xref: /netbsd/external/bsd/ntp/dist/ntpd/keyword-gen.c (revision 6550d01e)
1 /*	$NetBSD: keyword-gen.c,v 1.2 2010/11/29 00:39:41 christos Exp $	*/
2 
3 /*
4  * keyword-gen.c -- generate keyword scanner finite state machine and
5  *		    keyword_text array.
6  *		    This program is run to generate ntp_keyword.h
7  */
8 #include <config.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <time.h>
12 
13 #include <ntp_stdlib.h>
14 #include <ntp_config.h>
15 #include <lib_strbuf.h>
16 #include "ntp_scanner.h"
17 #include "ntp_parser.h"
18 
19 
20 #ifdef QSORT_USES_VOID_P
21 typedef const void *	QSORTP;
22 #else
23 typedef char *		QSORTP;
24 #endif
25 
26 /* Define a structure to hold a (keyword, token) pair */
27 struct key_tok {
28 	char *	key;		/* Keyword */
29 	int	token;		/* Associated Token */
30 	follby	followedby;	/* nonzero indicates the next token(s)
31 				   forced to be string(s) */
32 };
33 
34 struct key_tok ntp_keywords[] = {
35 { "automax",		T_Automax,		FOLLBY_TOKEN },
36 { "broadcast",		T_Broadcast,		FOLLBY_STRING },
37 { "broadcastclient",	T_Broadcastclient,	FOLLBY_TOKEN },
38 { "broadcastdelay",	T_Broadcastdelay,	FOLLBY_TOKEN },
39 { "calldelay",		T_Calldelay,		FOLLBY_TOKEN },
40 { "disable",		T_Disable,		FOLLBY_TOKEN },
41 { "driftfile",		T_Driftfile,		FOLLBY_STRING },
42 { "enable",		T_Enable,		FOLLBY_TOKEN },
43 { "end",		T_End,			FOLLBY_TOKEN },
44 { "filegen",		T_Filegen,		FOLLBY_TOKEN },
45 { "fudge",		T_Fudge,		FOLLBY_STRING },
46 { "includefile",	T_Includefile,		FOLLBY_STRING },
47 { "leapfile",		T_Leapfile,		FOLLBY_STRING },
48 { "logconfig",		T_Logconfig,		FOLLBY_STRINGS_TO_EOC },
49 { "logfile",		T_Logfile,		FOLLBY_STRING },
50 { "manycastclient",	T_Manycastclient,	FOLLBY_STRING },
51 { "manycastserver",	T_Manycastserver,	FOLLBY_STRINGS_TO_EOC },
52 { "multicastclient",	T_Multicastclient,	FOLLBY_STRINGS_TO_EOC },
53 { "peer",		T_Peer,			FOLLBY_STRING },
54 { "phone",		T_Phone,		FOLLBY_STRINGS_TO_EOC },
55 { "pidfile",		T_Pidfile,		FOLLBY_STRING },
56 { "pool",		T_Pool,			FOLLBY_STRING },
57 { "discard",		T_Discard,		FOLLBY_TOKEN },
58 { "restrict",		T_Restrict,		FOLLBY_TOKEN },
59 { "server",		T_Server,		FOLLBY_STRING },
60 { "setvar",		T_Setvar,		FOLLBY_STRING },
61 { "statistics",		T_Statistics,		FOLLBY_TOKEN },
62 { "statsdir",		T_Statsdir,		FOLLBY_STRING },
63 { "tick",		T_Tick,			FOLLBY_TOKEN },
64 { "tinker",		T_Tinker,		FOLLBY_TOKEN },
65 { "tos",		T_Tos,			FOLLBY_TOKEN },
66 { "trap",		T_Trap,			FOLLBY_STRING },
67 { "unconfig",		T_Unconfig,		FOLLBY_STRING },
68 { "unpeer",		T_Unpeer,		FOLLBY_STRING },
69 /* authentication_command */
70 { "controlkey",		T_ControlKey,		FOLLBY_TOKEN },
71 { "crypto",		T_Crypto,		FOLLBY_TOKEN },
72 { "keys",		T_Keys,			FOLLBY_STRING },
73 { "keysdir",		T_Keysdir,		FOLLBY_STRING },
74 { "ntpsigndsocket",	T_NtpSignDsocket,	FOLLBY_STRING },
