cache.hon commit Documentation/git-svn: clarify dcommit, rebase vs pull/merge (2eff142)
   1#ifndef CACHE_H
   2#define CACHE_H
   3
   4#include "git-compat-util.h"
   5
   6#include SHA1_HEADER
   7#include <zlib.h>
   8
   9#if ZLIB_VERNUM < 0x1200
  10#define deflateBound(c,s)  ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
  11#endif
  12
  13#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT)
  14#define DTYPE(de)       ((de)->d_type)
  15#else
  16#undef DT_UNKNOWN
  17#undef DT_DIR
  18#undef DT_REG
  19#undef DT_LNK
  20#define DT_UNKNOWN      0
  21#define DT_DIR          1
  22#define DT_REG          2
  23#define DT_LNK          3
  24#define DTYPE(de)       DT_UNKNOWN
  25#endif
  26
  27/*
  28 * Intensive research over the course of many years has shown that
  29 * port 9418 is totally unused by anything else. Or
  30 *
  31 *      Your search - "port 9418" - did not match any documents.
  32 *
  33 * as www.google.com puts it.
  34 *
  35 * This port has been properly assigned for git use by IANA:
  36 * git (Assigned-9418) [I06-050728-0001].
  37 *
  38 *      git  9418/tcp   git pack transfer service
  39 *      git  9418/udp   git pack transfer service
  40 *
  41 * with Linus Torvalds <torvalds@osdl.org> as the point of
  42 * contact. September 2005.
  43 *
  44 * See http://www.iana.org/assignments/port-numbers
  45 */
  46#define DEFAULT_GIT_PORT 9418
  47
  48/*
  49 * Basic data structures for the directory cache
  50 */
  51
  52#define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
  53struct cache_header {
  54        unsigned int hdr_signature;
  55        unsigned int hdr_version;
  56        unsigned int hdr_entries;
  57};
  58
  59/*
  60 * The "cache_time" is just the low 32 bits of the
  61 * time. It doesn't matter if it overflows - we only
  62 * check it for equality in the 32 bits we save.
  63 */
  64struct cache_time {
  65        unsigned int sec;
  66        unsigned int nsec;
  67};
  68
  69/*
  70 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
  71 * Again - this is just a (very strong in practice) heuristic that
  72 * the inode hasn't changed.
  73 *
  74 * We save the fields in big-endian order to allow using the
  75 * index file over NFS transparently.
  76 */
  77struct cache_entry {
  78        struct cache_time ce_ctime;
  79        struct cache_time ce_mtime;
  80        unsigned int ce_dev;
  81        unsigned int ce_ino;
  82        unsigned int ce_mode;
  83        unsigned int ce_uid;
  84        unsigned int ce_gid;
  85        unsigned int ce_size;
  86        unsigned char sha1[20];
  87        unsigned short ce_flags;
  88        char name[FLEX_ARRAY]; /* more */
  89};
  90
  91#define CE_NAMEMASK  (0x0fff)
  92#define CE_STAGEMASK (0x3000)
  93#define CE_UPDATE    (0x4000)
  94#define CE_VALID     (0x8000)
  95#define CE_STAGESHIFT 12
  96
  97#define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
  98#define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
  99#define ce_size(ce) cache_entry_size(ce_namelen(ce))
 100#define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
 101
 102#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 103static inline unsigned int create_ce_mode(unsigned int mode)
 104{
 105        if (S_ISLNK(mode))
 106                return htonl(S_IFLNK);
 107        return htonl(S_IFREG | ce_permissions(mode));
 108}
 109#define canon_mode(mode) \
 110        (S_ISREG(mode) ? (S_IFREG | ce_permissions(mode)) : \
 111        S_ISLNK(mode) ? S_IFLNK : S_IFDIR)
 112
 113#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
 114
 115extern struct cache_entry **active_cache;
 116extern unsigned int active_nr, active_alloc, active_cache_changed;
 117extern struct cache_tree *active_cache_tree;
 118extern int cache_errno;
 119
 120#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 121#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 122#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 123#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 124#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 125#define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
 126#define CONFIG_ENVIRONMENT "GIT_CONFIG"
 127#define CONFIG_LOCAL_ENVIRONMENT "GIT_CONFIG_LOCAL"
 128#define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 129
 130extern int is_bare_git_dir(const char *dir);
 131extern const char *get_git_dir(void);
 132extern char *get_object_directory(void);
