Merge the two `Commentary' sections.
[emacs.git] / src / termcap.c
bloba1c068e0964cfe4a83f133ab68b124673c440c3e
1 /* Work-alike for termcap, plus extra features.
2 Copyright (C) 1985, 86, 93, 94, 95, 2000, 2001
3 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
8 any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; see the file COPYING. If not, write to
17 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
20 /* Emacs config.h may rename various library functions such as malloc. */
21 #ifdef HAVE_CONFIG_H
22 #include <config.h>
23 #endif
25 #ifdef emacs
27 #include <lisp.h> /* xmalloc is here */
28 /* Get the O_* definitions for open et al. */
29 #include <sys/file.h>
30 #ifdef HAVE_FCNTL_H
31 #include <fcntl.h>
32 #endif
33 #ifdef HAVE_UNISTD_H
34 #include <unistd.h>
35 #endif
37 #else /* not emacs */
39 #ifdef STDC_HEADERS
40 #include <stdlib.h>
41 #include <string.h>
42 #else
43 char *getenv ();
44 char *malloc ();
45 char *realloc ();
46 #endif
48 /* Do this after the include, in case string.h prototypes bcopy. */
49 #if (defined(HAVE_STRING_H) || defined(STDC_HEADERS)) && !defined(bcopy)
50 #define bcopy(s, d, n) memcpy ((d), (s), (n))
51 #endif
53 #ifdef HAVE_UNISTD_H
54 #include <unistd.h>
55 #endif
56 #ifdef HAVE_FCNTL_H
57 #include <fcntl.h>
58 #endif
60 #endif /* not emacs */
62 #ifndef NULL
63 #define NULL (char *) 0
64 #endif
66 #ifndef O_RDONLY
67 #define O_RDONLY 0
68 #endif
70 /* BUFSIZE is the initial size allocated for the buffer
71 for reading the termcap file.
72 It is not a limit.
73 Make it large normally for speed.
74 Make it variable when debugging, so can exercise
75 increasing the space dynamically. */
77 #ifndef BUFSIZE
78 #ifdef DEBUG
79 #define BUFSIZE bufsize
81 int bufsize = 128;
82 #else
83 #define BUFSIZE 2048
84 #endif
85 #endif
87 #ifndef TERMCAP_FILE
88 #define TERMCAP_FILE "/etc/termcap"
89 #endif
91 #ifndef emacs
92 static void
93 memory_out ()
95 write (2, "virtual memory exhausted\n", 25);
96 exit (1);
99 static char *
100 xmalloc (size)
101 unsigned size;
103 register char *tem = malloc (size);
105 if (!tem)
106 memory_out ();
107 return tem;
110 static char *
111 xrealloc (ptr, size)
112 char *ptr;
113 unsigned size;
115 register char *tem = realloc (ptr, size);
117 if (!tem)
118 memory_out ();
119 return tem;
121 #endif /* not emacs */
123 /* Looking up capabilities in the entry already found. */
125 /* The pointer to the data made by tgetent is left here
126 for tgetnum, tgetflag and tgetstr to find. */
127 static char *term_entry;
129 static char *tgetst1 ();
131 /* Search entry BP for capability CAP.
132 Return a pointer to the capability (in BP) if found,
133 0 if not found. */
135 static char *
136 find_capability (bp, cap)
137 register char *bp, *cap;
139 for (; *bp; bp++)
140 if (bp[0] == ':'
141 && bp[1] == cap[0]
142 && bp[2] == cap[1])
143 return &bp[4];
144 return NULL;
147 /* These are already defined in the System framework in Mac OS X and
148 cause prebinding to fail. */
149 #ifndef MAC_OSX
151 tgetnum (cap)
152 char *cap;
154 register char *ptr = find_capability (term_entry, cap);
155 if (!ptr || ptr[-1] != '#')
156 return -1;
157 return atoi (ptr);
161 tgetflag (cap)
162 char *cap;
164 register char *ptr = find_capability (term_entry, cap);
165 return ptr && ptr[-1] == ':';
168 /* Look up a string-valued capability CAP.
169 If AREA is non-null, it points to a pointer to a block in which
170 to store the string. That pointer is advanced over the space used.
171 If AREA is null, space is allocated with `malloc'. */
173 char *
174 tgetstr (cap, area)
175 char *cap;
176 char **area;
178 register char *ptr = find_capability (term_entry, cap);
179 if (!ptr || (ptr[-1] != '=' && ptr[-1] != '~'))
180 return NULL;
181 return tgetst1 (ptr, area);
183 #endif /* MAC_OSX */
185 #ifdef IS_EBCDIC_HOST
186 /* Table, indexed by a character in range 0200 to 0300 with 0200 subtracted,
187 gives meaning of character following \, or a space if no special meaning.
