Assume POSIX 1003.1-1988 or later for dirent.h.

* admin/CPP-DEFINES (HAVE_CLOSEDIR, HAVE_DIRENT_H): Remove.
* admin/notes/copyright: Adjust to src/ndir.h -> nt/inc/dirent.h renaming.
* configure.ac: Do not check for dirent.h or closdir.
* nt/inc/dirent.h: Rename from ../src/ndir.h, with these changes:
(struct dirent): Rename from struct direct.  All uses changed.
* nt/inc/sys/dir.h: Remove.
* src/dired.c: Assume HAVE_DIRENT_H.
(NAMLEN): Remove, replacing with ...
(dirent_namelen): New function.  All uses changed.  Use the GNU macro
_D_EXACT_NAMELEN if available, as it's faster than strlen.
(DIRENTRY): Remove, replacing all uses with 'struct dirent'.
(DIRENTRY_NONEMPTY): Remove.  All callers now assume it's nonzero.
* src/makefile.w32-in (DIR_H): Remove.  All uses replaced with
$(NT_INC)/dirent.h.
($(BLD)/w32.$(O)): Do not depend on $(SRC)/ndir.h.
* src/ndir.h: Rename to ../nt/inc/dirent.h.
* src/sysdep.h (closedir) [!HAVE_CLOSEDIR]: Remove.
Do not include <dirent.h>; no longer needed.
* src/w32.c: Include <dirent.h> rather than "ndir.h".

Fixes: debbugs:12958

6 files changed, 113 insertions, 186 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index d0f4ad6869d..5566b623cec 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,20 @@
+2012-11-23  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for dirent.h (Bug#12958).
+        * dired.c: Assume HAVE_DIRENT_H.
+        (NAMLEN): Remove, replacing with ...
+        (dirent_namelen): New function.  All uses changed.  Use the GNU macro
+        _D_EXACT_NAMELEN if available, as it's faster than strlen.
+        (DIRENTRY): Remove, replacing all uses with 'struct dirent'.
+        (DIRENTRY_NONEMPTY): Remove.  All callers now assume it's nonzero.
+        * makefile.w32-in (DIR_H): Remove.  All uses replaced with
+        $(NT_INC)/dirent.h.
+        ($(BLD)/w32.$(O)): Do not depend on $(SRC)/ndir.h.
+        * ndir.h: Rename to ../nt/inc/dirent.h.
+        * sysdep.h (closedir) [!HAVE_CLOSEDIR]: Remove.
+        Do not include <dirent.h>; no longer needed.
+        * w32.c: Include <dirent.h> rather than "ndir.h".
+
 2012-11-23  Chong Yidong  <cyd@gnu.org>
 
         * xftfont.c (xftfont_open): Remove duplicate assignment.
diff --git a/src/dired.c b/src/dired.c
index 4986f845101..3530b74ecb4 100644
--- a/src/dired.c
+++ b/src/dired.c
@@ -31,44 +31,10 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <errno.h>
 #include <unistd.h>
 
-/* The d_nameln member of a struct dirent includes the '\0' character
-   on some systems, but not on others.  What's worse, you can't tell
-   at compile-time which one it will be, since it really depends on
-   the sort of system providing the filesystem you're reading from,
-   not the system you are running on.  Paul Eggert
-   <eggert@bi.twinsun.com> says this occurs when Emacs is running on a
-   SunOS 4.1.2 host, reading a directory that is remote-mounted from a
-   Solaris 2.1 host and is in a native Solaris 2.1 filesystem.
-
-   Since applying strlen to the name always works, we'll just do that.  */
-#define NAMLEN(p) strlen (p->d_name)
-
-#ifdef HAVE_DIRENT_H
-
 #include <dirent.h>
-#define DIRENTRY struct dirent
-
-#else /* not HAVE_DIRENT_H */
-
-#include <sys/dir.h>
-#include <sys/stat.h>
-
-#define DIRENTRY struct direct
-
-extern DIR *opendir (char *);
-extern struct direct *readdir (DIR *);
-
-#endif /* HAVE_DIRENT_H */
-
 #include <filemode.h>
 #include <stat-time.h>
 
