '100755' | '755'
+                | '120000'
+                ;
 
   declen ::= # unsigned 32 bit value, ascii base10 notation;
+  bigint ::= # unsigned integer value, ascii base10 notation;
   binary_data ::= # file content, not interpreted;
 
+  when         ::= raw_when | rfc2822_when;
+  raw_when     ::= ts sp tz;
+  rfc2822_when ::= # Valid RFC 2822 date and time;
+
   sp ::= # ASCII space character;
   lf ::= # ASCII newline (LF) character;
 
@@ -76,7 +100,7 @@ Format of STDIN stream:
         # an idnum.  This is to distinguish it from a ref or tag name as
      # GIT does not permit ':' in ref or tag strings.
         #
-  idnum   ::= ':' declen;
+  idnum   ::= ':' bigint;
   path    ::= # GIT style file path, e.g. "a/b/c";
   ref     ::= # GIT ref name, e.g. "refs/heads/MOZ_GECKO_EXPERIMENT";
   tag     ::= # GIT tag name, e.g. "FIREFOX_1_5";
@@ -98,6 +122,7 @@ Format of STDIN stream:
 #include "object.h"
 #include "blob.h"
 #include "tree.h"
+#include "commit.h"
 #include "delta.h"
 #include "pack.h"
 #include "refs.h"
@@ -105,11 +130,15 @@ Format of STDIN stream:
 #include "strbuf.h"
 #include "quote.h"
 
+#define PACK_ID_BITS 16
+#define MAX_PACK_ID ((1<<PACK_ID_BITS)-1)
+
 struct object_entry
 {
        struct object_entry *next;
-       enum object_type type;
-       unsigned long offset;
+       uint32_t offset;
+       unsigned type : TYPE_BITS;
+       unsigned pack_id : PACK_ID_BITS;
        unsigned char sha1[20];
 };
 
@@ -123,19 +152,20 @@ struct object_entry_pool
 
 struct mark_set
 {
-       int shift;
        union {
                struct object_entry *marked[1024];
                struct mark_set *sets[1024];
        } data;
+       unsigned int shift;
 };
 
 struct last_object
 {
        void *data;
-       unsigned int len;
+       unsigned long len;
+       uint32_t offset;
        unsigned int depth;
-       unsigned char sha1[20];
+       unsigned no_free:1;
 };
 
 struct mem_pool
@@ -149,7 +179,7 @@ struct mem_pool
 struct atom_str
 {
        struct atom_str *next_atom;
-       int str_len;
+       unsigned short str_len;
        char str_dat[FLEX_ARRAY]; /* more */
 };
 
@@ -158,14 +188,18 @@ struct tree_entry
 {
        struct tree_content *tree;
        struct atom_str* name;
-       unsigned int mode;
-       unsigned char sha1[20];
+       struct tree_entry_ms
+       {
+               uint16_t mode;
+               unsigned char sha1[20];
+       } versions[2];
 };
 
 struct tree_content
 {
        unsigned int entry_capacity; /* must match avail_tree_content */
        unsigned int entry_count;
+       unsigned int delta_depth;
        struct tree_entry *entries[FLEX_ARRAY]; /* more */
 };
 
@@ -180,8 +214,10 @@ struct branch
        struct branch *table_next_branch;
        struct branch *active_next_branch;
        const char *name;
-       unsigned long last_commit;
        struct tree_entry branch_tree;
+       uintmax_t last_commit;
+       unsigned active : 1;
+       unsigned pack_id : PACK_ID_BITS;
        unsigned char sha1[20];
 };
 
@@ -189,21 +225,44 @@ struct tag
 {
        struct tag *next_tag;
        const char *name;
+       unsigned int pack_id;
        unsigned char sha1[20];
 };
 
+struct dbuf
+{
+       void *buffer;
+       size_t capacity;
+};
 
-/* Stats and misc. counters */
+struct hash_list
+{
+       struct hash_list *next;
+       unsigned char sha1[20];
+};
+
+typedef enum {
+       WHENSPEC_RAW = 1,
+       WHENSPEC_RFC2822,
+       WHENSPEC_NOW,
+} whenspec_type;
+
+/* Configured limits on output */
 static unsigned long max_depth = 10;
-static unsigned long alloc_count;
+static off_t max_packsize = (1LL << 32) - 1;
+static int force_update;
+
+/* Stats and misc. counters */
+static uintmax_t alloc_count;
+static uintmax_t marks_set_count;
+static uintmax_t object_count_by_type[1 << TYPE_BITS];
+static uintmax_t duplicate_count_by_type[1 << TYPE_BITS];
+static uintmax_t delta_count_by_type[1 << TYPE_BITS];
+static unsigned long object_count;
 static unsigned long branch_count;
 static unsigned long branch_load_count;
-static unsigned long remap_count;
-static unsigned long object_count;
-static unsigned long duplicate_count;
-static unsigned long marks_set_count;
-static unsigned long object_count_by_type[9];
-static unsigned long duplicate_count_by_type[9];
+static int failure;
+static FILE *pack_edges;
 
 /* Memory pools */
 static size_t mem_pool_alloc = 2*1024*1024 - sizeof(struct mem_pool);
@@ -216,17 +275,17 @@ static unsigned int atom_cnt;
 static struct atom_str **atom_table;
 
 /* The .pack file being generated */
-static int pack_fd;
+static unsigned int pack_id;
+static struct packed_git *pack_data;
+static struct packed_git **all_packs;
 static unsigned long pack_size;
-static unsigned char pack_sha1[20];
-static void* pack_base;
-static size_t pack_mlen;
 
 /* Table of objects we've written. */
-static unsigned int object_entry_alloc = 1000;
+static unsigned int object_entry_alloc = 5000;
 static struct object_entry_pool *blocks;
 static struct object_entry *object_table[1 << 16];
 static struct mark_set *marks;
+static const char* mark_file;
 
 /* Our last blob */
 static struct last_object last_blob;
@@ -236,6 +295,8 @@ static unsigned int tree_entry_alloc = 1000;
 static void *avail_tree_entry;
 static unsigned int avail_tree_table_sz = 100;
 static struct avail_tree_content **avail_tree_table;
+static struct dbuf old_tree;
+static struct dbuf new_tree;
 
 /* Branch data */
 static unsigned long max_active_branches = 5;
@@ -249,11 +310,13 @@ static struct tag *first_tag;
 static struct tag *last_tag;
 
 /* Input stream parsing */
+static whenspec_type whenspec = WHENSPEC_RAW;
 static struct strbuf command_buf;
-static unsigned long next_mark;
+static uintmax_t next_mark;
+static struct dbuf new_data;
 
 
-static void alloc_objects(int cnt)
+static void alloc_objects(unsigned int cnt)
 {
        struct object_entry_pool *b;
 
@@ -266,7 +329,7 @@ static void alloc_objects(int cnt)
        alloc_count += cnt;
 }
 
-static struct object_entrynew_object(unsigned char *sha1)
+static struct object_entry *new_object(unsigned char *sha1)
 {
        struct object_entry *e;
 
@@ -274,28 +337,28 @@ static struct object_entry* new_object(unsigned char *sha1)
                alloc_objects(object_entry_alloc);
 
        e = blocks->next_free++;
-       memcpy(e->sha1, sha1, sizeof(e->sha1));
+       hashcpy(e->sha1, sha1);
        return e;
 }
 
-static struct object_entryfind_object(unsigned char *sha1)
+static struct object_entry *find_object(unsigned char *sha1)
 {
        unsigned int h = sha1[0] << 8 | sha1[1];
        struct object_entry *e;
        for (e = object_table[h]; e; e = e->next)
-               if (!memcmp(sha1, e->sha1, sizeof(e->sha1)))
+               if (!hashcmp(sha1, e->sha1))
                        return e;
        return NULL;
 }
 
-static struct object_entryinsert_object(unsigned char *sha1)
+static struct object_entry *insert_object(unsigned char *sha1)
 {
        unsigned int h = sha1[0] << 8 | sha1[1];
        struct object_entry *e = object_table[h];
        struct object_entry *p = NULL;
 
        while (e) {
-               if (!memcmp(sha1, e->sha1, sizeof(e->sha1)))
+               if (!hashcmp(sha1, e->sha1))
                        return e;
                p = e;
                e = e->next;
@@ -319,7 +382,7 @@ static unsigned int hc_str(const char *s, size_t len)
        return r;
 }
 
-static voidpool_alloc(size_t len)
+static void *pool_alloc(size_t len)
 {
        struct mem_pool *p;
        void *r;
@@ -342,11 +405,14 @@ static void* pool_alloc(size_t len)
        }
 
        r = p->next_free;
+       /* round out to a pointer alignment */
+       if (len & (sizeof(void*) - 1))
+               len += sizeof(void*) - (len & (sizeof(void*) - 1));
        p->next_free += len;
        return r;
 }
 
-static voidpool_calloc(size_t count, size_t size)
+static void *pool_calloc(size_t count, size_t size)
 {
        size_t len = count * size;
        void *r = pool_alloc(len);
@@ -354,14 +420,25 @@ static void* pool_calloc(size_t count, size_t size)
        return r;
 }
 
-static charpool_strdup(const char *s)
+static char *pool_strdup(const char *s)
 {
        char *r = pool_alloc(strlen(s) + 1);
        strcpy(r, s);
        return r;
 }
 
-static void insert_mark(unsigned long idnum, struct object_entry *oe)
+static void size_dbuf(struct dbuf *b, size_t maxlen)
+{
+       if (b->buffer) {
+               if (b->capacity >= maxlen)
+                       return;
+               free(b->buffer);
+       }
+       b->capacity = ((maxlen / 1024) + 1) * 1024;
+       b->buffer = xmalloc(b->capacity);
+}
+
+static void insert_mark(uintmax_t idnum, struct object_entry *oe)
 {
        struct mark_set *s = marks;
        while ((idnum >> s->shift) >= 1024) {
@@ -371,7 +448,7 @@ static void insert_mark(unsigned long idnum, struct object_entry *oe)
                marks = s;
        }
        while (s->shift) {
-               unsigned long i = idnum >> s->shift;
+               uintmax_t i = idnum >> s->shift;
                idnum -= i << s->shift;
                if (!s->data.sets[i]) {
                        s->data.sets[i] = pool_calloc(1, sizeof(struct mark_set));
@@ -384,14 +461,14 @@ static void insert_mark(unsigned long idnum, struct object_entry *oe)
        s->data.marked[idnum] = oe;
 }
 
-static struct object_entry* find_mark(unsigned long idnum)
+static struct object_entry *find_mark(uintmax_t idnum)
 {
-       unsigned long orig_idnum = idnum;
+       uintmax_t orig_idnum = idnum;
        struct mark_set *s = marks;
        struct object_entry *oe = NULL;
        if ((idnum >> s->shift) < 1024) {
                while (s && s->shift) {
-                       unsigned long i = idnum >> s->shift;
+                       uintmax_t i = idnum >> s->shift;
                        idnum -= i << s->shift;
                        s = s->data.sets[i];
                }
@@ -399,11 +476,11 @@ static struct object_entry* find_mark(unsigned long idnum)
                        oe = s->data.marked[idnum];
        }
        if (!oe)
-               die("mark :%lu not declared", orig_idnum);
+               die("mark :%" PRIuMAX " not declared", orig_idnum);
        return oe;
 }
 
