cache.hon commit treewide: rename 'struct exclude_list' to 'struct pattern_list' (caa3d55)
   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 "list.h"
   8#include "advice.h"
   9#include "gettext.h"
  10#include "convert.h"
  11#include "trace.h"
  12#include "trace2.h"
  13#include "string-list.h"
  14#include "pack-revindex.h"
  15#include "hash.h"
  16#include "path.h"
  17#include "sha1-array.h"
  18#include "repository.h"
  19#include "mem-pool.h"
  20
  21#include <zlib.h>
  22typedef struct git_zstream {
  23        z_stream z;
  24        unsigned long avail_in;
  25        unsigned long avail_out;
  26        unsigned long total_in;
  27        unsigned long total_out;
  28        unsigned char *next_in;
  29        unsigned char *next_out;
  30} git_zstream;
  31
  32void git_inflate_init(git_zstream *);
  33void git_inflate_init_gzip_only(git_zstream *);
  34void git_inflate_end(git_zstream *);
  35int git_inflate(git_zstream *, int flush);
  36
  37void git_deflate_init(git_zstream *, int level);
  38void git_deflate_init_gzip(git_zstream *, int level);
  39void git_deflate_init_raw(git_zstream *, int level);
  40void git_deflate_end(git_zstream *);
  41int git_deflate_abort(git_zstream *);
  42int git_deflate_end_gently(git_zstream *);
  43int git_deflate(git_zstream *, int flush);
  44unsigned long git_deflate_bound(git_zstream *, unsigned long);
  45
  46/* The length in bytes and in hex digits of an object name (SHA-1 value). */
  47#define GIT_SHA1_RAWSZ 20
  48#define GIT_SHA1_HEXSZ (2 * GIT_SHA1_RAWSZ)
  49/* The block size of SHA-1. */
  50#define GIT_SHA1_BLKSZ 64
  51
  52/* The length in bytes and in hex digits of an object name (SHA-256 value). */
  53#define GIT_SHA256_RAWSZ 32
  54#define GIT_SHA256_HEXSZ (2 * GIT_SHA256_RAWSZ)
  55/* The block size of SHA-256. */
  56#define GIT_SHA256_BLKSZ 64
  57
  58/* The length in byte and in hex digits of the largest possible hash value. */
  59#define GIT_MAX_RAWSZ GIT_SHA256_RAWSZ
  60#define GIT_MAX_HEXSZ GIT_SHA256_HEXSZ
  61/* The largest possible block size for any supported hash. */
  62#define GIT_MAX_BLKSZ GIT_SHA256_BLKSZ
  63
  64struct object_id {
  65        unsigned char hash[GIT_MAX_RAWSZ];
  66};
  67
  68#define the_hash_algo the_repository->hash_algo
  69
  70#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
  71#define DTYPE(de)       ((de)->d_type)
  72#else
  73#undef DT_UNKNOWN
  74#undef DT_DIR
  75#undef DT_REG
  76#undef DT_LNK
  77#define DT_UNKNOWN      0
  78#define DT_DIR          1
  79#define DT_REG          2
  80#define DT_LNK          3
  81#define DTYPE(de)       DT_UNKNOWN
  82#endif
  83
  84/* unknown mode (impossible combination S_IFIFO|S_IFCHR) */
  85#define S_IFINVALID     0030000
  86
  87/*
  88 * A "directory link" is a link to another git directory.
  89 *
  90 * The value 0160000 is not normally a valid mode, and
  91 * also just happens to be S_IFDIR + S_IFLNK
  92 */
  93#define S_IFGITLINK     0160000
  94#define S_ISGITLINK(m)  (((m) & S_IFMT) == S_IFGITLINK)
  95
  96/*
  97 * Some mode bits are also used internally for computations.
  98 *
  99 * They *must* not overlap with any valid modes, and they *must* not be emitted
 100 * to outside world - i.e. appear on disk or network. In other words, it's just
 101 * temporary fields, which we internally use, but they have to stay in-house.
 102 *
 103 * ( such approach is valid, as standard S_IF* fits into 16 bits, and in Git
 104 *   codebase mode is `unsigned int` which is assumed to be at least 32 bits )
 105 */
 106
 107/* used internally in tree-diff */
 108#define S_DIFFTREE_IFXMIN_NEQ   0x80000000
 109
 110
 111/*
 112 * Intensive research over the course of many years has shown that
 113 * port 9418 is totally unused by anything else. Or
 114 *
 115 *      Your search - "port 9418" - did not match any documents.
 116 *
 117 * as www.google.com puts it.
 118 *
 119 * This port has been properly assigned for git use by IANA:
 120 * git (Assigned-9418) [I06-050728-0001].
 121 *
 122 *      git  9418/tcp   git pack transfer service
 123 *      git  9418/udp   git pack transfer service
 124 *
 125 * with Linus Torvalds <torvalds@osdl.org> as the point of
 126 * contact. September 2005.
 127 *
 128 * See http://www.iana.org/assignments/port-numbers
 129 */
 130#define DEFAULT_GIT_PORT 9418
 131
 132/*
 133 * Basic data structures for the directory cache
 134 */
 135
 136#define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
 137struct cache_header {
 138        uint32_t hdr_signature;
 139        uint32_t hdr_version;
 140        uint32_t hdr_entries;
 141};
 142
 143#define INDEX_FORMAT_LB 2
 144#define INDEX_FORMAT_UB 4
 145
 146/*
 147 * The "cache_time" is just the low 32 bits of the
 148 * time. It doesn't matter if it overflows - we only
 149 * check it for equality in the 32 bits we save.
 150 */
 151struct cache_time {
 152        uint32_t sec;
 153        uint32_t nsec;
 154};
 155
 156struct stat_data {
 157        struct cache_time sd_ctime;
 158        struct cache_time sd_mtime;
 159        unsigned int sd_dev;
 160        unsigned int sd_ino;
 161        unsigned int sd_uid;
 162        unsigned int sd_gid;
 163        unsigned int sd_size;
 164};
 165
 166struct cache_entry {
 167        struct hashmap_entry ent;
 168        struct stat_data ce_stat_data;
 169        unsigned int ce_mode;
 170        unsigned int ce_flags;
 171        unsigned int mem_pool_allocated;
 172        unsigned int ce_namelen;
 173        unsigned int index;     /* for link extension */
 174        struct object_id oid;
 175        char name[FLEX_ARRAY]; /* more */
 176};
 177
 178#define CE_STAGEMASK (0x3000)
 179#define CE_EXTENDED  (0x4000)
 180#define CE_VALID     (0x8000)
 181#define CE_STAGESHIFT 12
 182
 183/*
 184 * Range 0xFFFF0FFF in ce_flags is divided into
 185 * two parts: in-memory flags and on-disk ones.
 186 * Flags in CE_EXTENDED_FLAGS will get saved on-disk
 187 * if you want to save a new flag, add it in
 188 * CE_EXTENDED_FLAGS
 189 *
 190 * In-memory only flags
 191 */
 192#define CE_UPDATE            (1 << 16)
 193#define CE_REMOVE            (1 << 17)
 194#define CE_UPTODATE          (1 << 18)
 195#define CE_ADDED             (1 << 19)
 196
 197#define CE_HASHED            (1 << 20)
 198#define CE_FSMONITOR_VALID   (1 << 21)
 199#define CE_WT_REMOVE         (1 << 22) /* remove in work directory */
 200#define CE_CONFLICTED        (1 << 23)
 201
 202#define CE_UNPACKED          (1 << 24)
 203#define CE_NEW_SKIP_WORKTREE (1 << 25)
 204
 205/* used to temporarily mark paths matched by pathspecs */
 206#define CE_MATCHED           (1 << 26)
 207
 208#define CE_UPDATE_IN_BASE    (1 << 27)
 209#define CE_STRIP_NAME        (1 << 28)
 210
 211/*
 212 * Extended on-disk flags
 213 */
 214#define CE_INTENT_TO_ADD     (1 << 29)
 215#define CE_SKIP_WORKTREE     (1 << 30)
 216/* CE_EXTENDED2 is for future extension */
 217#define CE_EXTENDED2         (1U << 31)
 218
 219#define CE_EXTENDED_FLAGS (CE_INTENT_TO_ADD | CE_SKIP_WORKTREE)
 220
 221/*
 222 * Safeguard to avoid saving wrong flags:
 223 *  - CE_EXTENDED2 won't get saved until its semantic is known
 224 *  - Bits in 0x0000FFFF have been saved in ce_flags already
 225 *  - Bits in 0x003F0000 are currently in-memory flags
 226 */
 227#if CE_EXTENDED_FLAGS & 0x803FFFFF
 228#error "CE_EXTENDED_FLAGS out of range"
 229#endif
 230
 231/* Forward structure decls */
 232struct pathspec;
 233struct child_process;
 234struct tree;
 235
 236/*
 237 * Copy the sha1 and stat state of a cache entry from one to
 238 * another. But we never change the name, or the hash state!
