cache.hon commit gitweb: Support for snapshot (cb9c6e5)
   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
 126extern char *get_git_dir(void);
 127extern char *get_object_directory(void);
 128extern char *get_refs_directory(void);
 129extern char *get_index_file(void);
 130extern char *get_graft_file(void);
 131
 132#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 133
 134extern const char **get_pathspec(const char *prefix, const char **pathspec);
 135extern const char *setup_git_directory_gently(int *);
 136extern const char *setup_git_directory(void);
 137extern const char *prefix_path(const char *prefix, int len, const char *path);
 138extern const char *prefix_filename(const char *prefix, int len, const char *path);
 139extern void verify_filename(const char *prefix, const char *name);
 140extern void verify_non_filename(const char *prefix, const char *name);
 141
 142#define alloc_nr(x) (((x)+16)*3/2)
 143
 144/* Initialize and use the cache information */
 145extern int read_cache(void);
 146extern int read_cache_from(const char *path);
 147extern int write_cache(int newfd, struct cache_entry **cache, int entries);
 148extern int verify_path(const char *path);
 149extern int cache_name_pos(const char *name, int namelen);
 150#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 151#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 152#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 153extern int add_cache_entry(struct cache_entry *ce, int option);
 154extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
 155extern int remove_cache_entry_at(int pos);
 156extern int remove_file_from_cache(const char *path);
 157extern int add_file_to_index(const char *path, int verbose);
 158extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 159extern int ce_match_stat(struct cache_entry *ce, struct stat *st, int);
 160extern int ce_modified(struct cache_entry *ce, struct stat *st, int);
 161extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 162extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type);
 163extern int read_pipe(int fd, char** return_buf, unsigned long* return_size);
 164extern int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object);
 165extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
 166extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 167
 168#define REFRESH_REALLY          0x0001  /* ignore_valid */
 169#define REFRESH_UNMERGED        0x0002  /* allow unmerged */
 170#define REFRESH_QUIET           0x0004  /* be quiet about it */
 171#define REFRESH_IGNORE_MISSING  0x0008  /* ignore non-existent */
 172extern int refresh_cache(unsigned int flags);
 173
 174struct lock_file {
 175        struct lock_file *next;
 176        char filename[PATH_MAX];
 177};
 178extern int hold_lock_file_for_update(struct lock_file *, const char *path, int);
 179extern int commit_lock_file(struct lock_file *);
 180extern void rollback_lock_file(struct lock_file *);
 181
 182/* Environment bits from configuration mechanism */
 183extern int use_legacy_headers;
 184extern int trust_executable_bit;
 185extern int assume_unchanged;
 186extern int prefer_symlink_refs;
 187extern int log_all_ref_updates;
 188extern int warn_ambiguous_refs;
 189extern int shared_repository;
 190extern const char *apply_default_whitespace;
 191extern int zlib_compression_level;
 192
 193#define GIT_REPO_VERSION 0
 194extern int repository_format_version;
 195extern int check_repository_format(void);
 196
 197#define MTIME_CHANGED   0x0001
 198#define CTIME_CHANGED   0x0002
 199#define OWNER_CHANGED   0x0004
 200#define MODE_CHANGED    0x0008
 201#define INODE_CHANGED   0x0010
 202#define DATA_CHANGED    0x0020
 203#define TYPE_CHANGED    0x0040
 204
 205/* Return a statically allocated filename matching the sha1 signature */
 206extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 207extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 208extern char *sha1_file_name(const unsigned char *sha1);
 209extern char *sha1_pack_name(const unsigned char *sha1);
 210extern char *sha1_pack_index_name(const unsigned char *sha1);
 211extern const char *find_unique_abbrev(const unsigned char *sha1, int);
 212extern const unsigned char null_sha1[20];
 213static inline int is_null_sha1(const unsigned char *sha1)
 214{
 215        return !memcmp(sha1, null_sha1, 20);
 216}
 217
 218int git_mkstemp(char *path, size_t n, const char *template);
 219
 220enum sharedrepo {
 221        PERM_UMASK = 0,
 222        PERM_GROUP,
 223        PERM_EVERYBODY
 224};
 225int git_config_perm(const char *var, const char *value);
 226int adjust_shared_perm(const char *path);
 227int safe_create_leading_directories(char *path);
 228char *enter_repo(char *path, int strict);
 229
 230/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 231extern int sha1_object_info(const unsigned char *, char *, unsigned long *);
 232extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
 233extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
 234extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 235extern char *write_sha1_file_prepare(void *buf,
 236                                     unsigned long len,
 237                                     const char *type,
 238                                     unsigned char *sha1,
 239                                     unsigned char *hdr,
 240                                     int *hdrlen);
 241
 242extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 243
 244extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
 245                              size_t bufsize, size_t *bufposn);
 246extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
 247extern int move_temp_to_file(const char *tmpfile, char *filename);
 248
 249extern int has_sha1_pack(const unsigned char *sha1);
 250extern int has_sha1_file(const unsigned char *sha1);
 251extern void *map_sha1_file(const unsigned char *sha1, unsigned long *);
 252extern int legacy_loose_object(unsigned char *);
 253
 254extern int has_pack_file(const unsigned char *sha1);
 255extern int has_pack_index(const unsigned char *sha1);
 256
 257/* Convert to/from hex/sha1 representation */
 258#define MINIMUM_ABBREV 4
 259#define DEFAULT_ABBREV 7
 260
