cache.hon commit Merge branch 'mh/object-code-cleanup' (060be00)
   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};
 283
 284extern struct index_state the_index;
 285
 286/* Name hashing */
 287extern void add_name_hash(struct index_state *istate, struct cache_entry *ce);
 288extern void remove_name_hash(struct index_state *istate, struct cache_entry *ce);
 289extern void free_name_hash(struct index_state *istate);
 290
 291
 292#ifndef NO_THE_INDEX_COMPATIBILITY_MACROS
 293#define active_cache (the_index.cache)
 294#define active_nr (the_index.cache_nr)
 295#define active_alloc (the_index.cache_alloc)
 296#define active_cache_changed (the_index.cache_changed)
 297#define active_cache_tree (the_index.cache_tree)
 298
 299#define read_cache() read_index(&the_index)
 300#define read_cache_from(path) read_index_from(&the_index, (path))
 301#define read_cache_preload(pathspec) read_index_preload(&the_index, (pathspec))
 302#define is_cache_unborn() is_index_unborn(&the_index)
 303#define read_cache_unmerged() read_index_unmerged(&the_index)
 304#define write_cache(newfd, cache, entries) write_index(&the_index, (newfd))
 305#define discard_cache() discard_index(&the_index)
 306#define unmerged_cache() unmerged_index(&the_index)
 307#define cache_name_pos(name, namelen) index_name_pos(&the_index,(name),(namelen))
 308#define add_cache_entry(ce, option) add_index_entry(&the_index, (ce), (option))
 309#define rename_cache_entry_at(pos, new_name) rename_index_entry_at(&the_index, (pos), (new_name))
 310#define remove_cache_entry_at(pos) remove_index_entry_at(&the_index, (pos))
 311#define remove_file_from_cache(path) remove_file_from_index(&the_index, (path))
 312#define add_to_cache(path, st, flags) add_to_index(&the_index, (path), (st), (flags))
 313#define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags))
 314#define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
 315#define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
 316#define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
 317#define cache_dir_exists(name, namelen) index_dir_exists(&the_index, (name), (namelen))
 318#define cache_file_exists(name, namelen, igncase) index_file_exists(&the_index, (name), (namelen), (igncase))
 319#define cache_name_is_other(name, namelen) index_name_is_other(&the_index, (name), (namelen))
 320#define resolve_undo_clear() resolve_undo_clear_index(&the_index)
 321#define unmerge_cache_entry_at(at) unmerge_index_entry_at(&the_index, at)
 322#define unmerge_cache(pathspec) unmerge_index(&the_index, pathspec)
 323#define read_blob_data_from_cache(path, sz) read_blob_data_from_index(&the_index, (path), (sz))
 324#endif
 325
 326enum object_type {
 327        OBJ_BAD = -1,
 328        OBJ_NONE = 0,
 329        OBJ_COMMIT = 1,
 330        OBJ_TREE = 2,
 331        OBJ_BLOB = 3,
 332        OBJ_TAG = 4,
 333        /* 5 for future expansion */
 334        OBJ_OFS_DELTA = 6,
 335        OBJ_REF_DELTA = 7,
 336        OBJ_ANY,
 337        OBJ_MAX
 338};
 339
 340static inline enum object_type object_type(unsigned int mode)
 341{
 342        return S_ISDIR(mode) ? OBJ_TREE :
 343                S_ISGITLINK(mode) ? OBJ_COMMIT :
 344                OBJ_BLOB;
 345}
 346
 347/* Double-check local_repo_env below if you add to this list. */
 348#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 349#define GIT_NAMESPACE_ENVIRONMENT "GIT_NAMESPACE"
 350#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
 351#define GIT_PREFIX_ENVIRONMENT "GIT_PREFIX"
 352#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 353#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 354#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 355#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 356#define GIT_SHALLOW_FILE_ENVIRONMENT "GIT_SHALLOW_FILE"
 357#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
 358#define CONFIG_ENVIRONMENT "GIT_CONFIG"
 359#define CONFIG_DATA_ENVIRONMENT "GIT_CONFIG_PARAMETERS"
 360#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 361#define CEILING_DIRECTORIES_ENVIRONMENT "GIT_CEILING_DIRECTORIES"
 362#define NO_REPLACE_OBJECTS_ENVIRONMENT "GIT_NO_REPLACE_OBJECTS"
 363#define GITATTRIBUTES_FILE ".gitattributes"
 364#define INFOATTRIBUTES_FILE "info/attributes"
 365#define ATTRIBUTE_MACRO_PREFIX "[attr]"
 366#define GIT_NOTES_REF_ENVIRONMENT "GIT_NOTES_REF"
 367#define GIT_NOTES_DEFAULT_REF "refs/notes/commits"
 368#define GIT_NOTES_DISPLAY_REF_ENVIRONMENT "GIT_NOTES_DISPLAY_REF"
 369#define GIT_NOTES_REWRITE_REF_ENVIRONMENT "GIT_NOTES_REWRITE_REF"
 370#define GIT_NOTES_REWRITE_MODE_ENVIRONMENT "GIT_NOTES_REWRITE_MODE"
 371#define GIT_LITERAL_PATHSPECS_ENVIRONMENT "GIT_LITERAL_PATHSPECS"
 372#define GIT_GLOB_PATHSPECS_ENVIRONMENT "GIT_GLOB_PATHSPECS"
 373#define GIT_NOGLOB_PATHSPECS_ENVIRONMENT "GIT_NOGLOB_PATHSPECS"
 374#define GIT_ICASE_PATHSPECS_ENVIRONMENT "GIT_ICASE_PATHSPECS"
 375
 376/*
 377 * This environment variable is expected to contain a boolean indicating
 378 * whether we should or should not treat:
 379 *
 380 *   GIT_DIR=foo.git git ...
 381 *
 382 * as if GIT_WORK_TREE=. was given. It's not expected that users will make use
 383 * of this, but we use it internally to communicate to sub-processes that we
 384 * are in a bare repo. If not set, defaults to true.
