X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=blobdiff_plain;f=geekos%2Fsrc%2Flwip%2Fnetif%2Fslipif.c;fp=geekos%2Fsrc%2Flwip%2Fnetif%2Fslipif.c;h=b37885932cea023e5ff86c896c2208b6862cd0b1;hp=0000000000000000000000000000000000000000;hb=ddc16b0737cf58f7aa90a69c6652cdf4090aec51;hpb=626595465a2c6987606a6bc697df65130ad8c2d3 diff --git a/geekos/src/lwip/netif/slipif.c b/geekos/src/lwip/netif/slipif.c new file mode 100644 index 0000000..b378859 --- /dev/null +++ b/geekos/src/lwip/netif/slipif.c @@ -0,0 +1,275 @@ +/** + * @file + * SLIP Interface + * + */ + +/* + * Copyright (c) 2001-2004 Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * This file is built upon the file: src/arch/rtxc/netif/sioslip.c + * + * Author: Magnus Ivarsson + */ + +/* + * This is an arch independent SLIP netif. The specific serial hooks must be + * provided by another file. They are sio_open, sio_recv and sio_send + */ + +#include "netif/slipif.h" +#include "lwip/opt.h" +#include "lwip/def.h" +#include "lwip/pbuf.h" +#include "lwip/sys.h" +#include "lwip/stats.h" +#include "lwip/snmp.h" +#include "lwip/sio.h" + +#define SLIP_END 0300 /* 0xC0 */ +#define SLIP_ESC 0333 /* 0xDB */ +#define SLIP_ESC_END 0334 /* 0xDC */ +#define SLIP_ESC_ESC 0335 /* 0xDD */ + +#define MAX_SIZE 1500 + +/** + * Send a pbuf doing the necessary SLIP encapsulation + * + * Uses the serial layer's sio_send() + * + * @param netif the lwip network interface structure for this slipif + * @param p the pbuf chaing packet to send + * @param ipaddr the ip address to send the packet to (not used for slipif) + * @return always returns ERR_OK since the serial layer does not provide return values + */ +err_t +slipif_output(struct netif *netif, struct pbuf *p, struct ip_addr *ipaddr) +{ + struct pbuf *q; + u16_t i; + u8_t c; + + LWIP_ASSERT("netif != NULL", (netif != NULL)); + LWIP_ASSERT("netif->state != NULL", (netif->state != NULL)); + LWIP_ASSERT("p != NULL", (p != NULL)); + + LWIP_UNUSED_ARG(ipaddr); + + /* Send pbuf out on the serial I/O device. */ + sio_send(SLIP_END, netif->state); + + for (q = p; q != NULL; q = q->next) { + for (i = 0; i < q->len; i++) { + c = ((u8_t *)q->payload)[i]; + switch (c) { + case SLIP_END: + sio_send(SLIP_ESC, netif->state); + sio_send(SLIP_ESC_END, netif->state); + break; + case SLIP_ESC: + sio_send(SLIP_ESC, netif->state); + sio_send(SLIP_ESC_ESC, netif->state); + break; + default: + sio_send(c, netif->state); + break; + } + } + } + sio_send(SLIP_END, netif->state); + return ERR_OK; +} + +/** + * Handle the incoming SLIP stream character by character + * + * Poll the serial layer by calling sio_recv() + * + * @param netif the lwip network interface structure for this slipif + * @return The IP packet when SLIP_END is received + */ +static struct pbuf * +slipif_input(struct netif *netif) +{ + u8_t c; + /* q is the whole pbuf chain for a packet, p is the current pbuf in the chain */ + struct pbuf *p, *q; + u16_t recved; + u16_t i; + + LWIP_ASSERT("netif != NULL", (netif != NULL)); + LWIP_ASSERT("netif->state != NULL", (netif->state != NULL)); + + q = p = NULL; + recved = i = 0; + c = 0; + + while (1) { + c = sio_recv(netif->state); + switch (c) { + case SLIP_END: + if (recved > 0) { + /* Received whole packet. */ + /* Trim the pbuf to the size of the received packet. */ + pbuf_realloc(q, recved); + + LINK_STATS_INC(link.recv); + + LWIP_DEBUGF(SLIP_DEBUG, ("slipif: Got packet\n")); + return q; + } + break; + + case SLIP_ESC: + c = sio_recv(netif->state); + switch (c) { + case SLIP_ESC_END: + c = SLIP_END; + break; + case SLIP_ESC_ESC: + c = SLIP_ESC; + break; + } + /* FALLTHROUGH */ + + default: + /* byte received, packet not yet completely received */ + if (p == NULL) { + /* allocate a new pbuf */ + LWIP_DEBUGF(SLIP_DEBUG, ("slipif_input: alloc\n")); + p = pbuf_alloc(PBUF_LINK, PBUF_POOL_BUFSIZE, PBUF_POOL); + + if (p == NULL) { + LINK_STATS_INC(link.drop); + LWIP_DEBUGF(SLIP_DEBUG, ("slipif_input: no new pbuf! (DROP)\n")); + /* don't process any further since we got no pbuf to receive to */ + break; + } + + if (q != NULL) { + /* 'chain' the pbuf to the existing chain */ + pbuf_cat(q, p); + } else { + /* p is the first pbuf in the chain */ + q = p; + } + } + + /* this automatically drops bytes if > MAX_SIZE */ + if ((p != NULL) && (recved <= MAX_SIZE)) { + ((u8_t *)p->payload)[i] = c; + recved++; + i++; + if (i >= p->len) { + /* on to the next pbuf */ + i = 0; + if (p->next != NULL && p->next->len > 0) { + /* p is a chain, on to the next in the chain */ + p = p->next; + } else { + /* p is a single pbuf, set it to NULL so next time a new + * pbuf is allocated */ + p = NULL; + } + } + } + break; + } + } + return NULL; +} + +#if !NO_SYS +/** + * The SLIP input thread. + * + * Feed the IP layer with incoming packets + * + * @param nf the lwip network interface structure for this slipif + */ +static void +slipif_loop(void *nf) +{ + struct pbuf *p; + struct netif *netif = (struct netif *)nf; + + while (1) { + p = slipif_input(netif); + if (p != NULL) { + if (netif->input(p, netif) != ERR_OK) { + pbuf_free(p); + p = NULL; + } + } + } +} +#endif /* !NO_SYS */ + +/** + * SLIP netif initialization + * + * Call the arch specific sio_open and remember + * the opened device in the state field of the netif. + * + * @param netif the lwip network interface structure for this slipif + * @return ERR_OK if serial line could be opened, + * ERR_IF is serial line couldn't be opened + * + * @note netif->num must contain the number of the serial port to open + * (0 by default) + */ +err_t +slipif_init(struct netif *netif) +{ + + LWIP_DEBUGF(SLIP_DEBUG, ("slipif_init: netif->num=%"U16_F"\n", (u16_t)netif->num)); + + netif->name[0] = 's'; + netif->name[1] = 'l'; + netif->output = slipif_output; + netif->mtu = MAX_SIZE; + netif->flags = NETIF_FLAG_POINTTOPOINT; + + /* Try to open the serial port (netif->num contains the port number). */ + netif->state = sio_open(netif->num); + if (!netif->state) { + /* Opening the serial port failed. */ + return ERR_IF; + } + + /* initialize the snmp variables and counters inside the struct netif + * ifSpeed: no assumption can be made without knowing more about the + * serial line! + */ + NETIF_INIT_SNMP(netif, snmp_ifType_slip, 0); + + /* Create a thread to poll the serial line. */ + sys_thread_new(SLIPIF_THREAD_NAME, slipif_loop, netif, SLIPIF_THREAD_STACKSIZE, SLIPIF_THREAD_PRIO); + return ERR_OK; +}