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1.1 root 1: /* Copyright (c) 1979 Regents of the University of California */
2: #define BUFSIZ 1024
3: #define MAXHOP 32 /* max number of tc= indirections */
4:
5: #include <ctype.h>
6: #include "local/uparm.h"
7: /*
8: * termcap - routines for dealing with the terminal capability data base
9: *
10: * BUG: Should use a "last" pointer in tbuf, so that searching
11: * for capabilities alphabetically would not be a n**2/2
12: * process when large numbers of capabilities are given.
13: * Note: If we add a last pointer now we will screw up the
14: * tc capability. We really should compile termcap.
15: *
16: * Essentially all the work here is scanning and decoding escapes
17: * in string capabilities. We don't use stdio because the editor
18: * doesn't, and because living w/o it is not hard.
19: */
20:
21: static char *tbuf;
22: static int hopcount; /* detect infinite loops in termcap, init 0 */
23: char *tskip();
24: char *tgetstr();
25: char *tdecode();
26: char *getenv();
27:
28: /*
29: * Get an entry for terminal name in buffer bp,
30: * from the termcap file. Parse is very rudimentary;
31: * we just notice escaped newlines.
32: */
33: tgetent(bp, name)
34: char *bp, *name;
35: {
36: register char *cp;
37: register int c;
38: register int i = 0, cnt = 0;
39: char ibuf[BUFSIZ];
40: char *cp2;
41: int tf;
42:
43: tbuf = bp;
44: tf = 0;
45: #ifndef V6
46: cp = getenv("TERMCAP");
47: /*
48: * TERMCAP can have one of two things in it. It can be the
49: * name of a file to use instead of /etc/termcap. In this
50: * case it better start with a "/". Or it can be an entry to
51: * use so we don't have to read the file. In this case it
52: * has to already have the newlines crunched out.
53: */
54: if (cp && *cp) {
55: if (*cp!='/') {
56: cp2 = getenv("TERM");
57: if (cp2==(char *) 0 || strcmp(name,cp2)==0) {
58: strcpy(bp,cp);
59: return(tnchktc());
60: } else {
61: tf = open(E_TERMCAP, 0);
62: }
63: } else
64: tf = open(cp, 0);
65: }
66: if (tf==0)
67: tf = open(E_TERMCAP, 0);
68: #else
69: tf = open(E_TERMCAP, 0);
70: #endif
71: if (tf < 0)
72: return (-1);
73: for (;;) {
74: cp = bp;
75: for (;;) {
76: if (i == cnt) {
77: cnt = read(tf, ibuf, BUFSIZ);
78: if (cnt <= 0) {
79: close(tf);
80: return (0);
81: }
82: i = 0;
83: }
84: c = ibuf[i++];
85: if (c == '\n') {
86: if (cp > bp && cp[-1] == '\\'){
87: cp--;
88: continue;
89: }
90: break;
91: }
92: if (cp >= bp+BUFSIZ) {
93: write(2,"Termcap entry too long\n", 23);
94: break;
95: } else
96: *cp++ = c;
97: }
98: *cp = 0;
99:
100: /*
101: * The real work for the match.
102: */
103: if (tnamatch(name)) {
104: close(tf);
105: return(tnchktc());
106: }
107: }
108: }
109:
110: /*
111: * tnchktc: check the last entry, see if it's tc=xxx. If so,
112: * recursively find xxx and append that entry (minus the names)
113: * to take the place of the tc=xxx entry. This allows termcap
114: * entries to say "like an HP2621 but doesn't turn on the labels".
115: * Note that this works because of the left to right scan.
116: */
117: tnchktc()
118: {
119: register char *p, *q;
120: char tcname[16]; /* name of similar terminal */
121: char tcbuf[BUFSIZ];
122: char *holdtbuf = tbuf;
123: int l;
124:
125: p = tbuf + strlen(tbuf) - 2; /* before the last colon */
126: while (*--p != ':')
127: if (p<tbuf) {
128: write(2, "Bad termcap entry\n", 18);
129: return (0);
130: }
131: p++;
132: /* p now points to beginning of last field */
133: if (p[0] != 't' || p[1] != 'c')
134: return(1);
135: strcpy(tcname,p+3);
136: q = tcname;
137: while (q && *q != ':')
138: q++;
139: *q = 0;
140: if (++hopcount > MAXHOP) {
141: write(2, "Infinite tc= loop\n", 18);
142: return (0);
143: }
144: if (tgetent(tcbuf, tcname) != 1)
145: return(0);
146: for (q=tcbuf; *q != ':'; q++)
147: ;
148: l = p - holdtbuf + strlen(q);
149: if (l > BUFSIZ) {
150: write(2, "Termcap entry too long\n", 23);
151: q[BUFSIZ - (p-tbuf)] = 0;
152: }
153: strcpy(p, q+1);
154: tbuf = holdtbuf;
155: return(1);
156: }
157:
158: /*
159: * Tnamatch deals with name matching. The first field of the termcap
160: * entry is a sequence of names separated by |'s, so we compare
161: * against each such name. The normal : terminator after the last
162: * name (before the first field) stops us.
