--- /dev/null
+/* Lexer for scanner of bytecode definition file.
+ Copyright (C) 1993 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU CC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU CC; see the file COPYING. If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <stdio.h>
+#include "bi-parser.h"
+
+extern char *malloc ();
+extern char *realloc ();
+
+
+/* Current read buffer and point */
+static char *buffer = NULL;
+static char *inpoint = NULL;
+
+
+/* Safely allocate NBYTES bytes of memory. Reuturns pointer to block of
+ memory. */
+
+static char *
+xmalloc (nbytes)
+ int nbytes;
+{
+ char *tmp = malloc (nbytes);
+
+ if (!tmp)
+ {
+ fprintf (stderr, "can't allocate %d bytes (out of virtual memory)\n", nbytes);
+ exit (1);
+ }
+
+ return tmp;
+}
+
+
+/* Safely reallocate BLOCK so its size becomes NBYTES.
+ The block returned may be different from the one supplied. */
+
+static char *
+xrealloc (block, nbytes)
+ char *block;
+ int nbytes;
+{
+ char *tmp = realloc (block, nbytes);
+
+ if (!tmp)
+ {
+ fprintf (stderr, "can't reallocate %d bytes (out of virtual memory)\n", nbytes);
+ exit (1);
+ }
+
+ return tmp;
+}
+
+
+/* Scan for string token on standard input. A string is, for our
+ purposes here, a sequence of characters that starts with the regexp
+ ``[^ #\t\n(),]'' and is then followed by the regexp ``[^#(),]*''. Any
+ character is accepted if preceded by a backslash, "\\". It is assumed
+ that the first character has already been checked by the main loop. */
+
+static char *
+scan_string ()
+{
+ char *buffer = NULL;
+ char *point = NULL;
+ int buffer_size = 0;
+ int c;
+
+ while ((c = getc (stdin)) != EOF
+ && c != '#' && c != '(' && c != ')' && c != ',')
+ {
+ /* Extend buffer, if necessary (minus two so there's room for the NUL
+ trailer as well as another character if this one is a backslash). */
+ if (!buffer_size || (point - buffer >= buffer_size-2))
+ {
+ int previous_point_index = point - buffer;
+
+ buffer_size = (!buffer_size ? 32 : buffer_size * 2);
+ if (buffer)
+ buffer = xmalloc (buffer_size);
+ else
+ buffer = xrealloc (buffer, buffer_size);
+
+ point = buffer + previous_point_index;
+ }
+ *point++ = c & 0xff;
+
+ if (c == '\\')
+ {
+ c = getc (stdin);
+
+ /* Catch special case: backslash at end of file */
+ if (c == EOF)
+ break;
+
+ *point++ = c;
+ }
+ }
+ *point = 0;
+
+ if (c != EOF)
+ ungetc (c, stdin);
+
+ return buffer;
+}
+
+
+int
+yylex ()
+{
+ int c;
+ char *token;
+
+
+ /* First char determines what token we're looking at */
+ for (;;)
+ {
+ c = getc (stdin);
+
+ switch (c)
+ {
+ case EOF:
+ return 0;
+
+ case ' ':
+ case '\t':
+ case '\n':
+ /* Ignore whitespace */
+ continue;
+
+ case '#':
+ /* Comments advance to next line */
+ while ((c = getc (stdin)) != '\n' && c != EOF);
+ continue;
+
+ default:
+ if (c != '(' && c != ')' && c != '\\' && c != ',')
+ {
+ ungetc (c, stdin);
+ yylval.string = scan_string ();
+
+ /* Check if string is "define_operator"; if so, return
+ a DEFOP token instead. */
+ if (!strcmp (yylval.string, "define_operator"))
+ {
+ free (yylval.string);
+ yylval.string = 0;
+ return DEFOP;
+ }
+ return STRING;
+ }
+ return c & 0xff;
+ }
+ }
+}