-static struct atom_str* to_atom(const char *s, size_t len)
+static struct atom_str *to_atom(const char *s, unsigned short len)
 {
        unsigned int hc = hc_str(s, len) % atom_table_sz;
        struct atom_str *c;
@@ -422,7 +499,7 @@ static struct atom_str* to_atom(const char *s, size_t len)
        return c;
 }
 
-static struct branchlookup_branch(const char *name)
+static struct branch *lookup_branch(const char *name)
 {
        unsigned int hc = hc_str(name, strlen(name)) % branch_table_sz;
        struct branch *b;
@@ -433,7 +510,7 @@ static struct branch* lookup_branch(const char *name)
        return NULL;
 }
 
-static struct branchnew_branch(const char *name)
+static struct branch *new_branch(const char *name)
 {
        unsigned int hc = hc_str(name, strlen(name)) % branch_table_sz;
        struct branch* b = lookup_branch(name);
@@ -446,6 +523,10 @@ static struct branch* new_branch(const char *name)
        b = pool_calloc(1, sizeof(struct branch));
        b->name = pool_strdup(name);
        b->table_next_branch = branch_table[hc];
+       b->branch_tree.versions[0].mode = S_IFDIR;
+       b->branch_tree.versions[1].mode = S_IFDIR;
+       b->active = 0;
+       b->pack_id = MAX_PACK_ID;
        branch_table[hc] = b;
        branch_count++;
        return b;
@@ -457,7 +538,7 @@ static unsigned int hc_entries(unsigned int cnt)
        return cnt < avail_tree_table_sz ? cnt : avail_tree_table_sz - 1;
 }
 
-static struct tree_contentnew_tree_content(unsigned int cnt)
+static struct tree_content *new_tree_content(unsigned int cnt)
 {
        struct avail_tree_content *f, *l = NULL;
        struct tree_content *t;
@@ -480,6 +561,7 @@ static struct tree_content* new_tree_content(unsigned int cnt)
 
        t = (struct tree_content*)f;
        t->entry_count = 0;
+       t->delta_depth = 0;
        return t;
 }
 
@@ -500,28 +582,31 @@ static void release_tree_content_recursive(struct tree_content *t)
        release_tree_content(t);
 }
 
-static struct tree_contentgrow_tree_content(
+static struct tree_content *grow_tree_content(
        struct tree_content *t,
        int amt)
 {
        struct tree_content *r = new_tree_content(t->entry_count + amt);
        r->entry_count = t->entry_count;
+       r->delta_depth = t->delta_depth;
        memcpy(r->entries,t->entries,t->entry_count*sizeof(t->entries[0]));
        release_tree_content(t);
        return r;
 }
 
-static struct tree_entry* new_tree_entry()
+static struct tree_entry *new_tree_entry(void)
 {
        struct tree_entry *e;
 
        if (!avail_tree_entry) {
                unsigned int n = tree_entry_alloc;
+               total_allocd += n * sizeof(struct tree_entry);
                avail_tree_entry = e = xmalloc(n * sizeof(struct tree_entry));
-               while (n--) {
+               while (n-- > 1) {
                        *((void**)e) = e + 1;
                        e++;
                }
+               *((void**)e) = NULL;
        }
 
        e = avail_tree_entry;
@@ -537,30 +622,232 @@ static void release_tree_entry(struct tree_entry *e)
        avail_tree_entry = e;
 }
 
-static void yread(int fd, void *buffer, size_t length)
+static void start_packfile(void)
+{
+       static char tmpfile[PATH_MAX];
+       struct packed_git *p;
+       struct pack_header hdr;
+       int pack_fd;
+
+       snprintf(tmpfile, sizeof(tmpfile),
+               "%s/tmp_pack_XXXXXX", get_object_directory());
+       pack_fd = mkstemp(tmpfile);
+       if (pack_fd < 0)
+               die("Can't create %s: %s", tmpfile, strerror(errno));
+       p = xcalloc(1, sizeof(*p) + strlen(tmpfile) + 2);
+       strcpy(p->pack_name, tmpfile);
+       p->pack_fd = pack_fd;
+
+       hdr.hdr_signature = htonl(PACK_SIGNATURE);
+       hdr.hdr_version = htonl(2);
+       hdr.hdr_entries = 0;
+       write_or_die(p->pack_fd, &hdr, sizeof(hdr));
+
+       pack_data = p;
+       pack_size = sizeof(hdr);
+       object_count = 0;
+
+       all_packs = xrealloc(all_packs, sizeof(*all_packs) * (pack_id + 1));
+       all_packs[pack_id] = p;
+}
+
+static void fixup_header_footer(void)
+{
+       static const int buf_sz = 128 * 1024;
+       int pack_fd = pack_data->pack_fd;
+       SHA_CTX c;
+       struct pack_header hdr;
+       char *buf;
+
+       if (lseek(pack_fd, 0, SEEK_SET) != 0)
+               die("Failed seeking to start: %s", strerror(errno));
+       if (read_in_full(pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
+               die("Unable to reread header of %s", pack_data->pack_name);
+       if (lseek(pack_fd, 0, SEEK_SET) != 0)
+               die("Failed seeking to start: %s", strerror(errno));
+       hdr.hdr_entries = htonl(object_count);
+       write_or_die(pack_fd, &hdr, sizeof(hdr));
+
+       SHA1_Init(&c);
+       SHA1_Update(&c, &hdr, sizeof(hdr));
+
+       buf = xmalloc(buf_sz);
+       for (;;) {
+               size_t n = xread(pack_fd, buf, buf_sz);
+               if (!n)
+                       break;
+               if (n < 0)
+                       die("Failed to checksum %s", pack_data->pack_name);
+               SHA1_Update(&c, buf, n);
+       }
+       free(buf);
+
+       SHA1_Final(pack_data->sha1, &c);
+       write_or_die(pack_fd, pack_data->sha1, sizeof(pack_data->sha1));
+       close(pack_fd);
+}
+
+static int oecmp (const void *a_, const void *b_)
+{
+       struct object_entry *a = *((struct object_entry**)a_);
+       struct object_entry *b = *((struct object_entry**)b_);
+       return hashcmp(a->sha1, b->sha1);
+}
+
+static char *create_index(void)
 {
-       ssize_t ret = 0;
-       while (ret < length) {
-               ssize_t size = xread(fd, (char *) buffer + ret, length - ret);
-               if (!size)
-                       die("Read from descriptor %i: end of stream", fd);
-               if (size < 0)
-                       die("Read from descriptor %i: %s", fd, strerror(errno));
-               ret += size;
+       static char tmpfile[PATH_MAX];
+       SHA_CTX ctx;
+       struct sha1file *f;
+       struct object_entry **idx, **c, **last, *e;
+       struct object_entry_pool *o;
+       uint32_t array[256];
+       int i, idx_fd;
+
+       /* Build the sorted table of object IDs. */
+       idx = xmalloc(object_count * sizeof(struct object_entry*));
+       c = idx;
+       for (o = blocks; o; o = o->next_pool)
+               for (e = o->next_free; e-- != o->entries;)
+                       if (pack_id == e->pack_id)
+                               *c++ = e;
+       last = idx + object_count;
+       if (c != last)
+               die("internal consistency error creating the index");
+       qsort(idx, object_count, sizeof(struct object_entry*), oecmp);
+
+       /* Generate the fan-out array. */
+       c = idx;
+       for (i = 0; i < 256; i++) {
+               struct object_entry **next = c;;
+               while (next < last) {
+                       if ((*next)->sha1[0] != i)
+                               break;
+                       next++;
+               }
+               array[i] = htonl(next - idx);
+               c = next;
+       }
+
+       snprintf(tmpfile, sizeof(tmpfile),
+               "%s/tmp_idx_XXXXXX", get_object_directory());
+       idx_fd = mkstemp(tmpfile);
+       if (idx_fd < 0)
+               die("Can't create %s: %s", tmpfile, strerror(errno));
+       f = sha1fd(idx_fd, tmpfile);
+       sha1write(f, array, 256 * sizeof(int));
+       SHA1_Init(&ctx);
+       for (c = idx; c != last; c++) {
+               uint32_t offset = htonl((*c)->offset);
+               sha1write(f, &offset, 4);
+               sha1write(f, (*c)->sha1, sizeof((*c)->sha1));
+               SHA1_Update(&ctx, (*c)->sha1, 20);
        }
+       sha1write(f, pack_data->sha1, sizeof(pack_data->sha1));
+       sha1close(f, NULL, 1);
+       free(idx);
+       SHA1_Final(pack_data->sha1, &ctx);
+       return tmpfile;
+}
+
+static char *keep_pack(char *curr_index_name)
+{
+       static char name[PATH_MAX];
+       static const char *keep_msg = "fast-import";
+       int keep_fd;
+
+       chmod(pack_data->pack_name, 0444);
+       chmod(curr_index_name, 0444);
+
+       snprintf(name, sizeof(name), "%s/pack/pack-%s.keep",
+                get_object_directory(), sha1_to_hex(pack_data->sha1));
+       keep_fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
+       if (keep_fd < 0)
+               die("cannot create keep file");
+       write(keep_fd, keep_msg, strlen(keep_msg));
+       close(keep_fd);
+
+       snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
+                get_object_directory(), sha1_to_hex(pack_data->sha1));
+       if (move_temp_to_file(pack_data->pack_name, name))
+               die("cannot store pack file");
+
+       snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
+                get_object_directory(), sha1_to_hex(pack_data->sha1));
+       if (move_temp_to_file(curr_index_name, name))
+               die("cannot store index file");
+       return name;
 }
 
-static void ywrite(int fd, void *buffer, size_t length)
+static void unkeep_all_packs(void)
 {
-       ssize_t ret = 0;
-       while (ret < length) {
-               ssize_t size = xwrite(fd, (char *) buffer + ret, length - ret);
-               if (!size)
-                       die("Write to descriptor %i: end of file", fd);
-               if (size < 0)
-                       die("Write to descriptor %i: %s", fd, strerror(errno));
-               ret += size;
+       static char name[PATH_MAX];
+       int k;
+
+       for (k = 0; k < pack_id; k++) {
+               struct packed_git *p = all_packs[k];
+               snprintf(name, sizeof(name), "%s/pack/pack-%s.keep",
+                        get_object_directory(), sha1_to_hex(p->sha1));
+               unlink(name);
+       }
+}
+
+static void end_packfile(void)
+{
+       struct packed_git *old_p = pack_data, *new_p;
+
+       if (object_count) {
+               char *idx_name;
+               int i;
+               struct branch *b;
+               struct tag *t;
+
+               fixup_header_footer();
+               idx_name = keep_pack(create_index());
+
+               /* Register the packfile with core git's machinary. */
+               new_p = add_packed_git(idx_name, strlen(idx_name), 1);
+               if (!new_p)
+                       die("core git rejected index %s", idx_name);
+               new_p->windows = old_p->windows;
+               all_packs[pack_id] = new_p;
+               install_packed_git(new_p);
+
+               /* Print the boundary */
+               if (pack_edges) {
+                       fprintf(pack_edges, "%s:", new_p->pack_name);
+                       for (i = 0; i < branch_table_sz; i++) {
+                               for (b = branch_table[i]; b; b = b->table_next_branch) {
+                                       if (b->pack_id == pack_id)
+                                               fprintf(pack_edges, " %s", sha1_to_hex(b->sha1));
+                               }
+                       }
+                       for (t = first_tag; t; t = t->next_tag) {
+                               if (t->pack_id == pack_id)
+                                       fprintf(pack_edges, " %s", sha1_to_hex(t->sha1));
+                       }
+                       fputc('\n', pack_edges);
+                       fflush(pack_edges);
+               }
+
+               pack_id++;
        }
+       else
+               unlink(old_p->pack_name);
+       free(old_p);
+
+       /* We can't carry a delta across packfiles. */
+       free(last_blob.data);
+       last_blob.data = NULL;
+       last_blob.len = 0;
+       last_blob.offset = 0;
+       last_blob.depth = 0;
+}
+
+static void cycle_packfile(void)
+{
+       end_packfile();
+       start_packfile();
 }
 
 static size_t encode_header(
@@ -571,7 +858,7 @@ static size_t encode_header(
        int n = 1;
        unsigned char c;
 
