1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
|
/* See LICENSE file for copyright and license details. */
#include "util.h"
#include <sys/types.h>
#include <sys/wait.h>
#include <ctype.h>
#include <err.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))
static void buffer(char c);
static void cmd(const char *cmdstr, ...);
static int getch();
void getpty(void);
static void movea(int x, int y);
static void mover(int x, int y);
static void parseesc(void);
static void scroll(int l);
static void shell(void);
static void sigchld(int n);
static char unbuffer(void);
static void ungetch(int c);
typedef struct {
unsigned char data[BUFSIZ];
int s, e;
int n;
} RingBuffer;
typedef struct {
unsigned char data[BUFSIZ];
int i, n;
} ReadBuffer;
static int cols = 80, lines = 25;
static int cx = 0, cy = 0;
static int c;
int ptm, pts;
static _Bool bold, digit, qmark;
static pid_t pid;
static RingBuffer buf;
static ReadBuffer rbuf;
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);
}
int
getch() {
if(rbuf.i++ >= rbuf.n) {
rbuf.n = read(ptm, rbuf.data, LENGTH(rbuf.data));
if(rbuf.n == -1)
err(EXIT_FAILURE, "cannot read from slave pty");
rbuf.i = 0;
}
return rbuf.data[rbuf.i];
}
void
movea(int x, int y) {
x = MAX(x, cols);
y = MAX(y, lines);
cx = x;
cy = y;
cmd("seek(%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));
c = getch();
switch(c) {
case '[':
c = getch();
for(j = 0; j < LENGTH(arg);) {
if(isdigit(c)) {
digit = 1;
arg[j] *= 10;
arg[j] += c - '0';
}
else if(c == '?')
qmark = 1;
else if(c == ';') {
if(!digit)
errx(EXIT_FAILURE, "syntax error");
digit = 0;
j++;
}
else {
if(digit) {
digit = 0;
j++;
}
break;
}
c = getch();
}
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("bold");
case 1:
if(!bold)
cmd("bold");
break;
}
}
break;
}
break;
default:
putchar('\033');
ungetch(c);
}
}
void
scroll(int l) {
cmd("seek(%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:
err(EXIT_FAILURE, "cannot fork");
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)
err(EXIT_FAILURE, "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;
}
void
ungetch(int c) {
if(rbuf.i + 1 >= rbuf.n)
errx(EXIT_FAILURE, "read buffer full");
rbuf.data[rbuf.i++] = c;
}
int
main(int argc, char *argv[]) {
fd_set rfds;
int r;
if(argc == 2 && !strcmp("-v", argv[1])) {
fprintf(stderr, "std-"VERSION", © 2008 Matthias-Christian Ott\n");
exit(EXIT_SUCCESS);
}
else if(argc == 1) {
fprintf(stderr, "usage: st [-v]\n");
exit(EXIT_FAILURE);
}
getpty();
shell();
FD_ZERO(&rfds);
FD_SET(STDIN_FILENO, &rfds);
FD_SET(ptm, &rfds);
for(;;) {
r = select(ptm + 1, &rfds, NULL, NULL, NULL);
if(r == -1)
err(EXIT_FAILURE, "cannot select");
if(FD_ISSET(ptm, &rfds)) {
do {
c = getch();
switch(c) {
case '\033':
parseesc();
break;
default:
putchar(c);
}
} while(rbuf.i < rbuf.n);
fflush(stdout);
}
}
return 0;
}
|
