lcc.c

c语言编译器

/*
 * lcc [ option ]... [ file | -llib ]...
 * front end for the ANSI C compiler
 */
static char rcsid[] = "$Id: lcc.c,v 4.33 2001/06/28 22:19:58 drh Exp $";

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <signal.h>

#ifndef TEMPDIR
#define TEMPDIR "/tmp"
#endif

typedef struct list *List;
struct list {		/* circular list nodes: */
	char *str;		/* option or file name */
	List link;		/* next list element */
};

static void *alloc(int);
static List append(char *,List);
extern char *basepath(char *);
static int callsys(char *[]);
extern char *concat(char *, char *);
static int compile(char *, char *);
static void compose(char *[], List, List, List);
static void error(char *, char *);
static char *exists(char *);
static char *first(char *);
static int filename(char *, char *);
static List find(char *, List);
static void help(void);
static void initinputs(void);
static void interrupt(int);
static void opt(char *);
static List path2list(const char *);
extern int main(int, char *[]);
extern char *replace(const char *, int, int);
static void rm(List);
extern char *strsave(const char *);
extern char *stringf(const char *, ...);
extern int suffix(char *, char *[], int);
extern char *tempname(char *);

extern int access(char *, int);
extern int getpid(void);

extern char *cpp[], *include[], *com[], *as[],*ld[], inputs[], *suffixes[];
extern int option(char *);

static int errcnt;		/* number of errors */
static int Eflag;		/* -E specified */
static int Sflag;		/* -S specified */
static int cflag;		/* -c specified */
static int verbose;		/* incremented for each -v */
static List llist[2];		/* loader files, flags */
static List alist;		/* assembler flags */
static List clist;		/* compiler flags */
static List plist;		/* preprocessor flags */
static List ilist;		/* list of additional includes from LCCINPUTS */
static List rmlist;		/* list of files to remove */
static char *outfile;		/* ld output file or -[cS] object file */
static int ac;			/* argument count */
static char **av;		/* argument vector */
char *tempdir = TEMPDIR;	/* directory for temporary files */
static char *progname;
static List lccinputs;		/* list of input directories */

main(int argc, char *argv[]) {
	int i, j, nf;
	
	progname = argv[0];
	ac = argc + 50;
	av = alloc(ac*sizeof(char *));
	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
		signal(SIGINT, interrupt);
	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
		signal(SIGTERM, interrupt);
#ifdef SIGHUP
	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
		signal(SIGHUP, interrupt);
#endif
	if (getenv("TMP"))
		tempdir = getenv("TMP");
	else if (getenv("TEMP"))
		tempdir = getenv("TEMP");
	else if (getenv("TMPDIR"))
		tempdir = getenv("TMPDIR");
	assert(tempdir);
	i = strlen(tempdir);
	for (; i > 0 && tempdir[i-1] == '/' || tempdir[i-1] == '\\'; i--)
		tempdir[i-1] = '\0';
	if (argc <= 1) {
		help();
		exit(0);
	}
	plist = append("-D__LCC__", 0);
	initinputs();
	if (getenv("LCCDIR"))
		option(stringf("-lccdir=%s", getenv("LCCDIR")));
	for (nf = 0, i = j = 1; i < argc; i++) {
		if (strcmp(argv[i], "-o") == 0) {
			if (++i < argc) {
				if (suffix(argv[i], suffixes, 2) >= 0) {
					error("-o would overwrite %s", argv[i]);
					exit(8);
				}
				outfile = argv[i];
				continue;
			} else {
				error("unrecognized option `%s'", argv[i-1]);
				exit(8);
			}
		} else if (strcmp(argv[i], "-target") == 0) {
			if (argv[i+1] && *argv[i+1] != '-')
				i++;
			continue;
		} else if (*argv[i] == '-' && argv[i][1] != 'l') {
			opt(argv[i]);
			continue;
		} else if (*argv[i] != '-' && suffix(argv[i], suffixes, 3) >= 0)
			nf++;
		argv[j++] = argv[i];
	}
	if ((cflag || Sflag) && outfile && nf != 1) {
		fprintf(stderr, "%s: -o %s ignored\n", progname, outfile);
		outfile = 0;
	}
	argv[j] = 0;
	for (i = 0; include[i]; i++)
		plist = append(include[i], plist);
	if (ilist) {
		List b = ilist;
		do {
			b = b->link;
			plist = append(b->str, plist);
		} while (b != ilist);
	}
	ilist = 0;
	for (i = 1; argv[i]; i++)
		if (strcmp(argv[i], "-l") == 0 && argv[i+1] && *argv[i+1] != '-') {	/* -l file */
			llist[1] = append(argv[i++], llist[1]);
			llist[1] = append(argv[i],   llist[1]);
		} else if (*argv[i] == '-')
			opt(argv[i]);
		else {
			char *name = exists(argv[i]);
			if (name) {
				if (strcmp(name, argv[i]) != 0
				|| nf > 1 && suffix(name, suffixes, 3) >= 0)
					fprintf(stderr, "%s:\n", name);
				filename(name, 0);
			} else
				error("can't find `%s'", argv[i]);
		}
	if (errcnt == 0 && !Eflag && !Sflag && !cflag && llist[1]) {
		compose(ld, llist[0], llist[1],
			append(outfile ? outfile : concat("a", first(suffixes[4])), 0));
		if (callsys(av))
			errcnt++;
	}
	rm(rmlist);	
	return errcnt ? EXIT_FAILURE : EXIT_SUCCESS;
}

/* alloc - allocate n bytes or die */
static void *alloc(int n) {
	static char *avail, *limit;
	
	n = (n + sizeof(char *) - 1)&~(sizeof(char *) - 1);
	if (n >= limit - avail) {
		avail = malloc(n + 4*1024);
		assert(avail);
		limit = avail + n + 4*1024;
	}
	avail += n;
	return avail - n;
}

