more work on local variable support
[cparser] / lexer.c
diff --git a/lexer.c b/lexer.c
index 857ff85..1300b3d 100644 (file)
--- a/lexer.c
+++ b/lexer.c
@@ -1,9 +1,11 @@
 #include <config.h>
 
-#include "lexer_t.h"
+#include "lexer.h"
 #include "token_t.h"
 #include "symbol_table_t.h"
 #include "adt/error.h"
+#include "adt/strset.h"
+#include "adt/util.h"
 
 #include <assert.h>
 #include <errno.h>
 //#define DEBUG_CHARS
 #define MAX_PUTBACK 3
 
-static int               c;
-source_position_t source_position;
-static FILE             *input;
-static char              buf[1027];
-static const char       *bufend;
-static const char       *bufpos;
-static strset_t          stringset;
-//static FILE            **input_stack;
-//static char            **buf_stack;
+static int         c;
+token_t            lexer_token;
+symbol_t          *symbol_L;
+static FILE       *input;
+static char        buf[1024 + MAX_PUTBACK];
+static const char *bufend;
+static const char *bufpos;
+static strset_t    stringset;
 
-static
-void error_prefix_at(const char *input_name, unsigned linenr)
+static void error_prefix_at(const char *input_name, unsigned linenr)
 {
-       fprintf(stderr, "%s:%d: Error: ", input_name, linenr);
+       fprintf(stderr, "%s:%u: Error: ", input_name, linenr);
 }
 
-static
-void error_prefix()
+static void error_prefix(void)
 {
-       error_prefix_at(source_position.input_name, source_position.linenr);
+       error_prefix_at(lexer_token.source_position.input_name,
+                       lexer_token.source_position.linenr);
 }
 
-static
-void parse_error(const char *msg)
+static void parse_error(const char *msg)
 {
        error_prefix();
        fprintf(stderr, "%s\n", msg);
 }
 
-static inline
-void next_char()
+static inline void next_real_char(void)
 {
        bufpos++;
        if(bufpos >= bufend) {
@@ -57,82 +55,106 @@ void next_char()
                bufend = buf + MAX_PUTBACK + s;
        }
        c = *(bufpos);
-#ifdef DEBUG_CHARS
-       printf("nchar '%c'\n", c);
-#endif
 }
 
-static inline
-void put_back(int pc)
+static inline void put_back(int pc)
 {
-       char *p = (char*) bufpos - 1;
-       bufpos--;
-       assert(p >= buf);
+       assert(bufpos >= buf);
+       assert(bufpos < buf+MAX_PUTBACK || *bufpos == pc);
+
+       char *p = buf + (bufpos - buf);
        *p = pc;
 
+       /* going backwards in the buffer is legal as long as it's not more often
+        * than MAX_PUTBACK */
+       bufpos--;
+
 #ifdef DEBUG_CHARS
        printf("putback '%c'\n", pc);
 #endif
 }
 
+static inline void next_char(void);
+
+#define MATCH_NEWLINE(code)                   \
+       case '\r':                                \
+               next_char();                          \
+               if(c == '\n') {                       \
+                       next_char();                      \
+               }                                     \
+               lexer_token.source_position.linenr++; \
+               code;                                 \
+       case '\n':                                \
+               next_char();                          \
+               lexer_token.source_position.linenr++; \
+               code;
 
-static
-int replace_trigraph(void)
+#define eat(c_type)  do { assert(c == c_type); next_char(); } while(0)
+
+static void maybe_concat_lines(void)
 {
-#define MATCH_TRIGRAPH(ch,replacement)           \
-       case ch:                                     \
-               c = replacement;                         \
-               return 1;
+       eat('\\');
 
        switch(c) {
-       MATCH_TRIGRAPH('=', '#')
-       MATCH_TRIGRAPH('(', '[')
-       MATCH_TRIGRAPH('/', '\\')
-       MATCH_TRIGRAPH(')', ']')
-       MATCH_TRIGRAPH('\'', '^')
-       MATCH_TRIGRAPH('<', '{')
-       MATCH_TRIGRAPH('!', '|')
-       MATCH_TRIGRAPH('>', '}')
-       MATCH_TRIGRAPH('-', '~')
+       MATCH_NEWLINE(return;)
+
        default:
                break;
        }
 
