1 /* $NetBSD: lsystem.c,v 1.4 2013/09/04 19:44:21 tron Exp $ */
2
3 /*
4 * Copyright (C) 1984-2012 Mark Nudelman
5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Less License, as specified in the README file.
8 *
9 * For more information, see the README file.
10 */
11
12
13 /*
14 * Routines to execute other programs.
15 * Necessarily very OS dependent.
16 */
17
18 #include "less.h"
19 #include <signal.h>
20 #include "position.h"
21
22 #if MSDOS_COMPILER
23 #include <dos.h>
24 #ifdef _MSC_VER
25 #include <direct.h>
26 #define setdisk(n) _chdrive((n)+1)
27 #else
28 #include <dir.h>
29 #endif
30 #endif
31
32 extern int screen_trashed;
33 extern IFILE curr_ifile;
34
35
36 #if HAVE_SYSTEM
37
38 /*
39 * Pass the specified command to a shell to be executed.
40 * Like plain "system()", but handles resetting terminal modes, etc.
41 */
42 public void
lsystem(cmd,donemsg)43 lsystem(cmd, donemsg)
44 char *cmd;
45 char *donemsg;
46 {
47 register int inp;
48 #if HAVE_SHELL
49 register char *shell;
50 register char *p;
51 #endif
52 IFILE save_ifile;
53 #if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C
54 char cwd[FILENAME_MAX+1];
55 #endif
56
57 /*
58 * Print the command which is to be executed,
59 * unless the command starts with a "-".
60 */
61 if (cmd[0] == '-')
62 cmd++;
63 else
64 {
65 clear_bot();
66 putstr("!");
67 putstr(cmd);
68 putstr("\n");
69 }
70
71 #if MSDOS_COMPILER
72 #if MSDOS_COMPILER==WIN32C
73 if (*cmd == '\0')
74 cmd = getenv("COMSPEC");
75 #else
76 /*
77 * Working directory is global on MSDOS.
78 * The child might change the working directory, so we
79 * must save and restore CWD across calls to "system",
80 * or else we won't find our file when we return and
81 * try to "reedit_ifile" it.
82 */
83 getcwd(cwd, FILENAME_MAX);
84 #endif
85 #endif
86
87 /*
88 * Close the current input file.
89 */
90 save_ifile = save_curr_ifile();
91 (void) edit_ifile(NULL_IFILE);
92
93 /*
94 * De-initialize the terminal and take out of raw mode.
95 */
96 deinit();
97 flush(); /* Make sure the deinit chars get out */
98 raw_mode(0);
99 #if MSDOS_COMPILER==WIN32C
100 close_getchr();
101 #endif
102
103 /*
104 * Restore signals to their defaults.
105 */
106 init_signals(0);
107
108 #if HAVE_DUP
109 /*
110 * Force standard input to be the user's terminal
111 * (the normal standard input), even if less's standard input
112 * is coming from a pipe.
113 */
114 inp = dup(0);
115 close(0);
116 #if OS2
117 /* The __open() system call translates "/dev/tty" to "con". */
118 if (__open("/dev/tty", OPEN_READ) < 0)
119 #else
120 if (open("/dev/tty", OPEN_READ) < 0)
121 #endif
122 dup(inp);
123 #endif
124
125 /*
126 * Pass the command to the system to be executed.
127 * If we have a SHELL environment variable, use
128 * <$SHELL -c "command"> instead of just <command>.
129 * If the command is empty, just invoke a shell.
130 */
131 #if HAVE_SHELL
132 p = NULL;
133 if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
134 {
135 if (*cmd == '\0')
136 p = save(shell);
137 else
138 {
139 char *esccmd = shell_quote(cmd);
140 if (esccmd != NULL)
141 {
142 int len = strlen(shell) + strlen(esccmd) + 5;
143 p = (char *) ecalloc(len, sizeof(char));
144 SNPRINTF3(p, len, "%s %s %s", shell, shell_coption(), esccmd);
145 free(esccmd);
146 }
147 }
148 }
149 if (p == NULL)
150 {
151 if (*cmd == '\0')
152 p = save("sh");
153 else
154 p = save(cmd);
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 && MSDOS_COMPILER!=WIN32C
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
pipe_mark(c,cmd)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
pipe_data(cmd,spos,epos)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
297 /*
298 * This is structured much like lsystem().
299 * Since we're running a shell program, we must be careful
300 * to perform the necessary deinitialization before running
301 * the command, and reinitialization after it.
302 */
303 if (ch_seek(spos) != 0)
304 {
305 error("Cannot seek to start position", NULL_PARG);
306 return (-1);
307 }
308
309 if ((f = popen(cmd, "w")) == NULL)
310 {
311 error("Cannot create pipe", NULL_PARG);
312 return (-1);
313 }
314 clear_bot();
315 putstr("!");
316 putstr(cmd);
317 putstr("\n");
318
319 deinit();
320 flush();
321 raw_mode(0);
322 init_signals(0);
323 #if MSDOS_COMPILER==WIN32C
324 close_getchr();
325 #endif
326 #ifdef SIGPIPE
327 LSIGNAL(SIGPIPE, SIG_IGN);
328 #endif
329
330 c = EOI;
331 while (epos == NULL_POSITION || spos++ <= epos)
332 {
333 /*
334 * Read a character from the file and give it to the pipe.
335 */
336 c = ch_forw_get();
337 if (c == EOI)
338 break;
339 if (putc(c, f) == EOF)
340 break;
341 }
342
343 /*
344 * Finish up the last line.
345 */
346 while (c != '\n' && c != EOI )
347 {
348 c = ch_forw_get();
349 if (c == EOI)
350 break;
351 if (putc(c, f) == EOF)
352 break;
353 }
354
355 pclose(f);
356
357 #ifdef SIGPIPE
358 LSIGNAL(SIGPIPE, SIG_DFL);
359 #endif
360 #if MSDOS_COMPILER==WIN32C
361 open_getchr();
362 #endif
363 init_signals(1);
364 raw_mode(1);
365 init();
366 screen_trashed = 1;
367 #if defined(SIGWINCH) || defined(SIGWIND)
368 /* {{ Probably don't need this here. }} */
369 winch(0);
370 #endif
371 return (0);
372 }
373
374 #endif
375