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149#include <string.h>
150#include <ddb/db_lex.h>
151#include <ddb/db_command.h>
152#include <ddb/db_input.h>
153#include <ddb/db_output.h>
154
155char db_line[DB_LEX_LINE_SIZE];
156char db_last_line[DB_LEX_LINE_SIZE];
157char *db_lp, *db_endlp;
158char *db_last_lp;
159int db_look_char = 0;
160db_expr_t db_look_token = 0;
161
162
163
164
165void db_flush_line(void);
166void db_unread_char(int c);
167
168
169int
170db_read_line(char *repeat_last)
171{
172 int i;
173
174 i = db_readline(db_line, sizeof(db_line));
175 if (i == 0)
176 return (0);
177 if (repeat_last) {
178 if (strncmp(db_line, repeat_last, strlen(repeat_last)) == 0) {
179 strcpy(db_line, db_last_line);
180 db_printf("%s", db_line);
181 i = strlen(db_line);
182 } else if (db_line[0] != '\n' && db_line[0] != 0)
183 strcpy(db_last_line, db_line);
184 }
185 db_lp = db_line;
186 db_endlp = db_lp + i;
187 db_last_lp = db_lp;
188 db_look_char = 0;
189 db_look_token = 0;
190 return (i);
191}
192
193void
194db_flush_line(void)
195{
196 db_lp = db_line;
197 db_last_lp = db_lp;
198 db_endlp = db_line;
199}
200
201void
202db_switch_input(
203 char *buffer,
204 int size)
205{
206 db_lp = buffer;
207 db_last_lp = db_lp;
208 db_endlp = buffer + size;
209 db_look_char = 0;
210 db_look_token = 0;
211}
212
213void
214db_save_lex_context(register struct db_lex_context *lp)
215{
216 lp->l_ptr = db_lp;
217 lp->l_eptr = db_endlp;
218 lp->l_char = db_look_char;
219 lp->l_token = db_look_token;
220}
221
222void
223db_restore_lex_context(register struct db_lex_context *lp)
224{
225 db_lp = lp->l_ptr;
226 db_last_lp = db_lp;
227 db_endlp = lp->l_eptr;
228 db_look_char = lp->l_char;
229 db_look_token = lp->l_token;
230}
231
232int
233db_read_char(void)
234{
235 int c;
236
237 if (db_look_char != 0) {
238 c = db_look_char;
239 db_look_char = 0;
240 }
241 else if (db_lp >= db_endlp)
242 c = -1;
243 else
244 c = *db_lp++;
245 return (c);
246}
247
248void
249db_unread_char(int c)
250{
251 db_look_char = c;
252}
253
254void
255db_unread_token(int t)
256{
257 db_look_token = t;
258}
259
260int
261db_read_token(void)
262{
263 int t;
264
265 if (db_look_token) {
266 t = db_look_token;
267 db_look_token = 0;
268 }
269 else {
270 db_last_lp = db_lp;
271 if (db_look_char)
272 db_last_lp--;
273 t = db_lex();
274 }
275 return (t);
276}
277
278db_expr_t db_tok_number;
279char db_tok_string[TOK_STRING_SIZE];
280
281db_expr_t db_radix = 16;
282
283void
284db_flush_lex(void)
285{
286 db_flush_line();
287 db_look_char = 0;
288 db_look_token = 0;
289}
290
291#define DB_DISP_SKIP 40
292
293void
294db_skip_to_eol(void)
295{
296 register int skip;
297 register int t;
298 register int n;
299 register char *p;
300
301 t = db_read_token();
302 p = db_last_lp;
303 for (skip = 0; t != tEOL && t != tSEMI_COLON && t != tEOF; skip++)
304 t = db_read_token();
305 if (t == tSEMI_COLON)
306 db_unread_token(t);
307 if (skip != 0) {
308 while (p < db_last_lp && (*p == ' ' || *p == '\t'))
309 p++;
310 db_printf("Warning: Skipped input data \"");
311 for (n = 0; n < DB_DISP_SKIP && p < db_last_lp; n++)
312 db_printf("%c", *p++);
313 if (n >= DB_DISP_SKIP)
314 db_printf("....");
315 db_printf("\"\n");
316 }
317}
318
319int
320db_lex(void)
321{
322 register char *cp;
323 register int c;
324
325 c = db_read_char();
326 while (c <= ' ' || c > '~') {
327 if (c == '\n' || c == -1)
328 return (tEOL);
329 c = db_read_char();
330 }
331
332 cp = db_tok_string;
333 *cp++ = c;
334
335 if (c >= '0' && c <= '9') {
336
337 int r, digit;
338
339 if (c > '0')
340 r = db_radix;
341 else {
342 c = db_read_char();
343 if (c == 'O' || c == 'o')
344 r = 8;
345 else if (c == 'T' || c == 't')
346 r = 10;
347 else if (c == 'X' || c == 'x')
348 r = 16;
349 else {
350 cp--;
351 r = db_radix;
352 db_unread_char(c);
353 }
354 c = db_read_char();
355 *cp++ = c;
356 }
357 db_tok_number = 0;
358 for (;;) {
359 if (c >= '0' && c <= ((r == 8) ? '7' : '9'))
360 digit = c - '0';
361 else if (r == 16 && ((c >= 'A' && c <= 'F') ||
362 (c >= 'a' && c <= 'f'))) {
363 if (c >= 'a')
364 digit = c - 'a' + 10;
365 else
366 digit = c - 'A' + 10;
367 }
368 else
369 break;
370 db_tok_number = db_tok_number * r + digit;
371 c = db_read_char();
372 if (cp < &db_tok_string[sizeof(db_tok_string)-1])
373 *cp++ = c;
374 }
375 cp[-1] = 0;
376 if ((c >= '0' && c <= '9') ||
377 (c >= 'A' && c <= 'Z') ||
378 (c >= 'a' && c <= 'z') ||
379 (c == '_'))
380 {
381 db_printf("Bad character '%c' after number %s\n",
382 c, db_tok_string);
383 db_error(0);
384 db_flush_lex();
385 return (tEOF);
386 }
387 db_unread_char(c);
388 return (tNUMBER);
389 }
390 if ((c >= 'A' && c <= 'Z') ||
391 (c >= 'a' && c <= 'z') ||
392 c == '_' || c == '\\' || c == ':')
393 {
394
395 if (c == '\\') {
396 c = db_read_char();
397 if (c == '\n' || c == -1)
398 db_error("Bad '\\' at the end of line\n");
399 cp[-1] = c;
400 }
401 while (1) {
402 c = db_read_char();
403 if ((c >= 'A' && c <= 'Z') ||
404 (c >= 'a' && c <= 'z') ||
405 (c >= '0' && c <= '9') ||
406 c == '_' || c == '\\' || c == ':' || c == '.')
