xref: /freebsd/contrib/flex/src/misc.c (revision cc68614da8232d8baaca0ae0d0dd8f890f06623e)
1 /* misc - miscellaneous flex routines */
2 
3 /*  Copyright (c) 1990 The Regents of the University of California. */
4 /*  All rights reserved. */
5 
6 /*  This code is derived from software contributed to Berkeley by */
7 /*  Vern Paxson. */
8 
9 /*  The United States Government has rights in this work pursuant */
10 /*  to contract no. DE-AC03-76SF00098 between the United States */
11 /*  Department of Energy and the University of California. */
12 
13 /*  This file is part of flex. */
14 
15 /*  Redistribution and use in source and binary forms, with or without */
16 /*  modification, are permitted provided that the following conditions */
17 /*  are met: */
18 
19 /*  1. Redistributions of source code must retain the above copyright */
20 /*     notice, this list of conditions and the following disclaimer. */
21 /*  2. Redistributions in binary form must reproduce the above copyright */
22 /*     notice, this list of conditions and the following disclaimer in the */
23 /*     documentation and/or other materials provided with the distribution. */
24 
25 /*  Neither the name of the University nor the names of its contributors */
26 /*  may be used to endorse or promote products derived from this software */
27 /*  without specific prior written permission. */
28 
29 /*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR */
30 /*  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED */
31 /*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR */
32 /*  PURPOSE. */
33 #include "flexdef.h"
34 #include "tables.h"
35 
36 #define CMD_IF_TABLES_SER    "%if-tables-serialization"
37 #define CMD_TABLES_YYDMAP    "%tables-yydmap"
38 #define CMD_DEFINE_YYTABLES  "%define-yytables"
39 #define CMD_IF_CPP_ONLY      "%if-c++-only"
40 #define CMD_IF_C_ONLY        "%if-c-only"
41 #define CMD_IF_C_OR_CPP      "%if-c-or-c++"
42 #define CMD_NOT_FOR_HEADER   "%not-for-header"
43 #define CMD_OK_FOR_HEADER    "%ok-for-header"
44 #define CMD_PUSH             "%push"
45 #define CMD_POP              "%pop"
46 #define CMD_IF_REENTRANT     "%if-reentrant"
47 #define CMD_IF_NOT_REENTRANT "%if-not-reentrant"
48 #define CMD_IF_BISON_BRIDGE  "%if-bison-bridge"
49 #define CMD_IF_NOT_BISON_BRIDGE  "%if-not-bison-bridge"
50 #define CMD_ENDIF            "%endif"
51 
52 /* we allow the skeleton to push and pop. */
53 struct sko_state {
54     bool dc; /**< do_copy */
55 };
56 static struct sko_state *sko_stack=0;
57 static int sko_len=0,sko_sz=0;
58 static void sko_push(bool dc)
59 {
60     if(!sko_stack){
61         sko_sz = 1;
62         sko_stack = malloc(sizeof(struct sko_state) * (size_t) sko_sz);
63         if (!sko_stack)
64             flexfatal(_("allocation of sko_stack failed"));
65         sko_len = 0;
66     }
67     if(sko_len >= sko_sz){
68         sko_sz *= 2;
69         sko_stack = realloc(sko_stack,
70 			sizeof(struct sko_state) * (size_t) sko_sz);
71     }
72 
73     /* initialize to zero and push */
74     sko_stack[sko_len].dc = dc;
75     sko_len++;
76 }
77 static void sko_peek(bool *dc)
78 {
79     if(sko_len <= 0)
80         flex_die("peek attempt when sko stack is empty");
81     if(dc)
82         *dc = sko_stack[sko_len-1].dc;
83 }
84 static void sko_pop(bool* dc)
85 {
86     sko_peek(dc);
87     sko_len--;
88     if(sko_len < 0)
89         flex_die("popped too many times in skeleton.");
90 }
91 
92 /* Append "#define defname value\n" to the running buffer. */
93 void action_define (const char *defname, int value)
94 {
95 	char    buf[MAXLINE];
96 	char   *cpy;
97 
98 	if ((int) strlen (defname) > MAXLINE / 2) {
99 		format_pinpoint_message (_
100 					 ("name \"%s\" ridiculously long"),
101 					 defname);
102 		return;
103 	}
104 
105 	snprintf (buf, sizeof(buf), "#define %s %d\n", defname, value);
106 	add_action (buf);
107 
108 	/* track #defines so we can undef them when we're done. */
109 	cpy = xstrdup(defname);
110 	buf_append (&defs_buf, &cpy, 1);
111 }
112 
113 /* Append "new_text" to the running buffer. */
114 void add_action (const char *new_text)
115 {
116 	int     len = (int) strlen (new_text);
117 
118 	while (len + action_index >= action_size - 10 /* slop */ ) {
119 		int     new_size = action_size * 2;
120 
121 		if (new_size <= 0)
122 			/* Increase just a little, to try to avoid overflow
123 			 * on 16-bit machines.
