rix->revindex = xmalloc(sizeof(unsigned long) * (num_ent + 1));
for (i = 0; i < num_ent; i++) {
- long hl = *((long *)(index + 24 * i));
+ unsigned int hl = *((unsigned int *)(index + 24 * i));
rix->revindex[i] = ntohl(hl);
}
/* This knows the pack format -- the 20-byte trailer
if (object_ix_hashsz < 1024)
object_ix_hashsz = 1024;
object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
- object_ix = memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
+ memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
int ix = locate_object_entry_hash(oe->sha1);
if (0 <= ix)
}
}
-struct name_path {
- struct name_path *up;
- const char *elem;
- int len;
-};
-
-#define DIRBITS 12
-
-static unsigned name_hash(struct name_path *path, const char *name)
+static unsigned name_hash(const char *name)
{
- struct name_path *p = path;
- const char *n = name + strlen(name);
- unsigned hash = 0, name_hash = 0, name_done = 0;
-
- if (n != name && n[-1] == '\n')
- n--;
- while (name <= --n) {
- unsigned char c = *n;
- if (c == '/' && !name_done) {
- name_hash = hash;
- name_done = 1;
- hash = 0;
- }
- hash = hash * 11 + c;
- }
- if (!name_done) {
- name_hash = hash;
- hash = 0;
- }
- for (p = path; p; p = p->up) {
- hash = hash * 11 + '/';
- n = p->elem + p->len;
- while (p->elem <= --n) {
- unsigned char c = *n;
- hash = hash * 11 + c;
- }
- }
+ unsigned char c;
+ unsigned hash = 0;
+
/*
- * Make sure "Makefile" and "t/Makefile" are hashed separately
- * but close enough.
+ * This effectively just creates a sortable number from the
+ * last sixteen non-whitespace characters. Last characters
+ * count "most", so things that end in ".c" sort together.
*/
- hash = (name_hash<<DIRBITS) | (hash & ((1U<<DIRBITS )-1));
-
- if (0) { /* debug */
- n = name + strlen(name);
- if (n != name && n[-1] == '\n')
- n--;
- while (name <= --n)
- fputc(*n, stderr);
- for (p = path; p; p = p->up) {
- fputc('/', stderr);
- n = p->elem + p->len;
- while (p->elem <= --n)
- fputc(*n, stderr);
- }
- fprintf(stderr, "\t%08x\n", hash);
+ while ((c = *name++) != 0) {
+ if (isspace(c))
+ continue;
+ hash = (hash >> 2) + (c << 24);
}
return hash;
}
return status;
}
-static void add_pbase_tree(struct tree_desc *tree, struct name_path *up)
+struct pbase_tree_cache {
+ unsigned char sha1[20];
+ int ref;
+ int temporary;
+ void *tree_data;
+ unsigned long tree_size;
+};
+
+static struct pbase_tree_cache *(pbase_tree_cache[256]);
+static int pbase_tree_cache_ix(const unsigned char *sha1)
{
- while (tree->size) {
- const unsigned char *sha1;
- const char *name;
- unsigned mode, hash;
+ return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
+}
+static int pbase_tree_cache_ix_incr(int ix)
+{
+ return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
+}
+
+static struct pbase_tree {
+ struct pbase_tree *next;
+ /* This is a phony "cache" entry; we are not
+ * going to evict it nor find it through _get()
+ * mechanism -- this is for the toplevel node that
+ * would almost always change with any commit.
+ */
+ struct pbase_tree_cache pcache;
+} *pbase_tree;
+
+static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
+{
+ struct pbase_tree_cache *ent, *nent;
+ void *data;
+ unsigned long size;
+ char type[20];
+ int neigh;
+ int my_ix = pbase_tree_cache_ix(sha1);
+ int available_ix = -1;
+
+ /* pbase-tree-cache acts as a limited hashtable.
+ * your object will be found at your index or within a few
+ * slots after that slot if it is cached.