-       if (type < OBJ_COMMIT || type > OBJ_DELTA)
+       if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
                die("bad type %d", type);
 
        c = (type << 4) | (size & 15);
@@ -592,7 +879,7 @@ static int store_object(
        size_t datlen,
        struct last_object *last,
        unsigned char *sha1out,
-       unsigned long mark)
+       uintmax_t mark)
 {
        void *out, *delta;
        struct object_entry *e;
@@ -602,202 +889,134 @@ static int store_object(
        SHA_CTX c;
        z_stream s;
 
-       hdrlen = sprintf((char*)hdr,"%s %lu",type_names[type],datlen) + 1;
+       hdrlen = sprintf((char*)hdr,"%s %lu", typename(type),
+               (unsigned long)datlen) + 1;
        SHA1_Init(&c);
        SHA1_Update(&c, hdr, hdrlen);
        SHA1_Update(&c, dat, datlen);
        SHA1_Final(sha1, &c);
        if (sha1out)
-               memcpy(sha1out, sha1, sizeof(sha1));
+               hashcpy(sha1out, sha1);
 
        e = insert_object(sha1);
        if (mark)
                insert_mark(mark, e);
        if (e->offset) {
-               duplicate_count++;
                duplicate_count_by_type[type]++;
                return 1;
        }
-       e->type = type;
-       e->offset = pack_size;
-       object_count++;
-       object_count_by_type[type]++;
 
-       if (last && last->data && last->depth < max_depth)
+       if (last && last->data && last->depth < max_depth) {
                delta = diff_delta(last->data, last->len,
                        dat, datlen,
                        &deltalen, 0);
-       else
-               delta = 0;
+               if (delta && deltalen >= datlen) {
+                       free(delta);
+                       delta = NULL;
+               }
+       } else
+               delta = NULL;
 
        memset(&s, 0, sizeof(s));
        deflateInit(&s, zlib_compression_level);
-
        if (delta) {
-               last->depth++;
                s.next_in = delta;
                s.avail_in = deltalen;
-               hdrlen = encode_header(OBJ_DELTA, deltalen, hdr);
-               ywrite(pack_fd, hdr, hdrlen);
-               ywrite(pack_fd, last->sha1, sizeof(sha1));
-               pack_size += hdrlen + sizeof(sha1);
        } else {
-               if (last)
-                       last->depth = 0;
                s.next_in = dat;
                s.avail_in = datlen;
-               hdrlen = encode_header(type, datlen, hdr);
-               ywrite(pack_fd, hdr, hdrlen);
-               pack_size += hdrlen;
        }
-
        s.avail_out = deflateBound(&s, s.avail_in);
        s.next_out = out = xmalloc(s.avail_out);
        while (deflate(&s, Z_FINISH) == Z_OK)
                /* nothing */;
        deflateEnd(&s);
 
-       ywrite(pack_fd, out, s.total_out);
-       pack_size += s.total_out;
-
-       free(out);
-       if (delta)
-               free(delta);
-       if (last) {
-               if (last->data)
-                       free(last->data);
-               last->data = dat;
-               last->len = datlen;
-               memcpy(last->sha1, sha1, sizeof(sha1));
+       /* Determine if we should auto-checkpoint. */
+       if ((pack_size + 60 + s.total_out) > max_packsize
+               || (pack_size + 60 + s.total_out) < pack_size) {
+
+               /* This new object needs to *not* have the current pack_id. */
+               e->pack_id = pack_id + 1;
+               cycle_packfile();
+
+               /* We cannot carry a delta into the new pack. */
+               if (delta) {
+                       free(delta);
+                       delta = NULL;
+
+                       memset(&s, 0, sizeof(s));
+                       deflateInit(&s, zlib_compression_level);
+                       s.next_in = dat;
+                       s.avail_in = datlen;
+                       s.avail_out = deflateBound(&s, s.avail_in);
+                       s.next_out = out = xrealloc(out, s.avail_out);
+                       while (deflate(&s, Z_FINISH) == Z_OK)
+                               /* nothing */;
+                       deflateEnd(&s);
+               }
        }
-       return 0;
-}
 
-static void* map_pack(unsigned long offset)
-{
-       if (offset >= pack_size)
-               die("object offset outside of pack file");
-       if (offset >= pack_mlen) {
-               if (pack_base)
-                       munmap(pack_base, pack_mlen);
-               /* round out how much we map to 16 MB units */
-               pack_mlen = pack_size;
-               if (pack_mlen & ((1 << 24) - 1))
-                       pack_mlen = ((pack_mlen >> 24) + 1) << 24;
-               pack_base = mmap(NULL,pack_mlen,PROT_READ,MAP_SHARED,pack_fd,0);
-               if (pack_base == MAP_FAILED)
-                       die("Failed to map generated pack: %s", strerror(errno));
-               remap_count++;
-       }
-       return (char*)pack_base + offset;
-}
+       e->type = type;
+       e->pack_id = pack_id;
+       e->offset = pack_size;
+       object_count++;
+       object_count_by_type[type]++;
 
-static unsigned long unpack_object_header(unsigned long offset,
-       enum object_type *type,
-       unsigned long *sizep)
-{
-       unsigned shift;
-       unsigned char c;
-       unsigned long size;
+       if (delta) {
+               unsigned long ofs = e->offset - last->offset;
+               unsigned pos = sizeof(hdr) - 1;
 
-       c = *(unsigned char*)map_pack(offset++);
-       *type = (c >> 4) & 7;
-       size = c & 15;
-       shift = 4;
-       while (c & 0x80) {
-               c = *(unsigned char*)map_pack(offset++);
-               size += (c & 0x7f) << shift;
-               shift += 7;
-       }
-       *sizep = size;
-       return offset;
-}
+               delta_count_by_type[type]++;
+               last->depth++;
 
-static void *unpack_non_delta_entry(unsigned long o, unsigned long sz)
-{
-       z_stream stream;
-       unsigned char *result;
+               hdrlen = encode_header(OBJ_OFS_DELTA, deltalen, hdr);
+               write_or_die(pack_data->pack_fd, hdr, hdrlen);
+               pack_size += hdrlen;
 
-       result = xmalloc(sz + 1);
-       result[sz] = 0;
+               hdr[pos] = ofs & 127;
+               while (ofs >>= 7)
+                       hdr[--pos] = 128 | (--ofs & 127);
+               write_or_die(pack_data->pack_fd, hdr + pos, sizeof(hdr) - pos);
+               pack_size += sizeof(hdr) - pos;
+       } else {
+               if (last)
+                       last->depth = 0;
+               hdrlen = encode_header(type, datlen, hdr);
+               write_or_die(pack_data->pack_fd, hdr, hdrlen);
+               pack_size += hdrlen;
+       }
 
-       memset(&stream, 0, sizeof(stream));
-       stream.next_in = map_pack(o);
-       stream.avail_in = pack_mlen - o;
-       stream.next_out = result;
-       stream.avail_out = sz;
+       write_or_die(pack_data->pack_fd, out, s.total_out);
+       pack_size += s.total_out;
 
-       inflateInit(&stream);
-       for (;;) {
-               int st = inflate(&stream, Z_FINISH);
-               if (st == Z_STREAM_END)
-                       break;
-               if (st == Z_OK) {
-                       o = stream.next_in - (unsigned char*)pack_base;
-                       stream.next_in = map_pack(o);
-                       stream.avail_in = pack_mlen - o;
-                       continue;
-               }
-               die("Error from zlib during inflate.");
+       free(out);
+       free(delta);
+       if (last) {
+               if (!last->no_free)
+                       free(last->data);
+               last->data = dat;
+               last->offset = e->offset;
+               last->len = datlen;
        }
-       inflateEnd(&stream);
-       if (stream.total_out != sz)
-               die("Error after inflate: sizes mismatch");
-       return result;
+       return 0;
 }
 
-static void *unpack_entry(unsigned long offset, unsigned long *sizep);
-
-static void *unpack_delta_entry(unsigned long offset,
-       unsigned long delta_size,
+static void *gfi_unpack_entry(
+       struct object_entry *oe,
        unsigned long *sizep)
 {
-       struct object_entry *base_oe;
-       unsigned char *base_sha1;
-       void *delta_data, *base, *result;
-       unsigned long base_size, result_size;
-
-       base_sha1 = (unsigned char*)map_pack(offset + 20) - 20;
-       base_oe = find_object(base_sha1);
-       if (!base_oe)
-               die("I'm broken; I can't find a base I know must be here.");
-       base = unpack_entry(base_oe->offset, &base_size);
-       delta_data = unpack_non_delta_entry(offset + 20, delta_size);
-       result = patch_delta(base, base_size,
-                            delta_data, delta_size,
-                            &result_size);
-       if (!result)
-               die("failed to apply delta");
-       free(delta_data);
-       free(base);
-       *sizep = result_size;
-       return result;
-}
-
-static void *unpack_entry(unsigned long offset, unsigned long *sizep)
-{
-       unsigned long size;
-       enum object_type kind;
-
-       offset = unpack_object_header(offset, &kind, &size);
-       switch (kind) {
-       case OBJ_DELTA:
-               return unpack_delta_entry(offset, size, sizep);
-       case OBJ_COMMIT:
-       case OBJ_TREE:
-       case OBJ_BLOB:
-       case OBJ_TAG:
-               *sizep = size;
-               return unpack_non_delta_entry(offset, size);
-       default:
-               die("I created an object I can't read!");
-       }
+       enum object_type type;
+       struct packed_git *p = all_packs[oe->pack_id];
+       if (p == pack_data)
+               p->pack_size = pack_size + 20;
+       return unpack_entry(p, oe->offset, &type, sizep);
 }
 
