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-rw-r--r--include/dirent.h2
-rw-r--r--sysdeps/unix/sysv/linux/Makefile2
-rw-r--r--sysdeps/unix/sysv/linux/alpha/bits/dirent.h3
-rw-r--r--sysdeps/unix/sysv/linux/bits/dirent.h4
-rw-r--r--sysdeps/unix/sysv/linux/closedir.c4
-rw-r--r--sysdeps/unix/sysv/linux/dirstream.h9
-rw-r--r--sysdeps/unix/sysv/linux/opendir.c3
-rw-r--r--sysdeps/unix/sysv/linux/readdir.c21
-rw-r--r--sysdeps/unix/sysv/linux/readdir64.c11
-rw-r--r--sysdeps/unix/sysv/linux/rewinddir.c5
-rw-r--r--sysdeps/unix/sysv/linux/seekdir.c30
-rw-r--r--sysdeps/unix/sysv/linux/telldir.c36
-rw-r--r--sysdeps/unix/sysv/linux/telldir.h70
-rw-r--r--sysdeps/unix/sysv/linux/tst-opendir-lfs.c2
-rw-r--r--sysdeps/unix/sysv/linux/tst-opendir.c145
15 files changed, 329 insertions, 18 deletions
diff --git a/include/dirent.h b/include/dirent.h
index d7567f5e86..17827176ba 100644
--- a/include/dirent.h
+++ b/include/dirent.h
@@ -1,8 +1,8 @@
 #ifndef _DIRENT_H
+# include <dirent/dirent.h>
 # ifndef _ISOMAC
 #  include <dirstream.h>
 # endif
-# include <dirent/dirent.h>
 # ifndef _ISOMAC
 # include <sys/stat.h>
 # include <stdbool.h>
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 415aa1f14d..d5b6e26e76 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -574,6 +574,8 @@ sysdep_routines += \
 
 tests += \
   tst-getdents64 \
+  tst-opendir \
+  tst-opendir-lfs \
   tst-readdir64-compat \
   # tests
 endif # $(subdir) == dirent
diff --git a/sysdeps/unix/sysv/linux/alpha/bits/dirent.h b/sysdeps/unix/sysv/linux/alpha/bits/dirent.h
index c8a0cfe93f..586d75586a 100644
--- a/sysdeps/unix/sysv/linux/alpha/bits/dirent.h
+++ b/sysdeps/unix/sysv/linux/alpha/bits/dirent.h
@@ -54,4 +54,7 @@ struct dirent64
 /* Inform libc code that these two types are effectively identical.  */
 #define _DIRENT_MATCHES_DIRENT64	1
 
+/* alpha 'long int' is enough to handle off64_t.  */
+#define _DIRENT_OFFSET_TRANSLATION	0
+
 #endif /* bits/dirent.h */
diff --git a/sysdeps/unix/sysv/linux/bits/dirent.h b/sysdeps/unix/sysv/linux/bits/dirent.h
index ab34d986ff..bb02dcb70a 100644
--- a/sysdeps/unix/sysv/linux/bits/dirent.h
+++ b/sysdeps/unix/sysv/linux/bits/dirent.h
@@ -57,3 +57,7 @@ struct dirent64
 #else
 # define _DIRENT_MATCHES_DIRENT64	0
 #endif
+
+/* The telldir function returns long int, which may not be large enough to
+   store off64_t values.  In this case, translation is required.  */
+#define _DIRENT_OFFSET_TRANSLATION (LONG_WIDTH < 64)
diff --git a/sysdeps/unix/sysv/linux/closedir.c b/sysdeps/unix/sysv/linux/closedir.c
index f1c2608642..9585a6ca3a 100644
--- a/sysdeps/unix/sysv/linux/closedir.c
+++ b/sysdeps/unix/sysv/linux/closedir.c
@@ -47,6 +47,10 @@ __closedir (DIR *dirp)
   __libc_lock_fini (dirp->lock);
 #endif
 
