Return to attr_copy_fd.c CVS log

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New attr userspace package - transition to the trusted namespace for XFS,
Add in the new attribute copying routines from Andreas, and also update
the license info in the syscall man pages so that other folks can use em
too.
Library routine for copying extended attributes between files.

/* Copy extended attributes between files. */
 
/* Copyright (C) 2002 Andreas Gruenbacher <agruen@suse.de>, SuSE Linux AG.

   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 2, 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; see the file COPYING.  If not, write to the Free
   Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */

#if defined (HAVE_CONFIG_H)
#include "config.h"
#endif

#include <sys/types.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#if defined(HAVE_ALLOCA_H)
# include <alloca.h>
#endif

#if defined(HAVE_ATTR_XATTR_H)
# include <attr/xattr.h>
#endif

#define ERROR_CONTEXT_MACROS
#include "error_context.h"

#if !defined(ENOTSUP)
# define ENOTSUP (-1)
#endif

#if defined(HAVE_ALLOCA)
# define my_alloc(size) alloca (size)
# define my_free(ptr) do { } while(0)
#else
# define my_alloc(size) malloc (size)
# define my_free(ptr) free (ptr)
#endif

static int
check_no_acl(const char *name, struct error_context *ctx)
{
	return strcmp(name, "system.posix_acl_access") &&
	       strcmp(name, "system.posix_acl_default");
}

/* Copy extended attributes from src_path to dst_path. If the file
   has an extended Access ACL (system.posix_acl_access) and that is
   copied successfully, the file mode permission bits are copied as
   a side effect. This may not always the case, so the file mode
   and/or ownership must be copied separately. */
int
attr_copy_fd(const char *src_path, int src_fd,
	     const char *dst_path, int dst_fd,
	     int (*check) (const char *, struct error_context *),
	     struct error_context *ctx)
{
#if defined(HAVE_FLISTXATTR) && defined(HAVE_FGETXATTR) && \
    defined(HAVE_FSETXATTR)
	int ret = 0;
	ssize_t size;
	char *names = NULL, *end_names, *name, *value = NULL;

	/* ignore acls by default */
	if (check == NULL)
		check = check_no_acl;

	size = flistxattr (src_fd, NULL, 0);
	if (size < 0) {
		if (errno != ENOSYS && errno != ENOTSUP) {
			const char *qpath = quote (ctx, src_path);
			error (ctx, _("listing attributes of %s"), qpath);
			quote_free (ctx, qpath);
			ret = -1;
		}
		goto getout;
	}
	names = (char *) my_alloc (size+1);
	if (names == NULL) {
		error (ctx, "");
		ret = -1;
		goto getout;
	}
	size = flistxattr (src_fd, names, size);
	if (size < 0) {
		const char *qpath = quote (ctx, src_path);
		error (ctx, _("listing attributes of %s"), qpath);
		quote_free (ctx, qpath);
		my_free (names);
		ret = -1;
		goto getout;
	} else {
		names[size] = '\0';
		end_names = names + size;
	}

	for (name = names; name != end_names; name = strchr(name, '\0') + 1) {
		void *old_value;

		/* check if this attribute shall be preserved */
		if (!*name || !check(name, ctx))
			continue;

		size = fgetxattr (src_fd, name, NULL, 0);
		if (size < 0) {
			const char *qpath = quote (ctx, src_path);
			const char *qname = quote (ctx, name);
			error (ctx, _("getting attribute %s of %s"),
			       qpath, qname);
			quote_free (ctx, qname);
			quote_free (ctx, qpath);
			ret = -1;
			continue;  /* may not have permission to access */
		}
		value = (char *) realloc (old_value = value, size);
		if (size != 0 && value == NULL) {
			free(old_value);
			error (ctx, "");
			ret = -1;
		}
		size = fgetxattr (src_fd, name, value, size);
		if (size < 0) {
			const char *qpath = quote (ctx, src_path);
			const char *qname = quote (ctx, name);
			error (ctx, _("getting attribute %s of %s"),
			       qname, qpath);
			quote_free (ctx, qname);
			quote_free (ctx, qpath);
			ret = -1;
		}
		if (fsetxattr (dst_fd, name, value, size, 0) != 0)
		{
			const char *qpath = quote (ctx, dst_path);
			if (errno == ENOSYS) {
				error (ctx, _("setting attributes for %s"),
				       qpath);
				ret = -1;
				break;  /* no hope of getting any further */
			} else {
				const char *qname = quote (ctx, name);
				error (ctx, _("setting attribute %s for %s"),
				       qname, qpath);
				quote_free (ctx, qname);
				ret = -1;
			}
			quote_free (ctx, qpath);
		}
	}
getout:
	free (value);
	my_free (names);
	return ret;
#else
	return 0;
#endif
}