cache.hon commit Merge branch 'cb/filter-branch-prune-empty-degenerate-merges' (6a5713b)
   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 * Some mode bits are also used internally for computations.
  79 *
  80 * They *must* not overlap with any valid modes, and they *must* not be emitted
  81 * to outside world - i.e. appear on disk or network. In other words, it's just
  82 * temporary fields, which we internally use, but they have to stay in-house.
  83 *
  84 * ( such approach is valid, as standard S_IF* fits into 16 bits, and in Git
  85 *   codebase mode is `unsigned int` which is assumed to be at least 32 bits )
  86 */
  87
  88/* used internally in tree-diff */
  89#define S_DIFFTREE_IFXMIN_NEQ   0x80000000
  90
  91
  92/*
  93 * Intensive research over the course of many years has shown that
  94 * port 9418 is totally unused by anything else. Or
  95 *
  96 *      Your search - "port 9418" - did not match any documents.
  97 *
  98 * as www.google.com puts it.
  99 *
 100 * This port has been properly assigned for git use by IANA:
 101 * git (Assigned-9418) [I06-050728-0001].
 102 *
 103 *      git  9418/tcp   git pack transfer service
 104 *      git  9418/udp   git pack transfer service
 105 *
 106 * with Linus Torvalds <torvalds@osdl.org> as the point of
 107 * contact. September 2005.
 108 *
 109 * See http://www.iana.org/assignments/port-numbers
 110 */
 111#define DEFAULT_GIT_PORT 9418
 112
 113/*
 114 * Basic data structures for the directory cache
 115 */
 116
 117#define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
 118struct cache_header {
 119        uint32_t hdr_signature;
 120        uint32_t hdr_version;
 121        uint32_t hdr_entries;
 122};
 123
 124#define INDEX_FORMAT_LB 2
 125#define INDEX_FORMAT_UB 4
 126
 127/*
 128 * The "cache_time" is just the low 32 bits of the
 129 * time. It doesn't matter if it overflows - we only
 130 * check it for equality in the 32 bits we save.
 131 */
 132struct cache_time {
 133        uint32_t sec;
 134        uint32_t nsec;
 135};
 136
 137struct stat_data {
 138        struct cache_time sd_ctime;
 139        struct cache_time sd_mtime;
 140        unsigned int sd_dev;
 141        unsigned int sd_ino;
 142        unsigned int sd_uid;
 143        unsigned int sd_gid;
 144        unsigned int sd_size;
 145};
 146
 147struct cache_entry {
 148        struct hashmap_entry ent;
 149        struct stat_data ce_stat_data;
 150        unsigned int ce_mode;
 151        unsigned int ce_flags;
 152        unsigned int ce_namelen;
 153        unsigned int index;     /* for link extension */
 154        unsigned char sha1[20];
 155        char name[FLEX_ARRAY]; /* more */
 156};
 157
 158#define CE_STAGEMASK (0x3000)
 159#define CE_EXTENDED  (0x4000)
 160#define CE_VALID     (0x8000)
 161#define CE_STAGESHIFT 12
 162
 163/*
 164 * Range 0xFFFF0FFF in ce_flags is divided into
 165 * two parts: in-memory flags and on-disk ones.
 166 * Flags in CE_EXTENDED_FLAGS will get saved on-disk
 167 * if you want to save a new flag, add it in
 168 * CE_EXTENDED_FLAGS
 169 *
 170 * In-memory only flags
 171 */
 172#define CE_UPDATE            (1 << 16)
 173#define CE_REMOVE            (1 << 17)
 174#define CE_UPTODATE          (1 << 18)
 175#define CE_ADDED             (1 << 19)
 176
 177#define CE_HASHED            (1 << 20)
 178#define CE_WT_REMOVE         (1 << 22) /* remove in work directory */
 179#define CE_CONFLICTED        (1 << 23)
 180
 181#define CE_UNPACKED          (1 << 24)
 182#define CE_NEW_SKIP_WORKTREE (1 << 25)
 183
 184/* used to temporarily mark paths matched by pathspecs */
 185#define CE_MATCHED           (1 << 26)
 186
 187#define CE_UPDATE_IN_BASE    (1 << 27)
 188#define CE_STRIP_NAME        (1 << 28)
 189
 190/*
 191 * Extended on-disk flags
 192 */
 193#define CE_INTENT_TO_ADD     (1 << 29)
 194#define CE_SKIP_WORKTREE     (1 << 30)
 195/* CE_EXTENDED2 is for future extension */
 196#define CE_EXTENDED2         (1 << 31)
 197
 198#define CE_EXTENDED_FLAGS (CE_INTENT_TO_ADD | CE_SKIP_WORKTREE)
 199
 200/*
 201 * Safeguard to avoid saving wrong flags:
 202 *  - CE_EXTENDED2 won't get saved until its semantic is known
 203 *  - Bits in 0x0000FFFF have been saved in ce_flags already
 204 *  - Bits in 0x003F0000 are currently in-memory flags
 205 */
 206#if CE_EXTENDED_FLAGS & 0x803FFFFF
 207#error "CE_EXTENDED_FLAGS out of range"
 208#endif
 209
 210struct pathspec;
 211
 212/*
 213 * Copy the sha1 and stat state of a cache entry from one to
 214 * another. But we never change the name, or the hash state!
