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//required for posix_openpt to work
#define _XOPEN_SOURCE 600
#define _DEFAULT_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <termios.h>
//#include <asm/termbits.h>
#include <string.h>
#include <signal.h>
#include "im.h"
int running = 1;
//hook for when the pty child process dies
void childhook(int a) {
running = 0;
}
int pty_slave = -1;
//terminal rows and cols
int trows = 0;
int tcols = 0;
//hook for SIGWINCH
void winchhook(int a) {
struct winsize sz;
ioctl(STDIN_FILENO, TIOCGWINSZ, &sz);
trows = sz.ws_row;
tcols = sz.ws_col;
//trick programs into thinking the terminal is smaller than it is
if (sz.ws_row >= 1) {
sz.ws_row--;
}
ioctl(pty_slave, TIOCSWINSZ, &sz);
}
void disp_im() {
//3 spaces for the im indicator +1 for automargin
int im_col = tcols - IM_TABLE_ENTRY_LEN - 4;
char pos_str[32] = "";
int l = sprintf(pos_str, "\033[%d;%df",trows, im_col);
//printf("\0337");
//printf("\033[%d;%df",trows,im_col);
//printf("\033[0;0f",trows,im_col);
//printf("\033[7m");
//if (im_on) {
// printf("漢");
//} else {
// printf("英");
//}
//printf("%s",im_buffer);
//printf("\033[0m");
//printf("\0338");
write(STDOUT_FILENO,"\0337",2);
//also writes to top left the current im buffer
//write(STDOUT_FILENO,"\033[33;14f",8);
//write(STDOUT_FILENO,"\033[0;4f",6);
//write to the bottom left corner
write(STDOUT_FILENO, pos_str,l);
//invert video
write(STDOUT_FILENO,"\033[7m",4);
//overwrite what was there previously
write(STDOUT_FILENO," ",
IM_TABLE_ENTRY_LEN+4);
write(STDOUT_FILENO, pos_str,l);
//im mode indicator
if (im_on) {
write(STDOUT_FILENO,"漢:",4);
} else {
write(STDOUT_FILENO,"英:",4);
}
//actual buffer
write(STDOUT_FILENO,im_buffer,im_buffer_pos);
//restore cursor pos and attrbutes
write(STDOUT_FILENO,"\033[0m",4);
write(STDOUT_FILENO,"\0338",2);
}
int main (int argc, char * argv[], char * envp[]) {
//creates the pty master
int pty_master = posix_openpt(O_RDWR);
if (pty_master < 0) {
fprintf(stderr, "errno: %d, failed to create pty master", errno);
return errno;
}
//makes it nonblocking
fcntl(pty_master, F_SETFL,O_NONBLOCK);
//make it raw
struct termios stdin_termio;
struct termios stdin_termio_bk;
tcgetattr(STDIN_FILENO,&stdin_termio);
tcgetattr(STDIN_FILENO,&stdin_termio_bk);
cfmakeraw(&stdin_termio);
tcsetattr(STDIN_FILENO,TCSANOW,&stdin_termio);
//make it nonblocking
fcntl(STDIN_FILENO, F_SETFL,O_NONBLOCK);
if ( unlockpt(pty_master) <0) {
fprintf(stderr, "errno: %d, failed to unlock pty slave", errno);
return errno;
}
//gets slave path
char * pty_slave_fn = ptsname(pty_master);
//tries to open pty slave
pty_slave = open(pty_slave_fn, O_RDWR);
if (pty_slave < 0) {
fprintf(stderr, "errno: %d, failed to open pty slave '%s'",\
errno, pty_slave_fn);
return errno;
}
//make the pty slave the same line discipline stdin was
tcsetattr(pty_slave,TCSANOW,&stdin_termio_bk);
//syncs the window sizes for the first time
winchhook(0);
//forks for running bash
pid_t mypid = fork();
if (mypid == 0) {
//set self to be session leader
if (setsid() <0) {
fprintf(stderr, "failed to make new session\n");
}
//all the stand streams
freopen(pty_slave_fn, "r", stdin);
freopen(pty_slave_fn, "w", stdout);
freopen(pty_slave_fn, "w", stderr);
//must be a session leader to set the controlling terminal
if (ioctl(pty_slave, TIOCSCTTY, 0)) {
fprintf(stderr, "errno: %d, failed to set controlling tty\n", errno);
}
/*
* Opens up the Shell now
*/
//opens up the slave pty
//needs to fork
//then set its own process group
//need to set the terminal
//exec bash then
//gets the shell to use, order is
// argument 1, then $SHELL< then /bin/sh
char * shellpath = "/bin/sh";
if (argc >1) {
shellpath = argv[1];
} else if (getenv("SHELL") != NULL) {
shellpath = getenv("SHELL");
}
//gets the terminal environmental variabke, 32 should be enough
char env_term[32] = "TERM=";
strcat(env_term, getenv("TERM"));
char env_home[32] = "HOME=";
strcat(env_home, getenv("HOME"));
char * shell_envs[3] = {env_term,env_home, NULL};
char * shell_args[2] = {shellpath, NULL};
//if (execve(shellpath,shell_args, shell_envs) == -1) {
if (execve(shellpath,shell_args, envp) == -1) {
fprintf(stderr, "errno: %d, Failed to start shell '%s'\n", errno, shellpath);
return errno;
}
//should automatically close any file descriptors
_exit(0);
} else {
signal(SIGCHLD, childhook);
signal(SIGWINCH, winchhook);
char readbuffer[1] = {0};
int chars_read = 0;
//open
while (running) {
//just relay everything for now
//read uses file descriptors and is a system call
chars_read = read(pty_master,readbuffer,1);
if (chars_read >0) {
write(STDOUT_FILENO,readbuffer,1);
}
chars_read = read(STDIN_FILENO, readbuffer, 1);
if (chars_read > 0) {
//write(pty_master,readbuffer,1);
//relays input from stdin
char input_buffer[IM_TABLE_ENTRY_LEN] = {0};
int im_chars = update_im_state(readbuffer[0],
input_buffer);
input_buffer[im_chars] = 0;
if (im_chars >0) {
write(pty_master,input_buffer,im_chars);
}
disp_im();
}
}
}
close(pty_master);
tcsetattr(STDIN_FILENO,TCSANOW,&stdin_termio_bk);
//close(pty_slave);
return 0;
}
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