75 { "requestkey",		T_Requestkey,		FOLLBY_TOKEN },
76 { "revoke",		T_Revoke,		FOLLBY_TOKEN },
77 { "trustedkey",		T_Trustedkey,		FOLLBY_TOKEN },
78 /* IPv4/IPv6 protocol override flag */
79 { "-4",			T_Ipv4_flag,		FOLLBY_TOKEN },
80 { "-6",			T_Ipv6_flag,		FOLLBY_TOKEN },
81 /* option */
82 { "autokey",		T_Autokey,		FOLLBY_TOKEN },
83 { "bias",		T_Bias,			FOLLBY_TOKEN },
84 { "burst",		T_Burst,		FOLLBY_TOKEN },
85 { "iburst",		T_Iburst,		FOLLBY_TOKEN },
86 { "key",		T_Key,			FOLLBY_TOKEN },
87 { "maxpoll",		T_Maxpoll,		FOLLBY_TOKEN },
88 { "mdnstries",		T_Mdnstries,		FOLLBY_TOKEN },
89 { "minpoll",		T_Minpoll,		FOLLBY_TOKEN },
90 { "mode",		T_Mode,			FOLLBY_TOKEN },
91 { "noselect",		T_Noselect,		FOLLBY_TOKEN },
92 { "preempt",		T_Preempt,		FOLLBY_TOKEN },
93 { "true",		T_True,			FOLLBY_TOKEN },
94 { "prefer",		T_Prefer,		FOLLBY_TOKEN },
95 { "ttl",		T_Ttl,			FOLLBY_TOKEN },
96 { "version",		T_Version,		FOLLBY_TOKEN },
97 { "xleave",		T_Xleave,		FOLLBY_TOKEN },
98 /* crypto_command */
99 { "host",		T_Host,			FOLLBY_STRING },
100 { "ident",		T_Ident,		FOLLBY_STRING },
101 { "pw",			T_Pw,			FOLLBY_STRING },
102 { "randfile",		T_Randfile,		FOLLBY_STRING },
103 { "sign",		T_Sign,			FOLLBY_STRING },
104 { "digest",		T_Digest,		FOLLBY_STRING },
105 /*** MONITORING COMMANDS ***/
106 /* stat */
107 { "clockstats",		T_Clockstats,		FOLLBY_TOKEN },
108 { "cryptostats",	T_Cryptostats,		FOLLBY_TOKEN },
109 { "loopstats",		T_Loopstats,		FOLLBY_TOKEN },
110 { "peerstats",		T_Peerstats,		FOLLBY_TOKEN },
111 { "rawstats",		T_Rawstats,		FOLLBY_TOKEN },
112 { "sysstats", 		T_Sysstats,		FOLLBY_TOKEN },
113 { "protostats",		T_Protostats,		FOLLBY_TOKEN },
114 { "timingstats",	T_Timingstats,		FOLLBY_TOKEN },
115 /* filegen_option */
116 { "file",		T_File,			FOLLBY_STRING },
117 { "link",		T_Link,			FOLLBY_TOKEN },
118 { "nolink",		T_Nolink,		FOLLBY_TOKEN },
119 { "type",		T_Type,			FOLLBY_TOKEN },
120 /* filegen_type */
121 { "age",		T_Age,			FOLLBY_TOKEN },
122 { "day",		T_Day,			FOLLBY_TOKEN },
123 { "month",		T_Month,		FOLLBY_TOKEN },
124 { "none",		T_None,			FOLLBY_TOKEN },
125 { "pid",		T_Pid,			FOLLBY_TOKEN },
126 { "week",		T_Week,			FOLLBY_TOKEN },
127 { "year",		T_Year,			FOLLBY_TOKEN },
128 /*** ORPHAN MODE COMMANDS ***/
129 /* tos_option */
130 { "minclock",		T_Minclock,		FOLLBY_TOKEN },
131 { "maxclock",		T_Maxclock,		FOLLBY_TOKEN },
132 { "minsane",		T_Minsane,		FOLLBY_TOKEN },
133 { "floor",		T_Floor,		FOLLBY_TOKEN },
134 { "ceiling",		T_Ceiling,		FOLLBY_TOKEN },
135 { "cohort",		T_Cohort,		FOLLBY_TOKEN },
136 { "mindist",		T_Mindist,		FOLLBY_TOKEN },
137 { "maxdist",		T_Maxdist,		FOLLBY_TOKEN },
138 { "beacon",		T_Beacon,		FOLLBY_TOKEN },
139 { "orphan",		T_Orphan,		FOLLBY_TOKEN },
140 /* access_control_flag */
141 { "default",		T_Default,		FOLLBY_TOKEN },
142 { "flake",		T_Flake,		FOLLBY_TOKEN },