-       return 0;
-}
-
-#define SKIP_TRIGRAPHS(custom_putback, no_trigraph_code) \
-       case '?':                                  \
-               next_char();                           \
-               if(c != '?') {                         \
-                       custom_putback;                    \
-                       put_back(c);                       \
-                       c = '?';                           \
-                       no_trigraph_code;                  \
-               }                                      \
-               next_char();                           \
-               if(replace_trigraph()) {               \
-                       break;                             \
-               }                                      \
-               custom_putback;                        \
-               put_back('?');                         \
-               put_back(c);                           \
-               c = '?';                               \
-               no_trigraph_code;
-
-#define EAT_NEWLINE(newline_code)              \
-       if(c == '\r') {                            \
-               next_char();                           \
-               if(c == '\n')                          \
-                       next_char();                       \
-               source_position.linenr++;              \
-               newline_code;                          \
-       } else if(c == '\n') {                     \
-               next_char();                           \
-               source_position.linenr++;              \
-               newline_code;                          \
+       put_back(c);
+       c = '\\';
+}
+
+static inline void next_char(void)
+{
+       next_real_char();
+
+#if 0
+       /* filter trigraphs */
+       if(UNLIKELY(c == '\\')) {
+               maybe_concat_lines();
+               goto end_of_next_char;
+       }
+
+       if(LIKELY(c != '?'))
+               goto end_of_next_char;
+
+       next_real_char();
+       if(LIKELY(c != '?')) {
+               put_back(c);
+               c = '?';
+               goto end_of_next_char;
+       }
+
+       next_real_char();
+       switch(c) {
+       case '=': c = '#'; break;
+       case '(': c = '['; break;
+       case '/': c = '\\'; maybe_concat_lines(); break;
+       case ')': c = ']'; break;
+       case '\'': c = '^'; break;
+       case '<': c = '{'; break;
+       case '!': c = '|'; break;
+       case '>': c = '}'; break;
+       case '-': c = '~'; break;
+       default:
+               put_back('?');
+               put_back(c);
+               c = '?';
+               break;
        }
 
+end_of_next_char:
+#endif
+       (void) maybe_concat_lines;
+#ifdef DEBUG_CHARS
+       printf("nchar '%c'\n", c);
+#else
+       ;
+#endif
+}
+
 #define SYMBOL_CHARS  \
        case 'a':         \
        case 'b':         \
@@ -200,8 +222,7 @@ int replace_trigraph(void)
        case '8':         \
        case '9':
 
-static
-void parse_symbol(token_t *token)
+static void parse_symbol(void)
 {
        symbol_t *symbol;
        char     *string;
@@ -211,52 +232,71 @@ void parse_symbol(token_t *token)
 
        while(1) {
                switch(c) {
-               case '\\':
-                       next_char();
-                       EAT_NEWLINE(break;)
-                       goto end_symbol;
-
                DIGITS
                SYMBOL_CHARS
                        obstack_1grow(&symbol_obstack, c);
                        next_char();
                        break;
 
-               case '?':
-                       next_char();
-                       if(c != '?') {
-                               put_back(c);
-                               c = '?';
-                               goto end_symbol;
-                       }
-                       next_char();
-                       if(replace_trigraph())
-                               break;
-                       put_back('?');
-                       put_back(c);
-                       c = '?';
-                       goto end_symbol;
-
                default:
                        goto end_symbol;
                }
        }
+
 end_symbol:
        obstack_1grow(&symbol_obstack, '\0');
 
        string = obstack_finish(&symbol_obstack);
        symbol = symbol_table_insert(string);
 
-       token->type     = symbol->ID;
-       token->v.symbol = symbol;
+       lexer_token.type     = symbol->ID;
+       lexer_token.v.symbol = symbol;
 
        if(symbol->string != string) {
                obstack_free(&symbol_obstack, string);
        }
 }
 