-static const char *get_mode(const char *str, unsigned int *modep)
+static const char *get_mode(const char *str, uint16_t *modep)
 {
        unsigned char c;
-       unsigned int mode = 0;
+       uint16_t mode = 0;
 
        while ((c = *str++) != ' ') {
                if (c < '0' || c > '7')
@@ -810,6 +1029,7 @@ static const char *get_mode(const char *str, unsigned int *modep)
 
 static void load_tree(struct tree_entry *root)
 {
+       unsigned char* sha1 = root->versions[1].sha1;
        struct object_entry *myoe;
        struct tree_content *t;
        unsigned long size;
@@ -817,19 +1037,20 @@ static void load_tree(struct tree_entry *root)
        const char *c;
 
        root->tree = t = new_tree_content(8);
-       if (!memcmp(root->sha1, null_sha1, 20))
+       if (is_null_sha1(sha1))
                return;
 
-       myoe = find_object(root->sha1);
+       myoe = find_object(sha1);
        if (myoe) {
                if (myoe->type != OBJ_TREE)
-                       die("Not a tree: %s", sha1_to_hex(root->sha1));
-               buf = unpack_entry(myoe->offset, &size);
+                       die("Not a tree: %s", sha1_to_hex(sha1));
+               t->delta_depth = 0;
+               buf = gfi_unpack_entry(myoe, &size);
        } else {
-               char type[20];
-               buf = read_sha1_file(root->sha1, type, &size);
-               if (!buf || !strcmp(type, tree_type))
-                       die("Can't load tree %s", sha1_to_hex(root->sha1));
+               enum object_type type;
+               buf = read_sha1_file(sha1, &type, &size);
+               if (!buf || type != OBJ_TREE)
+                       die("Can't load tree %s", sha1_to_hex(sha1));
        }
 
        c = buf;
@@ -837,67 +1058,130 @@ static void load_tree(struct tree_entry *root)
                struct tree_entry *e = new_tree_entry();
 
                if (t->entry_count == t->entry_capacity)
-                       root->tree = t = grow_tree_content(t, 8);
+                       root->tree = t = grow_tree_content(t, t->entry_count);
                t->entries[t->entry_count++] = e;
 
                e->tree = NULL;
-               c = get_mode(c, &e->mode);
+               c = get_mode(c, &e->versions[1].mode);
                if (!c)
-                       die("Corrupt mode in %s", sha1_to_hex(root->sha1));
+                       die("Corrupt mode in %s", sha1_to_hex(sha1));
+               e->versions[0].mode = e->versions[1].mode;
                e->name = to_atom(c, strlen(c));
                c += e->name->str_len + 1;
-               memcpy(e->sha1, c, sizeof(e->sha1));
+               hashcpy(e->versions[0].sha1, (unsigned char*)c);
+               hashcpy(e->versions[1].sha1, (unsigned char*)c);
                c += 20;
        }
        free(buf);
 }
 
-static int tecmp (const void *_a, const void *_b)
+static int tecmp0 (const void *_a, const void *_b)
 {
        struct tree_entry *a = *((struct tree_entry**)_a);
        struct tree_entry *b = *((struct tree_entry**)_b);
        return base_name_compare(
-               a->name->str_dat, a->name->str_len, a->mode,
-               b->name->str_dat, b->name->str_len, b->mode);
+               a->name->str_dat, a->name->str_len, a->versions[0].mode,
+               b->name->str_dat, b->name->str_len, b->versions[0].mode);
 }
 
-static void store_tree(struct tree_entry *root)
+static int tecmp1 (const void *_a, const void *_b)
 {
-       struct tree_content *t = root->tree;
+       struct tree_entry *a = *((struct tree_entry**)_a);
+       struct tree_entry *b = *((struct tree_entry**)_b);
+       return base_name_compare(
+               a->name->str_dat, a->name->str_len, a->versions[1].mode,
+               b->name->str_dat, b->name->str_len, b->versions[1].mode);
+}
+
+static void mktree(struct tree_content *t,
+       int v,
+       unsigned long *szp,
+       struct dbuf *b)
+{
+       size_t maxlen = 0;
        unsigned int i;
-       size_t maxlen;
-       char *buf, *c;
+       char *c;
 
-       if (memcmp(root->sha1, null_sha1, 20))
-               return;
+       if (!v)
+               qsort(t->entries,t->entry_count,sizeof(t->entries[0]),tecmp0);
+       else
+               qsort(t->entries,t->entry_count,sizeof(t->entries[0]),tecmp1);
 
-       maxlen = 0;
        for (i = 0; i < t->entry_count; i++) {
-               maxlen += t->entries[i]->name->str_len + 34;
-               if (t->entries[i]->tree)
-                       store_tree(t->entries[i]);
+               if (t->entries[i]->versions[v].mode)
+                       maxlen += t->entries[i]->name->str_len + 34;
        }
 
-       qsort(t->entries, t->entry_count, sizeof(t->entries[0]), tecmp);
-       buf = c = xmalloc(maxlen);
+       size_dbuf(b, maxlen);
+       c = b->buffer;
        for (i = 0; i < t->entry_count; i++) {
                struct tree_entry *e = t->entries[i];
-               c += sprintf(c, "%o", e->mode);
+               if (!e->versions[v].mode)
+                       continue;
+               c += sprintf(c, "%o", (unsigned int)e->versions[v].mode);
                *c++ = ' ';
                strcpy(c, e->name->str_dat);
                c += e->name->str_len + 1;
-               memcpy(c, e->sha1, 20);
+               hashcpy((unsigned char*)c, e->versions[v].sha1);
                c += 20;
        }
-       store_object(OBJ_TREE, buf, c - buf, NULL, root->sha1, 0);
-       free(buf);
+       *szp = c - (char*)b->buffer;
+}
+
+static void store_tree(struct tree_entry *root)
+{
+       struct tree_content *t = root->tree;
+       unsigned int i, j, del;
+       unsigned long new_len;
+       struct last_object lo;
+       struct object_entry *le;
+
+       if (!is_null_sha1(root->versions[1].sha1))
+               return;
+
+       for (i = 0; i < t->entry_count; i++) {
+               if (t->entries[i]->tree)
+                       store_tree(t->entries[i]);
+       }
+
+       le = find_object(root->versions[0].sha1);
+       if (!S_ISDIR(root->versions[0].mode)
+               || !le
+               || le->pack_id != pack_id) {
+               lo.data = NULL;
+               lo.depth = 0;
+       } else {
+               mktree(t, 0, &lo.len, &old_tree);
+               lo.data = old_tree.buffer;
+               lo.offset = le->offset;
+               lo.depth = t->delta_depth;
+               lo.no_free = 1;
+       }
+
+       mktree(t, 1, &new_len, &new_tree);
+       store_object(OBJ_TREE, new_tree.buffer, new_len,
+               &lo, root->versions[1].sha1, 0);
+
+       t->delta_depth = lo.depth;
+       for (i = 0, j = 0, del = 0; i < t->entry_count; i++) {
+               struct tree_entry *e = t->entries[i];
+               if (e->versions[1].mode) {
+                       e->versions[0].mode = e->versions[1].mode;
+                       hashcpy(e->versions[0].sha1, e->versions[1].sha1);
+                       t->entries[j++] = e;
+               } else {
+                       release_tree_entry(e);
+                       del++;
+               }
+       }
+       t->entry_count -= del;
 }
 
 static int tree_content_set(
        struct tree_entry *root,
        const char *p,
        const unsigned char *sha1,
-       const unsigned int mode)
+       const uint16_t mode)
 {
        struct tree_content *t = root->tree;
        const char *slash1;
@@ -914,25 +1198,26 @@ static int tree_content_set(
                e = t->entries[i];
                if (e->name->str_len == n && !strncmp(p, e->name->str_dat, n)) {
                        if (!slash1) {
-                               if (e->mode == mode && !memcmp(e->sha1, sha1, 20))
+                               if (e->versions[1].mode == mode
+                                               && !hashcmp(e->versions[1].sha1, sha1))
                                        return 0;
-                               e->mode = mode;
-                               memcpy(e->sha1, sha1, 20);
+                               e->versions[1].mode = mode;
+                               hashcpy(e->versions[1].sha1, sha1);
                                if (e->tree) {
                                        release_tree_content_recursive(e->tree);
                                        e->tree = NULL;
                                }
-                               memcpy(root->sha1, null_sha1, 20);
+                               hashclr(root->versions[1].sha1);
                                return 1;
                        }
-                       if (!S_ISDIR(e->mode)) {
+                       if (!S_ISDIR(e->versions[1].mode)) {
                                e->tree = new_tree_content(8);
-                               e->mode = S_IFDIR;
+                               e->versions[1].mode = S_IFDIR;
                        }
                        if (!e->tree)
                                load_tree(e);
                        if (tree_content_set(e, slash1 + 1, sha1, mode)) {
-                               memcpy(root->sha1, null_sha1, 20);
+                               hashclr(root->versions[1].sha1);
                                return 1;
                        }
                        return 0;
@@ -940,20 +1225,22 @@ static int tree_content_set(
        }
 
        if (t->entry_count == t->entry_capacity)
-               root->tree = t = grow_tree_content(t, 8);
+               root->tree = t = grow_tree_content(t, t->entry_count);
        e = new_tree_entry();
        e->name = to_atom(p, n);
+       e->versions[0].mode = 0;
+       hashclr(e->versions[0].sha1);
        t->entries[t->entry_count++] = e;
        if (slash1) {
                e->tree = new_tree_content(8);
-               e->mode = S_IFDIR;
+               e->versions[1].mode = S_IFDIR;
                tree_content_set(e, slash1 + 1, sha1, mode);
        } else {
                e->tree = NULL;
-               e->mode = mode;
-               memcpy(e->sha1, sha1, 20);
+               e->versions[1].mode = mode;
+               hashcpy(e->versions[1].sha1, sha1);
        }
-       memcpy(root->sha1, null_sha1, 20);
+       hashclr(root->versions[1].sha1);
        return 1;
 }
 
