cache.hon commit simple euristic for further free packing improvements (4e8da19)
   1#ifndef CACHE_H
   2#define CACHE_H
   3
   4#include "git-compat-util.h"
   5
   6#include SHA1_HEADER
   7#include <zlib.h>
   8
   9#if ZLIB_VERNUM < 0x1200
  10#define deflateBound(c,s)  ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
  11#endif
  12
  13#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
  14#define DTYPE(de)       ((de)->d_type)
  15#else
  16#undef DT_UNKNOWN
  17#undef DT_DIR
  18#undef DT_REG
  19#undef DT_LNK
  20#define DT_UNKNOWN      0
  21#define DT_DIR          1
  22#define DT_REG          2
  23#define DT_LNK          3
  24#define DTYPE(de)       DT_UNKNOWN
  25#endif
  26
  27/*
  28 * Intensive research over the course of many years has shown that
  29 * port 9418 is totally unused by anything else. Or
  30 *
  31 *      Your search - "port 9418" - did not match any documents.
  32 *
  33 * as www.google.com puts it.
  34 *
  35 * This port has been properly assigned for git use by IANA:
  36 * git (Assigned-9418) [I06-050728-0001].
  37 *
  38 *      git  9418/tcp   git pack transfer service
  39 *      git  9418/udp   git pack transfer service
  40 *
  41 * with Linus Torvalds <torvalds@osdl.org> as the point of
  42 * contact. September 2005.
  43 *
  44 * See http://www.iana.org/assignments/port-numbers
  45 */
  46#define DEFAULT_GIT_PORT 9418
  47
  48/*
  49 * Basic data structures for the directory cache
  50 */
  51
  52#define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
  53struct cache_header {
  54        unsigned int hdr_signature;
  55        unsigned int hdr_version;
  56        unsigned int hdr_entries;
  57};
  58
  59/*
  60 * The "cache_time" is just the low 32 bits of the
  61 * time. It doesn't matter if it overflows - we only
  62 * check it for equality in the 32 bits we save.
  63 */
  64struct cache_time {
  65        unsigned int sec;
  66        unsigned int nsec;
  67};
  68
  69/*
  70 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
  71 * Again - this is just a (very strong in practice) heuristic that
  72 * the inode hasn't changed.
  73 *
  74 * We save the fields in big-endian order to allow using the
  75 * index file over NFS transparently.
  76 */
  77struct cache_entry {
  78        struct cache_time ce_ctime;
  79        struct cache_time ce_mtime;
  80        unsigned int ce_dev;
  81        unsigned int ce_ino;
  82        unsigned int ce_mode;
  83        unsigned int ce_uid;
  84        unsigned int ce_gid;
  85        unsigned int ce_size;
  86        unsigned char sha1[20];
  87        unsigned short ce_flags;
  88        char name[FLEX_ARRAY]; /* more */
  89};
  90
  91#define CE_NAMEMASK  (0x0fff)
  92#define CE_STAGEMASK (0x3000)
  93#define CE_UPDATE    (0x4000)
  94#define CE_VALID     (0x8000)
  95#define CE_STAGESHIFT 12
  96
  97#define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
  98#define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
  99#define ce_size(ce) cache_entry_size(ce_namelen(ce))
 100#define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
 101
 102#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 103static inline unsigned int create_ce_mode(unsigned int mode)
 104{
 105        if (S_ISLNK(mode))
 106                return htonl(S_IFLNK);
 107        return htonl(S_IFREG | ce_permissions(mode));
 108}
 109#define canon_mode(mode) \
 110        (S_ISREG(mode) ? (S_IFREG | ce_permissions(mode)) : \
 111        S_ISLNK(mode) ? S_IFLNK : S_IFDIR)
 112
 113#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
 114
 115extern struct cache_entry **active_cache;
 116extern unsigned int active_nr, active_alloc, active_cache_changed;
 117
 118#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 119#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 120#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 121#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 122#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 123
 124extern char *get_git_dir(void);
 125extern char *get_object_directory(void);
 126extern char *get_refs_directory(void);
 127extern char *get_index_file(void);
 128extern char *get_graft_file(void);
 129
 130#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 131
 132extern const char **get_pathspec(const char *prefix, const char **pathspec);
 133extern const char *setup_git_directory_gently(int *);
 134extern const char *setup_git_directory(void);
 135extern const char *prefix_path(const char *prefix, int len, const char *path);
 136extern const char *prefix_filename(const char *prefix, int len, const char *path);
 137extern void verify_filename(const char *prefix, const char *name);
 138extern void verify_non_filename(const char *prefix, const char *name);
 139
 140#define alloc_nr(x) (((x)+16)*3/2)
 141
 142/* Initialize and use the cache information */
 143extern int read_cache(void);
 144extern int write_cache(int newfd, struct cache_entry **cache, int entries);
