1 /*
2 * keyword-gen.c -- generate keyword scanner finite state machine and
3 * keyword_text array.
4 *
5 * This program is run to generate ntp_keyword.h
6 * After making a change here, two output files should be committed at
7 * the same time as keyword-gen.c:
8 * ntp_keyword.h
9 * keyword-gen-utd
10 *
11 * keyword-gen-utd is a sentinel used by Makefile.am to avoid compiling
12 * keyword_gen.c and generating ntp_keyword.h if the input keyword-gen.c
13 * has not changed. This is not solely an optimization, it also breaks
14 * a dependency chain that otherwise would cause programs to be compiled
15 * when running "make dist" or "make distdir". We want these to package
16 * the existing source without building anything but a tarball. See
17 * [Bug 1470].
18 */
19 #include <config.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <time.h>
23
24 #include <ntp_stdlib.h>
25 #include <ntp_config.h>
26 #include "ntp_scanner.h"
27 #include "ntp_parser.h"
28
29
30 /* Define a structure to hold a (keyword, token) pair */
31 struct key_tok {
32 char * key; /* Keyword */
33 u_short token; /* Associated Token */
34 follby followedby; /* nonzero indicates the next token(s)
35 forced to be string(s) */
36 };
37
38 struct key_tok ntp_keywords[] = {
39 { "...", T_Ellipsis, FOLLBY_TOKEN },
40 { "allpeers", T_Allpeers, FOLLBY_TOKEN },
41 { "automax", T_Automax, FOLLBY_TOKEN },
42 { "broadcast", T_Broadcast, FOLLBY_STRING },
43 { "broadcastclient", T_Broadcastclient, FOLLBY_TOKEN },
44 { "broadcastdelay", T_Broadcastdelay, FOLLBY_TOKEN },
45 { "checkhash", T_Checkhash, FOLLBY_TOKEN },
46 { "ctl", T_Ctl, FOLLBY_TOKEN },
47 { "delrestrict", T_Delrestrict, FOLLBY_TOKEN },
48 { "device", T_Device, FOLLBY_STRING },
49 { "disable", T_Disable, FOLLBY_TOKEN },
50 { "driftfile", T_Driftfile, FOLLBY_STRING },
51 { "dscp", T_Dscp, FOLLBY_TOKEN },
52 { "enable", T_Enable, FOLLBY_TOKEN },
53 { "end", T_End, FOLLBY_TOKEN },
54 { "filegen", T_Filegen, FOLLBY_TOKEN },
55 { "fudge", T_Fudge, FOLLBY_STRING },
56 { "ignorehash", T_Ignorehash, FOLLBY_TOKEN },
57 { "io", T_Io, FOLLBY_TOKEN },
58 { "includefile", T_Includefile, FOLLBY_STRING },
59 { "leapfile", T_Leapfile, FOLLBY_STRING },
60 { "leapsmearinterval", T_Leapsmearinterval, FOLLBY_TOKEN },
61 { "logconfig", T_Logconfig, FOLLBY_STRINGS_TO_EOC },
62 { "logfile", T_Logfile, FOLLBY_STRING },
63 { "manycastclient", T_Manycastclient, FOLLBY_STRING },
64 { "manycastserver", T_Manycastserver, FOLLBY_STRINGS_TO_EOC },
65 { "mem", T_Mem, FOLLBY_TOKEN },
66 { "multicastclient", T_Multicastclient, FOLLBY_STRINGS_TO_EOC },
67 { "peer", T_Peer, FOLLBY_STRING },
68 { "phone", T_Phone, FOLLBY_STRINGS_TO_EOC },
69 { "pidfile", T_Pidfile, FOLLBY_STRING },
70 { "pollskewlist", T_PollSkewList, FOLLBY_TOKEN },
71 { "pool", T_Pool, FOLLBY_STRING },
72 { "discard", T_Discard, FOLLBY_TOKEN },
73 { "reset", T_Reset, FOLLBY_TOKEN },
74 { "restrict", T_Restrict, FOLLBY_TOKEN },
