diff options
Diffstat (limited to 'contrib/gcc/bi-lexer.c')
| -rw-r--r-- | contrib/gcc/bi-lexer.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/contrib/gcc/bi-lexer.c b/contrib/gcc/bi-lexer.c new file mode 100644 index 0000000..6601c52 --- /dev/null +++ b/contrib/gcc/bi-lexer.c @@ -0,0 +1,167 @@ +/* Lexer for scanner of bytecode definition file. + Copyright (C) 1993, 1995 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, 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +#include <stdio.h> +#include "hconfig.h" +#include "bi-parser.h" + + +/* Safely allocate NBYTES bytes of memory. Returns 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; + } + } +} |