-static
-void parse_number_hex(token_t *token)
+static void parse_integer_suffix(void)
+{
+       if(c == 'U' || c == 'U') {
+               /* TODO do something with the suffixes... */
+               next_char();
+               if(c == 'L' || c == 'l') {
+                       next_char();
+                       if(c == 'L' || c == 'l') {
+                               next_char();
+                       }
+               }
+       } else if(c == 'l' || c == 'L') {
+               next_char();
+               if(c == 'l' || c == 'L') {
+                       next_char();
+                       if(c == 'u' || c == 'U') {
+                               next_char();
+                       }
+               } else if(c == 'u' || c == 'U') {
+                       next_char();
+               }
+       }
+}
+
+static void parse_floating_suffix(void)
+{
+       switch(c) {
+       /* TODO: do something usefull with the suffixes... */
+       case 'f':
+       case 'F':
+       case 'l':
+       case 'L':
+               next_char();
+               break;
+       default:
+               break;
+       }
+}
+
+static void parse_number_hex(void)
 {
        assert(c == 'x' || c == 'X');
        next_char();
@@ -265,12 +305,12 @@ void parse_number_hex(token_t *token)
                !('A' <= c && c <= 'F') &&
                !('a' <= c && c <= 'f')) {
                parse_error("premature end of hex number literal");
-               token->type = T_ERROR;
+               lexer_token.type = T_ERROR;
                return;
        }
 
        int value = 0;
-       for(;;) {
+       while(1) {
                if (isdigit(c)) {
                        value = 16 * value + c - '0';
                } else if ('A' <= c && c <= 'F') {
@@ -278,160 +318,274 @@ void parse_number_hex(token_t *token)
                } else if ('a' <= c && c <= 'f') {
                        value = 16 * value + c - 'a' + 10;
                } else {
-                       token->type     = T_INTEGER;
-                       token->v.intvalue = value;
+                       parse_integer_suffix();
+
+                       lexer_token.type       = T_INTEGER;
+                       lexer_token.v.intvalue = value;
                        return;
                }
                next_char();
        }
+
+       if(c == '.' || c == 'p' || c == 'P') {
+               next_char();
+               panic("Hex floating point numbers not implemented yet");
+       }
 }
 
-static
-void parse_number_oct(token_t *token)
+static void parse_number_oct(void)
 {
-       assert(c == 'o' || c == 'O');
-       next_char();
-
        int value = 0;
-       for(;;) {
-               if ('0' <= c && c <= '7') {
-                       value = 8 * value + c - '0';
-               } else {
-                       token->type     = T_INTEGER;
-                       token->v.intvalue = value;
-                       return;
-               }
+       while(c >= '0' && c <= '7') {
+               value = 8 * value + c - '0';
                next_char();
        }
+       if (c == '8' || c == '9') {
+               parse_error("invalid octal number");
+               lexer_token.type = T_ERROR;
+               return;
+       }
+
+       lexer_token.type       = T_INTEGER;
+       lexer_token.v.intvalue = value;
+
+       parse_integer_suffix();
 }
 
-static
-void parse_number_dec(token_t *token, int first_char)
+static void parse_floatingpoint_exponent(long double value)
 {
-       int value = 0;
-       if(first_char > 0) {
-               assert(first_char >= '0' && first_char <= '9');
-               value = first_char - '0';
+       unsigned int expo = 0;
+       long double  factor = 10.;
+
+       if(c == '-') {
+               next_char();
+               factor = 0.1;
+       } else if(c == '+') {
+               next_char();
        }
 
-       for(;;) {
-               if (isdigit(c)) {
-                       value = 10 * value + c - '0';
-               } else {
-                       token->type     = T_INTEGER;
-                       token->v.intvalue = value;
-                       return;
-               }
+       while(c >= '0' && c <= '9') {
+               expo = 10 * expo + (c - '0');
                next_char();
        }
+
+       while(1) {
+               if(expo & 1)
+                       value *= factor;
+               expo >>= 1;
+               if(expo == 0)
+                       break;
+               factor *= factor;
+       }
+
+       lexer_token.type         = T_FLOATINGPOINT;
+       lexer_token.v.floatvalue = value;
+
+       parse_floating_suffix();
 }
 
