lcc

c语言编译器

		buf[s-list] = '\0';
		return strsave(buf);
	} else
		return list;
}

/* filename - process file name argument `name', return status */
static int filename(char *name, char *base) {
	int status = 0;
	static char *stemp, *itemp;

	if (base == 0)
		base = basename(name);
	switch (suffix(name, suffixes, 4)) {
	case 0:	/* C source files */
		compose(cpp, plist, append(name, 0), 0);
		if (Eflag) {
			status = callsys(av);
			break;
		}
		if (itemp == NULL)
			itemp = tempname(first(suffixes[1]));
		compose(cpp, plist, append(name, 0), append(itemp, 0));
		status = callsys(av);
		if (status == 0)
			return filename(itemp, base);
		break;
	case 1:	/* preprocessed source files */
		if (Eflag)
			break;
		if (Sflag)
			status = compile(name, outfile ? outfile : concat(base, first(suffixes[2])));
		else if ((status = compile(name, stemp?stemp:(stemp=tempname(first(suffixes[2]))))) == 0)
			return filename(stemp, base);
		break;
	case 2:	/* assembly language files */
		if (Eflag)
			break;
		if (!Sflag) {
			char *ofile;
			if (cflag && outfile)
				ofile = outfile;
			else if (cflag)
				ofile = concat(base, first(suffixes[3]));
			else
				ofile = tempname(first(suffixes[3]));
			compose(as, alist, append(name, 0), append(ofile, 0));
			status = callsys(av);
			if (!find(ofile, llist[1]))
				llist[1] = append(ofile, llist[1]);
		}
		break;
	case 3:	/* object files */
		if (!find(name, llist[1]))
			llist[1] = append(name, llist[1]);
		break;
	default:
		if (Eflag) {
			compose(cpp, plist, append(name, 0), 0);
			status = callsys(av);
		}
		llist[1] = append(name, llist[1]);
		break;
	}
	if (status)
		errcnt++;
	return status;
}

/* find - find 1st occurrence of str in list, return list node or 0 */
static List find(char *str, List list) {
	List b;

	if (b = list)
		do {
			if (strcmp(str, b->str) == 0)
				return b;
		} while ((b = b->link) != list);
	return 0;
}

/* help - print help message */
static void help(void) {
	static char *msgs[] = {
"", " [ option | file ]...\n",
"	except for -l, options are processed left-to-right before files\n",
"	unrecognized options are taken to be linker options\n",
"-A	warn about nonANSI usage; 2nd -A warns more\n",
"-b	emit expression-level profiling code; see bprint(1)\n",
#ifdef riscos
"-Bunix	link with UnixLib rather than CLib\n",
#endif
"-Bdir/	use the compiler named `dir/rcc'\n",
"-c	compile only\n",
"-dn	set switch statement density to `n'\n",
"-Dname -Dname=def	define the preprocessor symbol `name'\n",
"-E	run only the preprocessor on the named C programs and unsuffixed files\n",
"-g	produce symbol table information for debuggers\n",
"-help	print this message\n",
"-Idir	add `dir' to the beginning of the list of #include directories\n",
"-lx	search library `x'\n",
"-N	do not search the standard directories for #include files\n",
"-n	emit code to check for dereferencing zero pointers\n",
"-O	is ignored\n",
"-o file	leave the output in `file'\n",
"-P	print ANSI-style declarations for globals\n",
"-p -pg	emit profiling code; see prof(1) and gprof(1)\n",
"-S	compile to assembly language\n",
"-t -tname	emit function tracing calls to printf or to `name'\n",
"-target name	is ignored\n",
"-tempdir=dir	place temporary files in `dir/'\n",
"-Uname	undefine the preprocessor symbol `name'\n",
"-v	show commands as they are executed; 2nd -v suppresses execution\n",
"-w	suppress warnings\n",
"-W[pfal]arg	pass `arg' to the preprocessor, compiler, assembler, or linker\n",
	0 };
	int i;

	msgs[0] = progname;
	for (i = 0; msgs[i]; i++)
		fprintf(stderr, "%s", msgs[i]);
}

/* initinputs - if LCCINPUTS is defined, use it to initialize various lists */
static void initinputs(void) {
	char *s = getenv("LCCINPUTS"), sep = ':';

	if (s == 0 && (s = inputs)[0] == 0)
		s = ".";
	else if (strchr(s, ';'))
		sep = ';';
	while (*s) {
		char *p, buf[256];
		if (p = strchr(s, sep)) {
			assert(p - s < sizeof buf);
			strncpy(buf, s, p - s);
			buf[p-s] = '\0';
		} else {
			assert(strlen(s) < sizeof buf);
			strcpy(buf, s);
		}
		if (strcmp(buf, ".") == 0)
			buf[0] = '\0';
		if (!find(buf, lccinputs)) {
			lccinputs = append(strsave(buf), lccinputs);
			if (buf[0]) {
				ilist = append(concat("-I", buf), ilist);
				if (strstr(com[1], "win32") == NULL)
					llist[0] = append(concat("-L", buf), llist[0]);
			}
		}
		if (p == 0)
			break;
		s = p + 1;
	}
}

/* interrupt - catch interrupt signals */
static void interrupt(int n) {
	rm(rmlist);
	exit(n = 100);
}