124 			 */
125 			action_size += action_size / 8;
126 		else
127 			action_size = new_size;
128 
129 		action_array =
130 			reallocate_character_array (action_array,
131 						    action_size);
132 	}
133 
134 	strcpy (&action_array[action_index], new_text);
135 
136 	action_index += len;
137 }
138 
139 
140 /* allocate_array - allocate memory for an integer array of the given size */
141 
142 void   *allocate_array (int size, size_t element_size)
143 {
144 	void *mem;
145 #if HAVE_REALLOCARRAY
146 	/* reallocarray has built-in overflow detection */
147 	mem = reallocarray(NULL, (size_t) size, element_size);
148 #else
149 	size_t num_bytes = (size_t) size * element_size;
150 	mem = (size && SIZE_MAX / (size_t) size < element_size) ? NULL :
151 		malloc(num_bytes);
152 #endif
153 	if (!mem)
154 		flexfatal (_
155 			   ("memory allocation failed in allocate_array()"));
156 
157 	return mem;
158 }
159 
160 
161 /* all_lower - true if a string is all lower-case */
162 
163 int all_lower (char *str)
164 {
165 	while (*str) {
166 		if (!isascii ((unsigned char) * str) || !islower ((unsigned char) * str))
167 			return 0;
168 		++str;
169 	}
170 
171 	return 1;
172 }
173 
174 
175 /* all_upper - true if a string is all upper-case */
176 
177 int all_upper (char *str)
178 {
179 	while (*str) {
180 		if (!isascii ((unsigned char) * str) || !isupper ((unsigned char) * str))
181 			return 0;
182 		++str;
183 	}
184 
185 	return 1;
186 }
187 
188 
189 /* intcmp - compares two integers for use by qsort. */
190 
191 int intcmp (const void *a, const void *b)
192 {
193   return *(const int *) a - *(const int *) b;
194 }
195 
196 
197 /* check_char - checks a character to make sure it's within the range
198  *		we're expecting.  If not, generates fatal error message
199  *		and exits.
200  */
201 
202 void check_char (int c)
203 {
204 	if (c >= CSIZE)
205 		lerr (_("bad character '%s' detected in check_char()"),
206 			readable_form (c));
207 
208 	if (c >= csize)
209 		lerr (_
210 			("scanner requires -8 flag to use the character %s"),
211 			readable_form (c));
212 }
213 
214 
215 
216 /* clower - replace upper-case letter to lower-case */
217 
218 unsigned char clower (int c)
219 {
220 	return (unsigned char) ((isascii (c) && isupper (c)) ? tolower (c) : c);
221 }
222 
223 
224 char *xstrdup(const char *s)
225 {
226 	char *s2;
227 
228 	if ((s2 = strdup(s)) == NULL)
229 		flexfatal (_("memory allocation failure in xstrdup()"));
230 
231 	return s2;
232 }
233 
234 
235 /* cclcmp - compares two characters for use by qsort with '\0' sorting last. */
236 
237 int cclcmp (const void *a, const void *b)
238 {
239   if (!*(const unsigned char *) a)
240 	return 1;
241   else
242 	if (!*(const unsigned char *) b)
243 	  return - 1;
244 	else
245 	  return *(const unsigned char *) a - *(const unsigned char *) b;
246 }
247 
248 
249 /* dataend - finish up a block of data declarations */
250 
251 void dataend (void)
252 {
253 	/* short circuit any output */
254 	if (gentables) {
255 
256 		if (datapos > 0)
257 			dataflush ();
258 
259 		/* add terminator for initialization; { for vi */
260 		outn ("    } ;\n");
261 	}
262 	dataline = 0;
263 	datapos = 0;
264 }
265 
266 
267 /* dataflush - flush generated data statements */
268 
269 void dataflush (void)
270 {
271 	/* short circuit any output */
272 	if (!gentables)
273 		return;
274 
275 	outc ('\n');
276 
277 	if (++dataline >= NUMDATALINES) {
278 		/* Put out a blank line so that the table is grouped into
279 		 * large blocks that enable the user to find elements easily.