+ */
+ for (neigh = 0; neigh < 8; neigh++) {
+ ent = pbase_tree_cache[my_ix];
+ if (ent && !memcmp(ent->sha1, sha1, 20)) {
+ ent->ref++;
+ return ent;
+ }
+ else if (((available_ix < 0) && (!ent || !ent->ref)) ||
+ ((0 <= available_ix) &&
+ (!ent && pbase_tree_cache[available_ix])))
+ available_ix = my_ix;
+ if (!ent)
+ break;
+ my_ix = pbase_tree_cache_ix_incr(my_ix);
+ }
+
+ /* Did not find one. Either we got a bogus request or
+ * we need to read and perhaps cache.
+ */
+ data = read_sha1_file(sha1, type, &size);
+ if (!data)
+ return NULL;
+ if (strcmp(type, tree_type)) {
+ free(data);
+ return NULL;
+ }
+
+ /* We need to either cache or return a throwaway copy */
+
+ if (available_ix < 0)
+ ent = NULL;
+ else {
+ ent = pbase_tree_cache[available_ix];
+ my_ix = available_ix;
+ }
+
+ if (!ent) {
+ nent = xmalloc(sizeof(*nent));
+ nent->temporary = (available_ix < 0);
+ }
+ else {
+ /* evict and reuse */
+ free(ent->tree_data);
+ nent = ent;
+ }
+ memcpy(nent->sha1, sha1, 20);
+ nent->tree_data = data;
+ nent->tree_size = size;
+ nent->ref = 1;
+ if (!nent->temporary)
+ pbase_tree_cache[my_ix] = nent;
+ return nent;
+}
+
+static void pbase_tree_put(struct pbase_tree_cache *cache)
+{
+ if (!cache->temporary) {
+ cache->ref--;
+ return;
+ }
+ free(cache->tree_data);
+ free(cache);
+}
+
+static int name_cmp_len(const char *name)
+{
+ int i;
+ for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
+ ;
+ return i;
+}
+
+static void add_pbase_object(struct tree_desc *tree,
+ const char *name,
+ int cmplen,
+ const char *fullname)
+{
+ struct name_entry entry;
+
+ while (tree_entry(tree,&entry)) {
unsigned long size;
char type[20];
- sha1 = tree_entry_extract(tree, &name, &mode);
- update_tree_entry(tree);
- if (!has_sha1_file(sha1))
- continue;
- if (sha1_object_info(sha1, type, &size))
+ if (entry.pathlen != cmplen ||
+ memcmp(entry.path, name, cmplen) ||
+ !has_sha1_file(entry.sha1) ||
+ sha1_object_info(entry.sha1, type, &size))
continue;
-
- hash = name_hash(up, name);
- if (!add_object_entry(sha1, hash, 1))
- continue;
-
+ if (name[cmplen] != '/') {
+ unsigned hash = name_hash(fullname);
+ add_object_entry(entry.sha1, hash, 1);
+ return;
+ }
if (!strcmp(type, tree_type)) {
struct tree_desc sub;
- void *elem;
- struct name_path me;
-
- elem = read_sha1_file(sha1, type, &sub.size);
- sub.buf = elem;
- if (sub.buf) {
- me.up = up;
- me.elem = name;
- me.len = strlen(name);
- add_pbase_tree(&sub, &me);
- free(elem);
- }
+ struct pbase_tree_cache *tree;
+ const char *down = name+cmplen+1;
+ int downlen = name_cmp_len(down);
+
+ tree = pbase_tree_get(entry.sha1);
+ if (!tree)
+ return;
+ sub.buf = tree->tree_data;
+ sub.size = tree->tree_size;
+
+ add_pbase_object(&sub, down, downlen, fullname);
+ pbase_tree_put(tree);
+ }
+ }
+}
+
+static unsigned *done_pbase_paths;
+static int done_pbase_paths_num;
+static int done_pbase_paths_alloc;
+static int done_pbase_path_pos(unsigned hash)
+{
+ int lo = 0;
+ int hi = done_pbase_paths_num;
+ while (lo < hi) {
+ int mi = (hi + lo) / 2;
+ if (done_pbase_paths[mi] == hash)
+ return mi;
+ if (done_pbase_paths[mi] < hash)
+ hi = mi;
+ else
+ lo = mi + 1;
+ }
+ return -lo-1;
+}
+
+static int check_pbase_path(unsigned hash)
+{
+ int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
+ if (0 <= pos)
+ return 1;
+ pos = -pos - 1;
+ if (done_pbase_paths_alloc <= done_pbase_paths_num) {
+ done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