188 Sixteen characters per line within the string. */
190 static char esctab[]
191 = " \057\026 \047\014 \
192 \025 \015 \
193 \005 \013 \
195 #else
196 /* Table, indexed by a character in range 0100 to 0140 with 0100 subtracted,
197 gives meaning of character following \, or a space if no special meaning.
198 Eight characters per line within the string. */
200 static char esctab[]
201 = " \007\010 \033\014 \
202 \012 \
203 \015 \011 \013 \
205 #endif
207 /* PTR points to a string value inside a termcap entry.
208 Copy that value, processing \ and ^ abbreviations,
209 into the block that *AREA points to,
210 or to newly allocated storage if AREA is NULL.
211 Return the address to which we copied the value,
212 or NULL if PTR is NULL. */
214 static char *
215 tgetst1 (ptr, area)
216 char *ptr;
217 char **area;
219 register char *p, *r;
220 register int c;
221 register int size;
222 char *ret;
223 register int c1;
225 if (!ptr)
226 return NULL;
228 /* `ret' gets address of where to store the string. */
229 if (!area)
231 /* Compute size of block needed (may overestimate). */
232 p = ptr;
233 while ((c = *p++) && c != ':' && c != '\n')
235 ret = (char *) xmalloc (p - ptr + 1);
237 else
238 ret = *area;
240 /* Copy the string value, stopping at null or colon.
241 Also process ^ and \ abbreviations. */
242 p = ptr;
243 r = ret;
244 while ((c = *p++) && c != ':' && c != '\n')
246 if (c == '^')
248 c = *p++;
249 if (c == '?')
250 c = 0177;
251 else
252 c &= 037;
254 else if (c == '\\')
256 c = *p++;
257 if (c >= '0' && c <= '7')
259 c -= '0';
260 size = 0;
262 while (++size < 3 && (c1 = *p) >= '0' && c1 <= '7')
264 c *= 8;
265 c += c1 - '0';
266 p++;
269 #ifdef IS_EBCDIC_HOST
270 else if (c >= 0200 && c < 0360)
272 c1 = esctab[(c & ~0100) - 0200];
273 if (c1 != ' ')
274 c = c1;
276 #else
277 else if (c >= 0100 && c < 0200)
279 c1 = esctab[(c & ~040) - 0100];
280 if (c1 != ' ')
281 c = c1;
283 #endif
285 *r++ = c;
288 /* Sometimes entries have "%pN" which means use parameter N in the
289 next %-substitution. If all such N are continuous in the range
290 [1,9] we can remove each "%pN" because they are redundant, thus
291 reducing bandwidth requirements. True, Emacs is well beyond the
292 days of 150baud teletypes, but some of its users aren't much so.
294 This pass could probably be integrated into the one above but
295 abbreviation expansion makes that effort a little more hairy than
296 its worth; this is cleaner. */
298 register int last_p_param = 0;
299 int remove_p_params = 1;
300 struct { char *beg; int len; } cut[11];
302 for (cut[0].beg = p = ret; p < r - 3; p++)
304 if (!remove_p_params)
305 break;
306 if (*p == '%' && *(p + 1) == 'p')
308 if (*(p + 2) - '0' == 1 + last_p_param)
310 cut[last_p_param].len = p - cut[last_p_param].beg;
311 last_p_param++;
312 p += 3;
313 cut[last_p_param].beg = p;
315 else /* not continuous: bail */
316 remove_p_params = 0;
317 if (last_p_param > 10) /* too many: bail */
318 remove_p_params = 0;
321 if (remove_p_params && last_p_param)
323 register int i;
324 char *wp;
326 cut[last_p_param].len = r - cut[last_p_param].beg;
327 for (i = 0, wp = ret; i <= last_p_param; wp += cut[i++].len)
328 bcopy (cut[i].beg, wp, cut[i].len);
329 r = wp;
333 *r = '\0';
334 /* Update *AREA. */
335 if (area)
336 *area = r + 1;
337 return ret;
340 /* Outputting a string with padding. */
342 #ifndef emacs
343 short ospeed;
344 /* If OSPEED is 0, we use this as the actual baud rate. */
345 int tputs_baud_rate;
346 #endif
348 /* Already defined in the System framework in Mac OS X and causes
349 prebinding to fail. */
350 #ifndef MAC_OSX
351 char PC;
352 #endif /* MAC_OSX */
354 #ifndef emacs
355 /* Actual baud rate if positive;
356 - baud rate / 100 if negative. */
358 static int speeds[] =
360 #ifdef VMS
361 0, 50, 75, 110, 134, 150, -3, -6, -12, -18,
362 -20, -24, -36, -48, -72, -96, -192
363 #else /* not VMS */
364 0, 50, 75, 110, 135, 150, -2, -3, -6, -12,
365 -18, -24, -48, -96, -192, -288, -384, -576, -1152
366 #endif /* not VMS */
369 #endif /* not emacs */
371 /* Already defined in the System framework in Mac OS X and causes
372 prebinding to fail. */
373 #ifndef MAC_OSX
374 void
375 tputs (str, nlines, outfun)
376 register char *str;
377 int nlines;
378 register int (*outfun) ();
380 register int padcount = 0;
381 register int speed;
383 #ifdef emacs
384 extern EMACS_INT baud_rate;
385 speed = baud_rate;
386 /* For quite high speeds, convert to the smaller
387 units to avoid overflow. */
388 if (speed > 10000)
389 speed = - speed / 100;
390 #else
391 if (ospeed == 0)
392 speed = tputs_baud_rate;
393 else
394 speed = speeds[ospeed];
395 #endif
397 if (!str)
398 return;
400 while (*str >= '0' && *str <= '9')
402 padcount += *str++ - '0';
403 padcount *= 10;
405 if (*str == '.')