 133extern char *get_refs_directory(void);
 134extern char *get_index_file(void);
 135extern char *get_graft_file(void);
 136
 137#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 138
 139extern const char **get_pathspec(const char *prefix, const char **pathspec);
 140extern const char *setup_git_directory_gently(int *);
 141extern const char *setup_git_directory(void);
 142extern const char *prefix_path(const char *prefix, int len, const char *path);
 143extern const char *prefix_filename(const char *prefix, int len, const char *path);
 144extern void verify_filename(const char *prefix, const char *name);
 145extern void verify_non_filename(const char *prefix, const char *name);
 146
 147#define alloc_nr(x) (((x)+16)*3/2)
 148
 149/* Initialize and use the cache information */
 150extern int read_cache(void);
 151extern int read_cache_from(const char *path);
 152extern int write_cache(int newfd, struct cache_entry **cache, int entries);
 153extern int discard_cache(void);
 154extern int verify_path(const char *path);
 155extern int cache_name_pos(const char *name, int namelen);
 156#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 157#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 158#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 159extern int add_cache_entry(struct cache_entry *ce, int option);
 160extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
 161extern int remove_cache_entry_at(int pos);
 162extern int remove_file_from_cache(const char *path);
 163extern int add_file_to_index(const char *path, int verbose);
 164extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 165extern int ce_match_stat(struct cache_entry *ce, struct stat *st, int);
 166extern int ce_modified(struct cache_entry *ce, struct stat *st, int);
 167extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 168extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type);
 169extern int read_pipe(int fd, char** return_buf, unsigned long* return_size);
 170extern int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object);
 171extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
 172extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 173
 174#define REFRESH_REALLY          0x0001  /* ignore_valid */
 175#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 176#define REFRESH_QUIET           0x0004  /* be quiet about it */
 177#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 178extern int refresh_cache(unsigned int flags);
 179
 180struct lock_file {
 181        struct lock_file *next;
 182        char on_list;
 183        char filename[PATH_MAX];
 184};
 185extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 186extern int commit_lock_file(struct lock_file *);
 187extern void rollback_lock_file(struct lock_file *);
 188extern int delete_ref(const char *, unsigned char *sha1);
 189
 190/* Environment bits from configuration mechanism */
 191extern int use_legacy_headers;
 192extern int trust_executable_bit;
 193extern int assume_unchanged;
 194extern int prefer_symlink_refs;
 195extern int log_all_ref_updates;
 196extern int warn_ambiguous_refs;
 197extern int shared_repository;
 198extern const char *apply_default_whitespace;
 199extern int zlib_compression_level;
 200
 201#define GIT_REPO_VERSION 0
 202extern int repository_format_version;
 203extern int check_repository_format(void);
 204
 205#define MTIME_CHANGED   0x0001
 206#define CTIME_CHANGED   0x0002
 207#define OWNER_CHANGED   0x0004
 208#define MODE_CHANGED    0x0008
 209#define INODE_CHANGED   0x0010
 210#define DATA_CHANGED    0x0020
 211#define TYPE_CHANGED    0x0040
 212
 213/* Return a statically allocated filename matching the sha1 signature */
 214extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 215extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 216extern char *sha1_file_name(const unsigned char *sha1);
 217extern char *sha1_pack_name(const unsigned char *sha1);
 218extern char *sha1_pack_index_name(const unsigned char *sha1);
 219extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 220extern const unsigned char null_sha1[20];
 221static inline int is_null_sha1(const unsigned char *sha1)
 222{
 223        return !memcmp(sha1, null_sha1, 20);
 224}
 225static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 226{
 227        return memcmp(sha1, sha2, 20);
 228}
 229static inline void hashcpy(unsigned char *sha_dst, const unsigned char *sha_src)
 230{
 231        memcpy(sha_dst, sha_src, 20);
