Andrew's git - gitweb.git/blob

   1#ifndef CACHE_H
   2#define CACHE_H
   3
   4#include <unistd.h>
   5#include <stdio.h>
   6#include <sys/stat.h>
   7#include <fcntl.h>
   8#include <stddef.h>
   9#include <stdlib.h>
  10#include <stdarg.h>
  11#include <string.h>
  12#include <errno.h>
  13#include <limits.h>
  14#include <sys/mman.h>
  15#include <sys/param.h>
  16#include <netinet/in.h>
  17#include <sys/types.h>
  18#include <dirent.h>
  19
  20#include SHA1_HEADER
  21#include <zlib.h>
  22
  23#if ZLIB_VERNUM < 0x1200
  24#define deflateBound(c,s)  ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
  25#endif
  26
  27#ifdef DT_UNKNOWN
  28#define DTYPE(de)       ((de)->d_type)
  29#else
  30#define DT_UNKNOWN      0
  31#define DT_DIR          1
  32#define DT_REG          2
  33#define DT_LNK          3
  34#define DTYPE(de)       DT_UNKNOWN
  35#endif
  36
  37#ifdef __GNUC__
  38#define NORETURN __attribute__((__noreturn__))
  39#else
  40#define NORETURN
  41#ifndef __attribute__
  42#define __attribute__(x)
  43#endif
  44#endif
  45
  46/*
  47 * Intensive research over the course of many years has shown that
  48 * port 9418 is totally unused by anything else. Or
  49 *
  50 *      Your search - "port 9418" - did not match any documents.
  51 *
  52 * as www.google.com puts it.
  53 */
  54#define DEFAULT_GIT_PORT 9418
  55
  56/*
  57 * Environment variables transition.
  58 * We accept older names for now but warn.
  59 */
  60extern char *gitenv_bc(const char *);
  61#define gitenv(e) (getenv(e) ? : gitenv_bc(e))
  62
  63/*
  64 * Basic data structures for the directory cache
  65 */
  66
  67#define CACHE_SIGNATURE 0x44495243      /* "DIRC" */
  68struct cache_header {
  69        unsigned int hdr_signature;
  70        unsigned int hdr_version;
  71        unsigned int hdr_entries;
  72};
  73
  74/*
  75 * The "cache_time" is just the low 32 bits of the
  76 * time. It doesn't matter if it overflows - we only
  77 * check it for equality in the 32 bits we save.
  78 */
  79struct cache_time {
  80        unsigned int sec;
  81        unsigned int nsec;
  82};
  83
  84/*
  85 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
  86 * Again - this is just a (very strong in practice) heuristic that
  87 * the inode hasn't changed.
  88 *
  89 * We save the fields in big-endian order to allow using the
  90 * index file over NFS transparently.
  91 */
  92struct cache_entry {
  93        struct cache_time ce_ctime;
  94        struct cache_time ce_mtime;
  95        unsigned int ce_dev;
  96        unsigned int ce_ino;
  97        unsigned int ce_mode;
  98        unsigned int ce_uid;
  99        unsigned int ce_gid;
 100        unsigned int ce_size;
 101        unsigned char sha1[20];
 102        unsigned short ce_flags;
 103        char name[0];
 104};
 105
 106#define CE_NAMEMASK  (0x0fff)
 107#define CE_STAGEMASK (0x3000)
 108#define CE_UPDATE    (0x4000)
 109#define CE_STAGESHIFT 12
 110
 111#define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
 112#define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
 113#define ce_size(ce) cache_entry_size(ce_namelen(ce))
 114#define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
 115
 116#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
 117static inline unsigned int create_ce_mode(unsigned int mode)
 118{
 119        if (S_ISLNK(mode))
 120                return htonl(S_IFLNK);
 121        return htonl(S_IFREG | ce_permissions(mode));
 122}
 123
 124#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
 125
 126extern struct cache_entry **active_cache;
 127extern unsigned int active_nr, active_alloc, active_cache_changed;
 128
 129#define GIT_DIR_ENVIRONMENT "GIT_DIR"
 130#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 131#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 132#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
 133#define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
 134
 135extern char *get_object_directory(void);
 136extern char *get_refs_directory(void);
 137extern char *get_index_file(void);
 138extern char *get_graft_file(void);
 139
 140#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 141
 142extern const char **get_pathspec(const char *prefix, char **pathspec);