407 str++;
408 padcount += *str++ - '0';
410 if (*str == '*')
412 str++;
413 padcount *= nlines;
415 while (*str)
416 (*outfun) (*str++);
418 /* PADCOUNT is now in units of tenths of msec.
419 SPEED is measured in characters per 10 seconds
420 or in characters per .1 seconds (if negative).
421 We use the smaller units for larger speeds to avoid overflow. */
422 padcount *= speed;
423 padcount += 500;
424 padcount /= 1000;
425 if (speed < 0)
426 padcount = -padcount;
427 else
429 padcount += 50;
430 padcount /= 100;
433 while (padcount-- > 0)
434 (*outfun) (PC);
436 #endif /* MAC_OSX */
438 /* Finding the termcap entry in the termcap data base. */
440 struct termcap_buffer
442 char *beg;
443 int size;
444 char *ptr;
445 int ateof;
446 int full;
449 /* Forward declarations of static functions. */
451 static int scan_file ();
452 static char *gobble_line ();
453 static int compare_contin ();
454 static int name_match ();
456 #ifdef VMS
458 #include <rmsdef.h>
459 #include <fab.h>
460 #include <nam.h>
462 static int
463 valid_filename_p (fn)
464 char *fn;
466 struct FAB fab = cc$rms_fab;
467 struct NAM nam = cc$rms_nam;
468 char esa[NAM$C_MAXRSS];
470 fab.fab$l_fna = fn;
471 fab.fab$b_fns = strlen(fn);
472 fab.fab$l_nam = &nam;
473 fab.fab$l_fop = FAB$M_NAM;
475 nam.nam$l_esa = esa;
476 nam.nam$b_ess = sizeof esa;
478 return SYS$PARSE(&fab, 0, 0) == RMS$_NORMAL;
481 #else /* !VMS */
483 #ifdef MSDOS /* MW, May 1993 */
484 static int
485 valid_filename_p (fn)
486 char *fn;
488 return *fn == '/' || fn[1] == ':';
490 #else
491 #define valid_filename_p(fn) (*(fn) == '/')
492 #endif
494 #endif /* !VMS */
496 /* Find the termcap entry data for terminal type NAME
497 and store it in the block that BP points to.
498 Record its address for future use.
500 If BP is null, space is dynamically allocated.
502 Return -1 if there is some difficulty accessing the data base
503 of terminal types,
504 0 if the data base is accessible but the type NAME is not defined
505 in it, and some other value otherwise. */
507 /* Already defined in the System framework in Mac OS X and causes
508 prebinding to fail. */
509 #ifndef MAC_OSX
511 tgetent (bp, name)
512 char *bp, *name;
514 register char *termcap_name;
515 register int fd;
516 struct termcap_buffer buf;
517 register char *bp1;
518 char *tc_search_point;
519 char *term;
520 int malloc_size = 0;
521 register int c;
522 char *tcenv = NULL; /* TERMCAP value, if it contains :tc=. */
523 char *indirect = NULL; /* Terminal type in :tc= in TERMCAP value. */
524 int filep;
526 #ifdef INTERNAL_TERMINAL
527 /* For the internal terminal we don't want to read any termcap file,
528 so fake it. */
529 if (!strcmp (name, "internal"))
531 term = INTERNAL_TERMINAL;
532 if (!bp)
534 malloc_size = 1 + strlen (term);
535 bp = (char *) xmalloc (malloc_size);
537 strcpy (bp, term);
538 goto ret;
540 #endif /* INTERNAL_TERMINAL */
542 /* For compatibility with programs like `less' that want to
543 put data in the termcap buffer themselves as a fallback. */
544 if (bp)
545 term_entry = bp;
547 termcap_name = getenv ("TERMCAP");
548 if (termcap_name && *termcap_name == '\0')
549 termcap_name = NULL;
550 #if defined (MSDOS) && !defined (TEST)
551 if (termcap_name && (*termcap_name == '\\'
552 || *termcap_name == '/'
553 || termcap_name[1] == ':'))
554 dostounix_filename(termcap_name);
555 #endif
557 filep = termcap_name && valid_filename_p (termcap_name);
559 /* If termcap_name is non-null and starts with / (in the un*x case, that is),
560 it is a file name to use instead of /etc/termcap.
