fix up tree walking code with symlinks for acl commands

Merge of master-melb:xfs-cmds:30109a by kenmcd.

10 files changed, 200 insertions, 192 deletions

diff --git a/VERSION b/VERSION
index e862f3b..0458341 100644
--- a/VERSION
+++ b/VERSION
@@ -3,5 +3,5 @@
 #
 PKG_MAJOR=2
 PKG_MINOR=2
-PKG_REVISION=45
+PKG_REVISION=46
 PKG_BUILD=1
diff --git a/doc/CHANGES b/doc/CHANGES
index 84fd06c..1503acb 100644
--- a/doc/CHANGES
+++ b/doc/CHANGES
@@ -1,7 +1,13 @@
-2.2.46 (???)
-* Update acl.5 man page to clarify the relationship between
-  the file permissions and the *OBJ ACL entries thanks
-  to Andreas Gruenbacher.
+2.2.46 (21 November 2007)
+* From Andreas Gruenbacher:
+    * Update acl.5 man page to clarify the relationship between
+      the file permissions and the *OBJ ACL entries.
+    * In some cases, gcc does not link in functions from libmisc.a
+      unless libmisc is specified before the dynamic libraries on
+      the command line.
+    * Rip out nftw tree walking, it is broken and hopeless to fix.
+      The replacement walk_tree() function does exactly what we
+      want, and is much simpler to use.
 
 2.2.45 (11 September 2007)
 * Fix symlink handling with getfacl and setfacl, thanks to Utako Usaka.
diff --git a/getfacl/Makefile b/getfacl/Makefile
index 94e23a0..7e811c3 100644
--- a/getfacl/Makefile
+++ b/getfacl/Makefile
@@ -9,8 +9,8 @@ LTCOMMAND = getfacl
 CFILES = getfacl.c user_group.c
 HFILES = user_group.h
 
-LLDLIBS = $(LIBACL) $(LIBATTR) $(LIBMISC)
-LTDEPENDENCIES = $(LIBACL) $(LIBMISC)
+LLDLIBS = $(LIBMISC) $(LIBACL) $(LIBATTR)
+LTDEPENDENCIES = $(LIBMISC) $(LIBACL)
 
 default: $(LTCOMMAND)
 
diff --git a/getfacl/getfacl.c b/getfacl/getfacl.c
index a01e211..e0c564e 100644
--- a/getfacl/getfacl.c
+++ b/getfacl/getfacl.c
@@ -34,10 +34,10 @@
 #include <dirent.h>
 #include <libgen.h>
 #include <getopt.h>
-#include <ftw.h>
 #include <locale.h>
 #include "config.h"
 #include "user_group.h"
+#include "walk_tree.h"
 #include "misc.h"
 
 #define POSIXLY_CORRECT_STR "POSIXLY_CORRECT"
@@ -70,24 +70,22 @@ struct option long_options[] = {
 const char *progname;
 const char *cmd_line_options;
 
-int opt_recursive;  /* recurse into sub-directories? */
-int opt_walk_logical;  /* always follow symbolic links */
-int opt_walk_physical;  /* never follow symbolic links */
-int opt_print_acl = 0;
-int opt_print_default_acl = 0;
+int walk_flags = WALK_TREE_DEREFERENCE;
+int opt_print_acl;
+int opt_print_default_acl;
 int opt_strip_leading_slash = 1;
 int opt_comments = 1;  /* include comments */
-int opt_skip_base = 0;  /* skip files that only have the base entries */
-int opt_tabular = 0;  /* tabular output format (alias `showacl') */
+int opt_skip_base;  /* skip files that only have the base entries */
+int opt_tabular;  /* tabular output format (alias `showacl') */
 #if POSIXLY_CORRECT
 const int posixly_correct = 1;  /* Posix compatible behavior! */
 #else
-int posixly_correct = 0;  /* Posix compatible behavior? */
+int posixly_correct;  /* Posix compatible behavior? */
 #endif
-int had_errors = 0;
-int absolute_warning = 0;  /* Absolute path warning was issued */
+int had_errors;
+int absolute_warning;  /* Absolute path warning was issued */
 int print_options = TEXT_SOME_EFFECTIVE;
-int opt_numeric = 0;  /* don't convert id's to symbolic names */
+int opt_numeric;  /* don't convert id's to symbolic names */
 
 
 static const char *xquote(const char *str)
@@ -425,12 +423,18 @@ acl_get_file_mode(const char *path_p)
 	return acl_from_mode(st.st_mode);
 }
 
