cache.h

   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  * A "directory link" is a link to another git directory.
  29  *
  30  * The value 0160000 is not normally a valid mode, and
  31  * also just happens to be S_IFDIR + S_IFLNK
  32  *
  33  * NOTE! We *really* shouldn't depend on the S_IFxxx macros
  34  * always having the same values everywhere. We should use
  35  * our internal git values for these things, and then we can
  36  * translate that to the OS-specific value. It just so
  37  * happens that everybody shares the same bit representation
  38  * in the UNIX world (and apparently wider too..)
  39  */
  40 #define S_IFDIRLNK      0160000
  41 #define S_ISDIRLNK(m)   (((m) & S_IFMT) == S_IFDIRLNK)
  42
  43 /*
  44  * Intensive research over the course of many years has shown that
  45  * port 9418 is totally unused by anything else. Or
  46  *
  47  *      Your search - "port 9418" - did not match any documents.
  48  *
  49  * as www.google.com puts it.
  50  *
  51  * This port has been properly assigned for git use by IANA:
  52  * git (Assigned-9418) [I06-050728-0001].
  53  *
  54  *      git  9418/tcp   git pack transfer service
  55  *      git  9418/udp   git pack transfer service
  56  *
  57  * with Linus Torvalds <torvalds@osdl.org> as the point of
  58  * contact. September 2005.
  59  *
  60  * See http://www.iana.org/assignments/port-numbers
  61  */
  62 #define DEFAULT_GIT_PORT 9418
  63
  64 /*
  65  * Basic data structures for the directory cache
  66  */
  67
  68 #define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
  69 struct cache_header {
  70         unsigned int hdr_signature;
  71         unsigned int hdr_version;
  72         unsigned int hdr_entries;
  73 };
  74
  75 /*
  76  * The "cache_time" is just the low 32 bits of the
  77  * time. It doesn't matter if it overflows - we only
  78  * check it for equality in the 32 bits we save.
  79  */
  80 struct cache_time {
  81         unsigned int sec;
  82         unsigned int nsec;
  83 };
  84
  85 /*
  86  * dev/ino/uid/gid/size are also just tracked to the low 32 bits
  87  * Again - this is just a (very strong in practice) heuristic that
  88  * the inode hasn't changed.
  89  *
  90  * We save the fields in big-endian order to allow using the
  91  * index file over NFS transparently.
  92  */
  93 struct cache_entry {
  94         struct cache_time ce_ctime;
  95         struct cache_time ce_mtime;
  96         unsigned int ce_dev;
  97         unsigned int ce_ino;
  98         unsigned int ce_mode;
  99         unsigned int ce_uid;
 100         unsigned int ce_gid;
 101         unsigned int ce_size;
 102         unsigned char sha1[20];
 103         unsigned short ce_flags;
 104         char name[FLEX_ARRAY]; /* more */
 105 };
 106
 107 #define CE_NAMEMASK  (0x0fff)
 108 #define CE_STAGEMASK (0x3000)
 109 #define CE_UPDATE    (0x4000)
 110 #define CE_VALID     (0x8000)
 111 #define CE_STAGESHIFT 12
 112
 113 #define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
 114 #define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
 115 #define ce_size(ce) cache_entry_size(ce_namelen(ce))
 116 #define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
 117
 118 #define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 119 static inline unsigned int create_ce_mode(unsigned int mode)
 120 {
 121         if (S_ISLNK(mode))
 122                 return htonl(S_IFLNK);
 123         if (S_ISDIR(mode) || S_ISDIRLNK(mode))
 124                 return htonl(S_IFDIRLNK);
 125         return htonl(S_IFREG | ce_permissions(mode));
 126 }
 127 static inline unsigned int ce_mode_from_stat(struct cache_entry *ce, unsigned int mode)
 128 {
 129         extern int trust_executable_bit, has_symlinks;
 130         if (!has_symlinks && S_ISREG(mode) &&
 131             ce && S_ISLNK(ntohl(ce->ce_mode)))
 132                 return ce->ce_mode;
 133         if (!trust_executable_bit && S_ISREG(mode)) {
 134                 if (ce && S_ISREG(ntohl(ce->ce_mode)))
 135                         return ce->ce_mode;
 136                 return create_ce_mode(0666);
 137         }
 138         return create_ce_mode(mode);
 139 }
 140 #define canon_mode(mode) \
 141         (S_ISREG(mode) ? (S_IFREG | ce_permissions(mode)) : \
 142         S_ISLNK(mode) ? S_IFLNK : S_ISDIR(mode) ? S_IFDIR : S_IFDIRLNK)
 143
 144 #define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
 145
 146 extern struct cache_entry **active_cache;
 147 extern unsigned int active_nr, active_alloc, active_cache_changed;
 148 extern struct cache_tree *active_cache_tree;
 149
 150 enum object_type {
 151         OBJ_BAD = -1,
 152         OBJ_NONE = 0,
 153         OBJ_COMMIT = 1,
 154         OBJ_TREE = 2,
 155         OBJ_BLOB = 3,
 156         OBJ_TAG = 4,
 157         /* 5 for future expansion */
 158         OBJ_OFS_DELTA = 6,
 159         OBJ_REF_DELTA = 7,
 160         OBJ_MAX,
 161 };
 162
 163 #define GIT_DIR_ENVIRONMENT "GIT_DIR"
