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authorMatthias Schiffer <mschiffer@universe-factory.net>2013-08-14 01:19:33 +0200
committerMatthias Schiffer <mschiffer@universe-factory.net>2013-08-14 01:19:33 +0200
commitbf721f718ed2ca3e5d409a2f6b48312ee95d2e4e (patch)
tree3058045f16e69b423a91bffc1a7ed79ea77489fa /src/lex.c
parentcd0f973cf622f7476514143122f699f5a9277c44 (diff)
downloadfastd-bf721f718ed2ca3e5d409a2f6b48312ee95d2e4e.tar
fastd-bf721f718ed2ca3e5d409a2f6b48312ee95d2e4e.zip
Implement new lexer that is not generated by flex to reduce code size
Diffstat (limited to 'src/lex.c')
-rw-r--r--src/lex.c457
1 files changed, 457 insertions, 0 deletions
diff --git a/src/lex.c b/src/lex.c
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+++ b/src/lex.c
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+/*
+ Copyright (c) 2012-2013, Matthias Schiffer <mschiffer@universe-factory.net>
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "lex.h"
+
+#include <stdlib.h>
+
+
+struct fastd_lex {
+ FILE *file;
+
+ bool needspace;
+
+ size_t start;
+ size_t end;
+ size_t tok_len;
+ char buffer[1024];
+};
+
+
+typedef struct keyword {
+ const char *keyword;
+ int token;
+} keyword_t;
+
+/* the keyword list must be sorted */
+static const keyword_t keywords[] = {
+ { "addresses", TOK_ADDRESSES },
+ { "any", TOK_ANY },
+ { "as", TOK_AS },
+ { "auto", TOK_AUTO },
+ { "bind", TOK_BIND },
+ { "capabilities", TOK_CAPABILITIES },
+ { "crypto", TOK_CRYPTO },
+ { "debug", TOK_DEBUG },
+ { "default", TOK_DEFAULT },
+ { "disestablish", TOK_DISESTABLISH },
+ { "down", TOK_DOWN },
+ { "drop", TOK_DROP },
+ { "early", TOK_EARLY },
+ { "error", TOK_ERROR },
+ { "establish", TOK_ESTABLISH },
+ { "fatal", TOK_FATAL },
+ { "float", TOK_FLOAT },
+ { "forward", TOK_FORWARD },
+ { "from", TOK_FROM },
+ { "group", TOK_GROUP },
+ { "hide", TOK_HIDE },
+ { "include", TOK_INCLUDE },
+ { "info", TOK_INFO },
+ { "interface", TOK_INTERFACE },
+ { "ip", TOK_IP },
+ { "ipv4", TOK_IPV4 },
+ { "ipv6", TOK_IPV6 },
+ { "key", TOK_KEY },
+ { "level", TOK_LEVEL },
+ { "limit", TOK_LIMIT },
+ { "log", TOK_LOG },
+ { "mac", TOK_MAC },
+ { "method", TOK_METHOD },
+ { "mode", TOK_MODE },
+ { "mtu", TOK_MTU },
+ { "no", TOK_NO },
+ { "on", TOK_ON },
+ { "peer", TOK_PEER },
+ { "peers", TOK_PEERS },
+ { "pmtu", TOK_PMTU },
+ { "port", TOK_PORT },
+ { "post-down", TOK_POST_DOWN },
+ { "pre-up", TOK_PRE_UP },
+ { "protocol", TOK_PROTOCOL },
+ { "remote", TOK_REMOTE },
+ { "secret", TOK_SECRET },
+ { "stderr", TOK_STDERR },
+ { "syslog", TOK_SYSLOG },
+ { "tap", TOK_TAP },
+ { "to", TOK_TO },
+ { "tun", TOK_TUN },
+ { "up", TOK_UP },
+ { "use", TOK_USE },
+ { "user", TOK_USER },
+ { "verbose", TOK_VERBOSE },
+ { "verify", TOK_VERIFY },
+ { "warn", TOK_WARN },
+ { "yes", TOK_YES },
+};
+
+static int compare_keywords(const void *v1, const void *v2) {
+ const keyword_t *k1 = v1, *k2 = v2;
+ return strcmp(k1->keyword, k2->keyword);
+}
+
+
+static bool advance(fastd_lex_t *lex) {
+ if (lex->start > 0) {
+ memmove(lex->buffer, lex->buffer+lex->start, lex->end - lex->start);
+ lex->end -= lex->start;
+ lex->start = 0;
+ }
+
+ if (lex->end == sizeof(lex->buffer))
+ return false;
+
+ size_t l = fread(lex->buffer+lex->end, 1, sizeof(lex->buffer) - lex->end, lex->file);
+
+ lex->end += l;
+ return l;
+}
+
