extmod/modwebsocket: Start module for WebSocket helper functions.

Currently, only write support is implemented (of limited buffer size).

extmod/modwebsocket.c

+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Paul Sokolovsky
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+
+#include "py/nlr.h"
+#include "py/obj.h"
+#include "py/stream.h"
+
+#if MICROPY_PY_WEBSOCKET
+
+enum { FRAME_HEADER, FRAME_OPT, PAYLOAD };
+
+typedef struct _mp_obj_websocket_t {
+    mp_obj_base_t base;
+    mp_obj_t sock;
+    uint32_t mask;
+    byte state;
+    byte to_recv;
+    byte mask_pos;
+    byte buf[4];
+} mp_obj_websocket_t;
+
+STATIC mp_obj_t websocket_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+    assert(n_args == 1);
+    mp_obj_websocket_t *o = m_new_obj(mp_obj_websocket_t);
+    o->base.type = type;
+    o->sock = args[0];
+    o->state = FRAME_HEADER;
+    o->to_recv = 2;
+    o->mask_pos = 0;
+    return o;
+}
+
+STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void *buf, mp_uint_t size, int *errcode) {
+    mp_obj_websocket_t *self = self_in;
+    assert(size < 126);
+    byte header[] = {0x81, size};
+
+    mp_uint_t out_sz = mp_stream_writeall(self->sock, header, sizeof(header), errcode);
+    if (out_sz == MP_STREAM_ERROR) {
+        return MP_STREAM_ERROR;
+    }
+    return mp_stream_writeall(self->sock, buf, size, errcode);
+}
+
+STATIC const mp_map_elem_t websocket_locals_dict_table[] = {
+    { MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&mp_stream_write_obj },
+};
+STATIC MP_DEFINE_CONST_DICT(websocket_locals_dict, websocket_locals_dict_table);
+
+STATIC const mp_stream_p_t websocket_stream_p = {
+//    .read = websocket_read,
+    .write = websocket_write,
+};
+
+STATIC const mp_obj_type_t websocket_type = {
+    { &mp_type_type },
+    .name = MP_QSTR_websocket,
+    .make_new = websocket_make_new,
+    .stream_p = &websocket_stream_p,
+    .locals_dict = (mp_obj_t)&websocket_locals_dict,
+};
+
+STATIC const mp_map_elem_t websocket_module_globals_table[] = {
+    { MP_OBJ_NEW_QSTR(MP_QSTR___name__), MP_OBJ_NEW_QSTR(MP_QSTR_websocket) },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_websocket), (mp_obj_t)&websocket_type },
+};
+
+STATIC MP_DEFINE_CONST_DICT(websocket_module_globals, websocket_module_globals_table);
+
+const mp_obj_module_t mp_module_websocket = {
+    .base = { &mp_type_module },
+    .name = MP_QSTR_websocket,
+    .globals = (mp_obj_dict_t*)&websocket_module_globals,
+};
+
+#endif // MICROPY_PY_WEBSOCKET

py/builtin.h

@@ -105,6 +105,7 @@ extern const mp_obj_module_t mp_module_urandom;
 extern const mp_obj_module_t mp_module_ussl;
 extern const mp_obj_module_t mp_module_machine;
 extern const mp_obj_module_t mp_module_lwip;
+extern const mp_obj_module_t mp_module_websocket;
 
 // extmod functions
 MP_DECLARE_CONST_FUN_OBJ(pyb_mount_obj);

py/mpconfig.h

@@ -836,6 +836,10 @@ typedef double mp_float_t;
 #define MICROPY_PY_USSL (0)
 #endif
 
+#ifndef MICROPY_PY_WEBSOCKET
+#define MICROPY_PY_WEBSOCKET (0)
+#endif
+
 /*****************************************************************************/
 /* Hooks for a port to add builtins                                          */
 

py/objmodule.c

@@ -193,6 +193,9 @@ STATIC const mp_rom_map_elem_t mp_builtin_module_table[] = {
 #if MICROPY_PY_LWIP
     { MP_ROM_QSTR(MP_QSTR_lwip), MP_ROM_PTR(&mp_module_lwip) },
 #endif
+#if MICROPY_PY_WEBSOCKET
+    { MP_ROM_QSTR(MP_QSTR_websocket), MP_ROM_PTR(&mp_module_websocket) },
+#endif
 
     // extra builtin modules as defined by a port
     MICROPY_PORT_BUILTIN_MODULES

py/py.mk

@@ -169,6 +169,7 @@ PY_O_BASENAME = \
 	../extmod/machine_mem.o \
 	../extmod/modussl.o \
 	../extmod/modurandom.o \
+	../extmod/modwebsocket.o \
 	../extmod/fsusermount.o \
 	../extmod/vfs_fat.o \
 	../extmod/vfs_fat_ffconf.o \

py/qstrdefs.h

@@ -752,3 +752,7 @@ Q(uniform)
 Q(VfsFat)
 Q(flush)
 #endif
+
+#if MICROPY_PY_WEBSOCKET
+Q(websocket)
+#endif