143 { "ignore",		T_Ignore,		FOLLBY_TOKEN },
144 { "limited",		T_Limited,		FOLLBY_TOKEN },
145 { "mssntp",		T_Mssntp,		FOLLBY_TOKEN },
146 { "kod",		T_Kod,			FOLLBY_TOKEN },
147 { "lowpriotrap",	T_Lowpriotrap,		FOLLBY_TOKEN },
148 { "mask",		T_Mask,			FOLLBY_TOKEN },
149 { "nomodify",		T_Nomodify,		FOLLBY_TOKEN },
150 { "nopeer",		T_Nopeer,		FOLLBY_TOKEN },
151 { "noquery",		T_Noquery,		FOLLBY_TOKEN },
152 { "noserve",		T_Noserve,		FOLLBY_TOKEN },
153 { "notrap",		T_Notrap,		FOLLBY_TOKEN },
154 { "notrust",		T_Notrust,		FOLLBY_TOKEN },
155 { "ntpport",		T_Ntpport,		FOLLBY_TOKEN },
156 /* discard_option */
157 { "average",		T_Average,		FOLLBY_TOKEN },
158 { "minimum",		T_Minimum,		FOLLBY_TOKEN },
159 { "monitor",		T_Monitor,		FOLLBY_TOKEN },
160 /* fudge_factor */
161 { "flag1",		T_Flag1,		FOLLBY_TOKEN },
162 { "flag2",		T_Flag2,		FOLLBY_TOKEN },
163 { "flag3",		T_Flag3,		FOLLBY_TOKEN },
164 { "flag4",		T_Flag4,		FOLLBY_TOKEN },
165 { "refid",		T_Refid,		FOLLBY_STRING },
166 { "stratum",		T_Stratum,		FOLLBY_TOKEN },
167 { "time1",		T_Time1,		FOLLBY_TOKEN },
168 { "time2",		T_Time2,		FOLLBY_TOKEN },
169 /* system_option */
170 { "auth",		T_Auth,			FOLLBY_TOKEN },
171 { "bclient",		T_Bclient,		FOLLBY_TOKEN },
172 { "calibrate",		T_Calibrate,		FOLLBY_TOKEN },
173 { "kernel",		T_Kernel,		FOLLBY_TOKEN },
174 { "ntp",		T_Ntp,			FOLLBY_TOKEN },
175 { "stats",		T_Stats,		FOLLBY_TOKEN },
176 /* tinker_option */
177 { "step",		T_Step,			FOLLBY_TOKEN },
178 { "panic",		T_Panic,		FOLLBY_TOKEN },
179 { "dispersion",		T_Dispersion,		FOLLBY_TOKEN },
180 { "stepout",		T_Stepout,		FOLLBY_TOKEN },
181 { "allan",		T_Allan,		FOLLBY_TOKEN },
182 { "huffpuff",		T_Huffpuff,		FOLLBY_TOKEN },
183 { "freq",		T_Freq,			FOLLBY_TOKEN },
184 /* miscellaneous_command */
185 { "port",		T_Port,			FOLLBY_TOKEN },
186 { "interface",		T_Interface,		FOLLBY_TOKEN },
187 { "qos",		T_Qos,			FOLLBY_TOKEN },
188 { "saveconfigdir",	T_Saveconfigdir,	FOLLBY_STRING },
189 /* interface_command (ignore and interface already defined) */
190 { "nic",		T_Nic,			FOLLBY_TOKEN },
191 { "all",		T_All,			FOLLBY_TOKEN },
192 { "ipv4",		T_Ipv4,			FOLLBY_TOKEN },
193 { "ipv6",		T_Ipv6,			FOLLBY_TOKEN },
194 { "wildcard",		T_Wildcard,		FOLLBY_TOKEN },
195 { "listen",		T_Listen,		FOLLBY_TOKEN },
196 { "drop",		T_Drop,			FOLLBY_TOKEN },
197 /* simulator commands */
198 { "simulate",		T_Simulate,		FOLLBY_TOKEN },
199 { "simulation_duration",T_Sim_Duration,		FOLLBY_TOKEN },
200 { "beep_delay",		T_Beep_Delay,		FOLLBY_TOKEN },
201 { "duration",		T_Duration,		FOLLBY_TOKEN },
202 { "server_offset",	T_Server_Offset,	FOLLBY_TOKEN },
203 { "freq_offset",	T_Freq_Offset,		FOLLBY_TOKEN },
204 { "wander",		T_Wander,		FOLLBY_TOKEN },
205 { "jitter",		T_Jitter,		FOLLBY_TOKEN },
206 { "prop_delay",		T_Prop_Delay,		FOLLBY_TOKEN },
207 { "proc_delay",		T_Proc_Delay,		FOLLBY_TOKEN },
208 };
209 
210 