+static inline char current(fastd_lex_t *lex) {
+ return lex->buffer[lex->start + lex->tok_len];
+}
+
+static char* get_token(fastd_lex_t *lex) {
+ return strndup(lex->buffer+lex->start, lex->tok_len);
+}
+
+static bool next(YYLTYPE *yylloc, fastd_lex_t *lex, bool move) {
+ if (lex->start + lex->tok_len >= lex->end)
+ return false;
+
+ if (current(lex) == '\n') {
+ yylloc->last_column = 0;
+ yylloc->last_line++;
+ }
+ else {
+ yylloc->last_column++;
+ }
+
+ if (move)
+ lex->start++;
+ else
+ lex->tok_len++;
+
+
+ if (lex->start + lex->tok_len >= lex->end)
+ return advance(lex);
+
+ return true;
+}
+
+static void consume(fastd_lex_t *lex, bool needspace) {
+ lex->start += lex->tok_len;
+ lex->tok_len = 0;
+
+ lex->needspace = needspace;
+}
+
+static int syntax_error(YYSTYPE *yylval, fastd_lex_t *lex) {
+ yylval->error = "syntax error";
+ return -1;
+}
+
+static int io_error(YYSTYPE *yylval, fastd_lex_t *lex) {
+ yylval->error = "I/O error";
+ return -1;
+}
+
+static inline int end(YYSTYPE *yylval, fastd_lex_t *lex) {
+ if (ferror(lex->file))
+ return io_error(yylval, lex);
+
+ return 0;
+}
+
+static int consume_comment(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ char prev = 0;
+
+ while (next(yylloc, lex, true)) {
+ if (prev == '*' && current(lex) == '/') {
+ next(yylloc, lex, true);
+ consume(lex, false);
+ return 0;
+ }
+
+ prev = current(lex);
+ }
+
+ if (ferror(lex->file))
+ return io_error(yylval, lex);
+
+ yylval->error = "unterminated block comment";
+ return -1;
+}
+
+static int unterminated_string(YYSTYPE *yylval, fastd_lex_t *lex) {
+ if (ferror(lex->file))
+ return io_error(yylval, lex);
+
+ yylval->error = "unterminated string";
+ return -1;
+}
+
+static int parse_string(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ char *buf = NULL;
+ size_t len = 1024;
+ size_t pos = 0;
+
+ if (lex->needspace)
+ return syntax_error(yylval, lex);
+
+ buf = malloc(len);
+
+ while (true) {
+ if (!next(yylloc, lex, true)) {
+ free(buf);
+ return unterminated_string(yylval, lex);
+ }
+
+ char cur = current(lex);
+
+ if (cur == '"')
+ break;
+
+ if (cur == '\\') {
+ if (!next(yylloc, lex, true)) {
+ free(buf);
+ return unterminated_string(yylval, lex);
+ }
+
+ cur = current(lex);
+
+ if (cur == '\n')
+ continue;
+ }
+
+ if (pos >= len) {
+ len *= 2;
+ buf = realloc(buf, len);
+ }
+
+ buf[pos++] = cur;
+ }
+
+ yylval->str = fastd_string_stack_dupn(buf, pos);
+ free(buf);
+
+ next(yylloc, lex, true);
+ consume(lex, true);
+
+ return TOK_STRING;
+}
+
+static int parse_ipv6_address(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ if (lex->needspace)
+ return syntax_error(yylval, lex);
+
+ while (next(yylloc, lex, false)) {
+ char cur = current(lex);
+
+ if (!((cur >= '0' && cur <= '9') || cur == ':'))
+ break;
+ }
+
+ bool ok = (current(lex) == ']');
+
+ if (ok) {
+ lex->buffer[lex->start + lex->tok_len] = 0;
+ ok = inet_pton(AF_INET6, lex->buffer+lex->start+1, &yylval->addr6);
+ }
+
+ if (!ok) {
+ yylval->error = "invalid address";
+ return -1;
+ }
+
+ next(yylloc, lex, true);
+ consume(lex, true);
+
+ return TOK_ADDR6;
+}
+
+static int parse_ipv4_address(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ if (lex->needspace)
+ return syntax_error(yylval, lex);
+
+ while (next(yylloc, lex, false)) {
+ char cur = current(lex);
+
+ if (!((cur >= '0' && cur <= '9') || cur == '.'))
