cache.hon commit Git 2.0.3 (740c281)
   1#ifndef CACHE_H
   2#define CACHE_H
   3
   4#include "git-compat-util.h"
   5#include "strbuf.h"
   6#include "hashmap.h"
   7#include "advice.h"
   8#include "gettext.h"
   9#include "convert.h"
  10
  11#include SHA1_HEADER
  12#ifndef git_SHA_CTX
  13#define git_SHA_CTX     SHA_CTX
  14#define git_SHA1_Init   SHA1_Init
  15#define git_SHA1_Update SHA1_Update
  16#define git_SHA1_Final  SHA1_Final
  17#endif
  18
  19#include <zlib.h>
  20typedef struct git_zstream {
  21        z_stream z;
  22        unsigned long avail_in;
  23        unsigned long avail_out;
  24        unsigned long total_in;
  25        unsigned long total_out;
  26        unsigned char *next_in;
  27        unsigned char *next_out;
  28} git_zstream;
  29
  30void git_inflate_init(git_zstream *);
  31void git_inflate_init_gzip_only(git_zstream *);
  32void git_inflate_end(git_zstream *);
  33int git_inflate(git_zstream *, int flush);
  34
  35void git_deflate_init(git_zstream *, int level);
  36void git_deflate_init_gzip(git_zstream *, int level);
  37void git_deflate_init_raw(git_zstream *, int level);
  38void git_deflate_end(git_zstream *);
  39int git_deflate_abort(git_zstream *);
  40int git_deflate_end_gently(git_zstream *);
  41int git_deflate(git_zstream *, int flush);
  42unsigned long git_deflate_bound(git_zstream *, unsigned long);
  43
  44#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
  45#define DTYPE(de)       ((de)->d_type)
  46#else
  47#undef DT_UNKNOWN
  48#undef DT_DIR
  49#undef DT_REG
  50#undef DT_LNK
  51#define DT_UNKNOWN      0
  52#define DT_DIR          1
  53#define DT_REG          2
  54#define DT_LNK          3
  55#define DTYPE(de)       DT_UNKNOWN
  56#endif
  57
  58/* unknown mode (impossible combination S_IFIFO|S_IFCHR) */
  59#define S_IFINVALID     0030000
  60
  61/*
  62 * A "directory link" is a link to another git directory.
  63 *
  64 * The value 0160000 is not normally a valid mode, and
  65 * also just happens to be S_IFDIR + S_IFLNK
  66 *
  67 * NOTE! We *really* shouldn't depend on the S_IFxxx macros
  68 * always having the same values everywhere. We should use
  69 * our internal git values for these things, and then we can
  70 * translate that to the OS-specific value. It just so
  71 * happens that everybody shares the same bit representation
  72 * in the UNIX world (and apparently wider too..)
  73 */
  74#define S_IFGITLINK     0160000
  75#define S_ISGITLINK(m)  (((m) & S_IFMT) == S_IFGITLINK)
  76
  77/*
  78 * Intensive research over the course of many years has shown that
  79 * port 9418 is totally unused by anything else. Or
  80 *
  81 *      Your search - "port 9418" - did not match any documents.
  82 *
  83 * as www.google.com puts it.
  84 *
  85 * This port has been properly assigned for git use by IANA:
  86 * git (Assigned-9418) [I06-050728-0001].
  87 *
  88 *      git  9418/tcp   git pack transfer service
  89 *      git  9418/udp   git pack transfer service
  90 *
  91 * with Linus Torvalds <torvalds@osdl.org> as the point of
  92 * contact. September 2005.
  93 *
  94 * See http://www.iana.org/assignments/port-numbers
  95 */
  96#define DEFAULT_GIT_PORT 9418
  97
  98/*
  99 * Basic data structures for the directory cache
 100 */
 101
 102#define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
 103struct cache_header {
 104        uint32_t hdr_signature;
 105        uint32_t hdr_version;
 106        uint32_t hdr_entries;
 107};
 108
 109#define INDEX_FORMAT_LB 2
 110#define INDEX_FORMAT_UB 4
 111
 112/*
 113 * The "cache_time" is just the low 32 bits of the
 114 * time. It doesn't matter if it overflows - we only
 115 * check it for equality in the 32 bits we save.
 116 */
 117struct cache_time {
 118        uint32_t sec;
 119        uint32_t nsec;
 120};
 121
 122struct stat_data {
 123        struct cache_time sd_ctime;
 124        struct cache_time sd_mtime;
 125        unsigned int sd_dev;
 126        unsigned int sd_ino;
 127        unsigned int sd_uid;
 128        unsigned int sd_gid;
 129        unsigned int sd_size;
 130};
 131
 132struct cache_entry {
 133        struct hashmap_entry ent;
 134        struct stat_data ce_stat_data;
 135        unsigned int ce_mode;
 136        unsigned int ce_flags;
 137        unsigned int ce_namelen;
 138        unsigned char sha1[20];
 139        char name[FLEX_ARRAY]; /* more */
 140};
 141
 142#define CE_STAGEMASK (0x3000)
 143#define CE_EXTENDED  (0x4000)
 144#define CE_VALID     (0x8000)
 145#define CE_STAGESHIFT 12
 146
 147/*
 148 * Range 0xFFFF0000 in ce_flags is divided into
 149 * two parts: in-memory flags and on-disk ones.
 150 * Flags in CE_EXTENDED_FLAGS will get saved on-disk
 151 * if you want to save a new flag, add it in
 152 * CE_EXTENDED_FLAGS
 153 *
 154 * In-memory only flags
 155 */
 156#define CE_UPDATE            (1 << 16)
 157#define CE_REMOVE            (1 << 17)
 158#define CE_UPTODATE          (1 << 18)
 159#define CE_ADDED             (1 << 19)
 160
 161#define CE_HASHED            (1 << 20)
 162#define CE_WT_REMOVE         (1 << 22) /* remove in work directory */
 163#define CE_CONFLICTED        (1 << 23)
 164
 165#define CE_UNPACKED          (1 << 24)
 166#define CE_NEW_SKIP_WORKTREE (1 << 25)
 167
 168/* used to temporarily mark paths matched by pathspecs */
 169#define CE_MATCHED           (1 << 26)
 170
 171/*
 172 * Extended on-disk flags
 173 */
 174#define CE_INTENT_TO_ADD     (1 << 29)
 175#define CE_SKIP_WORKTREE     (1 << 30)
 176/* CE_EXTENDED2 is for future extension */
 177#define CE_EXTENDED2         (1 << 31)
 178
 179#define CE_EXTENDED_FLAGS (CE_INTENT_TO_ADD | CE_SKIP_WORKTREE)
 180
 181/*
 182 * Safeguard to avoid saving wrong flags:
 183 *  - CE_EXTENDED2 won't get saved until its semantic is known
 184 *  - Bits in 0x0000FFFF have been saved in ce_flags already
 185 *  - Bits in 0x003F0000 are currently in-memory flags
 186 */
 187#if CE_EXTENDED_FLAGS & 0x803FFFFF
 188#error "CE_EXTENDED_FLAGS out of range"
 189#endif
 190
 191struct pathspec;
 192
 193/*
 194 * Copy the sha1 and stat state of a cache entry from one to
 195 * another. But we never change the name, or the hash state!