211 typedef struct big_scan_state_tag {
212 	char	ch;		/* Character this state matches on */
213 	char	followedby;	/* Forces next token(s) to T_String */
214 	u_short	finishes_token;	/* nonzero ID if last keyword char */
215 	u_short	match_next_s;	/* next state to check matching ch */
216 	u_short	other_next_s;	/* next state to check if not ch */
217 } big_scan_state;
218 
219 /*
220  * Note: to increase MAXSTATES beyond 2048, be aware it is currently
221  * crammed into 11 bits in scan_state form.  Raising to 4096 would be
222  * relatively easy by storing the followedby value in a separate
223  * array with one entry per token, and shrinking the char value to
224  * 7 bits to free a bit for accepting/non-accepting.  More than 4096
225  * states will require expanding scan_state beyond 32 bits each.
226  */
227 #define MAXSTATES 2048
228 
229 const char *	current_keyword;/* for error reporting */
230 big_scan_state	sst[MAXSTATES];	/* scanner FSM state entries */
231 int		sst_highwater;	/* next entry index to consider */
232 char *		symb[1024];	/* map token ID to symbolic name */
233 
234 /* for libntp */
235 const char *	progname = "keyword-gen";
236 volatile int	debug = 1;
237 
238 int		main			(int, char **);
239 static void	generate_preamble	(void);
240 static void	generate_fsm		(void);
241 static void	generate_token_text	(void);
242 static int	create_keyword_scanner	(void);
243 static int	create_scan_states	(char *, int, follby, int);
244 int		compare_key_tok_id	(QSORTP, QSORTP);
245 int		compare_key_tok_text	(QSORTP, QSORTP);
246 void		populate_symb		(char *);
247 const char *	symbname		(int);
248 
249 
250 int main(int argc, char **argv)
251 {
252 	if (argc < 2) {
253 		fprintf(stderr, "Usage:\n%s t_header.h\n", argv[0]);
254 		exit(1);
255 	}
256 	populate_symb(argv[1]);
257 
258 	generate_preamble();
259 	generate_token_text();
260 	generate_fsm();
261 
262 	return 0;
263 }
264 
265 
266 static void
267 generate_preamble(void)
268 {
269 	time_t now;
270 	char timestamp[128];
271 	char preamble[] =
272 "/*\n"
273 " * ntp_keyword.h\n"
274 " * \n"
275 " * NOTE: edit this file with caution, it is generated by keyword-gen.c\n"
276 " *\t Generated %s UTC	  diff_ignore_line\n"
277 " *\n"
278 " */\n"
279 "#include \"ntp_scanner.h\"\n"
280 "#include \"ntp_parser.h\"\n"
281 "\n";
282 
283 	time(&now);
284 	if (!strftime(timestamp, sizeof(timestamp),
285 		      "%Y-%m-%d %H:%M:%S", gmtime(&now)))
286 		timestamp[0] = '\0';
287 
288 	printf(preamble, timestamp);
289 }
290 
291 
292 static void
293 generate_fsm(void)
294 {
295 	char token_id_comment[128];
296 	int initial_state;
297 	int i;
298 	int token;
299 
300 	/*
301 	 * Sort ntp_keywords in alphabetical keyword order.  This is
302 	 * not necessary, but minimizes nonfunctional changes in the
303 	 * generated finite state machine when keywords are modified.