@@ -973,15 +1260,18 @@ static int tree_content_remove(struct tree_entry *root, const char *p)
        for (i = 0; i < t->entry_count; i++) {
                e = t->entries[i];
                if (e->name->str_len == n && !strncmp(p, e->name->str_dat, n)) {
-                       if (!slash1 || !S_ISDIR(e->mode))
+                       if (!slash1 || !S_ISDIR(e->versions[1].mode))
                                goto del_entry;
                        if (!e->tree)
                                load_tree(e);
                        if (tree_content_remove(e, slash1 + 1)) {
-                               if (!e->tree->entry_count)
-                                       goto del_entry;
-                               memcpy(root->sha1, null_sha1, 20);
-                               return 1;
+                               for (n = 0; n < e->tree->entry_count; n++) {
+                                       if (e->tree->entries[n]->versions[1].mode) {
+                                               hashclr(root->versions[1].sha1);
+                                               return 1;
+                                       }
+                               }
+                               goto del_entry;
                        }
                        return 0;
                }
@@ -989,171 +1279,187 @@ static int tree_content_remove(struct tree_entry *root, const char *p)
        return 0;
 
 del_entry:
-       for (i++; i < t->entry_count; i++)
-               t->entries[i-1] = t->entries[i];
-       t->entry_count--;
-       release_tree_entry(e);
-       memcpy(root->sha1, null_sha1, 20);
-       return 1;
-}
-
-static void init_pack_header()
-{
-       struct pack_header hdr;
-
-       hdr.hdr_signature = htonl(PACK_SIGNATURE);
-       hdr.hdr_version = htonl(2);
-       hdr.hdr_entries = 0;
-
-       ywrite(pack_fd, &hdr, sizeof(hdr));
-       pack_size = sizeof(hdr);
-}
-
-static void fixup_header_footer()
-{
-       SHA_CTX c;
-       char hdr[8];
-       unsigned long cnt;
-       char *buf;
-       size_t n;
-
-       if (lseek(pack_fd, 0, SEEK_SET) != 0)
-               die("Failed seeking to start: %s", strerror(errno));
-
-       SHA1_Init(&c);
-       yread(pack_fd, hdr, 8);
-       SHA1_Update(&c, hdr, 8);
-
-       cnt = htonl(object_count);
-       SHA1_Update(&c, &cnt, 4);
-       ywrite(pack_fd, &cnt, 4);
-
-       buf = xmalloc(128 * 1024);
-       for (;;) {
-               n = xread(pack_fd, buf, 128 * 1024);
-               if (n <= 0)
-                       break;
-               SHA1_Update(&c, buf, n);
+       if (e->tree) {
+               release_tree_content_recursive(e->tree);
+               e->tree = NULL;
        }
-       free(buf);
-
-       SHA1_Final(pack_sha1, &c);
-       ywrite(pack_fd, pack_sha1, sizeof(pack_sha1));
-}
-
-static int oecmp (const void *_a, const void *_b)
-{
-       struct object_entry *a = *((struct object_entry**)_a);
-       struct object_entry *b = *((struct object_entry**)_b);
-       return memcmp(a->sha1, b->sha1, sizeof(a->sha1));
+       e->versions[1].mode = 0;
+       hashclr(e->versions[1].sha1);
+       hashclr(root->versions[1].sha1);
+       return 1;
 }
 
-static void write_index(const char *idx_name)
+static int update_branch(struct branch *b)
 {
-       struct sha1file *f;
-       struct object_entry **idx, **c, **last;
-       struct object_entry *e;
-       struct object_entry_pool *o;
-       unsigned int array[256];
-       int i;
-
-       /* Build the sorted table of object IDs. */
-       idx = xmalloc(object_count * sizeof(struct object_entry*));
-       c = idx;
-       for (o = blocks; o; o = o->next_pool)
-               for (e = o->entries; e != o->next_free; e++)
-                       *c++ = e;
-       last = idx + object_count;
-       qsort(idx, object_count, sizeof(struct object_entry*), oecmp);
-
-       /* Generate the fan-out array. */
-       c = idx;
-       for (i = 0; i < 256; i++) {
-               struct object_entry **next = c;;
-               while (next < last) {
-                       if ((*next)->sha1[0] != i)
-                               break;
-                       next++;
+       static const char *msg = "fast-import";
+       struct ref_lock *lock;
+       unsigned char old_sha1[20];
+
+       if (read_ref(b->name, old_sha1))
+               hashclr(old_sha1);
+       lock = lock_any_ref_for_update(b->name, old_sha1);
+       if (!lock)
+               return error("Unable to lock %s", b->name);
+       if (!force_update && !is_null_sha1(old_sha1)) {
+               struct commit *old_cmit, *new_cmit;
+
+               old_cmit = lookup_commit_reference_gently(old_sha1, 0);
+               new_cmit = lookup_commit_reference_gently(b->sha1, 0);
+               if (!old_cmit || !new_cmit) {
+                       unlock_ref(lock);
+                       return error("Branch %s is missing commits.", b->name);
                }
-               array[i] = htonl(next - idx);
-               c = next;
-       }
 
-       f = sha1create("%s", idx_name);
-       sha1write(f, array, 256 * sizeof(int));
-       for (c = idx; c != last; c++) {
-               unsigned int offset = htonl((*c)->offset);
-               sha1write(f, &offset, 4);
-               sha1write(f, (*c)->sha1, sizeof((*c)->sha1));
+               if (!in_merge_bases(old_cmit, &new_cmit, 1)) {
+                       unlock_ref(lock);
+                       warning("Not updating %s"
+                               " (new tip %s does not contain %s)",
+                               b->name, sha1_to_hex(b->sha1), sha1_to_hex(old_sha1));
+                       return -1;
+               }
        }
-       sha1write(f, pack_sha1, sizeof(pack_sha1));
-       sha1close(f, NULL, 1);
-       free(idx);
+       if (write_ref_sha1(lock, b->sha1, msg) < 0)
+               return error("Unable to update %s", b->name);
+       return 0;
 }
 
-static void dump_branches()
+static void dump_branches(void)
 {
-       static const char *msg = "fast-import";
        unsigned int i;
        struct branch *b;
-       struct ref_lock *lock;
 
        for (i = 0; i < branch_table_sz; i++) {
-               for (b = branch_table[i]; b; b = b->table_next_branch) {
-                       lock = lock_any_ref_for_update(b->name, NULL, 0);
-                       if (!lock || write_ref_sha1(lock, b->sha1, msg) < 0)
-                               die("Can't write %s", b->name);
-               }
+               for (b = branch_table[i]; b; b = b->table_next_branch)
+                       failure |= update_branch(b);
        }
 }
 
-static void dump_tags()
+static void dump_tags(void)
 {
        static const char *msg = "fast-import";
        struct tag *t;
        struct ref_lock *lock;
-       char path[PATH_MAX];
+       char ref_name[PATH_MAX];
 
        for (t = first_tag; t; t = t->next_tag) {
-               sprintf(path, "refs/tags/%s", t->name);
-               lock = lock_any_ref_for_update(path, NULL, 0);
+               sprintf(ref_name, "tags/%s", t->name);
+               lock = lock_ref_sha1(ref_name, NULL);
                if (!lock || write_ref_sha1(lock, t->sha1, msg) < 0)
-                       die("Can't write %s", path);
+                       failure |= error("Unable to update %s", ref_name);
+       }
+}
+
+static void dump_marks_helper(FILE *f,
+       uintmax_t base,
+       struct mark_set *m)
+{
+       uintmax_t k;
+       if (m->shift) {
+               for (k = 0; k < 1024; k++) {
+                       if (m->data.sets[k])
+                               dump_marks_helper(f, (base + k) << m->shift,
+                                       m->data.sets[k]);
+               }
+       } else {
+               for (k = 0; k < 1024; k++) {
+                       if (m->data.marked[k])
+                               fprintf(f, ":%" PRIuMAX " %s\n", base + k,
+                                       sha1_to_hex(m->data.marked[k]->sha1));
+               }
+       }
+}
+
+static void dump_marks(void)
+{
+       static struct lock_file mark_lock;
+       int mark_fd;
+       FILE *f;
+
+       if (!mark_file)
+               return;
+
+       mark_fd = hold_lock_file_for_update(&mark_lock, mark_file, 0);
+       if (mark_fd < 0) {
+               failure |= error("Unable to write marks file %s: %s",
+                       mark_file, strerror(errno));
+               return;
+       }
+
+       f = fdopen(mark_fd, "w");
+       if (!f) {
+               rollback_lock_file(&mark_lock);
+               failure |= error("Unable to write marks file %s: %s",
+                       mark_file, strerror(errno));
+               return;
        }
+
+       dump_marks_helper(f, 0, marks);
+       fclose(f);
+       if (commit_lock_file(&mark_lock))
+               failure |= error("Unable to write marks file %s: %s",
+                       mark_file, strerror(errno));
 }
 
-static void read_next_command()
+static void read_next_command(void)
 {
        read_line(&command_buf, stdin, '\n');
 }
 
-static void cmd_mark()
+static void cmd_mark(void)
 {
-       if (!strncmp("mark :", command_buf.buf, 6)) {
-               next_mark = strtoul(command_buf.buf + 6, NULL, 10);
+       if (!prefixcmp(command_buf.buf, "mark :")) {
+               next_mark = strtoumax(command_buf.buf + 6, NULL, 10);
                read_next_command();
        }
        else
                next_mark = 0;
 }
 
-static voidcmd_data (size_t *size)
+static void *cmd_data (size_t *size)
 {
-       size_t n = 0;
-       void *buffer;
        size_t length;
+       char *buffer;
 
-       if (strncmp("data ", command_buf.buf, 5))
+       if (prefixcmp(command_buf.buf, "data "))
                die("Expected 'data n' command, found: %s", command_buf.buf);
 
-       length = strtoul(command_buf.buf + 5, NULL, 10);
-       buffer = xmalloc(length);
-
-       while (n < length) {
-               size_t s = fread((char*)buffer + n, 1, length - n, stdin);
-               if (!s && feof(stdin))
-                       die("EOF in data (%lu bytes remaining)", length - n);
-               n += s;
+       if (!prefixcmp(command_buf.buf + 5, "<<")) {
+               char *term = xstrdup(command_buf.buf + 5 + 2);
+               size_t sz = 8192, term_len = command_buf.len - 5 - 2;
+               length = 0;
+               buffer = xmalloc(sz);
+               for (;;) {
+                       read_next_command();
+                       if (command_buf.eof)
+                               die("EOF in data (terminator '%s' not found)", term);
+                       if (term_len == command_buf.len
+                               && !strcmp(term, command_buf.buf))
+                               break;
+                       if (sz < (length + command_buf.len)) {
+                               sz = sz * 3 / 2 + 16;
+                               if (sz < (length + command_buf.len))
+                                       sz = length + command_buf.len;
+                               buffer = xrealloc(buffer, sz);
+                       }
+                       memcpy(buffer + length,
+                               command_buf.buf,
+                               command_buf.len - 1);
+                       length += command_buf.len - 1;
+                       buffer[length++] = '\n';
+               }
+               free(term);
+       }
+       else {
+               size_t n = 0;
+               length = strtoul(command_buf.buf + 5, NULL, 10);
+               buffer = xmalloc(length);
+               while (n < length) {
+                       size_t s = fread(buffer + n, 1, length - n, stdin);
+                       if (!s && feof(stdin))
+                               die("EOF in data (%lu bytes remaining)",
+                                       (unsigned long)(length - n));
+                       n += s;
+               }
        }
 
        if (fgetc(stdin) != '\n')
@@ -1163,7 +1469,65 @@ static void* cmd_data (size_t *size)
        return buffer;
 }
 
-static void cmd_new_blob()
+static int validate_raw_date(const char *src, char *result, int maxlen)
+{
+       const char *orig_src = src;
+       char *endp, sign;
+
+       strtoul(src, &endp, 10);
+       if (endp == src || *endp != ' ')
+               return -1;
+
+       src = endp + 1;
+       if (*src != '-' && *src != '+')
+               return -1;
+       sign = *src;
+
+       strtoul(src + 1, &endp, 10);
+       if (endp == src || *endp || (endp - orig_src) >= maxlen)
+               return -1;
+
+       strcpy(result, orig_src);
+       return 0;
+}
+
+static char *parse_ident(const char *buf)
+{
+       const char *gt;
+       size_t name_len;
+       char *ident;
+
+       gt = strrchr(buf, '>');
+       if (!gt)
+               die("Missing > in ident string: %s", buf);
+       gt++;
+       if (*gt != ' ')
+               die("Missing space after > in ident string: %s", buf);
+       gt++;
+       name_len = gt - buf;
+       ident = xmalloc(name_len + 24);
+       strncpy(ident, buf, name_len);
+
+       switch (whenspec) {
+       case WHENSPEC_RAW:
+               if (validate_raw_date(gt, ident + name_len, 24) < 0)
+                       die("Invalid raw date \"%s\" in ident: %s", gt, buf);
+               break;
+       case WHENSPEC_RFC2822:
+               if (parse_date(gt, ident + name_len, 24) < 0)
+                       die("Invalid rfc2822 date \"%s\" in ident: %s", gt, buf);
+               break;
+       case WHENSPEC_NOW:
+               if (strcmp("now", gt))
+                       die("Date in ident must be 'now': %s", buf);
+               datestamp(ident + name_len, 24);
+               break;
+       }
+
+       return ident;
+}
+
+static void cmd_new_blob(void)
 {
        size_t l;
        void *d;
@@ -1176,11 +1540,11 @@ static void cmd_new_blob()
                free(d);
 }
 
