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Diffstat (limited to 'third_party/git/pack-objects.h')
| -rw-r--r-- | third_party/git/pack-objects.h | 451 |
1 files changed, 0 insertions, 451 deletions
diff --git a/third_party/git/pack-objects.h b/third_party/git/pack-objects.h deleted file mode 100644 index 9d88e3e518f0..000000000000 --- a/third_party/git/pack-objects.h +++ /dev/null @@ -1,451 +0,0 @@ -#ifndef PACK_OBJECTS_H -#define PACK_OBJECTS_H - -#include "object-store.h" -#include "thread-utils.h" -#include "pack.h" - -struct repository; - -#define DEFAULT_DELTA_CACHE_SIZE (256 * 1024 * 1024) - -#define OE_DFS_STATE_BITS 2 -#define OE_DEPTH_BITS 12 -#define OE_IN_PACK_BITS 10 -#define OE_Z_DELTA_BITS 20 -/* - * Note that oe_set_size() becomes expensive when the given size is - * above this limit. Don't lower it too much. - */ -#define OE_SIZE_BITS 31 -#define OE_DELTA_SIZE_BITS 23 - -/* - * State flags for depth-first search used for analyzing delta cycles. - * - * The depth is measured in delta-links to the base (so if A is a delta - * against B, then A has a depth of 1, and B a depth of 0). - */ -enum dfs_state { - DFS_NONE = 0, - DFS_ACTIVE, - DFS_DONE, - DFS_NUM_STATES -}; - -/* - * The size of struct nearly determines pack-objects's memory - * consumption. This struct is packed tight for that reason. When you - * add or reorder something in this struct, think a bit about this. - * - * basic object info - * ----------------- - * idx.oid is filled up before delta searching starts. idx.crc32 is - * only valid after the object is written out and will be used for - * generating the index. idx.offset will be both gradually set and - * used in writing phase (base objects get offset first, then deltas - * refer to them) - * - * "size" is the uncompressed object size. Compressed size of the raw - * data for an object in a pack is not stored anywhere but is computed - * and made available when reverse .idx is made. Note that when a - * delta is reused, "size" is the uncompressed _delta_ size, not the - * canonical one after the delta has been applied. - * - * "hash" contains a path name hash which is used for sorting the - * delta list and also during delta searching. Once prepare_pack() - * returns it's no longer needed. - * - * source pack info - * ---------------- - * The (in_pack, in_pack_offset) tuple contains the location of the - * object in the source pack. in_pack_header_size allows quickly - * skipping the header and going straight to the zlib stream. - * - * "type" and "in_pack_type" both describe object type. in_pack_type - * may contain a delta type, while type is always the canonical type. - * - * deltas - * ------ - * Delta links (delta, delta_child and delta_sibling) are created to - * reflect that delta graph from the source pack then updated or added - * during delta searching phase when we find better deltas. - * - * delta_child and delta_sibling are last needed in - * compute_write_order(). "delta" and "delta_size" must remain valid - * at object writing phase in case the delta is not cached. - * - * If a delta is cached in memory and is compressed, delta_data points - * to the data and z_delta_size contains the compressed size. If it's - * uncompressed [1], z_delta_size must be zero. delta_size is always - * the uncompressed size and must be valid even if the delta is not - * cached. - * - * [1] during try_delta phase we don't bother with compressing because - * the delta could be quickly replaced with a better one. - */ -struct object_entry { - struct pack_idx_entry idx; - void *delta_data; /* cached delta (uncompressed) */ - off_t in_pack_offset; - uint32_t hash; /* name hint hash */ - unsigned size_:OE_SIZE_BITS; - unsigned size_valid:1; - uint32_t delta_idx; /* delta base object */ - uint32_t delta_child_idx; /* deltified objects who bases me */ - uint32_t delta_sibling_idx; /* other deltified objects who - * uses the same base as me - */ - unsigned delta_size_:OE_DELTA_SIZE_BITS; /* delta data size (uncompressed) */ - unsigned delta_size_valid:1; - unsigned char in_pack_header_size; - unsigned in_pack_idx:OE_IN_PACK_BITS; /* already in pack */ - unsigned z_delta_size:OE_Z_DELTA_BITS; - unsigned type_valid:1; - unsigned no_try_delta:1; - unsigned type_:TYPE_BITS; - unsigned