xref: /freebsd/contrib/less/lsystem.c (revision 51a9219f5780e61e1437d25220bf8750d9df7f8b)
1 /*
2  * Copyright (C) 1984-2000  Mark Nudelman
3  *
4  * You may distribute under the terms of either the GNU General Public
5  * License or the Less License, as specified in the README file.
6  *
7  * For more information about less, or for information on how to
8  * contact the author, see the README file.
9  */
10 
11 
12 /*
13  * Routines to execute other programs.
14  * Necessarily very OS dependent.
15  */
16 
17 #include "less.h"
18 #include <signal.h>
19 #include "position.h"
20 
21 #if MSDOS_COMPILER
22 #include <dos.h>
23 #ifdef _MSC_VER
24 #include <direct.h>
25 #define setdisk(n) _chdrive((n)+1)
26 #else
27 #include <dir.h>
28 #endif
29 #endif
30 
31 extern int screen_trashed;
32 extern IFILE curr_ifile;
33 
34 
35 #if HAVE_SYSTEM
36 
37 /*
38  * Pass the specified command to a shell to be executed.
39  * Like plain "system()", but handles resetting terminal modes, etc.
40  */
41 	public void
42 lsystem(cmd, donemsg)
43 	char *cmd;
44 	char *donemsg;
45 {
46 	register int inp;
47 #if HAVE_SHELL
48 	register char *shell;
49 	register char *p;
50 #endif
51 	IFILE save_ifile;
52 #if MSDOS_COMPILER
53 	char cwd[FILENAME_MAX+1];
54 #endif
55 
56 	/*
57 	 * Print the command which is to be executed,
58 	 * unless the command starts with a "-".
59 	 */
60 	if (cmd[0] == '-')
61 		cmd++;
62 	else
63 	{
64 		clear_bot();
65 		putstr("!");
66 		putstr(cmd);
67 		putstr("\n");
68 	}
69 
70 #if MSDOS_COMPILER
71 	/*
72 	 * Working directory is global on MSDOS.
73 	 * The child might change the working directory, so we
74 	 * must save and restore CWD across calls to "system",
75 	 * or else we won't find our file when we return and
76 	 * try to "reedit_ifile" it.
77 	 */
78 	getcwd(cwd, FILENAME_MAX);
79 #endif
80 
81 	/*
82 	 * Close the current input file.
83 	 */
84 	save_ifile = save_curr_ifile();
85 	(void) edit_ifile(NULL_IFILE);
86 
87 	/*
88 	 * De-initialize the terminal and take out of raw mode.
89 	 */
90 	deinit();
91 	flush();	/* Make sure the deinit chars get out */
92 	raw_mode(0);
93 #if MSDOS_COMPILER==WIN32C
94 	close_getchr();
95 #endif
96 
97 	/*
98 	 * Restore signals to their defaults.
99 	 */
100 	init_signals(0);
101 
102 #if HAVE_DUP
103 	/*
104 	 * Force standard input to be the user's terminal
105 	 * (the normal standard input), even if less's standard input
106 	 * is coming from a pipe.
107 	 */
108 	inp = dup(0);
109 	close(0);
110 #if OS2
111 	/* The __open() system call translates "/dev/tty" to "con". */
112 	if (__open("/dev/tty", OPEN_READ) < 0)
113 #else
114 	if (open("/dev/tty", OPEN_READ) < 0)
115 #endif
116 		dup(inp);
117 #endif
118 
119 	/*
120 	 * Pass the command to the system to be executed.
121 	 * If we have a SHELL environment variable, use
122 	 * <$SHELL -c "command"> instead of just <command>.
123 	 * If the command is empty, just invoke a shell.
124 	 */
125 #if HAVE_SHELL
126 	p = NULL;
127 	if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
128 	{
129 		if (*cmd == '\0')
130 			p = save(shell);
131 		else
132 		{
133 			char *esccmd;
134 			if ((esccmd = esc_metachars(cmd)) == NULL)
135 			{
136 				p = (char *) ecalloc(strlen(shell) +
137 					strlen(cmd) + 7, sizeof(char));
138 				sprintf(p, "%s -c \"%s\"", shell, cmd);
139 			} else
140 			{
141 				p = (char *) ecalloc(strlen(shell) +
142 					strlen(esccmd) + 5, sizeof(char));
143 				sprintf(p, "%s -c %s", shell, esccmd);
144 				free(esccmd);
145 			}
146 		}
147 	}
148 	if (p == NULL)
149 	{
150 		if (*cmd == '\0')
151 			p = save("sh");
152 		else
153 			p = save(cmd);
154 	}
155 
156 	system(p);
157 	free(p);
158 #else
159 #if MSDOS_COMPILER==DJGPPC
160 	/*
161 	 * Make stdin of the child be in cooked mode.
162 	 */
163 	setmode(0, O_TEXT);
164 	/*
165 	 * We don't need to catch signals of the child (it
166 	 * also makes trouble with some DPMI servers).
167 	 */
168 	__djgpp_exception_toggle();
169   	system(cmd);
170 	__djgpp_exception_toggle();
171 #else
172 	system(cmd);
173 #endif
174 #endif
175 
176 #if HAVE_DUP
177 	/*
178 	 * Restore standard input, reset signals, raw mode, etc.
