1 #include <ftw.h>
2 #include <dirent.h>
3 #include <sys/stat.h>
4 #include <errno.h>
5 #include <unistd.h>
6 #include <string.h>
7 #include <limits.h>
8 #include <pthread.h>
9
10 struct history
11 {
12 struct history *chain;
13 dev_t dev;
14 ino_t ino;
15 int level;
16 int base;
17 };
18
19 #undef dirfd
20 #define dirfd(d) (*(int *)d)
21
do_nftw(char * path,int (* fn)(const char *,const struct stat *,int,struct FTW *),int fd_limit,int flags,struct history * h)22 static int do_nftw(char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags, struct history *h)
23 {
24 size_t l = strlen(path), j = l && path[l-1]=='/' ? l-1 : l;
25 struct stat st;
26 struct history new;
27 int type;
28 int r;
29 struct FTW lev;
30
31 if ((flags & FTW_PHYS) ? lstat(path, &st) : stat(path, &st) < 0) {
32 if (!(flags & FTW_PHYS) && errno==ENOENT && !lstat(path, &st))
33 type = FTW_SLN;
34 else if (errno != EACCES) return -1;
35 else type = FTW_NS;
36 } else if (S_ISDIR(st.st_mode)) {
37 if (access(path, R_OK) < 0) type = FTW_DNR;
38 else if (flags & FTW_DEPTH) type = FTW_DP;
39 else type = FTW_D;
40 } else if (S_ISLNK(st.st_mode)) {
41 if (flags & FTW_PHYS) type = FTW_SL;
42 else type = FTW_SLN;
43 } else {
44 type = FTW_F;
45 }
46
47 if ((flags & FTW_MOUNT) && h && st.st_dev != h->dev)
48 return 0;
49
50 new.chain = h;
51 new.dev = st.st_dev;
52 new.ino = st.st_ino;
53 new.level = h ? h->level+1 : 0;
54 new.base = j+1;
55
56 lev.level = new.level;
57 if (h) {
58 lev.base = h->base;
59 } else {
60 size_t k;
61 for (k=j; k && path[k]=='/'; k--);
62 for (; k && path[k-1]!='/'; k--);
63 lev.base = k;
64 }
65
66 if (!(flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev)))
67 return r;
68
69 for (; h; h = h->chain)
70 if (h->dev == st.st_dev && h->ino == st.st_ino)
71 return 0;
72
73 if ((type == FTW_D || type == FTW_DP) && fd_limit) {
74 DIR *d = opendir(path);
75 if (d) {
76 struct dirent *de;
77 while ((de = readdir(d))) {
78 if (de->d_name[0] == '.'
79 && (!de->d_name[1]
80 || (de->d_name[1]=='.'
81 && !de->d_name[2]))) continue;
82 if (strlen(de->d_name) >= PATH_MAX-l) {
83 errno = ENAMETOOLONG;
84 closedir(d);
85 return -1;
86 }
87 path[j]='/';
88 strcpy(path+j+1, de->d_name);
89 if ((r=do_nftw(path, fn, fd_limit-1, flags, &new))) {
90 closedir(d);
91 return r;
92 }
93 }
94 closedir(d);
95 } else if (errno != EACCES) {
96 return -1;
97 }
98 }
99
100 path[l] = 0;
101 if ((flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev)))
102 return r;
103
104 return 0;
105 }
106
nftw(const char * path,int (* fn)(const char *,const struct stat *,int,struct FTW *),int fd_limit,int flags)107 int nftw(const char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags)
108 {
109 int r, cs;
110 size_t l;
111 char pathbuf[PATH_MAX+1];
112
113 if (fd_limit <= 0) return 0;
114
115 l = strlen(path);
116 if (l > PATH_MAX) {
117 errno = ENAMETOOLONG;
118 return -1;
119 }
120 memcpy(pathbuf, path, l+1);
121
122 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
123 r = do_nftw(pathbuf, fn, fd_limit, flags, NULL);
124 pthread_setcancelstate(cs, 0);
125 return r;
126 }
127
128 weak_alias(nftw, nftw64);
129