-static
-void parse_number(token_t *token)
+static void parse_floatingpoint_fract(int integer_part)
 {
-       // TODO check for overflow
-       // TODO check for various invalid inputs sequences
+       long double value  = integer_part;
+       long double factor = 1.;
+
+       while(c >= '0' && c <= '9') {
+               factor *= 0.1;
+               value  += (c - '0') * factor;
+               next_char();
+       }
+
+       if(c == 'e' || c == 'E') {
+               next_char();
+               parse_floatingpoint_exponent(value);
+               return;
+       }
+
+       lexer_token.type         = T_FLOATINGPOINT;
+       lexer_token.v.floatvalue = value;
+
+       parse_floating_suffix();
+}
+
+static void parse_number_dec(void)
+{
+       int value = 0;
+
+       while(isdigit(c)) {
+               value = 10 * value + c - '0';
+               next_char();
+       }
+
+       if(c == '.') {
+               next_char();
+               parse_floatingpoint_fract(value);
+               return;
+       }
+       if(c == 'e' || c == 'E') {
+               next_char();
+               parse_floatingpoint_exponent(value);
+               return;
+       }
+       parse_integer_suffix();
+
+       lexer_token.type       = T_INTEGER;
+       lexer_token.v.intvalue = value;
+}
 
+static void parse_number(void)
+{
        if (c == '0') {
                next_char();
                switch (c) {
                        case 'X':
-                       case 'x': parse_number_hex(token); break;
-                       case 'o':
-                       case 'O': parse_number_oct(token); break;
-                       default:  parse_number_dec(token, '0');
+                       case 'x':
+                               parse_number_hex();
+                               break;
+                       case '0':
+                       case '1':
+                       case '2':
+                       case '3':
+                       case '4':
+                       case '5':
+                       case '6':
+                       case '7':
+                               parse_number_oct();
+                               break;
+                       case '.':
+                               next_char();
+                               parse_floatingpoint_fract(0);
+                               break;
+                       case 'e':
+                       case 'E':
+                               parse_floatingpoint_exponent(0);
+                               break;
+                       case '8':
+                       case '9':
+                               next_char();
+                               parse_error("invalid octal number");
+                               lexer_token.type = T_ERROR;
+                               return;
+                       default:
+                               put_back(c);
+                               c = '0';
+                               parse_number_dec();
+                               return;
                }
        } else {
-               parse_number_dec(token, 0);
+               parse_number_dec();
        }
 }
 
-static
-int parse_escape_sequence()
+static int parse_octal_sequence(void)
 {
+       int value = 0;
        while(1) {
-               int ec = c;
+               if(c < '0' || c > '7')
+                       break;
+               value = 8 * value + c - '0';
                next_char();
+       }
 
-               switch(ec) {
-               case '"': return '"';
-               case '\'': return'\'';
-               case '\\':
-                       EAT_NEWLINE(break;)
-                       return '\\';
-               case 'a': return '\a';
-               case 'b': return '\b';
-               case 'f': return '\f';
-               case 'n': return '\n';
-               case 'r': return '\r';
-               case 't': return '\t';
-               case 'v': return '\v';
-               case 'x': /* TODO parse hex number ... */
-                       parse_error("hex escape sequences not implemented yet");
-                       return EOF;
-               case '0':
-               case '1':
-               case '2':
-               case '3':
-               case '4':
-               case '5':
-               case '6':
-               case '7':
-                       /* TODO parse octal number ... */
-                       parse_error("octal escape sequences not implemented yet");
-                       return EOF;
-               case '?':
-                       if(c != '?') {
-                               return '?';
-                       }
-                       /* might be a trigraph */
-                       next_char();
-                       if(replace_trigraph()) {
-                               break;
-                       }
-                       put_back(c);
-                       c = '?';
-                       return '?';
+       return value;
+}
 
-               case EOF:
-                       parse_error("reached end of file while parsing escape sequence");
-                       return EOF;
-               default:
-                       parse_error("unknown escape sequence");
-                       return EOF;
+static int parse_hex_sequence(void)
+{
+       int value = 0;
+       while(1) {
+               if (c >= '0' && c <= '9') {
+                       value = 16 * value + c - '0';
+               } else if ('A' <= c && c <= 'F') {
+                       value = 16 * value + c - 'A' + 10;
+               } else if ('a' <= c && c <= 'f') {
+                       value = 16 * value + c - 'a' + 10;
+               } else {
+                       break;
                }
+               next_char();
        }
+
+       return value;
 }
 
