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| | #include <ftw.h>
#include <dirent.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <limits.h>
#include <pthread.h>
struct history
{
struct history *chain;
dev_t dev;
ino_t ino;
int level;
int base;
};
#undef dirfd
#define dirfd(d) (*(int *)d)
static int do_nftw(char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags, struct history *h)
{
size_t l = strlen(path), j = l && path[l-1]=='/' ? l-1 : l;
struct stat st;
struct history new;
int type;
int r, r2;
int dfd;
int err;
struct FTW lev;
if ((flags & FTW_PHYS) ? lstat(path, &st) : stat(path, &st) < 0) {
if (!(flags & FTW_PHYS) && errno==ENOENT && !lstat(path, &st))
type = FTW_SLN;
else if (errno != EACCES) return -1;
else type = FTW_NS;
} else if (S_ISDIR(st.st_mode)) {
if (flags & FTW_DEPTH) type = FTW_DP;
else type = FTW_D;
} else if (S_ISLNK(st.st_mode)) {
if (flags & FTW_PHYS) type = FTW_SL;
else type = FTW_SLN;
} else {
type = FTW_F;
}
if ((flags & FTW_MOUNT) && h && st.st_dev != h->dev)
return 0;
new.chain = h;
new.dev = st.st_dev;
new.ino = st.st_ino;
new.level = h ? h->level+1 : 0;
new.base = j+1;
lev.level = new.level;
if (h) {
lev.base = h->base;
} else {
size_t k;
for (k=j; k && path[k]=='/'; k--);
for (; k && path[k-1]!='/'; k--);
lev.base = k;
}
if (type == FTW_D || type == FTW_DP) {
dfd = open(path, O_RDONLY);
err = errno;
if (dfd < 0 && err == EACCES) type = FTW_DNR;
if (!fd_limit) close(dfd);
}
r = 0;
if (!(flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev))) {
if ((flags & FTW_ACTIONRETVAL)) {
if (r == FTW_STOP) return FTW_STOP;
if (r == FTW_SKIP_SUBTREE) return 0;
/* other values are saved for when returning */
} else
return r;
}
for (; h; h = h->chain)
if (h->dev == st.st_dev && h->ino == st.st_ino)
return r;
if ((type == FTW_D || type == FTW_DP) && fd_limit) {
if (dfd < 0) {
errno = err;
return -1;
}
DIR *d = fdopendir(dfd);
if (d) {
struct dirent *de;
if (flags & FTW_CHDIR) {
if (!fchdir(dfd)) {
err = errno;
closedir(d);
errno = err;
return -1;
}
}
while ((de = readdir(d))) {
if (de->d_name[0] == '.'
&& (!de->d_name[1]
|| (de->d_name[1]=='.'
&& !de->d_name[2]))) continue;
if (strlen(de->d_name) >= PATH_MAX-l) {
closedir(d);
errno = ENAMETOOLONG;
return -1;
}
path[j]='/';
strcpy(path+j+1, de->d_name);
if ((r2=do_nftw(path, fn, fd_limit-1, flags, &new))) {
if ((flags & FTW_ACTIONRETVAL)
&& r2 == FTW_SKIP_SIBLINGS)
break;
closedir(d);
return r2;
}
}
closedir(d);
} else {
close(dfd);
return -1;
}
}
path[l] = 0;
if (flags & FTW_DEPTH) {
r = fn(path, &st, type, &lev);
/* ignore FTW_SKIP_SUBTREE (too late), the caller is broken */
if ((flags & FTW_ACTIONRETVAL) && r == FTW_SKIP_SUBTREE)
return 0;
}
return r;
}
int nftw(const char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags)
{
int r, cs;
size_t l;
char pathbuf[PATH_MAX+1];
int orig_dfd;
if (fd_limit <= 0) return 0;
l = strlen(path);
if (l > PATH_MAX) {
errno = ENAMETOOLONG;
return -1;
}
memcpy(pathbuf, path, l+1);
if (flags & FTW_CHDIR) {
orig_dfd = open(".", O_CLOEXEC | O_PATH);
if (orig_dfd < 0)
return -1;
}
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
r = do_nftw(pathbuf, fn, fd_limit, flags, NULL);
pthread_setcancelstate(cs, 0);
if (flags & FTW_CHDIR) {
if (!fchdir(orig_dfd))
r = -1;
int err = errno;
close(orig_dfd);
errno = err;
}
return r;
}
weak_alias(nftw, nftw64);
|