+#if _DIRENT_OFFSET_TRANSLATION
+  dirstream_loc_clear (&dirp->locs);
+#endif
+
   free ((void *) dirp);
 
   return __close_nocancel (fd);
diff --git a/sysdeps/unix/sysv/linux/dirstream.h b/sysdeps/unix/sysv/linux/dirstream.h
index 3cb313b410..27193b54dc 100644
--- a/sysdeps/unix/sysv/linux/dirstream.h
+++ b/sysdeps/unix/sysv/linux/dirstream.h
@@ -21,6 +21,7 @@
 #include <sys/types.h>
 
 #include <libc-lock.h>
+#include <telldir.h>
 
 /* Directory stream type.
 
@@ -37,10 +38,16 @@ struct __dirstream
     size_t size;		/* Total valid data in the block.  */
     size_t offset;		/* Current offset into the block.  */
 
-    off_t filepos;		/* Position of next entry to read.  */
+    off64_t filepos;		/* Position of next entry to read.  */
 
     int errcode;		/* Delayed error code.  */
 
+#if _DIRENT_OFFSET_TRANSLATION
+    /* The array is used to map long to off_64 for telldir/seekdir for ABIs
+       where long can not fully represend a LFS off_t value.  */
+    struct dirstream_loc_t locs;
+#endif
+
     /* Directory block.  We must make sure that this block starts
        at an address that is aligned adequately enough to store
        dirent entries.  Using the alignment of "void *" is not
diff --git a/sysdeps/unix/sysv/linux/opendir.c b/sysdeps/unix/sysv/linux/opendir.c
index 4336196a4d..3e2caabb9d 100644
--- a/sysdeps/unix/sysv/linux/opendir.c
+++ b/sysdeps/unix/sysv/linux/opendir.c
@@ -129,6 +129,9 @@ __alloc_dir (int fd, bool close_fd, int flags,
   dirp->offset = 0;
   dirp->filepos = 0;
   dirp->errcode = 0;
+#if _DIRENT_OFFSET_TRANSLATION
+  dirstream_loc_init (&dirp->locs);
+#endif
 
   return dirp;
 }
diff --git a/sysdeps/unix/sysv/linux/readdir.c b/sysdeps/unix/sysv/linux/readdir.c
index 72ba895afe..9577c2ebab 100644
--- a/sysdeps/unix/sysv/linux/readdir.c
+++ b/sysdeps/unix/sysv/linux/readdir.c
@@ -75,25 +75,22 @@ __readdir_unlocked (DIR *dirp)
       size_t new_reclen = ALIGN_UP (old_reclen - size_diff,
 				    _Alignof (struct dirent));
 
-      if (!in_ino_t_range (inp->dp64.d_ino)
-	  || !in_off_t_range (inp->dp64.d_off))
+      /* telldir can not return an error, so preallocate a map entry if
+	 d_off can not be used directly.  */
+      if (telldir_need_dirstream (inp->dp64.d_off))
 	{
-	  /* Overflow.  If there was at least one entry before this one,
-	     return them without error, otherwise signal overflow.  */
-	  if (dirp->offset != 0)
-	    {
-	      __lseek64 (dirp->fd, dirp->offset, SEEK_SET);
-	      outp = (void*)(outp->b - dirp->data);
-	      return &outp->dp;
-	    }
-	  __set_errno (EOVERFLOW);
-	  return NULL;
+	  dirstream_loc_add (&dirp->locs, inp->dp64.d_off);
+	  if (dirstream_loc_has_failed (&dirp->locs))
+	    return NULL;
 	}
 
