2
* Copyright (c) 2003-2004 Tim Kientzle
5
* Redistribution and use in source and binary forms, with or without
6
* modification, are permitted provided that the following conditions
8
* 1. Redistributions of source code must retain the above copyright
9
* notice, this list of conditions and the following disclaimer
10
* in this position and unchanged.
11
* 2. Redistributions in binary form must reproduce the above copyright
12
* notice, this list of conditions and the following disclaimer in the
13
* documentation and/or other materials provided with the distribution.
15
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
* There is a single list of "tree_entry" items that represent
29
* filesystem objects that require further attention. Non-directories
30
* are not kept in memory: they are pulled from readdir(), returned to
31
* the client, then freed as soon as possible. Any directory entry to
32
* be traversed gets pushed onto the stack.
34
* There is surprisingly little information that needs to be kept for
35
* each item on the stack. Just the name, depth (represented here as the
36
* string length of the parent directory's pathname), and some markers
37
* indicating how to get back to the parent (via chdir("..") for a
38
* regular dir or via fchdir(2) for a symlink).
53
* 3) Arbitrary logical traversals by closing/reopening intermediate fds.
57
struct tree_entry *next;
59
size_t dirname_length;
64
/* Definitions for tree_entry.flags bitmap. */
65
#define isDir 1 /* This entry is a regular directory. */
66
#define isDirLink 2 /* This entry is a symbolic link to a directory. */
67
#define needsTraversal 4 /* This entry hasn't yet been traversed. */
70
* Local data for this package.
73
struct tree_entry *stack;
82
size_t dirname_length;
92
/* Definitions for tree.flags bitmap. */
93
#define needsReturn 8 /* Marks first entry as not having been returned yet. */
94
#define hasStat 16 /* The st entry is set. */
95
#define hasLstat 32 /* The lst entry is set. */
98
#define HAVE_DIRENT_D_NAMLEN 1
99
#ifdef HAVE_DIRENT_D_NAMLEN
100
/* BSD extension; avoids need for a strlen() call. */
101
#define D_NAMELEN(dp) (dp)->d_namlen
103
#define D_NAMELEN(dp) (strlen((dp)->d_name))
108
dumpStack(struct tree *t)
110
struct tree_entry *te;
112
printf("\tbuff: %s\n", t->buff);
113
printf("\tpwd: "); fflush(stdout); system("pwd");
114
printf("\tstack:\n");
115
for (te = t->stack; te != NULL; te = te->next) {
116
printf("\t\tte->name: %s %s\n", te->name, te->flags & needsTraversal ? "" : "*");
122
* Add a directory path to the current stack.
125
tree_add(struct tree *t, const char *path)
127
struct tree_entry *te;
129
te = malloc(sizeof(*te));
130
memset(te, 0, sizeof(*te));
134
te->name = strdup(path);
135
te->flags = needsTraversal;
136
te->dirname_length = t->dirname_length;
140
* Append a name to the current path.
143
tree_append(struct tree *t, const char *name, size_t name_length)
146
t->buff[t->dirname_length] = '\0';
148
/* Resize pathname buffer as needed. */
149
while (name_length + 1 + t->dirname_length >= t->buff_length) {
151
if (t->buff_length < 1024)
152
t->buff_length = 1024;
153
t->buff = realloc(t->buff, t->buff_length);
155
t->basename = t->buff + t->dirname_length;
156
t->path_length = t->dirname_length + name_length;
157
if (t->dirname_length > 0) {
158
*t->basename++ = '/';
161
strcpy(t->basename, name);
165
* Open a directory tree for traversal.
168
tree_open(const char *path)
172
t = malloc(sizeof(*t));
173
memset(t, 0, sizeof(*t));
174
tree_append(t, path, strlen(path));
175
t->initialDirFd = open(".", O_RDONLY);
177
* During most of the traversal, items are set up and then
178
* returned immediately from tree_next(). That doesn't work
179
* for the very first entry, so we set a flag for this special
182
t->flags = needsReturn;
187
* We've finished a directory; ascend back to the parent.
190
tree_ascend(struct tree *t)
192
struct tree_entry *te;
196
if (te->flags & isDirLink) {
206
* Pop the working stack.
