[3/3,roland/scandir] Refactor scandir/scandirat to use common tail.

Message ID 20150512225358.F32922C3AB9@topped-with-meat.com
State Committed
Headers

Commit Message

Roland McGrath May 12, 2015, 10:53 p.m. UTC
  This refactors things so that scandir uses only opendir and only scandirat
uses opendirat, so a configuration with a working opendir but no working
opendirat gets a working scandir and just no working scandirat.

If there are no objections, I'll commit this shortly.

Tested x86_64-linux-gnu and i686-linux-gnu.


Thanks,
Roland


2015-05-12  Roland McGrath  <roland@hack.frob.com>

	* dirent/scandir64-tail.c: New file.
	* dirent/Makefile (routines): Add them.
	* include/dirent.h (__scandir_tail, __scandir64_tail): Declare them.
	* dirent/scandir.c [!SCANDIR] (SCANDIRAT): Macro removed.
	[!SCANDIR] (SCANDIR_TAIL): New macro.
	(SCANDIR): Call __opendir and __scandir_tail, not __scandirat.
	* dirent/scandir64.c [!_DIRENT_MATCHES_DIRENT64]
	(SCANDIRAT): Macro removed.
	(SCANDIR_TAIL): New macro.
	* dirent/scandirat.c [!SCANDIRAT] (READDIR): Macro removed.
	[!SCANDIRAT] (SCANDIR_TAIL): New macro.
	(SCANDIRAT): Just call __opendirat and __scandir_tail.
	* dirent/scandirat64.c [!_DIRENT_MATCHES_DIRENT64]
	(READDIR): Macro removed.
	(SCANDIR_TAIL): New macro.
	* sysdeps/unix/sysv/linux/i386/scandir64.c (READDIR): Macro removed.
	(SCANDIR_TAIL): New macro.
  

Patch

diff --git a/dirent/Makefile b/dirent/Makefile
index 2a97649..551372e 100644
--- a/dirent/Makefile
+++ b/dirent/Makefile
@@ -27,7 +27,8 @@  routines	:= opendir closedir readdir readdir_r rewinddir \
 		   seekdir telldir scandir alphasort versionsort \
 		   getdents getdents64 dirfd readdir64 readdir64_r scandir64 \
 		   alphasort64 versionsort64 fdopendir \
-		   scandirat scandirat64 scandir-cancel
+		   scandirat scandirat64 \
+		   scandir-cancel scandir-tail scandir64-tail
 
 tests	   := list tst-seekdir opendir-tst1 bug-readdir1 tst-fdopendir \
 	      tst-fdopendir2 tst-scandir tst-scandir64
diff --git a/dirent/scandir-tail.c b/dirent/scandir-tail.c
new file mode 100644
index 0000000..4560834
--- /dev/null
+++ b/dirent/scandir-tail.c
@@ -0,0 +1,110 @@ 
+/* Logic guts of scandir*.
+   Copyright (C) 1992-2015 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <dirent.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <bits/libc-lock.h>
+
+#ifndef SCANDIR_TAIL
+# define SCANDIR_TAIL	__scandir_tail
+# define READDIR	__readdir
+# define DIRENT_TYPE	struct dirent
+#endif
+
+internal_function
+int
+SCANDIR_TAIL (DIR *dp,
+              DIRENT_TYPE ***namelist,
+              int (*select) (const DIRENT_TYPE *),
+              int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **))
+{
+  if (dp == NULL)
+    return -1;
+
+  int save = errno;
+  __set_errno (0);
+
+  int result;
+  struct scandir_cancel_struct c = { .dp = dp };
+  __libc_cleanup_push (&__scandir_cancel_handler, &c);
+
+  DIRENT_TYPE **v = NULL;
+  size_t vsize = 0;
+  DIRENT_TYPE *d;
+  while ((d = READDIR (dp)) != NULL)
+    {
+      if (select != NULL)
+        {
+          int selected = (*select) (d);
+
+	  /* The SELECT function might have changed errno.  It was
+	     zero before and it need to be again to make the later
+	     tests work.  */
+	  __set_errno (0);
+
+          if (!selected)
+            continue;
+        }
+      else
+        __set_errno (0);
+
+      if (__glibc_unlikely (c.cnt == vsize))
+        {
+          if (vsize == 0)
+            vsize = 10;
+          else
+            vsize *= 2;
+          DIRENT_TYPE **new = realloc (v, vsize * sizeof *v);
+          if (new == NULL)
+            break;
+          c.v = v = new;
+        }
+
+      size_t dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
+      DIRENT_TYPE *vnew = malloc (dsize);
+      if (vnew == NULL)
+        break;
+      v[c.cnt++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize);
+    }
+
+  if (__glibc_likely (errno == 0))
+    {
+      __closedir (dp);
+
+      /* Sort the list if we have a comparison function to sort with.  */
+      if (cmp != NULL)
+	qsort (v, c.cnt, sizeof *v, (__compar_fn_t) cmp);
+
+      *namelist = v;
+      result = c.cnt;
+    }
+  else
+    {
+      /* This frees everything and calls closedir.  */
+      __scandir_cancel_handler (&c);
+      result = -1;
+    }
+
+  __libc_cleanup_pop (0);
+
+  if (result >= 0)
+    __set_errno (save);
+  return result;
+}
diff --git a/dirent/scandir.c b/dirent/scandir.c
index 99c9681..c0c3f7a 100644
--- a/dirent/scandir.c
+++ b/dirent/scandir.c
@@ -24,23 +24,20 @@ 
 
