[PATCH 3/3] Rename git-diff-tree-helper to git-diff-helper (part 2).
[git/git.git] / cache.h
CommitLineData
e83c5163
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1#ifndef CACHE_H
2#define CACHE_H
3
2dee0609 4#include <unistd.h>
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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>
bf0c6e83 11#include <string.h>
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12#include <errno.h>
13#include <sys/mman.h>
bb233d69 14#include <sys/param.h>
ccc4feb5 15#include <netinet/in.h>
e83c5163 16
cef661fc 17#include SHA1_HEADER
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18#include <zlib.h>
19
9da3acfb
ET
20#if ZLIB_VERNUM < 0x1200
21#define deflateBound(c,s) ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
22#endif
23
b6829693
ET
24#ifdef DT_UNKNOWN
25#define DTYPE(de) ((de)->d_type)
26#else
27#define DT_UNKNOWN 0
28#define DT_DIR 1
29#define DT_REG 2
a15c1c60 30#define DT_LNK 3
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31#define DTYPE(de) DT_UNKNOWN
32#endif
33
d19938ab
JH
34/*
35 * Environment variables transition.
36 * We accept older names for now but warn.
37 */
38extern char *gitenv_bc(const char *);
39#define gitenv(e) (getenv(e) ? : gitenv_bc(e))
40
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41/*
42 * Basic data structures for the directory cache
43 *
44 * NOTE NOTE NOTE! This is all in the native CPU byte format. It's
45 * not even trying to be portable. It's trying to be efficient. It's
46 * just a cache, after all.
47 */
48
49#define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
50struct cache_header {
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51 unsigned int hdr_signature;
52 unsigned int hdr_version;
53 unsigned int hdr_entries;
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54};
55
56/*
57 * The "cache_time" is just the low 32 bits of the
58 * time. It doesn't matter if it overflows - we only
59 * check it for equality in the 32 bits we save.
60 */
61struct cache_time {
62 unsigned int sec;
63 unsigned int nsec;
64};
65
66/*
67 * dev/ino/uid/gid/size are also just tracked to the low 32 bits
68 * Again - this is just a (very strong in practice) heuristic that
69 * the inode hasn't changed.
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70 *
71 * We save the fields in big-endian order to allow using the
72 * index file over NFS transparently.
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73 */
74struct cache_entry {
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75 struct cache_time ce_ctime;
76 struct cache_time ce_mtime;
77 unsigned int ce_dev;
78 unsigned int ce_ino;
79 unsigned int ce_mode;
80 unsigned int ce_uid;
81 unsigned int ce_gid;
82 unsigned int ce_size;
e83c5163 83 unsigned char sha1[20];
f5cabd13 84 unsigned short ce_flags;
59c1e249 85 char name[0];
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86};
87
95fd5bf8
LT
88#define CE_NAMEMASK (0x0fff)
89#define CE_STAGEMASK (0x3000)
aee46198 90#define CE_STAGESHIFT 12
95fd5bf8 91
aee46198
JH
92#define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
93#define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
94#define ce_size(ce) cache_entry_size(ce_namelen(ce))
95#define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
96
e4479470 97#define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
8ae0a8c5
KS
98static inline unsigned int create_ce_mode(unsigned int mode)
99{
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KS
100 if (S_ISLNK(mode))
101 return htonl(S_IFLNK);
db823d4a 102 return htonl(S_IFREG | ce_permissions(mode));
8ae0a8c5 103}
e4479470 104
aee46198 105#define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
f5cabd13 106
88355048
PB
107extern struct cache_entry **active_cache;
108extern unsigned int active_nr, active_alloc, active_cache_changed;
e83c5163 109
8ac069ac
JH
110#define GIT_DIR_ENVIRONMENT "GIT_DIR"
111#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
d19938ab 112#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
bb233d69 113#define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
bb233d69 114
8ac069ac
JH
115extern char *get_object_directory(void);
116extern char *get_index_file(void);
117
118#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
bb233d69 119
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120#define alloc_nr(x) (((x)+16)*3/2)
121
734aab75 122/* Initialize and use the cache information */
e83c5163 123extern int read_cache(void);
197ee8c9 124extern int write_cache(int newfd, struct cache_entry **cache, int entries);
eb38c22f 125extern int cache_name_pos(const char *name, int namelen);
192268c1
JH
126#define ADD_CACHE_OK_TO_ADD 1 /* Ok to add */
127#define ADD_CACHE_OK_TO_REPLACE 2 /* Ok to replace file/directory */
128extern int add_cache_entry(struct cache_entry *ce, int option);
b5af9107 129extern int remove_entry_at(int pos);
197ee8c9 130extern int remove_file_from_cache(char *path);
b5af9107 131extern int same_name(struct cache_entry *a, struct cache_entry *b);
734aab75 132extern int cache_match_stat(struct cache_entry *ce, struct stat *st);
74400e71 133extern int index_fd(unsigned char *sha1, int fd, struct stat *st);
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134
135#define MTIME_CHANGED 0x0001
136#define CTIME_CHANGED 0x0002
137#define OWNER_CHANGED 0x0004
138#define MODE_CHANGED 0x0008
139#define INODE_CHANGED 0x0010
140#define DATA_CHANGED 0x0020
8ae0a8c5 141#define TYPE_CHANGED 0x0040
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142
143/* Return a statically allocated filename matching the sha1 signature */
73134b6d 144extern char *sha1_file_name(const unsigned char *sha1);
e83c5163 145
e83c5163 146/* Read and unpack a sha1 file into memory, write memory to a sha1 file */
73134b6d 147extern void * map_sha1_file(const unsigned char *sha1, unsigned long *size);
2ade9340 148extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
73134b6d 149extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
f5b913c9 150extern int write_sha1_file(char *buf, unsigned long len, const char *type, unsigned char *return_sha1);
8237b185 151
d98b46f8 152extern int check_sha1_signature(unsigned char *sha1, void *buf, unsigned long size, const char *type);
e83c5163 153
94537c78
LT
154/* Read a tree into the cache */
155extern int read_tree(void *buffer, unsigned long size, int stage);
156
8237b185
DB
157extern int write_sha1_from_fd(const unsigned char *sha1, int fd);
158
159extern int has_sha1_file(const unsigned char *sha1);
160
e83c5163 161/* Convert to/from hex/sha1 representation */
3c249c95 162extern int get_sha1(const char *str, unsigned char *sha1);
197ee8c9
LT
163extern int get_sha1_hex(const char *hex, unsigned char *sha1);
164extern char *sha1_to_hex(const unsigned char *sha1); /* static buffer result! */
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165
166/* General helper functions */
2de381f9
PB
167extern void usage(const char *err);
168extern void die(const char *err, ...);
169extern int error(const char *err, ...);
170
79517a06 171extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
e83c5163 172
40469ee9
JH
173extern void *read_object_with_reference(const unsigned char *sha1,
174 const unsigned char *required_type,
175 unsigned long *size,
176 unsigned char *sha1_ret);
f4913f91 177
f80cd783 178const char *show_date(unsigned long time, int timezone);
ecee9d9e
ET
179void parse_date(char *date, char *buf, int bufsize);
180void datestamp(char *buf, int bufsize);
181
812666c8
CL
182static inline void *xmalloc(int size)
183{
184 void *ret = malloc(size);
185 if (!ret)
186 die("Out of memory, malloc failed");
187 return ret;
188}
189
190static inline void *xrealloc(void *ptr, int size)
191{
192 void *ret = realloc(ptr, size);
193 if (!ret)
194 die("Out of memory, realloc failed");
195 return ret;
196}
197
e83c5163 198#endif /* CACHE_H */