 232}
 233static inline void hashclr(unsigned char *hash)
 234{
 235        memset(hash, 0, 20);
 236}
 237
 238int git_mkstemp(char *path, size_t n, const char *template);
 239
 240enum sharedrepo {
 241        PERM_UMASK = 0,
 242        PERM_GROUP,
 243        PERM_EVERYBODY
 244};
 245int git_config_perm(const char *var, const char *value);
 246int adjust_shared_perm(const char *path);
 247int safe_create_leading_directories(char *path);
 248char *enter_repo(char *path, int strict);
 249
 250/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 251extern int sha1_object_info(const unsigned char *, char *, unsigned long *);
 252extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
 253extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
 254extern int hash_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *sha1);
 255extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 256
 257extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 258
 259extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
 260                              size_t bufsize, size_t *bufposn);
 261extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
 262extern int move_temp_to_file(const char *tmpfile, const char *filename);
 263
 264extern int has_sha1_pack(const unsigned char *sha1, const char **ignore);
 265extern int has_sha1_file(const unsigned char *sha1);
 266extern void *map_sha1_file(const unsigned char *sha1, unsigned long *);
 267extern int legacy_loose_object(unsigned char *);
 268
 269extern int has_pack_file(const unsigned char *sha1);
 270extern int has_pack_index(const unsigned char *sha1);
 271
 272enum object_type {
 273        OBJ_NONE = 0,
 274        OBJ_COMMIT = 1,
 275        OBJ_TREE = 2,
 276        OBJ_BLOB = 3,
 277        OBJ_TAG = 4,
 278        /* 5 for future expansion */
 279        OBJ_OFS_DELTA = 6,
 280        OBJ_REF_DELTA = 7,
 281        OBJ_BAD,
 282};
 283
 284extern signed char hexval_table[256];
 285static inline unsigned int hexval(unsigned int c)
 286{
 287        return hexval_table[c];
 288}
 289
 290/* Convert to/from hex/sha1 representation */
 291#define MINIMUM_ABBREV 4
 292#define DEFAULT_ABBREV 7
 293
 294extern int get_sha1(const char *str, unsigned char *sha1);
 295extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 296extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 297extern int read_ref(const char *filename, unsigned char *sha1);
 298extern const char *resolve_ref(const char *path, unsigned char *sha1, int, int *);
 299extern int create_symref(const char *ref, const char *refs_heads_master);
 300extern int validate_symref(const char *ref);
 301
 302extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 303extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 304
 305extern void *read_object_with_reference(const unsigned char *sha1,
 306                                        const char *required_type,
 307                                        unsigned long *size,
 308                                        unsigned char *sha1_ret);
 309
 310const char *show_date(unsigned long time, int timezone, int relative);
 311const char *show_rfc2822_date(unsigned long time, int timezone);
 312int parse_date(const char *date, char *buf, int bufsize);
 313void datestamp(char *buf, int bufsize);
 314unsigned long approxidate(const char *);
 315
 316extern int setup_ident(void);
 317extern void ignore_missing_committer_name();
 318extern const char *git_author_info(int);
 319extern const char *git_committer_info(int);
 320
 321struct checkout {
 322        const char *base_dir;
 323        int base_dir_len;
 324        unsigned force:1,
 325                 quiet:1,
 326                 not_new:1,
 327                 refresh_cache:1;
 328};
 329
 330extern int checkout_entry(struct cache_entry *ce, struct checkout *state, char *topath);
 331
 332extern struct alternate_object_database {
 333        struct alternate_object_database *next;
 334        char *name;
 335        char base[FLEX_ARRAY]; /* more */
 336} *alt_odb_list;
 337extern void prepare_alt_odb(void);
 338
 339extern struct packed_git {
 340        struct packed_git *next;
 341        unsigned long index_size;
 342        unsigned long pack_size;
 343        unsigned int *index_base;
 344        void *pack_base;
 345        unsigned int pack_last_used;
 346        unsigned int pack_use_cnt;
 347        int pack_local;
 348        unsigned char sha1[20];