 215 */
 216static inline void copy_cache_entry(struct cache_entry *dst,
 217                                    const struct cache_entry *src)
 218{
 219        unsigned int state = dst->ce_flags & CE_HASHED;
 220
 221        /* Don't copy hash chain and name */
 222        memcpy(&dst->ce_stat_data, &src->ce_stat_data,
 223                        offsetof(struct cache_entry, name) -
 224                        offsetof(struct cache_entry, ce_stat_data));
 225
 226        /* Restore the hash state */
 227        dst->ce_flags = (dst->ce_flags & ~CE_HASHED) | state;
 228}
 229
 230static inline unsigned create_ce_flags(unsigned stage)
 231{
 232        return (stage << CE_STAGESHIFT);
 233}
 234
 235#define ce_namelen(ce) ((ce)->ce_namelen)
 236#define ce_size(ce) cache_entry_size(ce_namelen(ce))
 237#define ce_stage(ce) ((CE_STAGEMASK & (ce)->ce_flags) >> CE_STAGESHIFT)
 238#define ce_uptodate(ce) ((ce)->ce_flags & CE_UPTODATE)
 239#define ce_skip_worktree(ce) ((ce)->ce_flags & CE_SKIP_WORKTREE)
 240#define ce_mark_uptodate(ce) ((ce)->ce_flags |= CE_UPTODATE)
 241
 242#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 243static inline unsigned int create_ce_mode(unsigned int mode)
 244{
 245        if (S_ISLNK(mode))
 246                return S_IFLNK;
 247        if (S_ISDIR(mode) || S_ISGITLINK(mode))
 248                return S_IFGITLINK;
 249        return S_IFREG | ce_permissions(mode);
 250}
 251static inline unsigned int ce_mode_from_stat(const struct cache_entry *ce,
 252                                             unsigned int mode)
 253{
 254        extern int trust_executable_bit, has_symlinks;
 255        if (!has_symlinks && S_ISREG(mode) &&
 256            ce && S_ISLNK(ce->ce_mode))
 257                return ce->ce_mode;
 258        if (!trust_executable_bit && S_ISREG(mode)) {
 259                if (ce && S_ISREG(ce->ce_mode))
 260                        return ce->ce_mode;
 261                return create_ce_mode(0666);
 262        }
 263        return create_ce_mode(mode);
 264}
 265static inline int ce_to_dtype(const struct cache_entry *ce)
 266{
 267        unsigned ce_mode = ntohl(ce->ce_mode);
 268        if (S_ISREG(ce_mode))
 269                return DT_REG;
 270        else if (S_ISDIR(ce_mode) || S_ISGITLINK(ce_mode))
 271                return DT_DIR;
 272        else if (S_ISLNK(ce_mode))
 273                return DT_LNK;
 274        else
 275                return DT_UNKNOWN;
 276}
 277static inline unsigned int canon_mode(unsigned int mode)
 278{
 279        if (S_ISREG(mode))
 280                return S_IFREG | ce_permissions(mode);
 281        if (S_ISLNK(mode))
 282                return S_IFLNK;
 283        if (S_ISDIR(mode))
 284                return S_IFDIR;
 285        return S_IFGITLINK;
 286}
 287
 288#define cache_entry_size(len) (offsetof(struct cache_entry,name) + (len) + 1)
 289
 290#define SOMETHING_CHANGED       (1 << 0) /* unclassified changes go here */
 291#define CE_ENTRY_CHANGED        (1 << 1)
 292#define CE_ENTRY_REMOVED        (1 << 2)
 293#define CE_ENTRY_ADDED          (1 << 3)
 294#define RESOLVE_UNDO_CHANGED    (1 << 4)
 295#define CACHE_TREE_CHANGED      (1 << 5)
 296#define SPLIT_INDEX_ORDERED     (1 << 6)
 297
 298struct split_index;
 299struct index_state {
 300        struct cache_entry **cache;
 301        unsigned int version;
 302        unsigned int cache_nr, cache_alloc, cache_changed;
 303        struct string_list *resolve_undo;
 304        struct cache_tree *cache_tree;
 305        struct split_index *split_index;
 306        struct cache_time timestamp;
 307        unsigned name_hash_initialized : 1,
 308                 initialized : 1;
 309        struct hashmap name_hash;
 310        struct hashmap dir_hash;
 311        unsigned char sha1[20];
 312};
 313
 314extern struct index_state the_index;
 315
 316/* Name hashing */
 317extern void add_name_hash(struct index_state *istate, struct cache_entry *ce);
 318extern void remove_name_hash(struct index_state *istate, struct cache_entry *ce);
 319extern void free_name_hash(struct index_state *istate);
 320
 321
 322#ifndef NO_THE_INDEX_COMPATIBILITY_MACROS
 323#define active_cache (the_index.cache)
 324#define active_nr (the_index.cache_nr)
 325#define active_alloc (the_index.cache_alloc)
 326#define active_cache_changed (the_index.cache_changed)
 327#define active_cache_tree (the_index.cache_tree)
 328
 329#define read_cache() read_index(&the_index)
 330#define read_cache_from(path) read_index_from(&the_index, (path))
 331#define read_cache_preload(pathspec) read_index_preload(&the_index, (pathspec))
 332#define is_cache_unborn() is_index_unborn(&the_index)
 333#define read_cache_unmerged() read_index_unmerged(&the_index)
 334#define discard_cache() discard_index(&the_index)
 335#define unmerged_cache() unmerged_index(&the_index)
 336#define cache_name_pos(name, namelen) index_name_pos(&the_index,(name),(namelen))
 337#define add_cache_entry(ce, option) add_index_entry(&the_index, (ce), (option))
 338#define rename_cache_entry_at(pos, new_name) rename_index_entry_at(&the_index, (pos), (new_name))
 339#define remove_cache_entry_at(pos) remove_index_entry_at(&the_index, (pos))
 340#define remove_file_from_cache(path) remove_file_from_index(&the_index, (path))
 341#define add_to_cache(path, st, flags) add_to_index(&the_index, (path), (st), (flags))
 342#define add_file_to_cache(path, flags) add_file_to_index(&the_index, (path), (flags))
 343#define refresh_cache(flags) refresh_index(&the_index, (flags), NULL, NULL, NULL)
 344#define ce_match_stat(ce, st, options) ie_match_stat(&the_index, (ce), (st), (options))
 345#define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
 346#define cache_dir_exists(name, namelen) index_dir_exists(&the_index, (name), (namelen))
 347#define cache_file_exists(name, namelen, igncase) index_file_exists(&the_index, (name), (namelen), (igncase))
 348#define cache_name_is_other(name, namelen) index_name_is_other(&the_index, (name), (namelen))
 349#define resolve_undo_clear() resolve_undo_clear_index(&the_index)
 350#define unmerge_cache_entry_at(at) unmerge_index_entry_at(&the_index, at)
 351#define unmerge_cache(pathspec) unmerge_index(&the_index, pathspec)
 352#define read_blob_data_from_cache(path, sz) read_blob_data_from_index(&the_index, (path), (sz))
 353#endif
 354
 355enum object_type {
 356        OBJ_BAD = -1,
 357        OBJ_NONE = 0,
 358        OBJ_COMMIT = 1,
 359        OBJ_TREE = 2,
 360        OBJ_BLOB = 3,
 361        OBJ_TAG = 4,
 362        /* 5 for future expansion */
 363        OBJ_OFS_DELTA = 6,
 364        OBJ_REF_DELTA = 7,
 365        OBJ_ANY,
 366        OBJ_MAX
 367};
 368
 369static inline enum object_type object_type(unsigned int mode)
 370{
 371        return S_ISDIR(mode) ? OBJ_TREE :
 372                S_ISGITLINK(mode) ? OBJ_COMMIT :
 373                OBJ_BLOB;
 374}
 375
 376/* Double-check local_repo_env below if you add to this list. */
 377#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 378#define GIT_NAMESPACE_ENVIRONMENT "GIT_NAMESPACE"
 379#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
 380#define GIT_PREFIX_ENVIRONMENT "GIT_PREFIX"
 381#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 382#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 383#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 384#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 385#define GIT_SHALLOW_FILE_ENVIRONMENT "GIT_SHALLOW_FILE"
 386#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
 387#define CONFIG_ENVIRONMENT "GIT_CONFIG"
 388#define CONFIG_DATA_ENVIRONMENT "GIT_CONFIG_PARAMETERS"
 389#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 390#define CEILING_DIRECTORIES_ENVIRONMENT "GIT_CEILING_DIRECTORIES"
 391#define NO_REPLACE_OBJECTS_ENVIRONMENT "GIT_NO_REPLACE_OBJECTS"
 392#define GITATTRIBUTES_FILE ".gitattributes"
 393#define INFOATTRIBUTES_FILE "info/attributes"
 394#define ATTRIBUTE_MACRO_PREFIX "[attr]"
 395#define GIT_NOTES_REF_ENVIRONMENT "GIT_NOTES_REF"
 396#define GIT_NOTES_DEFAULT_REF "refs/notes/commits"
 397#define GIT_NOTES_DISPLAY_REF_ENVIRONMENT "GIT_NOTES_DISPLAY_REF"
 398#define GIT_NOTES_REWRITE_REF_ENVIRONMENT "GIT_NOTES_REWRITE_REF"
 399#define GIT_NOTES_REWRITE_MODE_ENVIRONMENT "GIT_NOTES_REWRITE_MODE"
 400#define GIT_LITERAL_PATHSPECS_ENVIRONMENT "GIT_LITERAL_PATHSPECS"
 401#define GIT_GLOB_PATHSPECS_ENVIRONMENT "GIT_GLOB_PATHSPECS"
 402#define GIT_NOGLOB_PATHSPECS_ENVIRONMENT "GIT_NOGLOB_PATHSPECS"
 403#define GIT_ICASE_PATHSPECS_ENVIRONMENT "GIT_ICASE_PATHSPECS"
 404
 405/*
 406 * This environment variable is expected to contain a boolean indicating
 407 * whether we should or should not treat:
 408 *
 409 *   GIT_DIR=foo.git git ...
