0c8880868a0b08a3a3548886e8a2ed28605d09fe
[git/git.git] / dir-iterator.c
1 #include "cache.h"
2 #include "dir.h"
3 #include "iterator.h"
4 #include "dir-iterator.h"
5
6 struct dir_iterator_level {
7 int initialized;
8
9 DIR *dir;
10
11 /*
12 * The length of the directory part of path at this level
13 * (including a trailing '/'):
14 */
15 size_t prefix_len;
16
17 /*
18 * The last action that has been taken with the current entry
19 * (needed for directories, which have to be included in the
20 * iteration and also iterated into):
21 */
22 enum {
23 DIR_STATE_ITER,
24 DIR_STATE_RECURSE
25 } dir_state;
26 };
27
28 /*
29 * The full data structure used to manage the internal directory
30 * iteration state. It includes members that are not part of the
31 * public interface.
32 */
33 struct dir_iterator_int {
34 struct dir_iterator base;
35
36 /*
37 * The number of levels currently on the stack. This is always
38 * at least 1, because when it becomes zero the iteration is
39 * ended and this struct is freed.
40 */
41 size_t levels_nr;
42
43 /* The number of levels that have been allocated on the stack */
44 size_t levels_alloc;
45
46 /*
47 * A stack of levels. levels[0] is the uppermost directory
48 * that will be included in this iteration.
49 */
50 struct dir_iterator_level *levels;
51 };
52
53 int dir_iterator_advance(struct dir_iterator *dir_iterator)
54 {
55 struct dir_iterator_int *iter =
56 (struct dir_iterator_int *)dir_iterator;
57
58 while (1) {
59 struct dir_iterator_level *level =
60 &iter->levels[iter->levels_nr - 1];
61 struct dirent *de;
62
63 if (!level->initialized) {
64 /*
65 * Note: dir_iterator_begin() ensures that
66 * path is not the empty string.
67 */
68 if (!is_dir_sep(iter->base.path.buf[iter->base.path.len - 1]))
69 strbuf_addch(&iter->base.path, '/');
70 level->prefix_len = iter->base.path.len;
71
72 level->dir = opendir(iter->base.path.buf);
73 if (!level->dir && errno != ENOENT) {
74 warning_errno("error opening directory '%s'",
75 iter->base.path.buf);
76 /* Popping the level is handled below */
77 }
78
79 level->initialized = 1;
80 } else if (S_ISDIR(iter->base.st.st_mode)) {
81 if (level->dir_state == DIR_STATE_ITER) {
82 /*
83 * The directory was just iterated
84 * over; now prepare to iterate into
85 * it.
86 */
87 level->dir_state = DIR_STATE_RECURSE;
88 ALLOC_GROW(iter->levels, iter->levels_nr + 1,
89 iter->levels_alloc);
90 level = &iter->levels[iter->levels_nr++];
91 level->initialized = 0;
92 continue;
93 } else {
94 /*
95 * The directory has already been
96 * iterated over and iterated into;
97 * we're done with it.
98 */
99 }
100 }
101
102 if (!level->dir) {
103 /*
104 * This level is exhausted (or wasn't opened
105 * successfully); pop up a level.
106 */
107 if (--iter->levels_nr == 0)
108 return dir_iterator_abort(dir_iterator);
109
110 continue;
111 }
112
113 /*
114 * Loop until we find an entry that we can give back
115 * to the caller:
116 */
117 while (1) {
118 strbuf_setlen(&iter->base.path, level->prefix_len);
119 errno = 0;
120 de = readdir(level->dir);
121
122 if (!de) {
123 /* This level is exhausted; pop up a level. */
124 if (errno) {
125 warning_errno("error reading directory '%s'",
126 iter->base.path.buf);
127 } else if (closedir(level->dir))
128 warning_errno("error closing directory '%s'",
129 iter->base.path.buf);
130
131 level->dir = NULL;
132 if (--iter->levels_nr == 0)
133 return dir_iterator_abort(dir_iterator);
134 break;
135 }
136
137 if (is_dot_or_dotdot(de->d_name))
138 continue;
139
140 strbuf_addstr(&iter->base.path, de->d_name);
141 if (lstat(iter->base.path.buf, &iter->base.st) < 0) {
142 if (errno != ENOENT)
143 warning_errno("failed to stat '%s'",
144 iter->base.path.buf);
145 continue;
146 }
147
148 /*
149 * We have to set these each time because
150 * the path strbuf might have been realloc()ed.
151 */
152 iter->base.relative_path =
153 iter->base.path.buf + iter->levels[0].prefix_len;
154 iter->base.basename =
155 iter->base.path.buf + level->prefix_len;
156 level->dir_state = DIR_STATE_ITER;
157
158 return ITER_OK;
159 }
160 }
161 }
162
163 int dir_iterator_abort(struct dir_iterator *dir_iterator)
164 {
165 struct dir_iterator_int *iter = (struct dir_iterator_int *)dir_iterator;
166
167 for (; iter->levels_nr; iter->levels_nr--) {
168 struct dir_iterator_level *level =
169 &iter->levels[iter->levels_nr - 1];
170
171 if (level->dir && closedir(level->dir)) {
172 int saved_errno = errno;
173 strbuf_setlen(&iter->base.path, level->prefix_len);
174 errno = saved_errno;
175 warning_errno("error closing directory '%s'",
176 iter->base.path.buf);
177 }
178 }
179
180 free(iter->levels);
181 strbuf_release(&iter->base.path);
182 free(iter);
183 return ITER_DONE;
184 }
185
186 struct dir_iterator *dir_iterator_begin(const char *path)
187 {
188 struct dir_iterator_int *iter = xcalloc(1, sizeof(*iter));
189 struct dir_iterator *dir_iterator = &iter->base;
190
191 if (!path || !*path)
192 BUG("empty path passed to dir_iterator_begin()");
193
194 strbuf_init(&iter->base.path, PATH_MAX);
195 strbuf_addstr(&iter->base.path, path);
196
197 ALLOC_GROW(iter->levels, 10, iter->levels_alloc);
198
199 iter->levels_nr = 1;
200 iter->levels[0].initialized = 0;
201
202 return dir_iterator;
203 }