-#ifdef MSDOS
-#define DIRENTRY_NONEMPTY(p) ((p)->d_name[0] != 0)
-#else
-#define DIRENTRY_NONEMPTY(p) ((p)->d_ino)
-#endif
-
 #include "lisp.h"
 #include "systime.h"
 #include "character.h"
@@ -88,6 +54,17 @@ static Lisp_Object Qfile_attributes_lessp;
 
 static ptrdiff_t scmp (const char *, const char *, ptrdiff_t);
 
+/* Return the number of bytes in DP's name.  */
+static ptrdiff_t
+dirent_namelen (struct dirent *dp)
+{
+#ifdef _D_EXACT_NAMLEN
+  return _D_EXACT_NAMLEN (dp);
+#else
+  return strlen (dp->d_name);
+#endif
+}
+
 #ifdef WINDOWSNT
 Lisp_Object
 directory_files_internal_w32_unwind (Lisp_Object arg)
@@ -124,7 +101,7 @@ directory_files_internal (Lisp_Object directory, Lisp_Object full,
   bool needsep = 0;
   ptrdiff_t count = SPECPDL_INDEX ();
   struct gcpro gcpro1, gcpro2, gcpro3, gcpro4, gcpro5;
-  DIRENTRY *dp;
+  struct dirent *dp;
 #ifdef WINDOWSNT
   Lisp_Object w32_save = Qnil;
 #endif
@@ -209,6 +186,11 @@ directory_files_internal (Lisp_Object directory, Lisp_Object full,
   /* Loop reading blocks until EOF or error.  */
   for (;;)
     {
+      ptrdiff_t len;
+      bool wanted = 0;
+      Lisp_Object name, finalname;
+      struct gcpro gcpro1, gcpro2;
+
       errno = 0;
       dp = readdir (d);
 
@@ -225,89 +207,81 @@ directory_files_internal (Lisp_Object directory, Lisp_Object full,
       if (dp == NULL)
         break;
 
-      if (DIRENTRY_NONEMPTY (dp))
+      len = dirent_namelen (dp);
+      name = finalname = make_unibyte_string (dp->d_name, len);
+      GCPRO2 (finalname, name);
+
+      /* Note: DECODE_FILE can GC; it should protect its argument,
+         though.  */
+      name = DECODE_FILE (name);
+      len = SBYTES (name);
+
+      /* Now that we have unwind_protect in place, we might as well
+         allow matching to be interrupted.  */
+      immediate_quit = 1;
+      QUIT;
+
+      if (NILP (match)
+          || (0 <= re_search (bufp, SSDATA (name), len, 0, len, 0)))
+        wanted = 1;
+
+      immediate_quit = 0;
+
+      if (wanted)
         {
-          ptrdiff_t len;
-          bool wanted = 0;
-          Lisp_Object name, finalname;
-          struct gcpro gcpro1, gcpro2;
+          if (!NILP (full))
+            {
+              Lisp_Object fullname;
+              ptrdiff_t nbytes = len + directory_nbytes + needsep;
+              ptrdiff_t nchars;
 
-          len = NAMLEN (dp);
-          name = finalname = make_unibyte_string (dp->d_name, len);
-          GCPRO2 (finalname, name);
+              fullname = make_uninit_multibyte_string (nbytes, nbytes);
+              memcpy (SDATA (fullname), SDATA (directory),
+                      directory_nbytes);
 
-          /* Note: DECODE_FILE can GC; it should protect its argument,
-             though.  */
-          name = DECODE_FILE (name);
-          len = SBYTES (name);
+              if (needsep)
+                SSET (fullname, directory_nbytes, DIRECTORY_SEP);
 