 196 */
 197static inline void copy_cache_entry(struct cache_entry *dst,
 198                                    const struct cache_entry *src)
 199{
 200        unsigned int state = dst->ce_flags & CE_HASHED;
 201
 202        /* Don't copy hash chain and name */
 203        memcpy(&dst->ce_stat_data, &src->ce_stat_data,
 204                        offsetof(struct cache_entry, name) -
 205                        offsetof(struct cache_entry, ce_stat_data));
 206
 207        /* Restore the hash state */
 208        dst->ce_flags = (dst->ce_flags & ~CE_HASHED) | state;
 209}
 210
 211static inline unsigned create_ce_flags(unsigned stage)
 212{
 213        return (stage << CE_STAGESHIFT);
 214}
 215
 216#define ce_namelen(ce) ((ce)->ce_namelen)
 217#define ce_size(ce) cache_entry_size(ce_namelen(ce))
 218#define ce_stage(ce) ((CE_STAGEMASK & (ce)->ce_flags) >> CE_STAGESHIFT)
 219#define ce_uptodate(ce) ((ce)->ce_flags & CE_UPTODATE)
 220#define ce_skip_worktree(ce) ((ce)->ce_flags & CE_SKIP_WORKTREE)
 221#define ce_mark_uptodate(ce) ((ce)->ce_flags |= CE_UPTODATE)
 222
 223#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 224static inline unsigned int create_ce_mode(unsigned int mode)
 225{
 226        if (S_ISLNK(mode))
 227                return S_IFLNK;
 228        if (S_ISDIR(mode) || S_ISGITLINK(mode))
 229                return S_IFGITLINK;
 230        return S_IFREG | ce_permissions(mode);
 231}
 232static inline unsigned int ce_mode_from_stat(const struct cache_entry *ce,
 233                                             unsigned int mode)
 234{
 235        extern int trust_executable_bit, has_symlinks;
 236        if (!has_symlinks && S_ISREG(mode) &&
 237            ce && S_ISLNK(ce->ce_mode))
 238                return ce->ce_mode;
 239        if (!trust_executable_bit && S_ISREG(mode)) {
 240                if (ce && S_ISREG(ce->ce_mode))
 241                        return ce->ce_mode;
 242                return create_ce_mode(0666);
 243        }
 244        return create_ce_mode(mode);
 245}
 246static inline int ce_to_dtype(const struct cache_entry *ce)
 247{
 248        unsigned ce_mode = ntohl(ce->ce_mode);
 249        if (S_ISREG(ce_mode))
 250                return DT_REG;
 251        else if (S_ISDIR(ce_mode) || S_ISGITLINK(ce_mode))
 252                return DT_DIR;
 253        else if (S_ISLNK(ce_mode))
 254                return DT_LNK;
 255        else
 256                return DT_UNKNOWN;
 257}
 258static inline unsigned int canon_mode(unsigned int mode)
 259{
 260        if (S_ISREG(mode))
 261                return S_IFREG | ce_permissions(mode);
 262        if (S_ISLNK(mode))
 263                return S_IFLNK;
 264        if (S_ISDIR(mode))
 265                return S_IFDIR;
 266        return S_IFGITLINK;
 267}
 268
 269#define cache_entry_size(len) (offsetof(struct cache_entry,name) + (len) + 1)
 270
 271struct index_state {
 272        struct cache_entry **cache;
 273        unsigned int version;
 274        unsigned int cache_nr, cache_alloc, cache_changed;
 275        struct string_list *resolve_undo;
 276        struct cache_tree *cache_tree;
 277        struct cache_time timestamp;
 278        unsigned name_hash_initialized : 1,
 279                 initialized : 1;
 280        struct hashmap name_hash;
 281        struct hashmap dir_hash;
 282        unsigned char sha1[20];
 283};
 284
 285extern struct index_state the_index;
 286
 287/* Name hashing */
 288extern void add_name_hash(struct index_state *istate, struct cache_entry *ce);
 289extern void remove_name_hash(struct index_state *istate, struct cache_entry *ce);
 290extern void free_name_hash(struct index_state *istate);
 291
 292
 293#ifndef NO_THE_INDEX_COMPATIBILITY_MACROS
 294#define active_cache (the_index.cache)
 295#define active_nr (the_index.cache_nr)
 296#define active_alloc (the_index.cache_alloc)
 297#define active_cache_changed (the_index.cache_changed)
 298#define active_cache_tree (the_index.cache_tree)
 299
 300#define read_cache() read_index(&the_index)
 301#define read_cache_from(path) read_index_from(&the_index, (path))
 302#define read_cache_preload(pathspec) read_index_preload(&the_index, (pathspec))
 303#define is_cache_unborn() is_index_unborn(&the_index)
 304#define read_cache_unmerged() read_index_unmerged(&the_index)
 305#define write_cache(newfd, cache, entries) write_index(&the_index, (newfd))
 306#define discard_cache() discard_index(&the_index)
 307#define unmerged_cache() unmerged_index(&the_index)
 308#define cache_name_pos(name, namelen) index_name_pos(&the_index,(name),(namelen))
 309#define add_cache_entry(ce, option) add_index_entry(&the_index, (ce), (option))
 310#define rename_cache_entry_at(pos, new_name) rename_index_entry_at(&the_index, (pos), (new_name))
 311#define remove_cache_entry_at(pos) remove_index_entry_at(&the_index, (pos))
 312#define remove_file_from_cache(path) remove_file_from_index(&the_index, (path))
 313#define add_to_cache(path, st, flags) add_to_index(&the_index, (path), (st), (flags))
 314#define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags))
 315#define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
 316#define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
 317#define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
 318#define cache_dir_exists(name, namelen) index_dir_exists(&the_index, (name), (namelen))
 319#define cache_file_exists(name, namelen, igncase) index_file_exists(&the_index, (name), (namelen), (igncase))
 320#define cache_name_is_other(name, namelen) index_name_is_other(&the_index, (name), (namelen))
 321#define resolve_undo_clear() resolve_undo_clear_index(&the_index)
 322#define unmerge_cache_entry_at(at) unmerge_index_entry_at(&the_index, at)
 323#define unmerge_cache(pathspec) unmerge_index(&the_index, pathspec)
 324#define read_blob_data_from_cache(path, sz) read_blob_data_from_index(&the_index, (path), (sz))
 325#endif
 326
 327enum object_type {
 328        OBJ_BAD = -1,
 329        OBJ_NONE = 0,
 330        OBJ_COMMIT = 1,
 331        OBJ_TREE = 2,
 332        OBJ_BLOB = 3,
 333        OBJ_TAG = 4,
 334        /* 5 for future expansion */
 335        OBJ_OFS_DELTA = 6,
 336        OBJ_REF_DELTA = 7,
 337        OBJ_ANY,
 338        OBJ_MAX
 339};
 340
 341static inline enum object_type object_type(unsigned int mode)
 342{
 343        return S_ISDIR(mode) ? OBJ_TREE :
 344                S_ISGITLINK(mode) ? OBJ_COMMIT :
 345                OBJ_BLOB;
 346}
 347
 348/* Double-check local_repo_env below if you add to this list. */
 349#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 350#define GIT_NAMESPACE_ENVIRONMENT "GIT_NAMESPACE"
 351#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
 352#define GIT_PREFIX_ENVIRONMENT "GIT_PREFIX"
 353#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 354#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 355#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 356#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 357#define GIT_SHALLOW_FILE_ENVIRONMENT "GIT_SHALLOW_FILE"
 358#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
 359#define CONFIG_ENVIRONMENT "GIT_CONFIG"
 360#define CONFIG_DATA_ENVIRONMENT "GIT_CONFIG_PARAMETERS"
 361#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 362#define CEILING_DIRECTORIES_ENVIRONMENT "GIT_CEILING_DIRECTORIES"
 363#define NO_REPLACE_OBJECTS_ENVIRONMENT "GIT_NO_REPLACE_OBJECTS"
 364#define GITATTRIBUTES_FILE ".gitattributes"
 365#define INFOATTRIBUTES_FILE "info/attributes"
 366#define ATTRIBUTE_MACRO_PREFIX "[attr]"
 367#define GIT_NOTES_REF_ENVIRONMENT "GIT_NOTES_REF"
 368#define GIT_NOTES_DEFAULT_REF "refs/notes/commits"
 369#define GIT_NOTES_DISPLAY_REF_ENVIRONMENT "GIT_NOTES_DISPLAY_REF"
 370#define GIT_NOTES_REWRITE_REF_ENVIRONMENT "GIT_NOTES_REWRITE_REF"
 371#define GIT_NOTES_REWRITE_MODE_ENVIRONMENT "GIT_NOTES_REWRITE_MODE"
 372#define GIT_LITERAL_PATHSPECS_ENVIRONMENT "GIT_LITERAL_PATHSPECS"
 373#define GIT_GLOB_PATHSPECS_ENVIRONMENT "GIT_GLOB_PATHSPECS"
 374#define GIT_NOGLOB_PATHSPECS_ENVIRONMENT "GIT_NOGLOB_PATHSPECS"
 375#define GIT_ICASE_PATHSPECS_ENVIRONMENT "GIT_ICASE_PATHSPECS"
 376
 377/*
 378 * This environment variable is expected to contain a boolean indicating
 379 * whether we should or should not treat:
 380 *
 381 *   GIT_DIR=foo.git git ...