209
tree_pop(struct tree *t)
211
struct tree_entry *te;
215
t->dirname_length = te->dirname_length;
221
* Get the next item in the tree traversal.
224
tree_next(struct tree *t)
226
struct dirent *de = NULL;
228
/* Handle the startup case by returning the initial entry. */
229
if (t->flags & needsReturn) {
230
t->flags &= ~needsReturn;
234
while (t->stack != NULL) {
235
/* If there's an open dir, get the next entry from there. */
236
while (t->d != NULL) {
241
} else if (de->d_name[0] == '.'
242
&& de->d_name[1] == '\0') {
244
} else if (de->d_name[0] == '.'
245
&& de->d_name[1] == '.'
246
&& de->d_name[2] == '\0') {
250
* Append the path to the current path
253
tree_append(t, de->d_name, D_NAMELEN(de));
254
t->flags &= ~hasLstat;
255
t->flags &= ~hasStat;
260
/* If the current dir needs to be traversed, set it up. */
261
if (t->stack->flags & needsTraversal) {
262
tree_append(t, t->stack->name, strlen(t->stack->name));
263
t->stack->flags &= ~needsTraversal;
264
/* If it is a link, set up fd for the ascent. */
265
if (t->stack->flags & isDirLink) {
266
t->stack->fd = open(".", O_RDONLY);
268
if (t->openCount > t->maxOpenCount)
269
t->maxOpenCount = t->openCount;
271
if (chdir(t->stack->name) == 0) {
273
t->dirname_length = t->path_length;
280
/* We've done everything necessary for the top stack entry. */
288
* Called by the client to mark the directory just returned from
289
* tree_next() as needing to be visited.
292
tree_descend(struct tree *t)
294
const struct stat *s = tree_current_lstat(t);
296
if (S_ISDIR(s->st_mode)) {
297
tree_add(t, t->basename);
298
t->stack->flags |= isDir;
301
if (S_ISLNK(s->st_mode) && S_ISDIR(tree_current_stat(t)->st_mode)) {
302
tree_add(t, t->basename);
303
t->stack->flags |= isDirLink;
308
* Get the stat() data for the entry just returned from tree_next().
311
tree_current_stat(struct tree *t)
313
if (!(t->flags & hasStat)) {
314
stat(t->basename, &t->st);
321
* Get the lstat() data for the entry just returned from tree_next().
324
tree_current_lstat(struct tree *t)
326
if (!(t->flags & hasLstat)) {
327
lstat(t->basename, &t->lst);
328
t->flags |= hasLstat;
334
* Return the access path for the entry just returned from tree_next().
337
tree_current_access_path(struct tree *t)
339
return (t->basename);
343
* Return the full path for the entry just returned from tree_next().
346
tree_current_path(struct tree *t)
352
* Return the length of the path for the entry just returned from tree_next().
355
tree_current_pathlen(struct tree *t)
357
return (t->path_length);
361
* Return the nesting depth of the entry just returned from tree_next().
364
tree_current_depth(struct tree *t)
370
* Terminate the traversal and release any resources.
373
tree_close(struct tree *t)
375
/* Release anything remaining in the stack. */
376
while (t->stack != NULL)
380
/* chdir() back to where we started. */
381
if (t->initialDirFd >= 0) {
382
fchdir(t->initialDirFd);
383
close(t->initialDirFd);
384
t->initialDirFd = -1;
391
/* Main function for testing. */
394
int main(int argc, char **argv)
396
size_t max_path_len = 0;
401
struct tree *t = tree_open(*argv);
402
while (tree_next(t)) {
403
size_t path_len = tree_current_pathlen(t);
404
int depth = tree_current_depth(t);
405
if (path_len > max_path_len)
406
max_path_len = path_len;
407
if (depth > max_depth)
409
printf("%s\n", tree_current_path(t));
410
if (S_ISDIR(tree_current_lstat(t)->st_mode))
411
tree_descend(t); /* Descend into every dir. */
414
printf("Max path length: %d\n", max_path_len);
415
printf("Max depth: %d\n", max_depth);
416
printf("Final open count: %d\n", t->openCount);
417
printf("Max open count: %d\n", t->maxOpenCount);
added
removed
src/libarchive/examples/minitar/tree.c