75 { "rlimit", T_Rlimit, FOLLBY_TOKEN },
76 { "server", T_Server, FOLLBY_STRING },
77 { "serverresponse", T_Serverresponse, FOLLBY_TOKEN },
78 { "fuzz", T_Fuzz, FOLLBY_TOKEN },
79 { "poll", T_Poll, FOLLBY_TOKEN },
80 { "setvar", T_Setvar, FOLLBY_STRING },
81 { "statistics", T_Statistics, FOLLBY_TOKEN },
82 { "statsdir", T_Statsdir, FOLLBY_STRING },
83 { "sys", T_Sys, FOLLBY_TOKEN },
84 { "tick", T_Tick, FOLLBY_TOKEN },
85 { "timer", T_Timer, FOLLBY_TOKEN },
86 { "tinker", T_Tinker, FOLLBY_TOKEN },
87 { "tos", T_Tos, FOLLBY_TOKEN },
88 { "trap", T_Trap, FOLLBY_STRING },
89 { "unconfig", T_Unconfig, FOLLBY_STRING },
90 { "unpeer", T_Unpeer, FOLLBY_STRING },
91 { "xmtnonce", T_Xmtnonce, FOLLBY_TOKEN },
92 /* authentication_command */
93 { "controlkey", T_ControlKey, FOLLBY_TOKEN },
94 { "crypto", T_Crypto, FOLLBY_TOKEN },
95 { "keys", T_Keys, FOLLBY_STRING },
96 { "keysdir", T_Keysdir, FOLLBY_STRING },
97 { "ntpsigndsocket", T_NtpSignDsocket, FOLLBY_STRING },
98 { "requestkey", T_Requestkey, FOLLBY_TOKEN },
99 { "revoke", T_Revoke, FOLLBY_TOKEN },
100 { "trustedkey", T_Trustedkey, FOLLBY_TOKEN },
101 /* IPv4/IPv6 protocol override flag */
102 { "-4", T_Ipv4_flag, FOLLBY_TOKEN },
103 { "-6", T_Ipv6_flag, FOLLBY_TOKEN },
104 /* option */
105 { "autokey", T_Autokey, FOLLBY_TOKEN },
106 { "burst", T_Burst, FOLLBY_TOKEN },
107 { "iburst", T_Iburst, FOLLBY_TOKEN },
108 { "key", T_Key, FOLLBY_TOKEN },
109 { "maxpoll", T_Maxpoll, FOLLBY_TOKEN },
110 { "mdnstries", T_Mdnstries, FOLLBY_TOKEN },
111 { "minpoll", T_Minpoll, FOLLBY_TOKEN },
112 { "mode", T_Mode, FOLLBY_TOKEN },
113 { "noselect", T_Noselect, FOLLBY_TOKEN },
114 { "preempt", T_Preempt, FOLLBY_TOKEN },
115 { "true", T_True, FOLLBY_TOKEN },
116 { "prefer", T_Prefer, FOLLBY_TOKEN },
117 { "ttl", T_Ttl, FOLLBY_TOKEN },
118 { "version", T_Version, FOLLBY_TOKEN },
119 { "xleave", T_Xleave, FOLLBY_TOKEN },
120 /* crypto_command */
121 { "host", T_Host, FOLLBY_STRING },
122 { "ident", T_Ident, FOLLBY_STRING },
123 { "pw", T_Pw, FOLLBY_STRING },
124 { "randfile", T_Randfile, FOLLBY_STRING },
125 { "digest", T_Digest, FOLLBY_STRING },
126 /*** MONITORING COMMANDS ***/
127 /* stat */
128 { "clockstats", T_Clockstats, FOLLBY_TOKEN },
129 { "cryptostats", T_Cryptostats, FOLLBY_TOKEN },
130 { "loopstats", T_Loopstats, FOLLBY_TOKEN },
131 { "peerstats", T_Peerstats, FOLLBY_TOKEN },
132 { "rawstats", T_Rawstats, FOLLBY_TOKEN },
133 { "sysstats", T_Sysstats, FOLLBY_TOKEN },
134 { "protostats", T_Protostats, FOLLBY_TOKEN },
135 { "timingstats", T_Timingstats, FOLLBY_TOKEN },
136 /* filegen_option */
137 { "file", T_File, FOLLBY_STRING },
138 { "link", T_Link, FOLLBY_TOKEN },
139 { "nolink", T_Nolink, FOLLBY_TOKEN },
140 { "type", T_Type, FOLLBY_TOKEN },
141 /* filegen_type */
142 { "age", T_Age, FOLLBY_TOKEN },
143 { "day", T_Day, FOLLBY_TOKEN },
144 { "month", T_Month, FOLLBY_TOKEN },