 385 */
 386#define GIT_IMPLICIT_WORK_TREE_ENVIRONMENT "GIT_IMPLICIT_WORK_TREE"
 387
 388/*
 389 * Repository-local GIT_* environment variables; these will be cleared
 390 * when git spawns a sub-process that runs inside another repository.
 391 * The array is NULL-terminated, which makes it easy to pass in the "env"
 392 * parameter of a run-command invocation, or to do a simple walk.
 393 */
 394extern const char * const local_repo_env[];
 395
 396extern int is_bare_repository_cfg;
 397extern int is_bare_repository(void);
 398extern int is_inside_git_dir(void);
 399extern char *git_work_tree_cfg;
 400extern int is_inside_work_tree(void);
 401extern const char *get_git_dir(void);
 402extern int is_git_directory(const char *path);
 403extern char *get_object_directory(void);
 404extern char *get_index_file(void);
 405extern char *get_graft_file(void);
 406extern int set_git_dir(const char *path);
 407extern const char *get_git_namespace(void);
 408extern const char *strip_namespace(const char *namespaced_ref);
 409extern const char *get_git_work_tree(void);
 410extern const char *read_gitfile(const char *path);
 411extern const char *resolve_gitdir(const char *suspect);
 412extern void set_git_work_tree(const char *tree);
 413
 414#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 415
 416extern const char **get_pathspec(const char *prefix, const char **pathspec);
 417extern void setup_work_tree(void);
 418extern const char *setup_git_directory_gently(int *);
 419extern const char *setup_git_directory(void);
 420extern char *prefix_path(const char *prefix, int len, const char *path);
 421extern char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
 422extern const char *prefix_filename(const char *prefix, int len, const char *path);
 423extern int check_filename(const char *prefix, const char *name);
 424extern void verify_filename(const char *prefix,
 425                            const char *name,
 426                            int diagnose_misspelt_rev);
 427extern void verify_non_filename(const char *prefix, const char *name);
 428extern int path_inside_repo(const char *prefix, const char *path);
 429
 430#define INIT_DB_QUIET 0x0001
 431
 432extern int set_git_dir_init(const char *git_dir, const char *real_git_dir, int);
 433extern int init_db(const char *template_dir, unsigned int flags);
 434
 435extern void sanitize_stdfds(void);
 436extern int daemonize(void);
 437
 438#define alloc_nr(x) (((x)+16)*3/2)
 439
 440/*
 441 * Realloc the buffer pointed at by variable 'x' so that it can hold
 442 * at least 'nr' entries; the number of entries currently allocated
 443 * is 'alloc', using the standard growing factor alloc_nr() macro.
 444 *
 445 * DO NOT USE any expression with side-effect for 'x', 'nr', or 'alloc'.
 446 */
 447#define ALLOC_GROW(x, nr, alloc) \
 448        do { \
 449                if ((nr) > alloc) { \
 450                        if (alloc_nr(alloc) < (nr)) \
 451                                alloc = (nr); \
 452                        else \
 453                                alloc = alloc_nr(alloc); \
 454                        x = xrealloc((x), alloc * sizeof(*(x))); \
 455                } \
 456        } while (0)
 457
 458/* Initialize and use the cache information */
 459extern int read_index(struct index_state *);
 460extern int read_index_preload(struct index_state *, const struct pathspec *pathspec);
 461extern int read_index_from(struct index_state *, const char *path);
 462extern int is_index_unborn(struct index_state *);
 463extern int read_index_unmerged(struct index_state *);
 464extern int write_index(struct index_state *, int newfd);
 465extern int discard_index(struct index_state *);
 466extern int unmerged_index(const struct index_state *);
 467extern int verify_path(const char *path);
 468extern struct cache_entry *index_dir_exists(struct index_state *istate, const char *name, int namelen);
 469extern struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 470extern int index_name_pos(const struct index_state *, const char *name, int namelen);
 471#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 472#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 473#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 474#define ADD_CACHE_JUST_APPEND 8         /* Append only; tree.c::read_tree() */
 475#define ADD_CACHE_NEW_ONLY 16           /* Do not replace existing ones */
 476extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
 477extern void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
 478extern int remove_index_entry_at(struct index_state *, int pos);
 479extern void remove_marked_cache_entries(struct index_state *istate);
 480extern int remove_file_from_index(struct index_state *, const char *path);
 481#define ADD_CACHE_VERBOSE 1
 482#define ADD_CACHE_PRETEND 2
 483#define ADD_CACHE_IGNORE_ERRORS 4
 484#define ADD_CACHE_IGNORE_REMOVAL 8
 485#define ADD_CACHE_INTENT 16
 486extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
 487extern int add_file_to_index(struct index_state *, const char *path, int flags);
 488extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, unsigned int refresh_options);
 489extern int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
 490extern void set_object_name_for_intent_to_add_entry(struct cache_entry *ce);
 491extern int index_name_is_other(const struct index_state *, const char *, int);
 492extern void *read_blob_data_from_index(struct index_state *, const char *, unsigned long *);
 493
 494/* do stat comparison even if CE_VALID is true */
 495#define CE_MATCH_IGNORE_VALID           01
 496/* do not check the contents but report dirty on racily-clean entries */
 497#define CE_MATCH_RACY_IS_DIRTY          02
 498/* do stat comparison even if CE_SKIP_WORKTREE is true */
 499#define CE_MATCH_IGNORE_SKIP_WORKTREE   04
 500/* ignore non-existent files during stat update  */
 501#define CE_MATCH_IGNORE_MISSING         0x08
 502/* enable stat refresh */
 503#define CE_MATCH_REFRESH                0x10
 504extern int ie_match_stat(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 505extern int ie_modified(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 506
 507#define HASH_WRITE_OBJECT 1
 508#define HASH_FORMAT_CHECK 2
 509extern int index_fd(unsigned char *sha1, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
 510extern int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags);
 511
 512/*
 513 * Record to sd the data from st that we use to check whether a file
 514 * might have changed.