       /* Copy the data from INP and access only OUTP.  */
       const uint64_t d_ino = inp->dp64.d_ino;
       const int64_t d_off = inp->dp64.d_off;
       const uint8_t d_type = inp->dp64.d_type;
+      /* This will clamp both d_off and d_ino values, which is required to
+	 avoid return EOVERFLOW.  The lelldir/seekdir uses the 'locs' value
+	 if the value overflows.  */
       outp->dp.d_ino = d_ino;
       outp->dp.d_off = d_off;
       outp->dp.d_reclen = new_reclen;
diff --git a/sysdeps/unix/sysv/linux/readdir64.c b/sysdeps/unix/sysv/linux/readdir64.c
index db1c6214d8..306728b27b 100644
--- a/sysdeps/unix/sysv/linux/readdir64.c
+++ b/sysdeps/unix/sysv/linux/readdir64.c
@@ -68,6 +68,17 @@ __readdir64 (DIR *dirp)
   dirp->offset += dp->d_reclen;
   dirp->filepos = dp->d_off;
 
+#if _DIRENT_OFFSET_TRANSLATION
+  /* telldir can not return an error, so preallocate a map entry if
+     d_off can not be used directly.  */
+  if (telldir_need_dirstream (dp->d_off))
+    {
+      dirstream_loc_add (&dirp->locs, dp->d_off);
+      if (dirstream_loc_has_failed (&dirp->locs))
+	dp = NULL;
+    }
+#endif
+
 #if IS_IN (libc)
   __libc_lock_unlock (dirp->lock);
 #endif
diff --git a/sysdeps/unix/sysv/linux/rewinddir.c b/sysdeps/unix/sysv/linux/rewinddir.c
index c0fb7aa765..1b158a584f 100644
--- a/sysdeps/unix/sysv/linux/rewinddir.c
+++ b/sysdeps/unix/sysv/linux/rewinddir.c
@@ -33,6 +33,11 @@ __rewinddir (DIR *dirp)
   dirp->offset = 0;
   dirp->size = 0;
   dirp->errcode = 0;
+
+#ifndef __LP64__
+  dirstream_loc_clear (&dirp->locs);
+#endif
+
 #if IS_IN (libc)
   __libc_lock_unlock (dirp->lock);
 #endif
diff --git a/sysdeps/unix/sysv/linux/seekdir.c b/sysdeps/unix/sysv/linux/seekdir.c
index 939ccc4447..38b632964a 100644
--- a/sysdeps/unix/sysv/linux/seekdir.c
+++ b/sysdeps/unix/sysv/linux/seekdir.c
@@ -22,14 +22,36 @@
 #include <dirstream.h>
 
 /* Seek to position POS in DIRP.  */
-/* XXX should be __seekdir ? */
 void
 seekdir (DIR *dirp, long int pos)
 {
+  off64_t filepos;
+
   __libc_lock_lock (dirp->lock);
-  (void) __lseek (dirp->fd, pos, SEEK_SET);
-  dirp->size = 0;
+
+#if _DIRENT_OFFSET_TRANSLATION
+  union dirstream_packed dsp = { .l = pos };
+  if (dsp.p.is_packed == 1)
+    filepos = dsp.p.info;
+  else
+    {
+      size_t index = dsp.p.info;
+
+      if (index >= dirstream_loc_size (&dirp->locs))
+	{
+	  __libc_lock_unlock (dirp->lock);
+	  return;
+	}
+      filepos = *dirstream_loc_at (&dirp->locs, index);
+    }
+#else
+  filepos = pos;
+#endif
+
+  __lseek64 (dirp->fd, filepos, SEEK_SET);
+  dirp->filepos = filepos;
   dirp->offset = 0;
-  dirp->filepos = pos;
+  dirp->size = 0;
+
   __libc_lock_unlock (dirp->lock);
 }
diff --git a/sysdeps/unix/sysv/linux/telldir.c b/sysdeps/unix/sysv/linux/telldir.c
index 1e5c129e9f..1ac4fce50c 100644
--- a/sysdeps/unix/sysv/linux/telldir.c
+++ b/sysdeps/unix/sysv/linux/telldir.c
@@ -15,9 +15,12 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <stdio.h>
+#include <assert.h>
 #include <dirent.h>
 
