xref: /freebsd/contrib/less/lsystem.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
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 <signal.h>
18 #include "less.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 (open("/dev/tty", OPEN_READ) < 0)
111 		dup(inp);
112 #endif
113 
114 	/*
115 	 * Pass the command to the system to be executed.
116 	 * If we have a SHELL environment variable, use
117 	 * <$SHELL -c "command"> instead of just <command>.
118 	 * If the command is empty, just invoke a shell.
119 	 */
120 #if HAVE_SHELL
121 	p = NULL;
122 	if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
123 	{
124 		if (*cmd == '\0')
125 			p = save(shell);
126 		else
127 		{
128 			char *esccmd;
129 			if ((esccmd = esc_metachars(cmd)) == NULL)
130 			{
131 				p = (char *) ecalloc(strlen(shell) +
132 					strlen(cmd) + 7, sizeof(char));
133 				sprintf(p, "%s -c \"%s\"", shell, cmd);
134 			} else
135 			{
136 				p = (char *) ecalloc(strlen(shell) +
137 					strlen(esccmd) + 5, sizeof(char));
138 				sprintf(p, "%s -c %s", shell, esccmd);
139 				free(esccmd);
140 			}
141 		}
142 	}
143 	if (p == NULL)
144 	{
145 		if (*cmd == '\0')
146 			p = save("sh");
147 		else
148 			p = save(cmd);
149 	}
150 
151 	system(p);
152 	free(p);
153 #else
154 #if MSDOS_COMPILER==DJGPPC
155 	/*
156 	 * Make stdin of the child be in cooked mode.
157 	 */
158 	setmode(0, O_TEXT);
159 	/*
160 	 * We don't need to catch signals of the child (it
161 	 * also makes trouble with some DPMI servers).
162 	 */
163 	__djgpp_exception_toggle();
164   	system(cmd);
165 	__djgpp_exception_toggle();
166 #else
167 	system(cmd);
168 #endif
169 #endif
170 
171 #if HAVE_DUP
172 	/*
173 	 * Restore standard input, reset signals, raw mode, etc.
174 	 */
175 	close(0);
176 	dup(inp);
177 	close(inp);
178 #endif
179 
180 #if MSDOS_COMPILER==WIN32C
181 	open_getchr();
182 #endif
183 	init_signals(1);
184 	raw_mode(1);
185 	if (donemsg != NULL)
186 	{
187 		putstr(donemsg);
188 		putstr("  (press RETURN)");
189 		get_return();
190 		putchr('\n');
191 		flush();
192 	}
193 	init();
194 	screen_trashed = 1;
195 
196 #if MSDOS_COMPILER
197 	/*
198 	 * Restore the previous directory (possibly
199 	 * changed by the child program we just ran).
200 	 */
201 	chdir(cwd);
202 #if MSDOS_COMPILER != DJGPPC
203 	/*
204 	 * Some versions of chdir() don't change to the drive
205 	 * which is part of CWD.  (DJGPP does this in chdir.)
206 	 */
207 	if (cwd[1] == ':')
208 	{
209 		if (cwd[0] >= 'a' && cwd[0] <= 'z')
210 			setdisk(cwd[0] - 'a');
211 		else if (cwd[0] >= 'A' && cwd[0] <= 'Z')
212 			setdisk(cwd[0] - 'A');
213 	}
214 #endif
215 #endif
216 
217 	/*
218 	 * Reopen the current input file.
219 	 */
220 	reedit_ifile(save_ifile);
221 
222 #if defined(SIGWINCH) || defined(SIGWIND)
223 	/*
224 	 * Since we were ignoring window change signals while we executed
225 	 * the system command, we must assume the window changed.
226 	 * Warning: this leaves a signal pending (in "sigs"),
227 	 * so psignals() should be called soon after lsystem().
228 	 */
229 	winch(0);
230 #endif
231 }
232 
233 #endif
234 
235 #if PIPEC
236 
237 /*
238  * Pipe a section of the input file into the given shell command.
239  * The section to be piped is the section "between" the current
240  * position and the position marked by the given letter.