 515 */
 516extern void fill_stat_data(struct stat_data *sd, struct stat *st);
 517
 518/*
 519 * Return 0 if st is consistent with a file not having been changed
 520 * since sd was filled.  If there are differences, return a
 521 * combination of MTIME_CHANGED, CTIME_CHANGED, OWNER_CHANGED,
 522 * INODE_CHANGED, and DATA_CHANGED.
 523 */
 524extern int match_stat_data(const struct stat_data *sd, struct stat *st);
 525
 526extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 527
 528#define REFRESH_REALLY          0x0001  /* ignore_valid */
 529#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 530#define REFRESH_QUIET           0x0004  /* be quiet about it */
 531#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 532#define REFRESH_IGNORE_SUBMODULES       0x0010  /* ignore submodules */
 533#define REFRESH_IN_PORCELAIN    0x0020  /* user friendly output, not "needs update" */
 534extern int refresh_index(struct index_state *, unsigned int flags, const struct pathspec *pathspec, char *seen, const char *header_msg);
 535
 536struct lock_file {
 537        struct lock_file *next;
 538        int fd;
 539        pid_t owner;
 540        char on_list;
 541        char filename[PATH_MAX];
 542};
 543#define LOCK_DIE_ON_ERROR 1
 544#define LOCK_NODEREF 2
 545extern int unable_to_lock_error(const char *path, int err);
 546extern NORETURN void unable_to_lock_index_die(const char *path, int err);
 547extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 548extern int hold_lock_file_for_append(struct lock_file *, const char *path, int);
 549extern int commit_lock_file(struct lock_file *);
 550extern void update_index_if_able(struct index_state *, struct lock_file *);
 551
 552extern int hold_locked_index(struct lock_file *, int);
 553extern int commit_locked_index(struct lock_file *);
 554extern void set_alternate_index_output(const char *);
 555extern int close_lock_file(struct lock_file *);
 556extern void rollback_lock_file(struct lock_file *);
 557extern int delete_ref(const char *, const unsigned char *sha1, int delopt);
 558
 559/* Environment bits from configuration mechanism */
 560extern int trust_executable_bit;
 561extern int trust_ctime;
 562extern int check_stat;
 563extern int quote_path_fully;
 564extern int has_symlinks;
 565extern int minimum_abbrev, default_abbrev;
 566extern int ignore_case;
 567extern int assume_unchanged;
 568extern int prefer_symlink_refs;
 569extern int log_all_ref_updates;
 570extern int warn_ambiguous_refs;
 571extern int warn_on_object_refname_ambiguity;
 572extern int shared_repository;
 573extern const char *apply_default_whitespace;
 574extern const char *apply_default_ignorewhitespace;
 575extern const char *git_attributes_file;
 576extern int zlib_compression_level;
 577extern int core_compression_level;
 578extern int core_compression_seen;
 579extern size_t packed_git_window_size;
 580extern size_t packed_git_limit;
 581extern size_t delta_base_cache_limit;
 582extern unsigned long big_file_threshold;
 583extern unsigned long pack_size_limit_cfg;
 584extern int read_replace_refs;
 585extern int fsync_object_files;
 586extern int core_preload_index;
 587extern int core_apply_sparse_checkout;
 588extern int precomposed_unicode;
 589
 590/*
 591 * The character that begins a commented line in user-editable file
 592 * that is subject to stripspace.
 593 */
 594extern char comment_line_char;
 595
 596enum branch_track {
 597        BRANCH_TRACK_UNSPECIFIED = -1,
 598        BRANCH_TRACK_NEVER = 0,
 599        BRANCH_TRACK_REMOTE,
 600        BRANCH_TRACK_ALWAYS,
 601        BRANCH_TRACK_EXPLICIT,
 602        BRANCH_TRACK_OVERRIDE
 603};
 604
 605enum rebase_setup_type {
 606        AUTOREBASE_NEVER = 0,
 607        AUTOREBASE_LOCAL,
 608        AUTOREBASE_REMOTE,
 609        AUTOREBASE_ALWAYS
 610};
 611
 612enum push_default_type {
 613        PUSH_DEFAULT_NOTHING = 0,
 614        PUSH_DEFAULT_MATCHING,
 615        PUSH_DEFAULT_SIMPLE,
 616        PUSH_DEFAULT_UPSTREAM,
 617        PUSH_DEFAULT_CURRENT,
 618        PUSH_DEFAULT_UNSPECIFIED
 619};
 620
 621extern enum branch_track git_branch_track;
 622extern enum rebase_setup_type autorebase;
 623extern enum push_default_type push_default;
 624
 625enum object_creation_mode {
 626        OBJECT_CREATION_USES_HARDLINKS = 0,
 627        OBJECT_CREATION_USES_RENAMES = 1
 628};
 629
 630extern enum object_creation_mode object_creation_mode;
 631
 632extern char *notes_ref_name;
 633
 634extern int grafts_replace_parents;
 635
 636#define GIT_REPO_VERSION 0
 637extern int repository_format_version;
 638extern int check_repository_format(void);
 639
 640#define MTIME_CHANGED   0x0001
 641#define CTIME_CHANGED   0x0002
 642#define OWNER_CHANGED   0x0004
 643#define MODE_CHANGED    0x0008
 644#define INODE_CHANGED   0x0010
 645#define DATA_CHANGED    0x0020
 646#define TYPE_CHANGED    0x0040
 647
 648extern char *mksnpath(char *buf, size_t n, const char *fmt, ...)
 649        __attribute__((format (printf, 3, 4)));
 650extern char *git_snpath(char *buf, size_t n, const char *fmt, ...)
 651        __attribute__((format (printf, 3, 4)));
 652extern char *git_pathdup(const char *fmt, ...)
 653        __attribute__((format (printf, 1, 2)));
 654extern char *mkpathdup(const char *fmt, ...)
 655        __attribute__((format (printf, 1, 2)));
 656
 657/* Return a statically allocated filename matching the sha1 signature */
 658extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 659extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 660extern char *git_path_submodule(const char *path, const char *fmt, ...)