 143extern const char *setup_git_directory(void);
 144extern char *prefix_path(const char *prefix, int len, char *path);
 145
 146#define alloc_nr(x) (((x)+16)*3/2)
 147
 148/* Initialize and use the cache information */
 149extern int read_cache(void);
 150extern int write_cache(int newfd, struct cache_entry **cache, int entries);
 151extern int cache_name_pos(const char *name, int namelen);
 152#define ADD_CACHE_OK_TO_ADD 1           /* Ok to add */
 153#define ADD_CACHE_OK_TO_REPLACE 2       /* Ok to replace file/directory */
 154#define ADD_CACHE_SKIP_DFCHECK 4        /* Ok to skip DF conflict checks */
 155extern int add_cache_entry(struct cache_entry *ce, int option);
 156extern int remove_cache_entry_at(int pos);
 157extern int remove_file_from_cache(char *path);
 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);
 160extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 161extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type);
 162extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
 163
 164struct cache_file {
 165        struct cache_file *next;
 166        char lockfile[PATH_MAX];
 167};
 168extern int hold_index_file_for_update(struct cache_file *, const char *path);
 169extern int commit_index_file(struct cache_file *);
 170extern void rollback_index_file(struct cache_file *);
 171
 172#define MTIME_CHANGED   0x0001
 173#define CTIME_CHANGED   0x0002
 174#define OWNER_CHANGED   0x0004
 175#define MODE_CHANGED    0x0008
 176#define INODE_CHANGED   0x0010
 177#define DATA_CHANGED    0x0020
 178#define TYPE_CHANGED    0x0040
 179
 180/* Return a statically allocated filename matching the sha1 signature */
 181extern char *mkpath(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 182extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)));
 183extern char *sha1_file_name(const unsigned char *sha1);
 184extern char *sha1_pack_name(const unsigned char *sha1);
 185extern char *sha1_pack_index_name(const unsigned char *sha1);
 186
 187int git_mkstemp(char *path, size_t n, const char *template);
 188
 189int safe_create_leading_directories(char *path);
 190char *safe_strncpy(char *, const char *, size_t);
 191
 192/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 193extern int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size);
 194extern int parse_sha1_header(char *hdr, char *type, unsigned long *sizep);
 195extern int sha1_object_info(const unsigned char *, char *, unsigned long *);
 196extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
 197extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
 198extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
 199extern char *write_sha1_file_prepare(void *buf,
 200                                     unsigned long len,
 201                                     const char *type,
 202                                     unsigned char *sha1,
 203                                     unsigned char *hdr,
 204                                     int *hdrlen);
 205
 206extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 207
 208/* Read a tree into the cache */
 209extern int read_tree(void *buffer, unsigned long size, int stage, const char **paths);
 210
 211extern int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
 212                              size_t bufsize, size_t *bufposn);
 213extern int write_sha1_to_fd(int fd, const unsigned char *sha1);
 214
 215extern int has_sha1_pack(const unsigned char *sha1);
 216extern int has_sha1_file(const unsigned char *sha1);
 217
 218extern int has_pack_file(const unsigned char *sha1);
 219extern int has_pack_index(const unsigned char *sha1);
 220
 221/* Convert to/from hex/sha1 representation */
 222extern int get_sha1(const char *str, unsigned char *sha1);
 223extern int get_sha1_hex(const char *hex, unsigned char *sha1);
 224extern char *sha1_to_hex(const unsigned char *sha1);    /* static buffer result! */
 225
 226/* General helper functions */
 227extern void usage(const char *err) NORETURN;
 228extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
 229extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 230
 231extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 232extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 233
