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/* 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 "hconfig.h"
#include "bi-parser.h"
/* 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 = (char *) malloc (nbytes);
if (!tmp)
{
fprintf (stderr, "can't allocate %d bytes (out of virtual memory)\n", nbytes);
exit (FATAL_EXIT_CODE);
}
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 = (block
? (char *) realloc (block, nbytes)
: (char *) malloc (nbytes));
if (!tmp)
{
fprintf (stderr, "can't reallocate %d bytes (out of virtual memory)\n", nbytes);
exit (FATAL_EXIT_CODE);
}
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;
}
}
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.