 661        __attribute__((format (printf, 2, 3)));
 662
 663/*
 664 * Return the name of the file in the local object database that would
 665 * be used to store a loose object with the specified sha1.  The
 666 * return value is a pointer to a statically allocated buffer that is
 667 * overwritten each time the function is called.
 668 */
 669extern const char *sha1_file_name(const unsigned char *sha1);
 670
 671/*
 672 * Return the name of the (local) packfile with the specified sha1 in
 673 * its name.  The return value is a pointer to memory that is
 674 * overwritten each time this function is called.
 675 */
 676extern char *sha1_pack_name(const unsigned char *sha1);
 677
 678/*
 679 * Return the name of the (local) pack index file with the specified
 680 * sha1 in its name.  The return value is a pointer to memory that is
 681 * overwritten each time this function is called.
 682 */
 683extern char *sha1_pack_index_name(const unsigned char *sha1);
 684
 685extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 686extern const unsigned char null_sha1[20];
 687
 688static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 689{
 690        int i;
 691
 692        for (i = 0; i < 20; i++, sha1++, sha2++) {
 693                if (*sha1 != *sha2)
 694                        return *sha1 - *sha2;
 695        }
 696
 697        return 0;
 698}
 699
 700static inline int is_null_sha1(const unsigned char *sha1)
 701{
 702        return !hashcmp(sha1, null_sha1);
 703}
 704
 705static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
 706{
 707        memcpy(sha_dst, sha_src, 20);
 708}
 709static inline void hashclr(unsigned char *hash)
 710{
 711        memset(hash, 0, 20);
 712}
 713
 714#define EMPTY_TREE_SHA1_HEX \
 715        "4b825dc642cb6eb9a060e54bf8d69288fbee4904"
 716#define EMPTY_TREE_SHA1_BIN_LITERAL \
 717         "\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
 718         "\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
 719#define EMPTY_TREE_SHA1_BIN \
 720         ((const unsigned char *) EMPTY_TREE_SHA1_BIN_LITERAL)
 721
 722#define EMPTY_BLOB_SHA1_HEX \
 723        "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"
 724#define EMPTY_BLOB_SHA1_BIN_LITERAL \
 725        "\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
 726        "\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
 727#define EMPTY_BLOB_SHA1_BIN \
 728        ((const unsigned char *) EMPTY_BLOB_SHA1_BIN_LITERAL)
 729
 730static inline int is_empty_blob_sha1(const unsigned char *sha1)
 731{
 732        return !hashcmp(sha1, EMPTY_BLOB_SHA1_BIN);
 733}
 734
 735int git_mkstemp(char *path, size_t n, const char *template);
 736
 737int git_mkstemps(char *path, size_t n, const char *template, int suffix_len);
 738
 739/* set default permissions by passing mode arguments to open(2) */
 740int git_mkstemps_mode(char *pattern, int suffix_len, int mode);
 741int git_mkstemp_mode(char *pattern, int mode);
 742
 743/*
 744 * NOTE NOTE NOTE!!
 745 *
 746 * PERM_UMASK, OLD_PERM_GROUP and OLD_PERM_EVERYBODY enumerations must
 747 * not be changed. Old repositories have core.sharedrepository written in
 748 * numeric format, and therefore these values are preserved for compatibility
 749 * reasons.
 750 */
 751enum sharedrepo {
 752        PERM_UMASK          = 0,
 753        OLD_PERM_GROUP      = 1,
 754        OLD_PERM_EVERYBODY  = 2,
 755        PERM_GROUP          = 0660,
 756        PERM_EVERYBODY      = 0664
 757};
 758int git_config_perm(const char *var, const char *value);
 759int adjust_shared_perm(const char *path);
 760
 761/*
 762 * Create the directory containing the named path, using care to be
 763 * somewhat safe against races.  Return one of the scld_error values
 764 * to indicate success/failure.
 765 *
 766 * SCLD_VANISHED indicates that one of the ancestor directories of the
 767 * path existed at one point during the function call and then
 768 * suddenly vanished, probably because another process pruned the
 769 * directory while we were working.  To be robust against this kind of
 770 * race, callers might want to try invoking the function again when it
 771 * returns SCLD_VANISHED.
 772 */
 773enum scld_error {
 774        SCLD_OK = 0,
 775        SCLD_FAILED = -1,
 776        SCLD_PERMS = -2,
 777        SCLD_EXISTS = -3,
 778        SCLD_VANISHED = -4
 779};
 780enum scld_error safe_create_leading_directories(char *path);
 781enum scld_error safe_create_leading_directories_const(const char *path);
 782
 783int mkdir_in_gitdir(const char *path);
 784extern void home_config_paths(char **global, char **xdg, char *file);
 785extern char *expand_user_path(const char *path);
 786const char *enter_repo(const char *path, int strict);
 787static inline int is_absolute_path(const char *path)
 788{
 789        return is_dir_sep(path[0]) || has_dos_drive_prefix(path);
 790}
 791int is_directory(const char *);
 792const char *real_path(const char *path);
 793const char *real_path_if_valid(const char *path);
 794const char *absolute_path(const char *path);
 795const char *remove_leading_path(const char *in, const char *prefix);
 796const char *relative_path(const char *in, const char *prefix, struct strbuf *sb);
 797int normalize_path_copy_len(char *dst, const char *src, int *prefix_len);
 798int normalize_path_copy(char *dst, const char *src);
 799int longest_ancestor_length(const char *path, struct string_list *prefixes);
 800char *strip_path_suffix(const char *path, const char *suffix);
 801int daemon_avoid_alias(const char *path);
 802int offset_1st_component(const char *path);
 803
 804/* object replacement */
 805#define LOOKUP_REPLACE_OBJECT 1
 806extern void *read_sha1_file_extended(const unsigned char *sha1, enum object_type *type, unsigned long *size, unsigned flag);
 807static inline void *read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 808{
 809        return read_sha1_file_extended(sha1, type, size, LOOKUP_REPLACE_OBJECT);
 810}
 811extern const unsigned char *do_lookup_replace_object(const unsigned char *sha1);
 812static inline const unsigned char *lookup_replace_object(const unsigned char *sha1)
 813{
 814        if (!read_replace_refs)
 815                return sha1;
 816        return do_lookup_replace_object(sha1);
 817}
 818static inline const unsigned char *lookup_replace_object_extended(const unsigned char *sha1, unsigned flag)
 819{
 820        if (!(flag & LOOKUP_REPLACE_OBJECT))
 821                return sha1;
 822        return lookup_replace_object(sha1);
 823}
 824
 825/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 826extern int sha1_object_info(const unsigned char *, unsigned long *);
 827extern int hash_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1);
 828extern int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 829extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
 830extern int force_object_loose(const unsigned char *sha1, time_t mtime);
 831extern int git_open_noatime(const char *name);
 832extern void *map_sha1_file(const unsigned char *sha1, unsigned long *size);
 833extern int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz);
 834extern int parse_sha1_header(const char *hdr, unsigned long *sizep);
 835
 836/* global flag to enable extra checks when accessing packed objects */
 837extern int do_check_packed_object_crc;
 838
 839extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 840
 841extern int move_temp_to_file(const char *tmpfile, const char *filename);
 842
 843extern int has_sha1_pack(const unsigned char *sha1);
 844
 845/*
 846 * Return true iff we have an object named sha1, whether local or in
 847 * an alternate object database, and whether packed or loose.  This
 848 * function does not respect replace references.