 #include <dirstream.h>
+#include <telldir.h>
 
 /* Return the current position of DIRP.  */
 long int
@@ -26,7 +29,40 @@ telldir (DIR *dirp)
   long int ret;
 
   __libc_lock_lock (dirp->lock);
+
+#if _DIRENT_OFFSET_TRANSLATION
+  /* If the directory position fits in the packet structure, returns it.
+     Otherwise, check if the position is already been recorded in the
+     dynamic array.  If not, add the new record.  */
+
+  union dirstream_packed dsp;
+
+  if (!telldir_need_dirstream (dirp->filepos))
+    {
+      dsp.p.is_packed = 1;
+      dsp.p.info = dirp->filepos;
+    }
+  else
+    {
+      dsp.l = -1;
+
+      size_t i;
+      for (i = 0; ;i++)
+	{
+	  /* It should be pre-allocated on readdir.  */
+	  assert (i < dirstream_loc_size (&dirp->locs));
+	  if (*dirstream_loc_at (&dirp->locs, i) == dirp->filepos)
+	    break;
+	}
+
+      dsp.p.is_packed = 0;
+      dsp.p.info = i;
+    }
+
+  ret = dsp.l;
+#else
   ret = dirp->filepos;
+#endif
   __libc_lock_unlock (dirp->lock);
 
