Files
Arquivotheca.Solaris-2.5/uts/common/syscall/pipe.c
seta75D 7c4988eac0 Init
2021-10-11 19:38:01 -03:00

153 lines
2.8 KiB
C
Executable File

/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/* THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T */
/* The copyright notice above does not evidence any */
/* actual or intended publication of such source code. */
#ident "@(#)pipe.c 1.21 94/09/28 SMI" /* from SVr4.0 1.11 */
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/cred.h>
#include <sys/user.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/stream.h>
#include <sys/strsubr.h>
#include <sys/errno.h>
#include <sys/debug.h>
#include <sys/fs/fifonode.h>
/*
* This is the loadable module wrapper.
*/
#include <sys/modctl.h>
#include <sys/syscall.h>
char _depends_on[] = "fs/fifofs";
longlong_t pipe();
static struct sysent pipe_sysent = {
0,
SE_NOUNLOAD | SE_ARGC,
(int (*)())pipe
};
/*
* Module linkage information for the kernel.
*/
extern struct mod_ops mod_syscallops;
static struct modlsys modlsys = {
&mod_syscallops,
"Pipe",
&pipe_sysent
};
static struct modlinkage modlinkage = {
MODREV_1, (void *)&modlsys, NULL
};
_init()
{
return (mod_install(&modlinkage));
}
_fini()
{
return (EBUSY);
}
_info(modinfop)
struct modinfo *modinfop;
{
return (mod_info(&modlinkage, modinfop));
}
void
pipeinit()
{
}
/*
* pipe(2) system call.
* Create a pipe by connecting two streams together. Associate
* each end of the pipe with a vnode, a file descriptor and
* one of the streams.
*/
longlong_t
pipe()
{
vnode_t *vp1, *vp2;
struct file *fp1, *fp2;
int error = 0;
int fd1, fd2;
rval_t r;
/*
* Allocate and initialize two vnodes.
*/
makepipe(&vp1, &vp2);
/*
* Allocate and initialize two file table entries and two
* file pointers. Each file pointer is open for read and
* write.
*/
if (error = falloc(vp1, FWRITE|FREAD, &fp1, &fd1)) {
VN_RELE(vp1);
VN_RELE(vp2);
return ((longlong_t)set_errno(error));
}
if (error = falloc(vp2, FWRITE|FREAD, &fp2, &fd2))
goto out2;
/*
* Create two stream heads and attach to each vnode.
*/
if (error = fifo_stropen(&vp1, FWRITE|FREAD, fp1->f_cred, 0))
goto out;
if (error = fifo_stropen(&vp2, FWRITE|FREAD, fp2->f_cred, 0)) {
(void) VOP_CLOSE(vp1, FWRITE|FREAD, 0, (offset_t)0,
fp1->f_cred);
goto out;
}
str_mate(strvp2wq(vp1), strvp2wq(vp2));
VTOF(vp1)->fn_ino = VTOF(vp2)->fn_ino = fifogetid();
/*
* Now fill in the entries that falloc reserved
*/
mutex_exit(&fp1->f_tlock);
mutex_exit(&fp2->f_tlock);
setf(fd1, fp1);
setf(fd2, fp2);
/*
* Return the file descriptors to the user. They now
* point to two different vnodes which have different
* stream heads.
*/
r.r_val1 = fd1;
r.r_val2 = fd2;
return (r.r_vals);
out:
unfalloc(fp2);
setf(fd2, NULLFP);
out2:
unfalloc(fp1);
setf(fd1, NULLFP);
VN_RELE(vp1);
VN_RELE(vp2);
return ((longlong_t)set_errno(error));
}