-          /* Now that we have unwind_protect in place, we might as well
-             allow matching to be interrupted.  */
-          immediate_quit = 1;
-          QUIT;
+              memcpy (SDATA (fullname) + directory_nbytes + needsep,
+                      SDATA (name), len);
 
-          if (NILP (match)
-              || (0 <= re_search (bufp, SSDATA (name), len, 0, len, 0)))
-            wanted = 1;
+              nchars = chars_in_text (SDATA (fullname), nbytes);
 
-          immediate_quit = 0;
+              /* Some bug somewhere.  */
+              if (nchars > nbytes)
+                emacs_abort ();
 
-          if (wanted)
-            {
-              if (!NILP (full))
-                {
-                  Lisp_Object fullname;
-                  ptrdiff_t nbytes = len + directory_nbytes + needsep;
-                  ptrdiff_t nchars;
-
-                  fullname = make_uninit_multibyte_string (nbytes, nbytes);
-                  memcpy (SDATA (fullname), SDATA (directory),
-                          directory_nbytes);
-
-                  if (needsep)
-                    SSET (fullname, directory_nbytes, DIRECTORY_SEP);
-
-                  memcpy (SDATA (fullname) + directory_nbytes + needsep,
-                          SDATA (name), len);
-
-                  nchars = chars_in_text (SDATA (fullname), nbytes);
-
-                  /* Some bug somewhere.  */
-                  if (nchars > nbytes)
-                    emacs_abort ();
-
-                  STRING_SET_CHARS (fullname, nchars);
-                  if (nchars == nbytes)
-                    STRING_SET_UNIBYTE (fullname);
-
-                  finalname = fullname;
-                }
-              else
-                finalname = name;
-
-              if (attrs)
-                {
-                  /* Construct an expanded filename for the directory entry.
-                     Use the decoded names for input to Ffile_attributes.  */
-                  Lisp_Object decoded_fullname, fileattrs;
-                  struct gcpro gcpro1, gcpro2;
-
-                  decoded_fullname = fileattrs = Qnil;
-                  GCPRO2 (decoded_fullname, fileattrs);
-
-                  /* Both Fexpand_file_name and Ffile_attributes can GC.  */
-                  decoded_fullname = Fexpand_file_name (name, directory);
-                  fileattrs = Ffile_attributes (decoded_fullname, id_format);
-
-                  list = Fcons (Fcons (finalname, fileattrs), list);
-                  UNGCPRO;
-                }
-              else
-                list = Fcons (finalname, list);
+              STRING_SET_CHARS (fullname, nchars);
+              if (nchars == nbytes)
+                STRING_SET_UNIBYTE (fullname);
+
+              finalname = fullname;
             }
+          else
+            finalname = name;
 
-          UNGCPRO;
+          if (attrs)
+            {
+              /* Construct an expanded filename for the directory entry.
+                 Use the decoded names for input to Ffile_attributes.  */
+              Lisp_Object decoded_fullname, fileattrs;
+              struct gcpro gcpro1, gcpro2;
+
+              decoded_fullname = fileattrs = Qnil;
+              GCPRO2 (decoded_fullname, fileattrs);
+
+              /* Both Fexpand_file_name and Ffile_attributes can GC.  */
+              decoded_fullname = Fexpand_file_name (name, directory);
+              fileattrs = Ffile_attributes (decoded_fullname, id_format);
+
+              list = Fcons (Fcons (finalname, fileattrs), list);
+              UNGCPRO;
+            }
+          else
+            list = Fcons (finalname, list);
         }
+
+      UNGCPRO;
     }
 
   block_input ();
@@ -442,7 +416,8 @@ These are all file names in directory DIRECTORY which begin with FILE.  */)
   return file_name_completion (file, directory, 1, Qnil);
 }
 