179 	 */
180 	close(0);
181 	dup(inp);
182 	close(inp);
183 #endif
184 
185 #if MSDOS_COMPILER==WIN32C
186 	open_getchr();
187 #endif
188 	init_signals(1);
189 	raw_mode(1);
190 	if (donemsg != NULL)
191 	{
192 		putstr(donemsg);
193 		putstr("  (press RETURN)");
194 		get_return();
195 		putchr('\n');
196 		flush();
197 	}
198 	init();
199 	screen_trashed = 1;
200 
201 #if MSDOS_COMPILER
202 	/*
203 	 * Restore the previous directory (possibly
204 	 * changed by the child program we just ran).
205 	 */
206 	chdir(cwd);
207 #if MSDOS_COMPILER != DJGPPC
208 	/*
209 	 * Some versions of chdir() don't change to the drive
210 	 * which is part of CWD.  (DJGPP does this in chdir.)
211 	 */
212 	if (cwd[1] == ':')
213 	{
214 		if (cwd[0] >= 'a' && cwd[0] <= 'z')
215 			setdisk(cwd[0] - 'a');
216 		else if (cwd[0] >= 'A' && cwd[0] <= 'Z')
217 			setdisk(cwd[0] - 'A');
218 	}
219 #endif
220 #endif
221 
222 	/*
223 	 * Reopen the current input file.
224 	 */
225 	reedit_ifile(save_ifile);
226 
227 #if defined(SIGWINCH) || defined(SIGWIND)
228 	/*
229 	 * Since we were ignoring window change signals while we executed
230 	 * the system command, we must assume the window changed.
231 	 * Warning: this leaves a signal pending (in "sigs"),
232 	 * so psignals() should be called soon after lsystem().
233 	 */
234 	winch(0);
235 #endif
236 }
237 
238 #endif
239 
240 #if PIPEC
241 
242 /*
243  * Pipe a section of the input file into the given shell command.
244  * The section to be piped is the section "between" the current
245  * position and the position marked by the given letter.
246  *
247  * If the mark is after the current screen, the section between
248  * the top line displayed and the mark is piped.
249  * If the mark is before the current screen, the section between
250  * the mark and the bottom line displayed is piped.
251  * If the mark is on the current screen, or if the mark is ".",
252  * the whole current screen is piped.
253  */
254 	public int
255 pipe_mark(c, cmd)
256 	int c;
257 	char *cmd;
258 {
259 	POSITION mpos, tpos, bpos;
260 
261 	/*
262 	 * mpos = the marked position.
263 	 * tpos = top of screen.
264 	 * bpos = bottom of screen.
265 	 */
266 	mpos = markpos(c);
267 	if (mpos == NULL_POSITION)
268 		return (-1);
269 	tpos = position(TOP);
270 	if (tpos == NULL_POSITION)
271 		tpos = ch_zero();
272 	bpos = position(BOTTOM);
273 
274  	if (c == '.')
275  		return (pipe_data(cmd, tpos, bpos));
276  	else if (mpos <= tpos)
277  		return (pipe_data(cmd, mpos, bpos));
278  	else if (bpos == NULL_POSITION)
279  		return (pipe_data(cmd, tpos, bpos));
280  	else
281  		return (pipe_data(cmd, tpos, mpos));
282 }
283 
284 /*
285  * Create a pipe to the given shell command.
286  * Feed it the file contents between the positions spos and epos.
287  */
288 	public int
289 pipe_data(cmd, spos, epos)
290 	char *cmd;
291 	POSITION spos;
292 	POSITION epos;
293 {
294 	register FILE *f;
295 	register int c;
296 	extern FILE *popen();
297 
298 	/*
299 	 * This is structured much like lsystem().
300 	 * Since we're running a shell program, we must be careful
301 	 * to perform the necessary deinitialization before running
302 	 * the command, and reinitialization after it.
303 	 */
304 	if (ch_seek(spos) != 0)
305 	{
306 		error("Cannot seek to start position", NULL_PARG);
307 		return (-1);
308 	}
309 
310 	if ((f = popen(cmd, "w")) == NULL)
311 	{
312 		error("Cannot create pipe", NULL_PARG);
313 		return (-1);
314 	}
315 	clear_bot();
316 	putstr("!");
317 	putstr(cmd);
318 	putstr("\n");
319 
320 	deinit();
321 	flush();
322 	raw_mode(0);
323 	init_signals(0);
324 #if MSDOS_COMPILER==WIN32C
325 	close_getchr();
326 #endif
327 #ifdef SIGPIPE
328 	LSIGNAL(SIGPIPE, SIG_IGN);
329 #endif
330 
331 	c = EOI;
332 	while (epos == NULL_POSITION || spos++ <= epos)
333 	{
334 		/*
335 		 * Read a character from the file and give it to the pipe.
336 		 */
337 		c = ch_forw_get();
338 		if (c == EOI)
339 			break;
340 		if (putc(c, f) == EOF)
341 			break;
342 	}
343 
344 	/*
345 	 * Finish up the last line.