 145extern int cache_name_pos(const char *name, int namelen);
 146#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 147#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 148#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 149extern int add_cache_entry(struct cache_entry *ce, int option);
 150extern int remove_cache_entry_at(int pos);
 151extern int remove_file_from_cache(const char *path);
 152extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 153extern int ce_match_stat(struct cache_entry *ce, struct stat *st, int);
 154extern int ce_modified(struct cache_entry *ce, struct stat *st, int);
 155extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 156extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type);
 157extern int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object);
 158extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
 159extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 160
 161struct cache_file {
 162        struct cache_file *next;
 163        char lockfile[PATH_MAX];
 164};
 165extern int hold_index_file_for_update(struct cache_file *, const char *path);
 166extern int commit_index_file(struct cache_file *);
 167extern void rollback_index_file(struct cache_file *);
 168
 169/* Environment bits from configuration mechanism */
 170extern int trust_executable_bit;
 171extern int assume_unchanged;
 172extern int prefer_symlink_refs;
 173extern int warn_ambiguous_refs;
 174extern int diff_rename_limit_default;
 175extern int shared_repository;
 176extern const char *apply_default_whitespace;
 177
 178#define GIT_REPO_VERSION 0
 179extern int repository_format_version;
 180extern int check_repository_format(void);
 181
 182#define MTIME_CHANGED   0x0001
 183#define CTIME_CHANGED   0x0002
 184#define OWNER_CHANGED   0x0004
 185#define MODE_CHANGED    0x0008
 186#define INODE_CHANGED   0x0010
 187#define DATA_CHANGED    0x0020
 188#define TYPE_CHANGED    0x0040
 189
 190/* Return a statically allocated filename matching the sha1 signature */
 191extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 192extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 193extern char *sha1_file_name(const unsigned char *sha1);
 194extern char *sha1_pack_name(const unsigned char *sha1);
 195extern char *sha1_pack_index_name(const unsigned char *sha1);
 196extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 197extern const unsigned char null_sha1[20];
 198
 199int git_mkstemp(char *path, size_t n, const char *template);
 200
 201int adjust_shared_perm(const char *path);
 202int safe_create_leading_directories(char *path);
 203char *safe_strncpy(char *, const char *, size_t);
 204char *enter_repo(char *path, int strict);
 205
 206/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 207extern int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size);
 208extern int parse_sha1_header(char *hdr, char *type, unsigned long *sizep);
 209extern int sha1_object_info(const unsigned char *, char *, unsigned long *);
 210extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
 211extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
 212extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 213extern char *write_sha1_file_prepare(void *buf,
 214                                     unsigned long len,
 215                                     const char *type,
 216                                     unsigned char *sha1,
 217                                     unsigned char *hdr,
 218                                     int *hdrlen);
 219
 220extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 221
 222extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
 223                              size_t bufsize, size_t *bufposn);
 224extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
 225extern int move_temp_to_file(const char *tmpfile, char *filename);
 226
 227extern int has_sha1_pack(const unsigned char *sha1);
 228extern int has_sha1_file(const unsigned char *sha1);
 229
 230extern int has_pack_file(const unsigned char *sha1);
 231extern int has_pack_index(const unsigned char *sha1);
 232
 233/* Convert to/from hex/sha1 representation */
 234#define MINIMUM_ABBREV 4
 235#define DEFAULT_ABBREV 7
 236
 237extern int get_sha1(const char *str, unsigned char *sha1);
 238extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 239extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 240extern int read_ref(const char *filename, unsigned char *sha1);
 241extern const char *resolve_ref(const char *path, unsigned char *sha1, int);
 242extern int create_symref(const char *git_HEAD, const char *refs_heads_master);
 243extern int validate_symref(const char *git_HEAD);
 244
 245extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 246extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 247
 248extern void *read_object_with_reference(const unsigned char *sha1,
