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-rw-r--r--builtin/pack-redundant.c672
1 files changed, 672 insertions, 0 deletions
diff --git a/builtin/pack-redundant.c b/builtin/pack-redundant.c
new file mode 100644
index 0000000..ecd49ca
--- /dev/null
+++ b/builtin/pack-redundant.c
@@ -0,0 +1,672 @@
+/*
+*
+* Copyright 2005, Lukas Sandstrom <lukass@etek.chalmers.se>
+*
+* This file is licensed under the GPL v2.
+*
+*/
+
+#include "builtin.h"
+#include "repository.h"
+#include "packfile.h"
+#include "object-store.h"
+
+#define BLKSIZE 512
+
+static const char pack_redundant_usage[] =
+"git pack-redundant [--verbose] [--alt-odb] (--all | <pack-filename>...)";
+
+static int load_all_packs, verbose, alt_odb;
+
+struct llist_item {
+ struct llist_item *next;
+ struct object_id oid;
+};
+static struct llist {
+ struct llist_item *front;
+ struct llist_item *back;
+ size_t size;
+} *all_objects; /* all objects which must be present in local packfiles */
+
+static struct pack_list {
+ struct pack_list *next;
+ struct packed_git *pack;
+ struct llist *unique_objects;
+ struct llist *remaining_objects;
+ size_t all_objects_size;
+} *local_packs = NULL, *altodb_packs = NULL;
+
+static struct llist_item *free_nodes;
+
+static inline void llist_item_put(struct llist_item *item)
+{
+ item->next = free_nodes;
+ free_nodes = item;
+}
+
+static inline struct llist_item *llist_item_get(void)
+{
+ struct llist_item *new_item;
+ if ( free_nodes ) {
+ new_item = free_nodes;
+ free_nodes = free_nodes->next;
+ } else {
+ int i = 1;
+ ALLOC_ARRAY(new_item, BLKSIZE);
+ for (; i < BLKSIZE; i++)
+ llist_item_put(&new_item[i]);
+ }
+ return new_item;
+}
+
+static inline void llist_init(struct llist **list)
+{
+ *list = xmalloc(sizeof(struct llist));
+ (*list)->front = (*list)->back = NULL;
+ (*list)->size = 0;
+}
+
+static struct llist * llist_copy(struct llist *list)
+{
+ struct llist *ret;
+ struct llist_item *new_item, *old_item, *prev;
+
+ llist_init(&ret);
+
+ if ((ret->size = list->size) == 0)
+ return ret;
+
+ new_item = ret->front = llist_item_get();
+ new_item->oid = list->front->oid;
+
+ old_item = list->front->next;
+ while (old_item) {
+ prev = new_item;
+ new_item = llist_item_get();
+ prev->next = new_item;
+ new_item->oid = old_item->oid;
+ old_item = old_item->next;
+ }
+ new_item->next = NULL;
+ ret->back = new_item;
+
+ return ret;
+}
+
+static inline struct llist_item *llist_insert(struct llist *list,
+ struct llist_item *after,
+ const unsigned char *oid)
+{
+ struct llist_item *new_item = llist_item_get();
+ oidread(&new_item->oid, oid);
+ new_item->next = NULL;
+
+ if (after) {
+ new_item->next = after->next;
+ after->next = new_item;
+ if (after == list->back)
+ list->back = new_item;
+ } else {/* insert in front */
+ if (list->size == 0)
+ list->back = new_item;
+ else
+ new_item->next = list->front;
+ list->front = new_item;
+ }
+ list->size++;
+ return new_item;
+}
+
+static inline struct llist_item *llist_insert_back(struct llist *list,
+ const unsigned char *oid)
+{
+ return llist_insert(list, list->back, oid);
+}
+
+static inline struct llist_item *llist_insert_sorted_unique(struct llist *list,
+ const struct object_id *oid, struct llist_item *hint)
+{
+ struct llist_item *prev = NULL, *l;
+
