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| | #include <ftw.h>
#include <dirent.h>
#include <sys/stat.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <limits.h>
#include <pthread.h>
#include "libc.h"
struct context
{
char *path;
int (*fn)(const char *, const struct stat *, int, struct FTW *);
int fd_limit;
int flags;
size_t l;
struct stat st;
struct FTW lev;
};
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(struct context *c, struct history *h)
{
struct history new;
int type;
int r;
if ((c->flags & FTW_PHYS) ? lstat(c->path, &c->st) : stat(c->path, &c->st) < 0) {
if (!(c->flags & FTW_PHYS) && errno==ENOENT && !lstat(c->path, &c->st))
type = FTW_SLN;
else if (errno != EACCES) return -1;
else type = FTW_NS;
} else if (S_ISDIR(c->st.st_mode)) {
if (access(c->path, R_OK) < 0) type = FTW_DNR;
else if (c->flags & FTW_DEPTH) type = FTW_DP;
else type = FTW_D;
} else if (S_ISLNK(c->st.st_mode)) {
if (c->flags & FTW_PHYS) type = FTW_SL;
else type = FTW_SLN;
} else {
type = FTW_F;
}
if ((c->flags & FTW_MOUNT) && c->st.st_dev != h->dev)
return 0;
new.chain = h;
new.dev = c->st.st_dev;
new.ino = c->st.st_ino;
new.level = h->level+1;
new.base = c->l+1;
if (!(c->flags & FTW_DEPTH)) {
c->lev.level = new.level;
c->lev.base = h->base;
if ((r=c->fn(c->path, &c->st, type, &c->lev)))
return r;
}
for (; h; h = h->chain)
if (h->dev == c->st.st_dev && h->ino == c->st.st_ino)
return 0;
if ((type == FTW_D || type == FTW_DP) && c->fd_limit) {
DIR *d = opendir(c->path);
if (d) {
struct dirent *de;
while ((de = readdir(d))) {
size_t dl;
if (de->d_name[0] == '.'
&& (!de->d_name[1]
|| (de->d_name[1]=='.'
&& !de->d_name[2]))) continue;
if ((dl=strlen(de->d_name)) > PATH_MAX-new.base) {
errno = ENAMETOOLONG;
closedir(d);
return -1;
}
c->l = new.base+dl;
c->path[new.base-1]='/';
memcpy(c->path+new.base, de->d_name, dl+1);
--c->fd_limit;
r=do_nftw(c, &new);
++c->fd_limit;
if (r) {
closedir(d);
return r;
}
}
closedir(d);
} else if (errno != EACCES) {
return -1;
}
}
c->path[new.base-1]=0;
if (c->flags & FTW_DEPTH) {
c->lev.level = new.level;
c->lev.base = h->base;
if ((r=c->fn(c->path, &c->st, type, &c->lev)))
return r;
}
return 0;
}
int nftw(const char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags)
{
struct context c;
struct history h;
int r, cs;
size_t l;
char pathbuf[PATH_MAX+1];
if (fd_limit <= 0) return 0;
l = strlen(path);
while (l && path[l-1]=='/')
--l;
if (l > PATH_MAX) {
errno = ENAMETOOLONG;
return -1;
}
memcpy(pathbuf, path, l);
pathbuf[l] = 0;
h.chain = NULL;
h.dev = (dev_t)-1;
h.ino = (ino_t)-1;
h.level = -1;
h.base = l;
while (h.base && pathbuf[h.base-1]!='/')
--h.base;
c.path = pathbuf;
c.fn = fn;
c.fd_limit = fd_limit;
c.flags = flags;
c.l = l;
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
r = do_nftw(&c, &h);
pthread_setcancelstate(cs, 0);
return r;
}
LFS64(nftw);
|