 382 *
 383 * as if GIT_WORK_TREE=. was given. It's not expected that users will make use
 384 * of this, but we use it internally to communicate to sub-processes that we
 385 * are in a bare repo. If not set, defaults to true.
 386 */
 387#define GIT_IMPLICIT_WORK_TREE_ENVIRONMENT "GIT_IMPLICIT_WORK_TREE"
 388
 389/*
 390 * Repository-local GIT_* environment variables; these will be cleared
 391 * when git spawns a sub-process that runs inside another repository.
 392 * The array is NULL-terminated, which makes it easy to pass in the "env"
 393 * parameter of a run-command invocation, or to do a simple walk.
 394 */
 395extern const char * const local_repo_env[];
 396
 397extern int is_bare_repository_cfg;
 398extern int is_bare_repository(void);
 399extern int is_inside_git_dir(void);
 400extern char *git_work_tree_cfg;
 401extern int is_inside_work_tree(void);
 402extern const char *get_git_dir(void);
 403extern int is_git_directory(const char *path);
 404extern char *get_object_directory(void);
 405extern char *get_index_file(void);
 406extern char *get_graft_file(void);
 407extern int set_git_dir(const char *path);
 408extern const char *get_git_namespace(void);
 409extern const char *strip_namespace(const char *namespaced_ref);
 410extern const char *get_git_work_tree(void);
 411extern const char *read_gitfile(const char *path);
 412extern const char *resolve_gitdir(const char *suspect);
 413extern void set_git_work_tree(const char *tree);
 414
 415#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 416
 417extern const char **get_pathspec(const char *prefix, const char **pathspec);
 418extern void setup_work_tree(void);
 419extern const char *setup_git_directory_gently(int *);
 420extern const char *setup_git_directory(void);
 421extern char *prefix_path(const char *prefix, int len, const char *path);
 422extern char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
 423extern const char *prefix_filename(const char *prefix, int len, const char *path);
 424extern int check_filename(const char *prefix, const char *name);
 425extern void verify_filename(const char *prefix,
 426                            const char *name,
 427                            int diagnose_misspelt_rev);
 428extern void verify_non_filename(const char *prefix, const char *name);
 429extern int path_inside_repo(const char *prefix, const char *path);
 430
 431#define INIT_DB_QUIET 0x0001
 432
 433extern int set_git_dir_init(const char *git_dir, const char *real_git_dir, int);
 434extern int init_db(const char *template_dir, unsigned int flags);
 435
 436extern void sanitize_stdfds(void);
 437extern int daemonize(void);
 438
 439#define alloc_nr(x) (((x)+16)*3/2)
 440
 441/*
 442 * Realloc the buffer pointed at by variable 'x' so that it can hold
 443 * at least 'nr' entries; the number of entries currently allocated
 444 * is 'alloc', using the standard growing factor alloc_nr() macro.
 445 *
 446 * DO NOT USE any expression with side-effect for 'x', 'nr', or 'alloc'.
 447 */
 448#define ALLOC_GROW(x, nr, alloc) \
 449        do { \
 450                if ((nr) > alloc) { \
 451                        if (alloc_nr(alloc) < (nr)) \
 452                                alloc = (nr); \
 453                        else \
 454                                alloc = alloc_nr(alloc); \
 455                        x = xrealloc((x), alloc * sizeof(*(x))); \
 456                } \
 457        } while (0)
 458
 459/* Initialize and use the cache information */
 460extern int read_index(struct index_state *);
 461extern int read_index_preload(struct index_state *, const struct pathspec *pathspec);
 462extern int read_index_from(struct index_state *, const char *path);
 463extern int is_index_unborn(struct index_state *);
 464extern int read_index_unmerged(struct index_state *);
 465extern int write_index(struct index_state *, int newfd);
 466extern int discard_index(struct index_state *);
 467extern int unmerged_index(const struct index_state *);
 468extern int verify_path(const char *path);
 469extern struct cache_entry *index_dir_exists(struct index_state *istate, const char *name, int namelen);
 470extern struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 471extern int index_name_pos(const struct index_state *, const char *name, int namelen);
 472#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 473#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 474#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 475#define ADD_CACHE_JUST_APPEND 8         /* Append only; tree.c::read_tree() */
 476#define ADD_CACHE_NEW_ONLY 16           /* Do not replace existing ones */
 477extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
 478extern void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
 479extern int remove_index_entry_at(struct index_state *, int pos);
 480extern void remove_marked_cache_entries(struct index_state *istate);
 481extern int remove_file_from_index(struct index_state *, const char *path);
 482#define ADD_CACHE_VERBOSE 1
 483#define ADD_CACHE_PRETEND 2
 484#define ADD_CACHE_IGNORE_ERRORS 4
 485#define ADD_CACHE_IGNORE_REMOVAL 8
 486#define ADD_CACHE_INTENT 16
 487extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
 488extern int add_file_to_index(struct index_state *, const char *path, int flags);
 489extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, unsigned int refresh_options);
 490extern int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
 491extern void set_object_name_for_intent_to_add_entry(struct cache_entry *ce);
 492extern int index_name_is_other(const struct index_state *, const char *, int);
 493extern void *read_blob_data_from_index(struct index_state *, const char *, unsigned long *);
 494
 495/* do stat comparison even if CE_VALID is true */
 496#define CE_MATCH_IGNORE_VALID           01
 497/* do not check the contents but report dirty on racily-clean entries */
 498#define CE_MATCH_RACY_IS_DIRTY          02
 499/* do stat comparison even if CE_SKIP_WORKTREE is true */
 500#define CE_MATCH_IGNORE_SKIP_WORKTREE   04
 501/* ignore non-existent files during stat update  */
 502#define CE_MATCH_IGNORE_MISSING         0x08
 503/* enable stat refresh */
 504#define CE_MATCH_REFRESH                0x10
 505extern int ie_match_stat(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 506extern int ie_modified(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 507
 508#define HASH_WRITE_OBJECT 1
 509#define HASH_FORMAT_CHECK 2
 510extern int index_fd(unsigned char *sha1, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
 511extern int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags);
 512
 513/*
 514 * Record to sd the data from st that we use to check whether a file
 515 * might have changed.
