static int execute_stream_redirection(const struct conf_t* conf_info)
{
if(redirect_stream(conf_info->file_in,STDIN_FILENO,READ_FLAG) == -1
||redirect_stream(conf_info->file_out,STDOUT_FILENO,WRITE_FLAG) == -1
||redirect_stream(conf_info->file_err,STDERR_FILENO,WRITE_FLAG) == -1)
{
return RET_ERR;
}
return RET_OK;
}
/**
* Pipe: TODO
*/
static int do_pipe(CommandNode *node)
{
int pipefd[2];
if (pipe(pipefd) == 0)
{
int readfd = pipefd[0];
int writefd = pipefd[1];
pid_t source_pid;
pid_t target_pid;
if (((source_pid = fork())) == 0)
{
/* source child */
int retval;
close(readfd);
redirect_stream(writefd, STDOUT_FILENO);
retval = execute(node->op1);
close(writefd);
exit(retval);
}
else
{
/* parent */
close(writefd);
if (((target_pid = fork())) == 0)
{
/* target child */
int retval;
redirect_stream(readfd, STDIN_FILENO);
retval = execute(node->op2);
close(readfd);
exit(retval);
}
else
{
/* parent */
close(readfd);
check_wait(source_pid);
return check_wait(target_pid);
}
}
}
else
{
perror("do_pipe");
return 1;
}
}
/**
* Redirect stdin/stdout to corresponding files
*/
static void redirect_to_files(const char *input, const char *output, int do_output_append)
{
if (input != NULL)
{
int fd = open(input, O_RDONLY);
if (fd < 0)
perror("Cannot open input file");
else
redirect_stream(fd, STDIN_FILENO);
}
if (output != NULL)
{
int fd = open(output, O_WRONLY | O_CREAT | (do_output_append? O_APPEND : O_TRUNC), 0666);
if (fd < 0)
perror("Cannot open output file");
else
redirect_stream(fd, STDOUT_FILENO);
}
}
