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/*******************************************************************************
* Copyright (c) 2004 QNX Software Systems and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* QNX Software Systems - initial API and implementation
*******************************************************************************/
#include "exec0.h"
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <libgen.h>
#include <stdlib.h>
#include <termios.h>
/* from pfind.c */
extern char *pfind(const char *name);
pid_t
exec_pty(const char *path, char *const argv[], char *const envp[],
const char *dirpath, int channels[3], const char *pts_name, int fdm)
{
int pipe2[2];
pid_t childpid;
char *full_path;
/*
* We use pfind() to check that the program exists and is an executable.
* If not pass the error up. Also execve() wants a full path.
*/
full_path = pfind(path);
if (full_path == NULL) {
fprintf(stderr, "Unable to find full path for \"%s\"\n", (path) ? path : "");
return -1;
}
/*
* Make sure we can create our pipes before forking.
*/
if (channels != NULL) {
if (pipe(pipe2) < 0) {
fprintf(stderr, "%s(%d): returning due to error: %s\n", __FUNCTION__, __LINE__, strerror(errno));
free(full_path);
return -1;
}
}
childpid = fork();
if (childpid < 0) {
fprintf(stderr, "%s(%d): returning due to error: %s\n", __FUNCTION__, __LINE__, strerror(errno));
free(full_path);
return -1;
} else if (childpid == 0) { /* child */
chdir(dirpath);
if (channels != NULL) {
int fds;
fds = ptys_open(fdm, pts_name);
if (fds < 0) {
fprintf(stderr, "%s(%d): returning due to error: %s\n", __FUNCTION__, __LINE__, strerror(errno));
return -1;
}
/* Close the read end of pipe2 */
if (close(pipe2[0]) == -1)
perror("close(pipe2[0]))");
/* close the master, no need in the child */
close(fdm);
set_noecho(fds);
/* redirections */
dup2(fds, STDIN_FILENO); /* dup stdin */
dup2(fds, STDOUT_FILENO); /* dup stdout */
dup2(pipe2[1], STDERR_FILENO); /* dup stderr */
close(fds); /* done with fds. */
}
/* Close all the fd's in the child */
{
int fdlimit = sysconf(_SC_OPEN_MAX);
int fd = 3;
while (fd < fdlimit)
close(fd++);
}
if (envp[0] == NULL) {
execv(full_path, argv);
} else {
execve(full_path, argv, envp);
}
_exit(127);
} else if (childpid != 0) { /* parent */
set_noecho(fdm);
if (channels != NULL) {
/* close the write end of pipe1 */
if (close(pipe2[1]) == -1)
perror("close(pipe2[1])");
channels[0] = fdm; /* Input Stream. */
channels[1] = fdm; /* Output Stream. */
channels[2] = pipe2[0]; /* stderr Stream. */
/*channels[2] = fdm; Input Stream. */
}
free(full_path);
return childpid;
}
free(full_path);
return -1; /*NOT REACHED */
}
#ifdef __STAND_ALONE__
int main(int argc, char **argv, char **envp) {
const char *path = "./bufferring_test";
int channels[3] = { -1, -1, -1};
int status;
FILE *app_stdin;
FILE *app_stdout;
FILE *app_stderr;
char pts_name[32];
int fdm;
char buffer[32];
fdm = ptym_open(pts_name);
status = exec_pty(path, argv, envp, ".", channels, pts_name, fdm);
if (status >= 0) {
app_stdin = fdopen(channels[0], "w");
app_stdout = fdopen(channels[1], "r");
app_stderr = fdopen(channels[2], "r");
if (app_stdout == NULL || app_stderr == NULL || app_stdin == NULL) {
fprintf(stderr, "PROBLEMS\n");
} else {
fputs("foo\n", app_stdin);
fputs("bar\n", app_stdin);
while(fgets(buffer, sizeof buffer, app_stdout) != NULL) {
fprintf(stdout, "STDOUT: %s\n", buffer);
}
while(fgets(buffer, sizeof buffer, app_stderr) != NULL) {
fprintf(stdout, "STDERR: %s\n", buffer);
}
}
}
fputs("bye\n", stdout);
close(channels[0]);
close(channels[1]);
close(channels[2]);
return 0;
}
#endif
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