163: */
164: tnamatch(np)
165: char *np;
166: {
167: register char *Np, *Bp;
168:
169: Bp = tbuf;
170: if (*Bp == '#')
171: return(0);
172: for (;;) {
173: for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
174: continue;
175: if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
176: return (1);
177: while (*Bp && *Bp != ':' && *Bp != '|')
178: Bp++;
179: if (*Bp == 0 || *Bp == ':')
180: return (0);
181: Bp++;
182: }
183: }
184:
185: /*
186: * Skip to the next field. Notice that this is very dumb, not
187: * knowing about \: escapes or any such. If necessary, :'s can be put
188: * into the termcap file in octal.
189: */
190: static char *
191: tskip(bp)
192: register char *bp;
193: {
194:
195: while (*bp && *bp != ':')
196: bp++;
197: if (*bp == ':')
198: bp++;
199: return (bp);
200: }
201:
202: /*
203: * Return the (numeric) option id.
204: * Numeric options look like
205: * li#80
206: * i.e. the option string is separated from the numeric value by
207: * a # character. If the option is not found we return -1.
208: * Note that we handle octal numbers beginning with 0.
209: */
210: tgetnum(id)
211: char *id;
212: {
213: register int i, base;
214: register char *bp = tbuf;
215:
216: for (;;) {
217: bp = tskip(bp);
218: if (*bp == 0)
219: return (-1);
220: if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
221: continue;
222: if (*bp == '@')
223: return(-1);
224: if (*bp != '#')
225: continue;
226: bp++;
227: base = 10;
228: if (*bp == '0')
229: base = 8;
230: i = 0;
231: while (isdigit(*bp))
232: i *= base, i += *bp++ - '0';
233: return (i);
234: }
235: }
236:
237: /*
238: * Handle a flag option.
239: * Flag options are given "naked", i.e. followed by a : or the end
240: * of the buffer. Return 1 if we find the option, or 0 if it is
241: * not given.
242: */
243: tgetflag(id)
244: char *id;
245: {
246: register char *bp = tbuf;
247:
248: for (;;) {
249: bp = tskip(bp);
250: if (!*bp)
251: return (0);
252: if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
253: if (!*bp || *bp == ':')
254: return (1);
255: else if (*bp == '@')
256: return(0);
257: }
258: }
259: }
260:
261: /*
262: * Get a string valued option.
263: * These are given as
264: * cl=^Z
265: * Much decoding is done on the strings, and the strings are
266: * placed in area, which is a ref parameter which is updated.
267: * No checking on area overflow.
268: */
269: char *
270: tgetstr(id, area)
271: char *id, **area;
272: {
273: register char *bp = tbuf;
274:
275: for (;;) {
276: bp = tskip(bp);
277: if (!*bp)
278: return (0);
279: if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
280: continue;
281: if (*bp == '@')
282: return(0);
283: if (*bp != '=')
284: continue;
285: bp++;
286: return (tdecode(bp, area));
287: }
288: }
289:
290: /*
291: * Tdecode does the grung work to decode the
292: * string capability escapes.
293: */
294: static char *
295: tdecode(str, area)
296: register char *str;
297: char **area;
298: {
299: register char *cp;
300: register int c;
301: register char *dp;
302: int i;
303:
304: cp = *area;
305: while ((c = *str++) && c != ':') {
306: switch (c) {
307:
308: case '^':
309: c = *str++ & 037;
310: break;
311:
312: case '\\':
313: dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
314: c = *str++;
315: nextc:
316: if (*dp++ == c) {
317: c = *dp++;
318: break;
319: }
320: dp++;
321: if (*dp)
322: goto nextc;
323: if (isdigit(c)) {
324: c -= '0', i = 2;
325: do
326: c <<= 3, c |= *str++ - '0';
327: while (--i && isdigit(*str));
328: }
329: break;
330: }
331: *cp++ = c;
332: }
333: *cp++ = 0;
334: str = *area;
335: *area = cp;
336: return (str);
337: }
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