 516 */
 517extern void fill_stat_data(struct stat_data *sd, struct stat *st);
 518
 519/*
 520 * Return 0 if st is consistent with a file not having been changed
 521 * since sd was filled.  If there are differences, return a
 522 * combination of MTIME_CHANGED, CTIME_CHANGED, OWNER_CHANGED,
 523 * INODE_CHANGED, and DATA_CHANGED.
 524 */
 525extern int match_stat_data(const struct stat_data *sd, struct stat *st);
 526
 527extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 528
 529#define REFRESH_REALLY          0x0001  /* ignore_valid */
 530#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 531#define REFRESH_QUIET           0x0004  /* be quiet about it */
 532#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 533#define REFRESH_IGNORE_SUBMODULES       0x0010  /* ignore submodules */
 534#define REFRESH_IN_PORCELAIN    0x0020  /* user friendly output, not "needs update" */
 535extern int refresh_index(struct index_state *, unsigned int flags, const struct pathspec *pathspec, char *seen, const char *header_msg);
 536
 537struct lock_file {
 538        struct lock_file *next;
 539        int fd;
 540        pid_t owner;
 541        char on_list;
 542        char filename[PATH_MAX];
 543};
 544#define LOCK_DIE_ON_ERROR 1
 545#define LOCK_NODEREF 2
 546extern int unable_to_lock_error(const char *path, int err);
 547extern NORETURN void unable_to_lock_index_die(const char *path, int err);
 548extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 549extern int hold_lock_file_for_append(struct lock_file *, const char *path, int);
 550extern int commit_lock_file(struct lock_file *);
 551extern void update_index_if_able(struct index_state *, struct lock_file *);
 552
 553extern int hold_locked_index(struct lock_file *, int);
 554extern int commit_locked_index(struct lock_file *);
 555extern void set_alternate_index_output(const char *);
 556extern int close_lock_file(struct lock_file *);
 557extern void rollback_lock_file(struct lock_file *);
 558extern int delete_ref(const char *, const unsigned char *sha1, int delopt);
 559
 560/* Environment bits from configuration mechanism */
 561extern int trust_executable_bit;
 562extern int trust_ctime;
 563extern int check_stat;
 564extern int quote_path_fully;
 565extern int has_symlinks;
 566extern int minimum_abbrev, default_abbrev;
 567extern int ignore_case;
 568extern int assume_unchanged;
 569extern int prefer_symlink_refs;
 570extern int log_all_ref_updates;
 571extern int warn_ambiguous_refs;
 572extern int warn_on_object_refname_ambiguity;
 573extern int shared_repository;
 574extern const char *apply_default_whitespace;
 575extern const char *apply_default_ignorewhitespace;
 576extern const char *git_attributes_file;
 577extern int zlib_compression_level;
 578extern int core_compression_level;
 579extern int core_compression_seen;
 580extern size_t packed_git_window_size;
 581extern size_t packed_git_limit;
 582extern size_t delta_base_cache_limit;
 583extern unsigned long big_file_threshold;
 584extern unsigned long pack_size_limit_cfg;
 585
 586/*
 587 * Do replace refs need to be checked this run?  This variable is
 588 * initialized to true unless --no-replace-object is used or
 589 * $GIT_NO_REPLACE_OBJECTS is set, but is set to false by some
 590 * commands that do not want replace references to be active.  As an
 591 * optimization it is also set to false if replace references have
 592 * been sought but there were none.
 593 */
 594extern int check_replace_refs;
 595
 596extern int fsync_object_files;
 597extern int core_preload_index;
 598extern int core_apply_sparse_checkout;
 599extern int precomposed_unicode;
 600
 601/*
 602 * The character that begins a commented line in user-editable file
 603 * that is subject to stripspace.
 604 */
 605extern char comment_line_char;
 606
 607enum branch_track {
 608        BRANCH_TRACK_UNSPECIFIED = -1,
 609        BRANCH_TRACK_NEVER = 0,
 610        BRANCH_TRACK_REMOTE,
 611        BRANCH_TRACK_ALWAYS,
 612        BRANCH_TRACK_EXPLICIT,
 613        BRANCH_TRACK_OVERRIDE
 614};
 615
 616enum rebase_setup_type {
 617        AUTOREBASE_NEVER = 0,
 618        AUTOREBASE_LOCAL,
 619        AUTOREBASE_REMOTE,
 620        AUTOREBASE_ALWAYS
 621};
 622
 623enum push_default_type {
 624        PUSH_DEFAULT_NOTHING = 0,
 625        PUSH_DEFAULT_MATCHING,
 626        PUSH_DEFAULT_SIMPLE,
 627        PUSH_DEFAULT_UPSTREAM,
 628        PUSH_DEFAULT_CURRENT,
 629        PUSH_DEFAULT_UNSPECIFIED
 630};
 631
 632extern enum branch_track git_branch_track;
 633extern enum rebase_setup_type autorebase;
 634extern enum push_default_type push_default;
 635
 636enum object_creation_mode {
 637        OBJECT_CREATION_USES_HARDLINKS = 0,
 638        OBJECT_CREATION_USES_RENAMES = 1
 639};
 640
 641extern enum object_creation_mode object_creation_mode;
 642
 643extern char *notes_ref_name;
 644
 645extern int grafts_replace_parents;
 646
 647#define GIT_REPO_VERSION 0
 648extern int repository_format_version;
 649extern int check_repository_format(void);
 650
 651#define MTIME_CHANGED   0x0001
 652#define CTIME_CHANGED   0x0002
 653#define OWNER_CHANGED   0x0004
 654#define MODE_CHANGED    0x0008
 655#define INODE_CHANGED   0x0010
 656#define DATA_CHANGED    0x0020
 657#define TYPE_CHANGED    0x0040
 658
 659extern char *mksnpath(char *buf, size_t n, const char *fmt, ...)
 660        __attribute__((format (printf, 3, 4)));
 661extern char *git_snpath(char *buf, size_t n, const char *fmt, ...)
 662        __attribute__((format (printf, 3, 4)));
 663extern char *git_pathdup(const char *fmt, ...)
 664        __attribute__((format (printf, 1, 2)));
 665extern char *mkpathdup(const char *fmt, ...)
 666        __attribute__((format (printf, 1, 2)));
 667
 668/* Return a statically allocated filename matching the sha1 signature */
 669extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 670extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 671extern char *git_path_submodule(const char *path, const char *fmt, ...)
 672        __attribute__((format (printf, 2, 3)));
 673
 674/*
 675 * Return the name of the file in the local object database that would
 676 * be used to store a loose object with the specified sha1.  The
 677 * return value is a pointer to a statically allocated buffer that is
 678 * overwritten each time the function is called.
 679 */
 680extern const char *sha1_file_name(const unsigned char *sha1);
 681
 682/*
 683 * Return the name of the (local) packfile with the specified sha1 in
 684 * its name.  The return value is a pointer to memory that is
 685 * overwritten each time this function is called.
 686 */
 687extern char *sha1_pack_name(const unsigned char *sha1);
 688
 689/*
 690 * Return the name of the (local) pack index file with the specified
 691 * sha1 in its name.  The return value is a pointer to memory that is
 692 * overwritten each time this function is called.