-static
-void parse_string_literal(token_t *token)
+static int parse_escape_sequence(void)
 {
-       unsigned    start_linenr = source_position.linenr;
+       eat('\\');
+
+       int ec = c;
+       next_char();
+
+       switch(ec) {
+       case '"':  return '"';
+       case '\'': return'\'';
+       case '\\': return '\\';
+       case '?': return '\?';
+       case 'a': return '\a';
+       case 'b': return '\b';
+       case 'f': return '\f';
+       case 'n': return '\n';
+       case 'r': return '\r';
+       case 't': return '\t';
+       case 'v': return '\v';
+       case 'x':
+               return parse_hex_sequence();
+       case '0':
+       case '1':
+       case '2':
+       case '3':
+       case '4':
+       case '5':
+       case '6':
+       case '7':
+               return parse_octal_sequence();
+       case EOF:
+               parse_error("reached end of file while parsing escape sequence");
+               return EOF;
+       default:
+               parse_error("unknown escape sequence");
+               return EOF;
+       }
+}
+
+const char *concat_strings(const char *s1, const char *s2)
+{
+       size_t  len1   = strlen(s1);
+       size_t  len2   = strlen(s2);
+
+       char   *concat = obstack_alloc(&symbol_obstack, len1 + len2 + 1);
+       memcpy(concat, s1, len1);
+       memcpy(concat + len1, s2, len2 + 1);
+
+       const char *result = strset_insert(&stringset, concat);
+       if(result != concat) {
+               obstack_free(&symbol_obstack, concat);
+       }
+
+       return result;
+}
+
+static void parse_string_literal(void)
+{
+       unsigned    start_linenr = lexer_token.source_position.linenr;
        char       *string;
        const char *result;
 
        assert(c == '"');
        next_char();
 
+       int tc;
        while(1) {
                switch(c) {
-               SKIP_TRIGRAPHS(,
-                       obstack_1grow(&symbol_obstack, '?');
-                       next_char();
-                       break;
-               )
-
                case '\\':
-                       next_char();
-                       EAT_NEWLINE(break;)
-                       int ec = parse_escape_sequence();
-                       obstack_1grow(&symbol_obstack, ec);
+                       tc = parse_escape_sequence();
+                       obstack_1grow(&symbol_obstack, tc);
                        break;
 
                case EOF:
-                       error_prefix_at(source_position.input_name, start_linenr);
+                       error_prefix_at(lexer_token.source_position.input_name,
+                                       start_linenr);
                        fprintf(stderr, "string has no end\n");
-                       token->type = T_ERROR;
+                       lexer_token.type = T_ERROR;
                        return;
 
                case '"':
@@ -459,41 +613,19 @@ end_of_string:
                obstack_free(&symbol_obstack, string);
        }
 
-       token->type     = T_STRING_LITERAL;
-       token->v.string = result;
+       lexer_token.type     = T_STRING_LITERAL;
+       lexer_token.v.string = result;
 }
 
-#define MATCH_NEWLINE(code)                 \
-       case '\r':                              \
-               next_char();                        \
-               if(c == '\n') {                     \
-                       next_char();                    \
-               }                                   \
-               source_position.linenr++;           \
-               code;                               \
-       case '\n':                              \
-               next_char();                        \
-               source_position.linenr++;           \
-               code;
-
-static
-void parse_character_constant(token_t *token)
+static void parse_character_constant(void)
 {
-       assert(c == '\'');
-       next_char();
+       eat('\'');
 
        int found_char = 0;
        while(1) {
                switch(c) {
-               SKIP_TRIGRAPHS(,
-                       found_char = '?';
-                       break;
-               )
-
                case '\\':
-                       next_char();
-                       EAT_NEWLINE(break;)
-                       found_char = '\\';
+                       found_char = parse_escape_sequence();
                        break;
 
                MATCH_NEWLINE(
@@ -507,7 +639,7 @@ void parse_character_constant(token_t *token)
 
                case EOF:
                        parse_error("EOF while parsing character constant");
-                       token->type = T_ERROR;
+                       lexer_token.type = T_ERROR;
                        return;
 
                default:
@@ -524,95 +656,48 @@ void parse_character_constant(token_t *token)
        }
 
 end_of_char_constant:
-       token->type       = T_INTEGER;
-       token->v.intvalue = found_char;
+       lexer_token.type       = T_INTEGER;
+       lexer_token.v.intvalue = found_char;
 }
 