 234extern void *read_object_with_reference(const unsigned char *sha1,
 235                                        const char *required_type,
 236                                        unsigned long *size,
 237                                        unsigned char *sha1_ret);
 238
 239const char *show_date(unsigned long time, int timezone);
 240void parse_date(const char *date, char *buf, int bufsize);
 241void datestamp(char *buf, int bufsize);
 242
 243extern int setup_ident(void);
 244extern char *get_ident(const char *name, const char *email, const char *date_str);
 245extern char *git_author_info(void);
 246extern char *git_committer_info(void);
 247
 248static inline void *xmalloc(size_t size)
 249{
 250        void *ret = malloc(size);
 251        if (!ret)
 252                die("Out of memory, malloc failed");
 253        return ret;
 254}
 255
 256static inline void *xrealloc(void *ptr, size_t size)
 257{
 258        void *ret = realloc(ptr, size);
 259        if (!ret)
 260                die("Out of memory, realloc failed");
 261        return ret;
 262}
 263
 264static inline void *xcalloc(size_t nmemb, size_t size)
 265{
 266        void *ret = calloc(nmemb, size);
 267        if (!ret)
 268                die("Out of memory, calloc failed");
 269        return ret;
 270}
 271
 272struct checkout {
 273        const char *base_dir;
 274        int base_dir_len;
 275        unsigned force:1,
 276                 quiet:1,
 277                 not_new:1,
 278                 refresh_cache:1;
 279};
 280
 281extern int checkout_entry(struct cache_entry *ce, struct checkout *state);
 282
 283extern struct alternate_object_database {
 284        struct alternate_object_database *next;
 285        char *name;
 286        char base[0]; /* more */
 287} *alt_odb_list;
 288extern void prepare_alt_odb(void);
 289
 290extern struct packed_git {
 291        struct packed_git *next;
 292        unsigned long index_size;
 293        unsigned long pack_size;
 294        unsigned int *index_base;
 295        void *pack_base;
 296        unsigned int pack_last_used;
 297        unsigned int pack_use_cnt;
 298        unsigned char sha1[20];
 299        char pack_name[0]; /* something like ".git/objects/pack/xxxxx.pack" */
 300} *packed_git;
 301
 302struct pack_entry {
 303        unsigned int offset;
 304        unsigned char sha1[20];
 305        struct packed_git *p;
 306};
 307
 308struct ref {
 309        struct ref *next;
 310        unsigned char old_sha1[20];
 311        unsigned char new_sha1[20];
 312        struct ref *peer_ref; /* when renaming */
 313        char name[0];
 314};
 315
 316extern int git_connect(int fd[2], char *url, const char *prog);
 317extern int finish_connect(pid_t pid);
 318extern int path_match(const char *path, int nr, char **match);
 319extern int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 320                      int nr_refspec, char **refspec, int all);
 321extern int get_ack(int fd, unsigned char *result_sha1);
 322extern struct ref **get_remote_heads(int in, struct ref **list, int nr_match, char **match);
 323
 324extern struct packed_git *parse_pack_index(unsigned char *sha1);
 325extern struct packed_git *parse_pack_index_file(unsigned char *sha1, 
 326                                                char *idx_path);
 327
 328extern void prepare_packed_git(void);
 329extern void install_packed_git(struct packed_git *pack);
 330
 331extern struct packed_git *find_sha1_pack(const unsigned char *sha1, 
 332                                         struct packed_git *packs);
 333
 334extern int use_packed_git(struct packed_git *);
 335extern void unuse_packed_git(struct packed_git *);
 336extern struct packed_git *add_packed_git(char *, int);
 337extern int num_packed_objects(const struct packed_git *p);
 338extern int nth_packed_object_sha1(const struct packed_git *, int, unsigned char*);
 339extern int find_pack_entry_one(const unsigned char *, struct pack_entry *, struct packed_git *);
 340extern void *unpack_entry_gently(struct pack_entry *, char *, unsigned long *);
 341extern void packed_object_info_detail(struct pack_entry *, char *, unsigned long *, unsigned long *, int *, unsigned char *);
 342
 343/* Dumb servers support */
 344extern int update_server_info(int);
 345
 346#endif /* CACHE_H */