280 		 */
281 		outc ('\n');
282 		dataline = 0;
283 	}
284 
285 	/* Reset the number of characters written on the current line. */
286 	datapos = 0;
287 }
288 
289 
290 /* flexerror - report an error message and terminate */
291 
292 void flexerror (const char *msg)
293 {
294 	fprintf (stderr, "%s: %s\n", program_name, msg);
295 	flexend (1);
296 }
297 
298 
299 /* flexfatal - report a fatal error message and terminate */
300 
301 void flexfatal (const char *msg)
302 {
303 	fprintf (stderr, _("%s: fatal internal error, %s\n"),
304 		 program_name, msg);
305 	FLEX_EXIT (1);
306 }
307 
308 
309 /* lerr - report an error message */
310 
311 void lerr (const char *msg, ...)
312 {
313 	char    errmsg[MAXLINE];
314 	va_list args;
315 
316 	va_start(args, msg);
317 	vsnprintf (errmsg, sizeof(errmsg), msg, args);
318 	va_end(args);
319 	flexerror (errmsg);
320 }
321 
322 
323 /* lerr_fatal - as lerr, but call flexfatal */
324 
325 void lerr_fatal (const char *msg, ...)
326 {
327 	char    errmsg[MAXLINE];
328 	va_list args;
329 	va_start(args, msg);
330 
331 	vsnprintf (errmsg, sizeof(errmsg), msg, args);
332 	va_end(args);
333 	flexfatal (errmsg);
334 }
335 
336 
337 /* line_directive_out - spit out a "#line" statement */
338 
339 void line_directive_out (FILE *output_file, int do_infile)
340 {
341 	char    directive[MAXLINE], filename[MAXLINE];
342 	char   *s1, *s2, *s3;
343 	static const char line_fmt[] = "#line %d \"%s\"\n";
344 
345 	if (!gen_line_dirs)
346 		return;
347 
348 	s1 = do_infile ? infilename : "M4_YY_OUTFILE_NAME";
349 
350 	if (do_infile && !s1)
351         s1 = "<stdin>";
352 
353 	s2 = filename;
354 	s3 = &filename[sizeof (filename) - 2];
355 
356 	while (s2 < s3 && *s1) {
357 		if (*s1 == '\\' || *s1 == '"')
358 			/* Escape the '\' or '"' */
359 			*s2++ = '\\';
360 
361 		*s2++ = *s1++;
362 	}
363 
364 	*s2 = '\0';
365 
366 	if (do_infile)
367 		snprintf (directive, sizeof(directive), line_fmt, linenum, filename);
368 	else {
369 		snprintf (directive, sizeof(directive), line_fmt, 0, filename);
370 	}
371 
372 	/* If output_file is nil then we should put the directive in
373 	 * the accumulated actions.
374 	 */
375 	if (output_file) {
376 		fputs (directive, output_file);
377 	}
378 	else
379 		add_action (directive);
380 }
381 
382 
383 /* mark_defs1 - mark the current position in the action array as
384  *               representing where the user's section 1 definitions end
385  *		 and the prolog begins
386  */
387 void mark_defs1 (void)
388 {
389 	defs1_offset = 0;
390 	action_array[action_index++] = '\0';
391 	action_offset = prolog_offset = action_index;
392 	action_array[action_index] = '\0';
393 }
394 
395 
396 /* mark_prolog - mark the current position in the action array as
397  *               representing the end of the action prolog
398  */
399 void mark_prolog (void)
400 {
401 	action_array[action_index++] = '\0';
402 	action_offset = action_index;
403 	action_array[action_index] = '\0';
404 }
405 
406 
407 /* mk2data - generate a data statement for a two-dimensional array
408  *
409  * Generates a data statement initializing the current 2-D array to "value".
410  */
411 void mk2data (int value)
412 {
413 	/* short circuit any output */
414 	if (!gentables)
415 		return;
416 
417 	if (datapos >= NUMDATAITEMS) {
418 		outc (',');
419 		dataflush ();
420 	}
421 
422 	if (datapos == 0)
423 		/* Indent. */
424 		out ("    ");
425 
426 	else
427 		outc (',');
428 
429 	++datapos;
430 
431 	out_dec ("%5d", value);
432 }
433 
434 
435 /* mkdata - generate a data statement
436  *
437  * Generates a data statement initializing the current array element to
438  * "value".
