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modsocket.c

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    Paul Sokolovsky authored
    Its addition was due to an early exploration on how to add CPython-like
    stream interface. It's clear that it's not needed and just takes up
    bytes in all ports.
    59a1201d
    History
    modsocket.c 21.38 KiB
    /*
     * This file is part of the Micro Python project, http://micropython.org/
     *
     * The MIT License (MIT)
     *
     * Copyright (c) 2013, 2014 Damien P. George
     * Copyright (c) 2014 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 <assert.h>
    #include <string.h>
    #include <unistd.h>
    #include <fcntl.h>
    #include <sys/stat.h>
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <netinet/in.h>
    #include <arpa/inet.h>
    #include <netdb.h>
    #include <errno.h>
    
    #include "py/nlr.h"
    #include "py/objtuple.h"
    #include "py/objstr.h"
    #include "py/runtime.h"
    #include "py/stream.h"
    #include "py/builtin.h"
    #include "py/mphal.h"
    
    /*
      The idea of this module is to implement reasonable minimum of
      socket-related functions to write typical clients and servers.
      The module named "usocket" on purpose, to allow to make
      Python-level module more (or fully) compatible with CPython
      "socket", e.g.:
      ---- socket.py ----
      from usocket import *
      from socket_more_funcs import *
      from socket_more_funcs2 import *
      -------------------
      I.e. this module should stay lean, and more functions (if needed)
      should be add to seperate modules (C or Python level).
     */
    
    #define MICROPY_SOCKET_EXTRA (0)
    
    // This type must "inherit" from mp_obj_fdfile_t, i.e. matching subset of
    // fields should have the same layout.
    typedef struct _mp_obj_socket_t {
        mp_obj_base_t base;
        int fd;
    } mp_obj_socket_t;
    
    const mp_obj_type_t mp_type_socket;
    
    // Helper functions
    static inline mp_obj_t mp_obj_from_sockaddr(const struct sockaddr *addr, socklen_t len) {
        return mp_obj_new_bytes((const byte *)addr, len);
    }
    
    STATIC mp_obj_socket_t *socket_new(int fd) {
        mp_obj_socket_t *o = m_new_obj(mp_obj_socket_t);
        o->base.type = &mp_type_socket;
        o->fd = fd;
        return o;
    }
    
    
    STATIC void socket_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
        (void)kind;
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        mp_printf(print, "<_socket %d>", self->fd);
    }
    
    STATIC mp_uint_t socket_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *errcode) {
        mp_obj_socket_t *o = MP_OBJ_TO_PTR(o_in);
        mp_int_t r = read(o->fd, buf, size);
        if (r == -1) {
            *errcode = errno;
            return MP_STREAM_ERROR;
        }
        return r;
    }
    
    STATIC mp_uint_t socket_write(mp_obj_t o_in, const void *buf, mp_uint_t size, int *errcode) {
        mp_obj_socket_t *o = MP_OBJ_TO_PTR(o_in);
        mp_int_t r = write(o->fd, buf, size);
        if (r == -1) {
            *errcode = errno;
            return MP_STREAM_ERROR;
        }
        return r;
    }
    
    STATIC mp_obj_t socket_close(mp_obj_t self_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        // There's a POSIX drama regarding return value of close in general,
        // and EINTR error in particular. See e.g.
        // http://lwn.net/Articles/576478/
        // http://austingroupbugs.net/view.php?id=529
        // The rationale MicroPython follows is that close() just releases
        // file descriptor. If you're interested to catch I/O errors before
        // closing fd, fsync() it.
        close(self->fd);
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_1(socket_close_obj, socket_close);
    
    STATIC mp_obj_t socket_fileno(mp_obj_t self_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        return MP_OBJ_NEW_SMALL_INT(self->fd);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_1(socket_fileno_obj, socket_fileno);
    
    STATIC mp_obj_t socket_connect(mp_obj_t self_in, mp_obj_t addr_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(addr_in, &bufinfo, MP_BUFFER_READ);
        int r = connect(self->fd, (const struct sockaddr *)bufinfo.buf, bufinfo.len);
        RAISE_ERRNO(r, errno);
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_connect_obj, socket_connect);
    