+ l = (hint == NULL) ? list->front : hint;
+ while (l) {
+ int cmp = oidcmp(&l->oid, oid);
+ if (cmp > 0) { /* we insert before this entry */
+ return llist_insert(list, prev, oid->hash);
+ }
+ if (!cmp) { /* already exists */
+ return l;
+ }
+ prev = l;
+ l = l->next;
+ }
+ /* insert at the end */
+ return llist_insert_back(list, oid->hash);
+}
+
+/* returns a pointer to an item in front of sha1 */
+static inline struct llist_item * llist_sorted_remove(struct llist *list, const unsigned char *oid, struct llist_item *hint)
+{
+ struct llist_item *prev, *l;
+
+redo_from_start:
+ l = (hint == NULL) ? list->front : hint;
+ prev = NULL;
+ while (l) {
+ const int cmp = hashcmp(l->oid.hash, oid);
+ if (cmp > 0) /* not in list, since sorted */
+ return prev;
+ if (!cmp) { /* found */
+ if (!prev) {
+ if (hint != NULL && hint != list->front) {
+ /* we don't know the previous element */
+ hint = NULL;
+ goto redo_from_start;
+ }
+ list->front = l->next;
+ } else
+ prev->next = l->next;
+ if (l == list->back)
+ list->back = prev;
+ llist_item_put(l);
+ list->size--;
+ return prev;
+ }
+ prev = l;
+ l = l->next;
+ }
+ return prev;
+}
+
+/* computes A\B */
+static void llist_sorted_difference_inplace(struct llist *A,
+ struct llist *B)
+{
+ struct llist_item *hint, *b;
+
+ hint = NULL;
+ b = B->front;
+
+ while (b) {
+ hint = llist_sorted_remove(A, b->oid.hash, hint);
+ b = b->next;
+ }
+}
+
+static inline struct pack_list * pack_list_insert(struct pack_list **pl,
+ struct pack_list *entry)
+{
+ struct pack_list *p = xmalloc(sizeof(struct pack_list));
+ memcpy(p, entry, sizeof(struct pack_list));
+ p->next = *pl;
+ *pl = p;
+ return p;
+}
+
+static inline size_t pack_list_size(struct pack_list *pl)
+{
+ size_t ret = 0;
+ while (pl) {
+ ret++;
+ pl = pl->next;
+ }
+ return ret;
+}
+
+static struct pack_list * pack_list_difference(const struct pack_list *A,
+ const struct pack_list *B)
+{
+ struct pack_list *ret;
+ const struct pack_list *pl;
+
+ if (!A)
+ return NULL;
+
+ pl = B;
+ while (pl != NULL) {
+ if (A->pack == pl->pack)
+ return pack_list_difference(A->next, B);
+ pl = pl->next;
+ }
+ ret = xmalloc(sizeof(struct pack_list));
+ memcpy(ret, A, sizeof(struct pack_list));
+ ret->next = pack_list_difference(A->next, B);
+ return ret;
+}
+
+static void cmp_two_packs(struct pack_list *p1, struct pack_list *p2)
+{
+ size_t p1_off = 0, p2_off = 0, p1_step, p2_step;
+ const unsigned char *p1_base, *p2_base;
+ struct llist_item *p1_hint = NULL, *p2_hint = NULL;
+ const unsigned int hashsz = the_hash_algo->rawsz;
+
+ if (!p1->unique_objects)
+ p1->unique_objects = llist_copy(p1->remaining_objects);
+ if (!p2->unique_objects)
+ p2->unique_objects = llist_copy(p2->remaining_objects);
+
+ p1_base = p1->pack->index_data;
+ p2_base = p2->pack->index_data;
+ p1_base += 256 * 4 + ((p1->pack->index_version < 2) ? 4 : 8);
+ p2_base += 256 * 4 + ((p2->pack->index_version < 2) ? 4 : 8);
+ p1_step = hashsz + ((p1->pack->index_version < 2) ? 4 : 0);
+ p2_step = hashsz + ((p2->pack->index_version < 2) ? 4 : 0);
+
+ while (p1_off < p1->pack->num_objects * p1_step &&
+ p2_off < p2->pack->num_objects * p2_step)
+ {
+ const int cmp = hashcmp(p1_base + p1_off, p2_base + p2_off);
+ /* cmp ~ p1 - p2 */
+ if (cmp == 0) {