 239 */
 240static inline void copy_cache_entry(struct cache_entry *dst,
 241                                    const struct cache_entry *src)
 242{
 243        unsigned int state = dst->ce_flags & CE_HASHED;
 244        int mem_pool_allocated = dst->mem_pool_allocated;
 245
 246        /* Don't copy hash chain and name */
 247        memcpy(&dst->ce_stat_data, &src->ce_stat_data,
 248                        offsetof(struct cache_entry, name) -
 249                        offsetof(struct cache_entry, ce_stat_data));
 250
 251        /* Restore the hash state */
 252        dst->ce_flags = (dst->ce_flags & ~CE_HASHED) | state;
 253
 254        /* Restore the mem_pool_allocated flag */
 255        dst->mem_pool_allocated = mem_pool_allocated;
 256}
 257
 258static inline unsigned create_ce_flags(unsigned stage)
 259{
 260        return (stage << CE_STAGESHIFT);
 261}
 262
 263#define ce_namelen(ce) ((ce)->ce_namelen)
 264#define ce_size(ce) cache_entry_size(ce_namelen(ce))
 265#define ce_stage(ce) ((CE_STAGEMASK & (ce)->ce_flags) >> CE_STAGESHIFT)
 266#define ce_uptodate(ce) ((ce)->ce_flags & CE_UPTODATE)
 267#define ce_skip_worktree(ce) ((ce)->ce_flags & CE_SKIP_WORKTREE)
 268#define ce_mark_uptodate(ce) ((ce)->ce_flags |= CE_UPTODATE)
 269#define ce_intent_to_add(ce) ((ce)->ce_flags & CE_INTENT_TO_ADD)
 270
 271#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 272static inline unsigned int create_ce_mode(unsigned int mode)
 273{
 274        if (S_ISLNK(mode))
 275                return S_IFLNK;
 276        if (S_ISDIR(mode) || S_ISGITLINK(mode))
 277                return S_IFGITLINK;
 278        return S_IFREG | ce_permissions(mode);
 279}
 280static inline unsigned int ce_mode_from_stat(const struct cache_entry *ce,
 281                                             unsigned int mode)
 282{
 283        extern int trust_executable_bit, has_symlinks;
 284        if (!has_symlinks && S_ISREG(mode) &&
 285            ce && S_ISLNK(ce->ce_mode))
 286                return ce->ce_mode;
 287        if (!trust_executable_bit && S_ISREG(mode)) {
 288                if (ce && S_ISREG(ce->ce_mode))
 289                        return ce->ce_mode;
 290                return create_ce_mode(0666);
 291        }
 292        return create_ce_mode(mode);
 293}
 294static inline int ce_to_dtype(const struct cache_entry *ce)
 295{
 296        unsigned ce_mode = ntohl(ce->ce_mode);
 297        if (S_ISREG(ce_mode))
 298                return DT_REG;
 299        else if (S_ISDIR(ce_mode) || S_ISGITLINK(ce_mode))
 300                return DT_DIR;
 301        else if (S_ISLNK(ce_mode))
 302                return DT_LNK;
 303        else
 304                return DT_UNKNOWN;
 305}
 306static inline unsigned int canon_mode(unsigned int mode)
 307{
 308        if (S_ISREG(mode))
 309                return S_IFREG | ce_permissions(mode);
 310        if (S_ISLNK(mode))
 311                return S_IFLNK;
 312        if (S_ISDIR(mode))
 313                return S_IFDIR;
 314        return S_IFGITLINK;
 315}
 316
 317#define cache_entry_size(len) (offsetof(struct cache_entry,name) + (len) + 1)
 318
 319#define SOMETHING_CHANGED       (1 << 0) /* unclassified changes go here */
 320#define CE_ENTRY_CHANGED        (1 << 1)
 321#define CE_ENTRY_REMOVED        (1 << 2)
 322#define CE_ENTRY_ADDED          (1 << 3)
 323#define RESOLVE_UNDO_CHANGED    (1 << 4)
 324#define CACHE_TREE_CHANGED      (1 << 5)
 325#define SPLIT_INDEX_ORDERED     (1 << 6)
 326#define UNTRACKED_CHANGED       (1 << 7)
 327#define FSMONITOR_CHANGED       (1 << 8)
 328
 329struct split_index;
 330struct untracked_cache;
 331
 332struct index_state {
 333        struct cache_entry **cache;
 334        unsigned int version;
 335        unsigned int cache_nr, cache_alloc, cache_changed;
 336        struct string_list *resolve_undo;
 337        struct cache_tree *cache_tree;
 338        struct split_index *split_index;
 339        struct cache_time timestamp;
 340        unsigned name_hash_initialized : 1,
 341                 initialized : 1,
 342                 drop_cache_tree : 1,
 343                 updated_workdir : 1,
 344                 updated_skipworktree : 1,
 345                 fsmonitor_has_run_once : 1;
 346        struct hashmap name_hash;
 347        struct hashmap dir_hash;
 348        struct object_id oid;
 349        struct untracked_cache *untracked;
 350        uint64_t fsmonitor_last_update;
 351        struct ewah_bitmap *fsmonitor_dirty;
 352        struct mem_pool *ce_mem_pool;
 353};
 354
 355/* Name hashing */
 356int test_lazy_init_name_hash(struct index_state *istate, int try_threaded);
 357void add_name_hash(struct index_state *istate, struct cache_entry *ce);
 358void remove_name_hash(struct index_state *istate, struct cache_entry *ce);
 359void free_name_hash(struct index_state *istate);
 360
 361
 362/* Cache entry creation and cleanup */
 363
 364/*
 365 * Create cache_entry intended for use in the specified index. Caller
 366 * is responsible for discarding the cache_entry with
 367 * `discard_cache_entry`.
 368 */
 369struct cache_entry *make_cache_entry(struct index_state *istate,
 370                                     unsigned int mode,
 371                                     const struct object_id *oid,
 372                                     const char *path,
 373                                     int stage,
 374                                     unsigned int refresh_options);
 375
 376struct cache_entry *make_empty_cache_entry(struct index_state *istate,
 377                                           size_t name_len);
 378
 379/*
 380 * Create a cache_entry that is not intended to be added to an index.
 381 * Caller is responsible for discarding the cache_entry
 382 * with `discard_cache_entry`.
 383 */
 384struct cache_entry *make_transient_cache_entry(unsigned int mode,
 385                                               const struct object_id *oid,
 386                                               const char *path,
 387                                               int stage);
 388
 389struct cache_entry *make_empty_transient_cache_entry(size_t name_len);
 390
 391/*
 392 * Discard cache entry.
 393 */
 394void discard_cache_entry(struct cache_entry *ce);
 395
 396/*
 397 * Check configuration if we should perform extra validation on cache
 398 * entries.
 399 */
 400int should_validate_cache_entries(void);
 401
 402/*
 403 * Duplicate a cache_entry. Allocate memory for the new entry from a
 404 * memory_pool. Takes into account cache_entry fields that are meant
 405 * for managing the underlying memory allocation of the cache_entry.
 406 */
 407struct cache_entry *dup_cache_entry(const struct cache_entry *ce, struct index_state *istate);
 408
 409/*
 410 * Validate the cache entries in the index.  This is an internal
 411 * consistency check that the cache_entry structs are allocated from
 412 * the expected memory pool.
 413 */
 414void validate_cache_entries(const struct index_state *istate);
 415
 416#ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
 417extern struct index_state the_index;
 418
 419#define active_cache (the_index.cache)
 420#define active_nr (the_index.cache_nr)
 421#define active_alloc (the_index.cache_alloc)
 422#define active_cache_changed (the_index.cache_changed)
 423#define active_cache_tree (the_index.cache_tree)
 424
 425#define read_cache() repo_read_index(the_repository)
 426#define read_cache_from(path) read_index_from(&the_index, (path), (get_git_dir()))
 427#define read_cache_preload(pathspec) repo_read_index_preload(the_repository, (pathspec), 0)
 428#define is_cache_unborn() is_index_unborn(&the_index)
 429#define read_cache_unmerged() repo_read_index_unmerged(the_repository)
 430#define discard_cache() discard_index(&the_index)
 431#define unmerged_cache() unmerged_index(&the_index)
 432#define cache_name_pos(name, namelen) index_name_pos(&the_index,(name),(namelen))
 433#define add_cache_entry(ce, option) add_index_entry(&the_index, (ce), (option))
 434#define rename_cache_entry_at(pos, new_name) rename_index_entry_at(&the_index, (pos), (new_name))
 435#define remove_cache_entry_at(pos) remove_index_entry_at(&the_index, (pos))
 436#define remove_file_from_cache(path) remove_file_from_index(&the_index, (path))
 437#define add_to_cache(path, st, flags) add_to_index(&the_index, (path), (st), (flags))
 438#define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags))
 439#define chmod_cache_entry(ce, flip) chmod_index_entry(&the_index, (ce), (flip))
 440#define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
 441#define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
 442#define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
 443#define cache_dir_exists(name, namelen) index_dir_exists(&the_index, (name), (namelen))
 444#define cache_file_exists(name, namelen, igncase) index_file_exists(&the_index, (name), (namelen), (igncase))
 445#define cache_name_is_other(name, namelen) index_name_is_other(&the_index, (name), (namelen))
 446#define resolve_undo_clear() resolve_undo_clear_index(&the_index)
 447#define unmerge_cache_entry_at(at) unmerge_index_entry_at(&the_index, at)
 448#define unmerge_cache(pathspec) unmerge_index(&the_index, pathspec)
 449#define read_blob_data_from_cache(path, sz) read_blob_data_from_index(&the_index, (path), (sz))
 450#define hold_locked_index(lock_file, flags) repo_hold_locked_index(the_repository, (lock_file), (flags))
 451#endif
 452
 453#define TYPE_BITS 3
 454
 455/*
 456 * Values in this enum (except those outside the 3 bit range) are part
 457 * of pack file format. See Documentation/technical/pack-format.txt
 458 * for more information.