+ break;
+ }
+
+ char *token = get_token(lex);
+ bool ok = inet_pton(AF_INET, token, &yylval->addr4);
+
+ free(token);
+
+ if (!ok) {
+ yylval->error = "invalid address";
+ return -1;
+ }
+
+ return TOK_ADDR4;
+}
+
+static int parse_number(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ if (lex->needspace)
+ return syntax_error(yylval, lex);
+
+ while (next(yylloc, lex, false)) {
+ char cur = current(lex);
+
+ if (cur == '.')
+ return parse_ipv4_address(yylval, yylloc, lex);
+
+ if (!(cur >= '0' && cur <= '9'))
+ break;
+ }
+
+ char *endptr, *token = get_token(lex);
+ yylval->uint64 = strtoull(token, &endptr, 10);
+
+ bool ok = !*endptr;
+ free(token);
+
+ if (!ok) {
+ yylval->error = "invalid integer constant";
+ return -1;
+ }
+
+ return TOK_UINT;
+}
+
+static int parse_keyword(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ if (lex->needspace)
+ return syntax_error(yylval, lex);
+
+ while (next(yylloc, lex, false)) {
+ char cur = current(lex);
+
+ if (!((cur >= 'a' && cur <= 'z') || (cur >= '0' && cur <= '9') || cur == '-'))
+ break;
+ }
+
+ char *token = get_token(lex);
+ const keyword_t key = {token};
+ const keyword_t *ret = bsearch(&key, keywords, sizeof(keywords)/sizeof(keyword_t), sizeof(keyword_t), compare_keywords);
+ free(token);
+
+ if (!ret)
+ return syntax_error(yylval, lex);
+
+ consume(lex, true);
+
+ return ret->token;
+}
+
+fastd_lex_t* fastd_lex_init(FILE *file) {
+ fastd_lex_t *lex = calloc(1, sizeof(fastd_lex_t));
+ lex->file = file;
+
+ advance(lex);
+
+ return lex;
+}
+
+void fastd_lex_destroy(fastd_lex_t *lex) {
+ if (!lex)
+ return;
+
+ free(lex);
+}
+
+int fastd_lex(YYSTYPE *yylval, YYLTYPE *yylloc, fastd_lex_t *lex) {
+ int token;
+
+ while (lex->end > lex->start) {
+ yylloc->first_line = yylloc->last_line;
+ yylloc->first_column = yylloc->last_column+1;
+
+ switch (current(lex)) {
+ case ' ':
+ case '\n':
+ case '\t':
+ case '\r':
+ next(yylloc, lex, true);
+ consume(lex, false);
+ continue;
+
+ case ';':
+ case ':':
+ case '{':
+ case '}':
+ token = current(lex);
+ next(yylloc, lex, true);
+ consume(lex, false);
+ return token;
+
+ case '/':
+ if (!next(yylloc, lex, true))
+ return syntax_error(yylval, lex);
+
+ if (current(lex) == '*') {
+ token = consume_comment(yylval, yylloc, lex);
+ if (token)
+ return token;
+
+ continue;
+ }
+
+ if (current(lex) != '/')
+ return syntax_error(yylval, lex);
+
+ /* fall-through */
+ case '#':
+ while (next(yylloc, lex, true)) {
+ if (current(lex) == '\n')
+ break;
+ }
+
+ next(yylloc, lex, true);
+ consume(lex, false);
+ continue;
+
+ case '"':
+ return parse_string(yylval, yylloc, lex);
+
+ case '[':
+ return parse_ipv6_address(yylval, yylloc, lex);
+
+ case '0' ... '9':
+ return parse_number(yylval, yylloc, lex);
+
+ case 'a' ... 'z':
+ return parse_keyword(yylval, yylloc, lex);
+
+ default:
+ return syntax_error(yylval, lex);
+ }
+ }
+
+ return end(yylval, lex);
+}