ref: cde67f41cb37d1c695d7de0a5100458bcc5de9c1
dir: /cc1/lex.c/
#include <ctype.h> #include <errno.h> #include <inttypes.h> #include <setjmp.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include "../inc/sizes.h" #include "../inc/cc.h" #include "cc1.h" unsigned yytoken; struct yystype yylval; char yytext[STRINGSIZ+3]; unsigned short yylen; int cppoff; int lexmode = CCMODE; static unsigned lex_ns = NS_IDEN; static int safe, eof; Input *input; static void allocinput(char *fname, FILE *fp) { Input *ip; ip = xmalloc(sizeof(Input)); ip->fname = xstrdup(fname); ip->p = ip->begin = ip->line = xmalloc(INPUTSIZ); ip->nline = 0; ip->next = input; ip->fp = fp; input = ip; } void ilex(char *fname) { FILE *fp; if (!fname) { fp = stdin; fname = "<stdin>"; } else { if ((fp = fopen(fname, "r")) == NULL) die("error opening output:%s", strerror(errno)); fname = fname; } allocinput(fname, fp); *input->begin = '\0'; } bool addinput(char *fname) { FILE *fp; if ((fp = fopen(fname, "r")) == NULL) return 0; allocinput(fname, fp); return 1; } static void delinput(void) { Input *ip = input; if (!ip->next) eof = 1; if (fclose(ip->fp)) die("error reading from input file '%s'", ip->fname); if (eof) return; input = ip->next; free(ip->fname); free(ip->line); } static void newline(void) { if (++input->nline == 0) die("error:input file '%s' too long", input->fname); } static char readchar(void) { int c; FILE *fp; repeat: fp = input->fp; switch (c = getc(fp)) { case EOF: c = '\0'; break; case '\\': if ((c = getc(fp)) == '\n') { newline(); goto repeat; } ungetc(c, fp); c = '\\'; break; case '\n': newline(); break; } return c; } static void comment(char type) { if (type == '*') { while (!eof) { while (readchar() != '*' && !eof) /* nothing */; if (readchar() == '/') break; } } else { while (readchar() != '\n' && !eof) /* nothing */; } if (eof) error("unterminated comment"); } static bool readline(void) { char *bp, *lim; char c, peekc = 0; repeat: input->begin = input->p = input->line; *input->line = '\0'; if (eof) return 0; if (feof(input->fp)) { delinput(); goto repeat; } lim = &input->line[INPUTSIZ-1]; for (bp = input->line; bp < lim; *bp++ = c) { c = (peekc) ? peekc : readchar(); peekc = 0; if (c == '\n' || c == '\0') break; if (c != '/') continue; if ((c = readchar()) != '*' && c != '/') { peekc = c; c = '/'; } else { comment(c); c = ' '; } } if (bp == lim) error("line too long"); *bp = '\0'; return 1; } bool moreinput(void) { repeat: if (!readline()) return 0; while (isspace(*input->p)) ++input->p; input->begin = input->p; if (*input->p == '\0' || cpp() || cppoff) { *input->begin = '\0'; goto repeat; } input->begin = input->p; return 1; } static void tok2str(void) { if ((yylen = input->p - input->begin) > IDENTSIZ) error("token too big"); strncpy(yytext, input->begin, yylen); yytext[yylen] = '\0'; input->begin = input->p; } static unsigned integer(char *s, char base) { Type *tp; Symbol *sym; unsigned size, sign; long v; for (size = sign = 0; ; ++input->p) { switch (toupper(*input->p)) { case 'L': if (size == LLONG) goto wrong_type; size = (size == LONG) ? LLONG : LONG; continue; case 'U': if (sign == UNSIGNED) goto wrong_type; sign = UNSIGNED; continue; default: goto convert; wrong_type: error("invalid suffix in integer constant"); } } convert: tp = ctype(INT, sign, size); sym = newsym(NS_IDEN); sym->type = tp; sym->flags |= ISCONSTANT; v = strtol(s, NULL, base); if (tp == inttype) sym->u.i = v; yylval.sym = sym; return CONSTANT; } static char * digits(unsigned base) { char c, *p; for (p = input->p; c = *p; ++p) { switch (base) { case 8: if (c > '7' || c < '0') goto end; break; case 10: if (!isdigit(c)) goto end; break; case 16: if (!isxdigit(c)) goto end; break; } } end: input->p = p; tok2str(); return yytext; } static unsigned number(void) { char base; if (*input->p != '0') { base = 10; } else { if (toupper(*++input->p) == 'X') { ++input->p; base = 16; } else { base = 8; } } return integer(digits(base), base); } static char escape(void) { int c, base; ++input->p; switch (*input->p++) { case '\\': return '\\'; case 'a': return '\a'; case 'f': return '\f'; case 'n': return '\n'; case 'r': return '\r'; case 't': return '\t'; case 'v': return '\v'; case '\'': return '\\'; case '"': return'"'; case '?': return '?'; case 'u': base = 10; break; case 'x': base = 16; break; case '0': base = 8; break; default: warn("unknown escape sequence"); return ' '; } errno = 0; c = strtoul(input->p, &input->p, base); if (errno || c > 255) warn("character constant out of