 459 */
 460enum object_type {
 461        OBJ_BAD = -1,
 462        OBJ_NONE = 0,
 463        OBJ_COMMIT = 1,
 464        OBJ_TREE = 2,
 465        OBJ_BLOB = 3,
 466        OBJ_TAG = 4,
 467        /* 5 for future expansion */
 468        OBJ_OFS_DELTA = 6,
 469        OBJ_REF_DELTA = 7,
 470        OBJ_ANY,
 471        OBJ_MAX
 472};
 473
 474static inline enum object_type object_type(unsigned int mode)
 475{
 476        return S_ISDIR(mode) ? OBJ_TREE :
 477                S_ISGITLINK(mode) ? OBJ_COMMIT :
 478                OBJ_BLOB;
 479}
 480
 481/* Double-check local_repo_env below if you add to this list. */
 482#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 483#define GIT_COMMON_DIR_ENVIRONMENT "GIT_COMMON_DIR"
 484#define GIT_NAMESPACE_ENVIRONMENT "GIT_NAMESPACE"
 485#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
 486#define GIT_PREFIX_ENVIRONMENT "GIT_PREFIX"
 487#define GIT_SUPER_PREFIX_ENVIRONMENT "GIT_INTERNAL_SUPER_PREFIX"
 488#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 489#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 490#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 491#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 492#define GIT_SHALLOW_FILE_ENVIRONMENT "GIT_SHALLOW_FILE"
 493#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
 494#define CONFIG_ENVIRONMENT "GIT_CONFIG"
 495#define CONFIG_DATA_ENVIRONMENT "GIT_CONFIG_PARAMETERS"
 496#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 497#define CEILING_DIRECTORIES_ENVIRONMENT "GIT_CEILING_DIRECTORIES"
 498#define NO_REPLACE_OBJECTS_ENVIRONMENT "GIT_NO_REPLACE_OBJECTS"
 499#define GIT_REPLACE_REF_BASE_ENVIRONMENT "GIT_REPLACE_REF_BASE"
 500#define GITATTRIBUTES_FILE ".gitattributes"
 501#define INFOATTRIBUTES_FILE "info/attributes"
 502#define ATTRIBUTE_MACRO_PREFIX "[attr]"
 503#define GITMODULES_FILE ".gitmodules"
 504#define GITMODULES_INDEX ":.gitmodules"
 505#define GITMODULES_HEAD "HEAD:.gitmodules"
 506#define GIT_NOTES_REF_ENVIRONMENT "GIT_NOTES_REF"
 507#define GIT_NOTES_DEFAULT_REF "refs/notes/commits"
 508#define GIT_NOTES_DISPLAY_REF_ENVIRONMENT "GIT_NOTES_DISPLAY_REF"
 509#define GIT_NOTES_REWRITE_REF_ENVIRONMENT "GIT_NOTES_REWRITE_REF"
 510#define GIT_NOTES_REWRITE_MODE_ENVIRONMENT "GIT_NOTES_REWRITE_MODE"
 511#define GIT_LITERAL_PATHSPECS_ENVIRONMENT "GIT_LITERAL_PATHSPECS"
 512#define GIT_GLOB_PATHSPECS_ENVIRONMENT "GIT_GLOB_PATHSPECS"
 513#define GIT_NOGLOB_PATHSPECS_ENVIRONMENT "GIT_NOGLOB_PATHSPECS"
 514#define GIT_ICASE_PATHSPECS_ENVIRONMENT "GIT_ICASE_PATHSPECS"
 515#define GIT_QUARANTINE_ENVIRONMENT "GIT_QUARANTINE_PATH"
 516#define GIT_OPTIONAL_LOCKS_ENVIRONMENT "GIT_OPTIONAL_LOCKS"
 517#define GIT_TEXT_DOMAIN_DIR_ENVIRONMENT "GIT_TEXTDOMAINDIR"
 518
 519/*
 520 * Environment variable used in handshaking the wire protocol.
 521 * Contains a colon ':' separated list of keys with optional values
 522 * 'key[=value]'.  Presence of unknown keys and values must be
 523 * ignored.
 524 */
 525#define GIT_PROTOCOL_ENVIRONMENT "GIT_PROTOCOL"
 526/* HTTP header used to handshake the wire protocol */
 527#define GIT_PROTOCOL_HEADER "Git-Protocol"
 528
 529/*
 530 * This environment variable is expected to contain a boolean indicating
 531 * whether we should or should not treat:
 532 *
 533 *   GIT_DIR=foo.git git ...
 534 *
 535 * as if GIT_WORK_TREE=. was given. It's not expected that users will make use
 536 * of this, but we use it internally to communicate to sub-processes that we
 537 * are in a bare repo. If not set, defaults to true.
 538 */
 539#define GIT_IMPLICIT_WORK_TREE_ENVIRONMENT "GIT_IMPLICIT_WORK_TREE"
 540
 541/*
 542 * Repository-local GIT_* environment variables; these will be cleared
 543 * when git spawns a sub-process that runs inside another repository.
 544 * The array is NULL-terminated, which makes it easy to pass in the "env"
 545 * parameter of a run-command invocation, or to do a simple walk.
 546 */
 547extern const char * const local_repo_env[];
 548
 549void setup_git_env(const char *git_dir);
 550
 551/*
 552 * Returns true iff we have a configured git repository (either via
 553 * setup_git_directory, or in the environment via $GIT_DIR).
 554 */
 555int have_git_dir(void);
 556
 557extern int is_bare_repository_cfg;
 558int is_bare_repository(void);
 559int is_inside_git_dir(void);
 560extern char *git_work_tree_cfg;
 561int is_inside_work_tree(void);
 562const char *get_git_dir(void);
 563const char *get_git_common_dir(void);
 564char *get_object_directory(void);
 565char *get_index_file(void);
 566char *get_graft_file(struct repository *r);
 567void set_git_dir(const char *path);
 568int get_common_dir_noenv(struct strbuf *sb, const char *gitdir);
 569int get_common_dir(struct strbuf *sb, const char *gitdir);
 570const char *get_git_namespace(void);
 571const char *strip_namespace(const char *namespaced_ref);
 572const char *get_super_prefix(void);
 573const char *get_git_work_tree(void);
 574
 575/*
 576 * Return true if the given path is a git directory; note that this _just_
 577 * looks at the directory itself. If you want to know whether "foo/.git"
 578 * is a repository, you must feed that path, not just "foo".
 579 */
 580int is_git_directory(const char *path);
 581
 582/*
 583 * Return 1 if the given path is the root of a git repository or
 584 * submodule, else 0. Will not return 1 for bare repositories with the
 585 * exception of creating a bare repository in "foo/.git" and calling
 586 * is_git_repository("foo").
 587 *
 588 * If we run into read errors, we err on the side of saying "yes, it is",
 589 * as we usually consider sub-repos precious, and would prefer to err on the
 590 * side of not disrupting or deleting them.
 591 */
 592int is_nonbare_repository_dir(struct strbuf *path);
 593
 594#define READ_GITFILE_ERR_STAT_FAILED 1
 595#define READ_GITFILE_ERR_NOT_A_FILE 2
 596#define READ_GITFILE_ERR_OPEN_FAILED 3
 597#define READ_GITFILE_ERR_READ_FAILED 4
 598#define READ_GITFILE_ERR_INVALID_FORMAT 5
 599#define READ_GITFILE_ERR_NO_PATH 6
 600#define READ_GITFILE_ERR_NOT_A_REPO 7
 601#define READ_GITFILE_ERR_TOO_LARGE 8
 602void read_gitfile_error_die(int error_code, const char *path, const char *dir);
 603const char *read_gitfile_gently(const char *path, int *return_error_code);
 604#define read_gitfile(path) read_gitfile_gently((path), NULL)
 605const char *resolve_gitdir_gently(const char *suspect, int *return_error_code);
 606#define resolve_gitdir(path) resolve_gitdir_gently((path), NULL)
 607
 608void set_git_work_tree(const char *tree);
 609
 610#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 611
 612void setup_work_tree(void);
 613/*
 614 * Find the commondir and gitdir of the repository that contains the current
 615 * working directory, without changing the working directory or other global
 616 * state. The result is appended to commondir and gitdir.  If the discovered
 617 * gitdir does not correspond to a worktree, then 'commondir' and 'gitdir' will
 618 * both have the same result appended to the buffer.  The return value is
 619 * either 0 upon success and non-zero if no repository was found.
 620 */
 621int discover_git_directory(struct strbuf *commondir,
 622                           struct strbuf *gitdir);
 623const char *setup_git_directory_gently(int *);
 624const char *setup_git_directory(void);
 625char *prefix_path(const char *prefix, int len, const char *path);
 626char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
 627
 628/*
 629 * Concatenate "prefix" (if len is non-zero) and "path", with no
 630 * connecting characters (so "prefix" should end with a "/").
 631 * Unlike prefix_path, this should be used if the named file does
 632 * not have to interact with index entry; i.e. name of a random file
 633 * on the filesystem.
 634 *
 635 * The return value is always a newly allocated string (even if the
 636 * prefix was empty).
 637 */
 638char *prefix_filename(const char *prefix, const char *path);
 639
 640int check_filename(const char *prefix, const char *name);
 641void verify_filename(const char *prefix,
 642                     const char *name,
 643                     int diagnose_misspelt_rev);
 644void verify_non_filename(const char *prefix, const char *name);
 645int path_inside_repo(const char *prefix, const char *path);
 646
 647#define INIT_DB_QUIET 0x0001
 648#define INIT_DB_EXIST_OK 0x0002
 649
 650int init_db(const char *git_dir, const char *real_git_dir,
 651            const char *template_dir, unsigned int flags);
 652
 653void sanitize_stdfds(void);
 654int daemonize(void);
 655
 656#define alloc_nr(x) (((x)+16)*3/2)
 657
 658/*
 659 * Realloc the buffer pointed at by variable 'x' so that it can hold
 660 * at least 'nr' entries; the number of entries currently allocated
 661 * is 'alloc', using the standard growing factor alloc_nr() macro.
 662 *
 663 * Consider using ALLOC_GROW_BY instead of ALLOC_GROW as it has some
 664 * added niceties.
 665 *
 666 * DO NOT USE any expression with side-effect for 'x', 'nr', or 'alloc'.
 667 */
 668#define ALLOC_GROW(x, nr, alloc) \
 669        do { \
 670                if ((nr) > alloc) { \
 671                        if (alloc_nr(alloc) < (nr)) \
 672                                alloc = (nr); \
 673                        else \
 674                                alloc = alloc_nr(alloc); \
 675                        REALLOC_ARRAY(x, alloc); \
 676                } \
 677        } while (0)
 678
 679/*
 680 * Similar to ALLOC_GROW but handles updating of the nr value and
 681 * zeroing the bytes of the newly-grown array elements.
 682 *
 683 * DO NOT USE any expression with side-effect for any of the
 684 * arguments.
