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-rw-r--r--pack-redundant.c695
1 files changed, 0 insertions, 695 deletions
diff --git a/pack-redundant.c b/pack-redundant.c
deleted file mode 100644
index f5cd0ac59e..0000000000
--- a/pack-redundant.c
+++ /dev/null
@@ -1,695 +0,0 @@
-/*
-*
-* Copyright 2005, Lukas Sandstrom <lukass@etek.chalmers.se>
-*
-* This file is licensed under the GPL v2.
-*
-*/
-
-#include "cache.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;
- const unsigned char *sha1;
-};
-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 *all_objects;
-} *local_packs = NULL, *altodb_packs = NULL;
-
-struct pll {
- struct pll *next;
- struct pack_list *pl;
-};
-
-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;
- if ( free_nodes ) {
- new = free_nodes;
- free_nodes = free_nodes->next;
- } else {
- int i = 1;
- new = xmalloc(sizeof(struct llist_item) * BLKSIZE);
- for(;i < BLKSIZE; i++) {
- llist_item_put(&new[i]);
- }
- }
- return new;
-}
-
-static void llist_free(struct llist *list)
-{
- while((list->back = list->front)) {
- list->front = list->front->next;
- llist_item_put(list->back);
- }
- free(list);
-}
-
-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, *old, *prev;
-
- llist_init(&ret);
-
- if ((ret->size = list->size) == 0)
- return ret;
-
- new = ret->front = llist_item_get();
- new->sha1 = list->front->sha1;
-
- old = list->front->next;
- while (old) {
- prev = new;
- new = llist_item_get();
- prev->next = new;
- new->sha1 = old->sha1;
- old = old->next;
- }
- new->next = NULL;
- ret->back = new;
-
- return ret;
-}
-
-static inline struct llist_item *llist_insert(struct llist *list,
- struct llist_item *after,
- const unsigned char *sha1)
-{
- struct llist_item *new = llist_item_get();
- new->sha1 = sha1;
- new->next = NULL;
-
- if (after != NULL) {
- new->next = after->next;
- after->next = new;
- if (after == list->back)
- list->back = new;
- } else {/* insert in front */
- if (list->size == 0)
- list->back = new;
- else
- new->next = list->front;
- list->front = new;
- }
- list->size++;
- return new;
-}
-
-static inline struct llist_item *llist_insert_back(struct llist *list,
- const unsigned char *sha1)
-{
- return llist_insert(list, list->back, sha1);
-}
-
-static inline struct llist_item *llist_insert_sorted_unique(struct llist *list,
- const unsigned char *sha1, struct llist_item *hint)
-{
- struct llist_item *prev = NULL, *l;
-
- l = (hint == NULL) ? list->front : hint;
- while (l) {
- int cmp = hashcmp(l->sha1, sha1);
- if (cmp > 0) { /* we insert before this entry */
- return llist_insert(list, prev, sha1);
- }
- if(!cmp) { /* already exists */
- return l;
- }
- prev = l;
- l = l->next;
- }
- /* insert at the end */
- return llist_insert_back(list, sha1);
-}
-
-/* returns a pointer to an item in front of sha1 */
-static inline struct llist_item * llist_sorted_remove(struct llist *list, const unsigned char *sha1, struct llist_item *hint)
-{
- struct llist_item *prev, *l;
-
-redo_from_start:
- l = (hint == NULL) ? list->front : hint;
- prev = NULL;
- while (l) {
- int cmp = hashcmp(l->sha1, sha1);
- if (cmp > 0) /* not in list, since sorted */
- return prev;
- if(!cmp) { /* found */
- if (prev == NULL) {
- 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->sha1, 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 == NULL)
- 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)
-{
- unsigned long 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;
-
- 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 = (p1->pack->index_version < 2) ? 24 : 20;
- p2_step = (p2->pack->index_version < 2) ? 24 : 20;
-
- while (p1_off < p1->pack->num_objects * p1_step &&
- p2_off < p2->pack->num_objects * p2_step)
- {
- 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 void pll_free(struct pll *l)
-{
- struct pll *old;
- struct pack_list *opl;
-
- while (l) {
- old = l;
- while (l->pl) {
- opl = l->pl;
- l->pl = opl->next;
- free(opl);
- }
- l = l->next;
- free(old);
- }
-}
-
-/* all the permutations have to be free()d at the same time,
- * since they refer to each other
- */
-static struct pll * get_permutations(struct pack_list *list, int n)
-{
- struct pll *subset, *ret = NULL, *new_pll = NULL, *pll;
-
- if (list == NULL || pack_list_size(list) < n || n == 0)
- return NULL;
-
- if (n == 1) {
- while (list) {
- new_pll = xmalloc(sizeof(pll));
- new_pll->pl = NULL;
- pack_list_insert(&new_pll->pl, list);
- new_pll->next = ret;
- ret = new_pll;
- list = list->next;
- }
- return ret;
- }
-
- while (list->next) {
- subset = get_permutations(list->next, n - 1);
- while (subset) {
- new_pll = xmalloc(sizeof(pll));
- new_pll->pl = subset->pl;
- pack_list_insert(&new_pll->pl, list);
- new_pll->next = ret;
- ret = new_pll;
- subset = subset->next;
- }
- list = list->next;
- }
- return ret;
-}
-
-static int is_superset(struct pack_list *pl, struct llist *list)
-{
- struct llist *diff;
-
- diff = llist_copy(list);
-
