summaryrefslogtreecommitdiffstats
path: root/contrib/less/lsystem.c
blob: 92286a334dbc7caff99c302cf745300d37eed059 (plain)
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
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
/*
 * Copyright (C) 1984-2000  Mark Nudelman
 *
 * You may distribute under the terms of either the GNU General Public
 * License or the Less License, as specified in the README file.
 *
 * For more information about less, or for information on how to 
 * contact the author, see the README file.
 */


/*
 * Routines to execute other programs.
 * Necessarily very OS dependent.
 */

#include <signal.h>
#include "less.h"
#include "position.h"

#if MSDOS_COMPILER
#include <dos.h>
#ifdef _MSC_VER
#include <direct.h>
#define setdisk(n) _chdrive((n)+1)
#else
#include <dir.h>
#endif
#endif

extern int screen_trashed;
extern IFILE curr_ifile;


#if HAVE_SYSTEM

/*
 * Pass the specified command to a shell to be executed.
 * Like plain "system()", but handles resetting terminal modes, etc.
 */
	public void
lsystem(cmd, donemsg)
	char *cmd;
	char *donemsg;
{
	register int inp;
#if HAVE_SHELL
	register char *shell;
	register char *p;
#endif
	IFILE save_ifile;
#if MSDOS_COMPILER
	char cwd[FILENAME_MAX+1];
#endif

	/*
	 * Print the command which is to be executed,
	 * unless the command starts with a "-".
	 */
	if (cmd[0] == '-')
		cmd++;
	else
	{
		clear_bot();
		putstr("!");
		putstr(cmd);
		putstr("\n");
	}

#if MSDOS_COMPILER
	/*
	 * Working directory is global on MSDOS.
	 * The child might change the working directory, so we
	 * must save and restore CWD across calls to "system",
	 * or else we won't find our file when we return and
	 * try to "reedit_ifile" it.
	 */
	getcwd(cwd, FILENAME_MAX);
#endif

	/*
	 * Close the current input file.
	 */
	save_ifile = save_curr_ifile();
	(void) edit_ifile(NULL_IFILE);

	/*
	 * De-initialize the terminal and take out of raw mode.
	 */
	deinit();
	flush();	/* Make sure the deinit chars get out */
	raw_mode(0);
#if MSDOS_COMPILER==WIN32C
	close_getchr();
#endif

	/*
	 * Restore signals to their defaults.
	 */
	init_signals(0);

#if HAVE_DUP
	/*
	 * Force standard input to be the user's terminal
	 * (the normal standard input), even if less's standard input 
	 * is coming from a pipe.
	 */
	inp = dup(0);
	close(0);
	if (open("/dev/tty", OPEN_READ) < 0)
		dup(inp);
#endif

	/*
	 * Pass the command to the system to be executed.
	 * If we have a SHELL environment variable, use
	 * <$SHELL -c "command"> instead of just <command>.
	 * If the command is empty, just invoke a shell.
	 */
#if HAVE_SHELL
	p = NULL;
	if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
	{
		if (*cmd == '\0')
			p = save(shell);
		else
		{
			char *esccmd;
			if ((esccmd = esc_metachars(cmd)) == NULL)
			{
				p = (char *) ecalloc(strlen(shell) +
					strlen(cmd) + 7, sizeof(char));
				sprintf(p, "%s -c \"%s\"", shell, cmd);
			} else
			{
				p = (char *) ecalloc(strlen(shell) +
					strlen(esccmd) + 5, sizeof(char));
				sprintf(p, "%s -c %s", shell, esccmd);
				free(esccmd);
			}
		}
	}
	if (p == NULL)
	{
		if (*cmd == '\0')
			p = save("sh");
		else
			p = save(cmd);
	}

	system(p);
	free(p);
#else
#if MSDOS_COMPILER==DJGPPC
	/*
	 * Make stdin of the child be in cooked mode.
	 */
	setmode(0, O_TEXT);
	/*
	 * We don't need to catch signals of the child (it
	 * also makes trouble with some DPMI servers).
	 */
	__djgpp_exception_toggle();
  	system(cmd);
	__djgpp_exception_toggle();
#else
	system(cmd);
#endif
#endif

#if HAVE_DUP
	/*
	 * Restore standard input, reset signals, raw mode, etc.
	 */
	close(0);
	dup(inp);
	close(inp);
#endif

