Andrew's git / gitweb.git / cache.h
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cache.hon commit Teach core object handling functions about gitlinks (f35a6d3)
   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" */
  69struct 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 */
  80struct 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 */
  93struct 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)
 119static 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}
 127static 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
 146extern struct cache_entry **active_cache;
 147extern unsigned int active_nr, active_alloc, active_cache_changed;
 148extern struct cache_tree *active_cache_tree;
 149
 150enum 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
 173extern int is_bare_repository_cfg;
 174extern int is_bare_repository(void);
 175extern int is_inside_git_dir(void);
 176extern const char *get_git_dir(void);
 177extern char *get_object_directory(void);
 178extern char *get_refs_directory(void);
 179extern char *get_index_file(void);
 180extern char *get_graft_file(void);
 181
 182#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 183
 184extern const char **get_pathspec(const char *prefix, const char **pathspec);
 185extern const char *setup_git_directory_gently(int *);
 186extern const char *setup_git_directory(void);
 187extern const char *prefix_path(const char *prefix, int len, const char *path);
 188extern const char *prefix_filename(const char *prefix, int len, const char *path);
 189extern void verify_filename(const char *prefix, const char *name);
 190extern void verify_non_filename(const char *prefix, const char *name);
 191
 192#define alloc_nr(x) (((x)+16)*3/2)
 193
 194/* Initialize and use the cache information */
 195extern int read_cache(void);
 196extern int read_cache_from(const char *path);
 197extern int write_cache(int newfd, struct cache_entry **cache, int entries);
 198extern int discard_cache(void);
 199extern int verify_path(const char *path);
 200extern int cache_name_pos(const char *name, int namelen);
 201#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 202#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 203#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 204extern int add_cache_entry(struct cache_entry *ce, int option);
 205extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
 206extern int remove_cache_entry_at(int pos);
 207extern int remove_file_from_cache(const char *path);
 208extern int add_file_to_cache(const char *path, int verbose);
 209extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 210extern int ce_match_stat(struct cache_entry *ce, struct stat *st, int);
 211extern int ce_modified(struct cache_entry *ce, struct stat *st, int);
 212extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 213extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, enum object_type type, const char *path);
 214extern int read_pipe(int fd, char** return_buf, unsigned long* return_size);
 215extern int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object);
 216extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
 217extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 218
 219#define REFRESH_REALLY          0x0001  /* ignore_valid */
 220#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 221#define REFRESH_QUIET           0x0004  /* be quiet about it */
 222#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 223extern int refresh_cache(unsigned int flags);
 224
 225struct lock_file {
 226        struct lock_file *next;
 227        char on_list;
 228        char filename[PATH_MAX];
 229};
 230extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 231extern int commit_lock_file(struct lock_file *);
 232
 233extern int hold_locked_index(struct lock_file *, int);
 234extern int commit_locked_index(struct lock_file *);
 235extern void set_alternate_index_output(const char *);
 236
 237extern void rollback_lock_file(struct lock_file *);
 238extern int delete_ref(const char *, unsigned char *sha1);
 239
 240/* Environment bits from configuration mechanism */
 241extern int use_legacy_headers;
 242extern int trust_executable_bit;
 243extern int has_symlinks;
 244extern int assume_unchanged;
 245extern int prefer_symlink_refs;
 246extern int log_all_ref_updates;
 247extern int warn_ambiguous_refs;
 248extern int shared_repository;
 249extern const char *apply_default_whitespace;
 250extern int zlib_compression_level;
 251extern size_t packed_git_window_size;
 252extern size_t packed_git_limit;
 253extern size_t delta_base_cache_limit;
 254extern int auto_crlf;
 255
 256#define GIT_REPO_VERSION 0
 257extern int repository_format_version;
 258extern int check_repository_format(void);
 259
 260#define MTIME_CHANGED   0x0001
 261#define CTIME_CHANGED   0x0002
 262#define OWNER_CHANGED   0x0004
 263#define MODE_CHANGED    0x0008
 264#define INODE_CHANGED   0x0010
 265#define DATA_CHANGED    0x0020
 266#define TYPE_CHANGED    0x0040
 267
 268/* Return a statically allocated filename matching the sha1 signature */
