1 #include <u.h>
2 #include <libc.h>
3 #include <bio.h>
4 	/* Macros for Rune support of ctype.h-like functions */
5 
6 #undef isupper
7 #undef islower
8 #undef isalpha
9 #undef isdigit
10 #undef isalnum
11 #undef isspace
12 #undef tolower
13 #define	isupper(r)	('A' <= (r) && (r) <= 'Z')
14 #define	islower(r)	('a' <= (r) && (r) <= 'z')
15 #define	isalpha(r)	(isupper(r) || islower(r))
16 #define	islatin1(r)	(0xC0 <= (r) && (r) <= 0xFF)
17 
18 #define	isdigit(r)	('0' <= (r) && (r) <= '9')
19 
20 #define	isalnum(r)	(isalpha(r) || isdigit(r))
21 
22 #define	isspace(r)	((r) == ' ' || (r) == '\t' \
23 			|| (0x0A <= (r) && (r) <= 0x0D))
24 
25 #define	tolower(r)	((r)-'A'+'a')
26 
27 #define	sgn(v)		((v) < 0 ? -1 : ((v) > 0 ? 1 : 0))
28 
29 #define	WORDSIZ	4000
30 char	*filename = "#9/lib/words";
31 Biobuf	*dfile;
32 Biobuf	bout;
33 Biobuf	bin;
34 
35 int	fold;
36 int	direc;
37 int	exact;
38 int	iflag;
39 int	rev = 1;	/*-1 for reverse-ordered file, not implemented*/
40 int	(*compare)(Rune*, Rune*);
41 Rune	tab = '\t';
42 Rune	entry[WORDSIZ];
43 Rune	word[WORDSIZ];
44 Rune	key[50], orig[50];
45 Rune	latin_fold_tab[] =
46 {
47 /*	Table to fold latin 1 characters to ASCII equivalents
48 			based at Rune value 0xc0
49 
50 	 À    Á    Â    Ã    Ä    Å    Æ    Ç
51 	 È    É    Ê    Ë    Ì    Í    Î    Ï
52 	 Ð    Ñ    Ò    Ó    Ô    Õ    Ö    ×
53 	 Ø    Ù    Ú    Û    Ü    Ý    Þ    ß
54 	 à    á    â    ã    ä    å    æ    ç
55 	 è    é    ê    ë    ì    í    î    ï
56 	 ð    ñ    ò    ó    ô    õ    ö    ÷
57 	 ø    ù    ú    û    ü    ý    þ    ÿ
58 */
59 	'a', 'a', 'a', 'a', 'a', 'a', 'a', 'c',
60 	'e', 'e', 'e', 'e', 'i', 'i', 'i', 'i',
61 	'd', 'n', 'o', 'o', 'o', 'o', 'o',  0 ,
62 	'o', 'u', 'u', 'u', 'u', 'y',  0 ,  0 ,
63 	'a', 'a', 'a', 'a', 'a', 'a', 'a', 'c',
64 	'e', 'e', 'e', 'e', 'i', 'i', 'i', 'i',
65 	'd', 'n', 'o', 'o', 'o', 'o', 'o',  0 ,
66 	'o', 'u', 'u', 'u', 'u', 'y',  0 , 'y',
67 };
68 
69 int	locate(void);
70 int	acomp(Rune*, Rune*);
71 int	getword(Biobuf*, Rune *rp, int n);
72 void	torune(char*, Rune*);
73 void	rcanon(Rune*, Rune*);
74 int	ncomp(Rune*, Rune*);
75 
76 void
77 main(int argc, char *argv[])
78 {
79 	int n;
80 
81 	filename = unsharp(filename);
82 
83 	Binit(&bin, 0, OREAD);
84 	Binit(&bout, 1, OWRITE);
85 	compare = acomp;
86 	ARGBEGIN{
87 	case 'd':
88 		direc++;
89 		break;
90 	case 'f':
91 		fold++;
92 		break;
93 	case 'i':
94 		iflag++;
95 		break;
96 	case 'n':
97 		compare = ncomp;
98 		break;
99 	case 't':
100 		chartorune(&tab,ARGF());
101 		break;
102 	case 'x':
103 		exact++;
104 		break;
105 	default:
106 		fprint(2, "%s: bad option %c\n", argv0, ARGC());
107 		fprint(2, "usage: %s -[dfinx] [-t c] [string] [file]\n", argv0);
108 		exits("usage");
109 	} ARGEND
110 	if(!iflag){
111 		if(argc >= 1) {
112 			torune(argv[0], orig);
113 			argv++;
114 			argc--;
115 		} else
116 			iflag++;
117 	}
118 	if(argc < 1) {
119 		direc++;
120 		fold++;
121 	} else
122 		filename = argv[0];
123 	if (!iflag)
124 		rcanon(orig, key);
125 	dfile = Bopen(filename, OREAD);
126 	if(dfile == 0) {
127 		fprint(2, "look: can't open %s\n", filename);
128 		exits("no dictionary");
129 	}
130 	if(!iflag)
131 		if(!locate())
132 			exits("not found");
133 	do {
134 		if(iflag) {
135 			Bflush(&bout);
136 			if(!getword(&bin, orig, sizeof(orig)/sizeof(orig[0])))
137 				exits(0);
138 			rcanon(orig, key);
139 			if(!locate())
140 				continue;
141 		}
142 		if (!exact || !acomp(word, key))
143 			Bprint(&bout, "%S\n", entry);
144 		while(getword(dfile, entry, sizeof(entry)/sizeof(entry[0]))) {
145 			rcanon(entry, word);
146 			n = compare(key, word);
147 			switch(n) {
148 			case -1:
149 				if(exact)
150 					break;
151 			case 0:
152 				if (!exact || !acomp(word, orig))
153 					Bprint(&bout, "%S\n", entry);
154 				continue;
155 			}
156 			break;
157 		}
158 	} while(iflag);
159 	exits(0);
160 }
161 
162 int
163 locate(void)
164 {
165 	vlong top, bot, mid;
166 	int c;
167 	int n;
168 
169 	bot = 0;
170 	top = Bseek(dfile, 0L, 2);
171 	for(;;) {
172 		mid = (top+bot) / 2;
173 		Bseek(dfile, mid, 0);
174 		do
175 			c = Bgetrune(dfile);
176 		while(c>=0 && c!='\n');
177 		mid = Boffset(dfile);
178 		if(!getword(dfile, entry, sizeof(entry)/sizeof(entry[0])))
179 			break;
180 		rcanon(entry, word);
181 		n = compare(key, word);
182 		switch(n) {
183 		case -2:
184 		case -1:
185 		case 0:
186 			if(top <= mid)
187 				break;
188 			top = mid;
189 			continue;
190 		case 1:
191 		case 2:
192 			bot = mid;
193 			continue;
194 		}
195 		break;
196 	}
197 	Bseek(dfile, bot, 0);
198 	while(getword(dfile, entry, sizeof(entry)/sizeof(entry[0]))) {
199 		rcanon(entry, word);
200 		n = compare(key, word);
201 		switch(n) {
202 		case -2:
203 			return 0;
204 		case -1:
205 			if(exact)
206 				return 0;
207 		case 0:
208 			return 1;
209 		case 1:
210 		case 2:
211 			continue;
212 		}
213 	}
214 	return 0;
215 }
216 
217 /*
218  *	acomp(s, t) returns:
219  *		-2 if s strictly precedes t
220  *		-1 if s is a prefix of t
221  *		0 if s is the same as t
222  *		1 if t is a prefix of s
223  *		2 if t strictly precedes s
224  */
225 
226 int
227 acomp(Rune *s, Rune *t)
228 {
229 	int cs, ct;
230 
231 	for(;;) {
232 		cs = *s;
233 		ct = *t;
234 		if(cs != ct)
235 			break;
236 		if(cs == 0)
237 			return 0;
238 		s++;
239 		t++;
240 	}
241 	if(cs == 0)
242 		return -1;
243 	if(ct == 0)
244 		return 1;
245 	if(cs < ct)
246 		return -2;
247 	return 2;
248 }
249 
250 void
251 torune(char *old, Rune *new)
252 {
253 	do old += chartorune(new, old);
254 	while(*new++);
255 }
256 
257 void
258 rcanon(Rune *old, Rune *new)
259 {
260 	Rune r;
261 
262 	while((r = *old++) && r != tab) {
263 		if (islatin1(r) && latin_fold_tab[r-0xc0])
264 				r = latin_fold_tab[r-0xc0];
265 		if(direc)
266 			if(!(isalnum(r) || r == ' ' || r == '\t'))
267 				continue;
268 		if(fold)
269 			if(isupper(r))
270 				r = tolower(r);
271 		*new++ = r;
272 	}
273 	*new = 0;
274 }
275 
276 int
277 ncomp(Rune *s, Rune *t)
278 {
279 	Rune *is, *it, *js, *jt;
280 	int a, b;
281 	int ssgn, tsgn;
282 
283 	while(isspace(*s))
284 		s++;
285 	while(isspace(*t))
286 		t++;
287 	ssgn = tsgn = -2*rev;
288 	if(*s == '-') {
289 		s++;
290 		ssgn = -ssgn;
291 	}
292 	if(*t == '-') {
293 		t++;
294 		tsgn = -tsgn;
295 	}
296 	for(is = s; isdigit(*is); is++)
297 		;
298 	for(it = t; isdigit(*it); it++)
299 		;
300 	js = is;
301 	jt = it;
302 	a = 0;
303 	if(ssgn == tsgn)
304 		while(it>t && is>s)
305 			if(b = *--it - *--is)
306 				a = b;
307 	while(is > s)
308 		if(*--is != '0')
309 			return -ssgn;
310 	while(it > t)
311 		if(*--it != '0')
312 			return tsgn;
313 	if(a)
314 		return sgn(a)*ssgn;
315 	if(*(s=js) == '.')
316 		s++;
317 	if(*(t=jt) == '.')
318 		t++;
319 	if(ssgn == tsgn)
320 		while(isdigit(*s) && isdigit(*t))
321 			if(a = *t++ - *s++)
322 				return sgn(a)*ssgn;
323 	while(isdigit(*s))
324 		if(*s++ != '0')
325 			return -ssgn;
326 	while(isdigit(*t))
327 		if(*t++ != '0')
328 			return tsgn;
329 	return 0;
330 }
331 
332 int
333 getword(Biobuf *f, Rune *rp, int n)
334 {
335 	long c;
336 
337 	while(n-- > 0) {
338 		c = Bgetrune(f);
339 		if(c < 0)
340 			return 0;
341 		if(c == '\n') {
342 			*rp = '\0';
343 			return 1;
344 		}
345 		*rp++ = c;
346 	}
347 	fprint(2, "Look: word too long.  Bailing out.\n");
348 	return 0;
349 }