#if MSDOS_COMPILER==WIN32C
	open_getchr();
#endif
	init_signals(1);
	raw_mode(1);
	if (donemsg != NULL)
	{
		putstr(donemsg);
		putstr("  (press RETURN)");
		get_return();
		putchr('\n');
		flush();
	}
	init();
	screen_trashed = 1;

#if MSDOS_COMPILER
	/*
	 * Restore the previous directory (possibly
	 * changed by the child program we just ran).
	 */
	chdir(cwd);
#if MSDOS_COMPILER != DJGPPC
	/*
	 * Some versions of chdir() don't change to the drive
	 * which is part of CWD.  (DJGPP does this in chdir.)
	 */
	if (cwd[1] == ':')
	{
		if (cwd[0] >= 'a' && cwd[0] <= 'z')
			setdisk(cwd[0] - 'a');
		else if (cwd[0] >= 'A' && cwd[0] <= 'Z')
			setdisk(cwd[0] - 'A');
	}
#endif
#endif

	/*
	 * Reopen the current input file.
	 */
	reedit_ifile(save_ifile);

#if defined(SIGWINCH) || defined(SIGWIND)
	/*
	 * Since we were ignoring window change signals while we executed
	 * the system command, we must assume the window changed.
	 * Warning: this leaves a signal pending (in "sigs"),
	 * so psignals() should be called soon after lsystem().
	 */
	winch(0);
#endif
}

#endif

#if PIPEC

/*
 * Pipe a section of the input file into the given shell command.
 * The section to be piped is the section "between" the current
 * position and the position marked by the given letter.
 *
 * If the mark is after the current screen, the section between
 * the top line displayed and the mark is piped.
 * If the mark is before the current screen, the section between
 * the mark and the bottom line displayed is piped.
 * If the mark is on the current screen, or if the mark is ".",
 * the whole current screen is piped.
 */
	public int
pipe_mark(c, cmd)
	int c;
	char *cmd;
{
	POSITION mpos, tpos, bpos;

	/*
	 * mpos = the marked position.
	 * tpos = top of screen.
	 * bpos = bottom of screen.
	 */
	mpos = markpos(c);
	if (mpos == NULL_POSITION)
		return (-1);
	tpos = position(TOP);
	if (tpos == NULL_POSITION)
		tpos = ch_zero();
	bpos = position(BOTTOM);

 	if (c == '.') 
 		return (pipe_data(cmd, tpos, bpos));
 	else if (mpos <= tpos)
 		return (pipe_data(cmd, mpos, bpos));
 	else if (bpos == NULL_POSITION)
 		return (pipe_data(cmd, tpos, bpos));
 	else
 		return (pipe_data(cmd, tpos, mpos));
}

/*
 * Create a pipe to the given shell command.
 * Feed it the file contents between the positions spos and epos.
 */
	public int
pipe_data(cmd, spos, epos)
	char *cmd;
	POSITION spos;
	POSITION epos;
{
	register FILE *f;
	register int c;
	extern FILE *popen();

	/*
	 * This is structured much like lsystem().
	 * Since we're running a shell program, we must be careful
	 * to perform the necessary deinitialization before running
	 * the command, and reinitialization after it.
	 */
	if (ch_seek(spos) != 0)
	{
		error("Cannot seek to start position", NULL_PARG);
		return (-1);
	}

	if ((f = popen(cmd, "w")) == NULL)
	{
		error("Cannot create pipe", NULL_PARG);
		return (-1);
	}
	clear_bot();
	putstr("!");
	putstr(cmd);
	putstr("\n");

	deinit();
	flush();
	raw_mode(0);
	init_signals(0);
#if MSDOS_COMPILER==WIN32C
	close_getchr();
#endif
#ifdef SIGPIPE
	LSIGNAL(SIGPIPE, SIG_IGN);
#endif

	c = EOI;
	while (epos == NULL_POSITION || spos++ <= epos)
	{
		/*
		 * Read a character from the file and give it to the pipe.
		 */
		c = ch_forw_get();
		if (c == EOI)
			break;
		if (putc(c, f) == EOF)
			break;
	}

	/*
	 * Finish up the last line.
	 */
 	while (c != '\n' && c != EOI ) 
 	{
 		c = ch_forw_get();
 		if (c == EOI)
 			break;
 		if (putc(c, f) == EOF)
 			break;
 	}

	pclose(f);