+ done_pbase_paths = xrealloc(done_pbase_paths,
+ done_pbase_paths_alloc *
+ sizeof(unsigned));
+ }
+ done_pbase_paths_num++;
+ if (pos < done_pbase_paths_num)
+ memmove(done_pbase_paths + pos + 1,
+ done_pbase_paths + pos,
+ (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
+ done_pbase_paths[pos] = hash;
+ return 0;
+}
+
+static void add_preferred_base_object(char *name, unsigned hash)
+{
+ struct pbase_tree *it;
+ int cmplen = name_cmp_len(name);
+
+ if (check_pbase_path(hash))
+ return;
+
+ for (it = pbase_tree; it; it = it->next) {
+ if (cmplen == 0) {
+ hash = name_hash("");
+ add_object_entry(it->pcache.sha1, hash, 1);
+ }
+ else {
+ struct tree_desc tree;
+ tree.buf = it->pcache.tree_data;
+ tree.size = it->pcache.tree_size;
+ add_pbase_object(&tree, name, cmplen, name);
}
}
}
static void add_preferred_base(unsigned char *sha1)
{
- struct tree_desc tree;
- void *elem;
+ struct pbase_tree *it;
+ void *data;
+ unsigned long size;
+ unsigned char tree_sha1[20];
- elem = read_object_with_reference(sha1, tree_type, &tree.size, NULL);
- tree.buf = elem;
- if (!tree.buf)
+ data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
+ if (!data)
return;
- if (add_object_entry(sha1, name_hash(NULL, ""), 1))
- add_pbase_tree(&tree, NULL);
- free(elem);
+
+ for (it = pbase_tree; it; it = it->next) {
+ if (!memcmp(it->pcache.sha1, tree_sha1, 20)) {
+ free(data);
+ return;
+ }
+ }
+
+ it = xcalloc(1, sizeof(*it));
+ it->next = pbase_tree;
+ pbase_tree = it;
+
+ memcpy(it->pcache.sha1, tree_sha1, 20);
+ it->pcache.tree_data = data;
+ it->pcache.tree_size = size;
}
static void check_object(struct object_entry *entry)
struct unpacked {
struct object_entry *entry;
void *data;
+ struct delta_index *index;
};
/*
* more importantly, the bigger file is likely the more recent
* one.
*/
-static int try_delta(struct unpacked *cur, struct unpacked *old, unsigned max_depth)
+static int try_delta(struct unpacked *trg, struct unpacked *src,
+ struct delta_index *src_index, unsigned max_depth)
{
- struct object_entry *cur_entry = cur->entry;
- struct object_entry *old_entry = old->entry;
- unsigned long size, oldsize, delta_size, sizediff;
- long max_size;
+ struct object_entry *trg_entry = trg->entry;
+ struct object_entry *src_entry = src->entry;
+ unsigned long size, src_size, delta_size, sizediff, max_size;
void *delta_buf;
/* Don't bother doing diffs between different types */
- if (cur_entry->type != old_entry->type)
+ if (trg_entry->type != src_entry->type)
return -1;
/* We do not compute delta to *create* objects we are not
* going to pack.
*/
- if (cur_entry->preferred_base)
+ if (trg_entry->preferred_base)
return -1;
- /* If the current object is at pack edge, take the depth the
+ /*
+ * If the current object is at pack edge, take the depth the
* objects that depend on the current object into account --
* otherwise they would become too deep.
*/
- if (cur_entry->delta_child) {
- if (max_depth <= cur_entry->delta_limit)
+ if (trg_entry->delta_child) {
+ if (max_depth <= trg_entry->delta_limit)
return 0;
- max_depth -= cur_entry->delta_limit;
+ max_depth -= trg_entry->delta_limit;
}
-
- size = cur_entry->size;
- oldsize = old_entry->size;
- sizediff = oldsize > size ? oldsize - size : size - oldsize;
-
- if (size < 50)
- return -1;
- if (old_entry->depth >= max_depth)
+ if (src_entry->depth >= max_depth)
return 0;
- /*
- * NOTE!