+ p1_hint = llist_sorted_remove(p1->unique_objects,
+ p1_base + p1_off,
+ p1_hint);
+ p2_hint = llist_sorted_remove(p2->unique_objects,
+ p1_base + p1_off,
+ p2_hint);
+ p1_off += p1_step;
+ p2_off += p2_step;
+ continue;
+ }
+ if (cmp < 0) { /* p1 has the object, p2 doesn't */
+ p1_off += p1_step;
+ } else { /* p2 has the object, p1 doesn't */
+ p2_off += p2_step;
+ }
+ }
+}
+
+static size_t sizeof_union(struct packed_git *p1, struct packed_git *p2)
+{
+ size_t ret = 0;
+ size_t p1_off = 0, p2_off = 0, p1_step, p2_step;
+ const unsigned char *p1_base, *p2_base;
+ const unsigned int hashsz = the_hash_algo->rawsz;
+
+ p1_base = p1->index_data;
+ p2_base = p2->index_data;
+ p1_base += 256 * 4 + ((p1->index_version < 2) ? 4 : 8);
+ p2_base += 256 * 4 + ((p2->index_version < 2) ? 4 : 8);
+ p1_step = hashsz + ((p1->index_version < 2) ? 4 : 0);
+ p2_step = hashsz + ((p2->index_version < 2) ? 4 : 0);
+
+ while (p1_off < p1->num_objects * p1_step &&
+ p2_off < p2->num_objects * p2_step)
+ {
+ int cmp = hashcmp(p1_base + p1_off, p2_base + p2_off);
+ /* cmp ~ p1 - p2 */
+ if (cmp == 0) {
+ ret++;
+ p1_off += p1_step;
+ p2_off += p2_step;
+ continue;
+ }
+ if (cmp < 0) { /* p1 has the object, p2 doesn't */
+ p1_off += p1_step;
+ } else { /* p2 has the object, p1 doesn't */
+ p2_off += p2_step;
+ }
+ }
+ return ret;
+}
+
+/* another O(n^2) function ... */
+static size_t get_pack_redundancy(struct pack_list *pl)
+{
+ struct pack_list *subset;
+ size_t ret = 0;
+
+ if (!pl)
+ return 0;
+
+ while ((subset = pl->next)) {
+ while (subset) {
+ ret += sizeof_union(pl->pack, subset->pack);
+ subset = subset->next;
+ }
+ pl = pl->next;
+ }
+ return ret;
+}
+
+static inline off_t pack_set_bytecount(struct pack_list *pl)
+{
+ off_t ret = 0;
+ while (pl) {
+ ret += pl->pack->pack_size;
+ ret += pl->pack->index_size;
+ pl = pl->next;
+ }
+ return ret;
+}
+
+static int cmp_remaining_objects(const void *a, const void *b)
+{
+ struct pack_list *pl_a = *((struct pack_list **)a);
+ struct pack_list *pl_b = *((struct pack_list **)b);
+
+ if (pl_a->remaining_objects->size == pl_b->remaining_objects->size) {
+ /* have the same remaining_objects, big pack first */
+ if (pl_a->all_objects_size == pl_b->all_objects_size)
+ return 0;
+ else if (pl_a->all_objects_size < pl_b->all_objects_size)
+ return 1;
+ else
+ return -1;
+ } else if (pl_a->remaining_objects->size < pl_b->remaining_objects->size) {
+ /* sort by remaining objects, more objects first */
+ return 1;
+ } else {
+ return -1;
+ }
+}
+
+/* Sort pack_list, greater size of remaining_objects first */
+static void sort_pack_list(struct pack_list **pl)
+{
+ struct pack_list **ary, *p;
+ int i;
+ size_t n = pack_list_size(*pl);
+
+ if (n < 2)
+ return;
+
+ /* prepare an array of packed_list for easier sorting */
+ CALLOC_ARRAY(ary, n);
+ for (n = 0, p = *pl; p; p = p->next)
+ ary[n++] = p;
+
+ QSORT(ary, n, cmp_remaining_objects);
+
+ /* link them back again */
+ for (i = 0; i < n - 1; i++)
+ ary[i]->next = ary[i + 1];
+ ary[n - 1]->next = NULL;
+ *pl = ary[0];
+
+ free(ary);
+}
+
+
+static void minimize(struct pack_list **min)
+{
+ struct pack_list *pl, *unique = NULL, *non_unique = NULL;
+ struct llist *missing, *unique_pack_objects;
+
+ pl = local_packs;
+ while (pl) {
+ if (pl->unique_objects->size)
