track embedded python distribution

1 files changed, 223 insertions, 0 deletions

diff --git a/python/gevent/libev/libev_vfd.h b/python/gevent/libev/libev_vfd.h
new file mode 100644
index 0000000..ec16a28
--- /dev/null
+++ b/python/gevent/libev/libev_vfd.h
@@ -0,0 +1,223 @@
+#ifdef _WIN32
+#ifdef _WIN64
+typedef PY_LONG_LONG vfd_socket_t;
+#define vfd_socket_object PyLong_FromLongLong
+#else
+typedef long vfd_socket_t;
+#define vfd_socket_object PyInt_FromLong
+#endif
+#ifdef LIBEV_EMBED
+/*
+ * If libev on win32 is embedded, then we can use an
+ * arbitrary mapping between integer fds and OS
+ * handles. Then by defining special macros libev
+ * will use our functions.
+ */
+
+#define WIN32_LEAN_AND_MEAN
+#include <winsock2.h>
+#include <windows.h>
+
+typedef struct vfd_entry_t
+{
+	vfd_socket_t handle; /* OS handle, i.e. SOCKET */
+	int count; /* Reference count, 0 if free */
+	int next; /* Next free fd, -1 if last */
+} vfd_entry;
+
+#define VFD_INCREMENT 128
+static int vfd_num = 0; /* num allocated fds */
+static int vfd_max = 0; /* max allocated fds */
+static int vfd_next = -1; /* next free fd for reuse */
+static PyObject* vfd_map = NULL; /* map OS handle -> virtual fd */
+static vfd_entry* vfd_entries = NULL; /* list of virtual fd entries */
+
+#ifdef WITH_THREAD
+static CRITICAL_SECTION* volatile vfd_lock = NULL;
+static CRITICAL_SECTION* vfd_make_lock()
+{
+	if (vfd_lock == NULL) {
+		/* must use malloc and not PyMem_Malloc here */
+		CRITICAL_SECTION* lock = malloc(sizeof(CRITICAL_SECTION));
+		InitializeCriticalSection(lock);
+		if (InterlockedCompareExchangePointer(&vfd_lock, lock, NULL) != NULL) {
+			/* another thread initialized lock first */
+			DeleteCriticalSection(lock);
+			free(lock);
+		}
+	}
+	return vfd_lock;
+}
+#define VFD_LOCK_ENTER  EnterCriticalSection(vfd_make_lock())
+#define VFD_LOCK_LEAVE  LeaveCriticalSection(vfd_lock)
+#define VFD_GIL_DECLARE PyGILState_STATE ___save
+#define VFD_GIL_ENSURE  ___save = PyGILState_Ensure()
+#define VFD_GIL_RELEASE PyGILState_Release(___save)
+#else
+#define VFD_LOCK_ENTER
+#define VFD_LOCK_LEAVE
+#define VFD_GIL_DECLARE
+#define VFD_GIL_ENSURE
+#define VFD_GIL_RELEASE
+#endif
+
+/*
+ * Given a virtual fd returns an OS handle or -1
+ * This function is speed critical, so it cannot use GIL
+ */
+static vfd_socket_t vfd_get(int fd)
+{
+	int handle = -1;
+	VFD_LOCK_ENTER;
+	if (vfd_entries != NULL && fd >= 0 && fd < vfd_num)
+		handle = vfd_entries[fd].handle;
+	VFD_LOCK_LEAVE;
+	return handle;
+}
+
+#define EV_FD_TO_WIN32_HANDLE(fd) vfd_get((fd))
+
+/*
+ * Given an OS handle finds or allocates a virtual fd
+ * Returns -1 on failure and sets Python exception if pyexc is non-zero
+ */
+static int vfd_open_(vfd_socket_t handle, int pyexc)
+{
+	VFD_GIL_DECLARE;
+	int fd = -1;
+	unsigned long arg;
+	PyObject* key = NULL;
+	PyObject* value;
+
+	if (!pyexc) {
+		VFD_GIL_ENSURE;
+	}
+	if (ioctlsocket(handle, FIONREAD, &arg) != 0) {
+		if (pyexc)
+			PyErr_Format(PyExc_IOError,
+#ifdef _WIN64
+				"%lld is not a socket (files are not supported)",