-static int file_name_completion_stat (Lisp_Object dirname, DIRENTRY *dp, struct stat *st_addr);
+static int file_name_completion_stat (Lisp_Object dirname, struct dirent *dp,
+                                      struct stat *st_addr);
 static Lisp_Object Qdefault_directory;
 
 static Lisp_Object
@@ -499,7 +474,7 @@ file_name_completion (Lisp_Object file, Lisp_Object dirname, bool all_flag,
   /* (att3b compiler bug requires do a null comparison this way) */
   while (1)
     {
-      DIRENTRY *dp;
+      struct dirent *dp;
       ptrdiff_t len;
       bool canexclude = 0;
 
@@ -517,11 +492,10 @@ file_name_completion (Lisp_Object file, Lisp_Object dirname, bool all_flag,
 
       if (!dp) break;
 
-      len = NAMLEN (dp);
+      len = dirent_namelen (dp);
 
       QUIT;
-      if (! DIRENTRY_NONEMPTY (dp)
-          || len < SCHARS (encoded_file)
+      if (len < SCHARS (encoded_file)
           || 0 <= scmp (dp->d_name, SSDATA (encoded_file),
                         SCHARS (encoded_file)))
         continue;
@@ -806,9 +780,10 @@ scmp (const char *s1, const char *s2, ptrdiff_t len)
 }
 
 static int
-file_name_completion_stat (Lisp_Object dirname, DIRENTRY *dp, struct stat *st_addr)
+file_name_completion_stat (Lisp_Object dirname, struct dirent *dp,
+                           struct stat *st_addr)
 {
-  ptrdiff_t len = NAMLEN (dp);
+  ptrdiff_t len = dirent_namelen (dp);
   ptrdiff_t pos = SCHARS (dirname);
   int value;
   USE_SAFE_ALLOCA;
diff --git a/src/makefile.w32-in b/src/makefile.w32-in
index 9778e955677..5d0c6e72146 100644
--- a/src/makefile.w32-in
+++ b/src/makefile.w32-in
@@ -413,8 +413,6 @@ CONF_POST_H    = $(SRC)/conf_post.h \
                  $(MS_W32_H)
 CONFIG_H       = $(SRC)/config.h \
                  $(CONF_POST_H)
-DIR_H          = $(NT_INC)/sys/dir.h \
-                 $(SRC)/ndir.h
 W32GUI_H       = $(SRC)/w32gui.h \
                  $(SYSTIME_H)
 DISPEXTERN_H   = $(SRC)/dispextern.h \
@@ -714,6 +712,7 @@ $(BLD)/dired.$(O) : \
         $(SRC)/blockinput.h \
         $(SRC)/commands.h \
         $(SRC)/regex.h \
+        $(NT_INC)/dirent.h \
         $(NT_INC)/pwd.h \
         $(NT_INC)/sys/stat.h \
         $(NT_INC)/unistd.h \
@@ -722,7 +721,6 @@ $(BLD)/dired.$(O) : \
         $(CHARSET_H) \
         $(CODING_H) \
         $(CONFIG_H) \
-        $(DIR_H) \
         $(FILEMODE_H) \
         $(GRP_H) \
         $(LISP_H) \
@@ -1175,11 +1173,11 @@ $(BLD)/minibuf.$(O) : \
 
