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Diffstat (limited to 'apps/examples/poll/poll_listener.c')
| -rw-r--r-- | apps/examples/poll/poll_listener.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/apps/examples/poll/poll_listener.c b/apps/examples/poll/poll_listener.c new file mode 100644 index 000000000..816647e34 --- /dev/null +++ b/apps/examples/poll/poll_listener.c @@ -0,0 +1,262 @@ +/**************************************************************************** + * 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; +} |