 693 */
 694extern char *sha1_pack_index_name(const unsigned char *sha1);
 695
 696extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 697extern const unsigned char null_sha1[20];
 698
 699static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 700{
 701        int i;
 702
 703        for (i = 0; i < 20; i++, sha1++, sha2++) {
 704                if (*sha1 != *sha2)
 705                        return *sha1 - *sha2;
 706        }
 707
 708        return 0;
 709}
 710
 711static inline int is_null_sha1(const unsigned char *sha1)
 712{
 713        return !hashcmp(sha1, null_sha1);
 714}
 715
 716static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
 717{
 718        memcpy(sha_dst, sha_src, 20);
 719}
 720static inline void hashclr(unsigned char *hash)
 721{
 722        memset(hash, 0, 20);
 723}
 724
 725#define EMPTY_TREE_SHA1_HEX \
 726        "4b825dc642cb6eb9a060e54bf8d69288fbee4904"
 727#define EMPTY_TREE_SHA1_BIN_LITERAL \
 728         "\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
 729         "\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
 730#define EMPTY_TREE_SHA1_BIN \
 731         ((const unsigned char *) EMPTY_TREE_SHA1_BIN_LITERAL)
 732
 733#define EMPTY_BLOB_SHA1_HEX \
 734        "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"
 735#define EMPTY_BLOB_SHA1_BIN_LITERAL \
 736        "\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
 737        "\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
 738#define EMPTY_BLOB_SHA1_BIN \
 739        ((const unsigned char *) EMPTY_BLOB_SHA1_BIN_LITERAL)
 740
 741static inline int is_empty_blob_sha1(const unsigned char *sha1)
 742{
 743        return !hashcmp(sha1, EMPTY_BLOB_SHA1_BIN);
 744}
 745
 746int git_mkstemp(char *path, size_t n, const char *template);
 747
 748int git_mkstemps(char *path, size_t n, const char *template, int suffix_len);
 749
 750/* set default permissions by passing mode arguments to open(2) */
 751int git_mkstemps_mode(char *pattern, int suffix_len, int mode);
 752int git_mkstemp_mode(char *pattern, int mode);
 753
 754/*
 755 * NOTE NOTE NOTE!!
 756 *
 757 * PERM_UMASK, OLD_PERM_GROUP and OLD_PERM_EVERYBODY enumerations must
 758 * not be changed. Old repositories have core.sharedrepository written in
 759 * numeric format, and therefore these values are preserved for compatibility
 760 * reasons.
 761 */
 762enum sharedrepo {
 763        PERM_UMASK          = 0,
 764        OLD_PERM_GROUP      = 1,
 765        OLD_PERM_EVERYBODY  = 2,
 766        PERM_GROUP          = 0660,
 767        PERM_EVERYBODY      = 0664
 768};
 769int git_config_perm(const char *var, const char *value);
 770int adjust_shared_perm(const char *path);
 771
 772/*
 773 * Create the directory containing the named path, using care to be
 774 * somewhat safe against races.  Return one of the scld_error values
 775 * to indicate success/failure.
 776 *
 777 * SCLD_VANISHED indicates that one of the ancestor directories of the
 778 * path existed at one point during the function call and then
 779 * suddenly vanished, probably because another process pruned the
 780 * directory while we were working.  To be robust against this kind of
 781 * race, callers might want to try invoking the function again when it
 782 * returns SCLD_VANISHED.
 783 */
 784enum scld_error {
 785        SCLD_OK = 0,
 786        SCLD_FAILED = -1,
 787        SCLD_PERMS = -2,
 788        SCLD_EXISTS = -3,
 789        SCLD_VANISHED = -4
 790};
 791enum scld_error safe_create_leading_directories(char *path);
 792enum scld_error safe_create_leading_directories_const(const char *path);
 793
 794int mkdir_in_gitdir(const char *path);
 795extern void home_config_paths(char **global, char **xdg, char *file);
 796extern char *expand_user_path(const char *path);
 797const char *enter_repo(const char *path, int strict);
 798static inline int is_absolute_path(const char *path)
 799{
 800        return is_dir_sep(path[0]) || has_dos_drive_prefix(path);
 801}
 802int is_directory(const char *);
 803const char *real_path(const char *path);
 804const char *real_path_if_valid(const char *path);
 805const char *absolute_path(const char *path);
 806const char *remove_leading_path(const char *in, const char *prefix);
 807const char *relative_path(const char *in, const char *prefix, struct strbuf *sb);
 808int normalize_path_copy_len(char *dst, const char *src, int *prefix_len);
 809int normalize_path_copy(char *dst, const char *src);
 810int longest_ancestor_length(const char *path, struct string_list *prefixes);
 811char *strip_path_suffix(const char *path, const char *suffix);
 812int daemon_avoid_alias(const char *path);
 813int offset_1st_component(const char *path);
 814
 815/* object replacement */
 816#define LOOKUP_REPLACE_OBJECT 1
 817extern void *read_sha1_file_extended(const unsigned char *sha1, enum object_type *type, unsigned long *size, unsigned flag);
 818static inline void *read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 819{
 820        return read_sha1_file_extended(sha1, type, size, LOOKUP_REPLACE_OBJECT);
 821}
 822
 823/*
 824 * This internal function is only declared here for the benefit of
 825 * lookup_replace_object().  Please do not call it directly.
 826 */
 827extern const unsigned char *do_lookup_replace_object(const unsigned char *sha1);
 828
 829/*
 830 * If object sha1 should be replaced, return the replacement object's
 831 * name (replaced recursively, if necessary).  The return value is
 832 * either sha1 or a pointer to a permanently-allocated value.  When
 833 * object replacement is suppressed, always return sha1.
 834 */
 835static inline const unsigned char *lookup_replace_object(const unsigned char *sha1)
 836{
 837        if (!check_replace_refs)
 838                return sha1;
 839        return do_lookup_replace_object(sha1);
 840}
 841
 842static inline const unsigned char *lookup_replace_object_extended(const unsigned char *sha1, unsigned flag)
 843{
 844        if (!(flag & LOOKUP_REPLACE_OBJECT))
 845                return sha1;
 846        return lookup_replace_object(sha1);
 847}
 848
 849/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 850extern int sha1_object_info(const unsigned char *, unsigned long *);
 851extern int hash_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1);
 852extern int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 853extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
 854extern int force_object_loose(const unsigned char *sha1, time_t mtime);
 855extern int git_open_noatime(const char *name);
 856extern void *map_sha1_file(const unsigned char *sha1, unsigned long *size);
 857extern int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz);
 858extern int parse_sha1_header(const char *hdr, unsigned long *sizep);
 859
 860/* global flag to enable extra checks when accessing packed objects */
 861extern int do_check_packed_object_crc;
 862
 863extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 864
 865extern int move_temp_to_file(const char *tmpfile, const char *filename);
 866
 867extern int has_sha1_pack(const unsigned char *sha1);
 868
 869/*
 870 * Return true iff we have an object named sha1, whether local or in
 871 * an alternate object database, and whether packed or loose.  This
 872 * function does not respect replace references.
 873 */
 874extern int has_sha1_file(const unsigned char *sha1);
 875
 876/*
 877 * Return true iff an alternate object database has a loose object
 878 * with the specified name.  This function does not respect replace
 879 * references.