-static void unload_one_branch()
+static void unload_one_branch(void)
 {
        while (cur_active_branches
                && cur_active_branches >= max_active_branches) {
-               unsigned long min_commit = ULONG_MAX;
+               uintmax_t min_commit = ULONG_MAX;
                struct branch *e, *l = NULL, *p = NULL;
 
                for (e = active_branches; e; e = e->active_next_branch) {
@@ -1198,6 +1562,7 @@ static void unload_one_branch()
                        e = active_branches;
                        active_branches = e->active_next_branch;
                }
+               e->active = 0;
                e->active_next_branch = NULL;
                if (e->branch_tree.tree) {
                        release_tree_content_recursive(e->branch_tree.tree);
@@ -1210,10 +1575,13 @@ static void unload_one_branch()
 static void load_branch(struct branch *b)
 {
        load_tree(&b->branch_tree);
-       b->active_next_branch = active_branches;
-       active_branches = b;
-       cur_active_branches++;
-       branch_load_count++;
+       if (!b->active) {
+               b->active = 1;
+               b->active_next_branch = active_branches;
+               active_branches = b;
+               cur_active_branches++;
+               branch_load_count++;
+       }
 }
 
 static void file_change_m(struct branch *b)
@@ -1221,10 +1589,9 @@ static void file_change_m(struct branch *b)
        const char *p = command_buf.buf + 2;
        char *p_uq;
        const char *endp;
-       struct object_entry *oe;
+       struct object_entry *oe = oe;
        unsigned char sha1[20];
-       unsigned int mode;
-       char type[20];
+       uint16_t mode, inline_data = 0;
 
        p = get_mode(p, &mode);
        if (!p)
@@ -1243,8 +1610,12 @@ static void file_change_m(struct branch *b)
 
        if (*p == ':') {
                char *x;
-               oe = find_mark(strtoul(p + 1, &x, 10));
+               oe = find_mark(strtoumax(p + 1, &x, 10));
+               hashcpy(sha1, oe->sha1);
                p = x;
+       } else if (!prefixcmp(p, "inline")) {
+               inline_data = 1;
+               p += 6;
        } else {
                if (get_sha1_hex(p, sha1))
                        die("Invalid SHA1: %s", command_buf.buf);
@@ -1261,22 +1632,30 @@ static void file_change_m(struct branch *b)
                p = p_uq;
        }
 
-       if (oe) {
+       if (inline_data) {
+               size_t l;
+               void *d;
+               if (!p_uq)
+                       p = p_uq = xstrdup(p);
+               read_next_command();
+               d = cmd_data(&l);
+               if (store_object(OBJ_BLOB, d, l, &last_blob, sha1, 0))
+                       free(d);
+       } else if (oe) {
                if (oe->type != OBJ_BLOB)
                        die("Not a blob (actually a %s): %s",
-                               command_buf.buf, type_names[oe->type]);
+                               command_buf.buf, typename(oe->type));
        } else {
-               if (sha1_object_info(sha1, type, NULL))
+               enum object_type type = sha1_object_info(sha1, NULL);
+               if (type < 0)
                        die("Blob not found: %s", command_buf.buf);
-               if (strcmp(blob_type, type))
+               if (type != OBJ_BLOB)
                        die("Not a blob (actually a %s): %s",
-                               command_buf.buf, type);
+                           typename(type), command_buf.buf);
        }
 
        tree_content_set(&b->branch_tree, p, sha1, S_IFREG | mode);
-
-       if (p_uq)
-               free(p_uq);
+       free(p_uq);
 }
 
 static void file_change_d(struct branch *b)
@@ -1292,49 +1671,155 @@ static void file_change_d(struct branch *b)
                p = p_uq;
        }
        tree_content_remove(&b->branch_tree, p);
-       if (p_uq)
-               free(p_uq);
+       free(p_uq);
+}
+
+static void file_change_deleteall(struct branch *b)
+{
+       release_tree_content_recursive(b->branch_tree.tree);
+       hashclr(b->branch_tree.versions[0].sha1);
+       hashclr(b->branch_tree.versions[1].sha1);
+       load_tree(&b->branch_tree);
 }
 
-static void cmd_new_commit()
+static void cmd_from(struct branch *b)
+{
+       const char *from;
+       struct branch *s;
+
+       if (prefixcmp(command_buf.buf, "from "))
+               return;
+
+       if (b->branch_tree.tree) {
+               release_tree_content_recursive(b->branch_tree.tree);
+               b->branch_tree.tree = NULL;
+       }
+
+       from = strchr(command_buf.buf, ' ') + 1;
+       s = lookup_branch(from);
+       if (b == s)
+               die("Can't create a branch from itself: %s", b->name);
+       else if (s) {
+               unsigned char *t = s->branch_tree.versions[1].sha1;
+               hashcpy(b->sha1, s->sha1);
+               hashcpy(b->branch_tree.versions[0].sha1, t);
+               hashcpy(b->branch_tree.versions[1].sha1, t);
+       } else if (*from == ':') {
+               uintmax_t idnum = strtoumax(from + 1, NULL, 10);
+               struct object_entry *oe = find_mark(idnum);
+               unsigned long size;
+               char *buf;
+               if (oe->type != OBJ_COMMIT)
+                       die("Mark :%" PRIuMAX " not a commit", idnum);
+               hashcpy(b->sha1, oe->sha1);
+               buf = gfi_unpack_entry(oe, &size);
+               if (!buf || size < 46)
+                       die("Not a valid commit: %s", from);
+               if (memcmp("tree ", buf, 5)
+                       || get_sha1_hex(buf + 5, b->branch_tree.versions[1].sha1))
+                       die("The commit %s is corrupt", sha1_to_hex(b->sha1));
+               free(buf);
+               hashcpy(b->branch_tree.versions[0].sha1,
+                       b->branch_tree.versions[1].sha1);
+       } else if (!get_sha1(from, b->sha1)) {
+               if (is_null_sha1(b->sha1)) {
+                       hashclr(b->branch_tree.versions[0].sha1);
+                       hashclr(b->branch_tree.versions[1].sha1);
+               } else {
+                       unsigned long size;
+                       char *buf;
+
+                       buf = read_object_with_reference(b->sha1,
+                               commit_type, &size, b->sha1);
+                       if (!buf || size < 46)
+                               die("Not a valid commit: %s", from);
+                       if (memcmp("tree ", buf, 5)
+                               || get_sha1_hex(buf + 5, b->branch_tree.versions[1].sha1))
+                               die("The commit %s is corrupt", sha1_to_hex(b->sha1));
+                       free(buf);
+                       hashcpy(b->branch_tree.versions[0].sha1,
+                               b->branch_tree.versions[1].sha1);
+               }
+       } else
+               die("Invalid ref name or SHA1 expression: %s", from);
+
+       read_next_command();
+}
+
+static struct hash_list *cmd_merge(unsigned int *count)
+{
+       struct hash_list *list = NULL, *n, *e = e;
+       const char *from;
+       struct branch *s;
+
+       *count = 0;
+       while (!prefixcmp(command_buf.buf, "merge ")) {
+               from = strchr(command_buf.buf, ' ') + 1;
+               n = xmalloc(sizeof(*n));
+               s = lookup_branch(from);
+               if (s)
+                       hashcpy(n->sha1, s->sha1);
+               else if (*from == ':') {
+                       uintmax_t idnum = strtoumax(from + 1, NULL, 10);
+                       struct object_entry *oe = find_mark(idnum);
+                       if (oe->type != OBJ_COMMIT)
+                               die("Mark :%" PRIuMAX " not a commit", idnum);
+                       hashcpy(n->sha1, oe->sha1);
+               } else if (!get_sha1(from, n->sha1)) {
+                       unsigned long size;
+                       char *buf = read_object_with_reference(n->sha1,
+                               commit_type, &size, n->sha1);
+                       if (!buf || size < 46)
+                               die("Not a valid commit: %s", from);
+                       free(buf);
+               } else
+                       die("Invalid ref name or SHA1 expression: %s", from);
+
+               n->next = NULL;
+               if (list)
+                       e->next = n;
+               else
+                       list = n;
+               e = n;
+               (*count)++;
+               read_next_command();
+       }
+       return list;
+}
+
+static void cmd_new_commit(void)
 {
        struct branch *b;
        void *msg;
        size_t msglen;
-       char *str_uq;
-       const char *endp;
        char *sp;
        char *author = NULL;
        char *committer = NULL;
-       char *body;
+       struct hash_list *merge_list = NULL;
+       unsigned int merge_count;
 
        /* Obtain the branch name from the rest of our command */
        sp = strchr(command_buf.buf, ' ') + 1;
-       str_uq = unquote_c_style(sp, &endp);
-       if (str_uq) {
-               if (*endp)
-                       die("Garbage after ref in: %s", command_buf.buf);
-               sp = str_uq;
-       }
        b = lookup_branch(sp);
        if (!b)
-               die("Branch not declared: %s", sp);
-       if (str_uq)
-               free(str_uq);
+               b = new_branch(sp);
 
        read_next_command();
        cmd_mark();
-       if (!strncmp("author ", command_buf.buf, 7)) {
-               author = strdup(command_buf.buf);
+       if (!prefixcmp(command_buf.buf, "author ")) {
+               author = parse_ident(command_buf.buf + 7);
                read_next_command();
        }
-       if (!strncmp("committer ", command_buf.buf, 10)) {
-               committer = strdup(command_buf.buf);
+       if (!prefixcmp(command_buf.buf, "committer ")) {
+               committer = parse_ident(command_buf.buf + 10);
                read_next_command();
        }
        if (!committer)
                die("Expected committer but didn't get one");
        msg = cmd_data(&msglen);
+       read_next_command();
+       cmd_from(b);
+       merge_list = cmd_merge(&merge_count);
 
        /* ensure the branch is active/loaded */
        if (!b->branch_tree.tree || !max_active_branches) {
@@ -1344,151 +1829,69 @@ static void cmd_new_commit()
 
        /* file_change* */
        for (;;) {
-               read_next_command();
                if (1 == command_buf.len)
                        break;
-               else if (!strncmp("M ", command_buf.buf, 2))
+               else if (!prefixcmp(command_buf.buf, "M "))
                        file_change_m(b);
-               else if (!strncmp("D ", command_buf.buf, 2))
+               else if (!prefixcmp(command_buf.buf, "D "))
                        file_change_d(b);
+               else if (!strcmp("deleteall", command_buf.buf))
+                       file_change_deleteall(b);
                else
                        die("Unsupported file_change: %s", command_buf.buf);
+               read_next_command();
        }
 