-int do_print(const char *path_p, const struct stat *st)
+int do_print(const char *path_p, const struct stat *st, int walk_flags, void *unused)
 {
 	const char *default_prefix = NULL;
 	acl_t acl = NULL, default_acl = NULL;
 	int error = 0;
 
+	if (walk_flags & WALK_TREE_FAILED) {
+		fprintf(stderr, "%s: %s: %s\n", progname, xquote(path_p),
+			strerror(errno));
+		return 1;
+	}
+
 	if (opt_print_acl) {
 		acl = acl_get_file(path_p, ACL_TYPE_ACCESS);
 		if (acl == NULL && (errno == ENOSYS || errno == ENOTSUP))
@@ -549,7 +553,7 @@ void help(void)
 "      --skip-base         skip files that only have the base entries\n"
 "  -R, --recursive         recurse into subdirectories\n"
 "  -L, --logical           logical walk, follow symbolic links\n"
-"  -P  --physical          physical walk, do not follow symbolic links\n"
+"  -P, --physical          physical walk, do not follow symbolic links\n"
 "      --tabular           use tabular output format\n"
 "      --numeric           print numeric user/group identifiers\n"
 "      --absolute-names    don't strip leading '/' in pathnames\n"));
@@ -560,75 +564,6 @@ void help(void)
 "      --help              this help text\n"));
 }
 
-
-static int __errors;
-int __do_print(const char *file, const struct stat *stat,
-               int flag, struct FTW *ftw)
-{
-	int saved_errno = errno;
-
-	/* Process the target of a symbolic link, and traverse the link,
-           only if doing a logical walk, or if the symbolic link was
-           specified on the command line. Always skip symbolic links if
-           doing a physical walk. */
-
-	if (S_ISLNK(stat->st_mode) &&
-	    (opt_walk_physical || (ftw->level > 0 && !opt_walk_logical)))
-		return 0;
-
-	if (do_print(file, stat))
-		__errors++;
-
-	if (flag == FTW_DNR && opt_recursive) {
-		/* Item is a directory which can't be read. */
-		fprintf(stderr, "%s: %s: %s\n",
-			progname, file, strerror(saved_errno));
-		return 0;
-	}
-
-	/* We also get here in non-recursive mode. In that case,
-	   return something != 0 to abort nftw. */
-
-	if (!opt_recursive)
-		return 1;
-
-	return 0;
-}
-
-char *resolve_symlinks(const char *file)
-{
-	static char buffer[4096];
-	struct stat stat;
-	char *path = NULL;
-
-	if (lstat(file, &stat) == -1)
-		return path;
-
-	if (S_ISLNK(stat.st_mode) && !opt_walk_physical)
-		path = realpath(file, buffer);
-	else
-		path = (char *)file; 	/* not a symlink, use given path */
-
-	return path;
-}
-
-int walk_tree(const char *file)
-{
-	const char *p;
-
-	__errors = 0;
-	if ((p = resolve_symlinks(file)) == NULL) {
-		fprintf(stderr, "%s: %s: %s\n", progname,
-			xquote(file), strerror(errno));
-		__errors++;
-	} else if (nftw(p, __do_print, 0, opt_walk_logical? 0 : FTW_PHYS) < 0) {
-		fprintf(stderr, "%s: %s: %s\n", progname, xquote(file),
-			strerror(errno));
-		__errors++;
-	}
-	return __errors;
-}
-
 int main(int argc, char *argv[])
 {
 	int opt;
@@ -691,21 +626,21 @@ int main(int argc, char *argv[])
 			case 'R':  /* recursive */
 				if (posixly_correct)
 					goto synopsis;
-				opt_recursive = 1;
+				walk_flags |= WALK_TREE_RECURSIVE;
 				break;
 
 			case 'L':  /* follow all symlinks */
 				if (posixly_correct)
 					goto synopsis;
-				opt_walk_logical = 1;
-				opt_walk_physical = 0;
+				walk_flags |= WALK_TREE_LOGICAL;
+				walk_flags &= ~WALK_TREE_PHYSICAL;
 				break;
 
 			case 'P':  /* skip all symlinks */
 				if (posixly_correct)
 					goto synopsis;
-				opt_walk_logical = 0;
-				opt_walk_physical = 1;
+				walk_flags |= WALK_TREE_PHYSICAL;
+				walk_flags &= ~WALK_TREE_LOGICAL;
 				break;
 
 			case 's':  /* skip files with only base entries */
@@ -762,7 +697,7 @@ int main(int argc, char *argv[])
 				if (*line == '\0')
 					continue;
 