 685 */
 686#define ALLOC_GROW_BY(x, nr, increase, alloc) \
 687        do { \
 688                if (increase) { \
 689                        size_t new_nr = nr + (increase); \
 690                        if (new_nr < nr) \
 691                                BUG("negative growth in ALLOC_GROW_BY"); \
 692                        ALLOC_GROW(x, new_nr, alloc); \
 693                        memset((x) + nr, 0, sizeof(*(x)) * (increase)); \
 694                        nr = new_nr; \
 695                } \
 696        } while (0)
 697
 698/* Initialize and use the cache information */
 699struct lock_file;
 700void preload_index(struct index_state *index,
 701                   const struct pathspec *pathspec,
 702                   unsigned int refresh_flags);
 703int do_read_index(struct index_state *istate, const char *path,
 704                  int must_exist); /* for testting only! */
 705int read_index_from(struct index_state *, const char *path,
 706                    const char *gitdir);
 707int is_index_unborn(struct index_state *);
 708
 709/* For use with `write_locked_index()`. */
 710#define COMMIT_LOCK             (1 << 0)
 711#define SKIP_IF_UNCHANGED       (1 << 1)
 712
 713/*
 714 * Write the index while holding an already-taken lock. Close the lock,
 715 * and if `COMMIT_LOCK` is given, commit it.
 716 *
 717 * Unless a split index is in use, write the index into the lockfile.
 718 *
 719 * With a split index, write the shared index to a temporary file,
 720 * adjust its permissions and rename it into place, then write the
 721 * split index to the lockfile. If the temporary file for the shared
 722 * index cannot be created, fall back to the behavior described in
 723 * the previous paragraph.
 724 *
 725 * With `COMMIT_LOCK`, the lock is always committed or rolled back.
 726 * Without it, the lock is closed, but neither committed nor rolled
 727 * back.
 728 *
 729 * If `SKIP_IF_UNCHANGED` is given and the index is unchanged, nothing
 730 * is written (and the lock is rolled back if `COMMIT_LOCK` is given).
 731 */
 732int write_locked_index(struct index_state *, struct lock_file *lock, unsigned flags);
 733
 734int discard_index(struct index_state *);
 735void move_index_extensions(struct index_state *dst, struct index_state *src);
 736int unmerged_index(const struct index_state *);
 737
 738/**
 739 * Returns 1 if istate differs from tree, 0 otherwise.  If tree is NULL,
 740 * compares istate to HEAD.  If tree is NULL and on an unborn branch,
 741 * returns 1 if there are entries in istate, 0 otherwise.  If an strbuf is
 742 * provided, the space-separated list of files that differ will be appended
 743 * to it.
 744 */
 745int repo_index_has_changes(struct repository *repo,
 746                           struct tree *tree,
 747                           struct strbuf *sb);
 748
 749int verify_path(const char *path, unsigned mode);
 750int strcmp_offset(const char *s1, const char *s2, size_t *first_change);
 751int index_dir_exists(struct index_state *istate, const char *name, int namelen);
 752void adjust_dirname_case(struct index_state *istate, char *name);
 753struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 754
 755/*
 756 * Searches for an entry defined by name and namelen in the given index.
 757 * If the return value is positive (including 0) it is the position of an
 758 * exact match. If the return value is negative, the negated value minus 1
 759 * is the position where the entry would be inserted.
 760 * Example: The current index consists of these files and its stages:
 761 *
 762 *   b#0, d#0, f#1, f#3
 763 *
 764 * index_name_pos(&index, "a", 1) -> -1
 765 * index_name_pos(&index, "b", 1) ->  0
 766 * index_name_pos(&index, "c", 1) -> -2
 767 * index_name_pos(&index, "d", 1) ->  1
 768 * index_name_pos(&index, "e", 1) -> -3
 769 * index_name_pos(&index, "f", 1) -> -3
 770 * index_name_pos(&index, "g", 1) -> -5
 771 */
 772int index_name_pos(const struct index_state *, const char *name, int namelen);
 773
 774#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 775#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 776#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 777#define ADD_CACHE_JUST_APPEND 8         /* Append only; tree.c::read_tree() */
 778#define ADD_CACHE_NEW_ONLY 16           /* Do not replace existing ones */
 779#define ADD_CACHE_KEEP_CACHE_TREE 32    /* Do not invalidate cache-tree */
 780#define ADD_CACHE_RENORMALIZE 64        /* Pass along HASH_RENORMALIZE */
 781int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
 782void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
 783
 784/* Remove entry, return true if there are more entries to go. */
 785int remove_index_entry_at(struct index_state *, int pos);
 786
 787void remove_marked_cache_entries(struct index_state *istate, int invalidate);
 788int remove_file_from_index(struct index_state *, const char *path);
 789#define ADD_CACHE_VERBOSE 1
 790#define ADD_CACHE_PRETEND 2
 791#define ADD_CACHE_IGNORE_ERRORS 4
 792#define ADD_CACHE_IGNORE_REMOVAL 8
 793#define ADD_CACHE_INTENT 16
 794/*
 795 * These two are used to add the contents of the file at path
 796 * to the index, marking the working tree up-to-date by storing
 797 * the cached stat info in the resulting cache entry.  A caller
 798 * that has already run lstat(2) on the path can call
 799 * add_to_index(), and all others can call add_file_to_index();
 800 * the latter will do necessary lstat(2) internally before
 801 * calling the former.
 802 */
 803int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
 804int add_file_to_index(struct index_state *, const char *path, int flags);
 805
 806int chmod_index_entry(struct index_state *, struct cache_entry *ce, char flip);
 807int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
 808void set_object_name_for_intent_to_add_entry(struct cache_entry *ce);
 809int index_name_is_other(const struct index_state *, const char *, int);
 810void *read_blob_data_from_index(const struct index_state *, const char *, unsigned long *);
 811
 812/* do stat comparison even if CE_VALID is true */
 813#define CE_MATCH_IGNORE_VALID           01
 814/* do not check the contents but report dirty on racily-clean entries */
 815#define CE_MATCH_RACY_IS_DIRTY          02
 816/* do stat comparison even if CE_SKIP_WORKTREE is true */
 817#define CE_MATCH_IGNORE_SKIP_WORKTREE   04
 818/* ignore non-existent files during stat update  */
 819#define CE_MATCH_IGNORE_MISSING         0x08
 820/* enable stat refresh */
 821#define CE_MATCH_REFRESH                0x10
 822/* don't refresh_fsmonitor state or do stat comparison even if CE_FSMONITOR_VALID is true */
 823#define CE_MATCH_IGNORE_FSMONITOR 0X20
 824int is_racy_timestamp(const struct index_state *istate,
 825                      const struct cache_entry *ce);
 826int ie_match_stat(struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 827int ie_modified(struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 828
 829#define HASH_WRITE_OBJECT 1
 830#define HASH_FORMAT_CHECK 2
 831#define HASH_RENORMALIZE  4
 832int index_fd(struct index_state *istate, struct object_id *oid, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
 833int index_path(struct index_state *istate, struct object_id *oid, const char *path, struct stat *st, unsigned flags);
 834
 835/*
 836 * Record to sd the data from st that we use to check whether a file
 837 * might have changed.
 838 */
 839void fill_stat_data(struct stat_data *sd, struct stat *st);
 840
 841/*
 842 * Return 0 if st is consistent with a file not having been changed
 843 * since sd was filled.  If there are differences, return a
 844 * combination of MTIME_CHANGED, CTIME_CHANGED, OWNER_CHANGED,
 845 * INODE_CHANGED, and DATA_CHANGED.
 846 */
 847int match_stat_data(const struct stat_data *sd, struct stat *st);
 848int match_stat_data_racy(const struct index_state *istate,
 849                         const struct stat_data *sd, struct stat *st);
 850
 851void fill_stat_cache_info(struct index_state *istate, struct cache_entry *ce, struct stat *st);
 852
 853#define REFRESH_REALLY          0x0001  /* ignore_valid */
 854#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 855#define REFRESH_QUIET           0x0004  /* be quiet about it */
 856#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 857#define REFRESH_IGNORE_SUBMODULES       0x0010  /* ignore submodules */
 858#define REFRESH_IN_PORCELAIN    0x0020  /* user friendly output, not "needs update" */
 859#define REFRESH_PROGRESS        0x0040  /* show progress bar if stderr is tty */
 860int refresh_index(struct index_state *, unsigned int flags, const struct pathspec *pathspec, char *seen, const char *header_msg);
 861struct cache_entry *refresh_cache_entry(struct index_state *, struct cache_entry *, unsigned int);
 862
 863void set_alternate_index_output(const char *);
 864
 865extern int verify_index_checksum;
 866extern int verify_ce_order;
 867
 868/* Environment bits from configuration mechanism */
 869extern int trust_executable_bit;
 870extern int trust_ctime;
 871extern int check_stat;
 872extern int quote_path_fully;
 873extern int has_symlinks;
 874extern int minimum_abbrev, default_abbrev;
 875extern int ignore_case;
 876extern int assume_unchanged;
 877extern int prefer_symlink_refs;
 878extern int warn_ambiguous_refs;
 879extern int warn_on_object_refname_ambiguity;
 880extern const char *apply_default_whitespace;
 881extern const char *apply_default_ignorewhitespace;
 882extern const char *git_attributes_file;
 883extern const char *git_hooks_path;
 884extern int zlib_compression_level;
 885extern int core_compression_level;
 886extern int pack_compression_level;
 887extern size_t packed_git_window_size;
 888extern size_t packed_git_limit;
 889extern size_t delta_base_cache_limit;
 890extern unsigned long big_file_threshold;
 891extern unsigned long pack_size_limit_cfg;
 892
 893/*
 894 * Accessors for the core.sharedrepository config which lazy-load the value
 895 * from the config (if not already set). The "reset" function can be
 896 * used to unset "set" or cached value, meaning that the value will be loaded
 897 * fresh from the config file on the next call to get_shared_repository().
 898 */
 899void set_shared_repository(int value);
 900int get_shared_repository(void);
 901void reset_shared_repository(void);
 902
 903/*
 904 * Do replace refs need to be checked this run?  This variable is
 905 * initialized to true unless --no-replace-object is used or
 906 * $GIT_NO_REPLACE_OBJECTS is set, but is set to false by some
 907 * commands that do not want replace references to be active.