561 If it is non-null and does not start with /,
562 it is the entry itself, but only if
563 the name the caller requested matches the TERM variable. */
565 if (termcap_name && !filep && !strcmp (name, getenv ("TERM")))
567 indirect = tgetst1 (find_capability (termcap_name, "tc"), (char **) 0);
568 if (!indirect)
570 if (!bp)
571 bp = termcap_name;
572 else
573 strcpy (bp, termcap_name);
574 goto ret;
576 else
577 { /* It has tc=. Need to read /etc/termcap. */
578 tcenv = termcap_name;
579 termcap_name = NULL;
583 if (!termcap_name || !filep)
584 termcap_name = TERMCAP_FILE;
586 /* Here we know we must search a file and termcap_name has its name. */
588 #ifdef MSDOS
589 fd = open (termcap_name, O_RDONLY|O_TEXT, 0);
590 #else
591 fd = open (termcap_name, O_RDONLY, 0);
592 #endif
593 if (fd < 0)
594 return -1;
596 buf.size = BUFSIZE;
597 /* Add 1 to size to ensure room for terminating null. */
598 buf.beg = (char *) xmalloc (buf.size + 1);
599 term = indirect ? indirect : name;
601 if (!bp)
603 malloc_size = indirect ? strlen (tcenv) + 1 : buf.size;
604 bp = (char *) xmalloc (malloc_size);
606 tc_search_point = bp1 = bp;
608 if (indirect)
609 /* Copy the data from the environment variable. */
611 strcpy (bp, tcenv);
612 bp1 += strlen (tcenv);
615 while (term)
617 /* Scan the file, reading it via buf, till find start of main entry. */
618 if (scan_file (term, fd, &buf) == 0)
620 close (fd);
621 free (buf.beg);
622 if (malloc_size)
623 free (bp);
624 return 0;
627 /* Free old `term' if appropriate. */
628 if (term != name)
629 free (term);
631 /* If BP is malloc'd by us, make sure it is big enough. */
632 if (malloc_size)
634 int offset1 = bp1 - bp, offset2 = tc_search_point - bp;
635 malloc_size = offset1 + buf.size;
636 bp = termcap_name = (char *) xrealloc (bp, malloc_size);
637 bp1 = termcap_name + offset1;
638 tc_search_point = termcap_name + offset2;
641 /* Copy the line of the entry from buf into bp. */
642 termcap_name = buf.ptr;
643 while ((*bp1++ = c = *termcap_name++) && c != '\n')
644 /* Drop out any \ newline sequence. */
645 if (c == '\\' && *termcap_name == '\n')
647 bp1--;
648 termcap_name++;
650 *bp1 = '\0';
652 /* Does this entry refer to another terminal type's entry?
653 If something is found, copy it into heap and null-terminate it. */
654 tc_search_point = find_capability (tc_search_point, "tc");
655 term = tgetst1 (tc_search_point, (char **) 0);
658 close (fd);
659 free (buf.beg);
661 if (malloc_size)
662 bp = (char *) xrealloc (bp, bp1 - bp + 1);
664 ret:
665 term_entry = bp;
666 return 1;
668 #endif /* MAC_OSX */
670 /* Given file open on FD and buffer BUFP,
671 scan the file from the beginning until a line is found
672 that starts the entry for terminal type STR.
