ref: 727425772ef17fe710453ab97f659b82b8a6b585
dir: /src/cmd/cc/cc1/cpp.c/
#include <ctype.h> #include <limits.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> #include <scc/cstd.h> #include <scc/scc.h> #include "cc1.h" static char *argp, *macroname; static unsigned arglen; static unsigned ncmdlines; static Symbol *symline, *symfile; static unsigned char ifstatus[NR_COND]; static int cppoff; static struct items dirinclude; unsigned cppctx; int disexpand; void defdefine(char *macro, char *val, char *source) { char *def, *fmt = "#define %s %s\n"; Symbol dummy = {.flags = SDECLARED}; if (!val) val = ""; def = xmalloc(strlen(fmt) + strlen(macro) + strlen(val)); sprintf(def, fmt, macro, val); lineno = ++ncmdlines; addinput(source, &dummy, def); cpp(); delinput(); } void undefmacro(char *s) { killsym(lookup(NS_CPP, s, NOALLOC)); } void icpp(void) { static char sdate[14], stime[11]; struct tm *tm; time_t t; static char **bp, *list[] = { "__STDC__", "__STDC_HOSTED__", "__SCC__", NULL }; static struct keyword keys[] = { {"define", DEFINE, DEFINE}, {"include", INCLUDE, INCLUDE}, {"line", LINE, LINE}, {"ifdef", IFDEF, IFDEF}, {"if", IF, IF}, {"elif", ELIF, ELIF}, {"else", ELSE, ELSE}, {"ifndef", IFNDEF, IFNDEF}, {"endif", ENDIF, ENDIF}, {"undef", UNDEF, UNDEF}, {"pragma", PRAGMA, PRAGMA}, {"error", ERROR, ERROR}, {NULL, 0, 0} }; keywords(keys, NS_CPPCLAUSES); t = time(NULL); tm = localtime(&t); strftime(sdate, sizeof(sdate), "\"%b %d %Y\"", tm); strftime(stime, sizeof(stime), "\"%H:%M:%S\"", tm); defdefine("__DATE__", sdate, "built-in"); defdefine("__TIME__", stime, "built-in"); defdefine("__STDC_VERSION__", STDC_VERSION, "built-in"); defdefine("__LINE__", NULL, "built-in"); defdefine("__FILE__", NULL, "built-in"); symline = lookup(NS_CPP, "__LINE__", ALLOC); symfile = lookup(NS_CPP, "__FILE__", ALLOC); for (bp = list; *bp; ++bp) defdefine(*bp, "1", "built-in"); ncmdlines = 0; } static void nextcpp(void) { next(); if (yytoken == EOFTOK) error("unterminated argument list invoking macro \"%s\"", macroname); if (yylen + 1 > arglen) error("argument overflow invoking macro \"%s\"", macroname); if (yytoken == IDEN) yylval.sym->flags |= SUSED; memcpy(argp, yytext, yylen); argp += yylen; *argp++ = ' '; arglen -= yylen + 1; } static void paren(void) { for (;;) { nextcpp(); switch (yytoken) { case ')': return; case '(': paren(); break; } } } static void parameter(void) { for (;;) { nextcpp(); switch (yytoken) { case ')': case ',': argp -= 3; /* remove " , " or " ) "*/ *argp++ = '\0'; return; case '(': paren(); break; } } } static int parsepars(char *buffer, char **listp, int nargs) { int n; if (nargs == -1) return -1; if (ahead() != '(' && nargs > 0) return 0; disexpand = 1; next(); n = 0; argp = buffer; arglen = INPUTSIZ; if (ahead() == ')') { next(); } else { do { *listp++ = argp; parameter(); } while (++n < NR_MACROARG && yytoken == ','); } if (yytoken != ')') error("incorrect macro function-alike invocation"); disexpand = 0; if (n == NR_MACROARG) error("too many parameters in macro \"%s\"", macroname); if (n != nargs) { error("macro \"%s\" received %d arguments, but it takes %d", macroname, n, nargs); } return 1; } static size_t copymacro(char *buffer, char *s, size_t bufsiz, char *arglist[]) { int delim, prevc, c; char *p, *arg, *bp = buffer; size_t size; for (prevc = '\0'; c = *s; prevc = c, ++s) { switch (c) { case '$': while (bp[-1] == ' ') --bp, ++bufsiz; while (s[1] == ' ') ++s; case '#': break; case '\'': delim = '\''; goto search_delim; case '\"': delim = '"'; search_delim: for (p = s; *++s != delim; ) ; size = s - p + 1; if (size > bufsiz) goto expansion_too_long; memcpy(bp, p, size); bufsiz -= size; bp += size; break; case '@': if (prevc == '#') bufsiz -= 2; arg = arglist[atoi(++s)]; size = strlen(arg); if (size > bufsiz) goto expansion_too_long; if (prevc == '#') *bp++ = '"'; memcpy(bp, arg, size); bp += size; if (prevc == '#') *bp++ = '"'; bufsiz -= size; s += 2; break; default: if (bufsiz-- == 0) goto expansion_too_long; *bp++ = c; break; } } *bp = '\0'; return bp - buffer; expansion_too_long: error("macro expansion of \"%s\" too long", macroname); } int expand(char *begin, Symbol *sym) { size_t elen; int n, i; char *s = sym->u.s; char *arglist[NR_MACROARG], arguments[INPUTSIZ], buffer[INPUTSIZ]; macroname = sym->name; if (sym == symfile) { elen = sprintf(buffer, "\"%s\" ", filenam); goto substitute; } if (sym == symline) { elen = sprintf(buffer, "%d ", lineno); goto substitute; } if (!s) return 1; n = atoi(s); if (!parsepars(arguments, arglist, n)) return 0; for (i = 0; i < n; ++i) DBG("MACRO par%d:%s", i, arglist[i]); elen = copymacro(buffer, s+3, INPUTSIZ-1, arglist); substitute: DBG("MACRO '%s' expanded to :'%s'", macroname, buffer); buffer[elen] = '\0'; addinput(filenam, sym, xstrdup(buffer)); return 1; } static int getpars(Symbol *args[NR_MACROARG]) { int n, c; Symbol *sym; c = *input->p; next(); if (c != '(') return -1; next(); /* skip the '(' */ if (accept(')')) return 0; n = 0; do { if (n == NR_MACROARG) { cpperror("too many parameters in macro"); return NR_MACROARG; } if (accept(ELLIPSIS)) { args[n++] = NULL; break; } if (yytoken != IDEN) { cpperror("macro arguments must be identifiers"); return NR_MACROARG; } sym = install(NS_IDEN, yylval.sym); sym->flags |= SUSED; args[n++] = sym; next(); } while (accept(',')); expect(')'); return n; } static int getdefs(Symbol *args[NR_MACROARG], int nargs, char *bp, size_t bufsiz) { Symbol **argp; size_t len; int prevc = 0, ispar; if (yytoken == '$') { cpperror("'##' cannot appear at either ends of a macro expansion"); return 0; } for (;;) { ispar = 0; if (yytoken == IDEN && nargs >= 0) { for (argp = args; argp < &args[nargs]; ++argp) { if (*argp == yylval.sym) break; } if (argp != &args[nargs]) { sprintf(yytext, "@%02d@", (int) (argp - args)); ispar = 1; } } if (prevc == '#' && !ispar) { cpperror("'#' is not followed by a macro parameter"); return 0; } if (yytoken == '\n') break; if ((len = strlen(yytext)) >= bufsiz) { cpperror("macro too long"); return 0; } if (yytoken == '$') { *bp++ = '$'; --bufsiz; } else { memcpy(bp, yytext, len); bp += len; bufsiz -= len; } if ((prevc = yytoken) != '#') { *bp++ = ' '; --bufsiz; } next(); } *bp = '\0'; return 1; } static void define(void) { Symbol *sym,*args[NR_MACROARG]; char buff[LINESIZ+1]; int n; if (cppoff) return; namespace = NS_CPP; next(); if (yytoken != IDEN) { cpperror("macro names must be identifiers"); return; } sym = yylval.sym; if (sym->flags & SDECLARED) { warn("'%s' redefined", yytext); free(sym->u.s); } else { sym = install(NS_CPP, sym); sym->flags |= SDECLARED|SSTRING; } namespace = NS_IDEN; /* Avoid polution in NS_CPP */ if ((n = getpars(args)) == NR_MACROARG) goto delete; if (n > 0 && !args[n-1]) /* it is a variadic function */ --n; sprintf(buff, "%02d#", n); if (!getdefs(args, n, buff+3, LINESIZ-3)) goto delete; sym->u.s = xstrdup(buff); DBG("MACRO '%s' defined as '%s'", sym->name, buff); return; delete: killsym(sym); } void incdir(char *dir) { if (!dir || *dir == '\0') die("cc1: incorrect -I flag"); newitem(&dirinclude, dir); } static int includefile(char *dir, char *file, size_t filelen) { size_t dirlen; char path[FILENAME_MAX]; if (!dir) { dirlen = 0; if (filelen > FILENAME_MAX-1) return 0; } else { dirlen = strlen(dir); if (dirlen + filelen > FILENAME_MAX-2) return 0; memcpy(path, dir, dirlen); if (dir[dirlen-1] != '/') path[dirlen++] = '/'; } memcpy(path+dirlen, file, filelen); path[dirlen + filelen] = '\0'; addinput(path, NULL, NULL); return 1; } static char * cwd(char *buf) { char *p, *s = filenam; size_t len; if ((p = strrchr(s, '/')) == NULL) return NULL; if ((len = p - s) >= FILENAME_MAX) die("cc1: current work directory too long"); memcpy(buf, s, len); buf[len] = '\0'; return buf; } static void include(void) { char dir[FILENAME_MAX], file[FILENAME_MAX], *p, **bp; size_t filelen; int n; if (cppoff) return; namespace = NS_IDEN; next(); switch (*yytext) { case '<': if ((p = strchr(input->begin, '>')) == NULL || p[-1] == '<') goto bad_include; filelen = p - input->begin; if (filelen >= FILENAME_MAX) goto too_long; memcpy(file, input->begin, filelen); file[filelen] = '\0'; input->begin = input->p = p+1; if (next() != '\n') goto trailing_characters; break; case '"': if (yylen < 3) goto bad_include; filelen = yylen-2; if (filelen >= FILENAME_MAX) goto too_long; memcpy(file, yytext+1, filelen); file[filelen] = '\0'; if (next() != '\n') goto trailing_characters; if (includefile(cwd(dir), file, filelen)) goto its_done; break; default: goto bad_include; } n = dirinclude.n; for (bp = dirinclude.s; n--; ++bp) { if (includefile(*bp, file, filelen)) goto its_done; } cpperror("included file '%s' not found", file); its_done: return; trailing_characters: cpperror("trailing characters after preprocessor directive"); return; too_long: cpperror("too long file name in #include"); return; bad_include: cpperror("#include expects \"FILENAME\" or <FILENAME>"); return; } static void line(void) { long n; char *endp, *fname; if (cppoff) return; disexpand = 0; next(); n = strtol(yytext, &endp, 10); if (n <= 0 || n > USHRT_MAX || *endp != '\0') { cpperror("first parameter of #line is not a positive integer"); return; } next(); if (yytoken == '\n') { fname = NULL; } else { if (*yytext != '\"' || yylen == 1) { cpperror("second parameter of #line is not a valid filename"); return; } fname = yylval.sym->u.s; } setloc(fname, n - 1); if (yytoken != '\n') next(); } static void pragma(void) { if (cppoff) return; next(); warn("ignoring pragma '%s'", yytext); *input->p = '\0'; next(); } static void usererr(void) { if (cppoff) return; cpperror("#error %s", input->p); *input->p = '\0'; next(); } static void ifclause(int negate, int isifdef) { Symbol *sym; unsigned n; int status; Node *expr; if (cppctx == NR_COND-1) error("too many nesting levels of conditional inclusion"); n = cppctx++; namespace = NS_CPP; next(); if (isifdef) { if (yytoken != IDEN) { cpperror("no macro name given in #%s