        /* build the tree and the commit */
        store_tree(&b->branch_tree);
-       body = xmalloc(97 + msglen
+       hashcpy(b->branch_tree.versions[0].sha1,
+               b->branch_tree.versions[1].sha1);
+       size_dbuf(&new_data, 114 + msglen
+               + merge_count * 49
                + (author
                        ? strlen(author) + strlen(committer)
                        : 2 * strlen(committer)));
-       sp = body;
-       sp += sprintf(sp, "tree %s\n", sha1_to_hex(b->branch_tree.sha1));
-       if (memcmp(b->sha1, null_sha1, 20))
+       sp = new_data.buffer;
+       sp += sprintf(sp, "tree %s\n",
+               sha1_to_hex(b->branch_tree.versions[1].sha1));
+       if (!is_null_sha1(b->sha1))
                sp += sprintf(sp, "parent %s\n", sha1_to_hex(b->sha1));
-       if (author)
-               sp += sprintf(sp, "%s\n", author);
-       else
-               sp += sprintf(sp, "author %s\n", committer + 10);
-       sp += sprintf(sp, "%s\n\n", committer);
+       while (merge_list) {
+               struct hash_list *next = merge_list->next;
+               sp += sprintf(sp, "parent %s\n", sha1_to_hex(merge_list->sha1));
+               free(merge_list);
+               merge_list = next;
+       }
+       sp += sprintf(sp, "author %s\n", author ? author : committer);
+       sp += sprintf(sp, "committer %s\n", committer);
+       *sp++ = '\n';
        memcpy(sp, msg, msglen);
        sp += msglen;
-       if (author)
-               free(author);
+       free(author);
        free(committer);
        free(msg);
 
-       store_object(OBJ_COMMIT, body, sp - body, NULL, b->sha1, next_mark);
-       free(body);
+       if (!store_object(OBJ_COMMIT,
+               new_data.buffer, sp - (char*)new_data.buffer,
+               NULL, b->sha1, next_mark))
+               b->pack_id = pack_id;
        b->last_commit = object_count_by_type[OBJ_COMMIT];
 }
 
-static void cmd_new_branch()
+static void cmd_new_tag(void)
 {
-       struct branch *b;
-       char *str_uq;
-       const char *endp;
-       char *sp;
-
-       /* Obtain the new branch name from the rest of our command */
-       sp = strchr(command_buf.buf, ' ') + 1;
-       str_uq = unquote_c_style(sp, &endp);
-       if (str_uq) {
-               if (*endp)
-                       die("Garbage after ref in: %s", command_buf.buf);
-               sp = str_uq;
-       }
-       b = new_branch(sp);
-       if (str_uq)
-               free(str_uq);
-       read_next_command();
-
-       /* from ... */
-       if (!strncmp("from ", command_buf.buf, 5)) {
-               const char *from;
-               struct branch *s;
-
-               from = strchr(command_buf.buf, ' ') + 1;
-               str_uq = unquote_c_style(from, &endp);
-               if (str_uq) {
-                       if (*endp)
-                               die("Garbage after string in: %s", command_buf.buf);
-                       from = str_uq;
-               }
-
-               s = lookup_branch(from);
-               if (b == s)
-                       die("Can't create a branch from itself: %s", b->name);
-               else if (s) {
-                       memcpy(b->sha1, s->sha1, 20);
-                       memcpy(b->branch_tree.sha1, s->branch_tree.sha1, 20);
-               } else if (*from == ':') {
-                       unsigned long idnum = strtoul(from + 1, NULL, 10);
-                       struct object_entry *oe = find_mark(idnum);
-                       unsigned long size;
-                       char *buf;
-                       if (oe->type != OBJ_COMMIT)
-                               die("Mark :%lu not a commit", idnum);
-                       memcpy(b->sha1, oe->sha1, 20);
-                       buf = unpack_entry(oe->offset, &size);
-                       if (!buf || size < 46)
-                               die("Not a valid commit: %s", from);
-                       if (memcmp("tree ", buf, 5)
-                               || get_sha1_hex(buf + 5, b->branch_tree.sha1))
-                               die("The commit %s is corrupt", sha1_to_hex(b->sha1));
-                       free(buf);
-               } else if (!get_sha1(from, b->sha1)) {
-                       if (!memcmp(b->sha1, null_sha1, 20))
-                               memcpy(b->branch_tree.sha1, null_sha1, 20);
-                       else {
-                               unsigned long size;
-                               char *buf;
-
-                               buf = read_object_with_reference(b->sha1,
-                                       type_names[OBJ_COMMIT], &size, b->sha1);
-                               if (!buf || size < 46)
-                                       die("Not a valid commit: %s", from);
-                               if (memcmp("tree ", buf, 5)
-                                       || get_sha1_hex(buf + 5, b->branch_tree.sha1))
-                                       die("The commit %s is corrupt", sha1_to_hex(b->sha1));
-                               free(buf);
-                       }
-               } else
-                       die("Invalid ref name or SHA1 expression: %s", from);
-
-               if (str_uq)
-                       free(str_uq);
-               read_next_command();
-       } else {
-               memcpy(b->sha1, null_sha1, 20);
-               memcpy(b->branch_tree.sha1, null_sha1, 20);
-       }
-
-       if (command_buf.eof || command_buf.len > 1)
-               die("An lf did not terminate the branch command as expected.");
-}
-
-static void cmd_new_tag()
-{
-       char *str_uq;
-       const char *endp;
        char *sp;
        const char *from;
        char *tagger;
        struct branch *s;
        void *msg;
        size_t msglen;
-       char *body;
        struct tag *t;
+       uintmax_t from_mark = 0;
        unsigned char sha1[20];
 
        /* Obtain the new tag name from the rest of our command */
        sp = strchr(command_buf.buf, ' ') + 1;
-       str_uq = unquote_c_style(sp, &endp);
-       if (str_uq) {
-               if (*endp)
-                       die("Garbage after tag name in: %s", command_buf.buf);
-               sp = str_uq;
-       }
        t = pool_alloc(sizeof(struct tag));
        t->next_tag = NULL;
        t->name = pool_strdup(sp);
@@ -1497,168 +1900,246 @@ static void cmd_new_tag()
        else
                first_tag = t;
        last_tag = t;
-       if (str_uq)
-               free(str_uq);
        read_next_command();
 
        /* from ... */
-       if (strncmp("from ", command_buf.buf, 5))
+       if (prefixcmp(command_buf.buf, "from "))
                die("Expected from command, got %s", command_buf.buf);
-
        from = strchr(command_buf.buf, ' ') + 1;
-       str_uq = unquote_c_style(from, &endp);
-       if (str_uq) {
-               if (*endp)
-                       die("Garbage after string in: %s", command_buf.buf);
-               from = str_uq;
-       }
-
        s = lookup_branch(from);
        if (s) {
-               memcpy(sha1, s->sha1, 20);
+               hashcpy(sha1, s->sha1);
        } else if (*from == ':') {
-               unsigned long idnum = strtoul(from + 1, NULL, 10);
-               struct object_entry *oe = find_mark(idnum);
+               struct object_entry *oe;
+               from_mark = strtoumax(from + 1, NULL, 10);
+               oe = find_mark(from_mark);
                if (oe->type != OBJ_COMMIT)
-                       die("Mark :%lu not a commit", idnum);
-               memcpy(sha1, oe->sha1, 20);
+                       die("Mark :%" PRIuMAX " not a commit", from_mark);
+               hashcpy(sha1, oe->sha1);
        } else if (!get_sha1(from, sha1)) {
                unsigned long size;
                char *buf;
 
                buf = read_object_with_reference(sha1,
-                       type_names[OBJ_COMMIT], &size, sha1);
+                       commit_type, &size, sha1);
                if (!buf || size < 46)
                        die("Not a valid commit: %s", from);
                free(buf);
        } else
                die("Invalid ref name or SHA1 expression: %s", from);
-
-       if (str_uq)
-               free(str_uq);
        read_next_command();
 
        /* tagger ... */
-       if (strncmp("tagger ", command_buf.buf, 7))
+       if (prefixcmp(command_buf.buf, "tagger "))
                die("Expected tagger command, got %s", command_buf.buf);
-       tagger = strdup(command_buf.buf);
+       tagger = parse_ident(command_buf.buf + 7);
 
        /* tag payload/message */
        read_next_command();
        msg = cmd_data(&msglen);
 
        /* build the tag object */
-       body = xmalloc(67 + strlen(t->name) + strlen(tagger) + msglen);
-       sp = body;
+       size_dbuf(&new_data, 67+strlen(t->name)+strlen(tagger)+msglen);
+       sp = new_data.buffer;
        sp += sprintf(sp, "object %s\n", sha1_to_hex(sha1));
-       sp += sprintf(sp, "type %s\n", type_names[OBJ_COMMIT]);
+       sp += sprintf(sp, "type %s\n", commit_type);
        sp += sprintf(sp, "tag %s\n", t->name);
-       sp += sprintf(sp, "%s\n\n", tagger);
+       sp += sprintf(sp, "tagger %s\n", tagger);
+       *sp++ = '\n';
        memcpy(sp, msg, msglen);
        sp += msglen;
        free(tagger);
        free(msg);
 
-       store_object(OBJ_TAG, body, sp - body, NULL, t->sha1, 0);
-       free(body);
+       if (store_object(OBJ_TAG, new_data.buffer,
+               sp - (char*)new_data.buffer,
+               NULL, t->sha1, 0))
+               t->pack_id = MAX_PACK_ID;
+       else
+               t->pack_id = pack_id;
+}
+
+static void cmd_reset_branch(void)
+{
+       struct branch *b;
+       char *sp;
+
+       /* Obtain the branch name from the rest of our command */
+       sp = strchr(command_buf.buf, ' ') + 1;
+       b = lookup_branch(sp);
+       if (b) {
+               hashclr(b->sha1);
+               hashclr(b->branch_tree.versions[0].sha1);
+               hashclr(b->branch_tree.versions[1].sha1);
+               if (b->branch_tree.tree) {
+                       release_tree_content_recursive(b->branch_tree.tree);
+                       b->branch_tree.tree = NULL;
+               }
+       }
+       else
+               b = new_branch(sp);
+       read_next_command();
+       cmd_from(b);
+}
+
+static void cmd_checkpoint(void)
+{
+       if (object_count) {
+               cycle_packfile();
+               dump_branches();
+               dump_tags();
+               dump_marks();
+       }
+       read_next_command();
+}
+
+static void import_marks(const char *input_file)
+{
+       char line[512];
+       FILE *f = fopen(input_file, "r");
+       if (!f)
+               die("cannot read %s: %s", input_file, strerror(errno));
+       while (fgets(line, sizeof(line), f)) {
+               uintmax_t mark;
+               char *end;
+               unsigned char sha1[20];
+               struct object_entry *e;
+
+               end = strchr(line, '\n');
+               if (line[0] != ':' || !end)
+                       die("corrupt mark line: %s", line);
+               *end = 0;
+               mark = strtoumax(line + 1, &end, 10);
+               if (!mark || end == line + 1
+                       || *end != ' ' || get_sha1(end + 1, sha1))
+                       die("corrupt mark line: %s", line);
+               e = find_object(sha1);
+               if (!e) {
+                       enum object_type type = sha1_object_info(sha1, NULL);
+                       if (type < 0)
+                               die("object not found: %s", sha1_to_hex(sha1));
+                       e = insert_object(sha1);
+                       e->type = type;
+                       e->pack_id = MAX_PACK_ID;
+               }
+               insert_mark(mark, e);
+       }
+       fclose(f);
 }
 
 static const char fast_import_usage[] =
-"git-fast-import [--objects=n] [--depth=n] [--active-branches=n] temp.pack";
+"git-fast-import [--date-format=f] [--max-pack-size=n] [--depth=n] [--active-branches=n] [--export-marks=marks.file]";
 
 int main(int argc, const char **argv)
 {
-       const char *base_name;
-       int i;
-       unsigned long est_obj_cnt = 1000;
-       char *pack_name;
-       char *idx_name;
-       struct stat sb;
+       int i, show_stats = 1;
 
