grep: -r no longer follows symlinks; use fts

Change -r to follow only command-line symlinks, and by default to
read only devices named on the command line.  This is a simple
way to get a more-useful behavior when searching random
directories; the idea is to use 'find' if you want something fancy.
-R acts as before and gets a new alias --dereference-recursive.
The code now uses fts internally, so it is more robust and
faster with large hierarchies.
* .gitignore: Remove lib/savedir.c, lib/savedir.h.
* tests/symlink: New file
* Makefile.boot (LIB_OBJS_core): Remove isdir.o, savedir.o.
Perhaps other changes are needed too, but I'm not sure what
this makefile is for.
* NEWS: Document changes.
* doc/grep.texi (File and Directory Selection): Likewise.
* bootstrap.conf (gnulib_modules): Remove dirent, dirname, isdir, open.
Add fstatat, fts, openat-safer.
* lib/Makefile.am (libgreputils_a_SOURCES): Remove savedir.c, savedir.h.
* lib/savedir.c, lib/savedir.h: Remove.
* po/POTFILES.in: Add lib/openat-die.c.
* src/main.c: Include fcntl-safer.h, fts_.h.  Don't include
isdir.h, savedir.h.
(struct stats, stats_base): Remove.
(long_options, usage, main): Add --dereference-recursive and
implement -r vs -R.
(filename_prefix_len, fts_options): New static vars.
(basic_fts_options, READ_COMMAND_LINE_DEVICES): New constants.
(devices): Now defaults to READ_COMMAND_LINE_DEVICES.
(reset, grep): Now takes just struct stat rather than file name and
struct stats.  All callers changed.
(fillbuf): Now takes struct stat reather than struct stats.
All callers changed.
(grep): Don't worry about recursing too deeply; fts and grepdesc
handle this now.
(is_device_mode, grepdirent, grepdesc, grep_command_line_args):
New functions.
(grepfile): New args DIRDESC, FOLLOW, COMMAND_LINE.  Remove struct stats
arg.  All callers changed.  Use openat_safer rather than open.
Use desc == STDIN_FILENO to tell whether we're reading "-".
Don't worry about EINTR when closing -- not possible, since we're
not catching signals.
* tests/Makefile.am (TESTS): Add symlink.
* tests/symlink: New file.

3 files changed, 1 insertions, 175 deletions

diff --git a/lib/Makefile.am b/lib/Makefile.am
index 04ae51ea..527c6f54 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -32,7 +32,7 @@ INCLUDES = -I.. -I$(srcdir)
 AM_CFLAGS += $(GNULIB_WARN_CFLAGS) $(WERROR_CFLAGS)
 
 libgreputils_a_SOURCES += \
-  colorize.c colorize.h savedir.c savedir.h
+  colorize.c colorize.h
 
