diff options
Diffstat (limited to 'src/libstrongswan/settings/settings_lexer.l')
| -rw-r--r-- | src/libstrongswan/settings/settings_lexer.l | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/src/libstrongswan/settings/settings_lexer.l b/src/libstrongswan/settings/settings_lexer.l new file mode 100644 index 000000000..c6546f464 --- /dev/null +++ b/src/libstrongswan/settings/settings_lexer.l @@ -0,0 +1,201 @@ +%{ +/* + * Copyright (C) 2014 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program 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 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program 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. + */ + +#include <utils/parser_helper.h> + +#include "settings_parser.h" + +bool settings_parser_open_next_file(parser_helper_t *ctx); + +static void include_files(parser_helper_t *ctx); + +%} +%option debug +%option warn + +/* use start conditions stack */ +%option stack + +/* do not declare unneded functions */ +%option noinput noyywrap + +/* don't use global variables, and interact properly with bison */ +%option reentrant bison-bridge + +/* maintain the line number */ +%option yylineno + +/* don't generate a default rule */ +%option nodefault + +/* prefix function/variable declarations */ +%option prefix="settings_parser_" +/* don't change the name of the output file otherwise autotools has issues */ +%option outfile="lex.yy.c" + +/* type of our extra data */ +%option extra-type="parser_helper_t*" + +/* state used to scan include file patterns */ +%x inc +/* state used to scan quoted strings */ +%x str + +%% + +[\t ]*#[^\n]* /* eat comments */ +[\t ]+ /* eat whitespace */ +\n|#.*\n return NEWLINE; /* also eats comments at the end of a line */ + +"{" | +"}" | +"=" return yytext[0]; + +"include"[\t ]+/[^=] { + yyextra->string_init(yyextra); + yy_push_state(inc, yyscanner); +} + +"\"" { + yyextra->string_init(yyextra); + yy_push_state(str, yyscanner); +} + +[^#{}="\n\t ]+ { + yylval->s = strdup(yytext); + return NAME; +} + +<inc>{ + /* we allow all characters except #, } and spaces, they can be escaped */ + <<EOF>> | + [#}\n\t ] { + if (*yytext) + { + switch (yytext[0]) + { + case '\n': + /* put the newline back to fix the line numbers */ + unput('\n'); + yy_set_bol(0); + break; + case '#': + case '}': + /* these are parsed outside of this start condition */ + unput(yytext[0]); + break; + } + } + include_files(yyextra); + yy_pop_state(yyscanner); + } + "\"" { /* string include */ + yy_push_state(str, yyscanner); + } + \\ { + yyextra->string_add(yyextra, yytext); + } + \\["#} ] { + yyextra->string_add(yyextra, yytext+1); + } + [^"\\#}\n\t ]+ { + yyextra->string_add(yyextra, yytext); + } +} + +<str>{ + "\"" | + <<EOF>> | + \n | + \\ { + if (!streq(yytext, "\"")) + { + if (streq(yytext, "\n")) + { /* put the newline back to fix the line numbers */ + unput('\n'); + yy_set_bol(0); + } + PARSER_DBG1(yyextra, "unterminated string detected"); + } + if (yy_top_state(yyscanner) == inc) + { /* string include */ + include_files(yyextra); + yy_pop_state(yyscanner); + yy_pop_state(yyscanner); + } + else + { + yy_pop_state(yyscanner); + yylval->s = yyextra->string_get(yyextra); + return STRING; + } + } + \\n yyextra->string_add(yyextra, "\n"); + \\r yyextra->string_add(yyextra, "\r"); + \\t yyextra->string_add(yyextra, "\t"); + \\b yyextra->string_add(yyextra, "\b"); + \\f yyextra->string_add(yyextra, "\f"); + \\(.|\n) { + yyextra->string_add(yyextra, yytext+1); + } + [^\\\n"]+ { + yyextra->string_add(yyextra, yytext); + } +} + +<<EOF>> { + settings_parser_pop_buffer_state(yyscanner); + if (!settings_parser_open_next_file(yyextra) && !YY_CURRENT_BUFFER) + { + yyterminate(); + } +} + +%% + +/** + * Open the next file, if any is queued and readable, otherwise returns FALSE. + */ +bool settings_parser_open_next_file(parser_helper_t *ctx) +{ + FILE *file; + + file = ctx->file_next(ctx); + if (!file) + { + return FALSE; + } + + settings_parser_set_in(file, ctx->scanner); + settings_parser_push_buffer_state( + settings_parser__create_buffer(file, YY_BUF_SIZE, + ctx->scanner), ctx->scanner); + return TRUE; +} + +/** + * Assumes that the file pattern to include is currently stored as string on + * the helper object. + */ +static void include_files(parser_helper_t *ctx) +{ + char *pattern = ctx->string_get(ctx); + + ctx->file_include(ctx, pattern); + free(pattern); + + settings_parser_open_next_file(ctx); +} |