673 Return 1 if successful, with that line in BUFP,
674 or 0 if no entry is found in the file. */
676 static int
677 scan_file (str, fd, bufp)
678 char *str;
679 int fd;
680 register struct termcap_buffer *bufp;
682 register char *end;
684 bufp->ptr = bufp->beg;
685 bufp->full = 0;
686 bufp->ateof = 0;
687 *bufp->ptr = '\0';
689 lseek (fd, 0L, 0);
691 while (!bufp->ateof)
693 /* Read a line into the buffer. */
694 end = NULL;
697 /* if it is continued, append another line to it,
698 until a non-continued line ends. */
699 end = gobble_line (fd, bufp, end);
701 while (!bufp->ateof && end[-2] == '\\');
703 if (*bufp->ptr != '#'
704 && name_match (bufp->ptr, str))
705 return 1;
707 /* Discard the line just processed. */
708 bufp->ptr = end;
710 return 0;
713 /* Return nonzero if NAME is one of the names specified
714 by termcap entry LINE. */
716 static int
717 name_match (line, name)
718 char *line, *name;
720 register char *tem;
722 if (!compare_contin (line, name))
723 return 1;
724 /* This line starts an entry. Is it the right one? */
725 for (tem = line; *tem && *tem != '\n' && *tem != ':'; tem++)
726 if (*tem == '|' && !compare_contin (tem + 1, name))
727 return 1;
729 return 0;
732 static int
733 compare_contin (str1, str2)
734 register char *str1, *str2;
736 register int c1, c2;
737 while (1)
739 c1 = *str1++;
740 c2 = *str2++;
741 while (c1 == '\\' && *str1 == '\n')
743 str1++;
744 while ((c1 = *str1++) == ' ' || c1 == '\t');
746 if (c2 == '\0')
748 /* End of type being looked up. */
749 if (c1 == '|' || c1 == ':')
750 /* If end of name in data base, we win. */
751 return 0;
752 else
753 return 1;
755 else if (c1 != c2)
756 return 1;
760 /* Make sure that the buffer <- BUFP contains a full line
761 of the file open on FD, starting at the place BUFP->ptr
762 points to. Can read more of the file, discard stuff before
763 BUFP->ptr, or make the buffer bigger.
765 Return the pointer to after the newline ending the line,
766 or to the end of the file, if there is no newline to end it.
768 Can also merge on continuation lines. If APPEND_END is
769 non-null, it points past the newline of a line that is
770 continued; we add another line onto it and regard the whole
771 thing as one line. The caller decides when a line is continued. */
773 static char *
774 gobble_line (fd, bufp, append_end)
775 int fd;
776 register struct termcap_buffer *bufp;
777 char *append_end;
779 register char *end;
780 register int nread;
781 register char *buf = bufp->beg;
782 register char *tem;
784 if (!append_end)
785 append_end = bufp->ptr;
787 while (1)
789 end = append_end;
790 while (*end && *end != '\n') end++;
791 if (*end)
792 break;
793 if (bufp->ateof)
794 return buf + bufp->full;
795 if (bufp->ptr == buf)
797 if (bufp->full == bufp->size)
799 bufp->size *= 2;
800 /* Add 1 to size to ensure room for terminating null. */
801 tem = (char *) xrealloc (buf, bufp->size + 1);
802 bufp->ptr = (bufp->ptr - buf) + tem;
803 append_end = (append_end - buf) + tem;
804 bufp->beg = buf = tem;
807 else
809 append_end -= bufp->ptr - buf;
810 bcopy (bufp->ptr, buf, bufp->full -= bufp->ptr - buf);
811 bufp->ptr = buf;
813 if (!(nread = read (fd, buf + bufp->full, bufp->size - bufp->full)))
814 bufp->ateof = 1;
815 bufp->full += nread;
816 buf[bufp->full] = '\0';
818 return end + 1;
821 #ifdef TEST
823 #ifdef NULL
824 #undef NULL
825 #endif
827 #include <stdio.h>
829 main (argc, argv)
830 int argc;
831 char **argv;
833 char *term;
834 char *buf;
836 term = argv[1];
837 printf ("TERM: %s\n", term);
839 buf = (char *) tgetent (0, term);
840 if ((int) buf <= 0)
842 printf ("No entry.\n");
843 return 0;
846 printf ("Entry: %s\n", buf);
848 tprint ("cm");
849 tprint ("AL");
851 printf ("co: %d\n", tgetnum ("co"));
852 printf ("am: %d\n", tgetflag ("am"));
855 tprint (cap)
856 char *cap;
858 char *x = tgetstr (cap, 0);
859 register char *y;
861 printf ("%s: ", cap);
862 if (x)
864 for (y = x; *y; y++)
865 if (*y <= ' ' || *y == 0177)
866 printf ("\\%0o", *y);
867 else
868 putchar (*y);
869 free (x);
871 else
872 printf ("none");
873 putchar ('\n');
876 #endif /* TEST */
878 /* arch-tag: c2e8d427-2271-4fac-95fe-411857238b80
879 (do not change this comment) */