1 #include <ftw.h> 2 #include <dirent.h> 3 #include <fcntl.h> 4 #include <sys/stat.h> 5 #include <errno.h> 6 #include <unistd.h> 7 #include <string.h> 8 #include <limits.h> 9 #include <pthread.h> 10 11 struct history 12 { 13 struct history *chain; 14 dev_t dev; 15 ino_t ino; 16 int level; 17 int base; 18 }; 19 20 #undef dirfd 21 #define dirfd(d) (*(int *)d) 22 23 static int do_nftw(char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags, struct history *h) 24 { 25 size_t l = strlen(path), j = l && path[l-1]=='/' ? l-1 : l; 26 struct stat st; 27 struct history new; 28 int type; 29 int r; 30 int dfd; 31 int err; 32 struct FTW lev; 33 34 if ((flags & FTW_PHYS) ? lstat(path, &st) : stat(path, &st) < 0) { 35 if (!(flags & FTW_PHYS) && errno==ENOENT && !lstat(path, &st)) 36 type = FTW_SLN; 37 else if (errno != EACCES) return -1; 38 else type = FTW_NS; 39 } else if (S_ISDIR(st.st_mode)) { 40 if (flags & FTW_DEPTH) type = FTW_DP; 41 else type = FTW_D; 42 } else if (S_ISLNK(st.st_mode)) { 43 if (flags & FTW_PHYS) type = FTW_SL; 44 else type = FTW_SLN; 45 } else { 46 type = FTW_F; 47 } 48 49 if ((flags & FTW_MOUNT) && h && st.st_dev != h->dev) 50 return 0; 51 52 new.chain = h; 53 new.dev = st.st_dev; 54 new.ino = st.st_ino; 55 new.level = h ? h->level+1 : 0; 56 new.base = j+1; 57 58 lev.level = new.level; 59 if (h) { 60 lev.base = h->base; 61 } else { 62 size_t k; 63 for (k=j; k && path[k]=='/'; k--); 64 for (; k && path[k-1]!='/'; k--); 65 lev.base = k; 66 } 67 68 if (type == FTW_D || type == FTW_DP) { 69 dfd = open(path, O_RDONLY); 70 err = errno; 71 if (dfd < 0 && err == EACCES) type = FTW_DNR; 72 if (!fd_limit) close(dfd); 73 } 74 75 if (!(flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev))) 76 return r; 77 78 for (; h; h = h->chain) 79 if (h->dev == st.st_dev && h->ino == st.st_ino) 80 return 0; 81 82 if ((type == FTW_D || type == FTW_DP) && fd_limit) { 83 if (dfd < 0) { 84 errno = err; 85 return -1; 86 } 87 { 88 DIR *d = fdopendir(dfd); 89 if (d) { 90 struct dirent *de; 91 while ((de = readdir(d))) { 92 if (de->d_name[0] == '.' 93 && (!de->d_name[1] 94 || (de->d_name[1]=='.' 95 && !de->d_name[2]))) continue; 96 if (strlen(de->d_name) >= PATH_MAX-l) { 97 errno = ENAMETOOLONG; 98 closedir(d); 99 return -1; 100 } 101 path[j]='/'; 102 strcpy(path+j+1, de->d_name); 103 if ((r=do_nftw(path, fn, fd_limit-1, flags, &new))) { 104 closedir(d); 105 return r; 106 } 107 } 108 closedir(d); 109 } else { 110 close(dfd); 111 return -1; 112 } 113 } 114 } 115 116 path[l] = 0; 117 if ((flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev))) 118 return r; 119 120 return 0; 121 } 122 123 int nftw(const char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags) 124 { 125 int r, cs; 126 size_t l; 127 char pathbuf[PATH_MAX+1]; 128 129 if (fd_limit <= 0) return 0; 130 131 l = strlen(path); 132 if (l > PATH_MAX) { 133 errno = ENAMETOOLONG; 134 return -1; 135 } 136 memcpy(pathbuf, path, l+1); 137 138 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs); 139 r = do_nftw(pathbuf, fn, fd_limit, flags, NULL); 140 pthread_setcancelstate(cs, 0); 141 return r; 142 } 143