    STATIC mp_obj_t socket_bind(mp_obj_t self_in, mp_obj_t addr_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(addr_in, &bufinfo, MP_BUFFER_READ);
        int r = bind(self->fd, (const struct sockaddr *)bufinfo.buf, bufinfo.len);
        RAISE_ERRNO(r, errno);
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_bind_obj, socket_bind);
    
    STATIC mp_obj_t socket_listen(mp_obj_t self_in, mp_obj_t backlog_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        int r = listen(self->fd, MP_OBJ_SMALL_INT_VALUE(backlog_in));
        RAISE_ERRNO(r, errno);
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_listen_obj, socket_listen);
    
    STATIC mp_obj_t socket_accept(mp_obj_t self_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        // sockaddr_storage isn't stack-friendly (129 bytes or so)
        //struct sockaddr_storage addr;
        byte addr[32];
        socklen_t addr_len = sizeof(addr);
        int fd = accept(self->fd, (struct sockaddr*)&addr, &addr_len);
        RAISE_ERRNO(fd, errno);
    
        mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(2, NULL));
        t->items[0] = MP_OBJ_FROM_PTR(socket_new(fd));
        t->items[1] = mp_obj_new_bytearray(addr_len, &addr);
    
        return MP_OBJ_FROM_PTR(t);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_1(socket_accept_obj, socket_accept);
    
    // Note: besides flag param, this differs from read() in that
    // this does not swallow blocking errors (EAGAIN, EWOULDBLOCK) -
    // these would be thrown as exceptions.
    STATIC mp_obj_t socket_recv(size_t n_args, const mp_obj_t *args) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
        int sz = MP_OBJ_SMALL_INT_VALUE(args[1]);
        int flags = 0;
    
        if (n_args > 2) {
            flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
        }
    
        byte *buf = m_new(byte, sz);
        int out_sz = recv(self->fd, buf, sz, flags);
        RAISE_ERRNO(out_sz, errno);
    
        mp_obj_t ret = mp_obj_new_str_of_type(&mp_type_bytes, buf, out_sz);
        m_del(char, buf, sz);
        return ret;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_recv_obj, 2, 3, socket_recv);
    
    STATIC mp_obj_t socket_recvfrom(size_t n_args, const mp_obj_t *args) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
        int sz = MP_OBJ_SMALL_INT_VALUE(args[1]);
        int flags = 0;
    
        if (n_args > 2) {
            flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
        }
    
        struct sockaddr_storage addr;
        socklen_t addr_len = sizeof(addr);
    
        byte *buf = m_new(byte, sz);
        int out_sz = recvfrom(self->fd, buf, sz, flags, (struct sockaddr*)&addr, &addr_len);
        RAISE_ERRNO(out_sz, errno);
    
        mp_obj_t buf_o = mp_obj_new_str_of_type(&mp_type_bytes, buf, out_sz);
        m_del(char, buf, sz);
    
        mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(2, NULL));
        t->items[0] = buf_o;
        t->items[1] = mp_obj_from_sockaddr((struct sockaddr*)&addr, addr_len);
    
        return MP_OBJ_FROM_PTR(t);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_recvfrom_obj, 2, 3, socket_recvfrom);
    
    // Note: besides flag param, this differs from write() in that
    // this does not swallow blocking errors (EAGAIN, EWOULDBLOCK) -
    // these would be thrown as exceptions.
    STATIC mp_obj_t socket_send(size_t n_args, const mp_obj_t *args) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
        int flags = 0;
    
        if (n_args > 2) {
            flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
        }
    
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_READ);
        int out_sz = send(self->fd, bufinfo.buf, bufinfo.len, flags);
        RAISE_ERRNO(out_sz, errno);
    
        return MP_OBJ_NEW_SMALL_INT(out_sz);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_send_obj, 2, 3, socket_send);
    