145 { "none", T_None, FOLLBY_TOKEN },
146 { "pid", T_Pid, FOLLBY_TOKEN },
147 { "week", T_Week, FOLLBY_TOKEN },
148 { "year", T_Year, FOLLBY_TOKEN },
149 /*** ORPHAN MODE COMMANDS ***/
150 /* tos_option */
151 { "minclock", T_Minclock, FOLLBY_TOKEN },
152 { "maxclock", T_Maxclock, FOLLBY_TOKEN },
153 { "minsane", T_Minsane, FOLLBY_TOKEN },
154 { "floor", T_Floor, FOLLBY_TOKEN },
155 { "ceiling", T_Ceiling, FOLLBY_TOKEN },
156 { "cohort", T_Cohort, FOLLBY_TOKEN },
157 { "mindist", T_Mindist, FOLLBY_TOKEN },
158 { "maxdist", T_Maxdist, FOLLBY_TOKEN },
159 { "bcpollbstep", T_Bcpollbstep, FOLLBY_TOKEN },
160 { "beacon", T_Beacon, FOLLBY_TOKEN },
161 { "orphan", T_Orphan, FOLLBY_TOKEN },
162 { "orphanwait", T_Orphanwait, FOLLBY_TOKEN },
163 { "nonvolatile", T_Nonvolatile, FOLLBY_TOKEN },
164 { "basedate", T_Basedate, FOLLBY_STRING },
165 /* access_control_flag */
166 { "default", T_Default, FOLLBY_TOKEN },
167 { "source", T_Source, FOLLBY_TOKEN },
168 { "epeer", T_Epeer, FOLLBY_TOKEN },
169 { "noepeer", T_Noepeer, FOLLBY_TOKEN },
170 { "flake", T_Flake, FOLLBY_TOKEN },
171 { "ignore", T_Ignore, FOLLBY_TOKEN },
172 { "ippeerlimit", T_Ippeerlimit, FOLLBY_TOKEN },
173 { "limited", T_Limited, FOLLBY_TOKEN },
174 { "mssntp", T_Mssntp, FOLLBY_TOKEN },
175 { "kod", T_Kod, FOLLBY_TOKEN },
176 { "lowpriotrap", T_Lowpriotrap, FOLLBY_TOKEN },
177 { "mask", T_Mask, FOLLBY_TOKEN },
178 { "nomodify", T_Nomodify, FOLLBY_TOKEN },
179 { "nomrulist", T_Nomrulist, FOLLBY_TOKEN },
180 { "nopeer", T_Nopeer, FOLLBY_TOKEN },
181 { "noquery", T_Noquery, FOLLBY_TOKEN },
182 { "noserve", T_Noserve, FOLLBY_TOKEN },
183 { "notrap", T_Notrap, FOLLBY_TOKEN },
184 { "notrust", T_Notrust, FOLLBY_TOKEN },
185 { "ntpport", T_Ntpport, FOLLBY_TOKEN },
186 /* discard_option */
187 { "average", T_Average, FOLLBY_TOKEN },
188 { "minimum", T_Minimum, FOLLBY_TOKEN },
189 { "monitor", T_Monitor, FOLLBY_TOKEN },
190 /* mru_option */
191 { "incalloc", T_Incalloc, FOLLBY_TOKEN },
192 { "incmem", T_Incmem, FOLLBY_TOKEN },
193 { "initalloc", T_Initalloc, FOLLBY_TOKEN },
194 { "initmem", T_Initmem, FOLLBY_TOKEN },
195 { "mindepth", T_Mindepth, FOLLBY_TOKEN },
196 { "maxage", T_Maxage, FOLLBY_TOKEN },
197 { "maxdepth", T_Maxdepth, FOLLBY_TOKEN },
198 { "maxmem", T_Maxmem, FOLLBY_TOKEN },
199 { "mru", T_Mru, FOLLBY_TOKEN },
200 /* fudge_factor */
201 { "abbrev", T_Abbrev, FOLLBY_STRING },
202 { "flag1", T_Flag1, FOLLBY_TOKEN },
203 { "flag2", T_Flag2, FOLLBY_TOKEN },
204 { "flag3", T_Flag3, FOLLBY_TOKEN },
205 { "flag4", T_Flag4, FOLLBY_TOKEN },
206 { "refid", T_Refid, FOLLBY_STRING },
207 { "stratum", T_Stratum, FOLLBY_TOKEN },
208 { "time1", T_Time1, FOLLBY_TOKEN },
209 { "time2", T_Time2, FOLLBY_TOKEN },
210 { "minjitter", T_Minjitter, FOLLBY_TOKEN },
211 /* device spec */
212 { "ppsdata", T_PpsData, FOLLBY_STRING },
213 { "timedata", T_TimeData, FOLLBY_STRING },
214 /* system_option */
215 { "auth", T_Auth, FOLLBY_TOKEN },