 410 *
 411 * as if GIT_WORK_TREE=. was given. It's not expected that users will make use
 412 * of this, but we use it internally to communicate to sub-processes that we
 413 * are in a bare repo. If not set, defaults to true.
 414 */
 415#define GIT_IMPLICIT_WORK_TREE_ENVIRONMENT "GIT_IMPLICIT_WORK_TREE"
 416
 417/*
 418 * Repository-local GIT_* environment variables; these will be cleared
 419 * when git spawns a sub-process that runs inside another repository.
 420 * The array is NULL-terminated, which makes it easy to pass in the "env"
 421 * parameter of a run-command invocation, or to do a simple walk.
 422 */
 423extern const char * const local_repo_env[];
 424
 425extern int is_bare_repository_cfg;
 426extern int is_bare_repository(void);
 427extern int is_inside_git_dir(void);
 428extern char *git_work_tree_cfg;
 429extern int is_inside_work_tree(void);
 430extern const char *get_git_dir(void);
 431extern int is_git_directory(const char *path);
 432extern char *get_object_directory(void);
 433extern char *get_index_file(void);
 434extern char *get_graft_file(void);
 435extern int set_git_dir(const char *path);
 436extern const char *get_git_namespace(void);
 437extern const char *strip_namespace(const char *namespaced_ref);
 438extern const char *get_git_work_tree(void);
 439extern const char *read_gitfile(const char *path);
 440extern const char *resolve_gitdir(const char *suspect);
 441extern void set_git_work_tree(const char *tree);
 442
 443#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 444
 445extern const char **get_pathspec(const char *prefix, const char **pathspec);
 446extern void setup_work_tree(void);
 447extern const char *setup_git_directory_gently(int *);
 448extern const char *setup_git_directory(void);
 449extern char *prefix_path(const char *prefix, int len, const char *path);
 450extern char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
 451extern const char *prefix_filename(const char *prefix, int len, const char *path);
 452extern int check_filename(const char *prefix, const char *name);
 453extern void verify_filename(const char *prefix,
 454                            const char *name,
 455                            int diagnose_misspelt_rev);
 456extern void verify_non_filename(const char *prefix, const char *name);
 457extern int path_inside_repo(const char *prefix, const char *path);
 458
 459#define INIT_DB_QUIET 0x0001
 460
 461extern int set_git_dir_init(const char *git_dir, const char *real_git_dir, int);
 462extern int init_db(const char *template_dir, unsigned int flags);
 463
 464extern void sanitize_stdfds(void);
 465extern int daemonize(void);
 466
 467#define alloc_nr(x) (((x)+16)*3/2)
 468
 469/*
 470 * Realloc the buffer pointed at by variable 'x' so that it can hold
 471 * at least 'nr' entries; the number of entries currently allocated
 472 * is 'alloc', using the standard growing factor alloc_nr() macro.
 473 *
 474 * DO NOT USE any expression with side-effect for 'x', 'nr', or 'alloc'.
 475 */
 476#define ALLOC_GROW(x, nr, alloc) \
 477        do { \
 478                if ((nr) > alloc) { \
 479                        if (alloc_nr(alloc) < (nr)) \
 480                                alloc = (nr); \
 481                        else \
 482                                alloc = alloc_nr(alloc); \
 483                        x = xrealloc((x), alloc * sizeof(*(x))); \
 484                } \
 485        } while (0)
 486
 487/* Initialize and use the cache information */
 488struct lock_file;
 489extern int read_index(struct index_state *);
 490extern int read_index_preload(struct index_state *, const struct pathspec *pathspec);
 491extern int do_read_index(struct index_state *istate, const char *path,
 492                         int must_exist); /* for testting only! */
 493extern int read_index_from(struct index_state *, const char *path);
 494extern int is_index_unborn(struct index_state *);
 495extern int read_index_unmerged(struct index_state *);
 496#define COMMIT_LOCK             (1 << 0)
 497#define CLOSE_LOCK              (1 << 1)
 498extern int write_locked_index(struct index_state *, struct lock_file *lock, unsigned flags);
 499extern int discard_index(struct index_state *);
 500extern int unmerged_index(const struct index_state *);
 501extern int verify_path(const char *path);
 502extern struct cache_entry *index_dir_exists(struct index_state *istate, const char *name, int namelen);
 503extern struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 504extern int index_name_pos(const struct index_state *, const char *name, int namelen);
 505#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 506#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 507#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 508#define ADD_CACHE_JUST_APPEND 8         /* Append only; tree.c::read_tree() */
 509#define ADD_CACHE_NEW_ONLY 16           /* Do not replace existing ones */
 510#define ADD_CACHE_KEEP_CACHE_TREE 32    /* Do not invalidate cache-tree */
 511extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
 512extern void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
 513extern int remove_index_entry_at(struct index_state *, int pos);
 514extern void remove_marked_cache_entries(struct index_state *istate);
 515extern int remove_file_from_index(struct index_state *, const char *path);
 516#define ADD_CACHE_VERBOSE 1
 517#define ADD_CACHE_PRETEND 2
 518#define ADD_CACHE_IGNORE_ERRORS 4
 519#define ADD_CACHE_IGNORE_REMOVAL 8
 520#define ADD_CACHE_INTENT 16
 521extern int add_to_index(struct index_state *, const char *path, struct stat *, int flags);
 522extern int add_file_to_index(struct index_state *, const char *path, int flags);
 523extern struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, unsigned int refresh_options);
 524extern int ce_same_name(const struct cache_entry *a, const struct cache_entry *b);
 525extern void set_object_name_for_intent_to_add_entry(struct cache_entry *ce);
 526extern int index_name_is_other(const struct index_state *, const char *, int);
 527extern void *read_blob_data_from_index(struct index_state *, const char *, unsigned long *);
 528
 529/* do stat comparison even if CE_VALID is true */
 530#define CE_MATCH_IGNORE_VALID           01
 531/* do not check the contents but report dirty on racily-clean entries */
 532#define CE_MATCH_RACY_IS_DIRTY          02
 533/* do stat comparison even if CE_SKIP_WORKTREE is true */
 534#define CE_MATCH_IGNORE_SKIP_WORKTREE   04
 535/* ignore non-existent files during stat update  */
 536#define CE_MATCH_IGNORE_MISSING         0x08
 537/* enable stat refresh */
 538#define CE_MATCH_REFRESH                0x10
 539extern int ie_match_stat(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 540extern int ie_modified(const struct index_state *, const struct cache_entry *, struct stat *, unsigned int);
 541
 542#define HASH_WRITE_OBJECT 1
 543#define HASH_FORMAT_CHECK 2
 544extern int index_fd(unsigned char *sha1, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
 545extern int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags);
 546
 547/*
 548 * Record to sd the data from st that we use to check whether a file
 549 * might have changed.
 550 */
 551extern void fill_stat_data(struct stat_data *sd, struct stat *st);
 552
 553/*
 554 * Return 0 if st is consistent with a file not having been changed
 555 * since sd was filled.  If there are differences, return a
 556 * combination of MTIME_CHANGED, CTIME_CHANGED, OWNER_CHANGED,
 557 * INODE_CHANGED, and DATA_CHANGED.
