/* * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands. * See the copyright notice in the ACK home directory, in the file "Copyright". */ /* $Id$ */ /* L E X I C A L A N A L Y Z E R */ #include #include "idfsize.h" #include "numsize.h" #include "strsize.h" #include #include "input.h" #include "idf.h" #include "LLlex.h" #include "Lpars.h" #include "class.h" #include "bits.h" /* Data about the token yielded */ struct token dot; int ReplaceMacros = 1; /* replacing macros */ int AccFileSpecifier = 0; /* return filespecifier <...> */ int AccDefined = 0; /* accept "defined(...)" */ int UnknownIdIsZero = 0; /* interpret unknown id as integer 0 */ void PushLex() { DOT = 0; } void PopLex() {} int LLlex() { return (DOT != EOF) ? GetToken(&dot) : EOF; } #ifdef BUFSIZ #undef BUFSIZ #endif #define BUFSIZ 1024 int GetToken(struct token *ptok) { char buf[BUFSIZ]; register int c, nch; again: /* rescan the input after an error or replacement */ LoadChar(c); if ((c & 0200) && c != EOI) fatal("non-ascii '\\%03o' read", c & 0377); switch (class(c)) { /* detect character class */ case STNL: LineNumber++; return ptok->tk_symb = EOF; case STSKIP: goto again; case STGARB: /* garbage character */ if (c == '\\') { /* a '\\' is allowed in #if/#elif expression */ LoadChar(c); if (class(c) == STNL) { /* vt , ff ? */ ++LineNumber; goto again; } PushBack(); c = '\\'; } if (040 < c && c < 0177) error("garbage char %c", c); else error("garbage char \\%03o", c); goto again; case STSIMP: /* a simple character, no part of compound token*/ if (c == '/') { /* probably the start of comment */ LoadChar(c); if (c == '*') { /* start of comment */ skipcomment(); goto again; } else { PushBack(); c = '/'; /* restore c */ } } return ptok->tk_symb = c; case STCOMP: /* maybe the start of a compound token */ LoadChar(nch); /* character lookahead */ switch (c) { case '!': if (nch == '=') return ptok->tk_symb = NOTEQUAL; PushBack(); return ptok->tk_symb = c; case '&': if (nch == '&') return ptok->tk_symb = AND; PushBack(); return ptok->tk_symb = c; case '<': if (AccFileSpecifier) { PushBack(); /* pushback nch */ ptok->tk_str = string_token("file specifier", '>'); return ptok->tk_symb = FILESPECIFIER; } if (nch == '<') return ptok->tk_symb = LEFT; if (nch == '=') return ptok->tk_symb = LESSEQ; PushBack(); return ptok->tk_symb = c; case '=': if (nch != '=') { PushBack(); error("missing ="); } return ptok->tk_symb = EQUAL; case '>': if (nch == '=') return ptok->tk_symb = GREATEREQ; if (nch == '>') return ptok->tk_symb = RIGHT; PushBack(); return ptok->tk_symb = c; case '|': if (nch == '|') return ptok->tk_symb = OR; PushBack(); return ptok->tk_symb = c; } case STIDF: { extern int idfsize; /* ??? */ register char *tg = &buf[0]; register char *maxpos = &buf[idfsize]; register struct idf *idef; #define tstmac(bx) if (!(bits[c] & bx)) goto nomac #define cpy if (Unstacked) EnableMacros(); *tg++ = c #define load LoadChar(c); if (!in_idf(c)) goto endidf #ifdef DOBITS cpy; tstmac(bit0); load; cpy; tstmac(bit1); load; cpy; tstmac(bit2); load; cpy; tstmac(bit3); load; cpy; tstmac(bit4); load; cpy; tstmac(bit5); load; cpy; tstmac(bit6); load; cpy; tstmac(bit7); load; #endif for(;;) { if (tg < maxpos) { cpy; } load; } endidf: PushBack(); *tg = '\0'; /* mark the end of the identifier */ if (ReplaceMacros) { idef = findidf(buf); if ((idef && idef->id_macro && replace(idef))) { goto again; } } nomac: LoadChar(c); while (in_idf(c)) { if (tg < maxpos) *tg++ = c; LoadChar(c); } PushBack(); *tg++ = '\0'; /* mark the end of the identifier */ if (UnknownIdIsZero) { ptok->tk_val = 0; return ptok->tk_symb = INTEGER; } ptok->tk_str = Malloc(tg - buf); strcpy(ptok->tk_str, buf); return ptok->tk_symb = IDENTIFIER; } case STCHAR: /* character constant */ { register arith val = 0; register int size = 0; LoadChar(c); if (c == '\'') error("character constant too short"); else while (c != '\'') { if (c == '\n') { error("newline in character constant"); PushBack(); break; } if (c == '\\') { LoadChar(c); if (c == '\n') { LineNumber++; } c = quoted(c); } if (c >= 128) c -= 256; val = val*256 + c; size++; LoadChar(c); } if (size > sizeof(arith)) error("character constant too long"); ptok->tk_val = val; return ptok->tk_symb = INTEGER; } case STNUM: { register char *np = &buf[1]; register int base = 10; register int vch; register arith val = 0; if (c == '0') { *np++ = c; LoadChar(c); if (c == 'x' || c == 'X') { base = 16; LoadChar(c); } else base = 8; } while (vch = val_in_base(c, base), vch >= 0) { val = val*base + vch; if (np < &buf[NUMSIZE]) *np++ = c; LoadChar(c); } if (c == 'l' || c == 'L') LoadChar(c); PushBack(); ptok->tk_val = val; return ptok->tk_symb = INTEGER; } case STSTR: ptok->tk_str = string_token("string", '"'); return ptok->tk_symb = STRING; case STEOI: /* end of text on source file */ return ptok->tk_symb = EOF; default: crash("Impossible character class"); } /*NOTREACHED*/ return 0; } void skipcomment() { register int c; NoUnstack++; LoadChar(c); do { while (c != '*') { if (class(c) == STNL) ++LineNumber; else if (c == EOI) { NoUnstack--; return; } LoadChar(c); } /* Last Character seen was '*' */ LoadChar(c); } while (c != '/'); NoUnstack--; } char *string_token(char *nm, int stop_char) { register int c; register unsigned int str_size; register char *str = Malloc(str_size = ISTRSIZE); register int pos = 0; LoadChar(c); while (c != stop_char) { if (c == '\n') { error("newline in %s", nm); PushBack(); break; } if (c == EOI) { error("end-of-file inside %s", nm); break; } if (c == '\\') { LoadChar(c); if (c == '\n') { LineNumber++; LoadChar(c); continue; } c = quoted(c); } str[pos++] = c; if (pos == str_size) str = Realloc(str, str_size <<= 1); LoadChar(c); } str[pos++] = '\0'; /* for filenames etc. */ str = Realloc(str, pos); return str; } int quoted(int c) { /* quoted() replaces an escaped character sequence by the character meant. */ /* first char after backslash already in c */ if (!is_oct(c)) { /* a quoted char */ switch (c) { case 'n': c = '\n'; break; case 't': c = '\t'; break; case 'b': c = '\b'; break; case 'r': c = '\r'; break; case 'f': c = '\f'; break; } } else { /* a quoted octal */ register int oct = 0, cnt = 0; do { oct = oct*8 + (c-'0'); LoadChar(c); } while (is_oct(c) && ++cnt < 3); PushBack(); c = oct; } return c&0377; } /* provisional */ int val_in_base(int c, int base) { return is_dig(c) ? c - '0' : base != 16 ? -1 : is_hex(c) ? (c - 'a' + 10) & 017 : -1; }