-static
-void skip_multiline_comment(void)
+static void skip_multiline_comment(void)
 {
-       unsigned start_linenr = source_position.linenr;
-       int had_star = 0;
+       unsigned start_linenr = lexer_token.source_position.linenr;
 
        while(1) {
                switch(c) {
                case '*':
                        next_char();
-                       had_star = 1;
-                       break;
-
-               case '/':
-                       next_char();
-                       if(had_star) {
+                       if(c == '/') {
+                               next_char();
                                return;
                        }
-                       had_star = 0;
-                       break;
-
-               case '\\':
-                       next_char();
-                       EAT_NEWLINE(break;)
-                       had_star = 0;
-                       break;
-
-               case '?':
-                       next_char();
-                       if(c != '?') {
-                               had_star = 0;
-                               break;
-                       }
-                       next_char();
-                       if(replace_trigraph())
-                               break;
-                       put_back(c);
-                       c = '?';
-                       had_star = 0;
-                       /* we don't put back the 2nd ? as the comment text is discarded
-                        * anyway */
                        break;
 
-               MATCH_NEWLINE(had_star = 0; break;)
+               MATCH_NEWLINE(break;)
 
                case EOF:
-                       error_prefix_at(source_position.input_name, start_linenr);
+                       error_prefix_at(lexer_token.source_position.input_name,
+                                       start_linenr);
                        fprintf(stderr, "at end of file while looking for comment end\n");
                        return;
+
                default:
-                       had_star = 0;
                        next_char();
                        break;
                }
        }
 }
 
-static
-void skip_line_comment(void)
+static void skip_line_comment(void)
 {
        while(1) {
                switch(c) {
-               case '?':
-                       next_char();
-                       if(c != '?')
-                               break;
-                       next_char();
-                       if(replace_trigraph())
-                               break;
-                       put_back('?');
-                       /* we don't put back the 2nd ? as the comment text is discarded
-                        * anyway */
-                       break;
-
-               case '\\':
-                       next_char();
-                       if(c == '\n') {
-                               next_char();
-                               source_position.linenr++;
-                       }
-                       break;
-
                case EOF:
-               case '\r':
+                       return;
+
                case '\n':
+               case '\r':
                        return;
 
                default:
@@ -624,22 +709,20 @@ void skip_line_comment(void)
 
 static token_t pp_token;
 
-static inline
-void next_pp_token(void)
+static inline void next_pp_token(void)
 {
-       lexer_next_preprocessing_token(&pp_token);
+       lexer_next_preprocessing_token();
+       pp_token = lexer_token;
 }
 
-static
-void eat_until_newline(void)
+static void eat_until_newline(void)
 {
        while(pp_token.type != '\n' && pp_token.type != T_EOF) {
                next_pp_token();
        }
 }
 
-static
-void error_directive(void)
+static void error_directive(void)
 {
        error_prefix();
        fprintf(stderr, "#error directive: \n");
@@ -647,53 +730,45 @@ void error_directive(void)
        /* parse pp-tokens until new-line */
 }
 
-static
-void define_directive(void)
+static void define_directive(void)
 {
-       token_t temptoken;
-
-       lexer_next_preprocessing_token(&temptoken);
-       if(temptoken.type != T_IDENTIFIER) {
+       lexer_next_preprocessing_token();
+       if(lexer_token.type != T_IDENTIFIER) {
                parse_error("expected identifier after #define\n");
                eat_until_newline();
        }
 }
 
-static
-void ifdef_directive(int is_ifndef)
+static void ifdef_directive(int is_ifndef)
 {
        (void) is_ifndef;
-       token_t temptoken;
-       lexer_next_preprocessing_token(&temptoken);
+       lexer_next_preprocessing_token();
        //expect_identifier();
        //extect_newline();
 }
 
-static
-void endif_directive(void)
+static void endif_directive(void)
 {
        //expect_newline();
 }
 