 908 */
 909extern int read_replace_refs;
 910extern char *git_replace_ref_base;
 911
 912extern int fsync_object_files;
 913extern int core_preload_index;
 914extern int core_apply_sparse_checkout;
 915extern int precomposed_unicode;
 916extern int protect_hfs;
 917extern int protect_ntfs;
 918extern const char *core_fsmonitor;
 919
 920/*
 921 * Include broken refs in all ref iterations, which will
 922 * generally choke dangerous operations rather than letting
 923 * them silently proceed without taking the broken ref into
 924 * account.
 925 */
 926extern int ref_paranoia;
 927
 928/*
 929 * Returns the boolean value of $GIT_OPTIONAL_LOCKS (or the default value).
 930 */
 931int use_optional_locks(void);
 932
 933/*
 934 * The character that begins a commented line in user-editable file
 935 * that is subject to stripspace.
 936 */
 937extern char comment_line_char;
 938extern int auto_comment_line_char;
 939
 940enum log_refs_config {
 941        LOG_REFS_UNSET = -1,
 942        LOG_REFS_NONE = 0,
 943        LOG_REFS_NORMAL,
 944        LOG_REFS_ALWAYS
 945};
 946extern enum log_refs_config log_all_ref_updates;
 947
 948enum rebase_setup_type {
 949        AUTOREBASE_NEVER = 0,
 950        AUTOREBASE_LOCAL,
 951        AUTOREBASE_REMOTE,
 952        AUTOREBASE_ALWAYS
 953};
 954
 955enum push_default_type {
 956        PUSH_DEFAULT_NOTHING = 0,
 957        PUSH_DEFAULT_MATCHING,
 958        PUSH_DEFAULT_SIMPLE,
 959        PUSH_DEFAULT_UPSTREAM,
 960        PUSH_DEFAULT_CURRENT,
 961        PUSH_DEFAULT_UNSPECIFIED
 962};
 963
 964extern enum rebase_setup_type autorebase;
 965extern enum push_default_type push_default;
 966
 967enum object_creation_mode {
 968        OBJECT_CREATION_USES_HARDLINKS = 0,
 969        OBJECT_CREATION_USES_RENAMES = 1
 970};
 971
 972extern enum object_creation_mode object_creation_mode;
 973
 974extern char *notes_ref_name;
 975
 976extern int grafts_replace_parents;
 977
 978/*
 979 * GIT_REPO_VERSION is the version we write by default. The
 980 * _READ variant is the highest number we know how to
 981 * handle.
 982 */
 983#define GIT_REPO_VERSION 0
 984#define GIT_REPO_VERSION_READ 1
 985extern int repository_format_precious_objects;
 986extern char *repository_format_partial_clone;
 987extern const char *core_partial_clone_filter_default;
 988extern int repository_format_worktree_config;
 989
 990/*
 991 * You _have_ to initialize a `struct repository_format` using
 992 * `= REPOSITORY_FORMAT_INIT` before calling `read_repository_format()`.
 993 */
 994struct repository_format {
 995        int version;
 996        int precious_objects;
 997        char *partial_clone; /* value of extensions.partialclone */
 998        int worktree_config;
 999        int is_bare;
1000        int hash_algo;
1001        char *work_tree;
1002        struct string_list unknown_extensions;
1003};
1004
1005/*
1006 * Always use this to initialize a `struct repository_format`
1007 * to a well-defined, default state before calling
1008 * `read_repository()`.
1009 */
1010#define REPOSITORY_FORMAT_INIT \
1011{ \
1012        .version = -1, \
1013        .is_bare = -1, \
1014        .hash_algo = GIT_HASH_SHA1, \
1015        .unknown_extensions = STRING_LIST_INIT_DUP, \
1016}
1017
1018/*
1019 * Read the repository format characteristics from the config file "path" into
1020 * "format" struct. Returns the numeric version. On error, or if no version is
1021 * found in the configuration, -1 is returned, format->version is set to -1,
1022 * and all other fields in the struct are set to the default configuration
1023 * (REPOSITORY_FORMAT_INIT). Always initialize the struct using
1024 * REPOSITORY_FORMAT_INIT before calling this function.
1025 */
1026int read_repository_format(struct repository_format *format, const char *path);
1027
1028/*
1029 * Free the memory held onto by `format`, but not the struct itself.
1030 * (No need to use this after `read_repository_format()` fails.)
1031 */
1032void clear_repository_format(struct repository_format *format);
1033
1034/*
1035 * Verify that the repository described by repository_format is something we
1036 * can read. If it is, return 0. Otherwise, return -1, and "err" will describe
1037 * any errors encountered.
1038 */
1039int verify_repository_format(const struct repository_format *format,
1040                             struct strbuf *err);
1041
1042/*
1043 * Check the repository format version in the path found in get_git_dir(),
1044 * and die if it is a version we don't understand. Generally one would
1045 * set_git_dir() before calling this, and use it only for "are we in a valid
1046 * repo?".
1047 */
1048void check_repository_format(void);
1049
1050#define MTIME_CHANGED   0x0001
1051#define CTIME_CHANGED   0x0002
1052#define OWNER_CHANGED   0x0004
1053#define MODE_CHANGED    0x0008
1054#define INODE_CHANGED   0x0010
1055#define DATA_CHANGED    0x0020
1056#define TYPE_CHANGED    0x0040
1057
1058/*
1059 * Return an abbreviated sha1 unique within this repository's object database.
1060 * The result will be at least `len` characters long, and will be NUL
1061 * terminated.
1062 *
1063 * The non-`_r` version returns a static buffer which remains valid until 4
1064 * more calls to find_unique_abbrev are made.
1065 *
1066 * The `_r` variant writes to a buffer supplied by the caller, which must be at
1067 * least `GIT_MAX_HEXSZ + 1` bytes. The return value is the number of bytes
1068 * written (excluding the NUL terminator).
1069 *
1070 * Note that while this version avoids the static buffer, it is not fully
1071 * reentrant, as it calls into other non-reentrant git code.
1072 */
1073const char *repo_find_unique_abbrev(struct repository *r, const struct object_id *oid, int len);
1074#define find_unique_abbrev(oid, len) repo_find_unique_abbrev(the_repository, oid, len)
1075int repo_find_unique_abbrev_r(struct repository *r, char *hex, const struct object_id *oid, int len);
1076#define find_unique_abbrev_r(hex, oid, len) repo_find_unique_abbrev_r(the_repository, hex, oid, len)
1077
1078extern const unsigned char null_sha1[GIT_MAX_RAWSZ];
1079extern const struct object_id null_oid;
1080
1081static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
1082{
1083        /*
1084         * Teach the compiler that there are only two possibilities of hash size
1085         * here, so that it can optimize for this case as much as possible.
1086         */
1087        if (the_hash_algo->rawsz == GIT_MAX_RAWSZ)
1088                return memcmp(sha1, sha2, GIT_MAX_RAWSZ);
1089        return memcmp(sha1, sha2, GIT_SHA1_RAWSZ);
1090}
1091
1092static inline int oidcmp(const struct object_id *oid1, const struct object_id *oid2)
1093{
1094        return hashcmp(oid1->hash, oid2->hash);
1095}
1096
1097static inline int hasheq(const unsigned char *sha1, const unsigned char *sha2)
1098{
1099        /*
1100         * We write this here instead of deferring to hashcmp so that the
1101         * compiler can properly inline it and avoid calling memcmp.
1102         */
1103        if (the_hash_algo->rawsz == GIT_MAX_RAWSZ)
1104                return !memcmp(sha1, sha2, GIT_MAX_RAWSZ);
1105        return !memcmp(sha1, sha2, GIT_SHA1_RAWSZ);
1106}
1107
1108static inline int oideq(const struct object_id *oid1, const struct object_id *oid2)
1109{
1110        return hasheq(oid1->hash, oid2->hash);
1111}
1112
1113static inline int is_null_sha1(const unsigned char *sha1)
1114{
1115        return hasheq(sha1, null_sha1);
1116}
1117
1118static inline int is_null_oid(const struct object_id *oid)
1119{
1120        return hasheq(oid->hash, null_sha1);
1121}
1122
1123static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
1124{
1125        memcpy(sha_dst, sha_src, the_hash_algo->rawsz);
1126}
1127
1128static inline void oidcpy(struct object_id *dst, const struct object_id *src)
1129{
1130        memcpy(dst->hash, src->hash, GIT_MAX_RAWSZ);
1131}
1132
1133static inline struct object_id *oiddup(const struct object_id *src)
1134{
1135        struct object_id *dst = xmalloc(sizeof(struct object_id));
1136        oidcpy(dst, src);
1137        return dst;
1138}
1139
1140static inline void hashclr(unsigned char *hash)
1141{
1142        memset(hash, 0, the_hash_algo->rawsz);
1143}
1144
1145static inline void oidclr(struct object_id *oid)
1146{
1147        memset(oid->hash, 0, GIT_MAX_RAWSZ);
1148}
1149
1150static inline void oidread(struct object_id *oid, const unsigned char *hash)
1151{
1152        memcpy(oid->hash, hash, the_hash_algo->rawsz);
1153}
1154
1155static inline int is_empty_blob_sha1(const unsigned char *sha1)
1156{
1157        return hasheq(sha1, the_hash_algo->empty_blob->hash);
1158}
1159
1160static inline int is_empty_blob_oid(const struct object_id *oid)
1161{
1162        return oideq(oid, the_hash_algo->empty_blob);
1163}
1164
1165static inline int is_empty_tree_sha1(const unsigned char *sha1)
1166{
1167        return hasheq(sha1, the_hash_algo->empty_tree->hash);
1168}
1169
1170static inline int is_empty_tree_oid(const struct object_id *oid)
1171{
1172        return oideq(oid, the_hash_algo->empty_tree);
1173}
1174
1175const char *empty_tree_oid_hex(void);
1176const char *empty_blob_oid_hex(void);
1177
1178/* set default permissions by passing mode arguments to open(2) */
1179int git_mkstemps_mode(char *pattern, int suffix_len, int mode);
1180int git_mkstemp_mode(char *pattern, int mode);
1181
1182/*
1183 * NOTE NOTE NOTE!!