241  *
242  * If the mark is after the current screen, the section between
243  * the top line displayed and the mark is piped.
244  * If the mark is before the current screen, the section between
245  * the mark and the bottom line displayed is piped.
246  * If the mark is on the current screen, or if the mark is ".",
247  * the whole current screen is piped.
248  */
249 	public int
250 pipe_mark(c, cmd)
251 	int c;
252 	char *cmd;
253 {
254 	POSITION mpos, tpos, bpos;
255 
256 	/*
257 	 * mpos = the marked position.
258 	 * tpos = top of screen.
259 	 * bpos = bottom of screen.
260 	 */
261 	mpos = markpos(c);
262 	if (mpos == NULL_POSITION)
263 		return (-1);
264 	tpos = position(TOP);
265 	if (tpos == NULL_POSITION)
266 		tpos = ch_zero();
267 	bpos = position(BOTTOM);
268 
269  	if (c == '.')
270  		return (pipe_data(cmd, tpos, bpos));
271  	else if (mpos <= tpos)
272  		return (pipe_data(cmd, mpos, bpos));
273  	else if (bpos == NULL_POSITION)
274  		return (pipe_data(cmd, tpos, bpos));
275  	else
276  		return (pipe_data(cmd, tpos, mpos));
277 }
278 
279 /*
280  * Create a pipe to the given shell command.
281  * Feed it the file contents between the positions spos and epos.
282  */
283 	public int
284 pipe_data(cmd, spos, epos)
285 	char *cmd;
286 	POSITION spos;
287 	POSITION epos;
288 {
289 	register FILE *f;
290 	register int c;
291 	extern FILE *popen();
292 
293 	/*
294 	 * This is structured much like lsystem().
295 	 * Since we're running a shell program, we must be careful
296 	 * to perform the necessary deinitialization before running
297 	 * the command, and reinitialization after it.
298 	 */
299 	if (ch_seek(spos) != 0)
300 	{
301 		error("Cannot seek to start position", NULL_PARG);
302 		return (-1);
303 	}
304 
305 	if ((f = popen(cmd, "w")) == NULL)
306 	{
307 		error("Cannot create pipe", NULL_PARG);
308 		return (-1);
309 	}
310 	clear_bot();
311 	putstr("!");
312 	putstr(cmd);
313 	putstr("\n");
314 
315 	deinit();
316 	flush();
317 	raw_mode(0);
318 	init_signals(0);
319 #if MSDOS_COMPILER==WIN32C
320 	close_getchr();
321 #endif
322 #ifdef SIGPIPE
323 	LSIGNAL(SIGPIPE, SIG_IGN);
324 #endif
325 
326 	c = EOI;
327 	while (epos == NULL_POSITION || spos++ <= epos)
328 	{
329 		/*
330 		 * Read a character from the file and give it to the pipe.
331 		 */
332 		c = ch_forw_get();
333 		if (c == EOI)
334 			break;
335 		if (putc(c, f) == EOF)
336 			break;
337 	}
338 
339 	/*
340 	 * Finish up the last line.
341 	 */
342  	while (c != '\n' && c != EOI )
343  	{
344  		c = ch_forw_get();
345  		if (c == EOI)
346  			break;
347  		if (putc(c, f) == EOF)
348  			break;
349  	}
350 
351 	pclose(f);
352 
353 #ifdef SIGPIPE
354 	LSIGNAL(SIGPIPE, SIG_DFL);
355 #endif
356 #if MSDOS_COMPILER==WIN32C
357 	open_getchr();
358 #endif
359 	init_signals(1);
360 	raw_mode(1);
361 	init();
362 	screen_trashed = 1;
363 #if defined(SIGWINCH) || defined(SIGWIND)
364 	/* {{ Probably don't need this here. }} */
365 	winch(0);
366 #endif
367 	return (0);
368 }
369 
370 #endif
371 
372 #ifdef _OSK
373 /*
374  *    Popen, and Pclose, for OS-9.
