libaltos: Mac OS X cannot use 'poll(2)' on serial lines.

Who ships this stuff, anyway? Instead of blocking, we'll poll every 100ms now,
otherwise, we won't be able to abort the read when the device is closed. Yay!

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 86 insertions, 48 deletions

diff --git a/ao-tools/libaltos/libaltos.c b/ao-tools/libaltos/libaltos.c
index 93c483d1..65cd6c1a 100644
--- a/ao-tools/libaltos/libaltos.c
+++ b/ao-tools/libaltos/libaltos.c
@@ -21,6 +21,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+#define USE_POLL
+
 PUBLIC int
 altos_init(void)
 {
@@ -33,6 +35,9 @@ altos_fini(void)
 }
 
 #ifdef DARWIN
+
+#undef USE_POLL
+
 /* Mac OS X don't have strndup even if _GNU_SOURCE is defined */
 static char *
 altos_strndup (const char *s, size_t n)
@@ -471,20 +476,21 @@ altos_list_finish(struct altos_list *list)
 #include <fcntl.h>
 #include <termios.h>
 #include <errno.h>
-#include <pthread.h>
 
 #define USB_BUF_SIZE	64
 
 struct altos_file {
 	int				fd;
+#ifdef USE_POLL
 	int				pipe[2];
+#else
+	int				out_fd;
+#endif
 	unsigned char			out_data[USB_BUF_SIZE];
 	int				out_used;
 	unsigned char			in_data[USB_BUF_SIZE];
 	int				in_used;
 	int				in_read;
-	pthread_mutex_t			putc_mutex;
-	pthread_mutex_t			getc_mutex;
 };
 
 struct altos_file *
@@ -497,32 +503,54 @@ altos_open(struct altos_device *device)
 	if (!file)
 		return NULL;
 
-	pipe(file->pipe);
+	printf("open %s\n", device->path);
 	file->fd = open(device->path, O_RDWR | O_NOCTTY);
+	printf("opened %d\n", file->fd);
 	if (file->fd < 0) {
 		perror(device->path);
 		free(file);
 		return NULL;
 	}
+#ifdef USE_POLL
+	pipe(file->pipe);
+#else
+	file->out_fd = open(device->path, O_RDWR | O_NOCTTY);
+	if (file->out_fd < 0) {
+		perror(device->path);
+		close(file->fd);
+		free(file);
+		return NULL;
+	}
+#endif
 	ret = tcgetattr(file->fd, &term);
 	if (ret < 0) {
 		perror("tcgetattr");
 		close(file->fd);
+#ifndef USE_POLL
+		close(file->out_fd);
+#endif
 		free(file);
 		return NULL;
 	}
 	cfmakeraw(&term);
+#ifdef USE_POLL
 	term.c_cc[VMIN] = 1;
 	term.c_cc[VTIME] = 0;
+#else
+	term.c_cc[VMIN] = 0;
+	term.c_cc[VTIME] = 1;
+#endif
 	ret = tcsetattr(file->fd, TCSAFLUSH, &term);
 	if (ret < 0) {
 		perror("tcsetattr");
 		close(file->fd);
+#ifndef USE_POLL
+		close(file->out_fd);
+#endif
 		free(file);
 		return NULL;
 	}
-	pthread_mutex_init(&file->putc_mutex,NULL);
-	pthread_mutex_init(&file->getc_mutex,NULL);
+	printf("running %d\n", file->fd);
 	return file;
 }
 
@@ -532,7 +560,13 @@ altos_close(struct altos_file *file)
 	if (file->fd != -1) {
 		int	fd = file->fd;
 		file->fd = -1;
+#ifdef USE_POLL
 		write(file->pipe[1], "\r", 1);
+#else
+		close(file->out_fd);
+		file->out_fd = -1;
+#endif
+		printf("close %d\n", fd);
 		close(fd);
 	}
 }
@@ -544,16 +578,20 @@ altos_free(struct altos_file *file)
 	free(file);
 }
 
-static int
-_altos_flush(struct altos_file *file)
+int
+altos_flush(struct altos_file *file)
 {
 	while (file->out_used) {
 		int	ret;
 
 		if (file->fd < 0)
 			return -EBADF;
-		fflush(stdout);
+		printf("write %d\n", file->out_used);
+#ifdef USE_POLL
 		ret = write (file->fd, file->out_data, file->out_used);
+#else
+		ret = write (file->out_fd, file->out_data, file->out_used);
+#endif
 		if (ret < 0)
 			return -errno;
 		if (ret) {
@@ -562,6 +600,7 @@ _altos_flush(struct altos_file *file)
 			file->out_used -= ret;
 		}
 	}
+	return 0;
 }
 
 int
@@ -569,79 +608,81 @@ altos_putchar(struct altos_file *file, char c)
 {
 	int	ret;
 