-				had_errors += walk_tree(line);
+				had_errors += walk_tree(line, walk_flags, do_print, NULL);
 			}
 			if (!feof(stdin)) {
 				fprintf(stderr, _("%s: Standard input: %s\n"),
@@ -770,7 +705,7 @@ int main(int argc, char *argv[])
 				had_errors++;
 			}
 		} else
-			had_errors += walk_tree(argv[optind]);
+			had_errors += walk_tree(argv[optind], walk_flags, do_print, NULL);
 		optind++;
 	} while (optind < argc);
 
diff --git a/include/walk_tree.h b/include/walk_tree.h
new file mode 100644
index 0000000..9045bad
--- /dev/null
+++ b/include/walk_tree.h
@@ -0,0 +1,38 @@
+/*
+  File: walk_tree.h
+
+  Copyright (C) 2007 Andreas Gruenbacher <a.gruenbacher@computer.org>
+
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Library General Public
+  License as published by the Free Software Foundation; either
+  version 2 of the License, 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
+  Library General Public License for more details.
+
+  You should have received a copy of the GNU Library General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#ifndef __WALK_TREE_H
+#define __WALK_TREE_H
+
+#define WALK_TREE_RECURSIVE	0x1
+#define WALK_TREE_PHYSICAL	0x2
+#define WALK_TREE_LOGICAL	0x4
+#define WALK_TREE_DEREFERENCE	0x8
+
+#define WALK_TREE_SYMLINK	0x10
+#define WALK_TREE_FAILED	0x20
+
+struct stat;
+
+extern int walk_tree(const char *path, int walk_flags,
+		     int (*func)(const char *, const struct stat *, int, void *),
+		     void *arg);
+
+#endif
diff --git a/libmisc/Makefile b/libmisc/Makefile
index 9491d41..cdea6ad 100644
--- a/libmisc/Makefile
+++ b/libmisc/Makefile
@@ -8,7 +8,7 @@ include $(TOPDIR)/include/builddefs
 LTLIBRARY = libmisc.la
 LTLDFLAGS =
 
-CFILES = quote.c unquote.c high_water_alloc.c next_line.c
+CFILES = quote.c unquote.c high_water_alloc.c next_line.c walk_tree.c
 
 default: $(LTLIBRARY)
 install install-dev install-lib:
diff --git a/libmisc/walk_tree.c b/libmisc/walk_tree.c
new file mode 100644
index 0000000..62bc74d
--- /dev/null
+++ b/libmisc/walk_tree.c
@@ -0,0 +1,100 @@
+/*
+  File: walk_tree.c
+
+  Copyright (C) 2007 Andreas Gruenbacher <a.gruenbacher@computer.org>
+
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Library General Public
+  License as published by the Free Software Foundation; either
+  version 2 of the License, 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
+  Library General Public License for more details.
+
+  You should have received a copy of the GNU Library General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+#include "walk_tree.h"
+
+static int walk_tree_rec(const char *path, int walk_flags,
+			 int (*func)(const char *, const struct stat *, int, void *),
+			 void *arg, int depth)
+{
+	int (*xstat)(const char *, struct stat *) = lstat;
+	struct stat st;
+	int local_walk_flags = walk_flags, err;
+
+	/* Default to traversing symlinks on the command line, traverse all symlinks
+	 * with -L, and do not traverse symlinks with -P. (This is similar to chown.)
+	 */
+
+follow_symlink:
+	if (xstat(path, &st) != 0)
+		return func(path, NULL, local_walk_flags | WALK_TREE_FAILED, arg);
+	if (S_ISLNK(st.st_mode)) {
+		if ((local_walk_flags & WALK_TREE_PHYSICAL) ||
+		    (!(local_walk_flags & WALK_TREE_LOGICAL) && depth > 1))
+			return 0;
+		local_walk_flags |= WALK_TREE_SYMLINK;
+		xstat = stat;
+		if (local_walk_flags & WALK_TREE_DEREFERENCE)
+			goto follow_symlink;
+	}
+	err = func(path, &st, local_walk_flags, arg);
+	if ((local_walk_flags & WALK_TREE_RECURSIVE) &&
+	    (S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode))) {
+		char path2[FILENAME_MAX];
+		DIR *dir;
+		struct dirent *entry;
+		int err2;
+
+		dir = opendir(path);
+		if (!dir) {
+			/* PATH may be a symlink to a regular file or a dead symlink
+			 * which we didn't follow above.
+			 */
+			if (errno != ENOTDIR && errno != ENOENT)
+				err += func(path, &st,
+					    local_walk_flags | WALK_TREE_FAILED, arg);
+			return err;
+		}
+		while ((entry = readdir(dir)) != NULL) {
+			if (!strcmp(entry->d_name, ".") || !strcmp(entry->d_name, ".."))
+				continue;
+			err2 = snprintf(path2, sizeof(path2), "%s/%s", path,
+				       entry->d_name);
+			if (err2 < 0 || err2 > FILENAME_MAX) {
+				errno = ENAMETOOLONG;
+				err += func(path, NULL,
+					    local_walk_flags | WALK_TREE_FAILED, arg);
+				continue;
+			}
+			err += walk_tree_rec(path2, walk_flags, func, arg, depth + 1);
+		}
+		if (closedir(dir) != 0)
+			err += func(path, &st, local_walk_flags | WALK_TREE_FAILED, arg);
+	}
+	return err;
+}
+
+int walk_tree(const char *path, int walk_flags,
+	      int (*func)(const char *, const struct stat *, int, void *), void *arg)
+{
+	if (strlen(path) >= FILENAME_MAX) {
+		errno = ENAMETOOLONG;
+		return func(path, NULL, WALK_TREE_FAILED, arg);
+	}
+	return walk_tree_rec(path, walk_flags, func, arg, 1);
+}
diff --git a/setfacl/Makefile b/setfacl/Makefile
index b036c63..9cedf38 100644
--- a/setfacl/Makefile
+++ b/setfacl/Makefile
@@ -9,8 +9,8 @@ LTCOMMAND = setfacl
 CFILES = setfacl.c do_set.c sequence.c parse.c
 HFILES = sequence.h parse.h
 
