sync

contrib/python_1.5.2-fcntl_lockf.diff

+--- python-1.5.2/Modules/fcntlmodule.c.orig	Wed Jan  6 13:44:23 1999
++++ python-1.5.2/Modules/fcntlmodule.c	Sun Apr  1 07:42:54 2001
+@@ -233,30 +233,12 @@
+ {
+ 	int fd, code, ret, whence = 0;
+ 	PyObject *lenobj = NULL, *startobj = NULL;
++       struct flock l;
+ 
+ 	if (!PyArg_ParseTuple(args, "ii|OOi", &fd, &code,
+ 			      &lenobj, &startobj, &whence))
+ 	    return NULL;
+ 
+-#ifndef LOCK_SH
+-#define LOCK_SH		1	/* shared lock */
+-#define LOCK_EX		2	/* exclusive lock */
+-#define LOCK_NB		4	/* don't block when locking */
+-#define LOCK_UN		8	/* unlock */
+-#endif
+-	{
+-		struct flock l;
+-		if (code == LOCK_UN)
+-			l.l_type = F_UNLCK;
+-		else if (code & LOCK_SH)
+-			l.l_type = F_RDLCK;
+-		else if (code & LOCK_EX)
+-			l.l_type = F_WRLCK;
+-		else {
+-			PyErr_SetString(PyExc_ValueError,
+-					"unrecognized flock argument");
+-			return NULL;
+-		}
+ 		l.l_start = l.l_len = 0;
+ 		if (startobj != NULL) {
+ #if !defined(HAVE_LARGEFILE_SUPPORT)
+@@ -281,10 +263,45 @@
+ 				return NULL;
+ 		}
+ 		l.l_whence = whence;
++       switch (code)
++         {
++         case F_TEST:
++           /* Test the lock: return 0 if FD is unlocked or locked by this process;
++              return -1, set errno to EACCES, if another process holds the lock.  */
++           if (fcntl (fd, F_GETLK, &l) < 0) {
++             PyErr_SetFromErrno(PyExc_IOError);
++             return NULL;
++           }
++           if (l.l_type == F_UNLCK || l.l_pid == getpid ()) {
++             Py_INCREF(Py_None);
++             return Py_None;
++           }
++           errno = EACCES;
++           PyErr_SetFromErrno(PyExc_IOError);
++           return NULL;
++
++         case F_ULOCK:
++           l.l_type = F_UNLCK;
++           code = F_SETLK;
++           break;
++         case F_LOCK:
++           l.l_type = F_WRLCK;
++           code = F_SETLKW;
++           break;
++         case F_TLOCK:
++           l.l_type = F_WRLCK;
++           code = F_SETLK;
++           break;
++
++         default:
++           PyErr_SetString(PyExc_ValueError,
++                           "unrecognized flock argument");
++           return NULL;
++         }
+ 		Py_BEGIN_ALLOW_THREADS
+-		ret = fcntl(fd, (code & LOCK_NB) ? F_SETLK : F_SETLKW, &l);
++         ret = fcntl(fd, code, &l);
+ 		Py_END_ALLOW_THREADS
+-	}
++
+ 	if (ret < 0) {
+ 		PyErr_SetFromErrno(PyExc_IOError);
+ 		return NULL;