439  */
440 void mkdata (int value)
441 {
442 	/* short circuit any output */
443 	if (!gentables)
444 		return;
445 
446 	if (datapos >= NUMDATAITEMS) {
447 		outc (',');
448 		dataflush ();
449 	}
450 
451 	if (datapos == 0)
452 		/* Indent. */
453 		out ("    ");
454 	else
455 		outc (',');
456 
457 	++datapos;
458 
459 	out_dec ("%5d", value);
460 }
461 
462 
463 /* myctoi - return the integer represented by a string of digits */
464 
465 int myctoi (const char *array)
466 {
467 	int     val = 0;
468 
469 	(void) sscanf (array, "%d", &val);
470 
471 	return val;
472 }
473 
474 
475 /* myesc - return character corresponding to escape sequence */
476 
477 unsigned char myesc (unsigned char array[])
478 {
479 	unsigned char    c, esc_char;
480 
481 	switch (array[1]) {
482 	case 'b':
483 		return '\b';
484 	case 'f':
485 		return '\f';
486 	case 'n':
487 		return '\n';
488 	case 'r':
489 		return '\r';
490 	case 't':
491 		return '\t';
492 	case 'a':
493 		return '\a';
494 	case 'v':
495 		return '\v';
496 	case '0':
497 	case '1':
498 	case '2':
499 	case '3':
500 	case '4':
501 	case '5':
502 	case '6':
503 	case '7':
504 		{		/* \<octal> */
505 			int     sptr = 1;
506 
507 			while (sptr <= 3 &&
508                                array[sptr] >= '0' && array[sptr] <= '7') {
509 				++sptr;
510 			}
511 
512 			c = array[sptr];
513 			array[sptr] = '\0';
514 
515 			esc_char = (unsigned char) strtoul (array + 1, NULL, 8);
516 
517 			array[sptr] = c;
518 
519 			return esc_char;
520 		}
521 
522 	case 'x':
523 		{		/* \x<hex> */
524 			int     sptr = 2;
525 
526 			while (sptr <= 3 && isxdigit (array[sptr])) {
527 				/* Don't increment inside loop control
528 				 * because if isxdigit() is a macro it might
529 				 * expand into multiple increments ...
530 				 */
531 				++sptr;
532 			}
533 
534 			c = array[sptr];
535 			array[sptr] = '\0';
536 
537 			esc_char = (unsigned char) strtoul (array + 2, NULL, 16);
538 
539 			array[sptr] = c;
540 
541 			return esc_char;
542 		}
543 
544 	default:
545 		return array[1];
546 	}
547 }
548 
549 
550 /* out - various flavors of outputing a (possibly formatted) string for the
551  *	 generated scanner, keeping track of the line count.
552  */
553 
554 void out (const char *str)
555 {
556 	fputs (str, stdout);
557 }
558 
559 void out_dec (const char *fmt, int n)
560 {
561 	fprintf (stdout, fmt, n);
562 }
563 
564 void out_dec2 (const char *fmt, int n1, int n2)
565 {
566 	fprintf (stdout, fmt, n1, n2);
567 }
568 
569 void out_hex (const char *fmt, unsigned int x)
570 {
571 	fprintf (stdout, fmt, x);
572 }
573 
574 void out_str (const char *fmt, const char str[])
575 {
576 	fprintf (stdout,fmt, str);
577 }
578 
579 void out_str3 (const char *fmt, const char s1[], const char s2[], const char s3[])
580 {
581 	fprintf (stdout,fmt, s1, s2, s3);
582 }
583 
584 void out_str_dec (const char *fmt, const char str[], int n)
585 {
586 	fprintf (stdout,fmt, str, n);
587 }
588 
589 void outc (int c)
590 {
591 	fputc (c, stdout);
592 }
593 
594 void outn (const char *str)
595 {
596 	fputs (str,stdout);
597     fputc('\n',stdout);
598 }
599 
600 /** Print "m4_define( [[def]], [[val]])m4_dnl\n".
601  * @param def The m4 symbol to define.
602  * @param val The definition; may be NULL.