-LLDLIBS = $(LIBACL) $(LIBATTR) $(LIBMISC)
-LTDEPENDENCIES = $(LIBACL) $(LIBMISC)
+LLDLIBS = $(LIBMISC) $(LIBACL) $(LIBATTR)
+LTDEPENDENCIES = $(LIBMISC) $(LIBACL)
 
 default: $(LTCOMMAND)
 
diff --git a/setfacl/do_set.c b/setfacl/do_set.c
index cca1d56..a4fc760 100644
--- a/setfacl/do_set.c
+++ b/setfacl/do_set.c
@@ -36,10 +36,10 @@
 #include "sequence.h"
 #include "parse.h"
 #include "config.h"
+#include "walk_tree.h"
 
 
 extern const char *progname;
-extern int opt_recursive;
 extern int opt_recalculate;
 extern int opt_test;
 extern int print_options;
@@ -259,8 +259,10 @@ int
 do_set(
 	const char *path_p,
 	const struct stat *st,
-	const seq_t seq)
+	int walk_flags,
+	void *arg)
 {
+	const seq_t seq = (const seq_t)arg;
 	acl_t old_acl = NULL, old_default_acl = NULL;
 	acl_t acl = NULL, default_acl = NULL;
 	acl_t *xacl, *old_xacl;
@@ -272,6 +274,11 @@ do_set(
 	int acl_modified = 0, default_acl_modified = 0;
 	int acl_mask_provided = 0, default_acl_mask_provided = 0;
 
+	if (walk_flags & WALK_TREE_FAILED) {
+		fprintf(stderr, "%s: %s: %s\n", progname, path_p, strerror(errno));
+		return 1;
+	}
+
 	/* Execute the commands in seq (read ACLs on demand) */
 	error = seq_get_cmd(seq, SEQ_FIRST_CMD, &cmd);
 	if (error == 0)
@@ -426,7 +433,7 @@ do_set(
 	}
 
 	/* Only directores can have default ACLs */
-	if (default_acl && !S_ISDIR(st->st_mode) && opt_recursive) {
+	if (default_acl && !S_ISDIR(st->st_mode) && (walk_flags & WALK_TREE_RECURSIVE)) {
 		/* In recursive mode, ignore default ACLs for files */
 		acl_free(default_acl);
 		default_acl = NULL;
diff --git a/setfacl/setfacl.c b/setfacl/setfacl.c
index 1304d04..c9cdec2 100644
--- a/setfacl/setfacl.c
+++ b/setfacl/setfacl.c
@@ -28,20 +28,15 @@
 #include <sys/stat.h>
 #include <dirent.h>
 #include <libgen.h>
-#include <ftw.h>
 #include <getopt.h>
 #include <locale.h>
 #include "config.h"
 #include "sequence.h"
 #include "parse.h"
+#include "walk_tree.h"
 #include "misc.h"
 
-extern int
-do_set(
-        const char *path_p,
-        const struct stat *stat_p,
-	const seq_t seq);
-
+extern int do_set(const char *path_p, const struct stat *stat_p, int flags, void *arg);
 
 #define POSIXLY_CORRECT_STR "POSIXLY_CORRECT"
 