216 { "bclient", T_Bclient, FOLLBY_TOKEN },
217 { "calibrate", T_Calibrate, FOLLBY_TOKEN },
218 { "kernel", T_Kernel, FOLLBY_TOKEN },
219 { "mode7", T_Mode7, FOLLBY_TOKEN },
220 { "ntp", T_Ntp, FOLLBY_TOKEN },
221 { "peer_clear_digest_early", T_PCEdigest, FOLLBY_TOKEN },
222 { "stats", T_Stats, FOLLBY_TOKEN },
223 { "unpeer_crypto_early", T_UEcrypto, FOLLBY_TOKEN },
224 { "unpeer_crypto_nak_early", T_UEcryptonak, FOLLBY_TOKEN },
225 { "unpeer_digest_early", T_UEdigest, FOLLBY_TOKEN },
226 /* rlimit_option */
227 { "memlock", T_Memlock, FOLLBY_TOKEN },
228 { "stacksize", T_Stacksize, FOLLBY_TOKEN },
229 { "filenum", T_Filenum, FOLLBY_TOKEN },
230 /* tinker_option */
231 { "step", T_Step, FOLLBY_TOKEN },
232 { "stepback", T_Stepback, FOLLBY_TOKEN },
233 { "stepfwd", T_Stepfwd, FOLLBY_TOKEN },
234 { "panic", T_Panic, FOLLBY_TOKEN },
235 { "dispersion", T_Dispersion, FOLLBY_TOKEN },
236 { "stepout", T_Stepout, FOLLBY_TOKEN },
237 { "allan", T_Allan, FOLLBY_TOKEN },
238 { "huffpuff", T_Huffpuff, FOLLBY_TOKEN },
239 { "freq", T_Freq, FOLLBY_TOKEN },
240 /* miscellaneous_command */
241 { "port", T_Port, FOLLBY_TOKEN },
242 { "interface", T_Interface, FOLLBY_TOKEN },
243 { "saveconfigdir", T_Saveconfigdir, FOLLBY_STRING },
244 /* interface_command (ignore and interface already defined) */
245 { "nic", T_Nic, FOLLBY_TOKEN },
246 { "all", T_All, FOLLBY_TOKEN },
247 { "ipv4", T_Ipv4, FOLLBY_TOKEN },
248 { "ipv6", T_Ipv6, FOLLBY_TOKEN },
249 { "wildcard", T_Wildcard, FOLLBY_TOKEN },
250 { "listen", T_Listen, FOLLBY_TOKEN },
251 { "drop", T_Drop, FOLLBY_TOKEN },
252 /* simulator commands */
253 { "simulate", T_Simulate, FOLLBY_TOKEN },
254 { "simulation_duration",T_Sim_Duration, FOLLBY_TOKEN },
255 { "beep_delay", T_Beep_Delay, FOLLBY_TOKEN },
256 { "duration", T_Duration, FOLLBY_TOKEN },
257 { "server_offset", T_Server_Offset, FOLLBY_TOKEN },
258 { "freq_offset", T_Freq_Offset, FOLLBY_TOKEN },
259 { "wander", T_Wander, FOLLBY_TOKEN },
260 { "jitter", T_Jitter, FOLLBY_TOKEN },
261 { "prop_delay", T_Prop_Delay, FOLLBY_TOKEN },
262 { "proc_delay", T_Proc_Delay, FOLLBY_TOKEN },
263 };
264
265 typedef struct big_scan_state_tag {
266 char ch; /* Character this state matches on */
267 char followedby; /* Forces next token(s) to T_String */
268 u_short finishes_token; /* nonzero ID if last keyword char */
269 u_short match_next_s; /* next state to check matching ch */
270 u_short other_next_s; /* next state to check if not ch */
271 } big_scan_state;
272
273 /*
274 * Note: to increase MAXSTATES beyond 2048, be aware it is currently
275 * crammed into 11 bits in scan_state form. Raising to 4096 would be
276 * relatively easy by storing the followedby value in a separate
277 * array with one entry per token, and shrinking the char value to
278 * 7 bits to free a bit for accepting/non-accepting. More than 4096
279 * states will require expanding scan_state beyond 32 bits each.
