Annotation of src/usr.bin/less/lsystem.c, Revision 1.7
1.1 etheisen 1: /*
1.5 millert 2: * Copyright (C) 1984-2002 Mark Nudelman
1.1 etheisen 3: *
1.5 millert 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.
1.1 etheisen 6: *
1.5 millert 7: * For more information about less, or for information on how to
8: * contact the author, see the README file.
1.1 etheisen 9: */
10:
11:
12: /*
13: * Routines to execute other programs.
14: * Necessarily very OS dependent.
15: */
16:
1.5 millert 17: #include "less.h"
1.1 etheisen 18: #include <signal.h>
19: #include "position.h"
20:
1.5 millert 21: #if MSDOS_COMPILER
1.1 etheisen 22: #include <dos.h>
1.5 millert 23: #ifdef _MSC_VER
24: #include <direct.h>
25: #define setdisk(n) _chdrive((n)+1)
26: #else
27: #include <dir.h>
28: #endif
1.1 etheisen 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
1.5 millert 42: lsystem(cmd, donemsg)
1.1 etheisen 43: char *cmd;
1.5 millert 44: char *donemsg;
1.1 etheisen 45: {
1.5 millert 46: register int inp;
47: #if HAVE_SHELL
48: register char *shell;
49: register char *p;
1.1 etheisen 50: #endif
51: IFILE save_ifile;
1.5 millert 52: #if MSDOS_COMPILER
53: char cwd[FILENAME_MAX+1];
54: #endif
1.1 etheisen 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:
1.5 millert 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:
1.1 etheisen 81: /*
82: * Close the current input file.
83: */
1.5 millert 84: save_ifile = save_curr_ifile();
1.1 etheisen 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);
1.5 millert 93: #if MSDOS_COMPILER==WIN32C
94: close_getchr();
95: #endif
1.1 etheisen 96:
97: /*
98: * Restore signals to their defaults.
99: */
100: init_signals(0);
101:
1.5 millert 102: #if HAVE_DUP
1.1 etheisen 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);
1.5 millert 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
1.1 etheisen 116: dup(inp);
1.5 millert 117: #endif
1.1 etheisen 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;
1.5 millert 127: if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
1.1 etheisen 128: {
129: if (*cmd == '\0')
130: p = save(shell);
131: else
132: {
1.5 millert 133: char *esccmd = shell_quote(cmd);
134: if (esccmd != NULL)
135: {
136: size_t len = strlen(shell) + strlen(esccmd) + 5;
137: p = (char *) ecalloc(len, sizeof(char));
138: snprintf(p, len, "%s %s %s", shell,
139: shell_coption(), esccmd);
140: free(esccmd);
141: }
1.1 etheisen 142: }
143: }
144: if (p == NULL)
145: {
146: if (*cmd == '\0')
147: p = save("sh");
148: else
149: p = save(cmd);
150: }
151: system(p);
152: free(p);
153: #else
1.5 millert 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);
1.1 etheisen 168: #endif
169: #endif
170:
1.5 millert 171: #if HAVE_DUP
1.1 etheisen 172: /*
173: * Restore standard input, reset signals, raw mode, etc.
174: */
175: close(0);
176: dup(inp);
177: close(inp);
1.5 millert 178: #endif
1.1 etheisen 179:
1.5 millert 180: #if MSDOS_COMPILER==WIN32C
181: open_getchr();
182: #endif
1.1 etheisen 183: init_signals(1);
184: raw_mode(1);
1.5 millert 185: if (donemsg != NULL)
186: {
187: putstr(donemsg);
188: putstr(" (press RETURN)");
189: get_return();
190: putchr('\n');
191: flush();
192: }
1.1 etheisen 193: init();
194: screen_trashed = 1;
195:
1.5 millert 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:
1.1 etheisen 217: /*
218: * Reopen the current input file.
219: */
1.5 millert 220: reedit_ifile(save_ifile);
1.1 etheisen 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: *
1.5 millert 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.
1.1 etheisen 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)
1.5 millert 272: return (pipe_data(cmd, mpos, bpos));
1.1 etheisen 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: {
1.5 millert 289: register FILE *f;
290: register int c;
1.1 etheisen 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);
1.5 millert 319: #if MSDOS_COMPILER==WIN32C
320: close_getchr();
321: #endif
1.1 etheisen 322: #ifdef SIGPIPE
1.5 millert 323: LSIGNAL(SIGPIPE, SIG_IGN);
1.1 etheisen 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
1.5 millert 354: LSIGNAL(SIGPIPE, SIG_DFL);
355: #endif
356: #if MSDOS_COMPILER==WIN32C
357: open_getchr();
1.1 etheisen 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
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