    STATIC mp_obj_t socket_sendto(size_t n_args, const mp_obj_t *args) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
        int flags = 0;
    
        mp_obj_t dst_addr = args[2];
        if (n_args > 3) {
            flags = MP_OBJ_SMALL_INT_VALUE(args[2]);
            dst_addr = args[3];
        }
    
        mp_buffer_info_t bufinfo, addr_bi;
        mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_READ);
        mp_get_buffer_raise(dst_addr, &addr_bi, MP_BUFFER_READ);
        int out_sz = sendto(self->fd, bufinfo.buf, bufinfo.len, flags,
                            (struct sockaddr *)addr_bi.buf, addr_bi.len);
        RAISE_ERRNO(out_sz, errno);
    
        return MP_OBJ_NEW_SMALL_INT(out_sz);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_sendto_obj, 3, 4, socket_sendto);
    
    STATIC mp_obj_t socket_setsockopt(size_t n_args, const mp_obj_t *args) {
        (void)n_args; // always 4
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
        int level = MP_OBJ_SMALL_INT_VALUE(args[1]);
        int option = mp_obj_get_int(args[2]);
    
        const void *optval;
        socklen_t optlen;
        int val;
        if (MP_OBJ_IS_INT(args[3])) {
            val = mp_obj_int_get_truncated(args[3]);
            optval = &val;
            optlen = sizeof(val);
        } else {
            mp_buffer_info_t bufinfo;
            mp_get_buffer_raise(args[3], &bufinfo, MP_BUFFER_READ);
            optval = bufinfo.buf;
            optlen = bufinfo.len;
        }
        int r = setsockopt(self->fd, level, option, optval, optlen);
        RAISE_ERRNO(r, errno);
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_setsockopt_obj, 4, 4, socket_setsockopt);
    
    STATIC mp_obj_t socket_setblocking(mp_obj_t self_in, mp_obj_t flag_in) {
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(self_in);
        int val = mp_obj_is_true(flag_in);
        int flags = fcntl(self->fd, F_GETFL, 0);
        RAISE_ERRNO(flags, errno);
        if (val) {
            flags &= ~O_NONBLOCK;
        } else {
            flags |= O_NONBLOCK;
        }
        flags = fcntl(self->fd, F_SETFL, flags);
        RAISE_ERRNO(flags, errno);
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_setblocking_obj, socket_setblocking);
    
    STATIC mp_obj_t socket_makefile(size_t n_args, const mp_obj_t *args) {
        // TODO: CPython explicitly says that closing returned object doesn't close
        // the original socket (Python2 at all says that fd is dup()ed). But we
        // save on the bloat.
        mp_obj_socket_t *self = MP_OBJ_TO_PTR(args[0]);
        mp_obj_t *new_args = alloca(n_args * sizeof(mp_obj_t));
        memcpy(new_args + 1, args + 1, (n_args - 1) * sizeof(mp_obj_t));
        new_args[0] = MP_OBJ_NEW_SMALL_INT(self->fd);
        return mp_builtin_open(n_args, new_args, (mp_map_t*)&mp_const_empty_map);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(socket_makefile_obj, 1, 3, socket_makefile);
    
    STATIC mp_obj_t socket_make_new(const mp_obj_type_t *type_in, size_t n_args, size_t n_kw, const mp_obj_t *args) {
        (void)type_in;
        (void)n_kw;
    
        int family = AF_INET;
        int type = SOCK_STREAM;
        int proto = 0;
    
        if (n_args > 0) {
            assert(MP_OBJ_IS_SMALL_INT(args[0]));
            family = MP_OBJ_SMALL_INT_VALUE(args[0]);
            if (n_args > 1) {
                assert(MP_OBJ_IS_SMALL_INT(args[1]));
                type = MP_OBJ_SMALL_INT_VALUE(args[1]);
                if (n_args > 2) {
                    assert(MP_OBJ_IS_SMALL_INT(args[2]));
                    proto = MP_OBJ_SMALL_INT_VALUE(args[2]);
                }
            }
        }
    
        int fd = socket(family, type, proto);
        RAISE_ERRNO(fd, errno);
        return MP_OBJ_FROM_PTR(socket_new(fd));
    }
    