280 */
281 #define MAXSTATES 2048
282 #define MAX_TOK_LEN 63
283
284 const char * current_keyword;/* for error reporting */
285 big_scan_state sst[MAXSTATES]; /* scanner FSM state entries */
286 u_short sst_highwater; /* next entry index to consider */
287 char * symb[1024]; /* map token ID to symbolic name */
288
289 /* for libntp */
290 const char * progname = "keyword-gen";
291
292 int main (int, char **);
293 static void generate_preamble (void);
294 static void generate_fsm (void);
295 static void generate_token_text (void);
296 static u_short create_keyword_scanner (void);
297 static u_short create_scan_states (char *, u_short, follby, u_short);
298 int compare_key_tok_id (const void *, const void *);
299 int compare_key_tok_text (const void *, const void *);
300 void populate_symb (char *);
301 const char * symbname (u_short);
302
303
main(int argc,char ** argv)304 int main(int argc, char **argv)
305 {
306 if (argc < 2) {
307 fprintf(stderr, "Usage:\n%s t_header.h\n", argv[0]);
308 exit(1);
309 }
310 debug = 1;
311
312 populate_symb(argv[1]);
313
314 generate_preamble();
315 generate_token_text();
316 generate_fsm();
317
318 return 0;
319 }
320
321
322 static void
generate_preamble(void)323 generate_preamble(void)
324 {
325 time_t now;
326 char timestamp[128];
327 char preamble[] =
328 "/*\n"
329 " * ntp_keyword.h\n"
330 " * \n"
331 " * NOTE: edit this file with caution, it is generated by keyword-gen.c\n"
332 " *\t Generated %s UTC diff_ignore_line\n"
333 " *\n"
334 " */\n"
335 "#include \"ntp_scanner.h\"\n"
336 "#include \"ntp_parser.h\"\n"
337 "\n";
338
339 time(&now);
340 if (!strftime(timestamp, sizeof(timestamp),
341 "%Y-%m-%d %H:%M:%S", gmtime(&now)))
342 timestamp[0] = '\0';
343
344 printf(preamble, timestamp);
345 }
346
347
348 static void
generate_fsm(void)349 generate_fsm(void)
350 {
351 char rprefix[MAX_TOK_LEN + 1];
352 char prefix[MAX_TOK_LEN + 1];
353 char token_id_comment[16 + MAX_TOK_LEN + 1];
354 size_t prefix_len;
355 char *p;
356 char *r;
357 u_short initial_state;
358 u_short this_state;
359 u_short state;
360 u_short i;
361 u_short token;
362
363 /*
364 * Sort ntp_keywords in alphabetical keyword order. This is
365 * not necessary, but minimizes nonfunctional changes in the
366 * generated finite state machine when keywords are modified.
367 */
368 qsort(ntp_keywords, COUNTOF(ntp_keywords),
369 sizeof(ntp_keywords[0]), compare_key_tok_text);
370
371 /*
372 * To save space, reserve the state array entry matching each
373 * token number for its terminal state, so the token identifier
374 * does not need to be stored in each state, but can be
375 * recovered trivially. To mark the entry reserved,
376 * finishes_token is nonzero.
