File 0044-pacmd-don-t-enter-busy-loop-when-reading-from-stdin.patch of Package pulseaudio
From 6e064d1d6d0292d230c752b1f41034fd0754487b Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 18 Feb 2010 03:28:56 +0100
Subject: [PATCH] pacmd: don't enter busy loop when reading from stdin very early
pointed out in:
https://tango.0pointer.de/pipermail/pulseaudio-discuss/2010-January/006365.html
---
src/utils/pacmd.c | 186 ++++++++++++++++++++++++++++------------------------
1 files changed, 100 insertions(+), 86 deletions(-)
diff --git a/src/utils/pacmd.c b/src/utils/pacmd.c
index 59aae48..87661e3 100644
--- a/src/utils/pacmd.c
+++ b/src/utils/pacmd.c
@@ -45,13 +45,6 @@
int main(int argc, char*argv[]) {
- enum {
- WATCH_STDIN,
- WATCH_STDOUT,
- WATCH_SOCKET,
- N_WATCH
- };
-
pid_t pid ;
int fd = -1;
int ret = 1, i;
@@ -60,7 +53,9 @@ int main(int argc, char*argv[]) {
size_t ibuf_index, ibuf_length, obuf_index, obuf_length;
char *cli;
pa_bool_t ibuf_eof, obuf_eof, ibuf_closed, obuf_closed;
- struct pollfd pollfd[N_WATCH];
+ struct pollfd pollfd[3];
+ struct pollfd *watch_socket, *watch_stdin, *watch_stdout;
+
int stdin_type = 0, stdout_type = 0, fd_type = 0;
setlocale(LC_ALL, "");
@@ -129,32 +124,53 @@ int main(int argc, char*argv[]) {
ibuf_eof = TRUE;
}
- pa_zero(pollfd);
-
- pollfd[WATCH_STDIN].fd = STDIN_FILENO;
- pollfd[WATCH_STDOUT].fd = STDOUT_FILENO;
- pollfd[WATCH_SOCKET].fd = fd;
-
for (;;) {
+ struct pollfd *p;
+
if (ibuf_eof &&
obuf_eof &&
ibuf_length <= 0 &&
obuf_length <= 0)
break;
- pollfd[WATCH_STDIN].events = pollfd[WATCH_STDOUT].events = pollfd[WATCH_SOCKET].events = 0;
+ if (ibuf_length <= 0 && ibuf_eof && !ibuf_closed) {
+ shutdown(fd, SHUT_WR);
+ ibuf_closed = TRUE;
+ }
- if (obuf_length > 0)
- pollfd[WATCH_STDOUT].events |= POLLOUT;
- else if (!obuf_eof)
- pollfd[WATCH_SOCKET].events |= POLLIN;
+ if (obuf_length <= 0 && obuf_eof && !obuf_closed) {
+ shutdown(fd, SHUT_RD);
+ obuf_closed = TRUE;
+ }
+
+ pa_zero(pollfd);
+
+ p = pollfd;
- if (ibuf_length > 0)
- pollfd[WATCH_SOCKET].events |= POLLOUT;
- else if (!ibuf_eof)
- pollfd[WATCH_STDIN].events |= POLLIN;
+ if (ibuf_length > 0 || (!obuf_eof && obuf_length <= 0)) {
+ watch_socket = p++;
+ watch_socket->fd = fd;
+ watch_socket->events =
+ (ibuf_length > 0 ? POLLOUT : 0) |
+ (!obuf_eof && obuf_length <= 0 ? POLLIN : 0);
+ } else
+ watch_socket = NULL;
- if (poll(pollfd, N_WATCH, -1) < 0) {
+ if (!ibuf_eof && ibuf_length <= 0) {
+ watch_stdin = p++;
+ watch_stdin->fd = STDIN_FILENO;
+ watch_stdin->events = POLLIN;
+ } else
+ watch_stdin = NULL;
+
+ if (obuf_length > 0) {
+ watch_stdout = p++;
+ watch_stdout->fd = STDOUT_FILENO;
+ watch_stdout->events = POLLOUT;
+ } else
+ watch_stdout = NULL;
+
+ if (poll(pollfd, p-pollfd, -1) < 0) {
if (errno == EINTR)
continue;
@@ -163,82 +179,80 @@ int main(int argc, char*argv[]) {
goto fail;
}
- if (pollfd[WATCH_STDIN].revents & POLLIN) {
- ssize_t r;
- pa_assert(!ibuf_length);
-
- if ((r = pa_read(STDIN_FILENO, ibuf, sizeof(ibuf), &stdin_type)) <= 0) {
- if (r < 0) {
