[PATCH glibc] Add file record locking support
Hi,
Attached is the patch adding support for file record locking in glibc,
as implemented in Hurd by Neal Walfield and others. This patch should be
applied after the corresponding hurd patch series in case glibc and hurd
are not built simultaneously. (Maybe the conversion functions as written
by Samuel should be used to verify struct sizes:
http://lists.gnu.org/archive/html/bug-hurd/2014-08/msg00082.html)
Thanks!
sysdeps/mach/hurd/Changelog
2014-08-21 Svante Signell <svante.signell@gmail.com>
* fcntl.c: Add support for file-record-lock RPC fixing posix
file locking using the flock64 version of struct flock.
* bits/fcntl.h: Since MIG cannot mix 32 bit and 64 bit
integers define unique numbers for F_GETLK64, F_SETLK64 and
F_SETLKW64 to prepare for a flock64 implementation of file
record locking in hurd.
Index: glibc-2.19/sysdeps/mach/hurd/bits/fcntl.h
===================================================================
--- glibc-2.19.orig/sysdeps/mach/hurd/bits/fcntl.h
+++ glibc-2.19/sysdeps/mach/hurd/bits/fcntl.h
@@ -163,9 +163,18 @@
# define F_GETOWN 5 /* Get owner (receiver of SIGIO). */
# define F_SETOWN 6 /* Set owner (receiver of SIGIO). */
#endif
+#ifdef __USE_FILE_OFFSET64
+# define F_GETLK F_GETLK64
+# define F_SETLK F_SETLK64
+# define F_SETLKW F_SETLKW64
+#else
#define F_GETLK 7 /* Get record locking info. */
#define F_SETLK 8 /* Set record locking info (non-blocking). */
#define F_SETLKW 9 /* Set record locking info (blocking). */
+#endif
+#define F_GETLK64 10 /* Get record locking info. */
+#define F_SETLK64 11 /* Set record locking info (non-blocking). */
+#define F_SETLKW64 12 /* Set record locking info (blocking). */
#ifdef __USE_XOPEN2K8
# define F_DUPFD_CLOEXEC 1030 /* Duplicate, set FD_CLOEXEC on new one. */
Index: glibc-2.19/sysdeps/mach/hurd/fcntl.c
===================================================================
--- glibc-2.19.orig/sysdeps/mach/hurd/fcntl.c
+++ glibc-2.19/sysdeps/mach/hurd/fcntl.c
@@ -20,7 +20,6 @@
#include <hurd.h>
#include <hurd/fd.h>
#include <stdarg.h>
-#include <sys/file.h> /* XXX for LOCK_* */
/* Perform file control operations on FD. */
int
@@ -128,56 +127,87 @@ __libc_fcntl (int fd, int cmd, ...)
case F_SETLK:
case F_SETLKW:
{
- /* XXX
- We need new RPCs to support POSIX.1 fcntl file locking!!
- For the time being we support the whole-file case only,
- with all kinds of WRONG WRONG WRONG semantics,
- by using flock. This is definitely the Wrong Thing,
- but it might be better than nothing (?). */
struct flock *fl = va_arg (ap, struct flock *);
- va_end (ap);
- switch (cmd)
- {
- case F_GETLK:
- errno = ENOSYS;
- return -1;
- case F_SETLK:
- cmd = LOCK_NB;
- break;
- default:
- cmd = 0;
+ struct flock64 *fl64 = malloc (sizeof (struct flock64));
+
+ if (cmd == F_GETLK)
+ cmd = F_GETLK64;
+ if (cmd == F_SETLK)
+ cmd = F_SETLK64;
+ if (cmd == F_SETLKW)
+ cmd = F_SETLKW64;
+
+ switch (fl->l_type)
+ {
+ case F_RDLCK:
+ case F_WRLCK:
+ case F_UNLCK:
break;
- }
- switch (fl->l_type)
- {
- case F_RDLCK: cmd |= LOCK_SH | __LOCK_ATOMIC; break;
- case F_WRLCK: cmd |= LOCK_EX | __LOCK_ATOMIC; break;
- case F_UNLCK: cmd |= LOCK_UN; break;
default:
errno = EINVAL;
return -1;
+ break;
}
- switch (fl->l_whence)
- {
- case SEEK_SET:
- if (fl->l_start == 0 && fl->l_len == 0) /* Whole file request. */
- break;
- /* It seems to be common for applications to lock the first
- byte of the file when they are really doing whole-file locking.
- So, since it's so wrong already, might as well do that too. */
- if (fl->l_start == 0 && fl->l_len == 1)
- break;
- /* FALLTHROUGH */
- case SEEK_CUR:
- case SEEK_END:
- errno = ENOTSUP;
- return -1;
+ switch (fl->l_whence)
+ {
+ case SEEK_SET:
+ case SEEK_CUR:
+ case SEEK_END:
+ break;
+ default:
+ errno = EINVAL;
+ return -1;
+ break;
+ }
+
+ fl64->l_type = fl->l_type;
+ fl64->l_whence = fl->l_whence;
+ fl64->l_start = fl->l_start;
+ fl64->l_len = fl->l_len;
+ fl64->l_pid = fl->l_pid;
+ err = HURD_FD_PORT_USE (d, __file_record_lock (port, cmd, fl64));
+ fl->l_type = fl64->l_type;
+ fl->l_whence = fl64->l_whence;
+ fl->l_start = fl64->l_start;
+ fl->l_len = fl64->l_len;
+ fl->l_pid = fl64->l_pid;
+ free (fl64);
+ result = err ? __hurd_dfail (fd, err) : 0;
+ break;
+ }
+
+ case F_GETLK64:
+ case F_SETLK64:
+ case F_SETLKW64:
+ {
+ struct flock64 *fl = va_arg (ap, struct flock64 *);
+
+ switch (fl->l_type)
+ {
+ case F_RDLCK:
+ case F_WRLCK:
+ case F_UNLCK:
+ break;
default:
errno = EINVAL;
return -1;
+ break;
+ }
+ switch (fl->l_whence)
+ {
+ case SEEK_SET:
+ case SEEK_CUR:
+ case SEEK_END:
+ break;
+ default:
+ errno = EINVAL;
+ return -1;
+ break;
}
- return __flock (fd, cmd);
+ err = HURD_FD_PORT_USE (d, __file_record_lock (port, cmd, fl));
+ result = err ? __hurd_dfail (fd, err) : 0;
+ break;
}
case F_GETFL: /* Get per-open flags. */
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