 261extern int get_sha1(const char *str, unsigned char *sha1);
 262extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 263extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 264extern int read_ref(const char *filename, unsigned char *sha1);
 265extern const char *resolve_ref(const char *path, unsigned char *sha1, int);
 266extern int create_symref(const char *git_HEAD, const char *refs_heads_master);
 267extern int validate_symref(const char *git_HEAD);
 268
 269extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 270extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 271
 272extern void *read_object_with_reference(const unsigned char *sha1,
 273                                        const char *required_type,
 274                                        unsigned long *size,
 275                                        unsigned char *sha1_ret);
 276
 277const char *show_date(unsigned long time, int timezone);
 278const char *show_rfc2822_date(unsigned long time, int timezone);
 279int parse_date(const char *date, char *buf, int bufsize);
 280void datestamp(char *buf, int bufsize);
 281unsigned long approxidate(const char *);
 282
 283extern int setup_ident(void);
 284extern const char *git_author_info(int);
 285extern const char *git_committer_info(int);
 286
 287struct checkout {
 288        const char *base_dir;
 289        int base_dir_len;
 290        unsigned force:1,
 291                 quiet:1,
 292                 not_new:1,
 293                 refresh_cache:1;
 294};
 295
 296extern int checkout_entry(struct cache_entry *ce, struct checkout *state, char *topath);
 297
 298extern struct alternate_object_database {
 299        struct alternate_object_database *next;
 300        char *name;
 301        char base[FLEX_ARRAY]; /* more */
 302} *alt_odb_list;
 303extern void prepare_alt_odb(void);
 304
 305extern struct packed_git {
 306        struct packed_git *next;
 307        unsigned long index_size;
 308        unsigned long pack_size;
 309        unsigned int *index_base;
 310        void *pack_base;
 311        unsigned int pack_last_used;
 312        unsigned int pack_use_cnt;
 313        int pack_local;
 314        unsigned char sha1[20];
 315        /* something like ".git/objects/pack/xxxxx.pack" */
 316        char pack_name[FLEX_ARRAY]; /* more */
 317} *packed_git;
 318
 319struct pack_entry {
 320        unsigned int offset;
 321        unsigned char sha1[20];
 322        struct packed_git *p;
 323};
 324
 325struct ref {
 326        struct ref *next;
 327        unsigned char old_sha1[20];
 328        unsigned char new_sha1[20];
 329        unsigned char force;
 330        struct ref *peer_ref; /* when renaming */
 331        char name[FLEX_ARRAY]; /* more */
 332};
 333
 334#define REF_NORMAL      (1u << 0)
 335#define REF_HEADS       (1u << 1)
 336#define REF_TAGS        (1u << 2)
 337
 338extern int git_connect(int fd[2], char *url, const char *prog);
 339extern int finish_connect(pid_t pid);
 340extern int path_match(const char *path, int nr, char **match);
 341extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 342                      int nr_refspec, char **refspec, int all);
 343extern int get_ack(int fd, unsigned char *result_sha1);
 344extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match, unsigned int flags);
 345extern int server_supports(const char *feature);
 346
 347extern struct packed_git *parse_pack_index(unsigned char *sha1);
 348extern struct packed_git *parse_pack_index_file(const unsigned char *sha1,
 349                                                char *idx_path);
 350
 351extern void prepare_packed_git(void);
 352extern void install_packed_git(struct packed_git *pack);
 353
 354extern struct packed_git *find_sha1_pack(const unsigned char *sha1, 
 355                                         struct packed_git *packs);
 356
 357extern int use_packed_git(struct packed_git *);
 358extern void unuse_packed_git(struct packed_git *);
 359extern struct packed_git *add_packed_git(char *, int, int);
 360extern int num_packed_objects(const struct packed_git *p);
 361extern int nth_packed_object_sha1(const struct packed_git *, int, unsigned char*);
 362extern int find_pack_entry_one(const unsigned char *, struct pack_entry *, struct packed_git *);
 363extern void *unpack_entry_gently(struct pack_entry *, char *, unsigned long *);
 364extern void packed_object_info_detail(struct pack_entry *, char *, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
 365
 366/* Dumb servers support */
 367extern int update_server_info(int);
 368
 369typedef int (*config_fn_t)(const char *, const char *);
 370extern int git_default_config(const char *, const char *);
 371extern int git_config_from_file(config_fn_t fn, const char *);
 372extern int git_config(config_fn_t fn);
 373extern int git_config_int(const char *, const char *);
 374extern int git_config_bool(const char *, const char *);
 375extern int git_config_set(const char *, const char *);
 376extern int git_config_set_multivar(const char *, const char *, const char *, int);
 377extern int check_repository_format_version(const char *var, const char *value);
 378
 379#define MAX_GITNAME (1000)
 380extern char git_default_email[MAX_GITNAME];
 381extern char git_default_name[MAX_GITNAME];
 382
 383#define MAX_ENCODING_LENGTH 64
 384extern char git_commit_encoding[MAX_ENCODING_LENGTH];
 385
 386extern int copy_fd(int ifd, int ofd);
 387
 388/* Finish off pack transfer receiving end */
 389extern int receive_unpack_pack(int fd[2], const char *me, int quiet, int);
 390extern int receive_keep_pack(int fd[2], const char *me, int quiet, int);
 391
 392/* pager.c */
 393extern void setup_pager(void);
 394extern int pager_in_use;
 395extern int pager_use_color;
 396
 397/* base85 */
 398int decode_85(char *dst, char *line, int linelen);
 399void encode_85(char *buf, unsigned char *data, int bytes);
 400
 401/* alloc.c */
 402struct blob;
 403struct tree;
 404struct commit;
 405struct tag;
 406extern struct blob *alloc_blob_node(void);
 407extern struct tree *alloc_tree_node(void);
 408extern struct commit *alloc_commit_node(void);
 409extern struct tag *alloc_tag_node(void);
 410extern void alloc_report(void);
 411
 412#endif /* CACHE_H */