 164 #define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 165 #define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 166 #define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 167 #define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 168 #define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
 169 #define CONFIG_ENVIRONMENT "GIT_CONFIG"
 170 #define CONFIG_LOCAL_ENVIRONMENT "GIT_CONFIG_LOCAL"
 171 #define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 172 #define GITATTRIBUTES_FILE ".gitattributes"
 173 #define INFOATTRIBUTES_FILE "info/attributes"
 174 #define ATTRIBUTE_MACRO_PREFIX "[attr]"
 175
 176 extern int is_bare_repository_cfg;
 177 extern int is_bare_repository(void);
 178 extern int is_inside_git_dir(void);
 179 extern const char *get_git_dir(void);
 180 extern char *get_object_directory(void);
 181 extern char *get_refs_directory(void);
 182 extern char *get_index_file(void);
 183 extern char *get_graft_file(void);
 184
 185 #define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 186
 187 extern const char **get_pathspec(const char *prefix, const char **pathspec);
 188 extern const char *setup_git_directory_gently(int *);
 189 extern const char *setup_git_directory(void);
 190 extern const char *prefix_path(const char *prefix, int len, const char *path);
 191 extern const char *prefix_filename(const char *prefix, int len, const char *path);
 192 extern void verify_filename(const char *prefix, const char *name);
 193 extern void verify_non_filename(const char *prefix, const char *name);
 194
 195 #define alloc_nr(x) (((x)+16)*3/2)
 196
 197 /* Initialize and use the cache information */
 198 extern int read_cache(void);
 199 extern int read_cache_from(const char *path);
 200 extern int write_cache(int newfd, struct cache_entry **cache, int entries);
 201 extern int discard_cache(void);
 202 extern int verify_path(const char *path);
 203 extern int cache_name_pos(const char *name, int namelen);
 204 #define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 205 #define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 206 #define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 207 extern int add_cache_entry(struct cache_entry *ce, int option);
 208 extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
 209 extern int remove_cache_entry_at(int pos);
 210 extern int remove_file_from_cache(const char *path);
 211 extern int add_file_to_cache(const char *path, int verbose);
 212 extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 213 extern int ce_match_stat(struct cache_entry *ce, struct stat *st, int);
 214 extern int ce_modified(struct cache_entry *ce, struct stat *st, int);
 215 extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 216 extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, enum object_type type, const char *path);
 217 extern int read_pipe(int fd, char** return_buf, unsigned long* return_size);
 218 extern int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object);
 219 extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
 220 extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 221
 222 #define REFRESH_REALLY          0x0001  /* ignore_valid */
 223 #define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 224 #define REFRESH_QUIET           0x0004  /* be quiet about it */
 225 #define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 226 extern int refresh_cache(unsigned int flags);
 227
 228 struct lock_file {
 229         struct lock_file *next;
 230         pid_t owner;
 231         char on_list;
 232         char filename[PATH_MAX];
 233 };
 234 extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 235 extern int commit_lock_file(struct lock_file *);
 236
 237 extern int hold_locked_index(struct lock_file *, int);
 238 extern int commit_locked_index(struct lock_file *);
 239 extern void set_alternate_index_output(const char *);
 240
 241 extern void rollback_lock_file(struct lock_file *);
 242 extern int delete_ref(const char *, const unsigned char *sha1);
 243
 244 /* Environment bits from configuration mechanism */
 245 extern int use_legacy_headers;
 246 extern int trust_executable_bit;
 247 extern int has_symlinks;
 248 extern int assume_unchanged;
 249 extern int prefer_symlink_refs;
 250 extern int log_all_ref_updates;
 251 extern int warn_ambiguous_refs;
 252 extern int shared_repository;
 253 extern const char *apply_default_whitespace;
 254 extern int zlib_compression_level;
 255 extern size_t packed_git_window_size;
 256 extern size_t packed_git_limit;
 257 extern size_t delta_base_cache_limit;
 258 extern int auto_crlf;
 259
 260 #define GIT_REPO_VERSION 0
 261 extern int repository_format_version;
 262 extern int check_repository_format(void);
 263
 264 #define MTIME_CHANGED   0x0001
 265 #define CTIME_CHANGED   0x0002
 266 #define OWNER_CHANGED   0x0004
 267 #define MODE_CHANGED    0x0008
 268 #define INODE_CHANGED   0x0010
 269 #define DATA_CHANGED    0x0020
 270 #define TYPE_CHANGED    0x0040
 271
 272 /* Return a statically allocated filename matching the sha1 signature */
 273 extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 274 extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 275 extern char *sha1_file_name(const unsigned char *sha1);