 558 */
 559extern int match_stat_data(const struct stat_data *sd, struct stat *st);
 560
 561extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 562
 563#define REFRESH_REALLY          0x0001  /* ignore_valid */
 564#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 565#define REFRESH_QUIET           0x0004  /* be quiet about it */
 566#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 567#define REFRESH_IGNORE_SUBMODULES       0x0010  /* ignore submodules */
 568#define REFRESH_IN_PORCELAIN    0x0020  /* user friendly output, not "needs update" */
 569extern int refresh_index(struct index_state *, unsigned int flags, const struct pathspec *pathspec, char *seen, const char *header_msg);
 570
 571struct lock_file {
 572        struct lock_file *next;
 573        int fd;
 574        pid_t owner;
 575        char on_list;
 576        char filename[PATH_MAX];
 577};
 578#define LOCK_DIE_ON_ERROR 1
 579#define LOCK_NODEREF 2
 580extern int unable_to_lock_error(const char *path, int err);
 581extern NORETURN void unable_to_lock_index_die(const char *path, int err);
 582extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 583extern int hold_lock_file_for_append(struct lock_file *, const char *path, int);
 584extern int commit_lock_file(struct lock_file *);
 585extern void update_index_if_able(struct index_state *, struct lock_file *);
 586
 587extern int hold_locked_index(struct lock_file *, int);
 588extern void set_alternate_index_output(const char *);
 589extern int close_lock_file(struct lock_file *);
 590extern void rollback_lock_file(struct lock_file *);
 591extern int delete_ref(const char *, const unsigned char *sha1, int delopt);
 592
 593/* Environment bits from configuration mechanism */
 594extern int trust_executable_bit;
 595extern int trust_ctime;
 596extern int check_stat;
 597extern int quote_path_fully;
 598extern int has_symlinks;
 599extern int minimum_abbrev, default_abbrev;
 600extern int ignore_case;
 601extern int assume_unchanged;
 602extern int prefer_symlink_refs;
 603extern int log_all_ref_updates;
 604extern int warn_ambiguous_refs;
 605extern int warn_on_object_refname_ambiguity;
 606extern int shared_repository;
 607extern const char *apply_default_whitespace;
 608extern const char *apply_default_ignorewhitespace;
 609extern const char *git_attributes_file;
 610extern int zlib_compression_level;
 611extern int core_compression_level;
 612extern int core_compression_seen;
 613extern size_t packed_git_window_size;
 614extern size_t packed_git_limit;
 615extern size_t delta_base_cache_limit;
 616extern unsigned long big_file_threshold;
 617extern unsigned long pack_size_limit_cfg;
 618
 619/*
 620 * Do replace refs need to be checked this run?  This variable is
 621 * initialized to true unless --no-replace-object is used or
 622 * $GIT_NO_REPLACE_OBJECTS is set, but is set to false by some
 623 * commands that do not want replace references to be active.  As an
 624 * optimization it is also set to false if replace references have
 625 * been sought but there were none.
 626 */
 627extern int check_replace_refs;
 628
 629extern int fsync_object_files;
 630extern int core_preload_index;
 631extern int core_apply_sparse_checkout;
 632extern int precomposed_unicode;
 633
 634/*
 635 * The character that begins a commented line in user-editable file
 636 * that is subject to stripspace.
 637 */
 638extern char comment_line_char;
 639extern int auto_comment_line_char;
 640
 641enum branch_track {
 642        BRANCH_TRACK_UNSPECIFIED = -1,
 643        BRANCH_TRACK_NEVER = 0,
 644        BRANCH_TRACK_REMOTE,
 645        BRANCH_TRACK_ALWAYS,
 646        BRANCH_TRACK_EXPLICIT,
 647        BRANCH_TRACK_OVERRIDE
 648};
 649
 650enum rebase_setup_type {
 651        AUTOREBASE_NEVER = 0,
 652        AUTOREBASE_LOCAL,
 653        AUTOREBASE_REMOTE,
 654        AUTOREBASE_ALWAYS
 655};
 656
 657enum push_default_type {
 658        PUSH_DEFAULT_NOTHING = 0,
 659        PUSH_DEFAULT_MATCHING,
 660        PUSH_DEFAULT_SIMPLE,
 661        PUSH_DEFAULT_UPSTREAM,
 662        PUSH_DEFAULT_CURRENT,
 663        PUSH_DEFAULT_UNSPECIFIED
 664};
 665
 666extern enum branch_track git_branch_track;
 667extern enum rebase_setup_type autorebase;
 668extern enum push_default_type push_default;
 669
 670enum object_creation_mode {
 671        OBJECT_CREATION_USES_HARDLINKS = 0,
 672        OBJECT_CREATION_USES_RENAMES = 1
 673};
 674
 675extern enum object_creation_mode object_creation_mode;
 676
 677extern char *notes_ref_name;
 678
 679extern int grafts_replace_parents;
 680
 681#define GIT_REPO_VERSION 0
 682extern int repository_format_version;
 683extern int check_repository_format(void);
 684
 685#define MTIME_CHANGED   0x0001
 686#define CTIME_CHANGED   0x0002
 687#define OWNER_CHANGED   0x0004
 688#define MODE_CHANGED    0x0008
 689#define INODE_CHANGED   0x0010
 690#define DATA_CHANGED    0x0020
 691#define TYPE_CHANGED    0x0040
 692
 693extern char *mksnpath(char *buf, size_t n, const char *fmt, ...)
 694        __attribute__((format (printf, 3, 4)));
 695extern char *git_snpath(char *buf, size_t n, const char *fmt, ...)
 696        __attribute__((format (printf, 3, 4)));
 697extern char *git_pathdup(const char *fmt, ...)
 698        __attribute__((format (printf, 1, 2)));
 699extern char *mkpathdup(const char *fmt, ...)
 700        __attribute__((format (printf, 1, 2)));
 701
 702/* Return a statically allocated filename matching the sha1 signature */
 703extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 704extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 705extern char *git_path_submodule(const char *path, const char *fmt, ...)
 706        __attribute__((format (printf, 2, 3)));
 707
 708/*
 709 * Return the name of the file in the local object database that would
 710 * be used to store a loose object with the specified sha1.  The
 711 * return value is a pointer to a statically allocated buffer that is
 712 * overwritten each time the function is called.
 713 */
 714extern const char *sha1_file_name(const unsigned char *sha1);
 715
 716/*
 717 * Return the name of the (local) packfile with the specified sha1 in
 718 * its name.  The return value is a pointer to memory that is
 719 * overwritten each time this function is called.
 720 */
 721extern char *sha1_pack_name(const unsigned char *sha1);
 722
 723/*
 724 * Return the name of the (local) pack index file with the specified
 725 * sha1 in its name.  The return value is a pointer to memory that is
 726 * overwritten each time this function is called.