 880 */
 881extern int has_loose_object_nonlocal(const unsigned char *sha1);
 882
 883extern int has_pack_index(const unsigned char *sha1);
 884
 885extern void assert_sha1_type(const unsigned char *sha1, enum object_type expect);
 886
 887extern const signed char hexval_table[256];
 888static inline unsigned int hexval(unsigned char c)
 889{
 890        return hexval_table[c];
 891}
 892
 893/* Convert to/from hex/sha1 representation */
 894#define MINIMUM_ABBREV minimum_abbrev
 895#define DEFAULT_ABBREV default_abbrev
 896
 897struct object_context {
 898        unsigned char tree[20];
 899        char path[PATH_MAX];
 900        unsigned mode;
 901};
 902
 903#define GET_SHA1_QUIETLY        01
 904#define GET_SHA1_COMMIT         02
 905#define GET_SHA1_COMMITTISH     04
 906#define GET_SHA1_TREE          010
 907#define GET_SHA1_TREEISH       020
 908#define GET_SHA1_BLOB          040
 909#define GET_SHA1_ONLY_TO_DIE 04000
 910
 911extern int get_sha1(const char *str, unsigned char *sha1);
 912extern int get_sha1_commit(const char *str, unsigned char *sha1);
 913extern int get_sha1_committish(const char *str, unsigned char *sha1);
 914extern int get_sha1_tree(const char *str, unsigned char *sha1);
 915extern int get_sha1_treeish(const char *str, unsigned char *sha1);
 916extern int get_sha1_blob(const char *str, unsigned char *sha1);
 917extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
 918extern int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc);
 919
 920typedef int each_abbrev_fn(const unsigned char *sha1, void *);
 921extern int for_each_abbrev(const char *prefix, each_abbrev_fn, void *);
 922
 923/*
 924 * Try to read a SHA1 in hexadecimal format from the 40 characters
 925 * starting at hex.  Write the 20-byte result to sha1 in binary form.
 926 * Return 0 on success.  Reading stops if a NUL is encountered in the
 927 * input, so it is safe to pass this function an arbitrary
 928 * null-terminated string.
 929 */
 930extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 931
 932extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 933extern int read_ref_full(const char *refname, unsigned char *sha1,
 934                         int reading, int *flags);
 935extern int read_ref(const char *refname, unsigned char *sha1);
 936
 937/*
 938 * Resolve a reference, recursively following symbolic refererences.
 939 *
 940 * Store the referred-to object's name in sha1 and return the name of
 941 * the non-symbolic reference that ultimately pointed at it.  The
 942 * return value, if not NULL, is a pointer into either a static buffer
 943 * or the input ref.
 944 *
 945 * If the reference cannot be resolved to an object, the behavior
 946 * depends on the "reading" argument:
 947 *
 948 * - If reading is set, return NULL.
 949 *
 950 * - If reading is not set, clear sha1 and return the name of the last
 951 *   reference name in the chain, which will either be a non-symbolic
 952 *   reference or an undefined reference.  If this is a prelude to
 953 *   "writing" to the ref, the return value is the name of the ref
 954 *   that will actually be created or changed.
 955 *
 956 * If flag is non-NULL, set the value that it points to the
 957 * combination of REF_ISPACKED (if the reference was found among the
 958 * packed references) and REF_ISSYMREF (if the initial reference was a
 959 * symbolic reference).
 960 *
 961 * If ref is not a properly-formatted, normalized reference, return
 962 * NULL.  If more than MAXDEPTH recursive symbolic lookups are needed,
 963 * give up and return NULL.
 964 *
 965 * errno is sometimes set on errors, but not always.
 966 */
 967extern const char *resolve_ref_unsafe(const char *ref, unsigned char *sha1, int reading, int *flag);
 968extern char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag);
 969
 970extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
 971extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
 972extern int interpret_branch_name(const char *str, int len, struct strbuf *);
 973extern int get_sha1_mb(const char *str, unsigned char *sha1);
 974
 975/*
 976 * Return true iff abbrev_name is a possible abbreviation for
 977 * full_name according to the rules defined by ref_rev_parse_rules in
 978 * refs.c.
 979 */
 980extern int refname_match(const char *abbrev_name, const char *full_name);
 981
 982extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
 983extern int validate_headref(const char *ref);
 984
 985extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 986extern int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 987extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 988extern int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2);
 989
 990extern void *read_object_with_reference(const unsigned char *sha1,
 991                                        const char *required_type,
 992                                        unsigned long *size,
 993                                        unsigned char *sha1_ret);
 994
 995extern struct object *peel_to_type(const char *name, int namelen,
 996                                   struct object *o, enum object_type);
 997
 998enum date_mode {
 999        DATE_NORMAL = 0,
1000        DATE_RELATIVE,
1001        DATE_SHORT,
1002        DATE_LOCAL,
1003        DATE_ISO8601,
1004        DATE_RFC2822,
1005        DATE_RAW
1006};
1007
1008const char *show_date(unsigned long time, int timezone, enum date_mode mode);
1009void show_date_relative(unsigned long time, int tz, const struct timeval *now,
1010                        struct strbuf *timebuf);
1011int parse_date(const char *date, char *buf, int bufsize);
1012int parse_date_basic(const char *date, unsigned long *timestamp, int *offset);
1013int parse_expiry_date(const char *date, unsigned long *timestamp);
1014void datestamp(char *buf, int bufsize);
1015#define approxidate(s) approxidate_careful((s), NULL)
1016unsigned long approxidate_careful(const char *, int *);
1017unsigned long approxidate_relative(const char *date, const struct timeval *now);
1018enum date_mode parse_date_format(const char *format);
1019int date_overflows(unsigned long date);
1020
1021#define IDENT_STRICT           1
1022#define IDENT_NO_DATE          2
1023#define IDENT_NO_NAME          4
1024extern const char *git_author_info(int);
1025extern const char *git_committer_info(int);
1026extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
1027extern const char *fmt_name(const char *name, const char *email);
1028extern const char *ident_default_email(void);
1029extern const char *git_editor(void);
1030extern const char *git_pager(int stdout_is_tty);
1031extern int git_ident_config(const char *, const char *, void *);
1032
1033struct ident_split {
1034        const char *name_begin;
1035        const char *name_end;
1036        const char *mail_begin;
1037        const char *mail_end;
1038        const char *date_begin;
1039        const char *date_end;
1040        const char *tz_begin;
1041        const char *tz_end;
1042};
1043/*
1044 * Signals an success with 0, but time part of the result may be NULL
1045 * if the input lacks timestamp and zone
1046 */
1047extern int split_ident_line(struct ident_split *, const char *, int);
1048
1049/*
1050 * Compare split idents for equality or strict ordering. Note that we
1051 * compare only the ident part of the line, ignoring any timestamp.
1052 *
1053 * Because there are two fields, we must choose one as the primary key; we
1054 * currently arbitrarily pick the email.