-static
-void parse_line_directive(void)
+static void parse_line_directive(void)
 {
        if(pp_token.type != T_INTEGER) {
                parse_error("expected integer");
        } else {
-               source_position.linenr = pp_token.v.intvalue - 1;
+               lexer_token.source_position.linenr = pp_token.v.intvalue - 1;
                next_pp_token();
        }
        if(pp_token.type == T_STRING_LITERAL) {
-               source_position.input_name = pp_token.v.string;
+               lexer_token.source_position.input_name = pp_token.v.string;
                next_pp_token();
        }
 
        eat_until_newline();
 }
 
-static
-void parse_preprocessor_identifier(void)
+static void parse_preprocessor_identifier(void)
 {
        assert(pp_token.type == T_IDENTIFIER);
        symbol_t *symbol = pp_token.v.symbol;
@@ -730,8 +805,7 @@ void parse_preprocessor_identifier(void)
        }
 }
 
-static
-void parse_preprocessor_directive()
+static void parse_preprocessor_directive(void)
 {
        next_pp_token();
 
@@ -757,18 +831,10 @@ void parse_preprocessor_directive()
 #define MAYBE(ch, set_type)                                \
                                case ch:                                   \
                                        next_char();                           \
-                                       token->type = set_type;                \
+                                       lexer_token.type = set_type;           \
                                        return;
 
 #define ELSE_CODE(code)                                    \
-                               SKIP_TRIGRAPHS(,                           \
-                                       code;                                  \
-                               )                                          \
-                                                                                                                  \
-                               case '\\':                                 \
-                                       next_char();                           \
-                                       EAT_NEWLINE(break;)                    \
-                                       /* fallthrough */                      \
                                default:                                   \
                                        code;                                  \
                                }                                          \
@@ -777,11 +843,11 @@ void parse_preprocessor_directive()
 
 #define ELSE(set_type)                                     \
                ELSE_CODE(                                         \
-                       token->type = set_type;                        \
+                       lexer_token.type = set_type;                   \
                        return;                                        \
                )
 
-void lexer_next_preprocessing_token(token_t *token)
+void lexer_next_preprocessing_token(void)
 {
        while(1) {
                switch(c) {
@@ -791,36 +857,30 @@ void lexer_next_preprocessing_token(token_t *token)
                        break;
 
                MATCH_NEWLINE(
-                       token->type = '\n';
+                       lexer_token.type = '\n';
                        return;
                )
 
                SYMBOL_CHARS
-                       parse_symbol(token);
+                       parse_symbol();
+                       /* might be a wide string ( L"string" ) */
+                       if(c == '"' && (lexer_token.type == T_IDENTIFIER &&
+                          lexer_token.v.symbol == symbol_L)) {
+                               parse_string_literal();
+                               return;
+                       }
                        return;
 
                DIGITS
-                       parse_number(token);
+                       parse_number();
                        return;
 
                case '"':
-                       parse_string_literal(token);
+                       parse_string_literal();
                        return;
 
                case '\'':
-                       parse_character_constant(token);
-                       return;
-
-               case '\\':
-                       next_char();
-                       if(c == '\n') {
-                               next_char();
-                               source_position.linenr++;
-                               break;
-                       } else {
-                               parse_error("unexpected '\\' found");
-                               token->type = T_ERROR;
-                       }
+                       parse_character_constant();
                        return;
 