 849 */
 850extern int has_sha1_file(const unsigned char *sha1);
 851
 852/*
 853 * Return true iff an alternate object database has a loose object
 854 * with the specified name.  This function does not respect replace
 855 * references.
 856 */
 857extern int has_loose_object_nonlocal(const unsigned char *sha1);
 858
 859extern int has_pack_index(const unsigned char *sha1);
 860
 861extern void assert_sha1_type(const unsigned char *sha1, enum object_type expect);
 862
 863extern const signed char hexval_table[256];
 864static inline unsigned int hexval(unsigned char c)
 865{
 866        return hexval_table[c];
 867}
 868
 869/* Convert to/from hex/sha1 representation */
 870#define MINIMUM_ABBREV minimum_abbrev
 871#define DEFAULT_ABBREV default_abbrev
 872
 873struct object_context {
 874        unsigned char tree[20];
 875        char path[PATH_MAX];
 876        unsigned mode;
 877};
 878
 879#define GET_SHA1_QUIETLY        01
 880#define GET_SHA1_COMMIT         02
 881#define GET_SHA1_COMMITTISH     04
 882#define GET_SHA1_TREE          010
 883#define GET_SHA1_TREEISH       020
 884#define GET_SHA1_BLOB          040
 885#define GET_SHA1_ONLY_TO_DIE 04000
 886
 887extern int get_sha1(const char *str, unsigned char *sha1);
 888extern int get_sha1_commit(const char *str, unsigned char *sha1);
 889extern int get_sha1_committish(const char *str, unsigned char *sha1);
 890extern int get_sha1_tree(const char *str, unsigned char *sha1);
 891extern int get_sha1_treeish(const char *str, unsigned char *sha1);
 892extern int get_sha1_blob(const char *str, unsigned char *sha1);
 893extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
 894extern int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc);
 895
 896typedef int each_abbrev_fn(const unsigned char *sha1, void *);
 897extern int for_each_abbrev(const char *prefix, each_abbrev_fn, void *);
 898
 899/*
 900 * Try to read a SHA1 in hexadecimal format from the 40 characters
 901 * starting at hex.  Write the 20-byte result to sha1 in binary form.
 902 * Return 0 on success.  Reading stops if a NUL is encountered in the
 903 * input, so it is safe to pass this function an arbitrary
 904 * null-terminated string.
 905 */
 906extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 907
 908extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 909extern int read_ref_full(const char *refname, unsigned char *sha1,
 910                         int reading, int *flags);
 911extern int read_ref(const char *refname, unsigned char *sha1);
 912
 913/*
 914 * Resolve a reference, recursively following symbolic refererences.
 915 *
 916 * Store the referred-to object's name in sha1 and return the name of
 917 * the non-symbolic reference that ultimately pointed at it.  The
 918 * return value, if not NULL, is a pointer into either a static buffer
 919 * or the input ref.
 920 *
 921 * If the reference cannot be resolved to an object, the behavior
 922 * depends on the "reading" argument:
 923 *
 924 * - If reading is set, return NULL.
 925 *
 926 * - If reading is not set, clear sha1 and return the name of the last
 927 *   reference name in the chain, which will either be a non-symbolic
 928 *   reference or an undefined reference.  If this is a prelude to
 929 *   "writing" to the ref, the return value is the name of the ref
 930 *   that will actually be created or changed.
 931 *
 932 * If flag is non-NULL, set the value that it points to the
 933 * combination of REF_ISPACKED (if the reference was found among the
 934 * packed references) and REF_ISSYMREF (if the initial reference was a
 935 * symbolic reference).
 936 *
 937 * If ref is not a properly-formatted, normalized reference, return
 938 * NULL.  If more than MAXDEPTH recursive symbolic lookups are needed,
 939 * give up and return NULL.
 940 *
 941 * errno is sometimes set on errors, but not always.
 942 */
 943extern const char *resolve_ref_unsafe(const char *ref, unsigned char *sha1, int reading, int *flag);
 944extern char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag);
 945
 946extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
 947extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
 948extern int interpret_branch_name(const char *str, int len, struct strbuf *);
 949extern int get_sha1_mb(const char *str, unsigned char *sha1);
 950
 951/*
 952 * Return true iff abbrev_name is a possible abbreviation for
 953 * full_name according to the rules defined by ref_rev_parse_rules in
 954 * refs.c.