- while (pl) {
- llist_sorted_difference_inplace(diff, pl->all_objects);
- if (diff->size == 0) { /* we're done */
- llist_free(diff);
- return 1;
- }
- pl = pl->next;
- }
- llist_free(diff);
- return 0;
-}
-
-static size_t sizeof_union(struct packed_git *p1, struct packed_git *p2)
-{
- size_t ret = 0;
- unsigned long p1_off = 0, p2_off = 0, p1_step, p2_step;
- const unsigned char *p1_base, *p2_base;
-
- 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 = (p1->index_version < 2) ? 24 : 20;
- p2_step = (p2->index_version < 2) ? 24 : 20;
-
- 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 == NULL)
- 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 void minimize(struct pack_list **min)
-{
- struct pack_list *pl, *unique = NULL,
- *non_unique = NULL, *min_perm = NULL;
- struct pll *perm, *perm_all, *perm_ok = NULL, *new_perm;
- struct llist *missing;
- off_t min_perm_size = 0, perm_size;
- int n;
-
- 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->all_objects);
- pl = pl->next;
- }
-
- /* return if there are no objects missing from the unique set */
- if (missing->size == 0) {
- *min = unique;
- return;
- }
-
- /* find the permutations which contain all missing objects */
- for (n = 1; n <= pack_list_size(non_unique) && !perm_ok; n++) {
- perm_all = perm = get_permutations(non_unique, n);
- while (perm) {
- if (is_superset(perm->pl, missing)) {
- new_perm = xmalloc(sizeof(struct pll));
- memcpy(new_perm, perm, sizeof(struct pll));
- new_perm->next = perm_ok;
- perm_ok = new_perm;
- }
- perm = perm->next;
- }
- if (perm_ok)
- break;
- pll_free(perm_all);
- }
- if (perm_ok == NULL)
- die("Internal error: No complete sets found!\n");
-
- /* find the permutation with the smallest size */
- perm = perm_ok;
- while (perm) {
- perm_size = pack_set_bytecount(perm->pl);
- if (!min_perm_size || min_perm_size > perm_size) {
- min_perm_size = perm_size;
- min_perm = perm->pl;
- }
- perm = perm->next;
- }
- *min = min_perm;
- /* add the unique packs to the list */
- pl = unique;
- while(pl) {
- pack_list_insert(min, pl);
- pl = pl->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->all_objects->front;
- while (l) {
- hint = llist_insert_sorted_unique(all_objects,
- l->sha1, 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->all_objects);
- pl = pl->next;
- }
-}
-
-/* this scales like O(n^2) */
-static void cmp_local_packs(void)
-{
- struct pack_list *subset, *pl = local_packs;
-
- 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->unique_objects,
- alt->all_objects);
- local = local->next;
- }
- llist_sorted_difference_inplace(all_objects, alt->all_objects);
- alt = alt->next;
- }
-}
-
-static struct pack_list * add_pack(struct packed_git *p)
-{
- struct pack_list l;
- unsigned long off = 0, step;
- const unsigned char *base;
-
- if (!p->pack_local && !(alt_odb || verbose))
- return NULL;
-
- l.pack = p;
- llist_init(&l.all_objects);
-
- if (open_pack_index(p))
- return NULL;
-
- base = p->index_data;
- base += 256 * 4 + ((p->index_version < 2) ? 4 : 8);
- step = (p->index_version < 2) ? 24 : 20;
- while (off < p->num_objects * step) {
- llist_insert_back(l.all_objects, base + off);
- off += step;
- }
- /* this list will be pruned in cmp_two_packs later */
- l.unique_objects = llist_copy(l.all_objects);
- 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(char *filename)
-{
- struct packed_git *p = packed_git;
-
- if (strlen(filename) < 40)
- die("Bad pack filename: %s\n", filename);
-
- while (p) {
- if (strstr(p->pack_name, filename))
- return add_pack(p);
- p = p->next;
- }
- die("Filename %s not found in packed_git\n", filename);
-}
-
-static void load_all(void)
-{
- struct packed_git *p = packed_git;
-
- while (p) {
- add_pack(p);
- p = p->next;
- }
-}
-
-int main(int argc, char **argv)
-{
- int i;
- struct pack_list *min, *red, *pl;
- struct llist *ignore;
- unsigned char *sha1;
- char buf[42]; /* 40 byte sha1 + \n + \0 */
-
- setup_git_directory();
-
- 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(*arg == '-')
- usage(pack_redundant_usage);
- else
- break;
- }
-
- prepare_packed_git();
-
- if (load_all_packs)
- load_all();
- else
- while (*(argv + i) != NULL)
- add_pack_file(*(argv + i++));
-
- if (local_packs == NULL)
- die("Zero packs found!\n");
-
- load_all_objects();
-
- cmp_local_packs();
- if (alt_odb)
- scan_alt_odb_packs();
-
- /* ignore objects given on stdin */
- llist_init(&ignore);
- if (!isatty(0)) {
- while (fgets(buf, sizeof(buf), stdin)) {
- sha1 = xmalloc(20);
- if (get_sha1_hex(buf, sha1))
- die("Bad sha1 on stdin: %s", buf);
- llist_insert_sorted_unique(ignore, sha1, NULL);
- }
- }
- llist_sorted_difference_inplace(all_objects, ignore);
- pl = local_packs;
- while (pl) {
- llist_sorted_difference_inplace(pl->unique_objects, ignore);
- pl = pl->next;
- }
-
- 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->sha1),
- 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 2.25.1) at 2024-12-17 21:53:00 +0000