+++ /dev/null
-/* Token-reader for Bison's input parser,
- Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002
- Free Software Foundation, Inc.
-
- This file is part of Bison, the GNU Compiler Compiler.
-
- Bison 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.
-
- Bison 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 Bison; see the file COPYING. If not, write to
- the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-#include "system.h"
-#include "getargs.h"
-#include "files.h"
-#include "symtab.h"
-#include "options.h"
-#include "lex.h"
-#include "complain.h"
-#include "gram.h"
-#include "quote.h"
-
-/* Buffer for storing the current token. */
-static struct obstack token_obstack;
-const char *token_buffer = NULL;
-
-symbol_t *symval = NULL;
-int numval;
-
-/* A token to be reread, see unlex and lex. */
-static token_t unlexed = tok_undef;
-static symbol_t *unlexed_symval = NULL;
-static const char *unlexed_token_buffer = NULL;
-
-void
-lex_init (void)
-{
- obstack_init (&token_obstack);
- unlexed = tok_undef;
-}
-
-
-void
-lex_free (void)
-{
- obstack_free (&token_obstack, NULL);
-}
-
-
-int
-skip_white_space (void)
-{
- int c;
- int inside;
-
- c = getc (finput);
-
- for (;;)
- {
- int cplus_comment;
-
- switch (c)
- {
- case '/':
- /* FIXME: Should probably be merged with copy_comment. */
- c = getc (finput);
- if (c != '*' && c != '/')
- {
- complain (_("unexpected `/' found and ignored"));
- break;
- }
- cplus_comment = (c == '/');
-
- c = getc (finput);
-
- inside = 1;
- while (inside)
- {
- if (!cplus_comment && c == '*')
- {
- while (c == '*')
- c = getc (finput);
-
- if (c == '/')
- {
- inside = 0;
- c = getc (finput);
- }
- }
- else if (c == '\n')
- {
- lineno++;
- if (cplus_comment)
- inside = 0;
- c = getc (finput);
- }
- else if (c == EOF)
- fatal (_("unterminated comment"));
- else
- c = getc (finput);
- }
-
- break;
-
- case '\n':
- lineno++;
-
- case ' ':
- case '\t':
- case '\f':
- c = getc (finput);
- break;
-
- default:
- return c;
- }
- }
-}
-
-
-/*-----------------------------------------------------.
-| Do a getc, but give error message if EOF encountered |
-`-----------------------------------------------------*/
-
-int
-xgetc (FILE *f)
-{
- int c = getc (f);
- if (c == EOF)
- fatal (_("unexpected end of file"));
- return c;
-}
-
-
-/*---------------------------------------------------------------.
-| Read one literal character from FINPUT, process \-escapes, and |
-| return the character. |
-`---------------------------------------------------------------*/
-
-char
-literalchar (void)
-{
- int c;
- int res;
-
- c = xgetc (finput);
- if (c == '\n')
- {
- complain (_("unescaped newline in constant"));
- ungetc (c, finput);
- res = '?';
- }
- else if (c != '\\')
- {
- res = c;
- }
- else
- {
- c = xgetc (finput);
- if (c == 't')
- res = '\t';
- else if (c == 'n')
- res = '\n';
- else if (c == 'a')
- res = '\007';
- else if (c == 'r')
- res = '\r';
- else if (c == 'f')
- res = '\f';
- else if (c == 'b')
- res = '\b';
- else if (c == 'v')
- res = '\013';
- else if (c == '\\')
- res = '\\';
- else if (c == '\'')
- res = '\'';
- else if (c == '\"')
- res = '\"';
- else if (c <= '7' && c >= '0')
- {
- res = 0;
- while (c <= '7' && c >= '0')
- {
- res = (res * 8) + (c - '0');
- if (res >= 256 || res < 0)
- {
- complain (_("octal value outside range 0...255: `\\%o'"),
- res);
- res &= 0xFF;
- break;
- }
- c = xgetc (finput);
- }
- ungetc (c, finput);
- }
- else if (c == 'x')
- {
- c = xgetc (finput);
- res = 0;
- while (1)
- {
- if (c >= '0' && c <= '9')
- res *= 16, res += c - '0';
- else if (c >= 'a' && c <= 'f')
- res *= 16, res += c - 'a' + 10;
- else if (c >= 'A' && c <= 'F')
- res *= 16, res += c - 'A' + 10;
- else
- break;
- if (res >= 256 || res < 0)
- {
- complain (_("hexadecimal value above 255: `\\x%x'"), res);
- res &= 0xFF;
- break;
- }
- c = xgetc (finput);
- }
- ungetc (c, finput);
- }
- else
- {
- char badchar [] = "c";
- badchar[0] = c;
- complain (_("unknown escape sequence: `\\' followed by `%s'"),
- quote (badchar));
- res = '?';
- }
- } /* has \ */
-
- return res;
-}
-
-
-void
-unlex (token_t token)
-{
- unlexed = token;
- unlexed_token_buffer = token_buffer;
- unlexed_symval = symval;
-}
-
-/*-----------------------------------------------------------------.
