Add "__noreturn__" attribute to die() and usage()
[git/git.git] / cache.h
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
18 #include SHA1_HEADER
19 #include <zlib.h>
20
21 #if ZLIB_VERNUM < 0x1200
22 #define deflateBound(c,s) ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
23 #endif
24
25 #ifdef DT_UNKNOWN
26 #define DTYPE(de) ((de)->d_type)
27 #else
28 #define DT_UNKNOWN 0
29 #define DT_DIR 1
30 #define DT_REG 2
31 #define DT_LNK 3
32 #define DTYPE(de) DT_UNKNOWN
33 #endif
34
35 #ifdef __GNUC__
36 #define NORETURN __attribute__((__noreturn__))
37 #else
38 #define NORETURN
39 #endif
40
41 /*
42 * Environment variables transition.
43 * We accept older names for now but warn.
44 */
45 extern char *gitenv_bc(const char *);
46 #define gitenv(e) (getenv(e) ? : gitenv_bc(e))
47
48 /*
49 * Basic data structures for the directory cache
50 */
51
52 #define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
53 struct 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 */
64 struct 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 */
77 struct 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[0];
89 };
90
91 #define CE_NAMEMASK (0x0fff)
92 #define CE_STAGEMASK (0x3000)
93 #define CE_UPDATE (0x4000)
94 #define CE_STAGESHIFT 12
95
96 #define create_ce_flags(len, stage) htons((len) | ((stage) << CE_STAGESHIFT))
97 #define ce_namelen(ce) (CE_NAMEMASK & ntohs((ce)->ce_flags))
98 #define ce_size(ce) cache_entry_size(ce_namelen(ce))
99 #define ce_stage(ce) ((CE_STAGEMASK & ntohs((ce)->ce_flags)) >> CE_STAGESHIFT)
100
101 #define ce_permissions(mode) (((mode) & 0100) ? 0755 : 0644)
102 static inline unsigned int create_ce_mode(unsigned int mode)
103 {
104 if (S_ISLNK(mode))
105 return htonl(S_IFLNK);
106 return htonl(S_IFREG | ce_permissions(mode));
107 }
108
109 #define cache_entry_size(len) ((offsetof(struct cache_entry,name) + (len) + 8) & ~7)
110
111 extern struct cache_entry **active_cache;
112 extern unsigned int active_nr, active_alloc, active_cache_changed;
113
114 #define GIT_DIR_ENVIRONMENT "GIT_DIR"
115 #define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
116 #define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
117 #define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
118
119 extern char *get_object_directory(void);
120 extern char *get_index_file(void);
121
122 #define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
123
124 #define alloc_nr(x) (((x)+16)*3/2)
125
126 /* Initialize and use the cache information */
127 extern int read_cache(void);
128 extern int write_cache(int newfd, struct cache_entry **cache, int entries);
129 extern int cache_name_pos(const char *name, int namelen);
130 #define ADD_CACHE_OK_TO_ADD 1 /* Ok to add */
131 #define ADD_CACHE_OK_TO_REPLACE 2 /* Ok to replace file/directory */
132 extern int add_cache_entry(struct cache_entry *ce, int option);
133 extern int remove_cache_entry_at(int pos);
134 extern int remove_file_from_cache(char *path);
135 extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
136 extern int ce_match_stat(struct cache_entry *ce, struct stat *st);
137 extern int index_fd(unsigned char *sha1, int fd, struct stat *st);
138 extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
139
140 struct cache_file {
141 struct cache_file *next;
142 char lockfile[PATH_MAX];
143 };
144 extern int hold_index_file_for_update(struct cache_file *, const char *path);
145 extern int commit_index_file(struct cache_file *);
146 extern void rollback_index_file(struct cache_file *);
147
148 #define MTIME_CHANGED 0x0001
149 #define CTIME_CHANGED 0x0002
150 #define OWNER_CHANGED 0x0004
151 #define MODE_CHANGED 0x0008
152 #define INODE_CHANGED 0x0010
153 #define DATA_CHANGED 0x0020
154 #define TYPE_CHANGED 0x0040
155
156 /* Return a statically allocated filename matching the sha1 signature */
157 extern char *sha1_file_name(const unsigned char *sha1);
158
159 /* Read and unpack a sha1 file into memory, write memory to a sha1 file */
160 extern void * map_sha1_file(const unsigned char *sha1, unsigned long *size);
161 extern int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size);
162 extern int parse_sha1_header(char *hdr, char *type, unsigned long *sizep);
163 extern int sha1_delta_base(const unsigned char *, unsigned char *);
164 extern int sha1_file_size(const unsigned char *, unsigned long *);
165 extern void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size);
166 extern void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size);
167 extern int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
168
169 extern int check_sha1_signature(unsigned char *sha1, void *buf, unsigned long size, const char *type);
170
171 /* Read a tree into the cache */
172 extern int read_tree(void *buffer, unsigned long size, int stage);
173
174 extern int write_sha1_from_fd(const unsigned char *sha1, int fd);
175
176 extern int has_sha1_file(const unsigned char *sha1);
177
178 /* Convert to/from hex/sha1 representation */
179 extern int get_sha1(const char *str, unsigned char *sha1);
180 extern int get_sha1_hex(const char *hex, unsigned char *sha1);
181 extern char *sha1_to_hex(const unsigned char *sha1); /* static buffer result! */
182
183 /* General helper functions */
184 extern void usage(const char *err) NORETURN;
185 extern void die(const char *err, ...) NORETURN;
186 extern int error(const char *err, ...);
187
188 extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
189 extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
190
191 extern void *read_object_with_reference(const unsigned char *sha1,
192 const char *required_type,
193 unsigned long *size,
194 unsigned char *sha1_ret);
195
196 const char *show_date(unsigned long time, int timezone);
197 void parse_date(char *date, char *buf, int bufsize);
198 void datestamp(char *buf, int bufsize);
199
200 static inline void *xmalloc(size_t size)
201 {
202 void *ret = malloc(size);
203 if (!ret)
204 die("Out of memory, malloc failed");
205 return ret;
206 }
207
208 static inline void *xrealloc(void *ptr, size_t size)
209 {
210 void *ret = realloc(ptr, size);
211 if (!ret)
212 die("Out of memory, realloc failed");
213 return ret;
214 }
215
216 static inline void *xcalloc(size_t nmemb, size_t size)
217 {
218 void *ret = calloc(nmemb, size);
219 if (!ret)
220 die("Out of memory, calloc failed");
221 return ret;
222 }
223
224 struct checkout {
225 const char *base_dir;
226 int base_dir_len;
227 unsigned force:1,
228 quiet:1,
229 not_new:1,
230 refresh_cache:1;
231 };
232
233 extern int checkout_entry(struct cache_entry *ce, struct checkout *state);
234
235 #endif /* CACHE_H */