304 	 */
305 	qsort(ntp_keywords, COUNTOF(ntp_keywords),
306 	      sizeof(ntp_keywords[0]), compare_key_tok_text);
307 
308 	/*
309 	 * To save space, reserve the state array entry matching each
310 	 * token number for its terminal state, so the token identifier
311 	 * does not need to be stored in each state, but can be
312 	 * recovered trivially.  To mark the entry reserved,
313 	 * finishes_token is nonzero.
314 	 */
315 
316 	for (i = 0; i < COUNTOF(ntp_keywords); i++) {
317 		token = ntp_keywords[i].token;
318 		if (1 > token || token >= COUNTOF(sst)) {
319 			fprintf(stderr,
320 				"keyword-gen sst[%u] too small "
321 				"for keyword '%s' id %d\n",
322 				(int)COUNTOF(sst),
323 				ntp_keywords[i].key,
324 				token);
325 			exit(4);
326 		}
327 		sst[token].finishes_token = token;
328 	}
329 
330 	initial_state = create_keyword_scanner();
331 
332 	fprintf(stderr,
333 		"%d keywords consumed %d states of %d max.\n",
334 		(int)COUNTOF(ntp_keywords),
335 		sst_highwater - 1,
336 		(int)COUNTOF(sst) - 1);
337 
338 	printf("#define SCANNER_INIT_S %d\n\n", initial_state);
339 
340 	printf("const scan_state sst[%d] = {\n"
341 	       "/*SS_T( ch,\tf-by, match, other ),\t\t\t\t */\n"
342 	       "  0,\t\t\t\t      /* %5d %-17s */\n",
343 	       sst_highwater,
344 	       0, "");
345 
346 	for (i = 1; i < sst_highwater; i++) {
347 
348 		/* verify fields will fit */
349 		if (sst[i].followedby & ~0x3) {
350 			fprintf(stderr,
351 				"keyword-gen internal error "
352 				"sst[%d].followedby %d too big\n",
353 				i, sst[i].followedby);
354 			exit(7);
355 		}
356 
357 		if (sst_highwater <= sst[i].match_next_s
358 		    || sst[i].match_next_s & ~0x7ff) {
359 			fprintf(stderr,
360 				"keyword-gen internal error "
361 				"sst[%d].match_next_s %d too big\n",
362 				i, sst[i].match_next_s);
363 			exit(8);
364 		}
365 
366 		if (sst_highwater <= sst[i].other_next_s
367 		    || sst[i].other_next_s & ~0x7ff) {
368 			fprintf(stderr,
369 				"keyword-gen internal error "
370 				"sst[%d].other_next_s %d too big\n",
371 				i, sst[i].other_next_s);
372 			exit(9);
373 		}
374 
375 		if (!sst[i].finishes_token)
376 			snprintf(token_id_comment,
377 				 sizeof(token_id_comment), "%5d %-17s",
378 				 i, (initial_state == i)
379 					? "initial state"
380 					: "");
381 		else {
382 			snprintf(token_id_comment,
383 				 sizeof(token_id_comment), "%5d %-17s",
384 				 i, symbname(sst[i].finishes_token));
385 			if (i != sst[i].finishes_token) {
386 				fprintf(stderr,
387 					"keyword-gen internal error "
388 					"entry %d finishes token %d\n",
389 					i, sst[i].finishes_token);
390 				exit(5);
391 			}
392 		}
393 
394 		printf("  S_ST( '%c',\t%d,    %5u, %5u )%s /* %s */\n",
395 		       sst[i].ch,
396 		       sst[i].followedby,
397 		       sst[i].match_next_s,
398 		       sst[i].other_next_s,
399 		       (i + 1 < sst_highwater)
400 			   ? ","
401 			   : " ",
402 		       token_id_comment);
403 	}
404 
405 	printf("};\n\n");
406 }
407 
408 
409 /* Define a function to create the states of the scanner. This function
410  * is used by the create_keyword_scanner function below.