377 */
378
379 for (i = 0; i < COUNTOF(ntp_keywords); i++) {
380 token = ntp_keywords[i].token;
381 if (1 > token || token >= COUNTOF(sst)) {
382 fprintf(stderr,
383 "keyword-gen sst[%u] too small "
384 "for keyword '%s' id %d\n",
385 (int)COUNTOF(sst),
386 ntp_keywords[i].key,
387 token);
388 exit(4);
389 }
390 sst[token].finishes_token = token;
391 }
392
393 initial_state = create_keyword_scanner();
394
395 fprintf(stderr,
396 "%d keywords consumed %d states of %d max.\n",
397 (int)COUNTOF(ntp_keywords),
398 sst_highwater - 1,
399 (int)COUNTOF(sst) - 1);
400
401 printf("#define SCANNER_INIT_S %d\n\n", initial_state);
402
403 printf("const scan_state sst[%d] = {\n"
404 "/*SS_T( ch,\tf-by, match, other ),\t\t\t\t */\n"
405 " 0,\t\t\t\t /* %5d %-17s */\n",
406 sst_highwater,
407 0, "");
408
409 for (i = 1; i < sst_highwater; i++) {
410
411 /* verify fields will fit */
412 if (sst[i].followedby & ~0x3) {
413 fprintf(stderr,
414 "keyword-gen internal error "
415 "sst[%d].followedby %d too big\n",
416 i, sst[i].followedby);
417 exit(7);
418 }
419
420 if (sst_highwater <= sst[i].match_next_s
421 || sst[i].match_next_s & ~0x7ff) {
422 fprintf(stderr,
423 "keyword-gen internal error "
424 "sst[%d].match_next_s %d too big\n",
425 i, sst[i].match_next_s);
426 exit(8);
427 }
428
429 if (sst_highwater <= sst[i].other_next_s
430 || sst[i].other_next_s & ~0x7ff) {
431 fprintf(stderr,
432 "keyword-gen internal error "
433 "sst[%d].other_next_s %d too big\n",
434 i, sst[i].other_next_s);
435 exit(9);
436 }
437
438 if (sst[i].finishes_token) {
439 snprintf(token_id_comment,
440 sizeof(token_id_comment), "%5d %-17s",
441 i, symbname(sst[i].finishes_token));
442 if (i != sst[i].finishes_token) {
443 fprintf(stderr,
444 "keyword-gen internal error "
445 "entry %d finishes token %d\n",
446 i, sst[i].finishes_token);
447 exit(5);
448 }
449 } else {
450 /*
451 * Determine the keyword prefix that leads to this
452 * state. This is expensive but keyword-gen is run
453 * only when it changes. Distributing keyword-gen-utd
454 * achieves that, which is why it must be committed
455 * at the same time as keyword-gen.c and ntp_keyword.h.
456 *
457 * Scan the state array iteratively looking for a state
458 * which leads to the current one, collecting matching
459 * characters along the way. There is only one such
460 * path back to the starting state given the way our
461 * scanner state machine is built and the practice of
462 * using the spelling of the keyword as its T_* token
463 * identifier, which results in never having two
464 * spellings result in the same T_* value.
465 */
466 prefix_len = 0;
467 this_state = i;
468 do {
469 for (state = 1; state < sst_highwater; state++)
470 if (sst[state].other_next_s == this_state) {
471 this_state = state;
472 break;
473 } else if (sst[state].match_next_s == this_state) {
474 this_state = state;
475 rprefix[prefix_len] = sst[state].ch;
476 prefix_len++;
477 break;
478 }
479 } while (this_state != initial_state);
480
481 if (prefix_len) {
482 /* reverse rprefix into prefix */
483 p = prefix + prefix_len;
484 r = rprefix;
485 while (r < rprefix + prefix_len)
486 *--p = *r++;
487 }
488 prefix[prefix_len] = '\0';
489
490 snprintf(token_id_comment,
491 sizeof(token_id_comment), "%5d %-17s",
492 i, (initial_state == i)
493 ? "[initial state]"
494 : prefix);
495 }
496
497 printf(" S_ST( '%c',\t%d, %5u, %5u )%s /* %s */\n",
498 sst[i].ch,
499 sst[i].followedby,
500 sst[i].match_next_s,
501 sst[i].other_next_s,
502 (i + 1 < sst_highwater)
503 ? ","
504 : " ",
505 token_id_comment);
506 }
507
508 printf("};\n\n");
509 }
510
511
512 /* Define a function to create the states of the scanner. This function
513 * is used by the create_keyword_scanner function below.