- pa_log(_("read(): %s"), strerror(errno));
- goto fail;
+ if (watch_stdin) {
+ if (watch_stdin->revents & POLLIN) {
+ ssize_t r;
+ pa_assert(ibuf_length <= 0);
+
+ if ((r = pa_read(STDIN_FILENO, ibuf, sizeof(ibuf), &stdin_type)) <= 0) {
+ if (r < 0) {
+ pa_log(_("read(): %s"), strerror(errno));
+ goto fail;
+ }
+
+ ibuf_eof = TRUE;
+ } else {
+ ibuf_length = (size_t) r;
+ ibuf_index = 0;
}
-
+ } else if (watch_stdin->revents & POLLHUP)
ibuf_eof = TRUE;
- } else {
- ibuf_length = (size_t) r;
- ibuf_index = 0;
- }
}
- if (pollfd[WATCH_SOCKET].revents & POLLIN) {
- ssize_t r;
- pa_assert(!obuf_length);
-
- if ((r = pa_read(fd, obuf, sizeof(obuf), &fd_type)) <= 0) {
- if (r < 0) {
- pa_log(_("read(): %s"), strerror(errno));
- goto fail;
+ if (watch_socket) {
+ if (watch_socket->revents & POLLIN) {
+ ssize_t r;
+ pa_assert(obuf_length <= 0);
+
+ if ((r = pa_read(fd, obuf, sizeof(obuf), &fd_type)) <= 0) {
+ if (r < 0) {
+ pa_log(_("read(): %s"), strerror(errno));
+ goto fail;
+ }
+
+ obuf_eof = TRUE;
+ } else {
+ obuf_length = (size_t) r;
+ obuf_index = 0;
}
-
+ } else if (watch_socket->revents & POLLHUP)
obuf_eof = TRUE;
- } else {
- obuf_length = (size_t) r;
- obuf_index = 0;
- }
}
- if (pollfd[WATCH_STDOUT].revents & POLLHUP) {
- obuf_eof = TRUE;
- obuf_length = 0;
- } else if (pollfd[WATCH_STDOUT].revents & POLLOUT) {
- ssize_t r;
- pa_assert(obuf_length);
-
- if ((r = pa_write(STDOUT_FILENO, obuf + obuf_index, obuf_length, &stdout_type)) < 0) {
- pa_log(_("write(): %s"), strerror(errno));
- goto fail;
- }
-
- obuf_length -= (size_t) r;
- obuf_index += obuf_index;
- }
+ if (watch_stdout) {
+ if (watch_stdout->revents & POLLHUP) {
+ obuf_eof = TRUE;
+ obuf_length = 0;
+ } else if (watch_stdout->revents & POLLOUT) {
+ ssize_t r;
+ pa_assert(obuf_length > 0);
- if (pollfd[WATCH_SOCKET].revents & POLLHUP) {
- ibuf_eof = TRUE;
- ibuf_length = 0;
- } if (pollfd[WATCH_SOCKET].revents & POLLOUT) {
- ssize_t r;
- pa_assert(ibuf_length);
+ if ((r = pa_write(STDOUT_FILENO, obuf + obuf_index, obuf_length, &stdout_type)) < 0) {
+ pa_log(_("write(): %s"), strerror(errno));
+ goto fail;
+ }
- if ((r = pa_write(fd, ibuf + ibuf_index, ibuf_length, &fd_type)) < 0) {
- pa_log(_("write(): %s"), strerror(errno));
- goto fail;
+ obuf_length -= (size_t) r;
+ obuf_index += obuf_index;
}
-
- ibuf_length -= (size_t) r;
- ibuf_index += obuf_index;
}
- if (ibuf_length <= 0 && ibuf_eof && !ibuf_closed) {
- pa_close(STDIN_FILENO);
- shutdown(fd, SHUT_WR);
- ibuf_closed = TRUE;
- }
+ if (watch_socket) {
+ if (watch_socket->revents & POLLHUP) {
+ ibuf_eof = TRUE;
+ ibuf_length = 0;
+ } if (watch_socket->revents & POLLOUT) {
+ ssize_t r;
+ pa_assert(ibuf_length > 0);
- if (obuf_length <= 0 && obuf_eof && !obuf_closed) {
- shutdown(fd, SHUT_RD);
- pa_close(STDOUT_FILENO);
- obuf_closed = TRUE;
+ if ((r = pa_write(fd, ibuf + ibuf_index, ibuf_length, &fd_type)) < 0) {
+ pa_log(_("write(): %s"), strerror(errno));
+ goto fail;
+ }
+
+ ibuf_length -= (size_t) r;
+ ibuf_index += obuf_index;
+ }
}
}
--
1.6.0.2