 727 */
 728extern char *sha1_pack_index_name(const unsigned char *sha1);
 729
 730extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 731extern const unsigned char null_sha1[20];
 732
 733static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 734{
 735        int i;
 736
 737        for (i = 0; i < 20; i++, sha1++, sha2++) {
 738                if (*sha1 != *sha2)
 739                        return *sha1 - *sha2;
 740        }
 741
 742        return 0;
 743}
 744
 745static inline int is_null_sha1(const unsigned char *sha1)
 746{
 747        return !hashcmp(sha1, null_sha1);
 748}
 749
 750static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
 751{
 752        memcpy(sha_dst, sha_src, 20);
 753}
 754static inline void hashclr(unsigned char *hash)
 755{
 756        memset(hash, 0, 20);
 757}
 758
 759#define EMPTY_TREE_SHA1_HEX \
 760        "4b825dc642cb6eb9a060e54bf8d69288fbee4904"
 761#define EMPTY_TREE_SHA1_BIN_LITERAL \
 762         "\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
 763         "\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
 764#define EMPTY_TREE_SHA1_BIN \
 765         ((const unsigned char *) EMPTY_TREE_SHA1_BIN_LITERAL)
 766
 767#define EMPTY_BLOB_SHA1_HEX \
 768        "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"
 769#define EMPTY_BLOB_SHA1_BIN_LITERAL \
 770        "\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
 771        "\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
 772#define EMPTY_BLOB_SHA1_BIN \
 773        ((const unsigned char *) EMPTY_BLOB_SHA1_BIN_LITERAL)
 774
 775static inline int is_empty_blob_sha1(const unsigned char *sha1)
 776{
 777        return !hashcmp(sha1, EMPTY_BLOB_SHA1_BIN);
 778}
 779
 780int git_mkstemp(char *path, size_t n, const char *template);
 781
 782int git_mkstemps(char *path, size_t n, const char *template, int suffix_len);
 783
 784/* set default permissions by passing mode arguments to open(2) */
 785int git_mkstemps_mode(char *pattern, int suffix_len, int mode);
 786int git_mkstemp_mode(char *pattern, int mode);
 787
 788/*
 789 * NOTE NOTE NOTE!!
 790 *
 791 * PERM_UMASK, OLD_PERM_GROUP and OLD_PERM_EVERYBODY enumerations must
 792 * not be changed. Old repositories have core.sharedrepository written in
 793 * numeric format, and therefore these values are preserved for compatibility
 794 * reasons.
 795 */
 796enum sharedrepo {
 797        PERM_UMASK          = 0,
 798        OLD_PERM_GROUP      = 1,
 799        OLD_PERM_EVERYBODY  = 2,
 800        PERM_GROUP          = 0660,
 801        PERM_EVERYBODY      = 0664
 802};
 803int git_config_perm(const char *var, const char *value);
 804int adjust_shared_perm(const char *path);
 805
 806/*
 807 * Create the directory containing the named path, using care to be
 808 * somewhat safe against races.  Return one of the scld_error values
 809 * to indicate success/failure.
 810 *
 811 * SCLD_VANISHED indicates that one of the ancestor directories of the
 812 * path existed at one point during the function call and then
 813 * suddenly vanished, probably because another process pruned the
 814 * directory while we were working.  To be robust against this kind of
 815 * race, callers might want to try invoking the function again when it
 816 * returns SCLD_VANISHED.
 817 */
 818enum scld_error {
 819        SCLD_OK = 0,
 820        SCLD_FAILED = -1,
 821        SCLD_PERMS = -2,
 822        SCLD_EXISTS = -3,
 823        SCLD_VANISHED = -4
 824};
 825enum scld_error safe_create_leading_directories(char *path);
 826enum scld_error safe_create_leading_directories_const(const char *path);
 827
 828int mkdir_in_gitdir(const char *path);
 829extern void home_config_paths(char **global, char **xdg, char *file);
 830extern char *expand_user_path(const char *path);
 831const char *enter_repo(const char *path, int strict);
 832static inline int is_absolute_path(const char *path)
 833{
 834        return is_dir_sep(path[0]) || has_dos_drive_prefix(path);
 835}
 836int is_directory(const char *);
 837const char *real_path(const char *path);
 838const char *real_path_if_valid(const char *path);
 839const char *absolute_path(const char *path);
 840const char *remove_leading_path(const char *in, const char *prefix);
 841const char *relative_path(const char *in, const char *prefix, struct strbuf *sb);
 842int normalize_path_copy_len(char *dst, const char *src, int *prefix_len);
 843int normalize_path_copy(char *dst, const char *src);
 844int longest_ancestor_length(const char *path, struct string_list *prefixes);
 845char *strip_path_suffix(const char *path, const char *suffix);
 846int daemon_avoid_alias(const char *path);
 847
 848/* object replacement */
 849#define LOOKUP_REPLACE_OBJECT 1
 850extern void *read_sha1_file_extended(const unsigned char *sha1, enum object_type *type, unsigned long *size, unsigned flag);
 851static inline void *read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
 852{
 853        return read_sha1_file_extended(sha1, type, size, LOOKUP_REPLACE_OBJECT);
 854}
 855
 856/*
 857 * This internal function is only declared here for the benefit of
 858 * lookup_replace_object().  Please do not call it directly.
 859 */
 860extern const unsigned char *do_lookup_replace_object(const unsigned char *sha1);
 861
 862/*
 863 * If object sha1 should be replaced, return the replacement object's
 864 * name (replaced recursively, if necessary).  The return value is
 865 * either sha1 or a pointer to a permanently-allocated value.  When
 866 * object replacement is suppressed, always return sha1.
 867 */
 868static inline const unsigned char *lookup_replace_object(const unsigned char *sha1)
 869{
 870        if (!check_replace_refs)
 871                return sha1;
 872        return do_lookup_replace_object(sha1);
 873}
 874
 875static inline const unsigned char *lookup_replace_object_extended(const unsigned char *sha1, unsigned flag)
 876{
 877        if (!(flag & LOOKUP_REPLACE_OBJECT))
 878                return sha1;
 879        return lookup_replace_object(sha1);
 880}
 881
 882/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 883extern int sha1_object_info(const unsigned char *, unsigned long *);
 884extern int hash_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1);
 885extern int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 886extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
 887extern int force_object_loose(const unsigned char *sha1, time_t mtime);
 888extern int git_open_noatime(const char *name);
 889extern void *map_sha1_file(const unsigned char *sha1, unsigned long *size);
 890extern int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz);
 891extern int parse_sha1_header(const char *hdr, unsigned long *sizep);
 892
 893/* global flag to enable extra checks when accessing packed objects */
 894extern int do_check_packed_object_crc;
 895
 896extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 897
 898extern int move_temp_to_file(const char *tmpfile, const char *filename);
 899
 900extern int has_sha1_pack(const unsigned char *sha1);
 901
 902/*
 903 * Return true iff we have an object named sha1, whether local or in
 904 * an alternate object database, and whether packed or loose.  This
 905 * function does not respect replace references.
 906 */
 907extern int has_sha1_file(const unsigned char *sha1);
 908
 909/*
 910 * Return true iff an alternate object database has a loose object
 911 * with the specified name.  This function does not respect replace
 912 * references.