514 *
515 * This function takes a suffix of a keyword, the token to be returned on
516 * recognizing the complete keyword, and any pre-existing state that exists
517 * for some other keyword that has the same prefix as the current one.
518 */
519 static u_short
create_scan_states(char * text,u_short token,follby followedby,u_short prev_state)520 create_scan_states(
521 char * text,
522 u_short token,
523 follby followedby,
524 u_short prev_state
525 )
526 {
527 u_short my_state;
528 u_short return_state;
529 u_short prev_char_s;
530 u_short curr_char_s;
531
532 return_state = prev_state;
533 curr_char_s = prev_state;
534 prev_char_s = 0;
535
536 /* Find the correct position to insert the state.
537 * All states should be in alphabetical order
538 */
539 while (curr_char_s && (text[0] < sst[curr_char_s].ch)) {
540 prev_char_s = curr_char_s;
541 curr_char_s = sst[curr_char_s].other_next_s;
542 }
543
544 /*
545 * Check if a previously seen keyword has the same prefix as
546 * the current keyword. If so, simply use the state for that
547 * keyword as my_state, otherwise, allocate a new state.
548 */
549 if (curr_char_s && (text[0] == sst[curr_char_s].ch)) {
550 my_state = curr_char_s;
551 if ('\0' == text[1]) {
552 fprintf(stderr,
553 "Duplicate entries for keyword '%s' in"
554 " keyword_gen.c ntp_keywords[].\n",
555 current_keyword);
556 exit(2);
557 }
558 } else {
559 do
560 my_state = sst_highwater++;
561 while (my_state < COUNTOF(sst)
562 && sst[my_state].finishes_token);
563 if (my_state >= COUNTOF(sst)) {
564 fprintf(stderr,
565 "fatal, keyword scanner state array "
566 "sst[%d] is too small, modify\n"
567 "keyword-gen.c to increase.\n",
568 (int)COUNTOF(sst));
569 exit(3);
570 }
571 /* Store the next character of the keyword */
572 sst[my_state].ch = text[0];
573 sst[my_state].other_next_s = curr_char_s;
574 sst[my_state].followedby = FOLLBY_NON_ACCEPTING;
575
576 if (prev_char_s)
577 sst[prev_char_s].other_next_s = my_state;
578 else
579 return_state = my_state;
580 }
581
582 /* Check if the next character is '\0'.
583 * If yes, we are done with the recognition and this is an accepting
584 * state.
585 * If not, we need to continue scanning
586 */
587 if ('\0' == text[1]) {
588 sst[my_state].finishes_token = (u_short)token;
589 sst[my_state].followedby = (char)followedby;
590
591 if (sst[token].finishes_token != (u_short)token) {
592 fprintf(stderr,
593 "fatal, sst[%d] not reserved for %s.\n",
594 token, symbname(token));
595 exit(6);
596 }
597 /* relocate so token id is sst[] index */
598 if (my_state != token) {
599 sst[token] = sst[my_state];
600 ZERO(sst[my_state]);
601 do
602 sst_highwater--;
603 while (sst[sst_highwater].finishes_token);
604 my_state = token;
605 if (prev_char_s)
606 sst[prev_char_s].other_next_s = my_state;
607 else
608 return_state = my_state;
609 }
610 } else
611 sst[my_state].match_next_s =
612 create_scan_states(
613 &text[1],
614 token,
615 followedby,
616 sst[my_state].match_next_s);
617
618 return return_state;
619 }
620
621
622 /* Define a function that takes a list of (keyword, token) values and
623 * creates a keywords scanner out of it.