 EXTRA_DIST += colorize-posix.c colorize-w32.c
 
diff --git a/lib/savedir.c b/lib/savedir.c
deleted file mode 100644
index 3f93c165..00000000
--- a/lib/savedir.c
+++ /dev/null
@@ -1,163 +0,0 @@
-/* savedir.c -- save the list of files in a directory in a string
-   Copyright (C) 1990, 1997-2001, 2009-2012 Free Software Foundation, Inc.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3, or (at your option)
-   any later version.
-
-   This program 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 General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software Foundation,
-   Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
-
-/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
-
-#include <config.h>
-
-#include <sys/types.h>
-#include <unistd.h>
-#include <dirent.h>
-
-#ifdef CLOSEDIR_VOID
-/* Fake a return value. */
-# define CLOSEDIR(d) (closedir (d), 0)
-#else
-# define CLOSEDIR(d) closedir (d)
-#endif
-
-#include <stdlib.h>
-#include <string.h>
-#include <fnmatch.h>
-#include "savedir.h"
-#include "xalloc.h"
-
-static char *path;
-static size_t pathlen;
-
-extern int isdir (const char *name);
-
-static int
-isdir1 (const char *dir, const char *file)
-{
-  size_t dirlen = strlen (dir);
-  size_t filelen = strlen (file);
-
-  while (dirlen && dir[dirlen - 1] == '/')
-    dirlen--;
-
-  if ((dirlen + filelen + 2) > pathlen)
-    {
-      pathlen *= 2;
-      if ((dirlen + filelen + 2) > pathlen)
-        pathlen = dirlen + filelen + 2;
-
-      path = xrealloc (path, pathlen);
-    }
-
-  memcpy (path, dir, dirlen);
-  path[dirlen] = '/';
-  strcpy (path + dirlen + 1, file);
-  return isdir (path);
-}
-
-/* Return a freshly allocated string containing the filenames
-   in directory DIR, separated by '\0' characters;
-   the end is marked by two '\0' characters in a row.
-   NAME_SIZE is the number of bytes to initially allocate
-   for the string; it will be enlarged as needed.
-   Return NULL if DIR cannot be opened or if out of memory. */
-char *
-savedir (const char *dir, off_t name_size, struct exclude *included_patterns,
-         struct exclude *excluded_patterns, struct exclude *excluded_directory_patterns )
-{
-  DIR *dirp;
-  struct dirent *dp;
-  char *name_space;
-  char *namep;
-
-  dirp = opendir (dir);
-  if (dirp == NULL)
-    return NULL;
-
-  /* Be sure name_size is at least `1' so there's room for
-     the final NUL byte.  */
-  if (name_size <= 0)
-    name_size = 1;
-
-  name_space = (char *) malloc (name_size);
-  if (name_space == NULL)
-    {
-      closedir (dirp);
-      return NULL;
-    }
-  namep = name_space;
-
-  while ((dp = readdir (dirp)) != NULL)
-    {
-      /* Skip "." and ".." (some NFS file systems' directories lack them). */
-      if (dp->d_name[0] != '.'
-          || (dp->d_name[1] != '\0'
-              && (dp->d_name[1] != '.' || dp->d_name[2] != '\0')))
-        {
-          size_t namlen = strlen (dp->d_name);
-          size_t size_needed = (namep - name_space) + namlen + 2;
-
-          if ((included_patterns || excluded_patterns)
-              && !isdir1 (dir, dp->d_name))
-            {
-              if (included_patterns
-                  && excluded_file_name (included_patterns, dp->d_name))
-                continue;
-              if (excluded_patterns
-                  && excluded_file_name (excluded_patterns, dp->d_name))
-                continue;
-            }
-
-          if ( excluded_directory_patterns
-              && isdir1 (dir, dp->d_name) )
-            {
-              if (excluded_directory_patterns
-                  && excluded_file_name (excluded_directory_patterns, dp->d_name))
-                continue;
-            }
-
-          if (size_needed > name_size)
-            {
-              char *new_name_space;
-
-              while (size_needed > name_size)
-                name_size += 1024;
-
-              new_name_space = realloc (name_space, name_size);
-              if (new_name_space == NULL)
-                {
-                  closedir (dirp);
-                  goto fail;
-                }
-              namep = new_name_space + (namep - name_space);
-              name_space = new_name_space;
-            }
-          strcpy (namep, dp->d_name);
-          namep += namlen + 1;
-        }
-    }
-  *namep = '\0';
-  if (CLOSEDIR (dirp))
-    {
-     fail:
-      free (name_space);
-      name_space = NULL;
-    }
-  if (path)
-    {
-      free (path);
-      path = NULL;
-      pathlen = 0;
-    }
-  return name_space;
-}
diff --git a/lib/savedir.h b/lib/savedir.h
deleted file mode 100644
index 00cb1a98..00000000
--- a/lib/savedir.h
+++ /dev/null
@@ -1,11 +0,0 @@
-#if !defined SAVEDIR_H_
-# define SAVEDIR_H_
-
-#include "exclude.h"
-
-extern char *
-savedir (const char *dir, off_t name_size,
-         struct exclude *, struct exclude *,
-         struct exclude *);
-
-#endif