#ifdef SIGPIPE
	LSIGNAL(SIGPIPE, SIG_DFL);
#endif
#if MSDOS_COMPILER==WIN32C
	open_getchr();
#endif
	init_signals(1);
	raw_mode(1);
	init();
	screen_trashed = 1;
#if defined(SIGWINCH) || defined(SIGWIND)
	/* {{ Probably don't need this here. }} */
	winch(0);
#endif
	return (0);
}

#endif

#ifdef _OSK
/*
 *    Popen, and Pclose, for OS-9.
 *
 *    Based on code copyright (c) 1988 by Wolfgang Ocker, Puchheim,
 *                                        Ulli Dessauer, Germering and
 *                                        Reimer Mellin, Muenchen
 *                                        (W-Germany)
 *
 *    These functions can be copied and distributed freely for any
 *    non-commercial purposes.  It can only be incorporated into
 *    commercial software with the written permission of the authors.
 *
 *    TOP-specific code stripped out and adapted for less by M.Gregorie, 1996
 *
 *    address:    Wolfgang Ocker
 *                Lochhauserstrasse 35a
 *                D-8039 Puchheim
 *                West Germany
 *
 *    e-mail:     weo@altger.UUCP, ud@altger.UUCP, ram@altger.UUCP
 *                pyramid!tmpmbx!recco!weo
 *                pyramid!tmpmbx!nitmar!ud
 *                pyramid!tmpmbx!ramsys!ram
 *
 *                Martin Gregorie
 *                10 Sadlers Mead
 *                Harlow
 *                Essex, CM18 6HG
 *                U.K.
 *
 *                gregorie@logica.com
 */
#include <strings.h>
#include <errno.h>
extern char **environ;
extern char *getenv();
extern int  os9forkc();
static int pids[_NFILE] = { 0, 0, 0, 0, 0, 0, 0, 0,
                            0, 0, 0, 0, 0, 0, 0, 0,
                            0, 0, 0, 0, 0, 0, 0, 0,
                            0, 0, 0, 0, 0, 0, 0, 0 };
/* 
 * p o p e n
 */
FILE *popen(name, mode)
	char *name;
	char *mode;
{
    int          fd, fd2, fdsav, pid;
    static char  *argv[] = {NULL, NULL, NULL };
    static char  cmd[200];
    static char  cmd_path[200];
    char         *cp;
    char         *shell;
    FILE         *r;
    if ((shell = getenv("SHELL")) == NULL)
        return(NULL);
    cp = name;
    while (*cp == ' ')
        cp++;
    strcpy(cmd_path, cp);
    if (cp = index(cmd_path, ' '))
        *cp++ = '\0';
    strcpy(cmd, "ex ");
    strcat(cmd, cmd_path);
    if (cp)
    {
        strcat(cmd, " ");
        strcat(cmd, cp);
    }
    argv[0] = shell;
    argv[1] = cmd;
    /*
         mode is "r" (stdout) or "w" (stdin)
    */
    switch(mode[0])
    {
        case 'w':   fd = 0;
                    break;
        case 'r':   fd = 1;
                    break;
        default:    return(NULL);
    }
    if (fd == 1)
        fflush(stdout);
    fdsav = dup(fd);
    close(fd);
 
    creat("/pipe", S_IWRITE+S_IREAD);
    pid = os9exec(os9forkc, argv[0], argv, environ, 0, 0, 3);
    fd2 = dup(fd);
    close(fd);
    dup(fdsav);
    close(fdsav);
    if (pid > 0)
    {
        pids[fd2] = pid;
        r = fdopen(fd2, mode);
    }
    else
    {
        close(fd2);
        r = NULL;
    }
    return(r);
}

/*
 * p c l o s e
 */
int pclose(fp)
	FILE *fp;
{
    unsigned int    status;
    int             pid;
    int             fd,
                    i;
    fd = fileno(fp);
    if (pids[fd] == 0)
        return(-1);
    fflush(fp);
    fclose(fp);
    while ((pid = wait(&status)) != -1)
        if (pid == pids[fd])
            break;
        else
            for (i = 0; i < _NFILE; i++)
                if (pids[i] == pid)
                {
                    pids[i] = 0;
                    break;
                }
    if (pid == -1)
        status = -1;
    pids[fd] = 0;
    return(status);
}
#endif /* _OSK */
OpenPOWER on IntegriCloud