+ pack_list_insert(&unique, pl);
+ else
+ pack_list_insert(&non_unique, pl);
+ pl = pl->next;
+ }
+ /* find out which objects are missing from the set of unique packs */
+ missing = llist_copy(all_objects);
+ pl = unique;
+ while (pl) {
+ llist_sorted_difference_inplace(missing, pl->remaining_objects);
+ pl = pl->next;
+ }
+
+ *min = unique;
+
+ /* return if there are no objects missing from the unique set */
+ if (missing->size == 0) {
+ free(missing);
+ return;
+ }
+
+ unique_pack_objects = llist_copy(all_objects);
+ llist_sorted_difference_inplace(unique_pack_objects, missing);
+
+ /* remove unique pack objects from the non_unique packs */
+ pl = non_unique;
+ while (pl) {
+ llist_sorted_difference_inplace(pl->remaining_objects, unique_pack_objects);
+ pl = pl->next;
+ }
+
+ while (non_unique) {
+ /* sort the non_unique packs, greater size of remaining_objects first */
+ sort_pack_list(&non_unique);
+ if (non_unique->remaining_objects->size == 0)
+ break;
+
+ pack_list_insert(min, non_unique);
+
+ for (pl = non_unique->next; pl && pl->remaining_objects->size > 0; pl = pl->next)
+ llist_sorted_difference_inplace(pl->remaining_objects, non_unique->remaining_objects);
+
+ non_unique = non_unique->next;
+ }
+}
+
+static void load_all_objects(void)
+{
+ struct pack_list *pl = local_packs;
+ struct llist_item *hint, *l;
+
+ llist_init(&all_objects);
+
+ while (pl) {
+ hint = NULL;
+ l = pl->remaining_objects->front;
+ while (l) {
+ hint = llist_insert_sorted_unique(all_objects,
+ &l->oid, hint);
+ l = l->next;
+ }
+ pl = pl->next;
+ }
+ /* remove objects present in remote packs */
+ pl = altodb_packs;
+ while (pl) {
+ llist_sorted_difference_inplace(all_objects, pl->remaining_objects);
+ pl = pl->next;
+ }
+}
+
+/* this scales like O(n^2) */
+static void cmp_local_packs(void)
+{
+ struct pack_list *subset, *pl = local_packs;
+
+ /* only one packfile */
+ if (!pl->next) {
+ llist_init(&pl->unique_objects);
+ return;
+ }
+
+ while ((subset = pl)) {
+ while ((subset = subset->next))
+ cmp_two_packs(pl, subset);
+ pl = pl->next;
+ }
+}
+
+static void scan_alt_odb_packs(void)
+{
+ struct pack_list *local, *alt;
+
+ alt = altodb_packs;
+ while (alt) {
+ local = local_packs;
+ while (local) {
+ llist_sorted_difference_inplace(local->remaining_objects,
+ alt->remaining_objects);
+ local = local->next;
+ }
+ alt = alt->next;
+ }
+}
+
+static struct pack_list * add_pack(struct packed_git *p)
+{
+ struct pack_list l;
+ size_t off = 0, step;
+ const unsigned char *base;
+
+ if (!p->pack_local && !(alt_odb || verbose))
+ return NULL;
+
+ l.pack = p;
+ llist_init(&l.remaining_objects);
+
+ if (open_pack_index(p))
+ return NULL;
+
+ base = p->index_data;
+ base += 256 * 4 + ((p->index_version < 2) ? 4 : 8);
+ step = the_hash_algo->rawsz + ((p->index_version < 2) ? 4 : 0);
+ while (off < p->num_objects * step) {
+ llist_insert_back(l.remaining_objects, base + off);
+ off += step;
+ }
+ l.all_objects_size = l.remaining_objects->size;
+ l.unique_objects = NULL;
+ if (p->pack_local)
+ return pack_list_insert(&local_packs, &l);
+ else
+ return pack_list_insert(&altodb_packs, &l);
+}
+
+static struct pack_list * add_pack_file(const char *filename)
+{
+ struct packed_git *p = get_all_packs(the_repository);
+