 955 */
 956extern int refname_match(const char *abbrev_name, const char *full_name);
 957
 958extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
 959extern int validate_headref(const char *ref);
 960
 961extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 962extern int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 963extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 964extern int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2);
 965
 966extern void *read_object_with_reference(const unsigned char *sha1,
 967                                        const char *required_type,
 968                                        unsigned long *size,
 969                                        unsigned char *sha1_ret);
 970
 971extern struct object *peel_to_type(const char *name, int namelen,
 972                                   struct object *o, enum object_type);
 973
 974enum date_mode {
 975        DATE_NORMAL = 0,
 976        DATE_RELATIVE,
 977        DATE_SHORT,
 978        DATE_LOCAL,
 979        DATE_ISO8601,
 980        DATE_RFC2822,
 981        DATE_RAW
 982};
 983
 984const char *show_date(unsigned long time, int timezone, enum date_mode mode);
 985void show_date_relative(unsigned long time, int tz, const struct timeval *now,
 986                        struct strbuf *timebuf);
 987int parse_date(const char *date, char *buf, int bufsize);
 988int parse_date_basic(const char *date, unsigned long *timestamp, int *offset);
 989int parse_expiry_date(const char *date, unsigned long *timestamp);
 990void datestamp(char *buf, int bufsize);
 991#define approxidate(s) approxidate_careful((s), NULL)
 992unsigned long approxidate_careful(const char *, int *);
 993unsigned long approxidate_relative(const char *date, const struct timeval *now);
 994enum date_mode parse_date_format(const char *format);
 995int date_overflows(unsigned long date);
 996
 997#define IDENT_STRICT           1
 998#define IDENT_NO_DATE          2
 999#define IDENT_NO_NAME          4
1000extern const char *git_author_info(int);
1001extern const char *git_committer_info(int);
1002extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
1003extern const char *fmt_name(const char *name, const char *email);
1004extern const char *ident_default_email(void);
1005extern const char *git_editor(void);
1006extern const char *git_pager(int stdout_is_tty);
1007extern int git_ident_config(const char *, const char *, void *);
1008
1009struct ident_split {
1010        const char *name_begin;
1011        const char *name_end;
1012        const char *mail_begin;
1013        const char *mail_end;
1014        const char *date_begin;
1015        const char *date_end;
1016        const char *tz_begin;
1017        const char *tz_end;
1018};
1019/*
1020 * Signals an success with 0, but time part of the result may be NULL
1021 * if the input lacks timestamp and zone
1022 */
1023extern int split_ident_line(struct ident_split *, const char *, int);
1024
1025/*
1026 * Compare split idents for equality or strict ordering. Note that we
1027 * compare only the ident part of the line, ignoring any timestamp.
1028 *
1029 * Because there are two fields, we must choose one as the primary key; we
1030 * currently arbitrarily pick the email.
1031 */
1032extern int ident_cmp(const struct ident_split *, const struct ident_split *);
1033
1034struct checkout {
1035        const char *base_dir;
1036        int base_dir_len;
1037        unsigned force:1,
1038                 quiet:1,
1039                 not_new:1,
1040                 refresh_cache:1;
1041};
1042
1043#define TEMPORARY_FILENAME_LENGTH 25
1044extern int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath);
1045
1046struct cache_def {
1047        char path[PATH_MAX + 1];
1048        int len;
1049        int flags;
1050        int track_flags;
1051        int prefix_len_stat_func;
1052};
1053
1054extern int has_symlink_leading_path(const char *name, int len);
1055extern int threaded_has_symlink_leading_path(struct cache_def *, const char *, int);
1056extern int check_leading_path(const char *name, int len);
1057extern int has_dirs_only_path(const char *name, int len, int prefix_len);
1058extern void schedule_dir_for_removal(const char *name, int len);
1059extern void remove_scheduled_dirs(void);
1060
1061extern struct alternate_object_database {
1062        struct alternate_object_database *next;
1063        char *name;
1064        char base[FLEX_ARRAY]; /* more */
1065} *alt_odb_list;
1066extern void prepare_alt_odb(void);
1067extern void read_info_alternates(const char * relative_base, int depth);
1068extern void add_to_alternates_file(const char *reference);
1069typedef int alt_odb_fn(struct alternate_object_database *, void *);
1070extern void foreach_alt_odb(alt_odb_fn, void*);
1071
1072struct pack_window {
1073        struct pack_window *next;
1074        unsigned char *base;
1075        off_t offset;
1076        size_t len;
1077        unsigned int last_used;
1078        unsigned int inuse_cnt;
1079};
1080
1081extern struct packed_git {
1082        struct packed_git *next;
1083        struct pack_window *windows;
1084        off_t pack_size;
1085        const void *index_data;
1086        size_t index_size;
1087        uint32_t num_objects;
1088        uint32_t num_bad_objects;
1089        unsigned char *bad_object_sha1;
1090        int index_version;
1091        time_t mtime;
1092        int pack_fd;
1093        unsigned pack_local:1,
1094                 pack_keep:1,
1095                 do_not_close:1;
1096        unsigned char sha1[20];
1097        /* something like ".git/objects/pack/xxxxx.pack" */
1098        char pack_name[FLEX_ARRAY]; /* more */
1099} *packed_git;
1100
1101struct pack_entry {
1102        off_t offset;
1103        unsigned char sha1[20];
1104        struct packed_git *p;
1105};
1106
1107extern struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
1108
1109/* A hook for count-objects to report invalid files in pack directory */
1110extern void (*report_garbage)(const char *desc, const char *path);
1111
1112extern void prepare_packed_git(void);
1113extern void reprepare_packed_git(void);
1114extern void install_packed_git(struct packed_git *pack);
1115
1116extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
1117                                         struct packed_git *packs);
1118
1119extern void pack_report(void);
1120
1121/*
1122 * mmap the index file for the specified packfile (if it is not
1123 * already mmapped).  Return 0 on success.
1124 */
1125extern int open_pack_index(struct packed_git *);
1126
1127/*
1128 * munmap the index file for the specified packfile (if it is
1129 * currently mmapped).
1130 */
1131extern void close_pack_index(struct packed_git *);
1132
1133extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
1134extern void close_pack_windows(struct packed_git *);
1135extern void unuse_pack(struct pack_window **);
1136extern void free_pack_by_name(const char *);
1137extern void clear_delta_base_cache(void);
1138extern struct packed_git *add_packed_git(const char *, int, int);
1139
1140/*
1141 * Return the SHA-1 of the nth object within the specified packfile.