in_pack_type:TYPE_BITS; /* could be delta */ - - unsigned preferred_base:1; /* - * we do not pack this, but is available - * to be used as the base object to delta - * objects against. - */ - unsigned tagged:1; /* near the very tip of refs */ - unsigned filled:1; /* assigned write-order */ - unsigned dfs_state:OE_DFS_STATE_BITS; - unsigned depth:OE_DEPTH_BITS; - unsigned ext_base:1; /* delta_idx points outside packlist */ - - /* - * pahole results on 64-bit linux (gcc and clang) - * - * size: 80, bit_padding: 9 bits - * - * and on 32-bit (gcc) - * - * size: 76, bit_padding: 9 bits - */ -}; - -struct packing_data { - struct repository *repo; - struct object_entry *objects; - uint32_t nr_objects, nr_alloc; - - int32_t *index; - uint32_t index_size; - - unsigned int *in_pack_pos; - unsigned long *delta_size; - - /* - * Only one of these can be non-NULL and they have different - * sizes. if in_pack_by_idx is allocated, oe_in_pack() returns - * the pack of an object using in_pack_idx field. If not, - * in_pack[] array is used the same way as in_pack_pos[] - */ - struct packed_git **in_pack_by_idx; - struct packed_git **in_pack; - - /* - * During packing with multiple threads, protect the in-core - * object database from concurrent accesses. - */ - pthread_mutex_t odb_lock; - - /* - * This list contains entries for bases which we know the other side - * has (e.g., via reachability bitmaps), but which aren't in our - * "objects" list. - */ - struct object_entry *ext_bases; - uint32_t nr_ext, alloc_ext; - - uintmax_t oe_size_limit; - uintmax_t oe_delta_size_limit; - - /* delta islands */ - unsigned int *tree_depth; - unsigned char *layer; -}; - -void prepare_packing_data(struct repository *r, struct packing_data *pdata); - -/* Protect access to object database */ -static inline void packing_data_lock(struct packing_data *pdata) -{ - pthread_mutex_lock(&pdata->odb_lock); -} -static inline void packing_data_unlock(struct packing_data *pdata) -{ - pthread_mutex_unlock(&pdata->odb_lock); -} - -struct object_entry *packlist_alloc(struct packing_data *pdata, - const struct object_id *oid); - -struct object_entry *packlist_find(struct packing_data *pdata, - const struct object_id *oid); - -static inline uint32_t pack_name_hash(const char *name) -{ - uint32_t c, hash = 0; - - if (!name) - return 0; - - /* - * 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. - */ - while ((c = *name++) != 0) { - if (isspace(c)) - continue; - hash = (hash >> 2) + (c << 24); - } - return hash; -} - -static inline enum object_type oe_type(const struct object_entry *e) -{ - return e->type_valid ? e->type_ : OBJ_BAD; -} - -static inline void oe_set_type(struct object_entry *e, - enum object_type type) -{ - if (type >= OBJ_ANY) - BUG("OBJ_ANY cannot be set in pack-objects code"); - - e->type_valid = type >= OBJ_NONE; - e->type_ = (unsigned)type; -} - -static inline unsigned int oe_in_pack_pos(const struct packing_data *pack, - const struct object_entry *e) -{ - return pack->in_pack_pos[e - pack->objects]; -} - -static inline void oe_set_in_pack_pos(const struct packing_data *pack, - const struct object_entry *e, - unsigned int pos) -{ - pack->in_pack_pos[e - pack->objects] = pos; -} - -static inline struct packed_git *oe_in_pack(const struct packing_data *pack, - const struct object_entry *e) -{ - if (pack->in_pack_by_idx) - return pack->in_pack_by_idx[e->in_pack_idx]; - else - return pack->in_pack[e - pack->objects]; -} - -void oe_map_new_pack(struct packing_data *pack); - -static inline void oe_set_in_pack(struct packing_data *pack, - struct object_entry *e, - struct packed_git *p) -{ - if (pack->in_pack_by_idx) { - if (p->index) { - e->in_pack_idx = p->index; - return; - } - /* - * We're accessing packs by index, but this pack doesn't have - * an index (e.g., because it was added since we created the - * in_pack_by_idx array). Bail to oe_map_new_pack(), which - * will convert us to using the full in_pack array, and then - * fall through to our in_pack handling. - */ - oe_map_new_pack(pack); - } - pack->in_pack[e - pack->objects] = p; -} - -static inline struct object_entry *oe_delta( - const struct packing_data *pack, - const struct object_entry *e) -{ - if (!e->delta_idx) - return NULL; - if (e->ext_base) - return &pack->ext_bases[e->delta_idx - 1]; - else - return &pack->objects[e->delta_idx - 1]; -} - -static inline void oe_set_delta(struct packing_data *pack, - struct object_entry *e, - struct object_entry *delta) -{ - if (delta) - e->delta_idx = (delta - pack->objects) + 1; - else - e->delta_idx = 0; -} - -void oe_set_delta_ext(struct packing_data *pack, - struct object_entry *e, - const struct object_id *oid); - -static inline struct object_entry *oe_delta_child( - const struct packing_data *pack, - const struct object_entry *e) -{ - if (e->delta_child_idx) - return &pack->objects[e->delta_child_idx - 1]; - return NULL; -} - -static inline void oe_set_delta_child(struct packing_data *pack, - struct object_entry *e, - struct object_entry *delta) -{ - if (delta) - e->delta_child_idx = (delta - pack->objects) + 1; - else - e->delta_child_idx = 0; -} - -static inline struct object_entry *oe_delta_sibling( - const struct packing_data *pack, - const struct object_entry *e) -{ - if (e->delta_sibling_idx) - return &pack->objects[e->delta_sibling_idx - 1]; - return NULL; -} - -static inline void oe_set_delta_sibling(struct packing_data *pack, - struct object_entry *e, - struct object_entry *delta) -{ - if (delta) - e->delta_sibling_idx = (delta - pack->objects) + 1; - else - e->delta_sibling_idx = 0; -} - -unsigned long oe_get_size_slow(struct packing_data *pack, - const struct object_entry *e); -static inline unsigned long oe_size(struct packing_data *pack, - const struct object_entry *e) -{ - if (e->size_valid) - return e->size_; - - return oe_get_size_slow(pack, e); -} - -static inline int oe_size_less_than(struct packing_data *pack, - const struct object_entry *lhs, - unsigned long rhs) -{ - if (lhs->size_valid) - return lhs->size_ < rhs; - if (rhs < pack->oe_size_limit) /* rhs < 2^x <= lhs ? */ - return 0; - return oe_get_size_slow(pack, lhs) < rhs; -} - -static inline int oe_size_greater_than(struct packing_data *pack, - const struct object_entry *lhs, - unsigned long rhs) -{ - if (lhs->size_valid) - return lhs->size_ > rhs; - if (rhs < pack->oe_size_limit) /* rhs < 2^x <= lhs ? */ - return 1; - return oe_get_size_slow(pack, lhs) > rhs; -} - -static inline void oe_set_size(struct packing_data *pack, - struct object_entry *e, - unsigned long size) -{ - if (size < pack->oe_size_limit) { - e->size_ = size; - e->size_valid = 1; - } else { - e->size_valid = 0; - if (oe_get_size_slow(pack, e) != size) - BUG("'size' is supposed to be the object size!"); - } -} - -static inline unsigned long oe_delta_size(struct packing_data *pack, - const struct object_entry *e) -{ - if (e->delta_size_valid) - return e->delta_size_; - - /* - * pack->delta_size[] can't be NULL because oe_set_delta_size() - * must have been called when a new delta is saved with - * oe_set_delta(). - * If oe_delta() returns NULL (i.e. default state, which means - * delta_size_valid is also false), then the caller must never - * call oe_delta_size(). - */ - return pack->delta_size[e - pack->objects]; -} - -static inline void oe_set_delta_size(struct packing_data *pack, - struct object_entry *e, - unsigned long size) -{ - if (size < pack->oe_delta_size_limit) { - e->delta_size_ = size; - e->delta_size_valid = 1; - } else { - packing_data_lock(pack); - if (!pack->delta_size) - ALLOC_ARRAY(pack->delta_size, pack->nr_alloc); - packing_data_unlock(pack); - - pack->delta_size[e - pack->objects] = size; - e->delta_size_valid = 0; - } -} - -static inline unsigned int oe_tree_depth(struct packing_data *pack, - struct object_entry *e) -{ - if (!pack->tree_depth) - return 0; - return pack->tree_depth[e - pack->objects]; -} - -static inline void oe_set_tree_depth(struct packing_data *pack, - struct object_entry *e, - unsigned int tree_depth) -{ - if (!pack->tree_depth) - CALLOC_ARRAY(pack->tree_depth, pack->nr_alloc); - pack->tree_depth[e - pack->objects] = tree_depth; -} - -static inline unsigned char oe_layer(struct packing_data *pack, - struct object_entry *e) -{ - if (!pack->layer) - return 0; - return pack->layer[e - pack->objects]; -} - -static inline void oe_set_layer(struct packing_data *pack, - struct object_entry *e, - unsigned char layer) -{ - if (!pack->layer) - CALLOC_ARRAY(pack->layer, pack->nr_alloc); - pack->layer[e - pack->objects] = layer; -} - -#endif |