346 	 */
347  	while (c != '\n' && c != EOI )
348  	{
349  		c = ch_forw_get();
350  		if (c == EOI)
351  			break;
352  		if (putc(c, f) == EOF)
353  			break;
354  	}
355 
356 	pclose(f);
357 
358 #ifdef SIGPIPE
359 	LSIGNAL(SIGPIPE, SIG_DFL);
360 #endif
361 #if MSDOS_COMPILER==WIN32C
362 	open_getchr();
363 #endif
364 	init_signals(1);
365 	raw_mode(1);
366 	init();
367 	screen_trashed = 1;
368 #if defined(SIGWINCH) || defined(SIGWIND)
369 	/* {{ Probably don't need this here. }} */
370 	winch(0);
371 #endif
372 	return (0);
373 }
374 
375 #endif
376 
377 #ifdef _OSK
378 /*
379  *    Popen, and Pclose, for OS-9.
380  *
381  *    Based on code copyright (c) 1988 by Wolfgang Ocker, Puchheim,
382  *                                        Ulli Dessauer, Germering and
383  *                                        Reimer Mellin, Muenchen
384  *                                        (W-Germany)
385  *
386  *    These functions can be copied and distributed freely for any
387  *    non-commercial purposes.  It can only be incorporated into
388  *    commercial software with the written permission of the authors.
389  *
390  *    TOP-specific code stripped out and adapted for less by M.Gregorie, 1996
391  *
392  *    address:    Wolfgang Ocker
393  *                Lochhauserstrasse 35a
394  *                D-8039 Puchheim
395  *                West Germany
396  *
397  *    e-mail:     weo@altger.UUCP, ud@altger.UUCP, ram@altger.UUCP
398  *                pyramid!tmpmbx!recco!weo
399  *                pyramid!tmpmbx!nitmar!ud
400  *                pyramid!tmpmbx!ramsys!ram
401  *
402  *                Martin Gregorie
403  *                10 Sadlers Mead
404  *                Harlow
405  *                Essex, CM18 6HG
406  *                U.K.
407  *
408  *                gregorie@logica.com
409  */
410 #include <strings.h>
411 #include <errno.h>
412 extern char **environ;
413 extern char *getenv();
414 extern int  os9forkc();
415 static int pids[_NFILE] = { 0, 0, 0, 0, 0, 0, 0, 0,
416                             0, 0, 0, 0, 0, 0, 0, 0,
417                             0, 0, 0, 0, 0, 0, 0, 0,
418                             0, 0, 0, 0, 0, 0, 0, 0 };
419 /*
420  * p o p e n
421  */
422 FILE *popen(name, mode)
423 	char *name;
424 	char *mode;
425 {
426     int          fd, fd2, fdsav, pid;
427     static char  *argv[] = {NULL, NULL, NULL };
428     static char  cmd[200];
429     static char  cmd_path[200];
430     char         *cp;
431     char         *shell;
432     FILE         *r;
433     if ((shell = getenv("SHELL")) == NULL)
434         return(NULL);
435     cp = name;
436     while (*cp == ' ')
437         cp++;
438     strcpy(cmd_path, cp);
439     if (cp = index(cmd_path, ' '))
440         *cp++ = '\0';
441     strcpy(cmd, "ex ");
442     strcat(cmd, cmd_path);
443     if (cp)
444     {
445         strcat(cmd, " ");
446         strcat(cmd, cp);
447     }
448     argv[0] = shell;
449     argv[1] = cmd;
450     /*
451          mode is "r" (stdout) or "w" (stdin)
452     */
453     switch(mode[0])
454     {
455         case 'w':   fd = 0;
456                     break;
457         case 'r':   fd = 1;
458                     break;
459         default:    return(NULL);
460     }
461     if (fd == 1)
462         fflush(stdout);
463     fdsav = dup(fd);
464     close(fd);
465 
466     creat("/pipe", S_IWRITE+S_IREAD);
467     pid = os9exec(os9forkc, argv[0], argv, environ, 0, 0, 3);
468     fd2 = dup(fd);
469     close(fd);
470     dup(fdsav);
471     close(fdsav);
472     if (pid > 0)
473     {
474         pids[fd2] = pid;
475         r = fdopen(fd2, mode);
476     }
477     else
478     {
479         close(fd2);
480         r = NULL;
481     }
482     return(r);
483 }
484 
485 /*
486  * p c l o s e
487  */
488 int pclose(fp)
489 	FILE *fp;
490 {
491     unsigned int    status;
492     int             pid;
493     int             fd,
494                     i;
495     fd = fileno(fp);
496     if (pids[fd] == 0)
497         return(-1);
498     fflush(fp);
499     fclose(fp);
500     while ((pid = wait(&status)) != -1)
501         if (pid == pids[fd])
502             break;
503         else
504             for (i = 0; i < _NFILE; i++)
505                 if (pids[i] == pid)
506                 {
507                     pids[i] = 0;
508                     break;
509                 }
510     if (pid == -1)
511         status = -1;
512     pids[fd] = 0;
513     return(status);
514 }
515 #endif /* _OSK */
516