 249                                        const char *required_type,
 250                                        unsigned long *size,
 251                                        unsigned char *sha1_ret);
 252
 253const char *show_date(unsigned long time, int timezone);
 254int parse_date(const char *date, char *buf, int bufsize);
 255void datestamp(char *buf, int bufsize);
 256unsigned long approxidate(const char *);
 257
 258extern int setup_ident(void);
 259extern const char *git_author_info(int);
 260extern const char *git_committer_info(int);
 261
 262struct checkout {
 263        const char *base_dir;
 264        int base_dir_len;
 265        unsigned force:1,
 266                 quiet:1,
 267                 not_new:1,
 268                 refresh_cache:1;
 269};
 270
 271extern int checkout_entry(struct cache_entry *ce, struct checkout *state, char *topath);
 272
 273extern struct alternate_object_database {
 274        struct alternate_object_database *next;
 275        char *name;
 276        char base[FLEX_ARRAY]; /* more */
 277} *alt_odb_list;
 278extern void prepare_alt_odb(void);
 279
 280extern struct packed_git {
 281        struct packed_git *next;
 282        unsigned long index_size;
 283        unsigned long pack_size;
 284        unsigned int *index_base;
 285        void *pack_base;
 286        unsigned int pack_last_used;
 287        unsigned int pack_use_cnt;
 288        int pack_local;
 289        unsigned char sha1[20];
 290        /* something like ".git/objects/pack/xxxxx.pack" */
 291        char pack_name[FLEX_ARRAY]; /* more */
 292} *packed_git;
 293
 294struct pack_entry {
 295        unsigned int offset;
 296        unsigned char sha1[20];
 297        struct packed_git *p;
 298};
 299
 300struct ref {
 301        struct ref *next;
 302        unsigned char old_sha1[20];
 303        unsigned char new_sha1[20];
 304        unsigned char force;
 305        struct ref *peer_ref; /* when renaming */
 306        char name[FLEX_ARRAY]; /* more */
 307};
 308
 309extern int git_connect(int fd[2], char *url, const char *prog);
 310extern int finish_connect(pid_t pid);
 311extern int path_match(const char *path, int nr, char **match);
 312extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 313                      int nr_refspec, char **refspec, int all);
 314extern int get_ack(int fd, unsigned char *result_sha1);
 315extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match, int ignore_funny);
 316extern int server_supports(const char *feature);
 317
 318extern struct packed_git *parse_pack_index(unsigned char *sha1);
 319extern struct packed_git *parse_pack_index_file(const unsigned char *sha1,
 320                                                char *idx_path);
 321
 322extern void prepare_packed_git(void);
 323extern void install_packed_git(struct packed_git *pack);
 324
 325extern struct packed_git *find_sha1_pack(const unsigned char *sha1, 
 326                                         struct packed_git *packs);
 327
 328extern int use_packed_git(struct packed_git *);
 329extern void unuse_packed_git(struct packed_git *);
 330extern struct packed_git *add_packed_git(char *, int, int);
 331extern int num_packed_objects(const struct packed_git *p);
 332extern int nth_packed_object_sha1(const struct packed_git *, int, unsigned char*);
 333extern int find_pack_entry_one(const unsigned char *, struct pack_entry *, struct packed_git *);
 334extern void *unpack_entry_gently(struct pack_entry *, char *, unsigned long *);
 335extern void packed_object_info_detail(struct pack_entry *, char *, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
 336
 337/* Dumb servers support */
 338extern int update_server_info(int);
 339
 340typedef int (*config_fn_t)(const char *, const char *);
 341extern int git_default_config(const char *, const char *);
 342extern int git_config_from_file(config_fn_t fn, const char *);
 343extern int git_config(config_fn_t fn);
 344extern int git_config_int(const char *, const char *);
 345extern int git_config_bool(const char *, const char *);
 346extern int git_config_set(const char *, const char *);
 347extern int git_config_set_multivar(const char *, const char *, const char *, int);
 348extern int check_repository_format_version(const char *var, const char *value);
 349
 350#define MAX_GITNAME (1000)
 351extern char git_default_email[MAX_GITNAME];
 352extern char git_default_name[MAX_GITNAME];
 353
 354#define MAX_ENCODING_LENGTH 64
 355extern char git_commit_encoding[MAX_ENCODING_LENGTH];
 356
 357extern int copy_fd(int ifd, int ofd);
 358
 359/* Finish off pack transfer receiving end */
 360extern int receive_unpack_pack(int fd[2], const char *me, int quiet);
 361extern int receive_keep_pack(int fd[2], const char *me, int quiet);
 362
 363/* pager.c */
 364extern void setup_pager(void);
 365
 366/* base85 */
 367int decode_85(char *dst, char *line, int linelen);
 368void encode_85(char *buf, unsigned char *data, int bytes);
 369
 370#endif /* CACHE_H */