1184 *
1185 * PERM_UMASK, OLD_PERM_GROUP and OLD_PERM_EVERYBODY enumerations must
1186 * not be changed. Old repositories have core.sharedrepository written in
1187 * numeric format, and therefore these values are preserved for compatibility
1188 * reasons.
1189 */
1190enum sharedrepo {
1191        PERM_UMASK          = 0,
1192        OLD_PERM_GROUP      = 1,
1193        OLD_PERM_EVERYBODY  = 2,
1194        PERM_GROUP          = 0660,
1195        PERM_EVERYBODY      = 0664
1196};
1197int git_config_perm(const char *var, const char *value);
1198int adjust_shared_perm(const char *path);
1199
1200/*
1201 * Create the directory containing the named path, using care to be
1202 * somewhat safe against races. Return one of the scld_error values to
1203 * indicate success/failure. On error, set errno to describe the
1204 * problem.
1205 *
1206 * SCLD_VANISHED indicates that one of the ancestor directories of the
1207 * path existed at one point during the function call and then
1208 * suddenly vanished, probably because another process pruned the
1209 * directory while we were working.  To be robust against this kind of
1210 * race, callers might want to try invoking the function again when it
1211 * returns SCLD_VANISHED.
1212 *
1213 * safe_create_leading_directories() temporarily changes path while it
1214 * is working but restores it before returning.
1215 * safe_create_leading_directories_const() doesn't modify path, even
1216 * temporarily.
1217 */
1218enum scld_error {
1219        SCLD_OK = 0,
1220        SCLD_FAILED = -1,
1221        SCLD_PERMS = -2,
1222        SCLD_EXISTS = -3,
1223        SCLD_VANISHED = -4
1224};
1225enum scld_error safe_create_leading_directories(char *path);
1226enum scld_error safe_create_leading_directories_const(const char *path);
1227
1228/*
1229 * Callback function for raceproof_create_file(). This function is
1230 * expected to do something that makes dirname(path) permanent despite
1231 * the fact that other processes might be cleaning up empty
1232 * directories at the same time. Usually it will create a file named
1233 * path, but alternatively it could create another file in that
1234 * directory, or even chdir() into that directory. The function should
1235 * return 0 if the action was completed successfully. On error, it
1236 * should return a nonzero result and set errno.
1237 * raceproof_create_file() treats two errno values specially:
1238 *
1239 * - ENOENT -- dirname(path) does not exist. In this case,
1240 *             raceproof_create_file() tries creating dirname(path)
1241 *             (and any parent directories, if necessary) and calls
1242 *             the function again.
1243 *
1244 * - EISDIR -- the file already exists and is a directory. In this
1245 *             case, raceproof_create_file() removes the directory if
1246 *             it is empty (and recursively any empty directories that
1247 *             it contains) and calls the function again.
1248 *
1249 * Any other errno causes raceproof_create_file() to fail with the
1250 * callback's return value and errno.
1251 *
1252 * Obviously, this function should be OK with being called again if it
1253 * fails with ENOENT or EISDIR. In other scenarios it will not be
1254 * called again.
1255 */
1256typedef int create_file_fn(const char *path, void *cb);
1257
1258/*
1259 * Create a file in dirname(path) by calling fn, creating leading
1260 * directories if necessary. Retry a few times in case we are racing
1261 * with another process that is trying to clean up the directory that
1262 * contains path. See the documentation for create_file_fn for more
1263 * details.
1264 *
1265 * Return the value and set the errno that resulted from the most
1266 * recent call of fn. fn is always called at least once, and will be
1267 * called more than once if it returns ENOENT or EISDIR.
1268 */
1269int raceproof_create_file(const char *path, create_file_fn fn, void *cb);
1270
1271int mkdir_in_gitdir(const char *path);
1272char *expand_user_path(const char *path, int real_home);
1273const char *enter_repo(const char *path, int strict);
1274static inline int is_absolute_path(const char *path)
1275{
1276        return is_dir_sep(path[0]) || has_dos_drive_prefix(path);
1277}
1278int is_directory(const char *);
1279char *strbuf_realpath(struct strbuf *resolved, const char *path,
1280                      int die_on_error);
1281const char *real_path(const char *path);
1282const char *real_path_if_valid(const char *path);
1283char *real_pathdup(const char *path, int die_on_error);
1284const char *absolute_path(const char *path);
1285char *absolute_pathdup(const char *path);
1286const char *remove_leading_path(const char *in, const char *prefix);
1287const char *relative_path(const char *in, const char *prefix, struct strbuf *sb);
1288int normalize_path_copy_len(char *dst, const char *src, int *prefix_len);
1289int normalize_path_copy(char *dst, const char *src);
1290int longest_ancestor_length(const char *path, struct string_list *prefixes);
1291char *strip_path_suffix(const char *path, const char *suffix);
1292int daemon_avoid_alias(const char *path);
1293
1294/*
1295 * These functions match their is_hfs_dotgit() counterparts; see utf8.h for
1296 * details.
1297 */
1298int is_ntfs_dotgit(const char *name);
1299int is_ntfs_dotgitmodules(const char *name);
1300int is_ntfs_dotgitignore(const char *name);
1301int is_ntfs_dotgitattributes(const char *name);
1302
1303/*
1304 * Returns true iff "str" could be confused as a command-line option when
1305 * passed to a sub-program like "ssh". Note that this has nothing to do with
1306 * shell-quoting, which should be handled separately; we're assuming here that
1307 * the string makes it verbatim to the sub-program.
1308 */
1309int looks_like_command_line_option(const char *str);
1310
1311/**
1312 * Return a newly allocated string with the evaluation of
1313 * "$XDG_CONFIG_HOME/git/$filename" if $XDG_CONFIG_HOME is non-empty, otherwise
1314 * "$HOME/.config/git/$filename". Return NULL upon error.
1315 */
1316char *xdg_config_home(const char *filename);
1317
1318/**
1319 * Return a newly allocated string with the evaluation of
1320 * "$XDG_CACHE_HOME/git/$filename" if $XDG_CACHE_HOME is non-empty, otherwise
1321 * "$HOME/.cache/git/$filename". Return NULL upon error.
1322 */
1323char *xdg_cache_home(const char *filename);
1324
1325int git_open_cloexec(const char *name, int flags);
1326#define git_open(name) git_open_cloexec(name, O_RDONLY)
1327int unpack_loose_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz);
1328int parse_loose_header(const char *hdr, unsigned long *sizep);
1329
1330int check_object_signature(const struct object_id *oid, void *buf, unsigned long size, const char *type);
1331
1332int finalize_object_file(const char *tmpfile, const char *filename);
1333
1334/* Helper to check and "touch" a file */
1335int check_and_freshen_file(const char *fn, int freshen);
1336
1337extern const signed char hexval_table[256];
1338static inline unsigned int hexval(unsigned char c)
1339{
1340        return hexval_table[c];
1341}
1342
1343/*
1344 * Convert two consecutive hexadecimal digits into a char.  Return a
1345 * negative value on error.  Don't run over the end of short strings.
1346 */
1347static inline int hex2chr(const char *s)
1348{
1349        unsigned int val = hexval(s[0]);
1350        return (val & ~0xf) ? val : (val << 4) | hexval(s[1]);
1351}
1352
1353/* Convert to/from hex/sha1 representation */
1354#define MINIMUM_ABBREV minimum_abbrev
1355#define DEFAULT_ABBREV default_abbrev
1356
1357/* used when the code does not know or care what the default abbrev is */
1358#define FALLBACK_DEFAULT_ABBREV 7
1359
1360struct object_context {
1361        unsigned short mode;
1362        /*
1363         * symlink_path is only used by get_tree_entry_follow_symlinks,
1364         * and only for symlinks that point outside the repository.
1365         */
1366        struct strbuf symlink_path;
1367        /*
1368         * If GET_OID_RECORD_PATH is set, this will record path (if any)
1369         * found when resolving the name. The caller is responsible for
1370         * releasing the memory.
1371         */
1372        char *path;
1373};
1374
1375#define GET_OID_QUIETLY           01
1376#define GET_OID_COMMIT            02
1377#define GET_OID_COMMITTISH        04
1378#define GET_OID_TREE             010
1379#define GET_OID_TREEISH          020
1380#define GET_OID_BLOB             040
1381#define GET_OID_FOLLOW_SYMLINKS 0100
1382#define GET_OID_RECORD_PATH     0200
1383#define GET_OID_ONLY_TO_DIE    04000
1384
1385#define GET_OID_DISAMBIGUATORS \
1386        (GET_OID_COMMIT | GET_OID_COMMITTISH | \
1387        GET_OID_TREE | GET_OID_TREEISH | \
1388        GET_OID_BLOB)
1389
1390enum get_oid_result {
1391        FOUND = 0,
1392        MISSING_OBJECT = -1, /* The requested object is missing */
1393        SHORT_NAME_AMBIGUOUS = -2,
1394        /* The following only apply when symlinks are followed */
1395        DANGLING_SYMLINK = -4, /*
1396                                * The initial symlink is there, but
1397                                * (transitively) points to a missing
1398                                * in-tree file
1399                                */
1400        SYMLINK_LOOP = -5,
1401        NOT_DIR = -6, /*
1402                       * Somewhere along the symlink chain, a path is
1403                       * requested which contains a file as a
1404                       * non-final element.