range"); return c; } static unsigned character(void) { static char c; Symbol *sym; if ((c = *++input->p) == '\\') c = escape(); if (*input->p != '\'') error("invalid character constant"); ++input->p; sym = newsym(NS_IDEN); sym->u.i = c; sym->type = inttype; yylval.sym = sym; return CONSTANT; } static unsigned string(void) { char *bp = yytext, c; *bp++ = '"'; repeat: for (++input->p; (c = *input->p) != '"'; ++input->p) { if (c == '\0') error("missing terminating '\"' character"); if (c == '\\') c = escape(); if (bp == &yytext[STRINGSIZ+1]) error("string too long"); *bp++ = c; } input->begin = ++input->p; if (ahead() == '"') goto repeat; *bp = '\0'; yylen = bp - yytext + 1; yylval.sym = newsym(NS_IDEN); yylval.sym->flags |= ISCONSTANT; yylval.sym->u.s = xstrdup(yytext+1); yylval.sym->type = mktype(chartype, ARY, yylen - 2, NULL); *bp++ = '"'; *bp = '\0'; return CONSTANT; } static unsigned iden(void) { Symbol *sym; char *p, *begin; begin = input->p; for (p = begin; isalnum(*p) || *p == '_'; ++p) /* nothing */; input->p = p; tok2str(); yylval.sym = sym = lookup(lex_ns); if (sym->ns == NS_CPP) { if (!disexpand && expand(begin, sym)) return next(); /* * it is not a correct macro call, so try to find * another definition. This is going to be expensive * but I think it is not going to be a common case. */ sym = nextsym(sym, lex_ns); } if (sym->flags & ISCONSTANT) return CONSTANT; if (sym->token != IDEN) yylval.token = sym->u.token; return sym->token; } static unsigned follow(int expect, int ifyes, int ifno) { if (*input->p++ == expect) return ifyes; --input->p; return ifno; } static unsigned minus(void) { switch (*input->p++) { case '-': return DEC; case '>': return INDIR; case '=': return SUB_EQ; default: --input->p; return '-'; } } static unsigned plus(void) { switch (*input->p++) { case '+': return INC; case '=': return ADD_EQ; default: --input->p; return '+'; } } static unsigned relational(int op, int equal, int shift, int assig) { char c; if ((c = *input->p++) == '=') return equal; if (c == op) return follow('=', assig, shift); --input->p; return op; } static unsigned logic(int op, int equal, int logic) { char c; if ((c = *input->p++) == equal) return equal; if (c == op) return logic; --input->p; return op; } static unsigned dot(void) { char c; if ((c = *input->p) != '.') return '.'; if ((c = *++input->p) != '.') error("incorrect token '..'"); ++input->p; return ELLIPSIS; } static unsigned operator(void) { unsigned t; switch (t = *input->p++) { case '<': t = relational('<', LE, SHL, SHL_EQ); break; case '>': t = relational('>', GE, SHR, SHR_EQ); break; case '&': t = logic('&', AND_EQ, AND); break; case '|': t = logic('|', OR_EQ, OR); break; case '=': t = follow('=', EQ, '='); break; case '^': t = follow('=', XOR_EQ, '^'); break; case '*': t = follow('=', MUL_EQ, '*'); break; case '/': t = follow('=', DIV_EQ, '/'); break; case '!': t = follow('=', NE, '!'); break; case '-': t = minus(); break; case '+': t = plus(); break; case '.': t = dot(); break; } tok2str(); return t; } /* TODO: Ensure that lex_ns is NS_IDEN after a recovery */ void setnamespace(int ns) { lex_ns = ns; } static void skipspaces(void) { repeat: while (isspace(*input->p)) ++input->p; if (*input->p == '\0' && lexmode != CPPMODE) { if (!moreinput()) return; goto repeat; } input->begin = input->p; } unsigned next(void) { char c; skipspaces(); c = *input->begin; if ((eof || lexmode == CPPMODE) && c == '\0') { strcpy(yytext, "<EOF>"); if (cppctx && eof) error("#endif expected"); yytoken = EOFTOK; goto exit; } if (isalpha(c) || c == '_') yytoken = iden(); else if (isdigit(c)) yytoken = number(); else if (c == '"') yytoken = string(); else if (c == '\'') yytoken = character(); else yytoken = operator(); exit: fprintf(stderr, "TOKEN %s\n", yytext); lex_ns = NS_IDEN; return yytoken; } void expect(unsigned tok) { if (yytoken != tok) { if (isgraph(tok)) printerr("expected '%c' before '%s'", tok, yytext); else printerr("unexpected '%s'", yytext); } else { next(); } } char ahead(void) { skipspaces(); return *input->begin; } void setsafe(int type) { safe = type; } void discard(void) { extern jmp_buf recover; char c; input->begin = input->p; for (c = yytoken; ; c = *input->begin++) { switch (safe) { case END_COMP: if (c == '}') goto jump; goto semicolon; case END_COND: if (c == ')') goto jump; break; case END_LDECL: if (c == ',') goto jump; case END_DECL: semicolon: if (c == ';') goto jump; break; } if (c == '\0' && !moreinput()) exit(1); } jump: yytoken = c; longjmp(recover, 1); }