 349        /* something like ".git/objects/pack/xxxxx.pack" */
 350        char pack_name[FLEX_ARRAY]; /* more */
 351} *packed_git;
 352
 353struct pack_entry {
 354        unsigned int offset;
 355        unsigned char sha1[20];
 356        struct packed_git *p;
 357};
 358
 359struct ref {
 360        struct ref *next;
 361        unsigned char old_sha1[20];
 362        unsigned char new_sha1[20];
 363        unsigned char force;
 364        struct ref *peer_ref; /* when renaming */
 365        char name[FLEX_ARRAY]; /* more */
 366};
 367
 368#define REF_NORMAL      (1u << 0)
 369#define REF_HEADS       (1u << 1)
 370#define REF_TAGS        (1u << 2)
 371
 372extern pid_t git_connect(int fd[2], char *url, const char *prog);
 373extern int finish_connect(pid_t pid);
 374extern int path_match(const char *path, int nr, char **match);
 375extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 376                      int nr_refspec, char **refspec, int all);
 377extern int get_ack(int fd, unsigned char *result_sha1);
 378extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match, unsigned int flags);
 379extern int server_supports(const char *feature);
 380
 381extern struct packed_git *parse_pack_index(unsigned char *sha1);
 382extern struct packed_git *parse_pack_index_file(const unsigned char *sha1,
 383                                                char *idx_path);
 384
 385extern void prepare_packed_git(void);
 386extern void reprepare_packed_git(void);
 387extern void install_packed_git(struct packed_git *pack);
 388
 389extern struct packed_git *find_sha1_pack(const unsigned char *sha1, 
 390                                         struct packed_git *packs);
 391
 392extern int use_packed_git(struct packed_git *);
 393extern void unuse_packed_git(struct packed_git *);
 394extern struct packed_git *add_packed_git(char *, int, int);
 395extern int num_packed_objects(const struct packed_git *p);
 396extern int nth_packed_object_sha1(const struct packed_git *, int, unsigned char*);
 397extern unsigned long find_pack_entry_one(const unsigned char *, struct packed_git *);
 398extern void *unpack_entry_gently(struct packed_git *, unsigned long, char *, unsigned long *);
 399extern unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 400extern void packed_object_info_detail(struct packed_git *, unsigned long, char *, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
 401
 402/* Dumb servers support */
 403extern int update_server_info(int);
 404
 405typedef int (*config_fn_t)(const char *, const char *);
 406extern int git_default_config(const char *, const char *);
 407extern int git_config_from_file(config_fn_t fn, const char *);
 408extern int git_config(config_fn_t fn);
 409extern int git_config_int(const char *, const char *);
 410extern int git_config_bool(const char *, const char *);
 411extern int git_config_set(const char *, const char *);
 412extern int git_config_set_multivar(const char *, const char *, const char *, int);
 413extern int git_config_rename_section(const char *, const char *);
 414extern int check_repository_format_version(const char *var, const char *value);
 415
 416#define MAX_GITNAME (1000)
 417extern char git_default_email[MAX_GITNAME];
 418extern char git_default_name[MAX_GITNAME];
 419
 420extern char *git_commit_encoding;
 421extern char *git_log_output_encoding;
 422
 423extern int copy_fd(int ifd, int ofd);
 424extern int write_in_full(int fd, const void *buf, size_t count, const char *);
 425extern void write_or_die(int fd, const void *buf, size_t count);
 426extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg);
 427
 428/* pager.c */
 429extern void setup_pager(void);
 430extern int pager_in_use;
 431extern int pager_use_color;
 432
 433/* base85 */
 434int decode_85(char *dst, char *line, int linelen);
 435void encode_85(char *buf, unsigned char *data, int bytes);
 436
 437/* alloc.c */
 438struct blob;
 439struct tree;
 440struct commit;
 441struct tag;
 442extern struct blob *alloc_blob_node(void);
 443extern struct tree *alloc_tree_node(void);
 444extern struct commit *alloc_commit_node(void);
 445extern struct tag *alloc_tag_node(void);
 446extern void alloc_report(void);
 447
 448/* trace.c */
 449extern int nfvasprintf(char **str, const char *fmt, va_list va);
 450extern void trace_printf(const char *format, ...);
 451extern void trace_argv_printf(const char **argv, int count, const char *format, ...);
 452
 453#endif /* CACHE_H */