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Diffstat (limited to 'lib/libc/gen/opendir.c')
-rw-r--r--lib/libc/gen/opendir.c321
1 files changed, 1 insertions, 320 deletions
diff --git a/lib/libc/gen/opendir.c b/lib/libc/gen/opendir.c
index a3864b0939fc..08d9eb10eaa2 100644
--- a/lib/libc/gen/opendir.c
+++ b/lib/libc/gen/opendir.c
@@ -29,24 +29,13 @@
* SUCH DAMAGE.
*/
-#include <sys/cdefs.h>
-__SCCSID("@(#)opendir.c 8.8 (Berkeley) 5/1/95");
#include "namespace.h"
-#include <sys/param.h>
-
#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
#include "un-namespace.h"
#include "gen-private.h"
#include "telldir.h"
-static DIR * __opendir_common(int, int, bool);
-
/*
* Open a directory.
*/
@@ -54,313 +43,5 @@ DIR *
opendir(const char *name)
{
- return (__opendir2(name, DTF_HIDEW|DTF_NODUP));
-}
-
-/*
- * Open a directory with existing file descriptor.
- */
-DIR *
-fdopendir(int fd)
-{
-
- if (_fcntl(fd, F_SETFD, FD_CLOEXEC) == -1)
- return (NULL);
- return (__opendir_common(fd, DTF_HIDEW|DTF_NODUP, true));
-}
-
-DIR *
-__opendir2(const char *name, int flags)
-{
- int fd;
- DIR *dir;
- int saved_errno;
-
- if ((flags & (__DTF_READALL | __DTF_SKIPREAD)) != 0)
- return (NULL);
- if ((fd = _open(name,
- O_RDONLY | O_NONBLOCK | O_DIRECTORY | O_CLOEXEC)) == -1)
- return (NULL);
-
- dir = __opendir_common(fd, flags, false);
- if (dir == NULL) {
- saved_errno = errno;
- _close(fd);
- errno = saved_errno;
- }
- return (dir);
-}
-
-static int
-opendir_compar(const void *p1, const void *p2)
-{
-
- return (strcmp((*(const struct dirent * const *)p1)->d_name,
- (*(const struct dirent * const *)p2)->d_name));
-}
-
-/*
- * For a directory at the top of a unionfs stack, the entire directory's
- * contents are read and cached locally until the next call to rewinddir().
- * For the fdopendir() case, the initial seek position must be preserved.
- * For rewinddir(), the full directory should always be re-read from the
- * beginning.
- *
- * If an error occurs, the existing buffer and state of 'dirp' is left
- * unchanged.
- */
-bool
-_filldir(DIR *dirp, bool use_current_pos)
-{
- struct dirent **dpv;
- char *buf, *ddptr, *ddeptr;
- off_t pos;
- int fd2, incr, len, n, saved_errno, space;
-
- len = 0;
- space = 0;
- buf = NULL;
- ddptr = NULL;
-
- /*
- * Use the system page size if that is a multiple of DIRBLKSIZ.
- * Hopefully this can be a big win someday by allowing page
- * trades to user space to be done by _getdirentries().
- */
- incr = getpagesize();
- if ((incr % DIRBLKSIZ) != 0)
- incr = DIRBLKSIZ;
-
- /*
- * The strategy here is to read all the directory
- * entries into a buffer, sort the buffer, and
- * remove duplicate entries by setting the inode
- * number to zero.
- *
- * We reopen the directory because _getdirentries()
- * on a MNT_UNION mount modifies the open directory,
- * making it refer to the lower directory after the
- * upper directory's entries are exhausted.
- * This would otherwise break software that uses
- * the directory descriptor for fchdir or *at
- * functions, such as fts.c.
- */
- if ((fd2 = _openat(dirp->dd_fd, ".", O_RDONLY | O_CLOEXEC)) == -1)
- return (false);
-
- if (use_current_pos) {
- pos = lseek(dirp->dd_fd, 0, SEEK_CUR);
- if (pos == -1 || lseek(fd2, pos, SEEK_SET) == -1) {
- saved_errno = errno;
- _close(fd2);
- errno = saved_errno;
- return (false);
- }
- }
-
- do {
- /*
- * Always make at least DIRBLKSIZ bytes
- * available to _getdirentries
- */
- if (space < DIRBLKSIZ) {
- space += incr;
- len += incr;
- buf = reallocf(buf, len);
- if (buf == NULL) {
- saved_errno = errno;
- _close(fd2);
- errno = saved_errno;
- return (false);
- }
- ddptr = buf + (len - space);
- }
-
- n = _getdirentries(fd2, ddptr, space, &dirp->dd_seek);
- if (n > 0) {
- ddptr += n;
- space -= n;
- }
- if (n < 0) {
- saved_errno = errno;
- _close(fd2);
- errno = saved_errno;
- return (false);
- }
- } while (n > 0);
- _close(fd2);
-
- ddeptr = ddptr;
-
- /*
- * There is now a buffer full of (possibly) duplicate
- * names.
