git-tar-tree: no more void pointer arithmetic
[git.git] / pack-redundant.c
index 1519385..cd81f5a 100644 (file)
@@ -8,6 +8,8 @@
 
 #include "cache.h"
 
+#define BLKSIZE 512
+
 static const char pack_redundant_usage[] =
 "git-pack-redundant [ --verbose ] [ --alt-odb ] < --all | <.pack filename> ...>";
 
@@ -15,7 +17,7 @@ static int load_all_packs = 0, verbose = 0, alt_odb = 0;
 
 struct llist_item {
        struct llist_item *next;
-       char *sha1;
+       unsigned char *sha1;
 };
 static struct llist {
        struct llist_item *front;
@@ -33,14 +35,37 @@ static struct pack_list {
 struct pll {
        struct pll *next;
        struct pack_list *pl;
-       size_t pl_size;
 };
 
-static inline void llist_free(struct llist *list)
+static struct llist_item *free_nodes = NULL;
+
+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;
-               free(list->back);
+               llist_item_put(list->back);
        }
        free(list);
 }
@@ -62,13 +87,13 @@ static struct llist * llist_copy(struct llist *list)
        if ((ret->size = list->size) == 0)
                return ret;
 
-       new = ret->front = xmalloc(sizeof(struct llist_item));
+       new = ret->front = llist_item_get();
        new->sha1 = list->front->sha1;
 
        old = list->front->next;
        while (old) {
                prev = new;
-               new = xmalloc(sizeof(struct llist_item));
+               new = llist_item_get();
                prev->next = new;
                new->sha1 = old->sha1;
                old = old->next;
@@ -80,9 +105,10 @@ static struct llist * llist_copy(struct llist *list)
 }
 
 static inline struct llist_item * llist_insert(struct llist *list,
-                                       struct llist_item *after, char *sha1)
+                                              struct llist_item *after,
+                                              unsigned char *sha1)
 {
-       struct llist_item *new = xmalloc(sizeof(struct llist_item));
+       struct llist_item *new = llist_item_get();
        new->sha1 = sha1;
        new->next = NULL;
 
@@ -102,13 +128,12 @@ static inline struct llist_item * llist_insert(struct llist *list,
        return new;
 }
 
-static inline struct llist_item * llist_insert_back(struct llist *list, char *sha1)
+static inline struct llist_item *llist_insert_back(struct llist *list, unsigned char *sha1)
 {
        return llist_insert(list, list->back, sha1);
 }
 
-static inline struct llist_item * llist_insert_sorted_unique(struct llist *list,
-                                       char *sha1, struct llist_item *hint)
+static inline struct llist_item *llist_insert_sorted_unique(struct llist *list, unsigned char *sha1, struct llist_item *hint)
 {
        struct llist_item *prev = NULL, *l;
 
@@ -129,8 +154,7 @@ static inline struct llist_item * llist_insert_sorted_unique(struct llist *list,
 }
 
 /* returns a pointer to an item in front of sha1 */
-static inline struct llist_item * llist_sorted_remove(struct llist *list, char *sha1,
-                                              struct llist_item *hint)
+static inline struct llist_item * llist_sorted_remove(struct llist *list, const unsigned char *sha1, struct llist_item *hint)
 {
        struct llist_item *prev, *l;
 
@@ -153,7 +177,7 @@ redo_from_start:
                                prev->next = l->next;
                        if (l == list->back)
                                list->back = prev;
-                       free(l);
+                       llist_item_put(l);
                        list->size--;
                        return prev;
                }
@@ -198,10 +222,11 @@ static inline size_t pack_list_size(struct pack_list *pl)
        return ret;
 }
 
-static struct pack_list * pack_list_difference(struct pack_list *A,
-                                       struct pack_list *B)
+static struct pack_list * pack_list_difference(const struct pack_list *A,
+                                              const struct pack_list *B)
 {
-       struct pack_list *ret, *pl;
+       struct pack_list *ret;
+       const struct pack_list *pl;
 
        if (A == NULL)
                return NULL;
@@ -250,77 +275,58 @@ static void cmp_two_packs(struct pack_list *p1, struct pack_list *p2)
        }
 }
 
-static void pll_insert(struct pll **pll, struct pll **hint_table)
+static void pll_free(struct pll *l)
 {
-       struct pll *prev;
-       int i = (*pll)->pl_size - 1;
-
-       if (hint_table[i] == NULL) {
-               hint_table[i--] = *pll;
-               for (; i >= 0; --i) {
-                       if (hint_table[i] != NULL)
-                               break;
+       struct pll *old;
+       struct pack_list *opl;
+
+       while (l) {
+               old = l;
+               while (l->pl) {
+                       opl = l->pl;
+                       l->pl = opl->next;
+                       free(opl);
                }
-               if (hint_table[i] == NULL) /* no elements in list */
-                       die("Why did this happen?");
+               l = l->next;
+               free(old);
        }
-
-       prev = hint_table[i];
-       while (prev->next && prev->next->pl_size < (*pll)->pl_size)
-               prev = prev->next;
-
-       (*pll)->next = prev->next;
-       prev->next = *pll;
 }
 