1405                       */
1406};
1407
1408int repo_get_oid(struct repository *r, const char *str, struct object_id *oid);
1409int get_oidf(struct object_id *oid, const char *fmt, ...);
1410int repo_get_oid_commit(struct repository *r, const char *str, struct object_id *oid);
1411int repo_get_oid_committish(struct repository *r, const char *str, struct object_id *oid);
1412int repo_get_oid_tree(struct repository *r, const char *str, struct object_id *oid);
1413int repo_get_oid_treeish(struct repository *r, const char *str, struct object_id *oid);
1414int repo_get_oid_blob(struct repository *r, const char *str, struct object_id *oid);
1415int repo_get_oid_mb(struct repository *r, const char *str, struct object_id *oid);
1416void maybe_die_on_misspelt_object_name(struct repository *repo,
1417                                       const char *name,
1418                                       const char *prefix);
1419enum get_oid_result get_oid_with_context(struct repository *repo, const char *str,
1420                                         unsigned flags, struct object_id *oid,
1421                                         struct object_context *oc);
1422
1423#define get_oid(str, oid)               repo_get_oid(the_repository, str, oid)
1424#define get_oid_commit(str, oid)        repo_get_oid_commit(the_repository, str, oid)
1425#define get_oid_committish(str, oid)    repo_get_oid_committish(the_repository, str, oid)
1426#define get_oid_tree(str, oid)          repo_get_oid_tree(the_repository, str, oid)
1427#define get_oid_treeish(str, oid)       repo_get_oid_treeish(the_repository, str, oid)
1428#define get_oid_blob(str, oid)          repo_get_oid_blob(the_repository, str, oid)
1429#define get_oid_mb(str, oid)            repo_get_oid_mb(the_repository, str, oid)
1430
1431typedef int each_abbrev_fn(const struct object_id *oid, void *);
1432int repo_for_each_abbrev(struct repository *r, const char *prefix, each_abbrev_fn, void *);
1433#define for_each_abbrev(prefix, fn, data) repo_for_each_abbrev(the_repository, prefix, fn, data)
1434
1435int set_disambiguate_hint_config(const char *var, const char *value);
1436
1437/*
1438 * Try to read a SHA1 in hexadecimal format from the 40 characters
1439 * starting at hex.  Write the 20-byte result to sha1 in binary form.
1440 * Return 0 on success.  Reading stops if a NUL is encountered in the
1441 * input, so it is safe to pass this function an arbitrary
1442 * null-terminated string.
1443 */
1444int get_sha1_hex(const char *hex, unsigned char *sha1);
1445int get_oid_hex(const char *hex, struct object_id *sha1);
1446
1447/*
1448 * Read `len` pairs of hexadecimal digits from `hex` and write the
1449 * values to `binary` as `len` bytes. Return 0 on success, or -1 if
1450 * the input does not consist of hex digits).
1451 */
1452int hex_to_bytes(unsigned char *binary, const char *hex, size_t len);
1453
1454/*
1455 * Convert a binary hash to its hex equivalent. The `_r` variant is reentrant,
1456 * and writes the NUL-terminated output to the buffer `out`, which must be at
1457 * least `GIT_MAX_HEXSZ + 1` bytes, and returns a pointer to out for
1458 * convenience.
1459 *
1460 * The non-`_r` variant returns a static buffer, but uses a ring of 4
1461 * buffers, making it safe to make multiple calls for a single statement, like:
1462 *
1463 *   printf("%s -> %s", sha1_to_hex(one), sha1_to_hex(two));
1464 */
1465char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash, const struct git_hash_algo *);
1466char *sha1_to_hex_r(char *out, const unsigned char *sha1);
1467char *oid_to_hex_r(char *out, const struct object_id *oid);
1468char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *);       /* static buffer result! */
1469char *sha1_to_hex(const unsigned char *sha1);                                           /* same static buffer */
1470char *hash_to_hex(const unsigned char *hash);                                           /* same static buffer */
1471char *oid_to_hex(const struct object_id *oid);                                          /* same static buffer */
1472
1473/*
1474 * Parse a 40-character hexadecimal object ID starting from hex, updating the
1475 * pointer specified by end when parsing stops.  The resulting object ID is
1476 * stored in oid.  Returns 0 on success.  Parsing will stop on the first NUL or
1477 * other invalid character.  end is only updated on success; otherwise, it is
1478 * unmodified.
1479 */
1480int parse_oid_hex(const char *hex, struct object_id *oid, const char **end);
1481
1482/*
1483 * This reads short-hand syntax that not only evaluates to a commit
1484 * object name, but also can act as if the end user spelled the name
1485 * of the branch from the command line.
1486 *
1487 * - "@{-N}" finds the name of the Nth previous branch we were on, and
1488 *   places the name of the branch in the given buf and returns the
1489 *   number of characters parsed if successful.
1490 *
1491 * - "<branch>@{upstream}" finds the name of the other ref that
1492 *   <branch> is configured to merge with (missing <branch> defaults
1493 *   to the current branch), and places the name of the branch in the
1494 *   given buf and returns the number of characters parsed if
1495 *   successful.
1496 *
1497 * If the input is not of the accepted format, it returns a negative
1498 * number to signal an error.
1499 *
1500 * If the input was ok but there are not N branch switches in the
1501 * reflog, it returns 0.
1502 *
1503 * If "allowed" is non-zero, it is a treated as a bitfield of allowable
1504 * expansions: local branches ("refs/heads/"), remote branches
1505 * ("refs/remotes/"), or "HEAD". If no "allowed" bits are set, any expansion is
1506 * allowed, even ones to refs outside of those namespaces.
1507 */
1508#define INTERPRET_BRANCH_LOCAL (1<<0)
1509#define INTERPRET_BRANCH_REMOTE (1<<1)
1510#define INTERPRET_BRANCH_HEAD (1<<2)
1511int repo_interpret_branch_name(struct repository *r,
1512                               const char *str, int len,
1513                               struct strbuf *buf,
1514                               unsigned allowed);
1515#define interpret_branch_name(str, len, buf, allowed) \
1516        repo_interpret_branch_name(the_repository, str, len, buf, allowed)
1517
1518int validate_headref(const char *ref);
1519
1520int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
1521int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
1522int name_compare(const char *name1, size_t len1, const char *name2, size_t len2);
1523int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2);
1524
1525void *read_object_with_reference(const struct object_id *oid,
1526                                 const char *required_type,
1527                                 unsigned long *size,
1528                                 struct object_id *oid_ret);
1529
1530struct object *repo_peel_to_type(struct repository *r,
1531                                 const char *name, int namelen,
1532                                 struct object *o, enum object_type);
1533#define peel_to_type(name, namelen, obj, type) \
1534        repo_peel_to_type(the_repository, name, namelen, obj, type)
1535
1536enum date_mode_type {
1537        DATE_NORMAL = 0,
1538        DATE_HUMAN,
1539        DATE_RELATIVE,
1540        DATE_SHORT,
1541        DATE_ISO8601,
1542        DATE_ISO8601_STRICT,
1543        DATE_RFC2822,
1544        DATE_STRFTIME,
1545        DATE_RAW,
1546        DATE_UNIX
1547};
1548
1549struct date_mode {
1550        enum date_mode_type type;
1551        const char *strftime_fmt;
1552        int local;
1553};
1554
1555/*
1556 * Convenience helper for passing a constant type, like:
1557 *
1558 *   show_date(t, tz, DATE_MODE(NORMAL));
1559 */
1560#define DATE_MODE(t) date_mode_from_type(DATE_##t)
1561struct date_mode *date_mode_from_type(enum date_mode_type type);
1562
1563const char *show_date(timestamp_t time, int timezone, const struct date_mode *mode);
1564void show_date_relative(timestamp_t time, const struct timeval *now,
1565                        struct strbuf *timebuf);
1566void show_date_human(timestamp_t time, int tz, const struct timeval *now,
1567                        struct strbuf *timebuf);
1568int parse_date(const char *date, struct strbuf *out);
1569int parse_date_basic(const char *date, timestamp_t *timestamp, int *offset);
1570int parse_expiry_date(const char *date, timestamp_t *timestamp);
1571void datestamp(struct strbuf *out);
1572#define approxidate(s) approxidate_careful((s), NULL)
1573timestamp_t approxidate_careful(const char *, int *);
1574timestamp_t approxidate_relative(const char *date, const struct timeval *now);
1575void parse_date_format(const char *format, struct date_mode *mode);
1576int date_overflows(timestamp_t date);
1577
1578#define IDENT_STRICT           1
1579#define IDENT_NO_DATE          2
1580#define IDENT_NO_NAME          4
1581
1582enum want_ident {
1583        WANT_BLANK_IDENT,
1584        WANT_AUTHOR_IDENT,
1585        WANT_COMMITTER_IDENT
1586};
1587
1588const char *git_author_info(int);
1589const char *git_committer_info(int);
1590const char *fmt_ident(const char *name, const char *email,
1591                      enum want_ident whose_ident,
1592                      const char *date_str, int);
1593const char *fmt_name(enum want_ident);
1594const char *ident_default_name(void);
1595const char *ident_default_email(void);
1596const char *git_editor(void);
1597const char *git_sequence_editor(void);
1598const char *git_pager(int stdout_is_tty);
1599int is_terminal_dumb(void);
1600int git_ident_config(const char *, const char *, void *);
1601/*
1602 * Prepare an ident to fall back on if the user didn't configure it.
1603 */
1604void prepare_fallback_ident(const char *name, const char *email);
1605void reset_ident_date(void);
1606
1607struct ident_split {
1608        const char *name_begin;
1609        const char *name_end;
1610        const char *mail_begin;
1611        const char *mail_end;
1612        const char *date_begin;
1613        const char *date_end;
1614        const char *tz_begin;
1615        const char *tz_end;
1616};
1617/*
1618 * Signals an success with 0, but time part of the result may be NULL
1619 * if the input lacks timestamp and zone
1620 */
1621int split_ident_line(struct ident_split *, const char *, int);
1622
1623/*
1624 * Like show_date, but pull the timestamp and tz parameters from
1625 * the ident_split. It will also sanity-check the values and produce
1626 * a well-known sentinel date if they appear bogus.
1627 */
1628const char *show_ident_date(const struct ident_split *id,
1629                            const struct date_mode *mode);
1630
1631/*
1632 * Compare split idents for equality or strict ordering. Note that we
1633 * compare only the ident part of the line, ignoring any timestamp.
1634 *
1635 * Because there are two fields, we must choose one as the primary key; we
1636 * currently arbitrarily pick the email.