-       setup_ident();
        git_config(git_default_config);
+       alloc_objects(object_entry_alloc);
+       strbuf_init(&command_buf);
+       atom_table = xcalloc(atom_table_sz, sizeof(struct atom_str*));
+       branch_table = xcalloc(branch_table_sz, sizeof(struct branch*));
+       avail_tree_table = xcalloc(avail_tree_table_sz, sizeof(struct avail_tree_content*));
+       marks = pool_calloc(1, sizeof(struct mark_set));
 
        for (i = 1; i < argc; i++) {
                const char *a = argv[i];
 
                if (*a != '-' || !strcmp(a, "--"))
                        break;
-               else if (!strncmp(a, "--objects=", 10))
-                       est_obj_cnt = strtoul(a + 10, NULL, 0);
-               else if (!strncmp(a, "--depth=", 8))
+               else if (!prefixcmp(a, "--date-format=")) {
+                       const char *fmt = a + 14;
+                       if (!strcmp(fmt, "raw"))
+                               whenspec = WHENSPEC_RAW;
+                       else if (!strcmp(fmt, "rfc2822"))
+                               whenspec = WHENSPEC_RFC2822;
+                       else if (!strcmp(fmt, "now"))
+                               whenspec = WHENSPEC_NOW;
+                       else
+                               die("unknown --date-format argument %s", fmt);
+               }
+               else if (!prefixcmp(a, "--max-pack-size="))
+                       max_packsize = strtoumax(a + 16, NULL, 0) * 1024 * 1024;
+               else if (!prefixcmp(a, "--depth="))
                        max_depth = strtoul(a + 8, NULL, 0);
-               else if (!strncmp(a, "--active-branches=", 18))
+               else if (!prefixcmp(a, "--active-branches="))
                        max_active_branches = strtoul(a + 18, NULL, 0);
+               else if (!prefixcmp(a, "--import-marks="))
+                       import_marks(a + 15);
+               else if (!prefixcmp(a, "--export-marks="))
+                       mark_file = a + 15;
+               else if (!prefixcmp(a, "--export-pack-edges=")) {
+                       if (pack_edges)
+                               fclose(pack_edges);
+                       pack_edges = fopen(a + 20, "a");
+                       if (!pack_edges)
+                               die("Cannot open %s: %s", a + 20, strerror(errno));
+               } else if (!strcmp(a, "--force"))
+                       force_update = 1;
+               else if (!strcmp(a, "--quiet"))
+                       show_stats = 0;
+               else if (!strcmp(a, "--stats"))
+                       show_stats = 1;
                else
                        die("unknown option %s", a);
        }
-       if ((i+1) != argc)
+       if (i != argc)
                usage(fast_import_usage);
-       base_name = argv[i];
-
-       pack_name = xmalloc(strlen(base_name) + 6);
-       sprintf(pack_name, "%s.pack", base_name);
-       idx_name = xmalloc(strlen(base_name) + 5);
-       sprintf(idx_name, "%s.idx", base_name);
-
-       pack_fd = open(pack_name, O_RDWR|O_CREAT|O_EXCL, 0666);
-       if (pack_fd < 0)
-               die("Can't create %s: %s", pack_name, strerror(errno));
-
-       init_pack_header();
-       alloc_objects(est_obj_cnt);
-       strbuf_init(&command_buf);
-
-       atom_table = xcalloc(atom_table_sz, sizeof(struct atom_str*));
-       branch_table = xcalloc(branch_table_sz, sizeof(struct branch*));
-       avail_tree_table = xcalloc(avail_tree_table_sz, sizeof(struct avail_tree_content*));
-       marks = pool_calloc(1, sizeof(struct mark_set));
 
+       start_packfile();
        for (;;) {
                read_next_command();
                if (command_buf.eof)
                        break;
                else if (!strcmp("blob", command_buf.buf))
                        cmd_new_blob();
-               else if (!strncmp("branch ", command_buf.buf, 7))
-                       cmd_new_branch();
-               else if (!strncmp("commit ", command_buf.buf, 7))
+               else if (!prefixcmp(command_buf.buf, "commit "))
                        cmd_new_commit();
-               else if (!strncmp("tag ", command_buf.buf, 4))
+               else if (!prefixcmp(command_buf.buf, "tag "))
                        cmd_new_tag();
+               else if (!prefixcmp(command_buf.buf, "reset "))
+                       cmd_reset_branch();
+               else if (!strcmp("checkpoint", command_buf.buf))
+                       cmd_checkpoint();
                else
                        die("Unsupported command: %s", command_buf.buf);
        }
+       end_packfile();
 
-       fixup_header_footer();
-       close(pack_fd);
-       write_index(idx_name);
        dump_branches();
        dump_tags();
+       unkeep_all_packs();
+       dump_marks();
+
+       if (pack_edges)
+               fclose(pack_edges);
+
+       if (show_stats) {
+               uintmax_t total_count = 0, duplicate_count = 0;
+               for (i = 0; i < ARRAY_SIZE(object_count_by_type); i++)
+                       total_count += object_count_by_type[i];
+               for (i = 0; i < ARRAY_SIZE(duplicate_count_by_type); i++)
+                       duplicate_count += duplicate_count_by_type[i];
+
+               fprintf(stderr, "%s statistics:\n", argv[0]);
+               fprintf(stderr, "---------------------------------------------------------------------\n");
+               fprintf(stderr, "Alloc'd objects: %10" PRIuMAX "\n", alloc_count);
+               fprintf(stderr, "Total objects:   %10" PRIuMAX " (%10" PRIuMAX " duplicates                  )\n", total_count, duplicate_count);
+               fprintf(stderr, "      blobs  :   %10" PRIuMAX " (%10" PRIuMAX " duplicates %10" PRIuMAX " deltas)\n", object_count_by_type[OBJ_BLOB], duplicate_count_by_type[OBJ_BLOB], delta_count_by_type[OBJ_BLOB]);
+               fprintf(stderr, "      trees  :   %10" PRIuMAX " (%10" PRIuMAX " duplicates %10" PRIuMAX " deltas)\n", object_count_by_type[OBJ_TREE], duplicate_count_by_type[OBJ_TREE], delta_count_by_type[OBJ_TREE]);
+               fprintf(stderr, "      commits:   %10" PRIuMAX " (%10" PRIuMAX " duplicates %10" PRIuMAX " deltas)\n", object_count_by_type[OBJ_COMMIT], duplicate_count_by_type[OBJ_COMMIT], delta_count_by_type[OBJ_COMMIT]);
+               fprintf(stderr, "      tags   :   %10" PRIuMAX " (%10" PRIuMAX " duplicates %10" PRIuMAX " deltas)\n", object_count_by_type[OBJ_TAG], duplicate_count_by_type[OBJ_TAG], delta_count_by_type[OBJ_TAG]);
+               fprintf(stderr, "Total branches:  %10lu (%10lu loads     )\n", branch_count, branch_load_count);
+               fprintf(stderr, "      marks:     %10" PRIuMAX " (%10" PRIuMAX " unique    )\n", (((uintmax_t)1) << marks->shift) * 1024, marks_set_count);
+               fprintf(stderr, "      atoms:     %10u\n", atom_cnt);
+               fprintf(stderr, "Memory total:    %10" PRIuMAX " KiB\n", (total_allocd + alloc_count*sizeof(struct object_entry))/1024);
+               fprintf(stderr, "       pools:    %10lu KiB\n", (unsigned long)(total_allocd/1024));
+               fprintf(stderr, "     objects:    %10" PRIuMAX " KiB\n", (alloc_count*sizeof(struct object_entry))/1024);
+               fprintf(stderr, "---------------------------------------------------------------------\n");
+               pack_report();
+               fprintf(stderr, "---------------------------------------------------------------------\n");
+               fprintf(stderr, "\n");
+       }
 
-       fprintf(stderr, "%s statistics:\n", argv[0]);
-       fprintf(stderr, "---------------------------------------------------\n");
-       fprintf(stderr, "Alloc'd objects: %10lu (%10lu overflow  )\n", alloc_count, alloc_count - est_obj_cnt);
-       fprintf(stderr, "Total objects:   %10lu (%10lu duplicates)\n", object_count, duplicate_count);
-       fprintf(stderr, "      blobs  :   %10lu (%10lu duplicates)\n", object_count_by_type[OBJ_BLOB], duplicate_count_by_type[OBJ_BLOB]);
-       fprintf(stderr, "      trees  :   %10lu (%10lu duplicates)\n", object_count_by_type[OBJ_TREE], duplicate_count_by_type[OBJ_TREE]);
-       fprintf(stderr, "      commits:   %10lu (%10lu duplicates)\n", object_count_by_type[OBJ_COMMIT], duplicate_count_by_type[OBJ_COMMIT]);
-       fprintf(stderr, "      tags   :   %10lu (%10lu duplicates)\n", object_count_by_type[OBJ_TAG], duplicate_count_by_type[OBJ_TAG]);
-       fprintf(stderr, "Total branches:  %10lu (%10lu loads     )\n", branch_count, branch_load_count);
-       fprintf(stderr, "      marks:     %10u (%10lu unique    )\n", (1 << marks->shift) * 1024, marks_set_count);
-       fprintf(stderr, "      atoms:     %10u\n", atom_cnt);
-       fprintf(stderr, "Memory total:    %10lu KiB\n", (total_allocd + alloc_count*sizeof(struct object_entry))/1024);
-       fprintf(stderr, "       pools:    %10lu KiB\n", total_allocd/1024);
-       fprintf(stderr, "     objects:    %10lu KiB\n", (alloc_count*sizeof(struct object_entry))/1024);
-       fprintf(stderr, "Pack remaps:     %10lu\n", remap_count);
-       fprintf(stderr, "---------------------------------------------------\n");
-
-       stat(pack_name, &sb);
-       fprintf(stderr, "Pack size:       %10lu KiB\n", (unsigned long)(sb.st_size/1024));
-       stat(idx_name, &sb);
-       fprintf(stderr, "Index size:      %10lu KiB\n", (unsigned long)(sb.st_size/1024));
-
-       fprintf(stderr, "\n");
-
-       return 0;
+       return failure ? 1 : 0;
 }