    STATIC const mp_rom_map_elem_t usocket_locals_dict_table[] = {
        { MP_ROM_QSTR(MP_QSTR_fileno), MP_ROM_PTR(&socket_fileno_obj) },
        { MP_ROM_QSTR(MP_QSTR_makefile), MP_ROM_PTR(&socket_makefile_obj) },
        { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
        { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
        { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
        { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
        { MP_ROM_QSTR(MP_QSTR_connect), MP_ROM_PTR(&socket_connect_obj) },
        { MP_ROM_QSTR(MP_QSTR_bind), MP_ROM_PTR(&socket_bind_obj) },
        { MP_ROM_QSTR(MP_QSTR_listen), MP_ROM_PTR(&socket_listen_obj) },
        { MP_ROM_QSTR(MP_QSTR_accept), MP_ROM_PTR(&socket_accept_obj) },
        { MP_ROM_QSTR(MP_QSTR_recv), MP_ROM_PTR(&socket_recv_obj) },
        { MP_ROM_QSTR(MP_QSTR_recvfrom), MP_ROM_PTR(&socket_recvfrom_obj) },
        { MP_ROM_QSTR(MP_QSTR_send), MP_ROM_PTR(&socket_send_obj) },
        { MP_ROM_QSTR(MP_QSTR_sendto), MP_ROM_PTR(&socket_sendto_obj) },
        { MP_ROM_QSTR(MP_QSTR_setsockopt), MP_ROM_PTR(&socket_setsockopt_obj) },
        { MP_ROM_QSTR(MP_QSTR_setblocking), MP_ROM_PTR(&socket_setblocking_obj) },
        { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&socket_close_obj) },
    };
    
    STATIC MP_DEFINE_CONST_DICT(usocket_locals_dict, usocket_locals_dict_table);
    
    STATIC const mp_stream_p_t usocket_stream_p = {
        .read = socket_read,
        .write = socket_write,
    };
    
    const mp_obj_type_t mp_type_socket = {
        { &mp_type_type },
        .name = MP_QSTR_socket,
        .print = socket_print,
        .make_new = socket_make_new,
        .getiter = NULL,
        .iternext = NULL,
        .protocol = &usocket_stream_p,
        .locals_dict = (mp_obj_dict_t*)&usocket_locals_dict,
    };
    
    #if MICROPY_SOCKET_EXTRA
    STATIC mp_obj_t mod_socket_htons(mp_obj_t arg) {
        return MP_OBJ_NEW_SMALL_INT(htons(MP_OBJ_SMALL_INT_VALUE(arg)));
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_socket_htons_obj, mod_socket_htons);
    
    
    STATIC mp_obj_t mod_socket_gethostbyname(mp_obj_t arg) {
        assert(MP_OBJ_IS_TYPE(arg, &mp_type_str));
        const char *s = mp_obj_str_get_str(arg);
        struct hostent *h = gethostbyname(s);
        if (h == NULL) {
            // CPython: socket.herror
            mp_raise_OSError(h_errno);
        }
        assert(h->h_length == 4);
        return mp_obj_new_int(*(int*)*h->h_addr_list);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_socket_gethostbyname_obj, mod_socket_gethostbyname);
    #endif // MICROPY_SOCKET_EXTRA
    
    #define BINADDR_MAX_LEN sizeof(struct in6_addr)
    STATIC mp_obj_t mod_socket_inet_pton(mp_obj_t family_in, mp_obj_t addr_in) {
        int family = mp_obj_get_int(family_in);
        byte binaddr[BINADDR_MAX_LEN];
        int r = inet_pton(family, mp_obj_str_get_str(addr_in), binaddr);
        RAISE_ERRNO(r, errno);
        if (r == 0) {
            mp_raise_OSError(MP_EINVAL);
        }
        int binaddr_len = 0;
        switch (family) {
            case AF_INET:
                binaddr_len = sizeof(struct in_addr);
                break;
            case AF_INET6:
                binaddr_len = sizeof(struct in6_addr);
                break;
        }
        return mp_obj_new_bytes(binaddr, binaddr_len);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_socket_inet_pton_obj, mod_socket_inet_pton);
    