603  */
604 void out_m4_define (const char* def, const char* val)
605 {
606     const char * fmt = "m4_define( [[%s]], [[%s]])m4_dnl\n";
607     fprintf(stdout, fmt, def, val?val:"");
608 }
609 
610 
611 /* readable_form - return the the human-readable form of a character
612  *
613  * The returned string is in static storage.
614  */
615 
616 char   *readable_form (int c)
617 {
618 	static char rform[20];
619 
620 	if ((c >= 0 && c < 32) || c >= 127) {
621 		switch (c) {
622 		case '\b':
623 			return "\\b";
624 		case '\f':
625 			return "\\f";
626 		case '\n':
627 			return "\\n";
628 		case '\r':
629 			return "\\r";
630 		case '\t':
631 			return "\\t";
632 		case '\a':
633 			return "\\a";
634 		case '\v':
635 			return "\\v";
636 		default:
637 			if(trace_hex)
638 				snprintf (rform, sizeof(rform), "\\x%.2x", (unsigned int) c);
639 			else
640 				snprintf (rform, sizeof(rform), "\\%.3o", (unsigned int) c);
641 			return rform;
642 		}
643 	}
644 
645 	else if (c == ' ')
646 		return "' '";
647 
648 	else {
649 		rform[0] = (char) c;
650 		rform[1] = '\0';
651 
652 		return rform;
653 	}
654 }
655 
656 
657 /* reallocate_array - increase the size of a dynamic array */
658 
659 void   *reallocate_array (void *array, int size, size_t element_size)
660 {
661 	void *new_array;
662 #if HAVE_REALLOCARRAY
663 	/* reallocarray has built-in overflow detection */
664 	new_array = reallocarray(array, (size_t) size, element_size);
665 #else
666 	size_t num_bytes = (size_t) size * element_size;
667 	new_array = (size && SIZE_MAX / (size_t) size < element_size) ? NULL :
668 		realloc(array, num_bytes);
669 #endif
670 	if (!new_array)
671 		flexfatal (_("attempt to increase array size failed"));
672 
673 	return new_array;
674 }
675 
676 
677 /* skelout - write out one section of the skeleton file
678  *
679  * Description
680  *    Copies skelfile or skel array to stdout until a line beginning with
681  *    "%%" or EOF is found.
682  */
683 void skelout (void)
684 {
685 	char    buf_storage[MAXLINE];
686 	char   *buf = buf_storage;
687 	bool   do_copy = true;
688 
689     /* "reset" the state by clearing the buffer and pushing a '1' */
690     if(sko_len > 0)
691         sko_peek(&do_copy);
692     sko_len = 0;
693     sko_push(do_copy=true);
694 
695 
696 	/* Loop pulling lines either from the skelfile, if we're using
697 	 * one, or from the skel[] array.
698 	 */
699 	while (skelfile ?
700 	       (fgets (buf, MAXLINE, skelfile) != NULL) :
701 	       ((buf = (char *) skel[skel_ind++]) != 0)) {
702 
703 		if (skelfile)
704 			chomp (buf);
705 
706 		/* copy from skel array */
707 		if (buf[0] == '%') {	/* control line */
708 			/* print the control line as a comment. */
709 			if (ddebug && buf[1] != '#') {
710 				if (buf[strlen (buf) - 1] == '\\')
711 					out_str ("/* %s */\\\n", buf);
712 				else
713 					out_str ("/* %s */\n", buf);
714 			}
715 
716 			/* We've been accused of using cryptic markers in the skel.
717 			 * So we'll use emacs-style-hyphenated-commands.
718              * We might consider a hash if this if-else-if-else
719              * chain gets too large.