                case '.':
@@ -831,7 +891,7 @@ void lexer_next_preprocessing_token(token_t *token)
                                        ELSE_CODE(
                                                put_back(c);
                                                c = '.';
-                                               token->type = '.';
+                                               lexer_token.type = '.';
                                                return;
                                        )
                        ELSE('.')
@@ -851,6 +911,7 @@ void lexer_next_preprocessing_token(token_t *token)
                        ELSE('+')
                case '-':
                        MAYBE_PROLOG
+                       MAYBE('>', T_MINUSGREATER)
                        MAYBE('-', T_MINUSMINUS)
                        MAYBE('=', T_MINUSEQUAL)
                        ELSE('-')
@@ -864,12 +925,12 @@ void lexer_next_preprocessing_token(token_t *token)
                                case '*':
                                        next_char();
                                        skip_multiline_comment();
-                                       lexer_next_preprocessing_token(token);
+                                       lexer_next_preprocessing_token();
                                        return;
                                case '/':
                                        next_char();
                                        skip_line_comment();
-                                       lexer_next_preprocessing_token(token);
+                                       lexer_next_preprocessing_token();
                                        return;
                        ELSE('/')
                case '%':
@@ -884,7 +945,7 @@ void lexer_next_preprocessing_token(token_t *token)
                                                        ELSE_CODE(
                                                                put_back(c);
                                                                c = '%';
-                                                               token->type = T_PERCENTCOLON;
+                                                               lexer_token.type = T_PERCENTCOLON;
                                                                return;
                                                        )
                                        ELSE(T_PERCENTCOLON)
@@ -893,6 +954,7 @@ void lexer_next_preprocessing_token(token_t *token)
                        MAYBE_PROLOG
                        MAYBE(':', T_LESSCOLON)
                        MAYBE('%', T_LESSPERCENT)
+                       MAYBE('=', T_LESSEQUAL)
                                case '<':
                                        MAYBE_PROLOG
                                        MAYBE('=', T_LESSLESSEQUAL)
@@ -900,6 +962,7 @@ void lexer_next_preprocessing_token(token_t *token)
                        ELSE('<')
                case '>':
                        MAYBE_PROLOG
+                       MAYBE('=', T_GREATEREQUAL)
                                case '>':
                                        MAYBE_PROLOG
                                        MAYBE('=', T_GREATERGREATEREQUAL)
@@ -928,22 +991,6 @@ void lexer_next_preprocessing_token(token_t *token)
                        ELSE('#')
 
                case '?':
-                       next_char();
-                       /* just a simple ? */
-                       if(c != '?') {
-                               token->type = '?';
-                               return;
-                       }
-                       /* might be a trigraph */
-                       next_char();
-                       if(replace_trigraph()) {
-                               break;
-                       }
-                       put_back(c);
-                       c = '?';
-                       token->type = '?';
-                       return;
-
                case '[':
                case ']':
                case '(':
@@ -953,36 +1000,37 @@ void lexer_next_preprocessing_token(token_t *token)
                case '~':
                case ';':
                case ',':
-                       token->type = c;
+               case '\\':
+                       lexer_token.type = c;
                        next_char();
                        return;
 
                case EOF:
-                       token->type = T_EOF;
+                       lexer_token.type = T_EOF;
                        return;
 
                default:
                        next_char();
                        error_prefix();
                        fprintf(stderr, "unknown character '%c' found\n", c);
-                       token->type = T_ERROR;
+                       lexer_token.type = T_ERROR;
                        return;
                }
        }
 }
 
-void lexer_next_token(token_t *token)
+void lexer_next_token(void)
 {
-       lexer_next_preprocessing_token(token);
-       if(token->type != '\n')
+       lexer_next_preprocessing_token();
+       if(lexer_token.type != '\n')
                return;
 
 newline_found:
        do {
-               lexer_next_preprocessing_token(token);
-       } while(token->type == '\n');
+               lexer_next_preprocessing_token();
+       } while(lexer_token.type == '\n');
 
-       if(token->type == '#') {
+       if(lexer_token.type == '#') {
                parse_preprocessor_directive();
                goto newline_found;
        }
@@ -995,12 +1043,14 @@ void init_lexer(void)
 
 void lexer_open_stream(FILE *stream, const char *input_name)
 {
-       input                      = stream;
-       source_position.linenr     = 0;
-       source_position.input_name = input_name;
+       input                                  = stream;
+       lexer_token.source_position.linenr     = 0;
+       lexer_token.source_position.input_name = input_name;
+
+       symbol_L = symbol_table_insert("L");
 
-       /* we place a virtual '\n' at the beginning so the lexer knows we're at the
-        * beginning of a line */
+       /* place a virtual \n at the beginning so the lexer knows that we're
+        * at the beginning of a line */
        c = '\n';
 }
 
@@ -1012,6 +1062,7 @@ void exit_lexer(void)
 static __attribute__((unused))
 void dbg_pos(const source_position_t source_position)
 {
-       fprintf(stdout, "%s:%d\n", source_position.input_name, source_position.linenr);
+       fprintf(stdout, "%s:%d\n", source_position.input_name,
+               source_position.linenr);
        fflush(stdout);
 }