   return ret;
diff --git a/sysdeps/unix/sysv/linux/telldir.h b/sysdeps/unix/sysv/linux/telldir.h
new file mode 100644
index 0000000000..7772129db0
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/telldir.h
@@ -0,0 +1,70 @@
+/* Linux internal telldir definitions.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _TELLDIR_H
+#define _TELLDIR_H 1
+
+#include <dirent.h>
+
+#if _DIRENT_OFFSET_TRANSLATION
+
+_Static_assert (sizeof (long int) < sizeof (__off64_t),
+		"sizeof (long int) >= sizeof (__off64_t)");
+
+# include <intprops.h>
+
+/* On platforms where 'long int' is smaller than 'off64_t' this is how the
+   returned value is encoded and returned by 'telldir'.  If the directory
+   offset can be enconded in 31 bits it is returned in the 'info' member
+   with 'is_packed' set to 1.
+
+   Otherwise, the 'info' member describes an index in a dynamic array at
+   'DIR' structure.  */
+
+union dirstream_packed
+{
+  long int l;
+  struct
+  {
+    unsigned long int is_packed:1;
+    unsigned long int info:31;
+  } p;
+};
+
+/* telldir maintains a list of offsets that describe the obtained diretory
+   position if it can fit this information in the returned 'dirstream_packed'
+   struct.  */
+
+# define DYNARRAY_STRUCT  dirstream_loc_t
+# define DYNARRAY_ELEMENT off64_t
+# define DYNARRAY_PREFIX  dirstream_loc_
+# include <malloc/dynarray-skeleton.c>
+
+static __always_inline bool
+telldir_need_dirstream (__off64_t d_off)
+{
+  return ! (TYPE_MINIMUM (off_t) <= d_off && d_off <= TYPE_MAXIMUM (off_t));
+}
+#else
+
+_Static_assert (sizeof (long int) == sizeof (off64_t),
+		"sizeof (long int) != sizeof (off64_t)");
+
+#endif /* __LP64__  */
+
+#endif /* _TELLDIR_H  */
diff --git a/sysdeps/unix/sysv/linux/tst-opendir-lfs.c b/sysdeps/unix/sysv/linux/tst-opendir-lfs.c
new file mode 100644
index 0000000000..1de1891fb4
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-opendir-lfs.c
@@ -0,0 +1,2 @@
+#define _FILE_OFFSET_BITS 64
+#include "tst-opendir.c"
diff --git a/sysdeps/unix/sysv/linux/tst-opendir.c b/sysdeps/unix/sysv/linux/tst-opendir.c
new file mode 100644
index 0000000000..216ecf123f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tst-opendir.c
@@ -0,0 +1,145 @@
+/* Check multiple telldir and seekdir.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <dirent.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <support/check.h>
+#include <support/support.h>
+#include <support/temp_file.h>
+#include <support/xunistd.h>
+
+/* Some filesystems returns an arbitrary value for d_off direnty entry (ext4
+   for instance, where the value is an internal hash key).  The idea of create
+   a large number of file is to try trigger a overflow d_off value in a entry
+   to check if telldir/seekdir does work corretly in such case.  */
+static const char *dirname;
+/* The 2 extra files are '.' and '..'.  */
+static const size_t nfiles = (1<<14) + 2;
+
+static inline bool
+in_ino_t_range (ino64_t v)
+{
+  ino_t s = v;
+  return s == v;
+}
+
+static inline bool
+in_off_t_range (off64_t v)
+{
+  off_t s = v;
+  return s == v;
+}
+
+static void
+do_prepare (int argc, char *argv[])
+{
+  dirname = support_create_temp_directory ("tst-opendir-nolfs-");
+
+  for (size_t i = 0; i < nfiles - 2; i++)
+    {
+      int fd = create_temp_file_in_dir ("tempfile.", dirname, NULL);
+      TEST_VERIFY_EXIT (fd > 0);
+      close (fd);
+    }
+}
+#define PREPARE do_prepare
+
+static int
+do_test (void)
+{
+  DIR *dirp = opendir (dirname);
+  TEST_VERIFY_EXIT (dirp != NULL);
+
+  long int *tdirp = xreallocarray (NULL, nfiles, sizeof (long int));
+  struct dirent **ddirp = xreallocarray (NULL, nfiles,
+					 sizeof (struct dirent *));
+
+  /* For non-LFS, the entry is skipped if it can not be converted.  */
+  int count = 0;
+  for (; count < nfiles; count++)
+    {
+      struct dirent *dp = readdir (dirp);
+      if (dp == NULL)
+	break;
+      tdirp[count] = telldir (dirp);
+      ddirp[count] = xmalloc (dp->d_reclen);
+      memcpy (ddirp[count], dp, dp->d_reclen);
+    }
+
+  closedir (dirp);
+
+  /* Check against the getdents64 syscall.  */
+  int fd = xopen (dirname, O_RDONLY | O_DIRECTORY, 0);
+  int i = 0;
+  while (true)
+    {
+      struct
+      {
+	char buffer[1024];
+	struct dirent64 pad;
+      } data;
+
+      ssize_t ret = getdents64 (fd, &data.buffer, sizeof (data.buffer));
+      if (ret < 0)
+	FAIL_EXIT1 ("getdents64: %m");
+      if (ret == 0)
+	break;
+
+      char *current = data.buffer;
+      char *end = data.buffer + ret;
+      while (current != end)
+	{
+	  struct dirent64 entry;
+          memcpy (&entry, current, sizeof (entry));
+          /* Truncate overlong strings.  */
+          entry.d_name[sizeof (entry.d_name) - 1] = '\0';
+          TEST_VERIFY (strlen (entry.d_name) < sizeof (entry.d_name) - 1);
+
+	  if (in_ino_t_range (entry.d_ino))
+	    {
+	      TEST_COMPARE_STRING (entry.d_name, ddirp[i]->d_name);
+	      TEST_COMPARE (entry.d_ino, ddirp[i]->d_ino);
+	      TEST_COMPARE (entry.d_type, ddirp[i]->d_type);
+
+	      /* Offset zero is reserved for the first entry.  */
+	      TEST_VERIFY (entry.d_off != 0);
+
+	      TEST_VERIFY_EXIT (entry.d_reclen <= end - current);
+	      i++;
+	    }
+
+	  current += entry.d_reclen;
+	}
+    }
+
+  TEST_COMPARE (count, i);
+
+  free (tdirp);
+  for (int i = 0; i < count; i++)
+    free (ddirp[i]);
+  free (ddirp);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-06-13 16:07:14 +0000