diff options
Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/netif/slipif.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/netif/slipif.c | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/netif/slipif.c b/tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/netif/slipif.c new file mode 100644 index 0000000000..c19333dd70 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/netif/slipif.c @@ -0,0 +1,367 @@ +/** + * @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 <magnus.ivarsson(at)volvo.com> + */ + +/* + * This is an arch independent SLIP netif. The specific serial hooks must be + * provided by another file. They are sio_open, sio_read/sio_tryread and sio_send + */ + +#include "netif/slipif.h" +#include "lwip/opt.h" + +#if LWIP_HAVE_SLIPIF + +#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_BLOCK 1 +#define SLIP_DONTBLOCK 0 + +#define SLIP_END 0300 /* 0xC0 */ +#define SLIP_ESC 0333 /* 0xDB */ +#define SLIP_ESC_END 0334 /* 0xDC */ +#define SLIP_ESC_ESC 0335 /* 0xDD */ + +#define SLIP_MAX_SIZE 1500 + +enum slipif_recv_state { + SLIP_RECV_NORMAL, + SLIP_RECV_ESCAPE, +}; + +struct slipif_priv { + sio_fd_t sd; + /* q is the whole pbuf chain for a packet, p is the current pbuf in the chain */ + struct pbuf *p, *q; + enum slipif_recv_state state; + u16_t i, recved; +}; + +/** + * 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, ip_addr_t *ipaddr) +{ + struct slipif_priv *priv; + 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); + + priv = netif->state; + + /* Send pbuf out on the serial I/O device. */ + sio_send(SLIP_END, priv->sd); + + 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, priv->sd); + sio_send(SLIP_ESC_END, priv->sd); + break; + case SLIP_ESC: + sio_send(SLIP_ESC, priv->sd); + sio_send(SLIP_ESC_ESC, priv->sd); + break; + default: + sio_send(c, priv->sd); + break; + } + } + } + sio_send(SLIP_END, priv->sd); + return ERR_OK; +} + +/** + * Static function for easy use of blockig or non-blocking + * sio_read + * + * @param fd serial device handle + * @param data pointer to data buffer for receiving + * @param len maximum length (in bytes) of data to receive + * @param block if 1, call sio_read; if 0, call sio_tryread + * @return return value of sio_read of sio_tryread + */ +static u32_t +slip_sio_read(sio_fd_t fd, u8_t* data, u32_t len, u8_t block) +{ + if (block) { + return sio_read(fd, data, len); + } else { + return sio_tryread(fd, data, len); + } +} + +/** + * Handle the incoming SLIP stream character by character + * + * Poll the serial layer by calling sio_read() or sio_tryread(). + * + * @param netif the lwip network interface structure for this slipif + * @param block if 1, block until data is received; if 0, return when all data + * from the buffer is received (multiple calls to this function will + * return a complete packet, NULL is returned before - used for polling) + * @return The IP packet when SLIP_END is received + */ +static struct pbuf * +slipif_input(struct netif *netif, u8_t block) +{ + struct slipif_priv *priv; + u8_t c; + struct pbuf *t; + + LWIP_ASSERT("netif != NULL", (netif != NULL)); + LWIP_ASSERT("netif->state != NULL", (netif->state != NULL)); + + priv = netif->state; + + while (slip_sio_read(priv->sd, &c, 1, block) > 0) { + switch (priv->state) { + case SLIP_RECV_NORMAL: + switch (c) { + case SLIP_END: + if (priv->recved > 0) { + /* Received whole packet. */ + /* Trim the pbuf to the size of the received packet. */ + pbuf_realloc(priv->q, priv->recved); + + LINK_STATS_INC(link.recv); + + LWIP_DEBUGF(SLIP_DEBUG, ("slipif: Got packet\n")); + t = priv->q; + priv->p = priv->q = NULL; + priv->i = priv->recved = 0; + return t; + } + continue; + case SLIP_ESC: + priv->state = SLIP_RECV_ESCAPE; + continue; + } + break; + case SLIP_RECV_ESCAPE: + switch (c) { + case SLIP_ESC_END: + c = SLIP_END; + break; + case SLIP_ESC_ESC: + c = SLIP_ESC; + break; + } + priv->state = SLIP_RECV_NORMAL; + /* FALLTHROUGH */ + } + + /* byte received, packet not yet completely received */ + if (priv->p == NULL) { + /* allocate a new pbuf */ + LWIP_DEBUGF(SLIP_DEBUG, ("slipif_input: alloc\n")); + priv->p = pbuf_alloc(PBUF_LINK, (PBUF_POOL_BUFSIZE - PBUF_LINK_HLEN), PBUF_POOL); + + if (priv->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 (priv->q != NULL) { + /* 'chain' the pbuf to the existing chain */ + pbuf_cat(priv->q, priv->p); + } else { + /* p is the first pbuf in the chain */ + priv->q = priv->p; + } + } + + /* this automatically drops bytes if > SLIP_MAX_SIZE */ + if ((priv->p != NULL) && (priv->recved <= SLIP_MAX_SIZE)) { + ((u8_t *)priv->p->payload)[priv->i] = c; + priv->recved++; + priv->i++; + if (priv->i >= priv->p->len) { + /* on to the next pbuf */ + priv->i = 0; + if (priv->p->next != NULL && priv->p->next->len > 0) { + /* p is a chain, on to the next in the chain */ + priv->p = priv->p->next; + } else { + /* p is a single pbuf, set it to NULL so next time a new + * pbuf is allocated */ + priv->p = NULL; + } + } + } + } + + 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_thread(void *nf) +{ + struct pbuf *p; + struct netif *netif = (struct netif *)nf; + + while (1) { + p = slipif_input(netif, SLIP_BLOCK); + 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_MEM if no memory could be allocated, + * 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) +{ + struct slipif_priv *priv; + + LWIP_DEBUGF(SLIP_DEBUG, ("slipif_init: netif->num=%"U16_F"\n", (u16_t)netif->num)); + + /* Allocate private data */ + priv = mem_malloc(sizeof(struct slipif_priv)); + if (!priv) { + return ERR_MEM; + } + + netif->name[0] = 's'; + netif->name[1] = 'l'; + netif->output = slipif_output; + netif->mtu = SLIP_MAX_SIZE; + netif->flags |= NETIF_FLAG_POINTTOPOINT; + + /* Try to open the serial port (netif->num contains the port number). */ + priv->sd = sio_open(netif->num); + if (!priv->sd) { + /* Opening the serial port failed. */ + mem_free(priv); + return ERR_IF; + } + + /* Initialize private data */ + priv->p = NULL; + priv->q = NULL; + priv->state = SLIP_RECV_NORMAL; + priv->i = 0; + priv->recved = 0; + + netif->state = priv; + + /* 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_thread, netif, + SLIPIF_THREAD_STACKSIZE, SLIPIF_THREAD_PRIO); + return ERR_OK; +} + +/** + * Polls the serial device and feeds the IP layer with incoming packets. + * + * @param netif The lwip network interface structure for this slipif + */ +void +slipif_poll(struct netif *netif) +{ + struct pbuf *p; + struct slipif_priv *priv; + + LWIP_ASSERT("netif != NULL", (netif != NULL)); + LWIP_ASSERT("netif->state != NULL", (netif->state != NULL)); + + priv = netif->state; + + while ((p = slipif_input(netif, SLIP_DONTBLOCK)) != NULL) { + if (netif->input(p, netif) != ERR_OK) { + pbuf_free(p); + } + } +} + +#endif /* LWIP_HAVE_SLIPIF */ |