- */
- dirp->dd_buf = buf;
-
- /*
- * Go round this loop twice...
- *
- * Scan through the buffer, counting entries.
- * On the second pass, save pointers to each one.
- * Then sort the pointers and remove duplicate names.
- */
- for (dpv = NULL;;) {
- n = 0;
- ddptr = buf;
- while (ddptr < ddeptr) {
- struct dirent *dp;
-
- dp = (struct dirent *) ddptr;
- if ((long)dp & 03L)
- break;
- if ((dp->d_reclen <= 0) ||
- (dp->d_reclen > (ddeptr + 1 - ddptr)))
- break;
- ddptr += dp->d_reclen;
- if (dp->d_fileno) {
- if (dpv)
- dpv[n] = dp;
- n++;
- }
- }
-
- if (dpv) {
- struct dirent *xp;
-
- /*
- * This sort must be stable.
- */
- mergesort(dpv, n, sizeof(*dpv), opendir_compar);
-
- dpv[n] = NULL;
- xp = NULL;
-
- /*
- * Scan through the buffer in sort order,
- * zapping the inode number of any
- * duplicate names.
- */
- for (n = 0; dpv[n]; n++) {
- struct dirent *dp = dpv[n];
-
- if ((xp == NULL) ||
- strcmp(dp->d_name, xp->d_name)) {
- xp = dp;
- } else {
- dp->d_fileno = 0;
- }
- if (dp->d_type == DT_WHT &&
- (dirp->dd_flags & DTF_HIDEW))
- dp->d_fileno = 0;
- }
-
- free(dpv);
- break;
- } else {
- dpv = malloc((n+1) * sizeof(struct dirent *));
- if (dpv == NULL)
- break;
- }
- }
-
- dirp->dd_len = len;
- dirp->dd_size = ddptr - dirp->dd_buf;
- return (true);
-}
-
-static bool
-is_unionstack(int fd)
-{
- int unionstack;
-
- unionstack = _fcntl(fd, F_ISUNIONSTACK, 0);
- if (unionstack != -1)
- return (unionstack);
-
- /*
- * Should not happen unless running on a kernel without the op,
- * but no use rendering the system useless in such a case.
- */
- return (0);
-}
-
-/*
- * Common routine for opendir(3), __opendir2(3) and fdopendir(3).
- */
-static DIR *
-__opendir_common(int fd, int flags, bool use_current_pos)
-{
- DIR *dirp;
- int incr;
- int saved_errno;
- bool unionstack;
-
- if ((dirp = malloc(sizeof(DIR) + sizeof(struct _telldir))) == NULL)
- return (NULL);
-
- dirp->dd_buf = NULL;
- dirp->dd_fd = fd;
- dirp->dd_flags = flags;
- dirp->dd_loc = 0;
- dirp->dd_lock = NULL;
- dirp->dd_td = (struct _telldir *)((char *)dirp + sizeof(DIR));
- LIST_INIT(&dirp->dd_td->td_locq);
- dirp->dd_td->td_loccnt = 0;
- dirp->dd_compat_de = NULL;
-
- /*
- * Use the system page size if that is a multiple of DIRBLKSIZ.
- * Hopefully this can be a big win someday by allowing page
- * trades to user space to be done by _getdirentries().
- */
- incr = getpagesize();
- if ((incr % DIRBLKSIZ) != 0)
- incr = DIRBLKSIZ;
-
- /*
- * Determine whether this directory is the top of a union stack.
- */
- unionstack = false;
- if (flags & DTF_NODUP) {
- unionstack = is_unionstack(fd);
- }
-
- if (unionstack) {
- if (!_filldir(dirp, use_current_pos))
- goto fail;
- dirp->dd_flags |= __DTF_READALL;
- } else {
- dirp->dd_len = incr;
- dirp->dd_buf = malloc(dirp->dd_len);
- if (dirp->dd_buf == NULL)
- goto fail;
- if (use_current_pos) {
- /*
- * Read the first batch of directory entries
- * to prime dd_seek. This also checks if the
- * fd passed to fdopendir() is a directory.
- */
- dirp->dd_size = _getdirentries(dirp->dd_fd,
- dirp->dd_buf, dirp->dd_len, &dirp->dd_seek);
- if (dirp->dd_size < 0) {
- if (errno == EINVAL)
- errno = ENOTDIR;
- goto fail;
- }
- dirp->dd_flags |= __DTF_SKIPREAD;
- } else {
- dirp->dd_size = 0;
- dirp->dd_seek = 0;
- }
- }
-
- return (dirp);
-
-fail:
- saved_errno = errno;
- free(dirp->dd_buf);
- free(dirp);
- errno = saved_errno;
- return (NULL);
+ return (__opendir2(name, DTF_HIDEW | DTF_NODUP));
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-09 16:37:28 +0000