 913 */
 914extern int has_loose_object_nonlocal(const unsigned char *sha1);
 915
 916extern int has_pack_index(const unsigned char *sha1);
 917
 918extern void assert_sha1_type(const unsigned char *sha1, enum object_type expect);
 919
 920extern const signed char hexval_table[256];
 921static inline unsigned int hexval(unsigned char c)
 922{
 923        return hexval_table[c];
 924}
 925
 926/* Convert to/from hex/sha1 representation */
 927#define MINIMUM_ABBREV minimum_abbrev
 928#define DEFAULT_ABBREV default_abbrev
 929
 930struct object_context {
 931        unsigned char tree[20];
 932        char path[PATH_MAX];
 933        unsigned mode;
 934};
 935
 936#define GET_SHA1_QUIETLY        01
 937#define GET_SHA1_COMMIT         02
 938#define GET_SHA1_COMMITTISH     04
 939#define GET_SHA1_TREE          010
 940#define GET_SHA1_TREEISH       020
 941#define GET_SHA1_BLOB          040
 942#define GET_SHA1_ONLY_TO_DIE 04000
 943
 944extern int get_sha1(const char *str, unsigned char *sha1);
 945extern int get_sha1_commit(const char *str, unsigned char *sha1);
 946extern int get_sha1_committish(const char *str, unsigned char *sha1);
 947extern int get_sha1_tree(const char *str, unsigned char *sha1);
 948extern int get_sha1_treeish(const char *str, unsigned char *sha1);
 949extern int get_sha1_blob(const char *str, unsigned char *sha1);
 950extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
 951extern int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc);
 952
 953typedef int each_abbrev_fn(const unsigned char *sha1, void *);
 954extern int for_each_abbrev(const char *prefix, each_abbrev_fn, void *);
 955
 956/*
 957 * Try to read a SHA1 in hexadecimal format from the 40 characters
 958 * starting at hex.  Write the 20-byte result to sha1 in binary form.
 959 * Return 0 on success.  Reading stops if a NUL is encountered in the
 960 * input, so it is safe to pass this function an arbitrary
 961 * null-terminated string.
 962 */
 963extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 964
 965extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 966extern int read_ref_full(const char *refname, unsigned char *sha1,
 967                         int reading, int *flags);
 968extern int read_ref(const char *refname, unsigned char *sha1);
 969
 970/*
 971 * Resolve a reference, recursively following symbolic refererences.
 972 *
 973 * Store the referred-to object's name in sha1 and return the name of
 974 * the non-symbolic reference that ultimately pointed at it.  The
 975 * return value, if not NULL, is a pointer into either a static buffer
 976 * or the input ref.
 977 *
 978 * If the reference cannot be resolved to an object, the behavior
 979 * depends on the "reading" argument:
 980 *
 981 * - If reading is set, return NULL.
 982 *
 983 * - If reading is not set, clear sha1 and return the name of the last
 984 *   reference name in the chain, which will either be a non-symbolic
 985 *   reference or an undefined reference.  If this is a prelude to
 986 *   "writing" to the ref, the return value is the name of the ref
 987 *   that will actually be created or changed.
 988 *
 989 * If flag is non-NULL, set the value that it points to the
 990 * combination of REF_ISPACKED (if the reference was found among the
 991 * packed references) and REF_ISSYMREF (if the initial reference was a
 992 * symbolic reference).
 993 *
 994 * If ref is not a properly-formatted, normalized reference, return
 995 * NULL.  If more than MAXDEPTH recursive symbolic lookups are needed,
 996 * give up and return NULL.
 997 *
 998 * errno is sometimes set on errors, but not always.
 999 */
1000extern const char *resolve_ref_unsafe(const char *ref, unsigned char *sha1, int reading, int *flag);
1001extern char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag);
1002
1003extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
1004extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
1005extern int interpret_branch_name(const char *str, int len, struct strbuf *);
1006extern int get_sha1_mb(const char *str, unsigned char *sha1);
1007
1008/*
1009 * Return true iff abbrev_name is a possible abbreviation for
1010 * full_name according to the rules defined by ref_rev_parse_rules in
1011 * refs.c.
1012 */
1013extern int refname_match(const char *abbrev_name, const char *full_name);
1014
1015extern int create_symref(const char *ref, const char *refs_heads_master, const char *logmsg);
1016extern int validate_headref(const char *ref);
1017
1018extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
1019extern int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
1020extern int name_compare(const char *name1, size_t len1, const char *name2, size_t len2);
1021extern int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2);
1022
1023extern void *read_object_with_reference(const unsigned char *sha1,
1024                                        const char *required_type,
1025                                        unsigned long *size,
1026                                        unsigned char *sha1_ret);
1027
1028extern struct object *peel_to_type(const char *name, int namelen,
1029                                   struct object *o, enum object_type);
1030
1031enum date_mode {
1032        DATE_NORMAL = 0,
1033        DATE_RELATIVE,
1034        DATE_SHORT,
1035        DATE_LOCAL,
1036        DATE_ISO8601,
1037        DATE_RFC2822,
1038        DATE_RAW
1039};
1040
1041const char *show_date(unsigned long time, int timezone, enum date_mode mode);
1042void show_date_relative(unsigned long time, int tz, const struct timeval *now,
1043                        struct strbuf *timebuf);
1044int parse_date(const char *date, char *buf, int bufsize);
1045int parse_date_basic(const char *date, unsigned long *timestamp, int *offset);
1046int parse_expiry_date(const char *date, unsigned long *timestamp);
1047void datestamp(char *buf, int bufsize);
1048#define approxidate(s) approxidate_careful((s), NULL)
1049unsigned long approxidate_careful(const char *, int *);
1050unsigned long approxidate_relative(const char *date, const struct timeval *now);
1051enum date_mode parse_date_format(const char *format);
1052int date_overflows(unsigned long date);
1053
1054#define IDENT_STRICT           1
1055#define IDENT_NO_DATE          2
1056#define IDENT_NO_NAME          4
1057extern const char *git_author_info(int);
1058extern const char *git_committer_info(int);
1059extern const char *fmt_ident(const char *name, const char *email, const char *date_str, int);
1060extern const char *fmt_name(const char *name, const char *email);
1061extern const char *ident_default_email(void);
1062extern const char *git_editor(void);
1063extern const char *git_pager(int stdout_is_tty);
1064extern int git_ident_config(const char *, const char *, void *);
1065
1066struct ident_split {
1067        const char *name_begin;
1068        const char *name_end;
1069        const char *mail_begin;
1070        const char *mail_end;
1071        const char *date_begin;
1072        const char *date_end;
1073        const char *tz_begin;
1074        const char *tz_end;
1075};
1076/*
1077 * Signals an success with 0, but time part of the result may be NULL
1078 * if the input lacks timestamp and zone
1079 */
1080extern int split_ident_line(struct ident_split *, const char *, int);
1081
1082/*
1083 * Like show_date, but pull the timestamp and tz parameters from
1084 * the ident_split. It will also sanity-check the values and produce
1085 * a well-known sentinel date if they appear bogus.
1086 */
1087const char *show_ident_date(const struct ident_split *id, enum date_mode mode);
1088
1089/*
1090 * Compare split idents for equality or strict ordering. Note that we
1091 * compare only the ident part of the line, ignoring any timestamp.
1092 *
1093 * Because there are two fields, we must choose one as the primary key; we
1094 * currently arbitrarily pick the email.
