st/std.c
Matthias-Christian Ott e2ac1676b1 drop support for proprietary UNIX variants
Proprietary UNIX variants like AIX, HP-UX or SCO UNIX
are nowadays rarely used and maintaining compatibility to
non-standard operating systems interfaces is wasteful and
practically useless.

Projects like xterm suffer from backward compatibility to decades-old
UNIX variants and terminal standards. This does not conform to st's
design goals.
2008-06-02 18:40:22 +02:00

326 lines
5.5 KiB
C

#include <sys/ioctl.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define LENGTH(x) (sizeof (x) / sizeof (x)[0])
#define MAX(a,b) (((a) > (b)) ? (a) : (b))
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
void buffer(char c);
void cmd(const char *cmdstr, ...);
void *emallocz(unsigned int size);
void eprint(const char *errstr, ...);
void eprintn(const char *errstr, ...);
void getpty(void);
void movea(int x, int y);
void mover(int x, int y);
void parse(void);
void scroll(int l);
void shell(void);
void sigchld(int n);
char unbuffer(void);
enum { QuestionMark = 1, Digit = 2 };
typedef struct {
unsigned char data[BUFSIZ];
int s, e;
int n;
} RingBuffer;
int cols = 80, lines = 25;
int cx = 0, cy = 0;
int c, s;
FILE *fptm = NULL;
int ptm, pts;
_Bool bold;
pid_t pid;
RingBuffer buf;
void
buffer(char c) {
if(buf.n < LENGTH(buf.data))
buf.n++;
else
buf.s = (buf.s + 1) % LENGTH(buf.data);
buf.data[buf.e++] = c;
buf.e %= LENGTH(buf.data);
}
void
cmd(const char *cmdstr, ...) {
va_list ap;
putchar('\n');
putchar(':');
va_start(ap, cmdstr);
vfprintf(stdout, cmdstr, ap);
va_end(ap);
}
void *
emallocz(unsigned int size) {
void *res = calloc(1, size);
if(!res)
eprint("fatal: could not malloc() %u bytes\n", size);
return res;
}
void
eprint(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
vfprintf(stderr, errstr, ap);
va_end(ap);
exit(EXIT_FAILURE);
}
void
eprintn(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
vfprintf(stderr, errstr, ap);
va_end(ap);
fprintf(stderr, ": %s\n", strerror(errno));
exit(EXIT_FAILURE);
}
void
getpty(void) {
char *ptsdev;
#if defined(_GNU_SOURCE)
ptm = getpt();
#elif _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600
ptm = posix_openpt(O_RDWR);
#else
ptm = open("/dev/ptmx", O_RDWR);
if(ptm == -1) {
if(openpty(&ptm, &pts, NULL, NULL, NULL) == -1)
eprintn("error, cannot open pty");
return;
}
#endif
#if defined(_XOPEN_SOURCE)
if(ptm != -1) {
if(grantpt(ptm) == -1)
eprintn("error, cannot grant access to pty");
if(unlockpt(ptm) == -1)
eprintn("error, cannot unlock pty");
ptsdev = ptsname(ptm);
if(!ptsdev)
eprintn("error, slave pty name undefined");
pts = open(ptsdev, O_RDWR);
if(pts == -1)
eprintn("error, cannot open slave pty");
puts(ptsdev);
}
else
eprintn("error, cannot open pty");
#endif
}
void
movea(int x, int y) {
x = MAX(x, cols);
y = MAX(y, lines);
cx = x;
cy = y;
cmd("s %d,%d", x, y);
}
void
mover(int x, int y) {
movea(cx + x, cy + y);
}
void
parseesc(void) {
int i, j;
int arg[16];
memset(arg, 0, LENGTH(arg));
s = 0;
c = getc(fptm);
switch(c) {
case '[':
c = getc(fptm);
for(j = 0; j < LENGTH(arg);) {
if(isdigit(c)) {
s |= Digit;
arg[j] *= 10;
arg[j] += c - '0';
}
else if(c == '?')
s |= QuestionMark;
else if(c == ';') {
if(!(s & Digit))
eprint("syntax error");
s &= ~Digit;
j++;
}
else {
if(s & Digit) {
s &= ~Digit;
j++;
}
break;
}
c = getc(fptm);
}
switch(c) {
case '@':
break;
case 'A':
mover(0, j ? arg[0] : 1);
break;
case 'B':
mover(0, j ? -arg[0] : -1);
break;
case 'C':
mover(j ? arg[0] : 1, 0);
break;
case 'D':
mover(j ? -arg[0] : -1, 0);
break;
case 'E':
/* movel(j ? arg[0] : 1); */
break;
case 'F':
/* movel(j ? -arg[0] : -1); */
break;
case '`':
case 'G':
movea(j ? arg[0] : 1, cy);
break;
case 'f':
case 'H':
movea(arg[1] ? arg[1] : 1, arg[0] ? arg[0] : 1);
case 'L':
/* insline(j ? arg[0] : 1); */
break;
case 'M':
/* delline(j ? arg[0] : 1); */
break;
case 'P':
break;
case 'S':
scroll(j ? arg[0] : 1);
break;
case 'T':
scroll(j ? -arg[0] : -1);
break;
case 'd':
movea(cx, j ? arg[0] : 1);
break;
case 'm':
for(i = 0; i < j; i++) {
if(arg[i] >= 30 && arg[i] <= 37)
cmd("#%d", arg[i] - 30);
if(arg[i] >= 40 && arg[i] <= 47)
cmd("|%d", arg[i] - 40);
/* xterm bright colors */
if(arg[i] >= 90 && arg[i] <= 97)
cmd("#%d", arg[i] - 90);
if(arg[i] >= 100 && arg[i] <= 107)
cmd("|%d", arg[i] - 100);
switch(arg[i]) {
case 0:
case 22:
if(bold)
cmd("b");
case 1:
if(!bold)
cmd("b");
break;
}
}
break;
}
break;
default:
putchar('\033');
ungetc(c, fptm);
}
}
void
scroll(int l) {
cmd("s %d, %d", cx, cy + l);
}
void
shell(void) {
static char *shell = NULL;
if(!shell && !(shell = getenv("SHELL")))
shell = "/bin/sh";
pid = fork();
switch(pid) {
case -1:
eprint("error, cannot fork\n");
case 0:
setsid();
dup2(pts, STDIN_FILENO);
dup2(pts, STDOUT_FILENO);
dup2(pts, STDERR_FILENO);
close(ptm);
putenv("TERM=vt102");
execvp(shell, NULL);
break;
default:
close(pts);
signal(SIGCHLD, sigchld);
}
}
void
sigchld(int n) {
int ret;
if(waitpid(pid, &ret, 0) == -1)
eprintn("error, waiting for child failed");
if(WIFEXITED(ret))
exit(WEXITSTATUS(ret));
else
exit(EXIT_SUCCESS);
}
char
unbuffer(void) {
char c;
c = buf.data[buf.s++];
buf.s %= LENGTH(buf.data);
buf.n--;
return c;
}
int
main(int argc, char *argv[]) {
fd_set rd;
if(argc == 2 && !strcmp("-v", argv[1]))
eprint("std-"VERSION", © 2008 Matthias-Christian Ott\n");
else if(argc == 1)
eprint("usage: st [-v]\n");
getpty();
shell();
fdopen(fptm, "r+");
if(!fptm)
eprintn("cannot open slave pty");
return 0;
}