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Text File | 1995-09-08 | 3.4 KB | 179 lines | [TEXT/MPS ] |
- // $Log: scanner.re,v $
- //Revision 1.1 1994/04/08 15:27:59 peter
- //Initial revision
- //
-
- #include <stdlib.h>
- #include <string.h>
- #include <iostream.h>
- #include <unistd.h>
- #include "scanner.h"
- #include "parser.h"
- #include "y.tab.h"
-
- extern YYSTYPE yylval;
-
- #define BSIZE 8192
-
- #define YYCTYPE uchar
- #define YYCURSOR cursor
- #define YYLIMIT lim
- #define YYMARKER ptr
- #define YYFILL(n) {cursor = fill(cursor);}
-
- #define RETURN(i) {cur = cursor; return i;}
-
-
- Scanner::Scanner(int i) : in(i),
- bot(NULL), tok(NULL), ptr(NULL), cur(NULL), pos(NULL), lim(NULL),
- top(NULL), eof(NULL), tchar(0), tline(0), cline(1) {
- ;
- }
-
- uchar *Scanner::fill(uchar *cursor){
- if(!eof){
- uint cnt = tok - bot;
- if(cnt){
- memcpy(bot, tok, lim - tok);
- tok = bot;
- ptr -= cnt;
- cursor -= cnt;
- pos -= cnt;
- lim -= cnt;
- }
- if((top - lim) < BSIZE){
- uchar *buf = new uchar[(lim - bot) + BSIZE];
- memcpy(buf, tok, lim - tok);
- tok = buf;
- ptr = &buf[ptr - bot];
- cursor = &buf[cursor - bot];
- pos = &buf[pos - bot];
- lim = &buf[lim - bot];
- top = &lim[BSIZE];
- delete bot;
- bot = buf;
- }
- if((cnt = read(in, (char*) lim, BSIZE)) != BSIZE){
- eof = &lim[cnt]; *eof++ = '\n';
- }
- lim += cnt;
- }
- return cursor;
- }
-
- /*!re2c
- any = [\000-\377];
- dot = any \ [\n];
- esc = dot \ [\\];
- cstring = "[" ((esc \ [\]]) | "\\" dot)* "]" ;
- dstring = "\"" ((esc \ ["] ) | "\\" dot)* "\"";
- sstring = "'" ((esc \ ['] ) | "\\" dot)* "'" ;
- letter = [a-zA-Z];
- digit = [0-9];
- */
-
- int Scanner::echo(ostream &out){
- uchar *cursor = cur;
- tok = cursor;
- echo:
- /*!re2c
- "/*!re2c" { out.write(tok, &cursor[-7] - tok);
- tok = cursor;
- RETURN(1); }
- "\n" { if(cursor == eof) RETURN(0);
- out.write(tok, cursor - tok);
- tok = pos = cursor; cline++;
- goto echo; }
- any { goto echo; }
- */
- }
-
-
- int Scanner::scan(){
- uchar *cursor = cur;
- uint depth;
-
- scan:
- tchar = cursor - pos;
- tline = cline;
- tok = cursor;
- /*!re2c
- "{" { depth = 1;
- goto code;
- }
- "/*" { depth = 1;
- goto comment; }
-
- "*/" { tok = cursor;
- RETURN(0); }
-
- dstring { cur = cursor;
- yylval.regexp = strToRE(token());
- return STRING; }
- "\"" { fatal("bad string"); }
-
- cstring { cur = cursor;
- yylval.regexp = ranToRE(token());
- return RANGE; }
- "[" { fatal("bad character constant"); }
-
- [()|=;/\\] { RETURN(*tok); }
-
- [*+?] { yylval.op = *tok;
- RETURN(CLOSE); }
-
- letter (letter|digit)* { cur = cursor;
- yylval.symbol = Symbol::find(token());
- return ID; }
-
- [ \t]+ { goto scan; }
-
- "\n" { if(cursor == eof) RETURN(0);
- pos = cursor; cline++;
- goto scan;
- }
-
- any { cerr << "unexpected character: " << *tok << endl;
- goto scan;
- }
- */
-
- code:
- /*!re2c
- "}" { if(--depth == 0){
- cur = cursor;
- yylval.token = new Token(token(), tline);
- return CODE;
- }
- goto code; }
- "{" { ++depth;
- goto code; }
- "\n" { if(cursor == eof) fatal("missing '}'");
- pos = cursor; cline++;
- goto code;
- }
- dstring | sstring | any { goto code; }
- */
-
- comment:
- /*!re2c
- "*/" { if(--depth == 0)
- goto scan;
- else
- goto comment; }
- "/*" { ++depth;
- goto comment; }
- "\n" { if(cursor == eof) RETURN(0);
- tok = pos = cursor; cline++;
- goto comment;
- }
- any { goto comment; }
- */
- }
-
- void Scanner::fatal(char *msg){
- cerr << "line " << tline << ", column " << (tchar + 1) << ": "
- << msg << endl;
- exit(1);
- }
-