- *
- * We always delta from the bigger to the smaller, since that's
- * more space-efficient (deletes don't have to say _what_ they
- * delete).
- */
- max_size = size / 2 - 20;
- if (cur_entry->delta)
- max_size = cur_entry->delta_size-1;
+ /* Now some size filtering heuristics. */
+ size = trg_entry->size;
+ max_size = size/2 - 20;
+ max_size = max_size * (max_depth - src_entry->depth) / max_depth;
+ if (max_size == 0)
+ return 0;
+ if (trg_entry->delta && trg_entry->delta_size <= max_size)
+ max_size = trg_entry->delta_size-1;
+ src_size = src_entry->size;
+ sizediff = src_size < size ? size - src_size : 0;
if (sizediff >= max_size)
- return -1;
- delta_buf = diff_delta(old->data, oldsize,
- cur->data, size, &delta_size, max_size);
+ return 0;
+
+ delta_buf = create_delta(src_index, trg->data, size, &delta_size, max_size);
if (!delta_buf)
return 0;
- cur_entry->delta = old_entry;
- cur_entry->delta_size = delta_size;
- cur_entry->depth = old_entry->depth + 1;
+
+ trg_entry->delta = src_entry;
+ trg_entry->delta_size = delta_size;
+ trg_entry->depth = src_entry->depth + 1;
free(delta_buf);
- return 0;
+ return 1;
}
static void progress_interval(int signum)
*/
continue;
+ if (entry->size < 50)
+ continue;
+ free_delta_index(n->index);
+ n->index = NULL;
free(n->data);
n->entry = entry;
n->data = read_sha1_file(entry->sha1, type, &size);
if (size != entry->size)
- die("object %s inconsistent object length (%lu vs %lu)", sha1_to_hex(entry->sha1), size, entry->size);
+ die("object %s inconsistent object length (%lu vs %lu)",
+ sha1_to_hex(entry->sha1), size, entry->size);
j = window;
while (--j > 0) {
m = array + other_idx;
if (!m->entry)
break;
- if (try_delta(n, m, depth) < 0)
+ if (try_delta(n, m, m->index, depth) < 0)
break;
}
-#if 0
/* if we made n a delta, and if n is already at max
* depth, leaving it in the window is pointless. we
* should evict it first.
- * ... in theory only; somehow this makes things worse.
*/
if (entry->delta && depth <= entry->depth)
continue;
-#endif
+
+ n->index = create_delta_index(n->data, size);
+ if (!n->index)
+ die("out of memory");
+
idx++;
if (idx >= window)
idx = 0;
if (progress)
fputc('\n', stderr);
- for (i = 0; i < window; ++i)
+ for (i = 0; i < window; ++i) {
+ free_delta_index(array[i].index);
free(array[i].data);
+ }
free(array);
}
int main(int argc, char **argv)
{
SHA_CTX ctx;
- char line[PATH_MAX + 20];
+ char line[40 + 1 + PATH_MAX + 2];
int window = 10, depth = 10, pack_to_stdout = 0;
struct object_entry **list;
+ int num_preferred_base = 0;
int i;
setup_git_directory();
+ progress = isatty(2);
for (i = 1; i < argc; i++) {
const char *arg = argv[i];
usage(pack_usage);
continue;
}
+ if (!strcmp("--progress", arg)) {
+ progress = 1;
+ continue;
+ }
if (!strcmp("-q", arg)) {
progress = 0;
continue;
for (;;) {
unsigned char sha1[20];
+ unsigned hash;
if (!fgets(line, sizeof(line), stdin)) {
if (feof(stdin))
if (get_sha1_hex(line+1, sha1))
die("expected edge sha1, got garbage:\n %s",
line+1);
- add_preferred_base(sha1);
+ if (num_preferred_base++ < window)
+ add_preferred_base(sha1);
continue;
}
if (get_sha1_hex(line, sha1))
die("expected sha1, got garbage:\n %s", line);
- add_object_entry(sha1, name_hash(NULL, line+41), 0);
+ hash = name_hash(line+41);
+ add_preferred_base_object(line+41, hash);
+ add_object_entry(sha1, hash, 0);
}
if (progress)
fprintf(stderr, "Done counting %d objects.\n", nr_objects);