| /**************************************************************************** |
| * examples/poll/poll_listener.c |
| * |
| * Copyright (C) 2008 Gregory Nutt. All rights reserved. |
| * Author: Gregory Nutt <spudmonkey@racsa.co.cr> |
| * |
| * 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 NuttX 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 COPYRIGHT HOLDERS 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 |
| * COPYRIGHT OWNER 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. |
| * |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Included Files |
| ****************************************************************************/ |
| |
| #include <nuttx/config.h> |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <pthread.h> |
| #include <poll.h> |
| #include <fcntl.h> |
| #include <errno.h> |
| #include <debug.h> |
| |
| #include "poll_internal.h" |
| |
| /**************************************************************************** |
| * Definitions |
| ****************************************************************************/ |
| |
| #if defined(CONFIG_DEV_CONSOLE) && !defined(CONFIG_DEV_LOWCONSOLE) |
| # define HAVE_CONSOLE |
| # define NPOLLFDS 2 |
| # define CONSNDX 0 |
| # define FIFONDX 1 |
| #else |
| # undef HAVE_CONSOLE |
| # define NPOLLFDS 1 |
| # define FIFONDX 0 |
| #endif |
| |
| /**************************************************************************** |
| * Private Types |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Private Data |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Private Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: poll_listener |
| ****************************************************************************/ |
| |
| void *poll_listener(pthread_addr_t pvarg) |
| { |
| struct pollfd fds[NPOLLFDS]; |
| char buffer[64]; |
| ssize_t nbytes; |
| bool timeout; |
| bool pollin; |
| int nevents; |
| int fd; |
| int ret; |
| int i; |
| |
| /* Open the FIFO for non-blocking read */ |
| |
| message("poll_listener: Opening %s for non-blocking read\n", FIFO_PATH1); |
| fd = open(FIFO_PATH1, O_RDONLY|O_NONBLOCK); |
| if (fd < 0) |
| { |
| message("poll_listener: ERROR Failed to open FIFO %s: %d\n", |
| FIFO_PATH1, errno); |
| (void)close(fd); |
| return (void*)-1; |
| } |
| |
| /* Loop forever */ |
| |
| for (;;) |
| { |
| message("poll_listener: Calling poll()\n"); |
| |
| memset(fds, 0, sizeof(struct pollfd)*NPOLLFDS); |
| #ifdef HAVE_CONSOLE |
| fds[CONSNDX].fd = 0; |
| fds[CONSNDX].events = POLLIN; |
| fds[CONSNDX].revents = 0; |
| #endif |
| fds[FIFONDX].fd = fd; |
| fds[FIFONDX].events = POLLIN; |
| fds[FIFONDX].revents = 0; |
| |
| timeout = false; |
| pollin = false; |
| |
| ret = poll(fds, NPOLLFDS, POLL_LISTENER_DELAY); |
| |
| message("\npoll_listener: poll returned: %d\n", ret); |
| if (ret < 0) |
| { |
| message("poll_listener: ERROR poll failed: %d\n", errno); |
| } |
| else if (ret == 0) |
| { |
| message("poll_listener: Timeout\n"); |
| timeout = true; |
| } |
| else if (ret > NPOLLFDS) |
| { |
| message("poll_listener: ERROR poll reported: %d\n"); |
| } |
| else |
| { |
| pollin = true; |
| } |
| |
| nevents = 0; |
| for (i = 0; i < NPOLLFDS; i++) |
| { |
| message("poll_listener: FIFO revents[%d]=%02x\n", i, fds[i].revents); |
| if (timeout) |
| { |
| if (fds[i].revents != 0) |
| { |
| message("poll_listener: ERROR? expected revents=00, received revents[%d]=%02x\n", |
| fds[i].revents, i); |
| } |
| } |
| else if (pollin) |
| { |
| if (fds[i].revents == POLLIN) |
| { |
| nevents++; |
| } |
| else if (fds[i].revents != 0) |
| { |
| message("poll_listener: ERROR unexpected revents[i]=%02x\n", |
| i, fds[i].revents); |
| } |
| } |
| } |
| |
| if (pollin && nevents != ret) |
| { |
| message("poll_listener: ERROR found %d events, poll reported %d\n", nevents, ret); |
| } |
| |
| /* In any event, read until the pipe/serial is empty */ |
| |
| for (i = 0; i < NPOLLFDS; i++) |
| { |
| do |
| { |
| #ifdef HAVE_CONSOLE |
| /* Hack to work around the fact that the console driver on the |
| * simulator is always non-blocking. |
| */ |
| |
| if (i == CONSNDX) |
| { |
| if ((fds[CONSNDX].revents & POLLIN) != 0) |
| { |
| buffer[0] = getchar(); |
| nbytes = 1; |
| } |
| else |
| { |
| nbytes = 0; |
| } |
| } |
| else |
| #endif |
| { |
| /* The pipe works differently, it returns whatever data |
| * it has available without blocking. |
| */ |
| |
| nbytes = read(fds[i].fd, buffer, 63); |
| } |
| |
| if (nbytes <= 0) |
| { |
| if (nbytes == 0 || errno == EAGAIN) |
| { |
| if ((fds[i].revents & POLLIN) != 0) |
| { |
| message("poll_listener: ERROR no read data[%d]\n", i); |
| } |
| } |
| else if (errno != EINTR) |
| { |
| message("poll_listener: read[%d] failed: %d\n", i, errno); |
| } |
| nbytes = 0; |
| } |
| else |
| { |
| if (timeout) |
| { |
| message("poll_listener: ERROR? Poll timeout, but data read[%d]\n", i); |
| message(" (might just be a race condition)\n"); |
| } |
| |
| buffer[nbytes] = '\0'; |
| message("poll_listener: Read[%d] '%s' (%d bytes)\n", i, buffer, nbytes); |
| } |
| |
| /* Suppress error report if no read data on the next time through */ |
| |
| fds[i].revents = 0; |
| } |
| while (nbytes > 0); |
| } |
| |
| /* Make sure that everything is displayed */ |
| |
| msgflush(); |
| } |
| |
| /* Won't get here */ |
| |
| (void)close(fd); |
| return NULL; |
| } |