 276 extern char *sha1_pack_name(const unsigned char *sha1);
 277 extern char *sha1_pack_index_name(const unsigned char *sha1);
 278 extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 279 extern const unsigned char null_sha1[20];
 280 static inline int is_null_sha1(const unsigned char *sha1)
 281 {
 282         return !memcmp(sha1, null_sha1, 20);
 283 }
 284 static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 285 {
 286         return memcmp(sha1, sha2, 20);
 287 }
 288 static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
 289 {
 290         memcpy(sha_dst, sha_src, 20);
 291 }
 292 static inline void hashclr(unsigned char *hash)
 293 {
 294         memset(hash, 0, 20);
 295 }
 296
 297 int git_mkstemp(char *path, size_t n, const char *template);
 298
 299 enum sharedrepo {
 300         PERM_UMASK = 0,
 301         PERM_GROUP,
 302         PERM_EVERYBODY
 303 };
 304 int git_config_perm(const char *var, const char *value);
 305 int adjust_shared_perm(const char *path);
 306 int safe_create_leading_directories(char *path);
 307 char *enter_repo(char *path, int strict);
 308
 309 /* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 310 extern int sha1_object_info(const unsigned char *, unsigned long *);
 311 extern void * read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size);
 312 extern int hash_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1);
 313 extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 314 extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
 315
 316 extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 317
 318 extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
 319                               size_t bufsize, size_t *bufposn);
 320 extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
 321 extern int move_temp_to_file(const char *tmpfile, const char *filename);
 322
 323 extern int has_sha1_pack(const unsigned char *sha1, const char **ignore);
 324 extern int has_sha1_file(const unsigned char *sha1);
 325 extern void *map_sha1_file(const unsigned char *sha1, unsigned long *);
 326 extern int legacy_loose_object(unsigned char *);
 327
 328 extern int has_pack_file(const unsigned char *sha1);
 329 extern int has_pack_index(const unsigned char *sha1);
 330
 331 extern signed char hexval_table[256];
 332 static inline unsigned int hexval(unsigned int c)
 333 {
 334         return hexval_table[c];
 335 }
 336
 337 /* Convert to/from hex/sha1 representation */
 338 #define MINIMUM_ABBREV 4
 339 #define DEFAULT_ABBREV 7
 340
 341 extern int get_sha1(const char *str, unsigned char *sha1);
 342 extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 343 extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 344 extern int read_ref(const char *filename, unsigned char *sha1);
 345 extern const char *resolve_ref(const char *path, unsigned char *sha1, int, int *);
 346 extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
 347 extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
 348
 349 extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
 350 extern int validate_headref(const char *ref);
 351
 352 extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 353 extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 354
 355 extern void *read_object_with_reference(const unsigned char *sha1,
 356                                         const char *required_type,
 357                                         unsigned long *size,
 358                                         unsigned char *sha1_ret);
 359
 360 enum date_mode { DATE_NORMAL = 0, DATE_RELATIVE, DATE_SHORT };
 361 const char *show_date(unsigned long time, int timezone, enum date_mode mode);
 362 const char *show_rfc2822_date(unsigned long time, int timezone);
 363 int parse_date(const char *date, char *buf, int bufsize);
 364 void datestamp(char *buf, int bufsize);
 365 unsigned long approxidate(const char *);
 366
 367 extern const char *git_author_info(int);
 368 extern const char *git_committer_info(int);
 369 extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
 370
 371 struct checkout {
 372         const char *base_dir;
 373         int base_dir_len;
 374         unsigned force:1,
 375                  quiet:1,
 376                  not_new:1,
 377                  refresh_cache:1;
 378 };
 379
 380 extern int checkout_entry(struct cache_entry *ce, struct checkout *state, char *topath);
 381
 382 extern struct alternate_object_database {
 383         struct alternate_object_database *next;
 384         char *name;
 385         char base[FLEX_ARRAY]; /* more */
 386 } *alt_odb_list;
 387 extern void prepare_alt_odb(void);
 388
 389 struct pack_window {
 390         struct pack_window *next;
 391         unsigned char *base;
 392         off_t offset;
 393         size_t len;
 394         unsigned int last_used;
 395         unsigned int inuse_cnt;
 396 };
 397
 398 extern struct packed_git {
 399         struct packed_git *next;
 400         struct pack_window *windows;
 401         off_t pack_size;
 402         const void *index_data;
 403         size_t index_size;
 404         uint32_t num_objects;
 405         int index_version;
