7 /* We allow "recursive" symbolic refs. Only within reason, though */
10 int read_ref(const char *filename
, unsigned char *sha1
)
15 while ((fd
= open(filename
, O_RDONLY
)) >= 0) {
17 int len
= read(fd
, buffer
, sizeof(buffer
)-1);
24 while (len
&& isspace(buffer
[len
-1]))
27 if (!strncmp(buffer
, "ref:", 4)) {
34 while (len
&& isspace(*buf
))
36 filename
= git_path("%.*s", len
, buf
);
40 ret
= get_sha1_hex(buffer
, sha1
);
46 static int do_for_each_ref(const char *base
, int (*fn
)(const char *path
, const unsigned char *sha1
))
49 DIR *dir
= opendir(git_path("%s", base
));
53 int baselen
= strlen(base
);
54 char *path
= xmalloc(baselen
+ 257);
56 if (!strncmp(base
, "./", 2)) {
60 memcpy(path
, base
, baselen
);
61 if (baselen
&& base
[baselen
-1] != '/')
62 path
[baselen
++] = '/';
64 while ((de
= readdir(dir
)) != NULL
) {
65 unsigned char sha1
[20];
69 if (de
->d_name
[0] == '.')
71 namelen
= strlen(de
->d_name
);
74 memcpy(path
+ baselen
, de
->d_name
, namelen
+1);
75 if (stat(git_path("%s", path
), &st
) < 0)
77 if (S_ISDIR(st
.st_mode
)) {
78 retval
= do_for_each_ref(path
, fn
);
83 if (read_ref(git_path("%s", path
), sha1
) < 0)
85 if (!has_sha1_file(sha1
))
87 retval
= fn(path
, sha1
);
97 int head_ref(int (*fn
)(const char *path
, const unsigned char *sha1
))
99 unsigned char sha1
[20];
100 if (!read_ref(git_path("HEAD"), sha1
))
101 return fn("HEAD", sha1
);
105 int for_each_ref(int (*fn
)(const char *path
, const unsigned char *sha1
))
107 return do_for_each_ref("refs", fn
);
110 static char *ref_file_name(const char *ref
)
112 char *base
= get_refs_directory();
113 int baselen
= strlen(base
);
114 int reflen
= strlen(ref
);
115 char *ret
= xmalloc(baselen
+ 2 + reflen
);
116 sprintf(ret
, "%s/%s", base
, ref
);
120 static char *ref_lock_file_name(const char *ref
)
122 char *base
= get_refs_directory();
123 int baselen
= strlen(base
);
124 int reflen
= strlen(ref
);
125 char *ret
= xmalloc(baselen
+ 7 + reflen
);
126 sprintf(ret
, "%s/%s.lock", base
, ref
);
130 int get_ref_sha1(const char *ref
, unsigned char *sha1
)
132 const char *filename
;
134 if (check_ref_format(ref
))
136 filename
= git_path("refs/%s", ref
);
137 return read_ref(filename
, sha1
);
140 static int lock_ref_file(const char *filename
, const char *lock_filename
,
141 const unsigned char *old_sha1
)
143 int fd
= open(lock_filename
, O_WRONLY
| O_CREAT
| O_EXCL
, 0666);
144 unsigned char current_sha1
[20];
147 return error("Couldn't open lock file for %s: %s",
148 filename
, strerror(errno
));
150 retval
= read_ref(filename
, current_sha1
);
154 unlink(lock_filename
);
155 return error("Could not read the current value of %s",
158 if (memcmp(current_sha1
, old_sha1
, 20)) {
160 unlink(lock_filename
);
161 error("The current value of %s is %s",
162 filename
, sha1_to_hex(current_sha1
));
163 return error("Expected %s",
164 sha1_to_hex(old_sha1
));
169 unlink(lock_filename
);
170 return error("Unexpectedly found a value of %s for %s",
171 sha1_to_hex(current_sha1
), filename
);
177 int lock_ref_sha1(const char *ref
, const unsigned char *old_sha1
)
182 if (check_ref_format(ref
))
184 filename
= ref_file_name(ref
);
185 lock_filename
= ref_lock_file_name(ref
);
186 retval
= lock_ref_file(filename
, lock_filename
, old_sha1
);
192 static int write_ref_file(const char *filename
,
193 const char *lock_filename
, int fd
,
194 const unsigned char *sha1
)
196 char *hex
= sha1_to_hex(sha1
);
198 if (write(fd
, hex
, 40) < 40 ||
199 write(fd
, &term
, 1) < 1) {
200 error("Couldn't write %s\n", filename
);
205 rename(lock_filename
, filename
);
209 int write_ref_sha1(const char *ref
, int fd
, const unsigned char *sha1
)
216 if (check_ref_format(ref
))
218 filename
= ref_file_name(ref
);
219 lock_filename
= ref_lock_file_name(ref
);
220 retval
= write_ref_file(filename
, lock_filename
, fd
, sha1
);
226 int check_ref_format(const char *ref
)
229 if (ref
[0] == '.' || ref
[0] == '/')
231 middle
= strchr(ref
, '/');
232 if (!middle
|| !middle
[1])
234 if (strchr(middle
+ 1, '/'))
239 int write_ref_sha1_unlocked(const char *ref
, const unsigned char *sha1
)
245 if (check_ref_format(ref
))
247 filename
= ref_file_name(ref
);
248 lock_filename
= ref_lock_file_name(ref
);
249 fd
= open(lock_filename
, O_WRONLY
| O_CREAT
| O_EXCL
, 0666);
251 error("Writing %s", lock_filename
);
254 retval
= write_ref_file(filename
, lock_filename
, fd
, sha1
);