-| We just read `<' from FIN. Store in TOKEN_BUFFER, the type name |
-| specified between the `<...>'. |
-`-----------------------------------------------------------------*/
-
-void
-read_type_name (FILE *fin)
-{
- int c = getc (fin);
-
- while (c != '>')
- {
- if (c == EOF)
- fatal (_("unterminated type name at end of file"));
- if (c == '\n')
- {
- complain (_("unterminated type name"));
- ungetc (c, fin);
- break;
- }
-
- obstack_1grow (&token_obstack, c);
- c = getc (fin);
- }
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
-}
-
-
-token_t
-lex (void)
-{
- int c;
-
- /* Just to make sure. */
- token_buffer = NULL;
-
- if (unlexed != tok_undef)
- {
- token_t res = unlexed;
- symval = unlexed_symval;
- token_buffer = unlexed_token_buffer;
- unlexed = tok_undef;
- return res;
- }
-
- c = skip_white_space ();
-
- switch (c)
- {
- case EOF:
- token_buffer = "EOF";
- return tok_eof;
-
- case 'A': case 'B': case 'C': case 'D': case 'E':
- case 'F': case 'G': case 'H': case 'I': case 'J':
- case 'K': case 'L': case 'M': case 'N': case 'O':
- case 'P': case 'Q': case 'R': case 'S': case 'T':
- case 'U': case 'V': case 'W': case 'X': case 'Y':
- case 'Z':
- case 'a': case 'b': case 'c': case 'd': case 'e':
- case 'f': case 'g': case 'h': case 'i': case 'j':
- case 'k': case 'l': case 'm': case 'n': case 'o':
- case 'p': case 'q': case 'r': case 's': case 't':
- case 'u': case 'v': case 'w': case 'x': case 'y':
- case 'z':
- case '.': case '_':
-
- while (isalnum (c) || c == '_' || c == '.')
- {
- obstack_1grow (&token_obstack, c);
- c = getc (finput);
- }
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
- ungetc (c, finput);
- symval = getsym (token_buffer);
- return tok_identifier;
-
- case '0': case '1': case '2': case '3': case '4':
- case '5': case '6': case '7': case '8': case '9':
- {
- numval = 0;
-
- while (isdigit (c))
- {
- obstack_1grow (&token_obstack, c);
- numval = numval * 10 + c - '0';
- c = getc (finput);
- }
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
- ungetc (c, finput);
- return tok_number;
- }
-
- case '\'':
- /* parse the literal token and compute character code in code */
-
- {
- int code = literalchar ();
-
- obstack_1grow (&token_obstack, '\'');
- obstack_1grow (&token_obstack, code);
-
- c = getc (finput);
- if (c != '\'')
- {
- complain (_("use \"...\" for multi-character literal tokens"));
- while (literalchar () != '\'')
- /* Skip. */;
- }
- obstack_1grow (&token_obstack, '\'');
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
- symval = getsym (token_buffer);
- symbol_class_set (symval, token_sym);
- symbol_user_token_number_set (symval, code);
- return tok_identifier;
- }
-
- case '\"':
- /* parse the literal string token and treat as an identifier */
-
- {
- int code;
-
- obstack_1grow (&token_obstack, '\"');
- /* Read up to and including ". */
- do
- {
- code = literalchar ();
- obstack_1grow (&token_obstack, code);
- }
- while (code != '\"');
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
-
- symval = getsym (token_buffer);
- symbol_class_set (symval, token_sym);
- return tok_identifier;
- }
-
- case ',':
- token_buffer = ",";
- return tok_comma;
-
- case ':':
- token_buffer = ":";
- return tok_colon;
-
- case ';':
- token_buffer = ";";
- return tok_semicolon;
-
- case '|':
- token_buffer = "|";
- return tok_bar;
-
- case '{':
- token_buffer = "{";
- return tok_left_curly;
-
- case '=':
- obstack_1grow (&token_obstack, c);
- do
- {
- c = getc (finput);
- obstack_1grow (&token_obstack, c);
- if (c == '\n')
- lineno++;
- }
- while (c == ' ' || c == '\n' || c == '\t');
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
-
- if (c == '{')
- {
- return tok_left_curly;
- }
- else
- {
- ungetc (c, finput);
- return tok_illegal;
- }
-
- case '<':
- read_type_name (finput);
- return tok_typename;
-
- case '%':
- return parse_percent_token ();
-
- default:
- obstack_1grow (&token_obstack, c);
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
- return tok_illegal;
- }
-}
-
-/* This function is a strcmp, which doesn't differentiate `-' and `_'
- chars. */
-
-static int
-option_strcmp (const char *left, const char *right)
-{
- const unsigned char *l, *r;
- int c;
-
- assert (left);
- assert (right);
- l = (const unsigned char *)left;
- r = (const unsigned char *)right;
- while (((c = *l - *r++) == 0 && *l != '\0')
- || ((*l == '-' || *l == '_') && (*r == '_' || *r == '-')))
- l++;
- return c;
-}
-
-/* Parse a token which starts with %.