720 			 */
721 #define cmd_match(s) (strncmp(buf,(s),strlen(s))==0)
722 
723 			if (buf[1] == '%') {
724 				/* %% is a break point for skelout() */
725 				return;
726 			}
727             else if (cmd_match (CMD_PUSH)){
728                 sko_push(do_copy);
729                 if(ddebug){
730                     out_str("/*(state = (%s) */",do_copy?"true":"false");
731                 }
732                 out_str("%s\n", buf[strlen (buf) - 1] =='\\' ? "\\" : "");
733             }
734             else if (cmd_match (CMD_POP)){
735                 sko_pop(&do_copy);
736                 if(ddebug){
737                     out_str("/*(state = (%s) */",do_copy?"true":"false");
738                 }
739                 out_str("%s\n", buf[strlen (buf) - 1] =='\\' ? "\\" : "");
740             }
741             else if (cmd_match (CMD_IF_REENTRANT)){
742                 sko_push(do_copy);
743                 do_copy = reentrant && do_copy;
744             }
745             else if (cmd_match (CMD_IF_NOT_REENTRANT)){
746                 sko_push(do_copy);
747                 do_copy = !reentrant && do_copy;
748             }
749             else if (cmd_match(CMD_IF_BISON_BRIDGE)){
750                 sko_push(do_copy);
751                 do_copy = bison_bridge_lval && do_copy;
752             }
753             else if (cmd_match(CMD_IF_NOT_BISON_BRIDGE)){
754                 sko_push(do_copy);
755                 do_copy = !bison_bridge_lval && do_copy;
756             }
757             else if (cmd_match (CMD_ENDIF)){
758                 sko_pop(&do_copy);
759             }
760 			else if (cmd_match (CMD_IF_TABLES_SER)) {
761                 do_copy = do_copy && tablesext;
762 			}
763 			else if (cmd_match (CMD_TABLES_YYDMAP)) {
764 				if (tablesext && yydmap_buf.elts)
765 					outn ((char *) (yydmap_buf.elts));
766 			}
767             else if (cmd_match (CMD_DEFINE_YYTABLES)) {
768                 out_str("#define YYTABLES_NAME \"%s\"\n",
769                         tablesname?tablesname:"yytables");
770             }
771 			else if (cmd_match (CMD_IF_CPP_ONLY)) {
772 				/* only for C++ */
773                 sko_push(do_copy);
774 				do_copy = C_plus_plus;
775 			}
776 			else if (cmd_match (CMD_IF_C_ONLY)) {
777 				/* %- only for C */
778                 sko_push(do_copy);
779 				do_copy = !C_plus_plus;
780 			}
781 			else if (cmd_match (CMD_IF_C_OR_CPP)) {
782 				/* %* for C and C++ */
783                 sko_push(do_copy);
784 				do_copy = true;
785 			}
786 			else if (cmd_match (CMD_NOT_FOR_HEADER)) {
787 				/* %c begin linkage-only (non-header) code. */
788 				OUT_BEGIN_CODE ();
789 			}
790 			else if (cmd_match (CMD_OK_FOR_HEADER)) {
791 				/* %e end linkage-only code. */
792 				OUT_END_CODE ();
793 			}
794 			else {
795 				flexfatal (_("bad line in skeleton file"));
796 			}
797 		}
798 
799 		else if (do_copy)
800             outn (buf);
801 	}			/* end while */
802 }
803 
804 
805 /* transition_struct_out - output a yy_trans_info structure
806  *
807  * outputs the yy_trans_info structure with the two elements, element_v and
808  * element_n.  Formats the output with spaces and carriage returns.
809  */
810 
811 void transition_struct_out (int element_v, int element_n)
812 {
813 
814 	/* short circuit any output */
815 	if (!gentables)
816 		return;
817 
818 	out_dec2 (" {%4d,%4d },", element_v, element_n);
819 
820 	datapos += TRANS_STRUCT_PRINT_LENGTH;
821 
822 	if (datapos >= 79 - TRANS_STRUCT_PRINT_LENGTH) {
823 		outc ('\n');
824 
825 		if (++dataline % 10 == 0)
826 			outc ('\n');
827 
828 		datapos = 0;
829 	}
830 }
831 
832 
833 /* The following is only needed when building flex's parser using certain
834  * broken versions of bison.
835  *
836  * XXX: this is should go soon
837  */
838 void   *yy_flex_xmalloc (int size)
839 {
840 	void   *result;
841 
842 	result = malloc((size_t) size);
843 	if (!result)
844 		flexfatal (_
845 			   ("memory allocation failed in yy_flex_xmalloc()"));
846 
847 	return result;
848 }
849 
850 
851 /* Remove all '\n' and '\r' characters, if any, from the end of str.
852  * str can be any null-terminated string, or NULL.
853  * returns str. */
854 char   *chomp (char *str)
855 {
856 	char   *p = str;
857 
858 	if (!str || !*str)	/* s is null or empty string */
859 		return str;
860 
861 	/* find end of string minus one */
862 	while (*p)
863 		++p;
864 	--p;
865 
866 	/* eat newlines */
867 	while (p >= str && (*p == '\r' || *p == '\n'))
868 		*p-- = 0;
869 	return str;
870 }
871