411  *
412  * This function takes a suffix of a keyword, the token to be returned on
413  * recognizing the complete keyword, and any pre-existing state that exists
414  * for some other keyword that has the same prefix as the current one.
415  */
416 static int
417 create_scan_states(
418 	char *	text,
419 	int	token,
420 	follby	followedby,
421 	int	prev_state
422 	)
423 {
424 	int my_state;
425 	int return_state;
426 	int prev_char_s;
427 	int curr_char_s;
428 
429 	return_state = prev_state;
430 	curr_char_s = prev_state;
431 	prev_char_s = 0;
432 
433 	/* Find the correct position to insert the state.
434 	 * All states should be in alphabetical order
435 	 */
436 	while (curr_char_s && (text[0] < sst[curr_char_s].ch)) {
437 		prev_char_s = curr_char_s;
438 		curr_char_s = sst[curr_char_s].other_next_s;
439 	}
440 
441 	/*
442 	 * Check if a previously seen keyword has the same prefix as
443 	 * the current keyword.  If so, simply use the state for that
444 	 * keyword as my_state, otherwise, allocate a new state.
445 	 */
446 	if (curr_char_s && (text[0] == sst[curr_char_s].ch)) {
447 		my_state = curr_char_s;
448 		if ('\0' == text[1]) {
449 			fprintf(stderr,
450 				"Duplicate entries for keyword '%s' in"
451 				" keyword_gen.c ntp_keywords[].\n",
452 				current_keyword);
453 			exit(2);
454 		}
455 	} else {
456 		do
457 			my_state = sst_highwater++;
458 		while (my_state < COUNTOF(sst)
459 		       && sst[my_state].finishes_token);
460 		if (my_state >= COUNTOF(sst)) {
461 			fprintf(stderr,
462 				"fatal, keyword scanner state array "
463 				"sst[%d] is too small, modify\n"
464 				"keyword-gen.c to increase.\n",
465 				(int)COUNTOF(sst));
466 			exit(3);
467 		}
468 		/* Store the next character of the keyword */
469 		sst[my_state].ch = text[0];
470 		sst[my_state].other_next_s = curr_char_s;
471 		sst[my_state].followedby = FOLLBY_NON_ACCEPTING;
472 
473 		if (prev_char_s)
474 			sst[prev_char_s].other_next_s = my_state;
475 		else
476 			return_state = my_state;
477 	}
478 
479 	/* Check if the next character is '\0'.
480 	 * If yes, we are done with the recognition and this is an accepting
481 	 * state.
482 	 * If not, we need to continue scanning
483 	 */
484 	if ('\0' == text[1]) {
485 		sst[my_state].finishes_token = (u_short)token;
486 		sst[my_state].followedby = (char)followedby;
487 
488 		if (sst[token].finishes_token != (u_short)token) {
489 			fprintf(stderr,
490 				"fatal, sst[%d] not reserved for %s.\n",
491 				token, symbname(token));
492 			exit(6);
493 		}
494 		/* relocate so token id is sst[] index */
495 		if (my_state != token) {
496 			sst[token] = sst[my_state];
497 			memset(&sst[my_state], 0,
498 			       sizeof(sst[my_state]));
499 			do
500 				sst_highwater--;
501 			while (sst[sst_highwater].finishes_token);
502 			my_state = token;
503 			if (prev_char_s)
504 				sst[prev_char_s].other_next_s = my_state;
505 			else
506 				return_state = my_state;
507 		}
508 	} else
509 		sst[my_state].match_next_s =
510 		    create_scan_states(
511 			&text[1],
512 			token,
513 			followedby,
514 			sst[my_state].match_next_s);
515 
516 	return return_state;
517 }
518 
519 
520 /* Define a function that takes a list of (keyword, token) values and
521  * creates a keywords scanner out of it.
