/*
* open the file by sending the "name" and "oflag" to the
* connection server and reading a file descriptor back.
*/
int csopen(char *name, int oflag)
{
pid_t pid;
int len;
char buf[10];
struct iovec iov[3];
static int fd[2] = { -1, -1 };
if (fd[0] < 0) { /* fork/exec our open server first time */
/*
* fd_pipe() is defined in figure 17-2.c
*/
if (fd_pipe(fd) < 0) {
err_ret("fd_pipe error");
return -1;
}
if ((pid = fork()) < 0) {
err_ret("fork error");
return -1;
} else if (pid == 0) { /* child */
close(fd[0]);
if (fd[1] != STDIN_FILENO &&
dup2(fd[1], STDIN_FILENO) != STDIN_FILENO)
err_sys("dup2 error to stdin");
if (fd[1] != STDOUT_FILENO &&
dup2(fd[1], STDOUT_FILENO) != STDOUT_FILENO)
err_sys("dup2 error to stdout");
/*
* exec family returns only if error
*/
if (execl("./opend", "opend", (char *)0) < 0)
err_sys("execl error");
}
/* parent */
close(fd[1]);
}
sprintf(buf, " %d", oflag); /* oflag to ascii */
iov[0].iov_base = CL_OPEN " "; /* string concatenation */
iov[0].iov_len = strlen(CL_OPEN) + 1;
iov[1].iov_base = name;
iov[1].iov_len = strlen(name);
iov[2].iov_base = buf;
iov[2].iov_len = strlen(buf) + 1; /* +1 for null at end of buf */
len = iov[0].iov_len + iov[1].iov_len + iov[2].iov_len;
if (writev(fd[0], &iov[0], 3) != len) {
err_ret("writev error");
return -1;
}
/*
* read descriptor, returned errors handled by write()
* recv_fd() is defined in 17-14.c
*/
return (recv_fd(fd[0], write));
}
void
do_driver(char *driver)
{
pid_t child;
int pipe[2];
/*
* Create a full-duplex pipe to communicate with the driver.
*/
if (fd_pipe(pipe) < 0)
err_sys("can't create stream pipe");
if ((child = fork()) < 0) {
err_sys("fork error");
} else if (child == 0) { /* child */
close(pipe[1]);
/* stdin for driver */
if (dup2(pipe[0], STDIN_FILENO) != STDIN_FILENO)
err_sys("dup2 error to stdin");
/* stdout for driver */
if (dup2(pipe[0], STDOUT_FILENO) != STDOUT_FILENO)
err_sys("dup2 error to stdout");
if (pipe[0] != STDIN_FILENO && pipe[0] != STDOUT_FILENO)
close(pipe[0]);
/* leave stderr for driver alone */
execlp(driver, driver, (char *)0);
err_sys("execlp error for: %s", driver);
}
close(pipe[0]); /* parent */
if (dup2(pipe[1], STDIN_FILENO) != STDIN_FILENO)
err_sys("dup2 error to stdin");
if (dup2(pipe[1], STDOUT_FILENO) != STDOUT_FILENO)
err_sys("dup2 error to stdout");
if (pipe[1] != STDIN_FILENO && pipe[1] != STDOUT_FILENO)
close(pipe[1]);
/*
* Parent returns, but with stdin and stdout connected
* to the driver.
*/
}
int /* returns 0 if all OK, -1 if error (with errno set) */
ns_pipe(const char *name, int fd[2])
{
int len;
struct sockaddr_un unix_addr;
if (fd_pipe(fd) < 0) /* create unnamed stream pipe */
return (-1);
unlink(name); /* remove the name, if it already exists */
memset(&unix_addr, 0, sizeof(unix_addr));
unix_addr.sun_family = AF_UNIX;
strcpy(unix_addr.sun_path, name);
len = strlen(unix_addr.sun_path) + sizeof(unix_addr.sun_family);
return (bind(fd[0], (struct sockaddr *)&unix_addr, len));
/* fd[0] has the name bound to it */
}
/* evaluate a pipeline (3.9.2)
* ----------------------------------------------------------------------- */
int eval_pipeline(struct eval *e, struct npipe *npipe) {
struct job *job;
union node *node;
struct fdstack st;
unsigned int n;
int pid = 0;
int prevfd = -1;
int status = -1;
/* job = (e->flags & E_JCTL) ? job_new(npipe->ncmd) : NULL;*/
job = job_new(npipe->ncmd);
if(job == NULL) {
buffer_puts(fd_err->w, "no job control");
buffer_putnlflush(fd_err->w);
}
for(node = npipe->cmds; node; node = node->list.next) {
fdstack_push(&st);
/* if there was a previous command we read input from pipe */
if(prevfd >= 0) {
struct fd *in;
fd_alloca(in);
fd_push(in, STDIN_FILENO, FD_READ|FD_PIPE);
fd_setfd(in, prevfd);
}
/* if it isn't the last command we have to create a pipe
to pass output to the next command */
if(node->list.next) {
struct fd *out;
fd_alloca(out);
fd_push(out, STDOUT_FILENO, FD_WRITE|FD_PIPE);
prevfd = fd_pipe(out);
if(prevfd == -1) {
close(prevfd);
sh_error("pipe creation failed");
}
}
if((n = fdstack_npipes(FD_HERE|FD_SUBST)))
fdstack_pipe(n, fdstack_alloc(n));
pid = job_fork(job, node, npipe->bgnd);
if(!pid) {
/* no job control for commands inside pipe */
/* e->mode &= E_JCTL;*/
/* exit after evaluating this subtree */
exit(eval_tree(e, node, E_EXIT));
}
fdstack_pop(&st);
fdstack_data();
}
if(!npipe->bgnd) {
job_wait(job, 0, &status, 0);
}
/* if(job)
shell_free(job);*/
return WEXITSTATUS(status);
}