+#else
+				"%ld is not a socket (files are not supported)",
+#endif
+				handle);
+		goto done;
+	}
+	if (vfd_map == NULL) {
+		vfd_map = PyDict_New();
+		if (vfd_map == NULL)
+			goto done;
+	}
+	key = vfd_socket_object(handle);
+	/* check if it's already in the dict */
+	value = PyDict_GetItem(vfd_map, key);
+	if (value != NULL) {
+		/* is it safe to use PyInt_AS_LONG(value) here? */
+		fd = PyInt_AsLong(value);
+		if (fd >= 0) {
+			++vfd_entries[fd].count;
+			goto done;
+		}
+	}
+	/* use the free entry, if available */
+	if (vfd_next >= 0) {
+		fd = vfd_next;
+		vfd_next = vfd_entries[fd].next;
+		VFD_LOCK_ENTER;
+		goto allocated;
+	}
+	/* check if it would be out of bounds */
+	if (vfd_num >= FD_SETSIZE) {
+		/* libev's select doesn't support more that FD_SETSIZE fds */
+		if (pyexc)
+			PyErr_Format(PyExc_IOError, "cannot watch more than %d sockets", (int)FD_SETSIZE);
+		goto done;
+	}
+	/* allocate more space if needed */
+	VFD_LOCK_ENTER;
+	if (vfd_num >= vfd_max) {
+		int newsize = vfd_max + VFD_INCREMENT;
+		vfd_entry* entries = PyMem_Realloc(vfd_entries, sizeof(vfd_entry) * newsize);
+		if (entries == NULL) {
+			VFD_LOCK_LEAVE;
+			if (pyexc)
+				PyErr_NoMemory();
+			goto done;
+		}
+		vfd_entries = entries;
+		vfd_max = newsize;
+	}
+	fd = vfd_num++;
+allocated:
+	/* vfd_lock must be acquired when entering here */
+	vfd_entries[fd].handle = handle;
+	vfd_entries[fd].count = 1;
+	VFD_LOCK_LEAVE;
+	value = PyInt_FromLong(fd);
+	PyDict_SetItem(vfd_map, key, value);
+	Py_DECREF(value);
+done:
+	Py_XDECREF(key);
+	if (!pyexc) {
+		VFD_GIL_RELEASE;
+	}
+	return fd;
+}
+
+#define vfd_open(fd) vfd_open_((fd), 1)
+#define EV_WIN32_HANDLE_TO_FD(handle) vfd_open_((handle), 0)
+
+static void vfd_free_(int fd, int needclose)
+{
+	VFD_GIL_DECLARE;
+	PyObject* key;
+
+	if (needclose) {
+		VFD_GIL_ENSURE;
+	}
+	if (fd < 0 || fd >= vfd_num)
+		goto done; /* out of bounds */
+	if (vfd_entries[fd].count <= 0)
+		goto done; /* free entry, ignore */
+	if (!--vfd_entries[fd].count) {
+		/* fd has just been freed */
+		vfd_socket_t handle = vfd_entries[fd].handle;
+		vfd_entries[fd].handle = -1;
+		vfd_entries[fd].next = vfd_next;
+		vfd_next = fd;
+		if (needclose)
+			closesocket(handle);
+		/* vfd_map is assumed to be != NULL */
+		key = vfd_socket_object(handle);
+		PyDict_DelItem(vfd_map, key);
+		Py_DECREF(key);
+	}
+done:
+	if (needclose) {
+		VFD_GIL_RELEASE;
+	}
+}
+
+#define vfd_free(fd) vfd_free_((fd), 0)
+#define EV_WIN32_CLOSE_FD(fd) vfd_free_((fd), 1)
+
+#else
+/*
+ * If libev on win32 is not embedded in gevent, then
+ * the only way to map vfds is to use the default of
+ * using runtime fds in libev. Note that it will leak
+ * fds, because there's no way of closing them safely
+ */
+#define vfd_get(fd) _get_osfhandle((fd))
+#define vfd_open(fd) _open_osfhandle((fd), 0)
+#define vfd_free(fd)
+#endif
+#else
+/*
+ * On non-win32 platforms vfd_* are noop macros
+ */
+typedef int vfd_socket_t;
+#define vfd_get(fd) (fd)
+#define vfd_open(fd) ((int)(fd))
+#define vfd_free(fd)
+#endif