522  */
523 
524 static int
525 create_keyword_scanner(void)
526 {
527 	int scanner;
528 	int i;
529 
530 	sst_highwater = 1;	/* index 0 invalid, unused */
531 	scanner = 0;
532 
533 	for (i = 0; i < COUNTOF(ntp_keywords); i++) {
534 		current_keyword = ntp_keywords[i].key;
535 		scanner =
536 		    create_scan_states(
537 			ntp_keywords[i].key,
538 			ntp_keywords[i].token,
539 			ntp_keywords[i].followedby,
540 			scanner);
541 	}
542 
543 	return scanner;
544 }
545 
546 
547 static void
548 generate_token_text(void)
549 {
550 	int lowest_id;
551 	int highest_id;
552 	int id_count;
553 	int id;
554 	int i;
555 
556 	/* sort ntp_keywords in token ID order */
557 	qsort(ntp_keywords, COUNTOF(ntp_keywords),
558 	      sizeof(ntp_keywords[0]), compare_key_tok_id);
559 
560 	lowest_id = ntp_keywords[0].token;
561 	highest_id = ntp_keywords[COUNTOF(ntp_keywords) - 1].token;
562 	id_count = highest_id - lowest_id + 1;
563 
564 	printf("#define LOWEST_KEYWORD_ID %d\n\n", lowest_id);
565 
566 	printf("const char * const keyword_text[%d] = {", id_count);
567 
568 	id = lowest_id;
569 	i = 0;
570 	while (i < COUNTOF(ntp_keywords)) {
571 		while (id < ntp_keywords[i].token) {
572 			printf(",\n\t/* %-5d %5d %20s */\tNULL",
573 			       id - lowest_id, id, symbname(id));
574 			id++;
575 		}
576 		if (i > 0)
577 			printf(",");
578 		printf("\n\t/* %-5d %5d %20s */\t\"%s\"",
579 		       id - lowest_id, id, symbname(id),
580 		       ntp_keywords[i].key);
581 		i++;
582 		id++;
583 	}
584 
585 	printf("\n};\n\n");
586 }
587 
588 
589 int
590 compare_key_tok_id(
591 	QSORTP a1,
592 	QSORTP a2
593 	)
594 {
595 	const struct key_tok *p1 = (const void *)a1;
596 	const struct key_tok *p2 = (const void *)a2;
597 
598 	if (p1->token == p2->token)
599 		return 0;
600 
601 	if (p1->token < p2->token)
602 		return -1;
603 	else
604 		return 1;
605 }
606 
607 
608 int
609 compare_key_tok_text(
610 	QSORTP a1,
611 	QSORTP a2
612 	)
613 {
614 	const struct key_tok *p1 = (const void *)a1;
615 	const struct key_tok *p2 = (const void *)a2;
616 
617 	return strcmp(p1->key, p2->key);
618 }
619 
620 
621 /*
622  * populate_symb() - populate symb[] lookup array with symbolic token
623  *		     names such that symb[T_Age] == "T_Age", etc.
624  */
625 void
626 populate_symb(
627 	char *header_file
628 	)
629 {
630 	FILE *	yh;
631 	char	line[128];
632 	char	name[128];
633 	int	token;
634 
635 	yh = fopen(header_file, "r");
636 	if (NULL == yh) {
637 		perror("unable to open yacc/bison header file");
638 		exit(4);
639 	}
640 
641 	while (NULL != fgets(line, sizeof(line), yh))
642 		if (2 == sscanf(line, "#define %s %d", name, &token)
643 		    && 'T' == name[0] && '_' == name[1] && token >= 0
644 		    && token < COUNTOF(symb))
645 
646 			symb[token] = estrdup(name);
647 
648 	fclose(yh);
649 }
650 
651 
652 const char *
653 symbname(
654 	int token
655 	)
656 {
657 	char *name;
658 
659 	if (token >= 0 && token < COUNTOF(symb) && symb[token] != NULL)
660 		return symb[token];
661 
662 	LIB_GETBUF(name);
663 	snprintf(name, LIB_BUFLENGTH, "%d", token);
664 	return name;
665 }
666