 406         time_t mtime;
 407         int pack_fd;
 408         int pack_local;
 409         unsigned char sha1[20];
 410         /* something like ".git/objects/pack/xxxxx.pack" */
 411         char pack_name[FLEX_ARRAY]; /* more */
 412 } *packed_git;
 413
 414 struct pack_entry {
 415         off_t offset;
 416         unsigned char sha1[20];
 417         struct packed_git *p;
 418 };
 419
 420 struct ref {
 421         struct ref *next;
 422         unsigned char old_sha1[20];
 423         unsigned char new_sha1[20];
 424         unsigned char force;
 425         struct ref *peer_ref; /* when renaming */
 426         char name[FLEX_ARRAY]; /* more */
 427 };
 428
 429 #define REF_NORMAL      (1u << 0)
 430 #define REF_HEADS       (1u << 1)
 431 #define REF_TAGS        (1u << 2)
 432
 433 extern pid_t git_connect(int fd[2], char *url, const char *prog);
 434 extern int finish_connect(pid_t pid);
 435 extern int path_match(const char *path, int nr, char **match);
 436 extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 437                       int nr_refspec, char **refspec, int all);
 438 extern int get_ack(int fd, unsigned char *result_sha1);
 439 extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match, unsigned int flags);
 440 extern int server_supports(const char *feature);
 441
 442 extern struct packed_git *parse_pack_index(unsigned char *sha1);
 443 extern struct packed_git *parse_pack_index_file(const unsigned char *sha1,
 444                                                 const char *idx_path);
 445
 446 extern void prepare_packed_git(void);
 447 extern void reprepare_packed_git(void);
 448 extern void install_packed_git(struct packed_git *pack);
 449
 450 extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
 451                                          struct packed_git *packs);
 452
 453 extern void pack_report(void);
 454 extern unsigned char* use_pack(struct packed_git *, struct pack_window **, off_t, unsigned int *);
 455 extern void unuse_pack(struct pack_window **);
 456 extern struct packed_git *add_packed_git(const char *, int, int);
 457 extern const unsigned char *nth_packed_object_sha1(const struct packed_git *, uint32_t);
 458 extern off_t find_pack_entry_one(const unsigned char *, struct packed_git *);
 459 extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
 460 extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 461 extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
 462 extern const char *packed_object_info_detail(struct packed_git *, off_t, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
 463
 464 /* Dumb servers support */
 465 extern int update_server_info(int);
 466
 467 typedef int (*config_fn_t)(const char *, const char *);
 468 extern int git_default_config(const char *, const char *);
 469 extern int git_config_from_file(config_fn_t fn, const char *);
 470 extern int git_config(config_fn_t fn);
 471 extern int git_config_int(const char *, const char *);
 472 extern int git_config_bool(const char *, const char *);
 473 extern int git_config_set(const char *, const char *);
 474 extern int git_config_set_multivar(const char *, const char *, const char *, int);
 475 extern int git_config_rename_section(const char *, const char *);
 476 extern int check_repository_format_version(const char *var, const char *value);
 477
 478 #define MAX_GITNAME (1000)
 479 extern char git_default_email[MAX_GITNAME];
 480 extern char git_default_name[MAX_GITNAME];
 481
 482 extern const char *git_commit_encoding;
 483 extern const char *git_log_output_encoding;
 484
 485 extern int copy_fd(int ifd, int ofd);
 486 extern int read_in_full(int fd, void *buf, size_t count);
 487 extern int write_in_full(int fd, const void *buf, size_t count);
 488 extern void write_or_die(int fd, const void *buf, size_t count);
 489 extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
 490 extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
 491
 492 /* pager.c */
 493 extern void setup_pager(void);
 494 extern int pager_in_use;
 495 extern int pager_use_color;
 496
 497 /* base85 */
 498 int decode_85(char *dst, const char *line, int linelen);
 499 void encode_85(char *buf, const unsigned char *data, int bytes);
 500
 501 /* alloc.c */
 502 extern void *alloc_blob_node(void);
 503 extern void *alloc_tree_node(void);
 504 extern void *alloc_commit_node(void);
 505 extern void *alloc_tag_node(void);
 506 extern void *alloc_object_node(void);
 507 extern void alloc_report(void);
 508
 509 /* trace.c */
 510 extern int nfasprintf(char **str, const char *fmt, ...);
 511 extern int nfvasprintf(char **str, const char *fmt, va_list va);
 512 extern void trace_printf(const char *format, ...);
 513 extern void trace_argv_printf(const char **argv, int count, const char *format, ...);
 514
 515 /* convert.c */
 516 extern char *convert_to_git(const char *path, const char *src, unsigned long *sizep);
 517 extern char *convert_to_working_tree(const char *path, const char *src, unsigned long *sizep);
 518
 519 /* match-trees.c */
 520 void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
 521
 522 #endif /* CACHE_H */