+ if (strlen(filename) < 40)
+ die("Bad pack filename: %s", filename);
+
+ while (p) {
+ if (strstr(p->pack_name, filename))
+ return add_pack(p);
+ p = p->next;
+ }
+ die("Filename %s not found in packed_git", filename);
+}
+
+static void load_all(void)
+{
+ struct packed_git *p = get_all_packs(the_repository);
+
+ while (p) {
+ add_pack(p);
+ p = p->next;
+ }
+}
+
+int cmd_pack_redundant(int argc, const char **argv, const char *prefix)
+{
+ int i;
+ int i_still_use_this = 0;
+ struct pack_list *min = NULL, *red, *pl;
+ struct llist *ignore;
+ struct object_id *oid;
+ char buf[GIT_MAX_HEXSZ + 2]; /* hex hash + \n + \0 */
+
+ if (argc == 2 && !strcmp(argv[1], "-h"))
+ usage(pack_redundant_usage);
+
+ for (i = 1; i < argc; i++) {
+ const char *arg = argv[i];
+ if (!strcmp(arg, "--")) {
+ i++;
+ break;
+ }
+ if (!strcmp(arg, "--all")) {
+ load_all_packs = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--verbose")) {
+ verbose = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--alt-odb")) {
+ alt_odb = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--i-still-use-this")) {
+ i_still_use_this = 1;
+ continue;
+ }
+ if (*arg == '-')
+ usage(pack_redundant_usage);
+ else
+ break;
+ }
+
+ if (!i_still_use_this) {
+ fputs(_("'git pack-redundant' is nominated for removal.\n"
+ "If you still use this command, please add an extra\n"
+ "option, '--i-still-use-this', on the command line\n"
+ "and let us know you still use it by sending an e-mail\n"
+ "to <git@vger.kernel.org>. Thanks.\n"), stderr);
+ }
+
+ if (load_all_packs)
+ load_all();
+ else
+ while (*(argv + i) != NULL)
+ add_pack_file(*(argv + i++));
+
+ if (!local_packs)
+ die("Zero packs found!");
+
+ load_all_objects();
+
+ if (alt_odb)
+ scan_alt_odb_packs();
+
+ /* ignore objects given on stdin */
+ llist_init(&ignore);
+ if (!isatty(0)) {
+ while (fgets(buf, sizeof(buf), stdin)) {
+ oid = xmalloc(sizeof(*oid));
+ if (get_oid_hex(buf, oid))
+ die("Bad object ID on stdin: %s", buf);
+ llist_insert_sorted_unique(ignore, oid, NULL);
+ }
+ }
+ llist_sorted_difference_inplace(all_objects, ignore);
+ pl = local_packs;
+ while (pl) {
+ llist_sorted_difference_inplace(pl->remaining_objects, ignore);
+ pl = pl->next;
+ }
+
+ cmp_local_packs();
+
+ minimize(&min);
+
+ if (verbose) {
+ fprintf(stderr, "There are %lu packs available in alt-odbs.\n",
+ (unsigned long)pack_list_size(altodb_packs));
+ fprintf(stderr, "The smallest (bytewise) set of packs is:\n");
+ pl = min;
+ while (pl) {
+ fprintf(stderr, "\t%s\n", pl->pack->pack_name);
+ pl = pl->next;
+ }
+ fprintf(stderr, "containing %lu duplicate objects "
+ "with a total size of %lukb.\n",
+ (unsigned long)get_pack_redundancy(min),
+ (unsigned long)pack_set_bytecount(min)/1024);
+ fprintf(stderr, "A total of %lu unique objects were considered.\n",
+ (unsigned long)all_objects->size);
+ fprintf(stderr, "Redundant packs (with indexes):\n");
+ }
+ pl = red = pack_list_difference(local_packs, min);
+ while (pl) {
+ printf("%s\n%s\n",
+ sha1_pack_index_name(pl->pack->hash),
+ pl->pack->pack_name);
+ pl = pl->next;
+ }
+ if (verbose)
+ fprintf(stderr, "%luMB of redundant packs in total.\n",
+ (unsigned long)pack_set_bytecount(red)/(1024*1024));
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 04:37:46 +0000