1055 */
1056extern int ident_cmp(const struct ident_split *, const struct ident_split *);
1057
1058struct checkout {
1059        const char *base_dir;
1060        int base_dir_len;
1061        unsigned force:1,
1062                 quiet:1,
1063                 not_new:1,
1064                 refresh_cache:1;
1065};
1066
1067#define TEMPORARY_FILENAME_LENGTH 25
1068extern int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath);
1069
1070struct cache_def {
1071        char path[PATH_MAX + 1];
1072        int len;
1073        int flags;
1074        int track_flags;
1075        int prefix_len_stat_func;
1076};
1077
1078extern int has_symlink_leading_path(const char *name, int len);
1079extern int threaded_has_symlink_leading_path(struct cache_def *, const char *, int);
1080extern int check_leading_path(const char *name, int len);
1081extern int has_dirs_only_path(const char *name, int len, int prefix_len);
1082extern void schedule_dir_for_removal(const char *name, int len);
1083extern void remove_scheduled_dirs(void);
1084
1085extern struct alternate_object_database {
1086        struct alternate_object_database *next;
1087        char *name;
1088        char base[FLEX_ARRAY]; /* more */
1089} *alt_odb_list;
1090extern void prepare_alt_odb(void);
1091extern void read_info_alternates(const char * relative_base, int depth);
1092extern void add_to_alternates_file(const char *reference);
1093typedef int alt_odb_fn(struct alternate_object_database *, void *);
1094extern void foreach_alt_odb(alt_odb_fn, void*);
1095
1096struct pack_window {
1097        struct pack_window *next;
1098        unsigned char *base;
1099        off_t offset;
1100        size_t len;
1101        unsigned int last_used;
1102        unsigned int inuse_cnt;
1103};
1104
1105extern struct packed_git {
1106        struct packed_git *next;
1107        struct pack_window *windows;
1108        off_t pack_size;
1109        const void *index_data;
1110        size_t index_size;
1111        uint32_t num_objects;
1112        uint32_t num_bad_objects;
1113        unsigned char *bad_object_sha1;
1114        int index_version;
1115        time_t mtime;
1116        int pack_fd;
1117        unsigned pack_local:1,
1118                 pack_keep:1,
1119                 do_not_close:1;
1120        unsigned char sha1[20];
1121        /* something like ".git/objects/pack/xxxxx.pack" */
1122        char pack_name[FLEX_ARRAY]; /* more */
1123} *packed_git;
1124
1125struct pack_entry {
1126        off_t offset;
1127        unsigned char sha1[20];
1128        struct packed_git *p;
1129};
1130
1131extern struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
1132
1133/* A hook for count-objects to report invalid files in pack directory */
1134extern void (*report_garbage)(const char *desc, const char *path);
1135
1136extern void prepare_packed_git(void);
1137extern void reprepare_packed_git(void);
1138extern void install_packed_git(struct packed_git *pack);
1139
1140extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
1141                                         struct packed_git *packs);
1142
1143extern void pack_report(void);
1144
1145/*
1146 * mmap the index file for the specified packfile (if it is not
1147 * already mmapped).  Return 0 on success.
1148 */
1149extern int open_pack_index(struct packed_git *);
1150
1151/*
1152 * munmap the index file for the specified packfile (if it is
1153 * currently mmapped).
1154 */
1155extern void close_pack_index(struct packed_git *);
1156
1157extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
1158extern void close_pack_windows(struct packed_git *);
1159extern void unuse_pack(struct pack_window **);
1160extern void free_pack_by_name(const char *);
1161extern void clear_delta_base_cache(void);
1162extern struct packed_git *add_packed_git(const char *, int, int);
1163
1164/*
1165 * Return the SHA-1 of the nth object within the specified packfile.
1166 * Open the index if it is not already open.  The return value points
1167 * at the SHA-1 within the mmapped index.  Return NULL if there is an
1168 * error.
1169 */
1170extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
1171
1172/*
1173 * Return the offset of the nth object within the specified packfile.
1174 * The index must already be opened.
1175 */
1176extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
1177
1178/*
1179 * If the object named sha1 is present in the specified packfile,
1180 * return its offset within the packfile; otherwise, return 0.
1181 */
1182extern off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
1183
1184extern int is_pack_valid(struct packed_git *);
1185extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
1186extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
1187extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
1188extern int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
1189
1190struct object_info {
1191        /* Request */
1192        enum object_type *typep;
1193        unsigned long *sizep;
1194        unsigned long *disk_sizep;
1195        unsigned char *delta_base_sha1;
1196
1197        /* Response */
1198        enum {
1199                OI_CACHED,
1200                OI_LOOSE,
1201                OI_PACKED,
1202                OI_DBCACHED
1203        } whence;
1204        union {
1205                /*
1206                 * struct {
1207                 *      ... Nothing to expose in this case
1208                 * } cached;
1209                 * struct {
1210                 *      ... Nothing to expose in this case
1211                 * } loose;
1212                 */
1213                struct {
1214                        struct packed_git *pack;
1215                        off_t offset;
1216                        unsigned int is_delta;
1217                } packed;
1218        } u;
1219};
1220extern int sha1_object_info_extended(const unsigned char *, struct object_info *, unsigned flags);
1221
1222/* Dumb servers support */
1223extern int update_server_info(int);
1224
1225/* git_config_parse_key() returns these negated: */
1226#define CONFIG_INVALID_KEY 1
1227#define CONFIG_NO_SECTION_OR_NAME 2
1228/* git_config_set(), git_config_set_multivar() return the above or these: */
1229#define CONFIG_NO_LOCK -1
1230#define CONFIG_INVALID_FILE 3
1231#define CONFIG_NO_WRITE 4
1232#define CONFIG_NOTHING_SET 5
1233#define CONFIG_INVALID_PATTERN 6
1234#define CONFIG_GENERIC_ERROR 7
1235
1236struct git_config_source {
1237        unsigned int use_stdin:1;
1238        const char *file;
1239        const char *blob;
1240};
1241
1242typedef int (*config_fn_t)(const char *, const char *, void *);
1243extern int git_default_config(const char *, const char *, void *);
1244extern int git_config_from_file(config_fn_t fn, const char *, void *);
1245extern int git_config_from_buf(config_fn_t fn, const char *name,
1246                               const char *buf, size_t len, void *data);
1247extern void git_config_push_parameter(const char *text);
1248extern int git_config_from_parameters(config_fn_t fn, void *data);
1249extern int git_config(config_fn_t fn, void *);
1250extern int git_config_with_options(config_fn_t fn, void *,
1251                                   struct git_config_source *config_source,
1252                                   int respect_includes);
1253extern int git_config_early(config_fn_t fn, void *, const char *repo_config);
1254extern int git_parse_ulong(const char *, unsigned long *);
1255extern int git_config_int(const char *, const char *);
1256extern int64_t git_config_int64(const char *, const char *);
1257extern unsigned long git_config_ulong(const char *, const char *);
1258extern int git_config_bool_or_int(const char *, const char *, int *);
1259extern int git_config_bool(const char *, const char *);
1260extern int git_config_maybe_bool(const char *, const char *);
1261extern int git_config_string(const char **, const char *, const char *);
1262extern int git_config_pathname(const char **, const char *, const char *);
1263extern int git_config_set_in_file(const char *, const char *, const char *);
1264extern int git_config_set(const char *, const char *);
1265extern int git_config_parse_key(const char *, char **, int *);
1266extern int git_config_set_multivar(const char *, const char *, const char *, int);
1267extern int git_config_set_multivar_in_file(const char *, const char *, const char *, const char *, int);
1268extern int git_config_rename_section(const char *, const char *);
1269extern int git_config_rename_section_in_file(const char *, const char *, const char *);
1270extern const char *git_etc_gitconfig(void);
1271extern int check_repository_format_version(const char *var, const char *value, void *cb);
1272extern int git_env_bool(const char *, int);
1273extern int git_config_system(void);
1274extern int config_error_nonbool(const char *);
1275#if defined(__GNUC__) && ! defined(__clang__)
1276#define config_error_nonbool(s) (config_error_nonbool(s), -1)
1277#endif
1278extern const char *get_log_output_encoding(void);
1279extern const char *get_commit_output_encoding(void);
1280
1281extern int git_config_parse_parameter(const char *, config_fn_t fn, void *data);
1282
1283struct config_include_data {
1284        int depth;
1285        config_fn_t fn;
1286        void *data;
1287};
1288#define CONFIG_INCLUDE_INIT { 0 }
1289extern int git_config_include(const char *name, const char *value, void *data);
1290
1291/*
1292 * Match and parse a config key of the form:
1293 *
1294 *   section.(subsection.)?key
1295 *
1296 * (i.e., what gets handed to a config_fn_t). The caller provides the section;
1297 * we return -1 if it does not match, 0 otherwise. The subsection and key
1298 * out-parameters are filled by the function (and subsection is NULL if it is
1299 * missing).