-	pthread_mutex_lock(&file->putc_mutex);
 	if (file->out_used == USB_BUF_SIZE) {
-		ret = _altos_flush(file);
+		ret = altos_flush(file);
 		if (ret) {
-			pthread_mutex_unlock(&file->putc_mutex);
 			return ret;
 		}
 	}
 	file->out_data[file->out_used++] = c;
 	ret = 0;
 	if (file->out_used == USB_BUF_SIZE)
-		ret = _altos_flush(file);
-	pthread_mutex_unlock(&file->putc_mutex);
+		ret = altos_flush(file);
 	return 0;
 }
 
-int
-altos_flush(struct altos_file *file)
-{
-	int ret;
-	pthread_mutex_lock(&file->putc_mutex);
-	ret = _altos_flush(file);
-	pthread_mutex_unlock(&file->putc_mutex);
-	return ret;
-}
-
-
+#ifdef USE_POLL
 #include <poll.h>
+#endif
 
 int
-altos_getchar(struct altos_file *file, int timeout)
+altos_fill(struct altos_file *file, int timeout)
 {
 	int		ret;
+#ifdef USE_POLL
 	struct pollfd	fd[2];
+#endif
 
 	if (timeout == 0)
 		timeout = -1;
-	pthread_mutex_lock(&file->getc_mutex);
-	fd[0].fd = file->fd;
-	fd[0].events = POLLIN;
-	fd[1].fd = file->pipe[0];
-	fd[1].events = POLLIN;
 	while (file->in_read == file->in_used) {
-		if (file->fd < 0) {
-			pthread_mutex_unlock(&file->getc_mutex);
+		if (file->fd < 0)
 			return LIBALTOS_ERROR;
-		}
-		altos_flush(file);
-
+#ifdef USE_POLL
+		fd[0].fd = file->fd;
+		fd[0].events = POLLIN;
+		fd[1].fd = file->pipe[0];
+		fd[1].events = POLLIN;
 		ret = poll(fd, 2, timeout);
 		if (ret < 0) {
 			perror("altos_getchar");
-			pthread_mutex_unlock(&file->getc_mutex);
 			return LIBALTOS_ERROR;
 		}
-		if (ret == 0) {
-			pthread_mutex_unlock(&file->getc_mutex);
+		if (ret == 0)
 			return LIBALTOS_TIMEOUT;
-		}
-		if (fd[0].revents & POLLIN) {
+		if (fd[0].revents & POLLIN)
+#endif
+		{
 			ret = read(file->fd, file->in_data, USB_BUF_SIZE);
+			if (ret)
+				printf("read %d\n", ret);
 			if (ret < 0) {
 				perror("altos_getchar");
-				pthread_mutex_unlock(&file->getc_mutex);
 				return LIBALTOS_ERROR;
 			}
 			file->in_read = 0;
 			file->in_used = ret;
+#ifndef USE_POLL
+			if (ret == 0 && timeout > 0)
+				return LIBALTOS_TIMEOUT;
+#endif
 		}
 	}
-	ret = file->in_data[file->in_read++];
-	pthread_mutex_unlock(&file->getc_mutex);
-	return ret;
+	return 0;
+}
+
+int
+altos_getchar(struct altos_file *file, int timeout)
+{
+	int	ret;
+	while (file->in_read == file->in_used) {
+		if (file->fd < 0)
+			return LIBALTOS_ERROR;
+		ret = altos_fill(file, timeout);
+		if (ret)
+			return ret;
+	}
+	return file->in_data[file->in_read++];
 }
 
 #endif /* POSIX_TTY */
@@ -919,9 +960,6 @@ altos_getchar(struct altos_file *file, int timeout)
 {
 	int	ret;
 	while (file->in_read == file->in_used) {
-		ret = altos_flush(file);
-		if (ret)
-			return ret;
 		if (file->handle == INVALID_HANDLE_VALUE)
 			return LIBALTOS_ERROR;
 		ret = altos_fill(file, timeout);