 /* all the permutations have to be free()d at the same time,
  * since they refer to each other
  */
-static struct pll * get_all_permutations(struct pack_list *list)
+static struct pll * get_permutations(struct pack_list *list, int n)
 {
-       struct pll *subset, *pll, *new_pll = NULL; /*silence warning*/
-       static struct pll **hint = NULL;
-       if (hint == NULL)
-               hint = xcalloc(pack_list_size(list), sizeof(struct pll *));
-               
-       if (list == NULL)
+       struct pll *subset, *ret = NULL, *new_pll = NULL, *pll;
+
+       if (list == NULL || pack_list_size(list) < n || n == 0)
                return NULL;
 
-       if (list->next == NULL) {
-               new_pll = xmalloc(sizeof(struct pll));
-               hint[0] = new_pll;
-               new_pll->next = NULL;
-               new_pll->pl = list;
-               new_pll->pl_size = 1;
-               return new_pll;
+       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;
        }
 
-       pll = subset = get_all_permutations(list->next);
-       while (pll) {
-               if (pll->pl->pack == list->pack) {
-                       pll = pll->next;
-                       continue;
+       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;
                }
-               new_pll = xmalloc(sizeof(struct pll));
-
-               new_pll->pl = xmalloc(sizeof(struct pack_list));
-               memcpy(new_pll->pl, list, sizeof(struct pack_list));
-               new_pll->pl->next = pll->pl;
-               new_pll->pl_size = pll->pl_size + 1;
-               
-               pll_insert(&new_pll, hint);
-
-               pll = pll->next;
-       }
-       /* add ourself */
-       new_pll = xmalloc(sizeof(struct pll));
-       new_pll->pl = xmalloc(sizeof(struct pack_list));
-       memcpy(new_pll->pl, list, sizeof(struct pack_list));
-       new_pll->pl->next = NULL;
-       new_pll->pl_size = 1;
-       pll_insert(&new_pll, hint);
-
-       return hint[0];
+               list = list->next;
+       }
+       return ret;
 }
 
 static int is_superset(struct pack_list *pl, struct llist *list)
@@ -330,8 +336,7 @@ static int is_superset(struct pack_list *pl, struct llist *list)
        diff = llist_copy(list);
 
        while (pl) {
-               llist_sorted_difference_inplace(diff,
-                                               pl->all_objects);
+               llist_sorted_difference_inplace(diff, pl->all_objects);
                if (diff->size == 0) { /* we're done */
                        llist_free(diff);
                        return 1;
@@ -409,6 +414,7 @@ static void minimize(struct pack_list **min)
        struct pll *perm, *perm_all, *perm_ok = NULL, *new_perm;
        struct llist *missing;
        size_t min_perm_size = (size_t)-1, perm_size;
+       int n;
 
        pl = local_packs;
        while (pl) {
@@ -422,8 +428,7 @@ static void minimize(struct pack_list **min)
        missing = llist_copy(all_objects);
        pl = unique;
        while (pl) {
-               llist_sorted_difference_inplace(missing,
-                                               pl->all_objects);
+               llist_sorted_difference_inplace(missing, pl->all_objects);
                pl = pl->next;
        }
 
@@ -434,19 +439,21 @@ static void minimize(struct pack_list **min)
        }
 
        /* find the permutations which contain all missing objects */
-       perm_all = perm = get_all_permutations(non_unique);
-       while (perm) {
-               if (perm_ok && perm->pl_size > perm_ok->pl_size)
-                       break; /* ignore all larger permutations */
-               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;
+       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;
                }
-               perm = perm->next;
+               if (perm_ok)
+                       break;
+               pll_free(perm_all);
        }
-       
        if (perm_ok == NULL)
                die("Internal error: No complete sets found!\n");
 
@@ -473,12 +480,10 @@ static void load_all_objects(void)
 {
        struct pack_list *pl = local_packs;
        struct llist_item *hint, *l;
-       int i;
 
        llist_init(&all_objects);
 
        while (pl) {
-               i = 0;
                hint = NULL;
                l = pl->all_objects->front;
                while (l) {
@@ -520,6 +525,7 @@ static void scan_alt_odb_packs(void)
                                                        alt->all_objects);
                        local = local->next;
                }
+               llist_sorted_difference_inplace(all_objects, alt->all_objects);
                alt = alt->next;
        }
 }
@@ -579,6 +585,11 @@ 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];
@@ -621,6 +632,23 @@ int main(int argc, char **argv)
        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) {
@@ -647,6 +675,9 @@ int main(int argc, char **argv)
                       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;
 }