 269extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 270extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 271extern char *sha1_file_name(const unsigned char *sha1);
 272extern char *sha1_pack_name(const unsigned char *sha1);
 273extern char *sha1_pack_index_name(const unsigned char *sha1);
 274extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 275extern const unsigned char null_sha1[20];
 276static inline int is_null_sha1(const unsigned char *sha1)
 277{
 278        return !memcmp(sha1, null_sha1, 20);
 279}
 280static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 281{
 282        return memcmp(sha1, sha2, 20);
 283}
 284static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
 285{
 286        memcpy(sha_dst, sha_src, 20);
 287}
 288static inline void hashclr(unsigned char *hash)
 289{
 290        memset(hash, 0, 20);
 291}
 292
 293int git_mkstemp(char *path, size_t n, const char *template);
 294
 295enum sharedrepo {
 296        PERM_UMASK = 0,
 297        PERM_GROUP,
 298        PERM_EVERYBODY
 299};
 300int git_config_perm(const char *var, const char *value);
 301int adjust_shared_perm(const char *path);
 302int safe_create_leading_directories(char *path);
 303char *enter_repo(char *path, int strict);
 304
 305/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 306extern int sha1_object_info(const unsigned char *, unsigned long *);
 307extern void * read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size);
 308extern int hash_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1);
 309extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 310extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
 311
 312extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 313
 314extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
 315                              size_t bufsize, size_t *bufposn);
 316extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
 317extern int move_temp_to_file(const char *tmpfile, const char *filename);
 318
 319extern int has_sha1_pack(const unsigned char *sha1, const char **ignore);
 320extern int has_sha1_file(const unsigned char *sha1);
 321extern void *map_sha1_file(const unsigned char *sha1, unsigned long *);
 322extern int legacy_loose_object(unsigned char *);
 323
 324extern int has_pack_file(const unsigned char *sha1);
 325extern int has_pack_index(const unsigned char *sha1);
 326
 327extern signed char hexval_table[256];
 328static inline unsigned int hexval(unsigned int c)
 329{
 330        return hexval_table[c];
 331}
 332
 333/* Convert to/from hex/sha1 representation */
 334#define MINIMUM_ABBREV 4
 335#define DEFAULT_ABBREV 7
 336
 337extern int get_sha1(const char *str, unsigned char *sha1);
 338extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 339extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 340extern int read_ref(const char *filename, unsigned char *sha1);
 341extern const char *resolve_ref(const char *path, unsigned char *sha1, int, int *);
 342extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
 343extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
 344
 345extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
 346extern int validate_headref(const char *ref);
 347
 348extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 349extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 350
 351extern void *read_object_with_reference(const unsigned char *sha1,
 352                                        const char *required_type,
 353                                        unsigned long *size,
 354                                        unsigned char *sha1_ret);
 355
 356enum date_mode { DATE_NORMAL = 0, DATE_RELATIVE, DATE_SHORT };
 357const char *show_date(unsigned long time, int timezone, enum date_mode mode);
 358const char *show_rfc2822_date(unsigned long time, int timezone);
 359int parse_date(const char *date, char *buf, int bufsize);
 360void datestamp(char *buf, int bufsize);
 361unsigned long approxidate(const char *);
 362
 363extern const char *git_author_info(int);
 364extern const char *git_committer_info(int);
 365extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
 366
 367struct checkout {
 368        const char *base_dir;
 369        int base_dir_len;
 370        unsigned force:1,
 371                 quiet:1,
 372                 not_new:1,
 373                 refresh_cache:1;
 374};
 375
 376extern int checkout_entry(struct cache_entry *ce, struct checkout *state, char *topath);
 377
 378extern struct alternate_object_database {
 379        struct alternate_object_database *next;
 380        char *name;
 381        char base[FLEX_ARRAY]; /* more */
 382} *alt_odb_list;
 383extern void prepare_alt_odb(void);
 384
 385struct pack_window {
 386        struct pack_window *next;
 387        unsigned char *base;
 388        off_t offset;
 389        size_t len;
 390        unsigned int last_used;
 391        unsigned int inuse_cnt;
 392};
 393
 394extern struct packed_git {
 395        struct packed_git *next;
 396        struct pack_window *windows;
 397        const void *index_data;
 398        off_t index_size;
 399        off_t pack_size;