375  *
376  *    Based on code copyright (c) 1988 by Wolfgang Ocker, Puchheim,
377  *                                        Ulli Dessauer, Germering and
378  *                                        Reimer Mellin, Muenchen
379  *                                        (W-Germany)
380  *
381  *    These functions can be copied and distributed freely for any
382  *    non-commercial purposes.  It can only be incorporated into
383  *    commercial software with the written permission of the authors.
384  *
385  *    TOP-specific code stripped out and adapted for less by M.Gregorie, 1996
386  *
387  *    address:    Wolfgang Ocker
388  *                Lochhauserstrasse 35a
389  *                D-8039 Puchheim
390  *                West Germany
391  *
392  *    e-mail:     weo@altger.UUCP, ud@altger.UUCP, ram@altger.UUCP
393  *                pyramid!tmpmbx!recco!weo
394  *                pyramid!tmpmbx!nitmar!ud
395  *                pyramid!tmpmbx!ramsys!ram
396  *
397  *                Martin Gregorie
398  *                10 Sadlers Mead
399  *                Harlow
400  *                Essex, CM18 6HG
401  *                U.K.
402  *
403  *                gregorie@logica.com
404  */
405 #include <strings.h>
406 #include <errno.h>
407 extern char **environ;
408 extern char *getenv();
409 extern int  os9forkc();
410 static int pids[_NFILE] = { 0, 0, 0, 0, 0, 0, 0, 0,
411                             0, 0, 0, 0, 0, 0, 0, 0,
412                             0, 0, 0, 0, 0, 0, 0, 0,
413                             0, 0, 0, 0, 0, 0, 0, 0 };
414 /*
415  * p o p e n
416  */
417 FILE *popen(name, mode)
418 	char *name;
419 	char *mode;
420 {
421     int          fd, fd2, fdsav, pid;
422     static char  *argv[] = {NULL, NULL, NULL };
423     static char  cmd[200];
424     static char  cmd_path[200];
425     char         *cp;
426     char         *shell;
427     FILE         *r;
428     if ((shell = getenv("SHELL")) == NULL)
429         return(NULL);
430     cp = name;
431     while (*cp == ' ')
432         cp++;
433     strcpy(cmd_path, cp);
434     if (cp = index(cmd_path, ' '))
435         *cp++ = '\0';
436     strcpy(cmd, "ex ");
437     strcat(cmd, cmd_path);
438     if (cp)
439     {
440         strcat(cmd, " ");
441         strcat(cmd, cp);
442     }
443     argv[0] = shell;
444     argv[1] = cmd;
445     /*
446          mode is "r" (stdout) or "w" (stdin)
447     */
448     switch(mode[0])
449     {
450         case 'w':   fd = 0;
451                     break;
452         case 'r':   fd = 1;
453                     break;
454         default:    return(NULL);
455     }
456     if (fd == 1)
457         fflush(stdout);
458     fdsav = dup(fd);
459     close(fd);
460 
461     creat("/pipe", S_IWRITE+S_IREAD);
462     pid = os9exec(os9forkc, argv[0], argv, environ, 0, 0, 3);
463     fd2 = dup(fd);
464     close(fd);
465     dup(fdsav);
466     close(fdsav);
467     if (pid > 0)
468     {
469         pids[fd2] = pid;
470         r = fdopen(fd2, mode);
471     }
472     else
473     {
474         close(fd2);
475         r = NULL;
476     }
477     return(r);
478 }
479 
480 /*
481  * p c l o s e
482  */
483 int pclose(fp)
484 	FILE *fp;
485 {
486     unsigned int    status;
487     int             pid;
488     int             fd,
489                     i;
490     fd = fileno(fp);
491     if (pids[fd] == 0)
492         return(-1);
493     fflush(fp);
494     fclose(fp);
495     while ((pid = wait(&status)) != -1)
496         if (pid == pids[fd])
497             break;
498         else
499             for (i = 0; i < _NFILE; i++)
500                 if (pids[i] == pid)
501                 {
502                     pids[i] = 0;
503                     break;
504                 }
505     if (pid == -1)
506         status = -1;
507     pids[fd] = 0;
508     return(status);
509 }
510 #endif /* _OSK */
511