 #undef  scandir64
 
-#include <fcntl.h>
-
 #ifndef SCANDIR
-# define SCANDIR scandir
-# define SCANDIRAT __scandirat
-# define DIRENT_TYPE struct dirent
+# define SCANDIR        scandir
+# define SCANDIR_TAIL   __scandir_tail
+# define DIRENT_TYPE    struct dirent
 #endif
 
 
 int
-SCANDIR (dir, namelist, select, cmp)
-     const char *dir;
-     DIRENT_TYPE ***namelist;
-     int (*select) (const DIRENT_TYPE *);
-     int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **);
+SCANDIR (const char *dir,
+	 DIRENT_TYPE ***namelist,
+	 int (*select) (const DIRENT_TYPE *),
+	 int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **))
 {
-  return SCANDIRAT (AT_FDCWD, dir, namelist, select, cmp);
+  return SCANDIR_TAIL (__opendir (dir), namelist, select, cmp);
 }
 
 #ifdef _DIRENT_MATCHES_DIRENT64
diff --git a/dirent/scandir64-tail.c b/dirent/scandir64-tail.c
new file mode 100644
index 0000000..b10dd0a
--- /dev/null
+++ b/dirent/scandir64-tail.c
@@ -0,0 +1,26 @@ 
+/* Logic guts of scandir*64.
+   Copyright (C) 2015 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <dirent.h>
+
+#ifndef _DIRENT_MATCHES_DIRENT64
+# define SCANDIR_TAIL   __scandir64_tail
+# define READDIR        __readdir64
+# define DIRENT_TYPE    struct dirent64
+# include <scandir-tail.c>
+#endif
diff --git a/dirent/scandir64.c b/dirent/scandir64.c
index d9f780f..fbb1866 100644
--- a/dirent/scandir64.c
+++ b/dirent/scandir64.c
@@ -20,10 +20,10 @@ 
 /* scandir.c defines scandir64 as an alias if _DIRENT_MATCHES_DIRENT64.  */
 #ifndef _DIRENT_MATCHES_DIRENT64
 
-#define SCANDIR scandir64
-#define SCANDIRAT scandirat64
-#define DIRENT_TYPE struct dirent64
+# define SCANDIR        scandir64
+# define SCANDIR_TAIL   __scandir64_tail
+# define DIRENT_TYPE    struct dirent64
 
-#include <dirent/scandir.c>
+# include <dirent/scandir.c>
 
 #endif
diff --git a/dirent/scandirat.c b/dirent/scandirat.c
index d7ae5e5..41725af 100644
--- a/dirent/scandirat.c
+++ b/dirent/scandirat.c
@@ -24,114 +24,20 @@ 
 
 #undef  scandirat64
 
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <bits/libc-lock.h>
-
 #ifndef SCANDIRAT
-# define SCANDIRAT __scandirat
-# define READDIR __readdir
-# define DIRENT_TYPE struct dirent
+# define SCANDIRAT	__scandirat
+# define SCANDIR_TAIL	__scandir_tail
+# define DIRENT_TYPE	struct dirent
 # define SCANDIRAT_WEAK_ALIAS
 #endif
 