1142 * Open the index if it is not already open.  The return value points
1143 * at the SHA-1 within the mmapped index.  Return NULL if there is an
1144 * error.
1145 */
1146extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
1147
1148/*
1149 * Return the offset of the nth object within the specified packfile.
1150 * The index must already be opened.
1151 */
1152extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
1153
1154/*
1155 * If the object named sha1 is present in the specified packfile,
1156 * return its offset within the packfile; otherwise, return 0.
1157 */
1158extern off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
1159
1160extern int is_pack_valid(struct packed_git *);
1161extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
1162extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
1163extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
1164extern int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
1165
1166struct object_info {
1167        /* Request */
1168        enum object_type *typep;
1169        unsigned long *sizep;
1170        unsigned long *disk_sizep;
1171        unsigned char *delta_base_sha1;
1172
1173        /* Response */
1174        enum {
1175                OI_CACHED,
1176                OI_LOOSE,
1177                OI_PACKED,
1178                OI_DBCACHED
1179        } whence;
1180        union {
1181                /*
1182                 * struct {
1183                 *      ... Nothing to expose in this case
1184                 * } cached;
1185                 * struct {
1186                 *      ... Nothing to expose in this case
1187                 * } loose;
1188                 */
1189                struct {
1190                        struct packed_git *pack;
1191                        off_t offset;
1192                        unsigned int is_delta;
1193                } packed;
1194        } u;
1195};
1196extern int sha1_object_info_extended(const unsigned char *, struct object_info *, unsigned flags);
1197
1198/* Dumb servers support */
1199extern int update_server_info(int);
1200
1201/* git_config_parse_key() returns these negated: */
1202#define CONFIG_INVALID_KEY 1
1203#define CONFIG_NO_SECTION_OR_NAME 2
1204/* git_config_set(), git_config_set_multivar() return the above or these: */
1205#define CONFIG_NO_LOCK -1
1206#define CONFIG_INVALID_FILE 3
1207#define CONFIG_NO_WRITE 4
1208#define CONFIG_NOTHING_SET 5
1209#define CONFIG_INVALID_PATTERN 6
1210#define CONFIG_GENERIC_ERROR 7
1211
1212struct git_config_source {
1213        unsigned int use_stdin:1;
1214        const char *file;
1215        const char *blob;
1216};
1217
1218typedef int (*config_fn_t)(const char *, const char *, void *);
1219extern int git_default_config(const char *, const char *, void *);
1220extern int git_config_from_file(config_fn_t fn, const char *, void *);
1221extern int git_config_from_buf(config_fn_t fn, const char *name,
1222                               const char *buf, size_t len, void *data);
1223extern void git_config_push_parameter(const char *text);
1224extern int git_config_from_parameters(config_fn_t fn, void *data);
1225extern int git_config(config_fn_t fn, void *);
1226extern int git_config_with_options(config_fn_t fn, void *,
1227                                   struct git_config_source *config_source,
1228                                   int respect_includes);
1229extern int git_config_early(config_fn_t fn, void *, const char *repo_config);
1230extern int git_parse_ulong(const char *, unsigned long *);
1231extern int git_config_int(const char *, const char *);
1232extern int64_t git_config_int64(const char *, const char *);
1233extern unsigned long git_config_ulong(const char *, const char *);
1234extern int git_config_bool_or_int(const char *, const char *, int *);
1235extern int git_config_bool(const char *, const char *);
1236extern int git_config_maybe_bool(const char *, const char *);
1237extern int git_config_string(const char **, const char *, const char *);
1238extern int git_config_pathname(const char **, const char *, const char *);
1239extern int git_config_set_in_file(const char *, const char *, const char *);
1240extern int git_config_set(const char *, const char *);
1241extern int git_config_parse_key(const char *, char **, int *);
1242extern int git_config_set_multivar(const char *, const char *, const char *, int);
1243extern int git_config_set_multivar_in_file(const char *, const char *, const char *, const char *, int);
1244extern int git_config_rename_section(const char *, const char *);
1245extern int git_config_rename_section_in_file(const char *, const char *, const char *);
1246extern const char *git_etc_gitconfig(void);
1247extern int check_repository_format_version(const char *var, const char *value, void *cb);
1248extern int git_env_bool(const char *, int);
1249extern int git_config_system(void);
1250extern int config_error_nonbool(const char *);
1251#if defined(__GNUC__) && ! defined(__clang__)
1252#define config_error_nonbool(s) (config_error_nonbool(s), -1)
1253#endif
1254extern const char *get_log_output_encoding(void);
1255extern const char *get_commit_output_encoding(void);
1256
1257extern int git_config_parse_parameter(const char *, config_fn_t fn, void *data);
1258
1259struct config_include_data {
1260        int depth;
1261        config_fn_t fn;
1262        void *data;
1263};
1264#define CONFIG_INCLUDE_INIT { 0 }
1265extern int git_config_include(const char *name, const char *value, void *data);
1266
1267/*
1268 * Match and parse a config key of the form:
1269 *
1270 *   section.(subsection.)?key
1271 *
1272 * (i.e., what gets handed to a config_fn_t). The caller provides the section;
1273 * we return -1 if it does not match, 0 otherwise. The subsection and key
1274 * out-parameters are filled by the function (and subsection is NULL if it is
1275 * missing).
