1 /*
2 * Copyright (c) 2003, 2004 Todd C. Miller <Todd.Miller@courtesan.com>
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 *
16 * Sponsored in part by the Defense Advanced Research Projects
17 * Agency (DARPA) and Air Force Research Laboratory, Air Force
18 * Materiel Command, USAF, under agreement number F39502-99-1-0512.
19 */
20
21 #include <errno.h>
22 #include <fts.h>
23 #include <ftw.h>
24 #include <sys/stat.h>
25 #include <sys/types.h>
26 #include <unistd.h>
27
28 extern "C" FTS* __fts_open(char* const*, int, int (*)(const FTSENT**, const FTSENT**));
29
do_nftw(const char * path,int (* ftw_fn)(const char *,const struct stat *,int),int (* nftw_fn)(const char *,const struct stat *,int,FTW *),int nfds,int nftw_flags)30 static int do_nftw(const char* path,
31 int (*ftw_fn)(const char*, const struct stat*, int),
32 int (*nftw_fn)(const char*, const struct stat*, int, FTW*),
33 int nfds,
34 int nftw_flags) {
35 // TODO: nfds is currently unused.
36 if (nfds < 1) {
37 errno = EINVAL;
38 return -1;
39 }
40
41 // Translate to fts_open options.
42 int fts_options = FTS_LOGICAL | FTS_COMFOLLOW | FTS_NOCHDIR;
43 if (nftw_fn) {
44 fts_options = FTS_COMFOLLOW | ((nftw_flags & FTW_PHYS) ? FTS_PHYSICAL : FTS_LOGICAL);
45 if (!(nftw_flags & FTW_CHDIR)) fts_options |= FTS_NOCHDIR;
46 if (nftw_flags & FTW_MOUNT) fts_options |= FTS_XDEV;
47 }
48 bool postorder = (nftw_flags & FTW_DEPTH) != 0;
49
50 // Call fts_open.
51 char* const paths[2] = { const_cast<char*>(path), nullptr };
52 FTS* fts = __fts_open(paths, fts_options | FTS_FOR_FTW, nullptr);
53 if (fts == nullptr) {
54 return -1;
55 }
56
57 // Translate fts_read results into ftw/nftw callbacks.
58 int error = 0;
59 FTSENT* cur;
60 while (error == 0 && (cur = fts_read(fts)) != nullptr) {
61 int fn_flag;
62 switch (cur->fts_info) {
63 case FTS_D:
64 // In the postorder case, we'll translate FTS_DP to FTW_DP later.
65 // In the can't-access case, we'll translate FTS_DNR to FTW_DNR later.
66 if (postorder || access(cur->fts_path, R_OK) == -1) continue;
67 fn_flag = FTW_D;
68 break;
69 case FTS_DC:
70 // POSIX says nftw "shall not report" directories causing loops (http://b/31152735).
71 continue;
72 case FTS_DNR:
73 fn_flag = FTW_DNR;
74 break;
75 case FTS_DP:
76 if (!postorder) continue;
77 fn_flag = FTW_DP;
78 break;
79 case FTS_F:
80 case FTS_DEFAULT:
81 fn_flag = FTW_F;
82 break;
83 case FTS_NS:
84 case FTS_NSOK:
85 fn_flag = FTW_NS;
86 break;
87 case FTS_SL:
88 fn_flag = FTW_SL;
89 break;
90 case FTS_SLNONE:
91 fn_flag = (nftw_fn != nullptr) ? FTW_SLN : FTW_NS;
92 break;
93 default:
94 error = -1;
95 continue;
96 }
97
98 // Call the appropriate function.
99 if (nftw_fn != nullptr) {
100 FTW ftw;
101 ftw.base = cur->fts_pathlen - cur->fts_namelen;
102 ftw.level = cur->fts_level;
103 error = nftw_fn(cur->fts_path, cur->fts_statp, fn_flag, &ftw);
104 } else {
105 error = ftw_fn(cur->fts_path, cur->fts_statp, fn_flag);
106 }
107 }
108
109 int saved_errno = errno;
110 if (fts_close(fts) != 0 && error == 0) {
111 error = -1;
112 } else {
113 errno = saved_errno;
114 }
115 return error;
116 }
117
ftw(const char * path,int (* ftw_fn)(const char *,const struct stat *,int),int nfds)118 int ftw(const char* path, int (*ftw_fn)(const char*, const struct stat*, int), int nfds) {
119 return do_nftw(path, ftw_fn, nullptr, nfds, 0);
120 }
121
nftw(const char * path,int (* nftw_fn)(const char *,const struct stat *,int,FTW *),int nfds,int nftw_flags)122 int nftw(const char* path, int (*nftw_fn)(const char*, const struct stat*, int, FTW*),
123 int nfds, int nftw_flags) {
124 return do_nftw(path, nullptr, nftw_fn, nfds, nftw_flags);
125 }
126