1300 */
1301extern int parse_config_key(const char *var,
1302                            const char *section,
1303                            const char **subsection, int *subsection_len,
1304                            const char **key);
1305
1306extern int committer_ident_sufficiently_given(void);
1307extern int author_ident_sufficiently_given(void);
1308
1309extern const char *git_commit_encoding;
1310extern const char *git_log_output_encoding;
1311extern const char *git_mailmap_file;
1312extern const char *git_mailmap_blob;
1313
1314/* IO helper functions */
1315extern void maybe_flush_or_die(FILE *, const char *);
1316extern int copy_fd(int ifd, int ofd);
1317extern int copy_file(const char *dst, const char *src, int mode);
1318extern int copy_file_with_time(const char *dst, const char *src, int mode);
1319extern void write_or_die(int fd, const void *buf, size_t count);
1320extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
1321extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
1322extern void fsync_or_die(int fd, const char *);
1323
1324extern ssize_t read_in_full(int fd, void *buf, size_t count);
1325extern ssize_t write_in_full(int fd, const void *buf, size_t count);
1326extern ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset);
1327
1328static inline ssize_t write_str_in_full(int fd, const char *str)
1329{
1330        return write_in_full(fd, str, strlen(str));
1331}
1332
1333/* pager.c */
1334extern void setup_pager(void);
1335extern const char *pager_program;
1336extern int pager_in_use(void);
1337extern int pager_use_color;
1338extern int term_columns(void);
1339extern int decimal_width(int);
1340extern int check_pager_config(const char *cmd);
1341
1342extern const char *editor_program;
1343extern const char *askpass_program;
1344extern const char *excludes_file;
1345
1346/* base85 */
1347int decode_85(char *dst, const char *line, int linelen);
1348void encode_85(char *buf, const unsigned char *data, int bytes);
1349
1350/* alloc.c */
1351extern void *alloc_blob_node(void);
1352extern void *alloc_tree_node(void);
1353extern void *alloc_commit_node(void);
1354extern void *alloc_tag_node(void);
1355extern void *alloc_object_node(void);
1356extern void alloc_report(void);
1357
1358/* trace.c */
1359__attribute__((format (printf, 1, 2)))
1360extern void trace_printf(const char *format, ...);
1361__attribute__((format (printf, 2, 3)))
1362extern void trace_argv_printf(const char **argv, const char *format, ...);
1363extern void trace_repo_setup(const char *prefix);
1364extern int trace_want(const char *key);
1365__attribute__((format (printf, 2, 3)))
1366extern void trace_printf_key(const char *key, const char *fmt, ...);
1367extern void trace_strbuf(const char *key, const struct strbuf *buf);
1368
1369void packet_trace_identity(const char *prog);
1370
1371/* add */
1372/*
1373 * return 0 if success, 1 - if addition of a file failed and
1374 * ADD_FILES_IGNORE_ERRORS was specified in flags
1375 */
1376int add_files_to_cache(const char *prefix, const struct pathspec *pathspec, int flags);
1377
1378/* diff.c */
1379extern int diff_auto_refresh_index;
1380
1381/* match-trees.c */
1382void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
1383void shift_tree_by(const unsigned char *, const unsigned char *, unsigned char *, const char *);
1384
1385/*
1386 * whitespace rules.
1387 * used by both diff and apply
1388 * last two digits are tab width
1389 */
1390#define WS_BLANK_AT_EOL         0100
1391#define WS_SPACE_BEFORE_TAB     0200
1392#define WS_INDENT_WITH_NON_TAB  0400
1393#define WS_CR_AT_EOL           01000
1394#define WS_BLANK_AT_EOF        02000
1395#define WS_TAB_IN_INDENT       04000
1396#define WS_TRAILING_SPACE      (WS_BLANK_AT_EOL|WS_BLANK_AT_EOF)
1397#define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB|8)
1398#define WS_TAB_WIDTH_MASK        077
1399extern unsigned whitespace_rule_cfg;
1400extern unsigned whitespace_rule(const char *);
1401extern unsigned parse_whitespace_rule(const char *);
1402extern unsigned ws_check(const char *line, int len, unsigned ws_rule);
1403extern void ws_check_emit(const char *line, int len, unsigned ws_rule, FILE *stream, const char *set, const char *reset, const char *ws);
1404extern char *whitespace_error_string(unsigned ws);
1405extern void ws_fix_copy(struct strbuf *, const char *, int, unsigned, int *);
1406extern int ws_blank_line(const char *line, int len, unsigned ws_rule);
1407#define ws_tab_width(rule)     ((rule) & WS_TAB_WIDTH_MASK)
1408
1409/* ls-files */
1410int report_path_error(const char *ps_matched, const struct pathspec *pathspec, const char *prefix);
1411void overlay_tree_on_cache(const char *tree_name, const char *prefix);
1412
1413char *alias_lookup(const char *alias);
1414int split_cmdline(char *cmdline, const char ***argv);
1415/* Takes a negative value returned by split_cmdline */
1416const char *split_cmdline_strerror(int cmdline_errno);
1417
1418/* git.c */
1419struct startup_info {
1420        int have_repository;
1421        const char *prefix;
1422};
1423extern struct startup_info *startup_info;
1424
1425/* merge.c */
1426struct commit_list;
1427int try_merge_command(const char *strategy, size_t xopts_nr,
1428                const char **xopts, struct commit_list *common,
1429                const char *head_arg, struct commit_list *remotes);
1430int checkout_fast_forward(const unsigned char *from,
1431                          const unsigned char *to,
1432                          int overwrite_ignore);
1433
1434
1435int sane_execvp(const char *file, char *const argv[]);
1436
1437/*
1438 * A struct to encapsulate the concept of whether a file has changed
1439 * since we last checked it. This uses criteria similar to those used
1440 * for the index.
1441 */
1442struct stat_validity {
1443        struct stat_data *sd;
1444};
1445
1446void stat_validity_clear(struct stat_validity *sv);
1447
1448/*
1449 * Returns 1 if the path is a regular file (or a symlink to a regular
1450 * file) and matches the saved stat_validity, 0 otherwise.  A missing
1451 * or inaccessible file is considered a match if the struct was just
1452 * initialized, or if the previous update found an inaccessible file.
1453 */
1454int stat_validity_check(struct stat_validity *sv, const char *path);
1455
1456/*
1457 * Update the stat_validity from a file opened at descriptor fd. If
1458 * the file is missing, inaccessible, or not a regular file, then
1459 * future calls to stat_validity_check will match iff one of those
1460 * conditions continues to be true.
1461 */
1462void stat_validity_update(struct stat_validity *sv, int fd);
1463
1464int versioncmp(const char *s1, const char *s2);
1465
1466#endif /* CACHE_H */