1276 */
1277extern int parse_config_key(const char *var,
1278                            const char *section,
1279                            const char **subsection, int *subsection_len,
1280                            const char **key);
1281
1282extern int committer_ident_sufficiently_given(void);
1283extern int author_ident_sufficiently_given(void);
1284
1285extern const char *git_commit_encoding;
1286extern const char *git_log_output_encoding;
1287extern const char *git_mailmap_file;
1288extern const char *git_mailmap_blob;
1289
1290/* IO helper functions */
1291extern void maybe_flush_or_die(FILE *, const char *);
1292extern int copy_fd(int ifd, int ofd);
1293extern int copy_file(const char *dst, const char *src, int mode);
1294extern int copy_file_with_time(const char *dst, const char *src, int mode);
1295extern void write_or_die(int fd, const void *buf, size_t count);
1296extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
1297extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
1298extern void fsync_or_die(int fd, const char *);
1299
1300extern ssize_t read_in_full(int fd, void *buf, size_t count);
1301extern ssize_t write_in_full(int fd, const void *buf, size_t count);
1302static inline ssize_t write_str_in_full(int fd, const char *str)
1303{
1304        return write_in_full(fd, str, strlen(str));
1305}
1306
1307/* pager.c */
1308extern void setup_pager(void);
1309extern const char *pager_program;
1310extern int pager_in_use(void);
1311extern int pager_use_color;
1312extern int term_columns(void);
1313extern int decimal_width(int);
1314extern int check_pager_config(const char *cmd);
1315
1316extern const char *editor_program;
1317extern const char *askpass_program;
1318extern const char *excludes_file;
1319
1320/* base85 */
1321int decode_85(char *dst, const char *line, int linelen);
1322void encode_85(char *buf, const unsigned char *data, int bytes);
1323
1324/* alloc.c */
1325extern void *alloc_blob_node(void);
1326extern void *alloc_tree_node(void);
1327extern void *alloc_commit_node(void);
1328extern void *alloc_tag_node(void);
1329extern void *alloc_object_node(void);
1330extern void alloc_report(void);
1331
1332/* trace.c */
1333__attribute__((format (printf, 1, 2)))
1334extern void trace_printf(const char *format, ...);
1335__attribute__((format (printf, 2, 3)))
1336extern void trace_argv_printf(const char **argv, const char *format, ...);
1337extern void trace_repo_setup(const char *prefix);
1338extern int trace_want(const char *key);
1339__attribute__((format (printf, 2, 3)))
1340extern void trace_printf_key(const char *key, const char *fmt, ...);
1341extern void trace_strbuf(const char *key, const struct strbuf *buf);
1342
1343void packet_trace_identity(const char *prog);
1344
1345/* add */
1346/*
1347 * return 0 if success, 1 - if addition of a file failed and
1348 * ADD_FILES_IGNORE_ERRORS was specified in flags
1349 */
1350int add_files_to_cache(const char *prefix, const struct pathspec *pathspec, int flags);
1351
1352/* diff.c */
1353extern int diff_auto_refresh_index;
1354
1355/* match-trees.c */
1356void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
1357void shift_tree_by(const unsigned char *, const unsigned char *, unsigned char *, const char *);
1358
1359/*
1360 * whitespace rules.
1361 * used by both diff and apply
1362 * last two digits are tab width
1363 */
1364#define WS_BLANK_AT_EOL         0100
1365#define WS_SPACE_BEFORE_TAB     0200
1366#define WS_INDENT_WITH_NON_TAB  0400
1367#define WS_CR_AT_EOL           01000
1368#define WS_BLANK_AT_EOF        02000
1369#define WS_TAB_IN_INDENT       04000
1370#define WS_TRAILING_SPACE      (WS_BLANK_AT_EOL|WS_BLANK_AT_EOF)
1371#define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB|8)
1372#define WS_TAB_WIDTH_MASK        077
1373extern unsigned whitespace_rule_cfg;
1374extern unsigned whitespace_rule(const char *);
1375extern unsigned parse_whitespace_rule(const char *);
1376extern unsigned ws_check(const char *line, int len, unsigned ws_rule);
1377extern void ws_check_emit(const char *line, int len, unsigned ws_rule, FILE *stream, const char *set, const char *reset, const char *ws);
1378extern char *whitespace_error_string(unsigned ws);
1379extern void ws_fix_copy(struct strbuf *, const char *, int, unsigned, int *);
1380extern int ws_blank_line(const char *line, int len, unsigned ws_rule);
1381#define ws_tab_width(rule)     ((rule) & WS_TAB_WIDTH_MASK)
1382
1383/* ls-files */
1384int report_path_error(const char *ps_matched, const struct pathspec *pathspec, const char *prefix);
1385void overlay_tree_on_cache(const char *tree_name, const char *prefix);
1386
1387char *alias_lookup(const char *alias);
1388int split_cmdline(char *cmdline, const char ***argv);
1389/* Takes a negative value returned by split_cmdline */
1390const char *split_cmdline_strerror(int cmdline_errno);
1391
1392/* git.c */
1393struct startup_info {
1394        int have_repository;
1395        const char *prefix;
1396};
1397extern struct startup_info *startup_info;
1398
1399/* merge.c */
1400struct commit_list;
1401int try_merge_command(const char *strategy, size_t xopts_nr,
1402                const char **xopts, struct commit_list *common,
1403                const char *head_arg, struct commit_list *remotes);
1404int checkout_fast_forward(const unsigned char *from,
1405                          const unsigned char *to,
1406                          int overwrite_ignore);
1407
1408
1409int sane_execvp(const char *file, char *const argv[]);
1410
1411/*
1412 * A struct to encapsulate the concept of whether a file has changed
1413 * since we last checked it. This uses criteria similar to those used
1414 * for the index.
1415 */
1416struct stat_validity {
1417        struct stat_data *sd;
1418};
1419
1420void stat_validity_clear(struct stat_validity *sv);
1421
1422/*
1423 * Returns 1 if the path is a regular file (or a symlink to a regular
1424 * file) and matches the saved stat_validity, 0 otherwise.  A missing
1425 * or inaccessible file is considered a match if the struct was just
1426 * initialized, or if the previous update found an inaccessible file.
1427 */
1428int stat_validity_check(struct stat_validity *sv, const char *path);
1429
1430/*
1431 * Update the stat_validity from a file opened at descriptor fd. If
1432 * the file is missing, inaccessible, or not a regular file, then
1433 * future calls to stat_validity_check will match iff one of those
1434 * conditions continues to be true.
1435 */
1436void stat_validity_update(struct stat_validity *sv, int fd);
1437
1438#endif /* CACHE_H */