- Assumes the % has already been read and discarded. */
-
-token_t
-parse_percent_token (void)
-{
- const struct option_table_s *tx = NULL;
- const char *arg = NULL;
- /* Where the ARG was found in token_buffer. */
- size_t arg_offset = 0;
-
- int c = getc (finput);
- obstack_1grow (&token_obstack, '%');
- obstack_1grow (&token_obstack, c);
-
- if (!isalpha (c))
- {
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
-
- switch (c)
- {
- case '%':
- return tok_two_percents;
-
- case '{':
- return tok_percent_left_curly;
-
- /* The following guys are here for backward compatibility with
- very ancient Yacc versions. The paper of Johnson mentions
- them (as ancient :). */
- case '<':
- return tok_left;
-
- case '>':
- return tok_right;
-
- case '2':
- return tok_nonassoc;
-
- case '0':
- return tok_token;
-
- case '=':
- return tok_prec;
-
- default:
- return tok_illegal;
- }
- }
-
- while (c = getc (finput), isalpha (c) || c == '_' || c == '-')
- {
- if (c == '_')
- c = '-';
- obstack_1grow (&token_obstack, c);
- }
-
- /* %DIRECTIVE="ARG". Separate into
- TOKEN_BUFFER = `%DIRECTIVE\0ARG\0'.
- This is a bit hackish, but once we move to a Bison parser,
- things will be cleaned up. */
- if (c == '=')
- {
- /* End of the directive. We skip the `='. */
- obstack_1grow (&token_obstack, '\0');
- /* Fetch the ARG if present. */
- c = getc (finput);
- if (c == '"')
- {
- int code;
- arg_offset = obstack_object_size (&token_obstack);
- /* Read up to and including `"'. Do not append the closing
- `"' in the output: it's not part of the ARG. */
- while ((code = literalchar ()) != '"')
- obstack_1grow (&token_obstack, code);
- }
- /* else: should be an error. */
- }
- else
- ungetc (c, finput);
-
- obstack_1grow (&token_obstack, '\0');
- token_buffer = obstack_finish (&token_obstack);
- if (arg_offset)
- arg = token_buffer + arg_offset;
-
- /* table lookup % directive */
- for (tx = option_table; tx->name; tx++)
- if ((tx->access == opt_percent || tx->access == opt_both)
- && option_strcmp (token_buffer + 1, tx->name) == 0)
- break;
-
- if (arg && tx->ret_val != tok_stropt)
- fatal (_("`%s' supports no argument: %s"), token_buffer, quote (arg));
-
-
- switch (tx->ret_val)
- {
- case tok_stropt:
- assert (tx->flag);
- if (arg)
- {
- char **flag = (char **) tx->flag;
- /* Keep only the first assignment: command line options have
- already been processed, and we want them to have
- precedence. Side effect: if this %-option is used
- several times, only the first is honored. Bah. */
- if (!*flag)
- *flag = xstrdup (arg);
- }
- else
- fatal (_("`%s' requires an argument"), token_buffer);
- return tok_noop;
- break;
-
- case tok_intopt:
- assert (tx->flag);
- *((int *) (tx->flag)) = 1;
- return tok_noop;
- break;
-
- case tok_obsolete:
- fatal (_("`%s' is no longer supported"), token_buffer);
- return tok_noop;
- break;
-
- default:
- return tx->ret_val;
- break;
- }
- abort ();
-}
projects / bison.git / blobdiff