    STATIC mp_obj_t mod_socket_inet_ntop(mp_obj_t family_in, mp_obj_t binaddr_in) {
        int family = mp_obj_get_int(family_in);
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(binaddr_in, &bufinfo, MP_BUFFER_READ);
        vstr_t vstr;
        vstr_init_len(&vstr, family == AF_INET ? INET_ADDRSTRLEN : INET6_ADDRSTRLEN);
        if (inet_ntop(family, bufinfo.buf, vstr.buf, vstr.len) == NULL) {
            mp_raise_OSError(errno);
        }
        vstr.len = strlen(vstr.buf);
        return mp_obj_new_str_from_vstr(&mp_type_str, &vstr);
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_2(mod_socket_inet_ntop_obj, mod_socket_inet_ntop);
    
    STATIC mp_obj_t mod_socket_getaddrinfo(size_t n_args, const mp_obj_t *args) {
        // TODO: Implement all args
        assert(n_args >= 2 && n_args <= 4);
        assert(MP_OBJ_IS_STR(args[0]));
    
        const char *host = mp_obj_str_get_str(args[0]);
        const char *serv = NULL;
        struct addrinfo hints;
        char buf[6];
        memset(&hints, 0, sizeof(hints));
        // getaddrinfo accepts port in string notation, so however
        // it may seem stupid, we need to convert int to str
        if (MP_OBJ_IS_SMALL_INT(args[1])) {
            unsigned port = (unsigned short)MP_OBJ_SMALL_INT_VALUE(args[1]);
            snprintf(buf, sizeof(buf), "%u", port);
            serv = buf;
            hints.ai_flags = AI_NUMERICSERV;
    #ifdef __UCLIBC_MAJOR__
    #if __UCLIBC_MAJOR__ == 0 && (__UCLIBC_MINOR__ < 9 || (__UCLIBC_MINOR__ == 9 && __UCLIBC_SUBLEVEL__ <= 32))
    // "warning" requires -Wno-cpp which is a relatively new gcc option, so we choose not to use it.
    //#warning Working around uClibc bug with numeric service name
            // Older versions og uClibc have bugs when numeric ports in service
            // arg require also hints.ai_socktype (or hints.ai_protocol) != 0
            // This actually was fixed in 0.9.32.1, but uClibc doesn't allow to
            // test for that.
            // http://git.uclibc.org/uClibc/commit/libc/inet/getaddrinfo.c?id=bc3be18145e4d5
            // Note that this is crude workaround, precluding UDP socket addresses
            // to be returned. TODO: set only if not set by Python args.
            hints.ai_socktype = SOCK_STREAM;
    #endif
    #endif
        } else {
            serv = mp_obj_str_get_str(args[1]);
        }
    
        if (n_args > 2) {
            hints.ai_family = MP_OBJ_SMALL_INT_VALUE(args[2]);
            if (n_args > 3) {
                hints.ai_socktype = MP_OBJ_SMALL_INT_VALUE(args[3]);
            }
        }
    
        struct addrinfo *addr_list;
        int res = getaddrinfo(host, serv, &hints, &addr_list);
    
        if (res != 0) {
            // CPython: socket.gaierror
            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_OSError, "[addrinfo error %d]", res));
        }
        assert(addr_list);
    
        mp_obj_t list = mp_obj_new_list(0, NULL);
        for (struct addrinfo *addr = addr_list; addr; addr = addr->ai_next) {
            mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(5, NULL));
            t->items[0] = MP_OBJ_NEW_SMALL_INT(addr->ai_family);
            t->items[1] = MP_OBJ_NEW_SMALL_INT(addr->ai_socktype);
            t->items[2] = MP_OBJ_NEW_SMALL_INT(addr->ai_protocol);
            // "canonname will be a string representing the canonical name of the host
            // if AI_CANONNAME is part of the flags argument; else canonname will be empty." ??
            if (addr->ai_canonname) {
                t->items[3] = MP_OBJ_NEW_QSTR(qstr_from_str(addr->ai_canonname));
            } else {
                t->items[3] = mp_const_none;
            }
            t->items[4] = mp_obj_new_bytearray(addr->ai_addrlen, addr->ai_addr);
            mp_obj_list_append(list, MP_OBJ_FROM_PTR(t));
        }
        freeaddrinfo(addr_list);
        return list;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_socket_getaddrinfo_obj, 2, 6, mod_socket_getaddrinfo);
    