 400        time_t mtime;
 401        int index_version;
 402        int pack_fd;
 403        int pack_local;
 404        unsigned char sha1[20];
 405        /* something like ".git/objects/pack/xxxxx.pack" */
 406        char pack_name[FLEX_ARRAY]; /* more */
 407} *packed_git;
 408
 409struct pack_entry {
 410        off_t offset;
 411        unsigned char sha1[20];
 412        struct packed_git *p;
 413};
 414
 415struct ref {
 416        struct ref *next;
 417        unsigned char old_sha1[20];
 418        unsigned char new_sha1[20];
 419        unsigned char force;
 420        struct ref *peer_ref; /* when renaming */
 421        char name[FLEX_ARRAY]; /* more */
 422};
 423
 424#define REF_NORMAL      (1u << 0)
 425#define REF_HEADS       (1u << 1)
 426#define REF_TAGS        (1u << 2)
 427
 428extern pid_t git_connect(int fd[2], char *url, const char *prog);
 429extern int finish_connect(pid_t pid);
 430extern int path_match(const char *path, int nr, char **match);
 431extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 432                      int nr_refspec, char **refspec, int all);
 433extern int get_ack(int fd, unsigned char *result_sha1);
 434extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match, unsigned int flags);
 435extern int server_supports(const char *feature);
 436
 437extern struct packed_git *parse_pack_index(unsigned char *sha1);
 438extern struct packed_git *parse_pack_index_file(const unsigned char *sha1,
 439                                                const char *idx_path);
 440
 441extern void prepare_packed_git(void);
 442extern void reprepare_packed_git(void);
 443extern void install_packed_git(struct packed_git *pack);
 444
 445extern struct packed_git *find_sha1_pack(const unsigned char *sha1, 
 446                                         struct packed_git *packs);
 447
 448extern void pack_report(void);
 449extern unsigned char* use_pack(struct packed_git *, struct pack_window **, off_t, unsigned int *);
 450extern void unuse_pack(struct pack_window **);
 451extern struct packed_git *add_packed_git(const char *, int, int);
 452extern uint32_t num_packed_objects(const struct packed_git *p);
 453extern const unsigned char *nth_packed_object_sha1(const struct packed_git *, uint32_t);
 454extern off_t find_pack_entry_one(const unsigned char *, struct packed_git *);
 455extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
 456extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 457extern const char *packed_object_info_detail(struct packed_git *, off_t, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
 458
 459/* Dumb servers support */
 460extern int update_server_info(int);
 461
 462typedef int (*config_fn_t)(const char *, const char *);
 463extern int git_default_config(const char *, const char *);
 464extern int git_config_from_file(config_fn_t fn, const char *);
 465extern int git_config(config_fn_t fn);
 466extern int git_config_int(const char *, const char *);
 467extern int git_config_bool(const char *, const char *);
 468extern int git_config_set(const char *, const char *);
 469extern int git_config_set_multivar(const char *, const char *, const char *, int);
 470extern int git_config_rename_section(const char *, const char *);
 471extern int check_repository_format_version(const char *var, const char *value);
 472
 473#define MAX_GITNAME (1000)
 474extern char git_default_email[MAX_GITNAME];
 475extern char git_default_name[MAX_GITNAME];
 476
 477extern const char *git_commit_encoding;
 478extern const char *git_log_output_encoding;
 479
 480extern int copy_fd(int ifd, int ofd);
 481extern int read_in_full(int fd, void *buf, size_t count);
 482extern int write_in_full(int fd, const void *buf, size_t count);
 483extern void write_or_die(int fd, const void *buf, size_t count);
 484extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
 485extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
 486
 487/* pager.c */
 488extern void setup_pager(void);
 489extern int pager_in_use;
 490extern int pager_use_color;
 491
 492/* base85 */
 493int decode_85(char *dst, char *line, int linelen);
 494void encode_85(char *buf, unsigned char *data, int bytes);
 495
 496/* alloc.c */
 497struct blob;
 498struct tree;
 499struct commit;
 500struct tag;
 501extern struct blob *alloc_blob_node(void);
 502extern struct tree *alloc_tree_node(void);
 503extern struct commit *alloc_commit_node(void);
 504extern struct tag *alloc_tag_node(void);
 505extern void alloc_report(void);
 506
 507/* trace.c */
 508extern int nfasprintf(char **str, const char *fmt, ...);
 509extern int nfvasprintf(char **str, const char *fmt, va_list va);
 510extern void trace_printf(const char *format, ...);
 511extern void trace_argv_printf(const char **argv, int count, const char *format, ...);
 512
 513/* convert.c */
 514extern int convert_to_git(const char *path, char **bufp, unsigned long *sizep);
 515extern int convert_to_working_tree(const char *path, char **bufp, unsigned long *sizep);
 516
 517/* match-trees.c */
 518void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
 519
 520#endif /* CACHE_H */