624 */
625
626 static u_short
create_keyword_scanner(void)627 create_keyword_scanner(void)
628 {
629 u_short scanner;
630 u_short i;
631
632 sst_highwater = 1; /* index 0 invalid, unused */
633 scanner = 0;
634
635 for (i = 0; i < COUNTOF(ntp_keywords); i++) {
636 current_keyword = ntp_keywords[i].key;
637 scanner =
638 create_scan_states(
639 ntp_keywords[i].key,
640 ntp_keywords[i].token,
641 ntp_keywords[i].followedby,
642 scanner);
643 }
644
645 return scanner;
646 }
647
648
649 static void
generate_token_text(void)650 generate_token_text(void)
651 {
652 u_short lowest_id;
653 u_short highest_id;
654 u_short id_count;
655 u_short id;
656 u_short i;
657
658 /* sort ntp_keywords in token ID order */
659 qsort(ntp_keywords, COUNTOF(ntp_keywords),
660 sizeof(ntp_keywords[0]), compare_key_tok_id);
661
662 lowest_id = ntp_keywords[0].token;
663 highest_id = ntp_keywords[COUNTOF(ntp_keywords) - 1].token;
664 id_count = highest_id - lowest_id + 1;
665
666 printf("#define LOWEST_KEYWORD_ID %d\n\n", lowest_id);
667
668 printf("const char * const keyword_text[%d] = {", id_count);
669
670 id = lowest_id;
671 i = 0;
672 while (i < COUNTOF(ntp_keywords)) {
673 while (id < ntp_keywords[i].token) {
674 printf(",\n\t/* %-5d %5d %20s */\tNULL",
675 id - lowest_id, id, symbname(id));
676 id++;
677 }
678 if (i > 0)
679 printf(",");
680 printf("\n\t/* %-5d %5d %20s */\t\"%s\"",
681 id - lowest_id, id, symbname(id),
682 ntp_keywords[i].key);
683 i++;
684 id++;
685 }
686
687 printf("\n};\n\n");
688 }
689
690
691 int
compare_key_tok_id(const void * a1,const void * a2)692 compare_key_tok_id(
693 const void *a1,
694 const void *a2
695 )
696 {
697 const struct key_tok *p1 = a1;
698 const struct key_tok *p2 = a2;
699
700 if (p1->token == p2->token)
701 return 0;
702
703 if (p1->token < p2->token)
704 return -1;
705 else
706 return 1;
707 }
708
709
710 int
compare_key_tok_text(const void * a1,const void * a2)711 compare_key_tok_text(
712 const void *a1,
713 const void *a2
714 )
715 {
716 const struct key_tok *p1 = a1;
717 const struct key_tok *p2 = a2;
718
719 return strcmp(p1->key, p2->key);
720 }
721
722
723 /*
724 * populate_symb() - populate symb[] lookup array with symbolic token
725 * names such that symb[T_Age] == "T_Age", etc.
726 */
727 void
populate_symb(char * header_file)728 populate_symb(
729 char *header_file
730 )
731 {
732 FILE * yh;
733 char line[2 * MAX_TOK_LEN];
734 char name[2 * MAX_TOK_LEN];
735 int token;
736
737 yh = fopen(header_file, "r");
738 if (NULL == yh) {
739 perror("unable to open yacc/bison header file");
740 exit(4);
741 }
742
743 while (NULL != fgets(line, sizeof(line), yh))
744 if (2 == sscanf(line, "#define %s %d", name, &token)
745 && 'T' == name[0] && '_' == name[1] && token >= 0
746 && token < COUNTOF(symb)) {
747
748 symb[token] = estrdup(name);
749 if (strlen(name) > MAX_TOK_LEN) {
750 fprintf(stderr,
751 "MAX_TOK_LEN %d too small for '%s'\n"
752 "Edit keyword-gen.c to raise.\n",
753 MAX_TOK_LEN, name);
754 exit(10);
755 }
756 }
757 fclose(yh);
758 }
759
760
761 const char *
symbname(u_short token)762 symbname(
763 u_short token
764 )
765 {
766 char *name;
767
768 if (token < COUNTOF(symb) && symb[token] != NULL) {
769 name = symb[token];
770 } else {
771 LIB_GETBUF(name);
772 snprintf(name, LIB_BUFLENGTH, "%d", token);
773 }
774
775 return name;
776 }
777