1095 */
1096extern int ident_cmp(const struct ident_split *, const struct ident_split *);
1097
1098struct checkout {
1099        struct index_state *istate;
1100        const char *base_dir;
1101        int base_dir_len;
1102        unsigned force:1,
1103                 quiet:1,
1104                 not_new:1,
1105                 refresh_cache:1;
1106};
1107
1108#define TEMPORARY_FILENAME_LENGTH 25
1109extern int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath);
1110
1111struct cache_def {
1112        struct strbuf path;
1113        int flags;
1114        int track_flags;
1115        int prefix_len_stat_func;
1116};
1117#define CACHE_DEF_INIT { STRBUF_INIT, 0, 0, 0 }
1118static inline void cache_def_free(struct cache_def *cache)
1119{
1120        strbuf_release(&cache->path);
1121}
1122
1123extern int has_symlink_leading_path(const char *name, int len);
1124extern int threaded_has_symlink_leading_path(struct cache_def *, const char *, int);
1125extern int check_leading_path(const char *name, int len);
1126extern int has_dirs_only_path(const char *name, int len, int prefix_len);
1127extern void schedule_dir_for_removal(const char *name, int len);
1128extern void remove_scheduled_dirs(void);
1129
1130extern struct alternate_object_database {
1131        struct alternate_object_database *next;
1132        char *name;
1133        char base[FLEX_ARRAY]; /* more */
1134} *alt_odb_list;
1135extern void prepare_alt_odb(void);
1136extern void read_info_alternates(const char * relative_base, int depth);
1137extern void add_to_alternates_file(const char *reference);
1138typedef int alt_odb_fn(struct alternate_object_database *, void *);
1139extern void foreach_alt_odb(alt_odb_fn, void*);
1140
1141struct pack_window {
1142        struct pack_window *next;
1143        unsigned char *base;
1144        off_t offset;
1145        size_t len;
1146        unsigned int last_used;
1147        unsigned int inuse_cnt;
1148};
1149
1150extern struct packed_git {
1151        struct packed_git *next;
1152        struct pack_window *windows;
1153        off_t pack_size;
1154        const void *index_data;
1155        size_t index_size;
1156        uint32_t num_objects;
1157        uint32_t num_bad_objects;
1158        unsigned char *bad_object_sha1;
1159        int index_version;
1160        time_t mtime;
1161        int pack_fd;
1162        unsigned pack_local:1,
1163                 pack_keep:1,
1164                 do_not_close:1;
1165        unsigned char sha1[20];
1166        /* something like ".git/objects/pack/xxxxx.pack" */
1167        char pack_name[FLEX_ARRAY]; /* more */
1168} *packed_git;
1169
1170struct pack_entry {
1171        off_t offset;
1172        unsigned char sha1[20];
1173        struct packed_git *p;
1174};
1175
1176extern struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
1177
1178/* A hook for count-objects to report invalid files in pack directory */
1179extern void (*report_garbage)(const char *desc, const char *path);
1180
1181extern void prepare_packed_git(void);
1182extern void reprepare_packed_git(void);
1183extern void install_packed_git(struct packed_git *pack);
1184
1185extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
1186                                         struct packed_git *packs);
1187
1188extern void pack_report(void);
1189
1190/*
1191 * mmap the index file for the specified packfile (if it is not
1192 * already mmapped).  Return 0 on success.
1193 */
1194extern int open_pack_index(struct packed_git *);
1195
1196/*
1197 * munmap the index file for the specified packfile (if it is
1198 * currently mmapped).
1199 */
1200extern void close_pack_index(struct packed_git *);
1201
1202extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
1203extern void close_pack_windows(struct packed_git *);
1204extern void unuse_pack(struct pack_window **);
1205extern void free_pack_by_name(const char *);
1206extern void clear_delta_base_cache(void);
1207extern struct packed_git *add_packed_git(const char *, int, int);
1208
1209/*
1210 * Return the SHA-1 of the nth object within the specified packfile.
1211 * Open the index if it is not already open.  The return value points
1212 * at the SHA-1 within the mmapped index.  Return NULL if there is an
1213 * error.
1214 */
1215extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
1216
1217/*
1218 * Return the offset of the nth object within the specified packfile.
1219 * The index must already be opened.
1220 */
1221extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
1222
1223/*
1224 * If the object named sha1 is present in the specified packfile,
1225 * return its offset within the packfile; otherwise, return 0.
1226 */
1227extern off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
1228
1229extern int is_pack_valid(struct packed_git *);
1230extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
1231extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
1232extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
1233extern int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
1234
1235struct object_info {
1236        /* Request */
1237        enum object_type *typep;
1238        unsigned long *sizep;
1239        unsigned long *disk_sizep;
1240        unsigned char *delta_base_sha1;
1241
1242        /* Response */
1243        enum {
1244                OI_CACHED,
1245                OI_LOOSE,
1246                OI_PACKED,
1247                OI_DBCACHED
1248        } whence;
1249        union {
1250                /*
1251                 * struct {
1252                 *      ... Nothing to expose in this case
1253                 * } cached;
1254                 * struct {
1255                 *      ... Nothing to expose in this case
1256                 * } loose;
1257                 */
1258                struct {
1259                        struct packed_git *pack;
1260                        off_t offset;
1261                        unsigned int is_delta;
1262                } packed;
1263        } u;
1264};
1265extern int sha1_object_info_extended(const unsigned char *, struct object_info *, unsigned flags);
1266
1267/* Dumb servers support */
1268extern int update_server_info(int);
1269
1270/* git_config_parse_key() returns these negated: */
1271#define CONFIG_INVALID_KEY 1
1272#define CONFIG_NO_SECTION_OR_NAME 2
1273/* git_config_set(), git_config_set_multivar() return the above or these: */
1274#define CONFIG_NO_LOCK -1
1275#define CONFIG_INVALID_FILE 3
1276#define CONFIG_NO_WRITE 4
1277#define CONFIG_NOTHING_SET 5
1278#define CONFIG_INVALID_PATTERN 6
1279#define CONFIG_GENERIC_ERROR 7
1280
1281struct git_config_source {
1282        unsigned int use_stdin:1;
1283        const char *file;
1284        const char *blob;
1285};
1286
1287typedef int (*config_fn_t)(const char *, const char *, void *);
1288extern int git_default_config(const char *, const char *, void *);
1289extern int git_config_from_file(config_fn_t fn, const char *, void *);
1290extern int git_config_from_buf(config_fn_t fn, const char *name,
1291                               const char *buf, size_t len, void *data);
1292extern void git_config_push_parameter(const char *text);
1293extern int git_config_from_parameters(config_fn_t fn, void *data);
1294extern int git_config(config_fn_t fn, void *);
1295extern int git_config_with_options(config_fn_t fn, void *,
1296                                   struct git_config_source *config_source,
1297                                   int respect_includes);
1298extern int git_config_early(config_fn_t fn, void *, const char *repo_config);
1299extern int git_parse_ulong(const char *, unsigned long *);
1300extern int git_config_int(const char *, const char *);
1301extern int64_t git_config_int64(const char *, const char *);
1302extern unsigned long git_config_ulong(const char *, const char *);
1303extern int git_config_bool_or_int(const char *, const char *, int *);
1304extern int git_config_bool(const char *, const char *);
1305extern int git_config_maybe_bool(const char *, const char *);
1306extern int git_config_string(const char **, const char *, const char *);
1307extern int git_config_pathname(const char **, const char *, const char *);
1308extern int git_config_set_in_file(const char *, const char *, const char *);
1309extern int git_config_set(const char *, const char *);
1310extern int git_config_parse_key(const char *, char **, int *);
1311extern int git_config_set_multivar(const char *, const char *, const char *, int);
1312extern int git_config_set_multivar_in_file(const char *, const char *, const char *, const char *, int);
1313extern int git_config_rename_section(const char *, const char *);
1314extern int git_config_rename_section_in_file(const char *, const char *, const char *);
1315extern const char *git_etc_gitconfig(void);
1316extern int check_repository_format_version(const char *var, const char *value, void *cb);
1317extern int git_env_bool(const char *, int);
1318extern int git_config_system(void);
1319extern int config_error_nonbool(const char *);
1320#if defined(__GNUC__)
1321#define config_error_nonbool(s) (config_error_nonbool(s), const_error())
1322#endif
1323extern const char *get_log_output_encoding(void);
1324extern const char *get_commit_output_encoding(void);
1325
1326extern int git_config_parse_parameter(const char *, config_fn_t fn, void *data);
1327
1328struct config_include_data {
1329        int depth;
1330        config_fn_t fn;
1331        void *data;
1332};
1333#define CONFIG_INCLUDE_INIT { 0 }
1334extern int git_config_include(const char *name, const char *value, void *data);
1335
1336/*
1337 * Match and parse a config key of the form:
1338 *
1339 *   section.(subsection.)?key
1340 *
1341 * (i.e., what gets handed to a config_fn_t). The caller provides the section;
1342 * we return -1 if it does not match, 0 otherwise. The subsection and key
1343 * out-parameters are filled by the function (and subsection is NULL if it is
1344 * missing).
