File: [local] / src / usr.bin / aucat / Attic / pipe.c (download)
Revision 1.8, Sun Jan 10 21:47:41 2010 UTC (14 years, 4 months ago) by ratchov
Branch: MAIN
CVS Tags: OPENBSD_4_7_BASE, OPENBSD_4_7 Changes since 1.7: +15 -0 lines
Add traces to help tracking subtle timing bugs often causing
underuns and overruns; such bugs are hard to debug with ktrace
or a debugger. They are also handy to debug or monitor code
using aucat.
To enable traces, compile aucat with ``make DEBUG=-DDEBUG'' and
use the -d option multiple times.
ok jakemsr
|
/*
* Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/time.h>
#include <sys/types.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "conf.h"
#include "pipe.h"
#ifdef DEBUG
#include "dbg.h"
#endif
struct fileops pipe_ops = {
"pipe",
sizeof(struct pipe),
pipe_close,
pipe_read,
pipe_write,
NULL, /* start */
NULL, /* stop */
pipe_nfds,
pipe_pollfd,
pipe_revents
};
struct pipe *
pipe_new(struct fileops *ops, int fd, char *name)
{
struct pipe *f;
f = (struct pipe *)file_new(ops, name, 1);
if (f == NULL)
return NULL;
f->fd = fd;
return f;
}
unsigned
pipe_read(struct file *file, unsigned char *data, unsigned count)
{
struct pipe *f = (struct pipe *)file;
int n;
while ((n = read(f->fd, data, count)) < 0) {
f->file.state &= ~FILE_ROK;
if (errno == EAGAIN) {
#ifdef DEBUG
if (debug_level >= 4) {
file_dbg(&f->file);
dbg_puts(": reading blocked\n");
}
#endif
} else {
warn("%s", f->file.name);
file_eof(&f->file);
}
return 0;
}
if (n == 0) {
f->file.state &= ~FILE_ROK; /* XXX: already cleared in file_eof */
file_eof(&f->file);
return 0;
}
return n;
}
unsigned
pipe_write(struct file *file, unsigned char *data, unsigned count)
{
struct pipe *f = (struct pipe *)file;
int n;
while ((n = write(f->fd, data, count)) < 0) {
f->file.state &= ~FILE_WOK;
if (errno == EAGAIN) {
#ifdef DEBUG
if (debug_level >= 4) {
file_dbg(&f->file);
dbg_puts(": writing blocked\n");
}
#endif
} else {
if (errno != EPIPE)
warn("%s", f->file.name);
file_hup(&f->file);
}
return 0;
}
return n;
}
int
pipe_nfds(struct file *file) {
return 1;
}
int
pipe_pollfd(struct file *file, struct pollfd *pfd, int events)
{
struct pipe *f = (struct pipe *)file;
pfd->fd = f->fd;
pfd->events = events;
return (events != 0) ? 1 : 0;
}
int
pipe_revents(struct file *f, struct pollfd *pfd)
{
return pfd->revents;
}
void
pipe_close(struct file *file)
{
struct pipe *f = (struct pipe *)file;
close(f->fd);
}