/* opt - process option in arg */
static void opt(char *arg) {
	switch (arg[1]) {	/* multi-character options */
	case 'W':	/* -Wxarg */
		if (arg[2] && arg[3])
			switch (arg[2]) {
			case 'o':
				if (option(&arg[3]))
					return;
				break;
			case 'p':
				plist = append(&arg[3], plist);
				return;
			case 'f':
				if (strcmp(&arg[3], "-C") || option("-b")) {
					clist = append(&arg[3], clist);
					return;
				}
				break; /* and fall thru */
			case 'a':
				alist = append(&arg[3], alist);
				return;
			case 'l':
				llist[0] = append(&arg[3], llist[0]);
				return;
			}
		fprintf(stderr, "%s: %s ignored\n", progname, arg);
		return;
	case 'd':	/* -dn */
		arg[1] = 's';
		clist = append(arg, clist);
		return;
	case 't':	/* -t -tname -tempdir=dir */
		if (strncmp(arg, "-tempdir=", 9) == 0)
			tempdir = arg + 9;
		else
			clist = append(arg, clist);
		return;
	case 'p':	/* -p -pg */
		if (option(arg))
			clist = append(arg, clist);
		else
			fprintf(stderr, "%s: %s ignored\n", progname, arg);
		return;
	case 'D':	/* -Dname -Dname=def */
	case 'U':	/* -Uname */
	case 'I':	/* -Idir */
		plist = append(arg, plist);
		return;
	case 'B':	/* -Bdir -Bstatic -Bdynamic */
#ifdef riscos
		if (strcmp(arg, "-Bunix") == 0) {
			include[0] = "-IUnix:";
			ld[3] = "";
			ld[6] = "-LGCC:";
			ld[7] = "-lgcc";
			ld[8] = "-LUnix:";
			ld[9] = "-lUnixLib";
		} else
#endif
		{
		static char *path;
		if (path)
			error("-B overwrites earlier option", 0);
		path = arg + 2;
		if (strstr(com[1], "win32") != NULL)
			com[0] = concat(replace(path, '/', '\\'), concat("rcc", first(suffixes[4])));
		else
			com[0] = concat(path, "rcc");
		if (path[0] == 0)
			error("missing directory in -B option", 0);
		}
		return;
	case 'h':
		if (strcmp(arg, "-help") == 0) {
			static int printed = 0;
			if (!printed)
				help();
			printed = 1;
			return;
		}
	}
	if (arg[2] == 0)
		switch (arg[1]) {	/* single-character options */
		case 'S':
			Sflag++;
			return;
		case 'O':
			fprintf(stderr, "%s: %s ignored\n", progname, arg);
			return;
		case 'A': case 'n': case 'w': case 'P':
			clist = append(arg, clist);
			return;
		case 'g': case 'b':
			if (option(arg))
				clist = append(arg[1] == 'g' ? "-g2" : arg, clist);
			else
				fprintf(stderr, "%s: %s ignored\n", progname, arg);
			return;
		case 'G':
			if (option(arg)) {
				clist = append("-g3", clist);
				llist[0] = append("-N", llist[0]);
			} else
				fprintf(stderr, "%s: %s ignored\n", progname, arg);
			return;
		case 'E':
			Eflag++;
			return;
		case 'c':
			cflag++;
			return;
		case 'N':
			if (strcmp(basename(cpp[0]), "gcc-cpp") == 0)
				plist = append("-nostdinc", plist);
			include[0] = 0;
			ilist = 0;
			return;
		case 'v':
			if (verbose++ == 0) {
				if (strcmp(basename(cpp[0]), "gcc-cpp") == 0)
					plist = append(arg, plist);
				clist = append(arg, clist);
				fprintf(stderr, "%s %s\n", progname, rcsid);
			}
			return;
		}
	if (cflag || Sflag || Eflag)
		fprintf(stderr, "%s: %s ignored\n", progname, arg);
	else
		llist[1] = append(arg, llist[1]);
}

/* replace - copy str, then replace occurrences of from with to, return the copy */
char *replace(const char *str, int from, int to) {
	char *s = strsave(str), *p = s;

	for ( ; (p = strchr(p, from)) != NULL; p++)
		*p = to;
	return s;
}

/* rm - remove files in list */
static void rm(List list) {
	if (list) {
		List b = list;
		if (verbose)
			fprintf(stderr, "rm");
		do {
			if (verbose)
				fprintf(stderr, " %s", b->str);
			if (verbose < 2)
				remove(b->str);
		} while ((b = b->link) != list);
		if (verbose)
			fprintf(stderr, "\n");
	}
}

/* strsave - return a saved copy of string str */
char *strsave(const char *str) {
	return strcpy(alloc(strlen(str)+1), str);
}

/* stringf - format and return a string */
char *stringf(const char *fmt, ...) {
	char buf[1024];
	va_list ap;
	int n;

	va_start(ap, fmt);
	n = vsprintf(buf, fmt, ap);
	va_end(ap);
	return strsave(buf);
}

/* suffix - if one of tails[0..n-1] holds a proper suffix of name, return its index */
int suffix(char *name, char *tails[], int n) {
	int i, len = strlen(name);

	for (i = 0; i < n; i++) {
		char *s = tails[i], *t;
		for ( ; t = strchr(s, ';'); s = t + 1) {
			int m = t - s;
			if (len > m && strncmp(&name[len-m], s, m) == 0)
				return i;
		}
		if (*s) {
			int m = strlen(s);
			if (len > m && strncmp(&name[len-m], s, m) == 0)
				return i;
		}
	}
	return -1;
}

/* tempname - generate a temporary file name in tempdir with given suffix */
char *tempname(char *suffix) {
	static int n;
	char *name = stringf("%s/lcc%d%d%s", tempdir, getpid(), n++, suffix);

	if (strstr(com[1], "win32") != NULL)
		name = replace(name, '/', '\\');
	rmlist = append(name, rmlist);
	return name;
}