 $(BLD)/w32.$(O) : \
         $(SRC)/w32.c \
-        $(SRC)/ndir.h \
         $(SRC)/w32.h \
         $(SRC)/w32common.h \
         $(SRC)/w32heap.h \
         $(SRC)/w32select.h \
+        $(NT_INC)/dirent.h \
         $(NT_INC)/pwd.h \
         $(NT_INC)/sys/file.h \
         $(NT_INC)/sys/time.h \
diff --git a/src/ndir.h b/src/ndir.h
deleted file mode 100644
index cd7cdbe55f5..00000000000
--- a/src/ndir.h
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
-        <dir.h> -- definitions for 4.2BSD-compatible directory access
-
-        last edit:      09-Jul-1983     D A Gwyn
-
- * The code here is forced by the interface, and is not subject to
- * copyright, constituting the only possible expression of the
- * algorithm in this format.
- */
-
-#define DIRBLKSIZ       512             /* size of directory block */
-#ifdef WINDOWSNT
-#define MAXNAMLEN       255
-#else  /* not WINDOWSNT */
-#define MAXNAMLEN       15              /* maximum filename length */
-#endif /* not WINDOWSNT */
-        /* NOTE:  MAXNAMLEN must be one less than a multiple of 4 */
-
-struct direct                           /* data from readdir() */
-        {
-        long            d_ino;          /* inode number of entry */
-        unsigned short  d_reclen;       /* length of this record */
-        unsigned short  d_namlen;       /* length of string in d_name */
-        char            d_name[MAXNAMLEN+1];    /* name of file */
-        };
-
-typedef struct
-        {
-        int     dd_fd;                  /* file descriptor */
-        int     dd_loc;                 /* offset in block */
-        int     dd_size;                /* amount of valid data */
-        char    dd_buf[DIRBLKSIZ];      /* directory block */
-        }       DIR;                    /* stream data from opendir() */
-
-extern DIR              *opendir (char *);
-extern struct direct    *readdir (DIR *);
-extern void             seekdir (DIR *, long);
-extern void             closedir (DIR *);
-
-#define rewinddir( dirp )       seekdir( dirp, 0L )
-
diff --git a/src/sysdep.c b/src/sysdep.c
index 3dd19685540..bc4dc91509f 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -2220,28 +2220,6 @@ emacs_readlink (char const *filename, char initial_buf[READLINK_BUFSIZE])
                        &emacs_norealloc_allocator, careadlinkatcwd);
 }
 
-/* Directory routines for systems that don't have them. */
-
-#ifdef HAVE_DIRENT_H
-
-#include <dirent.h>
-
-#if !defined (HAVE_CLOSEDIR)
-
-int
-closedir (DIR *dirp /* stream from opendir */)
-{
-  int rtnval;
-
-  rtnval = emacs_close (dirp->dd_fd);
-  xfree (dirp);
-
-  return rtnval;
-}
-#endif /* not HAVE_CLOSEDIR */
-#endif /* HAVE_DIRENT_H */
-
-
 /* Return a struct timeval that is roughly equivalent to T.
    Use the least timeval not less than T.
    Return an extremal value if the result would overflow.  */
diff --git a/src/w32.c b/src/w32.c
index 038a442f529..c8e16dfaa94 100644
--- a/src/w32.c
+++ b/src/w32.c
@@ -179,7 +179,7 @@ typedef struct _REPARSE_DATA_BUFFER {
 #undef sendto
 
 #include "w32.h"
-#include "ndir.h"
+#include <dirent.h>
 #include "w32common.h"
 #include "w32heap.h"
 #include "w32select.h"
@@ -2448,7 +2448,7 @@ is_exec (const char * name)
    and readdir.  We can't use the procedures supplied in sysdep.c,
    so we provide them here.  */
 
-struct direct dir_static;       /* simulated directory contents */
+struct dirent dir_static;       /* simulated directory contents */
 static HANDLE dir_find_handle = INVALID_HANDLE_VALUE;
 static int    dir_is_fat;
 static char   dir_pathname[MAXPATHLEN+1];
@@ -2518,7 +2518,7 @@ closedir (DIR *dirp)
   xfree ((char *) dirp);
 }
 
-struct direct *
+struct dirent *
 readdir (DIR *dirp)
 {
   int downcase = !NILP (Vw32_downcase_file_names);
@@ -2572,7 +2572,7 @@ readdir (DIR *dirp)
       downcase = 1;     /* 8+3 aliases are returned in all caps */
     }
   dir_static.d_namlen = strlen (dir_static.d_name);
-  dir_static.d_reclen = sizeof (struct direct) - MAXNAMLEN + 3 +
+  dir_static.d_reclen = sizeof (struct dirent) - MAXNAMLEN + 3 +
     dir_static.d_namlen - dir_static.d_namlen % 4;
 
   /* If the file name in cFileName[] includes `?' characters, it means