diff options
Diffstat (limited to 'hurd/xattr.c')
| -rw-r--r-- | hurd/xattr.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/hurd/xattr.c b/hurd/xattr.c new file mode 100644 index 0000000..cf3e22d --- /dev/null +++ b/hurd/xattr.c @@ -0,0 +1,201 @@ +/* Support for *xattr interfaces on GNU/Hurd. + Copyright (C) 2006 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <hurd.h> +#include <hurd/xattr.h> +#include <string.h> +#include <sys/mman.h> + +/* Right now we support only a fixed set of xattr names for Hurd features. + There are no RPC interfaces for free-form xattr names and values. + + Name Value encoding + ---- ----- -------- + gnu.author empty if st_author==st_uid + uid_t giving st_author value + gnu.translator empty if no passive translator + translator and arguments: "/hurd/foo\0arg1\0arg2\0" +*/ + +error_t +_hurd_xattr_get (io_t port, const char *name, void *value, size_t *size) +{ + if (strncmp (name, "gnu.", 4)) + return EOPNOTSUPP; + name += 4; + + if (!strcmp (name, "author")) + { + struct stat64 st; + error_t err = __io_stat (port, &st); + if (err) + return err; + if (st.st_author == st.st_uid) + *size = 0; + else if (value) + { + if (*size < sizeof st.st_author) + return ERANGE; + memcpy (value, &st.st_author, sizeof st.st_author); + } + *size = sizeof st.st_author; + return 0; + } + + if (!strcmp (name, "translator")) + { + char *buf = value; + size_t bufsz = value ? *size : 0; + error_t err = __file_get_translator (port, &buf, &bufsz); + if (err) + return err; + if (value != NULL && *size < bufsz) + { + if (buf != value) + munmap (buf, bufsz); + return -ERANGE; + } + if (buf != value && bufsz > 0) + { + if (value != NULL) + memcpy (value, buf, bufsz); + munmap (buf, bufsz); + } + *size = bufsz; + return 0; + } + + return EOPNOTSUPP; +} + +error_t +_hurd_xattr_set (io_t port, const char *name, const void *value, size_t size, + int flags) +{ + if (strncmp (name, "gnu.", 4)) + return EOPNOTSUPP; + name += 4; + + if (!strcmp (name, "author")) + switch (size) + { + default: + return EINVAL; + case 0: /* "Clear" author by setting to st_uid. */ + { + struct stat64 st; + error_t err = __io_stat (port, &st); + if (err) + return err; + if (st.st_author == st.st_uid) + { + /* Nothing to do. */ + if (flags & XATTR_REPLACE) + return ENODATA; + return 0; + } + if (flags & XATTR_CREATE) + return EEXIST; + return __file_chauthor (port, st.st_uid); + } + case sizeof (uid_t): /* Set the author. */ + { + uid_t id; + memcpy (&id, value, sizeof id); + if (flags & (XATTR_CREATE|XATTR_REPLACE)) + { + struct stat64 st; + error_t err = __io_stat (port, &st); + if (err) + return err; + if (st.st_author == st.st_uid) + { + if (flags & XATTR_REPLACE) + return ENODATA; + } + else if (flags & XATTR_CREATE) + return EEXIST; + if (st.st_author == id) + /* Nothing to do. */ + return 0; + } + return __file_chauthor (port, id); + } + } + + if (!strcmp (name, "translator")) + { + if (flags & XATTR_REPLACE) + { + /* Must make sure it's already there. */ + char *buf = NULL; + size_t bufsz = 0; + error_t err = __file_get_translator (port, &buf, &bufsz); + if (err) + return err; + if (bufsz > 0) + { + munmap (buf, bufsz); + return ENODATA; + } + } + return __file_set_translator (port, + FS_TRANS_SET | ((flags & XATTR_CREATE) + ? FS_TRANS_EXCL : 0), 0, 0, + value, size, + MACH_PORT_NULL, MACH_MSG_TYPE_COPY_SEND); + } + + return EOPNOTSUPP; +} + +error_t +_hurd_xattr_remove (io_t port, const char *name) +{ + return _hurd_xattr_set (port, name, NULL, 0, XATTR_REPLACE); +} + +error_t +_hurd_xattr_list (io_t port, void *buffer, size_t *size) +{ + size_t total = 0; + char *bufp = buffer; + inline void add (const char *name, size_t len) + { + total += len; + if (bufp != NULL && total <= *size) + bufp = __mempcpy (bufp, name, len); + } +#define add(s) add (s, sizeof s) + + struct stat64 st; + error_t err = __io_stat (port, &st); + if (err) + return err; + + if (st.st_author != st.st_uid) + add ("gnu.author"); + if (st.st_mode & S_IPTRANS) + add ("gnu.translator"); + + if (buffer != NULL && total > *size) + return ERANGE; + *size = total; + return 0; +} |