directive", (negate) ? "ifndef" : "ifdef"); return; } sym = yylval.sym; next(); status = (sym->flags & SDECLARED) != 0; if (!status) killsym(sym); } else { /* TODO: catch recovery here */ if ((expr = constexpr()) == NULL) { cpperror("parameter of #if is not an integer constant expression"); return; } status = expr->sym->u.i != 0; freetree(expr); } if (negate) status = !status; if ((ifstatus[n] = status) == 0) ++cppoff; } static void cppif(void) { disexpand = 0; ifclause(0, 0); } static void ifdef(void) { ifclause(0, 1); } static void ifndef(void) { ifclause(1, 1); } static void elseclause(void) { int status; if (cppctx == 0) { cpperror("#else without #ifdef/ifndef"); return; } status = ifstatus[cppctx-1]; ifstatus[cppctx-1] = !status; cppoff += (status) ? 1 : -1; } static void cppelse(void) { elseclause(); next(); } static void elif(void) { elseclause(); if (ifstatus[cppctx-1]) { --cppctx; cppif(); } } static void endif(void) { if (cppctx == 0) error("#endif without #if"); if (!ifstatus[--cppctx]) --cppoff; next(); } static void undef(void) { if (cppoff) return; namespace = NS_CPP; next(); if (yytoken != IDEN) { error("no macro name given in #undef directive"); return; } killsym(yylval.sym); next(); } int cpp(void) { static struct { unsigned char token; void (*fun)(void); } *bp, clauses [] = { {DEFINE, define}, {INCLUDE, include}, {LINE, line}, {IFDEF, ifdef}, {IF, cppif}, {ELIF, elif}, {IFNDEF, ifndef}, {ELSE, cppelse}, {ENDIF, endif}, {UNDEF, undef}, {PRAGMA, pragma}, {ERROR, usererr}, {0, NULL} }; int ns; char *p; for (p = input->p; isspace(*p); ++p) ; if (*p != '#') return cppoff; input->p = p+1; disexpand = 1; lexmode = CPPMODE; ns = namespace; namespace = NS_CPPCLAUSES; next(); namespace = NS_IDEN; for (bp = clauses; bp->token && bp->token != yytoken; ++bp) ; if (!bp->token) { errorp("incorrect preprocessor directive '%s'", yytext); goto error; } DBG("CPP %s", yytext); pushctx(); /* create a new context to avoid polish */ (*bp->fun)(); /* the current context, and to get all */ popctx(); /* the symbols freed at the end */ /* * #include changes the content of input->line, so the correctness * of the line must be checked in the own include(), and we have * to skip this tests. For the same reason include() is the only * function which does not prepare the next token */ if (yytoken != '\n' && !cppoff && bp->token != INCLUDE) errorp("trailing characters after preprocessor directive"); error: disexpand = 0; lexmode = CCMODE; namespace = ns; return 1; } void ppragmaln(void) { static char file[FILENAME_MAX]; static unsigned nline; char *s; putchar('\n'); if (strcmp(file, filenam)) { strcpy(file, filenam); s = "#line %u \"%s\"\n"; } else if (nline+1 != lineno) { s = "#line %u\n"; } else { s = ""; } nline = lineno; printf(s, nline, file); } void outcpp(void) { int c; char *s, *t; for (next(); yytoken != EOFTOK; next()) { if (onlyheader) continue; if (yytoken != STRING) { printf("%s ", yytext); continue; } for (s = yytext; c = *s; ++s) { switch (c) { case '\n': t = "\\n"; goto print_str; case '\v': t = "\\v"; goto print_str; case '\b': t = "\\b"; goto print_str; case '\t': t = "\\t"; goto print_str; case '\a': t = "\\a"; print_str: fputs(t, stdout); break; case '\\': putchar('\\'); default: if (!isprint(c)) printf("\\x%x", c); else putchar(c); break; } } putchar(' '); } putchar('\n'); }