407 {
408 if (c == '\\') {
409 c = db_read_char();
410 if (c == '\n' || c == -1)
411 db_error("Bad '\\' at the end of line\n");
412 }
413 *cp++ = c;
414 if (cp == db_tok_string+sizeof(db_tok_string)) {
415 db_error("String too long\n");
416 db_flush_lex();
417 return (tEOF);
418 }
419 continue;
420 }
421 else {
422 *cp = '\0';
423 break;
424 }
425 }
426 db_unread_char(c);
427 return (tIDENT);
428 }
429
430 *cp = 0;
431 switch (c) {
432 case '+':
433 return (tPLUS);
434 case '-':
435 return (tMINUS);
436 case '.':
437 c = db_read_char();
438 if (c == '.') {
439 *cp++ = c;
440 *cp = 0;
441 return (tDOTDOT);
442 }
443 db_unread_char(c);
444 return (tDOT);
445 case '*':
446 return (tSTAR);
447 case '/':
448 return (tSLASH);
449 case '=':
450 c = db_read_char();
451 if (c == '=') {
452 *cp++ = c;
453 *cp = 0;
454 return(tLOG_EQ);
455 }
456 db_unread_char(c);
457 return (tEQ);
458 case '%':
459 return (tPCT);
460 case '#':
461 return (tHASH);
462 case '(':
463 return (tLPAREN);
464 case ')':
465 return (tRPAREN);
466 case ',':
467 return (tCOMMA);
468 case '\'':
469 return (tQUOTE);
470 case '"':
471
472 cp = db_tok_string;
473 c = db_read_char();
474 while (c != '"' && c > 0 && c != '\n') {
475 if (cp >= &db_tok_string[sizeof(db_tok_string)-1]) {
476 db_error("Too long string\n");
477 db_flush_lex();
478 return (tEOF);
479 }
480 if (c == '\\') {
481 c = db_read_char();
482 switch(c) {
483 case 'n':
484 c = '\n'; break;
485 case 't':
486 c = '\t'; break;
487 case '\\':
488 case '"':
489 break;
490 default:
491 db_printf("Bad escape sequence '\\%c'\n", c);
492 db_error(0);
493 db_flush_lex();
494 return (tEOF);
495 }
496 }
497 *cp++ = c;
498 c = db_read_char();
499 }
500 *cp = 0;
501 if (c != '"') {
502 db_error("Non terminated string constant\n");
503 db_flush_lex();
504 return (tEOF);
505 }
506 return (tSTRING);
507 case '$':
508 return (tDOLLAR);
509 case '!':
510 c = db_read_char();
511 if (c == '=') {
512 *cp++ = c;
513 *cp = 0;
514 return(tLOG_NOT_EQ);
515 }
516 db_unread_char(c);
517 return (tEXCL);
518 case '&':
519 c = db_read_char();
520 if (c == '&') {
521 *cp++ = c;
522 *cp = 0;
523 return(tLOG_AND);
524 }
525 db_unread_char(c);
526 return(tBIT_AND);
527 case '|':
528 c = db_read_char();
529 if (c == '|') {
530 *cp++ = c;
531 *cp = 0;
532 return(tLOG_OR);
533 }
534 db_unread_char(c);
535 return(tBIT_OR);
536 case '<':
537 c = db_read_char();
538 *cp++ = c;
539 *cp = 0;
540 if (c == '<')
541 return (tSHIFT_L);
542 if (c == '=')
543 return (tLESS_EQ);
544 cp[-1] = 0;
545 db_unread_char(c);
546 return(tLESS);
547 break;
548 case '>':
549 c = db_read_char();
550 *cp++ = c;
551 *cp = 0;
552 if (c == '>')
553 return (tSHIFT_R);
554 if (c == '=')
555 return (tGREATER_EQ);
556 cp[-1] = 0;
557 db_unread_char(c);
558 return (tGREATER);
559 break;
560 case ';':
561 return (tSEMI_COLON);
562 case '?':
563 return (tQUESTION);
564 case -1:
565 strcpy(db_tok_string, "<EOL>");
566 return (tEOF);
567 }
568 db_printf("Bad character '%c'\n", c);
569 db_flush_lex();
570 return (tEOF);
571}
572