-
 int
-SCANDIRAT (dfd, dir, namelist, select, cmp)
-     int dfd;
-     const char *dir;
-     DIRENT_TYPE ***namelist;
-     int (*select) (const DIRENT_TYPE *);
-     int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **);
+SCANDIRAT (int dfd, const char *dir,
+	   DIRENT_TYPE ***namelist,
+	   int (*select) (const DIRENT_TYPE *),
+	   int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **))
 {
-  DIR *dp = __opendirat (dfd, dir);
-  DIRENT_TYPE **v = NULL;
-  size_t vsize = 0;
-  struct scandir_cancel_struct c;
-  DIRENT_TYPE *d;
-  int save;
-
-  if (dp == NULL)
-    return -1;
-
-  save = errno;
-  __set_errno (0);
-
-  c.dp = dp;
-  c.v = NULL;
-  c.cnt = 0;
-  __libc_cleanup_push (__scandir_cancel_handler, &c);
-
-  while ((d = READDIR (dp)) != NULL)
-    {
-      int use_it = select == NULL;
-
-      if (! use_it)
-	{
-	  use_it = select (d);
-	  /* The select function might have changed errno.  It was
-	     zero before and it need to be again to make the latter
-	     tests work.  */
-	  __set_errno (0);
-	}
-
-      if (use_it)
-	{
-	  DIRENT_TYPE *vnew;
-	  size_t dsize;
-
-	  /* Ignore errors from select or readdir */
-	  __set_errno (0);
-
-	  if (__glibc_unlikely (c.cnt == vsize))
-	    {
-	      DIRENT_TYPE **new;
-	      if (vsize == 0)
-		vsize = 10;
-	      else
-		vsize *= 2;
-	      new = (DIRENT_TYPE **) realloc (v, vsize * sizeof (*v));
-	      if (new == NULL)
-		break;
-	      v = new;
-	      c.v = (void *) v;
-	    }
-
-	  dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
-	  vnew = (DIRENT_TYPE *) malloc (dsize);
-	  if (vnew == NULL)
-	    break;
-
-	  v[c.cnt++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize);
-	}
-    }
-
-  if (__builtin_expect (errno, 0) != 0)
-    {
-      save = errno;
-
-      while (c.cnt > 0)
-	free (v[--c.cnt]);
-      free (v);
-      c.cnt = -1;
-    }
-  else
-    {
-      /* Sort the list if we have a comparison function to sort with.  */
-      if (cmp != NULL)
-	qsort (v, c.cnt, sizeof (*v),
-	       (int (*) (const void *, const void *)) cmp);
-
-      *namelist = v;
-    }
-
-  __libc_cleanup_pop (0);
-
-  (void) __closedir (dp);
-  __set_errno (save);
-
-  return c.cnt;
+  return SCANDIR_TAIL (__opendirat (dfd, dir), namelist, select, cmp);
 }
 libc_hidden_def (SCANDIRAT)
 #ifdef SCANDIRAT_WEAK_ALIAS
diff --git a/dirent/scandirat64.c b/dirent/scandirat64.c
index fcdd1a9..e330a7b 100644
--- a/dirent/scandirat64.c
+++ b/dirent/scandirat64.c
@@ -20,10 +20,10 @@ 
 /* scandirat.c defines scandirat64 as an alias if _DIRENT_MATCHES_DIRENT64.  */
 #ifndef _DIRENT_MATCHES_DIRENT64
 
-#define SCANDIRAT scandirat64
-#define READDIR __readdir64
-#define DIRENT_TYPE struct dirent64
+# define SCANDIRAT      scandirat64
+# define SCANDIR_TAIL   __scandir64_tail
+# define DIRENT_TYPE    struct dirent64
 
-#include "scandirat.c"
+# include <scandirat.c>
 
 #endif
diff --git a/include/dirent.h b/include/dirent.h
index c50bd23..258f2d0 100644
--- a/include/dirent.h
+++ b/include/dirent.h
@@ -49,6 +49,26 @@  extern DIR *__alloc_dir (int fd, bool close_fd, int flags,
 extern __typeof (rewinddir) __rewinddir;
 
 extern void __scandir_cancel_handler (void *arg) attribute_hidden;
+extern int __scandir_tail (DIR *dp,
+			   struct dirent ***namelist,
+			   int (*select) (const struct dirent *),
+			   int (*cmp) (const struct dirent **,
+				       const struct dirent **))
+  internal_function attribute_hidden;
+#  ifdef _DIRENT_MATCHES_DIRENT64
+#   define __scandir64_tail (dp, namelist, select, cmp)         \
+  __scandir_tail (dp, (struct dirent ***) (namelist),           \
+		  (int (*) (const struct dirent *)) (select),   \
+		  (int (*) (const struct dirent **,             \
+			    const struct dirent **)) (cmp))
+#  else
+extern int __scandir64_tail (DIR *dp,
+			     struct dirent64 ***namelist,
+			     int (*select) (const struct dirent64 *),
+			     int (*cmp) (const struct dirent64 **,
+					 const struct dirent64 **))
+  internal_function attribute_hidden;
+#  endif
 
 libc_hidden_proto (__rewinddir)
 extern __typeof (scandirat) __scandirat;
diff --git a/sysdeps/unix/sysv/linux/i386/scandir64.c b/sysdeps/unix/sysv/linux/i386/scandir64.c
index 824bf84..8629078 100644
--- a/sysdeps/unix/sysv/linux/i386/scandir64.c
+++ b/sysdeps/unix/sysv/linux/i386/scandir64.c
@@ -17,22 +17,21 @@ 
 
 #include <dirent.h>
 
-#define SCANDIR __scandir64
-#define SCANDIRAT scandirat64
-#define READDIR __readdir64
-#define DIRENT_TYPE struct dirent64
+#define SCANDIR		__scandir64
+#define SCANDIR_TAIL	__scandir64_tail
+#define DIRENT_TYPE	struct dirent64
 
 #include <dirent/scandir.c>
 
-#undef SCANDIR
-#undef READDIR
-#undef DIRENT_TYPE
+#undef	SCANDIR
+#undef	SCANDIR_TAIL
+#undef	DIRENT_TYPE
 
 #include <shlib-compat.h>
 
 versioned_symbol (libc, __scandir64, scandir64, GLIBC_2_2);
 
-#if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)
+#if SHLIB_COMPAT (libc, GLIBC_2_1, GLIBC_2_2)
 # include <string.h>
 # include <errno.h>
 # include "olddirent.h"