1345 */
1346extern int parse_config_key(const char *var,
1347                            const char *section,
1348                            const char **subsection, int *subsection_len,
1349                            const char **key);
1350
1351extern int committer_ident_sufficiently_given(void);
1352extern int author_ident_sufficiently_given(void);
1353
1354extern const char *git_commit_encoding;
1355extern const char *git_log_output_encoding;
1356extern const char *git_mailmap_file;
1357extern const char *git_mailmap_blob;
1358
1359/* IO helper functions */
1360extern void maybe_flush_or_die(FILE *, const char *);
1361extern int copy_fd(int ifd, int ofd);
1362extern int copy_file(const char *dst, const char *src, int mode);
1363extern int copy_file_with_time(const char *dst, const char *src, int mode);
1364extern void write_or_die(int fd, const void *buf, size_t count);
1365extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
1366extern int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg);
1367extern void fsync_or_die(int fd, const char *);
1368
1369extern ssize_t read_in_full(int fd, void *buf, size_t count);
1370extern ssize_t write_in_full(int fd, const void *buf, size_t count);
1371extern ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset);
1372
1373static inline ssize_t write_str_in_full(int fd, const char *str)
1374{
1375        return write_in_full(fd, str, strlen(str));
1376}
1377
1378/* pager.c */
1379extern void setup_pager(void);
1380extern const char *pager_program;
1381extern int pager_in_use(void);
1382extern int pager_use_color;
1383extern int term_columns(void);
1384extern int decimal_width(int);
1385extern int check_pager_config(const char *cmd);
1386
1387extern const char *editor_program;
1388extern const char *askpass_program;
1389extern const char *excludes_file;
1390
1391/* base85 */
1392int decode_85(char *dst, const char *line, int linelen);
1393void encode_85(char *buf, const unsigned char *data, int bytes);
1394
1395/* alloc.c */
1396extern void *alloc_blob_node(void);
1397extern void *alloc_tree_node(void);
1398extern void *alloc_commit_node(void);
1399extern void *alloc_tag_node(void);
1400extern void *alloc_object_node(void);
1401extern void alloc_report(void);
1402
1403/* trace.c */
1404__attribute__((format (printf, 1, 2)))
1405extern void trace_printf(const char *format, ...);
1406__attribute__((format (printf, 2, 3)))
1407extern void trace_argv_printf(const char **argv, const char *format, ...);
1408extern void trace_repo_setup(const char *prefix);
1409extern int trace_want(const char *key);
1410__attribute__((format (printf, 2, 3)))
1411extern void trace_printf_key(const char *key, const char *fmt, ...);
1412extern void trace_strbuf(const char *key, const struct strbuf *buf);
1413
1414void packet_trace_identity(const char *prog);
1415
1416/* add */
1417/*
1418 * return 0 if success, 1 - if addition of a file failed and
1419 * ADD_FILES_IGNORE_ERRORS was specified in flags
1420 */
1421int add_files_to_cache(const char *prefix, const struct pathspec *pathspec, int flags);
1422
1423/* diff.c */
1424extern int diff_auto_refresh_index;
1425
1426/* match-trees.c */
1427void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
1428void shift_tree_by(const unsigned char *, const unsigned char *, unsigned char *, const char *);
1429
1430/*
1431 * whitespace rules.
1432 * used by both diff and apply
1433 * last two digits are tab width
1434 */
1435#define WS_BLANK_AT_EOL         0100
1436#define WS_SPACE_BEFORE_TAB     0200
1437#define WS_INDENT_WITH_NON_TAB  0400
1438#define WS_CR_AT_EOL           01000
1439#define WS_BLANK_AT_EOF        02000
1440#define WS_TAB_IN_INDENT       04000
1441#define WS_TRAILING_SPACE      (WS_BLANK_AT_EOL|WS_BLANK_AT_EOF)
1442#define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB|8)
1443#define WS_TAB_WIDTH_MASK        077
1444extern unsigned whitespace_rule_cfg;
1445extern unsigned whitespace_rule(const char *);
1446extern unsigned parse_whitespace_rule(const char *);
1447extern unsigned ws_check(const char *line, int len, unsigned ws_rule);
1448extern void ws_check_emit(const char *line, int len, unsigned ws_rule, FILE *stream, const char *set, const char *reset, const char *ws);
1449extern char *whitespace_error_string(unsigned ws);
1450extern void ws_fix_copy(struct strbuf *, const char *, int, unsigned, int *);
1451extern int ws_blank_line(const char *line, int len, unsigned ws_rule);
1452#define ws_tab_width(rule)     ((rule) & WS_TAB_WIDTH_MASK)
1453
1454/* ls-files */
1455int report_path_error(const char *ps_matched, const struct pathspec *pathspec, const char *prefix);
1456void overlay_tree_on_cache(const char *tree_name, const char *prefix);
1457
1458char *alias_lookup(const char *alias);
1459int split_cmdline(char *cmdline, const char ***argv);
1460/* Takes a negative value returned by split_cmdline */
1461const char *split_cmdline_strerror(int cmdline_errno);
1462
1463/* git.c */
1464struct startup_info {
1465        int have_repository;
1466        const char *prefix;
1467};
1468extern struct startup_info *startup_info;
1469
1470/* merge.c */
1471struct commit_list;
1472int try_merge_command(const char *strategy, size_t xopts_nr,
1473                const char **xopts, struct commit_list *common,
1474                const char *head_arg, struct commit_list *remotes);
1475int checkout_fast_forward(const unsigned char *from,
1476                          const unsigned char *to,
1477                          int overwrite_ignore);
1478
1479
1480int sane_execvp(const char *file, char *const argv[]);
1481
1482/*
1483 * A struct to encapsulate the concept of whether a file has changed
1484 * since we last checked it. This uses criteria similar to those used
1485 * for the index.
1486 */
1487struct stat_validity {
1488        struct stat_data *sd;
1489};
1490
1491void stat_validity_clear(struct stat_validity *sv);
1492
1493/*
1494 * Returns 1 if the path is a regular file (or a symlink to a regular
1495 * file) and matches the saved stat_validity, 0 otherwise.  A missing
1496 * or inaccessible file is considered a match if the struct was just
1497 * initialized, or if the previous update found an inaccessible file.
1498 */
1499int stat_validity_check(struct stat_validity *sv, const char *path);
1500
1501/*
1502 * Update the stat_validity from a file opened at descriptor fd. If
1503 * the file is missing, inaccessible, or not a regular file, then
1504 * future calls to stat_validity_check will match iff one of those
1505 * conditions continues to be true.
1506 */
1507void stat_validity_update(struct stat_validity *sv, int fd);
1508
1509int versioncmp(const char *s1, const char *s2);
1510
1511#endif /* CACHE_H */