ref: 57ed804790202655d6ab2ee8f2dd3a6aac75b9b5
dir: /cc1/lex.c/
#include <errno.h> #include <inttypes.h> #include <setjmp.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <ctype.h> #include "../inc/sizes.h" #include "../inc/cc.h" #include "cc1.h" typedef struct input Input; struct input { char *fname; unsigned short nline; FILE *fp; char *line, *begin, *p; Symbol *macro; struct input *next; }; unsigned yytoken; struct yystype yylval; char yytext[IDENTSIZ + 1]; unsigned short yylen; int cppoff; static unsigned lex_ns = NS_IDEN; static int safe, eof, incomment; static Input *input; char * addinput(char *fname, Symbol *sym) { Input *ip; FILE *fp; unsigned short nline = 0; /* TODO: Add a field in input to see easier which is the case where we are */ if (fname) { if ((fp = fopen(fname, "r")) == NULL) return NULL; fname = xstrdup(fname); } else if (!input) { fp = stdin; fname = xstrdup("<stdin>"); } else { fname = input->fname; nline = input->nline; fp = NULL; } ip = xmalloc(sizeof(Input)); ip->fname = fname; ip->next = input; ip->macro = sym; ip->begin = ip->p = ip->line = xmalloc(INPUTSIZ); *ip->begin = '\0'; ip->nline = nline; ip->fp = fp; input = ip; return input->line; } static void delinput(void) { Input *ip = input; FILE *fp = ip->fp; if (!ip->next) eof = 1; if (fp) { if (fclose(fp)) die("error reading from input file '%s'", ip->fname); if (eof) return; free(ip->fname); } input = ip->next; free(ip->line); free(ip); } void setfname(char *name) { free(input->fname); input->fname = xstrdup(name); } char * getfname(void) { return input->fname; } void setfline(unsigned short line) { input->nline = line; } unsigned short getfline(void) { return input->nline; } static char readchar(void) { int c; FILE *fp; repeat: while (!input->fp || (feof(input->fp) && !eof)) delinput(); if (eof) { if (incomment) error("unterminated comment"); return '\0'; } fp = input->fp; if ((c = getc(fp)) == '\\') { if ((c = getc(fp)) == '\n') goto repeat; ungetc(c, fp); c = '\\'; } else if (c == EOF) { goto repeat; } else if (c == '\n' && ++input->nline == 0) { die("error:input file '%s' too long", getfname()); } return c; } static void comment(char c) { /* TODO: Ensure that incomment == 0 after a recovery */ incomment = 1; if (c == '*') { for (;;) { while (readchar() != '*') /* nothing */; if (readchar() == '/') break; } } else { while (readchar() != '\n') /* nothing */; } incomment = 0; } static void readline(void) { char *bp, *lim; char c, peekc = 0; lim = input->line + INPUTSIZ; 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 %u too big in file '%s'", getfline(), getfname()); *bp = '\0'; } bool moreinput(void) { char *p; repeat: if (eof) return 0; while (*input->begin == '\0' && !input->fp) { delinput(); if (*input->begin) return 1; } *(p = input->line) = '\0'; readline(); while (isspace(*p)) ++p; if (*p == '\0' || preprocessor(p) || cppoff) goto repeat; input->p = input->begin = 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'; fprintf(stderr ,"%s\n", yytext); 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; 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 buf[STRINGSIZ+1]; Symbol *sym; char *bp = buf, c; repeat: for (++input->p; (c = *input->p) != '\0' && c != '"'; ++input->p) { if (c == '\\') c = escape(); if (bp == &buf[STRINGSIZ]) error("string too long"); *bp++ = c; } if (c == '\0') error("missing terminating '\"' character"); input->begin = input->p + 1; if (ahead() == '"') goto repeat; *bp = '\0'; sym = newsym(NS_IDEN); sym->u.s = xstrdup(buf); sym->type = mktype(chartype, ARY, (bp - buf) + 1, NULL); yylval.sym = sym; return CONSTANT; } static unsigned iden(void) { char *p, *t, c; for (p = input->p; isalnum(*p) || *p == '_'; ++p) /* nothing */; input->p = p; tok2str(); yylval.sym = lookup(lex_ns); if (yylval.sym->ns == NS_CPP) { Symbol *sym; if (yylval.sym != input->macro && expand(yylval.sym)) return 0; /* * 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. */ p = yylval.sym->name; c = *p; for (sym = yylval.sym->hash; sym; sym = sym->hash) { t = sym->name; if (c == *t && !strcmp(p, t)) { yylval.sym = sym; goto found_iden; } } yylval.sym = install(lex_ns); yylval.sym->flags &= ~ISDEFINED; } found_iden: if (yylval.sym->token != IDEN) yylval.token = yylval.sym->u.token; return yylval.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) { char *p; repeat: for (p = input->begin; isspace(*p); ++p) /* nothing */; if (*p == '\0') { if (!moreinput()) return; goto repeat; } input->begin = input->p = p; } unsigned next(void) { char c; repeat: skipspaces(); if (eof) { strcpy(yytext, "<EOF>"); return yytoken = EOFTOK; } c = *input->begin; 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(); if (!yytoken) goto repeat; lex_ns = NS_IDEN; return yytoken; } void expect(unsigned tok) { if (yytoken != tok) { if (isgraph(tok)) softerror("expected '%c' before '%s'", tok, yytext); else softerror("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 (!moreinput()) exit(-1); } jump: yytoken = c; longjmp(recover, 1); }