@@ -82,9 +77,7 @@ struct option long_options[] = {
 const char *progname;
 const char *cmd_line_options, *cmd_line_spec;
 
-int opt_recursive;  /* recurse into sub-directories? */
-int opt_walk_logical;  /* always follow symbolic links */
-int opt_walk_physical;  /* never follow symbolic links */
+int walk_flags = WALK_TREE_DEREFERENCE;
 int opt_recalculate;  /* recalculate mask entry (0=default, 1=yes, -1=no) */
 int opt_promote;  /* promote access ACL to default ACL */
 int opt_test;  /* do not write to the file system.
@@ -188,7 +181,7 @@ restore(
 		stat.st_uid = uid;
 		stat.st_gid = gid;
 
-		error = do_set(path_p, &stat, seq);
+		error = do_set(path_p, &stat, 0, seq);
 		if (error != 0) {
 			status = 1;
 			goto resume;
@@ -275,77 +268,6 @@ void help(void)
 }
 
 
-static int __errors;
-static seq_t __seq;
-
-int __do_set(const char *file, const struct stat *stat,
-             int flag, struct FTW *ftw)
-{
-	int saved_errno = errno;
-	
-	/* Process the target of a symbolic link, and traverse the link,
-	   only if doing a logical walk, or if the symbolic link was
-	   specified on the command line. Always skip symbolic links if
-	   doing a physical walk. */
-
-	if (S_ISLNK(stat->st_mode) &&
-	    (opt_walk_physical || (ftw->level > 0 && !opt_walk_logical)))
-		return 0;
-
-	if (do_set(file, stat, __seq))
-		__errors++;
-
-	if (flag == FTW_DNR && opt_recursive) {
-		/* Item is a directory which can't be read. */
-		fprintf(stderr, "%s: %s: %s\n",
-			progname, file, strerror(saved_errno));
-		return 0;
-	}
-
-	/* We also get here in non-recursive mode. In that case,
-	   return something != 0 to abort nftw. */
-
-	if (!opt_recursive)
-		return 1;
-
-	return 0;
-}
-
-char *resolve_symlinks(const char *file)
-{
-	static char buffer[4096];
-	struct stat stat;
-	char *path = NULL;
-
-	if (lstat(file, &stat) == -1)
-		return path;
-
-	if (S_ISLNK(stat.st_mode) && !opt_walk_physical)
-		path = realpath(file, buffer);
-	else
-		path = (char *)file;    /* not a symlink, use given path */
-
-	return path;
-}
-
-int walk_tree(const char *file, seq_t seq)
-{
-	const char *p;
-
-	__errors = 0;
-	__seq = seq;
-	if ((p = resolve_symlinks(file)) == NULL) {
-		fprintf(stderr, "%s: %s: %s\n", progname,
-			xquote(file), strerror(errno));
-		__errors++;
-	} else if (nftw(p, __do_set, 0, opt_walk_logical ? 0 : FTW_PHYS) < 0) {
-		fprintf(stderr, "%s: %s: %s\n", progname,
-			xquote(file), strerror(errno));
-		__errors++;
-	}
-	return __errors;
-}
-
 int next_file(const char *arg, seq_t seq)
 {
 	char *line;
@@ -353,14 +275,14 @@ int next_file(const char *arg, seq_t seq)
 
 	if (strcmp(arg, "-") == 0) {
 		while ((line = next_line(stdin)))
-			errors = walk_tree(line, seq);
+			errors = walk_tree(line, walk_flags, do_set, seq);
 		if (!feof(stdin)) {
 			fprintf(stderr, _("%s: Standard input: %s\n"),
 				progname, strerror(errno));
 			errors = 1;
 		}
 	} else {
-		errors = walk_tree(arg, seq);
+		errors = walk_tree(arg, walk_flags, do_set, seq);
 	}
 	return errors ? 1 : 0;
 }
@@ -627,17 +549,17 @@ int main(int argc, char *argv[])
 				break;
 
 			case 'R':  /* recursive */
-				opt_recursive = 1;
+				walk_flags |= WALK_TREE_RECURSIVE;
 				break;
 
 			case 'L':  /* follow symlinks */
-				opt_walk_logical = 1;
-				opt_walk_physical = 0;
+				walk_flags |= WALK_TREE_LOGICAL;
+				walk_flags &= ~WALK_TREE_PHYSICAL;
 				break;
 
 			case 'P':  /* do not follow symlinks */
-				opt_walk_logical = 0;
-				opt_walk_physical = 1;
+				walk_flags |= WALK_TREE_PHYSICAL;
+				walk_flags &= ~WALK_TREE_LOGICAL;
 				break;
 
 			case 't':  /* test mode */