    STATIC mp_obj_t mod_socket_sockaddr(mp_obj_t sockaddr_in) {
        mp_buffer_info_t bufinfo;
        mp_get_buffer_raise(sockaddr_in, &bufinfo, MP_BUFFER_READ);
        switch (((struct sockaddr*)bufinfo.buf)->sa_family) {
            case AF_INET: {
                struct sockaddr_in *sa = (struct sockaddr_in*)bufinfo.buf;
                mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(3, NULL));
                t->items[0] = MP_OBJ_NEW_SMALL_INT(AF_INET);
                t->items[1] = mp_obj_new_bytes((byte*)&sa->sin_addr, sizeof(sa->sin_addr));
                t->items[2] = MP_OBJ_NEW_SMALL_INT(ntohs(sa->sin_port));
                return MP_OBJ_FROM_PTR(t);
            }
            case AF_INET6: {
                struct sockaddr_in6 *sa = (struct sockaddr_in6*)bufinfo.buf;
                mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(5, NULL));
                t->items[0] = MP_OBJ_NEW_SMALL_INT(AF_INET6);
                t->items[1] = mp_obj_new_bytes((byte*)&sa->sin6_addr, sizeof(sa->sin6_addr));
                t->items[2] = MP_OBJ_NEW_SMALL_INT(ntohs(sa->sin6_port));
                t->items[3] = MP_OBJ_NEW_SMALL_INT(ntohl(sa->sin6_flowinfo));
                t->items[4] = MP_OBJ_NEW_SMALL_INT(ntohl(sa->sin6_scope_id));
                return MP_OBJ_FROM_PTR(t);
            }
            default: {
                struct sockaddr *sa = (struct sockaddr*)bufinfo.buf;
                mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(2, NULL));
                t->items[0] = MP_OBJ_NEW_SMALL_INT(sa->sa_family);
                t->items[1] = mp_obj_new_bytes((byte*)sa->sa_data, bufinfo.len - offsetof(struct sockaddr, sa_data));
                return MP_OBJ_FROM_PTR(t);
            }
        }
        return mp_const_none;
    }
    STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_socket_sockaddr_obj, mod_socket_sockaddr);
    
    STATIC const mp_rom_map_elem_t mp_module_socket_globals_table[] = {
        { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_usocket) },
        { MP_ROM_QSTR(MP_QSTR_socket), MP_ROM_PTR(&mp_type_socket) },
        { MP_ROM_QSTR(MP_QSTR_getaddrinfo), MP_ROM_PTR(&mod_socket_getaddrinfo_obj) },
        { MP_ROM_QSTR(MP_QSTR_inet_pton), MP_ROM_PTR(&mod_socket_inet_pton_obj) },
        { MP_ROM_QSTR(MP_QSTR_inet_ntop), MP_ROM_PTR(&mod_socket_inet_ntop_obj) },
        { MP_ROM_QSTR(MP_QSTR_sockaddr), MP_ROM_PTR(&mod_socket_sockaddr_obj) },
    #if MICROPY_SOCKET_EXTRA
        { MP_ROM_QSTR(MP_QSTR_htons), MP_ROM_PTR(&mod_socket_htons_obj) },
        { MP_ROM_QSTR(MP_QSTR_gethostbyname), MP_ROM_PTR(&mod_socket_gethostbyname_obj) },
    #endif
    
    #define C(name) { MP_ROM_QSTR(MP_QSTR_ ## name), MP_ROM_INT(name) }
        C(AF_UNIX),
        C(AF_INET),
        C(AF_INET6),
        C(SOCK_STREAM),
        C(SOCK_DGRAM),
        C(SOCK_RAW),
    
        C(MSG_DONTROUTE),
        C(MSG_DONTWAIT),
    
        C(SOL_SOCKET),
        C(SO_BROADCAST),
        C(SO_ERROR),
        C(SO_KEEPALIVE),
        C(SO_LINGER),
        C(SO_REUSEADDR),
    #undef C
    };
    
    STATIC MP_DEFINE_CONST_DICT(mp_module_socket_globals, mp_module_socket_globals_table);
    
    const mp_obj_module_t mp_module_socket = {
        .base = { &mp_type_module },
        .globals = (mp_obj_dict_t*)&mp_module_socket_globals,
    };