1637 */
1638int ident_cmp(const struct ident_split *, const struct ident_split *);
1639
1640struct checkout {
1641        struct index_state *istate;
1642        const char *base_dir;
1643        int base_dir_len;
1644        struct delayed_checkout *delayed_checkout;
1645        unsigned force:1,
1646                 quiet:1,
1647                 not_new:1,
1648                 clone:1,
1649                 refresh_cache:1;
1650};
1651#define CHECKOUT_INIT { NULL, "" }
1652
1653#define TEMPORARY_FILENAME_LENGTH 25
1654int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath, int *nr_checkouts);
1655void enable_delayed_checkout(struct checkout *state);
1656int finish_delayed_checkout(struct checkout *state, int *nr_checkouts);
1657/*
1658 * Unlink the last component and schedule the leading directories for
1659 * removal, such that empty directories get removed.
1660 */
1661void unlink_entry(const struct cache_entry *ce);
1662
1663struct cache_def {
1664        struct strbuf path;
1665        int flags;
1666        int track_flags;
1667        int prefix_len_stat_func;
1668};
1669#define CACHE_DEF_INIT { STRBUF_INIT, 0, 0, 0 }
1670static inline void cache_def_clear(struct cache_def *cache)
1671{
1672        strbuf_release(&cache->path);
1673}
1674
1675int has_symlink_leading_path(const char *name, int len);
1676int threaded_has_symlink_leading_path(struct cache_def *, const char *, int);
1677int check_leading_path(const char *name, int len);
1678int has_dirs_only_path(const char *name, int len, int prefix_len);
1679void schedule_dir_for_removal(const char *name, int len);
1680void remove_scheduled_dirs(void);
1681
1682struct pack_window {
1683        struct pack_window *next;
1684        unsigned char *base;
1685        off_t offset;
1686        size_t len;
1687        unsigned int last_used;
1688        unsigned int inuse_cnt;
1689};
1690
1691struct pack_entry {
1692        off_t offset;
1693        struct packed_git *p;
1694};
1695
1696/*
1697 * Create a temporary file rooted in the object database directory, or
1698 * die on failure. The filename is taken from "pattern", which should have the
1699 * usual "XXXXXX" trailer, and the resulting filename is written into the
1700 * "template" buffer. Returns the open descriptor.
1701 */
1702int odb_mkstemp(struct strbuf *temp_filename, const char *pattern);
1703
1704/*
1705 * Create a pack .keep file named "name" (which should generally be the output
1706 * of odb_pack_name). Returns a file descriptor opened for writing, or -1 on
1707 * error.
1708 */
1709int odb_pack_keep(const char *name);
1710
1711/*
1712 * Set this to 0 to prevent oid_object_info_extended() from fetching missing
1713 * blobs. This has a difference only if extensions.partialClone is set.
1714 *
1715 * Its default value is 1.
1716 */
1717extern int fetch_if_missing;
1718
1719/* Dumb servers support */
1720int update_server_info(int);
1721
1722const char *get_log_output_encoding(void);
1723const char *get_commit_output_encoding(void);
1724
1725/*
1726 * This is a hack for test programs like test-dump-untracked-cache to
1727 * ensure that they do not modify the untracked cache when reading it.
1728 * Do not use it otherwise!
1729 */
1730extern int ignore_untracked_cache_config;
1731
1732int committer_ident_sufficiently_given(void);
1733int author_ident_sufficiently_given(void);
1734
1735extern const char *git_commit_encoding;
1736extern const char *git_log_output_encoding;
1737extern const char *git_mailmap_file;
1738extern const char *git_mailmap_blob;
1739
1740/* IO helper functions */
1741void maybe_flush_or_die(FILE *, const char *);
1742__attribute__((format (printf, 2, 3)))
1743void fprintf_or_die(FILE *, const char *fmt, ...);
1744
1745#define COPY_READ_ERROR (-2)
1746#define COPY_WRITE_ERROR (-3)
1747int copy_fd(int ifd, int ofd);
1748int copy_file(const char *dst, const char *src, int mode);
1749int copy_file_with_time(const char *dst, const char *src, int mode);
1750
1751void write_or_die(int fd, const void *buf, size_t count);
1752void fsync_or_die(int fd, const char *);
1753
1754ssize_t read_in_full(int fd, void *buf, size_t count);
1755ssize_t write_in_full(int fd, const void *buf, size_t count);
1756ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset);
1757
1758static inline ssize_t write_str_in_full(int fd, const char *str)
1759{
1760        return write_in_full(fd, str, strlen(str));
1761}
1762
1763/**
1764 * Open (and truncate) the file at path, write the contents of buf to it,
1765 * and close it. Dies if any errors are encountered.
1766 */
1767void write_file_buf(const char *path, const char *buf, size_t len);
1768
1769/**
1770 * Like write_file_buf(), but format the contents into a buffer first.
1771 * Additionally, write_file() will append a newline if one is not already
1772 * present, making it convenient to write text files:
1773 *
1774 *   write_file(path, "counter: %d", ctr);
1775 */
1776__attribute__((format (printf, 2, 3)))
1777void write_file(const char *path, const char *fmt, ...);
1778
1779/* pager.c */
1780void setup_pager(void);
1781int pager_in_use(void);
1782extern int pager_use_color;
1783int term_columns(void);
1784int decimal_width(uintmax_t);
1785int check_pager_config(const char *cmd);
1786void prepare_pager_args(struct child_process *, const char *pager);
1787
1788extern const char *editor_program;
1789extern const char *askpass_program;
1790extern const char *excludes_file;
1791
1792/* base85 */
1793int decode_85(char *dst, const char *line, int linelen);
1794void encode_85(char *buf, const unsigned char *data, int bytes);
1795
1796/* pkt-line.c */
1797void packet_trace_identity(const char *prog);
1798
1799/* add */
1800/*
1801 * return 0 if success, 1 - if addition of a file failed and
1802 * ADD_FILES_IGNORE_ERRORS was specified in flags
1803 */
1804int add_files_to_cache(const char *prefix, const struct pathspec *pathspec, int flags);
1805
1806/* diff.c */
1807extern int diff_auto_refresh_index;
1808
1809/* match-trees.c */
1810void shift_tree(const struct object_id *, const struct object_id *, struct object_id *, int);
1811void shift_tree_by(const struct object_id *, const struct object_id *, struct object_id *, const char *);
1812
1813/*
1814 * whitespace rules.
1815 * used by both diff and apply
1816 * last two digits are tab width
1817 */
1818#define WS_BLANK_AT_EOL         0100
1819#define WS_SPACE_BEFORE_TAB     0200
1820#define WS_INDENT_WITH_NON_TAB  0400
1821#define WS_CR_AT_EOL           01000
1822#define WS_BLANK_AT_EOF        02000
1823#define WS_TAB_IN_INDENT       04000
1824#define WS_TRAILING_SPACE      (WS_BLANK_AT_EOL|WS_BLANK_AT_EOF)
1825#define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB|8)
1826#define WS_TAB_WIDTH_MASK        077
1827/* All WS_* -- when extended, adapt diff.c emit_symbol */
1828#define WS_RULE_MASK           07777
1829extern unsigned whitespace_rule_cfg;
1830unsigned whitespace_rule(struct index_state *, const char *);
1831unsigned parse_whitespace_rule(const char *);
1832unsigned ws_check(const char *line, int len, unsigned ws_rule);
1833void ws_check_emit(const char *line, int len, unsigned ws_rule, FILE *stream, const char *set, const char *reset, const char *ws);
1834char *whitespace_error_string(unsigned ws);
1835void ws_fix_copy(struct strbuf *, const char *, int, unsigned, int *);
1836int ws_blank_line(const char *line, int len, unsigned ws_rule);
1837#define ws_tab_width(rule)     ((rule) & WS_TAB_WIDTH_MASK)
1838
1839/* ls-files */
1840void overlay_tree_on_index(struct index_state *istate,
1841                           const char *tree_name, const char *prefix);
1842
1843/* setup.c */
1844struct startup_info {
1845        int have_repository;
1846        const char *prefix;
1847};
1848extern struct startup_info *startup_info;
1849
1850/* merge.c */
1851struct commit_list;
1852int try_merge_command(struct repository *r,
1853                const char *strategy, size_t xopts_nr,
1854                const char **xopts, struct commit_list *common,
1855                const char *head_arg, struct commit_list *remotes);
1856int checkout_fast_forward(struct repository *r,
1857                          const struct object_id *from,
1858                          const struct object_id *to,
1859                          int overwrite_ignore);
1860
1861
1862int sane_execvp(const char *file, char *const argv[]);
1863
1864/*
1865 * A struct to encapsulate the concept of whether a file has changed
1866 * since we last checked it. This uses criteria similar to those used
1867 * for the index.
1868 */
1869struct stat_validity {
1870        struct stat_data *sd;
1871};
1872
1873void stat_validity_clear(struct stat_validity *sv);
1874
1875/*
1876 * Returns 1 if the path is a regular file (or a symlink to a regular
1877 * file) and matches the saved stat_validity, 0 otherwise.  A missing
1878 * or inaccessible file is considered a match if the struct was just
1879 * initialized, or if the previous update found an inaccessible file.
1880 */
1881int stat_validity_check(struct stat_validity *sv, const char *path);
1882
1883/*
1884 * Update the stat_validity from a file opened at descriptor fd. If
1885 * the file is missing, inaccessible, or not a regular file, then
1886 * future calls to stat_validity_check will match iff one of those
1887 * conditions continues to be true.
1888 */
1889void stat_validity_update(struct stat_validity *sv, int fd);
1890
1891int versioncmp(const char *s1, const char *s2);
1892void sleep_millisec(int millisec);
1893
1894/*
1895 * Create a directory and (if share is nonzero) adjust its permissions
1896 * according to the shared_repository setting. Only use this for
1897 * directories under $GIT_DIR.  Don't use it for working tree
1898 * directories.
1899 */
1900void safe_create_dir(const char *dir, int share);
1901
1902/*
1903 * Should we print an ellipsis after an abbreviated SHA-1 value
1904 * when doing diff-raw output or indicating a detached HEAD?
1905 */
1906int print_sha1_ellipsis(void);
1907
1908/* Return 1 if the file is empty or does not exists, 0 otherwise. */
1909int is_empty_or_missing_file(const char *filename);
1910
1911#endif /* CACHE_H */