/* append - append a node with string str onto list, return new list */	
static List append(char *str, List list) {
	List p = alloc(sizeof *p);

	p->str = str;
	if (list) {
		p->link = list->link;
		list->link = p;
	} else
		p->link = p;
	return p;
}

/* basepath - return base name for name, e.g. /usr/drh/foo.c => foo */
char *basepath(char *name) {
	char *s, *b, *t = 0;

	for (b = s = name; *s; s++)
		if (*s == '/' || *s == '\\') {
			b = s + 1;
			t = 0;
		} else if (*s == '.')
			t = s;
	s = strsave(b);
	if (t)
		s[t-b] = 0;
	return s;
}

#ifdef WIN32
#include <process.h>
#else
#define _P_WAIT 0
extern int fork(void);
extern int wait(int *);
extern void execv(const char *, char *[]);

static int _spawnvp(int mode, const char *cmdname, const char *const argv[]) {
	int pid, n, status;

	switch (pid = fork()) {
	case -1:
		fprintf(stderr, "%s: no more processes\n", progname);
		return 100;
	case 0:
		execv(cmdname, (char **)argv);
		fprintf(stderr, "%s: ", progname);
		perror(cmdname);
		fflush(stdout);
		exit(100);
	}
	while ((n = wait(&status)) != pid && n != -1)
		;
	if (n == -1)
		status = -1;
	if (status&0377) {
		fprintf(stderr, "%s: fatal error in %s\n", progname, cmdname);
		status |= 0400;
	}
	return (status>>8)&0377;
}
#endif

/* callsys - execute the command described by av[0...], return status */
static int callsys(char **av) {
	int i, status = 0;
	static char **argv;
	static int argc;

	for (i = 0; av[i] != NULL; i++)
		;
	if (i + 1 > argc) {
		argc = i + 1;
		if (argv == NULL)
			argv = malloc(argc*sizeof *argv);
		else
			argv = realloc(argv, argc*sizeof *argv);
		assert(argv);
	}
	for (i = 0; status == 0 && av[i] != NULL; ) {
		int j = 0;
		char *s;
		for ( ; av[i] != NULL && (s = strchr(av[i], '\n')) == NULL; i++)
			argv[j++] = av[i];
		if (s != NULL) {
			if (s > av[i])
				argv[j++] = stringf("%.*s", s - av[i], av[i]);
			if (s[1] != '\0')
				av[i] = s + 1;
			else
				i++;
		}
		argv[j] = NULL;
		if (verbose > 0) {
			int k;
			fprintf(stderr, "%s", argv[0]);
			for (k = 1; argv[k] != NULL; k++)
				fprintf(stderr, " %s", argv[k]);
			fprintf(stderr, "\n");
		}
		if (verbose < 2)
			status = _spawnvp(_P_WAIT, argv[0], (const char * const *)argv);
		if (status == -1) {
			fprintf(stderr, "%s: ", progname);
			perror(argv[0]);
		}
	}
	return status;
}

/* concat - return concatenation of strings s1 and s2 */
char *concat(char *s1, char *s2) {
	int n = strlen(s1);
	char *s = alloc(n + strlen(s2) + 1);

	strcpy(s, s1);
	strcpy(s + n, s2);
	return s;
}

/* compile - compile src into dst, return status */
static int compile(char *src, char *dst) {
	compose(com, clist, append(src, 0), append(dst, 0));
	return callsys(av);
}

/* compose - compose cmd into av substituting a, b, c for $1, $2, $3, resp. */
static void compose(char *cmd[], List a, List b, List c) {
	int i, j;
	List lists[3];

	lists[0] = a;
	lists[1] = b;
	lists[2] = c;
	for (i = j = 0; cmd[i]; i++) {
		char *s = strchr(cmd[i], '$');
		if (s && isdigit(s[1])) {
			int k = s[1] - '0';
			assert(k >=1 && k <= 3);
			if (b = lists[k-1]) {
				b = b->link;
				av[j] = alloc(strlen(cmd[i]) + strlen(b->str) - 1);
				strncpy(av[j], cmd[i], s - cmd[i]);
				av[j][s-cmd[i]] = '\0';
				strcat(av[j], b->str);
				strcat(av[j++], s + 2);
				while (b != lists[k-1]) {
					b = b->link;
					assert(j < ac);
					av[j++] = b->str;
				};
			}
		} else if (*cmd[i]) {
			assert(j < ac);
			av[j++] = cmd[i];
		}
	}
	av[j] = NULL;
}

/* error - issue error msg according to fmt, bump error count */
static void error(char *fmt, char *msg) {
	fprintf(stderr, "%s: ", progname);
	fprintf(stderr, fmt, msg);
	fprintf(stderr, "\n");
	errcnt++;
}

/* exists - if `name' readable return its path name or return null */
static char *exists(char *name) {
	List b;

	if ( (name[0] == '/' || name[0] == '\\' || name[2] == ':')
	&& access(name, 4) == 0)
		return name;
	if (!(name[0] == '/' || name[0] == '\\' || name[2] == ':')
	&& (b = lccinputs))		
		do {
			b = b->link;
			if (b->str[0]) {
				char buf[1024];
				sprintf(buf, "%s/%s", b->str, name);
				if (access(buf, 4) == 0)
					return strsave(buf);
			} else if (access(name, 4) == 0)
				return name;
		} while (b != lccinputs);
	if (verbose > 1)
		return name;
	return 0;
}

/* first - return first component in semicolon separated list */
static char *first(char *list) {
	char *s = strchr(list, ';');

	if (s) {
		char buf[1024];
		strncpy(buf, list, s-list);
		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 = basepath(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;