/* * Copyright (c) 2005, 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 part of the Contiki operating system. * * @(#)$Id: serial-line.c,v 1.4 2010/02/23 18:26:26 adamdunkels Exp $ */ #include "dev/serial-line.h" #include <string.h> /* for memcpy() */ #include "lib/ringbuf.h" #ifdef SERIAL_LINE_CONF_BUFSIZE #define BUFSIZE SERIAL_LINE_CONF_BUFSIZE #else /* SERIAL_LINE_CONF_BUFSIZE */ #define BUFSIZE 128 #endif /* SERIAL_LINE_CONF_BUFSIZE */ #if (BUFSIZE & (BUFSIZE - 1)) != 0 #error SERIAL_LINE_CONF_BUFSIZE must be a power of two (i.e., 1, 2, 4, 8, 16, 32, 64, ...). #error Change SERIAL_LINE_CONF_BUFSIZE in contiki-conf.h. #endif #define IGNORE_CHAR(c) (c == 0x0d) #define END 0x0a static struct ringbuf rxbuf; static uint8_t rxbuf_data[BUFSIZE]; PROCESS(serial_line_process, "Serial driver"); process_event_t serial_line_event_message; /*---------------------------------------------------------------------------*/ int serial_line_input_byte(unsigned char c) { static uint8_t overflow = 0; /* Buffer overflow: ignore until END */ if(IGNORE_CHAR(c)) { return 0; } if(!overflow) { /* Add character */ if(ringbuf_put(&rxbuf, c) == 0) { /* Buffer overflow: ignore the rest of the line */ overflow = 1; } } else { /* Buffer overflowed: * Only (try to) add terminator characters, otherwise skip */ if(c == END && ringbuf_put(&rxbuf, c) != 0) { overflow = 0; } } /* Wake up consumer process */ process_poll(&serial_line_process); return 1; } /*---------------------------------------------------------------------------*/ PROCESS_THREAD(serial_line_process, ev, data) { static char buf[BUFSIZE]; static int ptr; PROCESS_BEGIN(); serial_line_event_message = process_alloc_event(); ptr = 0; while(1) { /* Fill application buffer until newline or empty */ int c = ringbuf_get(&rxbuf); if(c == -1) { /* Buffer empty, wait for poll */ PROCESS_YIELD(); } else { if(c != END) { if(ptr < BUFSIZE-1) { buf[ptr++] = (uint8_t)c; } else { /* Ignore character (wait for EOL) */ } } else { /* Terminate */ buf[ptr++] = (uint8_t)'\0'; /* Broadcast event */ process_post(PROCESS_BROADCAST, serial_line_event_message, buf); /* Wait until all processes have handled the serial line event */ if(PROCESS_ERR_OK == process_post(PROCESS_CURRENT(), PROCESS_EVENT_CONTINUE, NULL)) { PROCESS_WAIT_EVENT_UNTIL(ev == PROCESS_EVENT_CONTINUE); } ptr = 0; } } } PROCESS_END(); } /*---------------------------------------------------------------------------*/ void serial_line_init(void) { ringbuf_init(&rxbuf, rxbuf_data, sizeof(rxbuf_data)); process_start(&serial_line_process, NULL); } /*---------------------------------------------------------------------------*/