scc

parser.c (16076B)

---

 #include <assert.h>
 #include <ctype.h>
 #include <errno.h>
 #include <limits.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "make.h"
 
 #define MAXREPL  30
 #define TABSIZ   64
 #define MAXTOKEN FILENAME_MAX
 #define ITEM     128
 
 typedef struct macro Macro;
 
 enum inputype {
 	FTFILE,
 	FTEXPAN,
 };
 
 enum {
 	STBEGIN,
 	STINTERNAL,
 	STREPLACE,
 	STTO,
 	STEND,
 };
 
 struct input {
 	int siz;
 	int type;
 
 	FILE *fp;
 	struct loc loc;
 
 	int pos;
 	char *buf;
 
 	struct input *prev;
 };
 
 struct macro {
 	char *name;
 	char *value;
 	int where;
 
 	struct macro *next;
 };
 
 static struct input *input;
 static char token[MAXTOKEN];
 static int tok;
 static Macro *htab[TABSIZ];
 
 void
 dumpmacros(void)
 {
 	Macro **pp, *p;
 
 	for (pp = htab; pp < &htab[TABSIZ]; ++pp) {
 		for (p = *pp; p; p = p->next)
 			printf("%s = %s\n", p->name, getmacro(p->name));
 	}
 }
 
 static Macro *
 lookup(char *name)
 {
 	Macro *mp;
 	int h = hash(name) & TABSIZ-1;
 
 	for (mp = htab[h]; mp && strcmp(mp->name, name); mp = mp->next)
 		;
 
 	if (mp)
 		return mp;
 
 	mp = emalloc(sizeof(*mp));
 	mp->name = estrdup(name);
 	mp->value = estrdup("");
 	mp->next = htab[h];
 	mp->where = UNDEF;
 	htab[h] = mp;
 
 	return mp;
 }
 
 static char *
 macroinfo(char *name, int *pwhere, Macro **mpp)
 {
 	char *s, *t;
 	int hide, where;
 	Macro *mp = lookup(name);
 
 	hide = 0;
 	if (!strcmp(name, "SHELL") || !strcmp(name, "MAKEFLAGS"))
 		hide = 1;
 
 	s = mp->value;
 	where = mp->where;
 
 	if (!s && !hide) {
 		where = ENVIRON;
 		s = getenv(name);
 	}
 
 	if (eflag && !hide) {
 		t = getenv(name);
 		if (t) {
 			where = ENVIRON;
 			s = t;
 		}
 	}
 
 	if (pwhere)
 		*pwhere = where;
 	if (mpp)
 		*mpp = mp;
 
 	return s;
 }
 
 char *
 getmacro(char *name)
 {
 	return macroinfo(name, NULL, NULL);
 }
 
 void
 setmacro(char *name, char *val, int where, int export)
 {
 	int owhere, set;
 	char *s;
 	Macro *mp;
 
 	assert(where != ENVIRON);
 
 	s = macroinfo(name, &owhere, &mp);
 
 	/*
 	 *  Default values are defined before anything else, and marked
 	 *  as MAKEFILES because they are injected as parseable text, and
 	 *  MAKEFILE variables are always overriden. ENVIRON macros are
 	 *  generated in macroinfo() and this is why this function should
 	 *  not receive a where == ENVIRON ever.
 	 */
 
 	switch (owhere) {
 	case UNDEF:
 	case MAKEFILE:
 		set = 1;
 		break;
 	case ENVIRON:
 		set = (where == MAKEFLAGS || where == CMDLINE);
 		set |= (where == MAKEFILE && !eflag);
 		break;
 	case MAKEFLAGS:
 		set = (where == CMDLINE || where == MAKEFLAGS);
 		break;
 	case CMDLINE:
 		set = (where == CMDLINE);
 		break;
 	default:
 		abort();
 	}
 
 	if (!set) {
 		debug("hidding override of %s from '%s' to '%s'", name, s, val);
 	} else {
 		debug("override %s from '%s' to '%s'", name, s, val);
 		free(mp->value);
 		mp->value = estrdup(val);
 		mp->where = where;
 
 		if (export && strcmp(name, "SHELL") != 0) {
 			debug("exporting macro %s", name);
 			exportvar(name, val);
 		}
 	}
 }
 
 void
 freeloc(struct loc *loc)
 {
 	free(loc->fname);
 }
 
 static struct loc *
 getloc(void)
 {
 	struct input *ip;
 
 	for (ip = input; ip && ip->type != FTFILE; ip = ip->prev)
 		;
 	if (!ip)
 		return NULL;
 
 	return &ip->loc;
 }
 
 
 void
 error(char *fmt, ...)
 {
 	va_list va;
 	struct loc *loc;
 
 	fprintf(stderr, "make: error: ");
 	if ((loc = getloc()) != NULL)
 		fprintf(stderr, "%s:%d: ", loc->fname, loc->lineno);
 
 	va_start(va, fmt);
 	vfprintf(stderr, fmt, va);
 	va_end(va);
 	putc('\n', stderr);
 
 	exit(EXIT_FAILURE);
 }
 
 void
 warning(char *fmt, ...)
 {
 	va_list va;
 	struct loc *loc;
 
 	fprintf(stderr, "make: warning: ");
 	if ((loc = getloc()) != NULL)
 		fprintf(stderr, "%s:%d: ", loc->fname, loc->lineno);
 
 	va_start(va, fmt);
 	vfprintf(stderr, fmt, va);
 	va_end(va);
 	putc('\n', stderr);
 }
 
 static void
 pop(void)
 {
 	struct input *ip = input->prev;
 
 	if (input->type == FTFILE) {
 		if (input->fp)
 			fclose(input->fp);
 		freeloc(&input->loc);
 	}
 	free(input->buf);
 	free(input);
 
 	input = ip;
 }
 
 static void
 push(int type, ...)
 {
 	int line, len, pos;
 	FILE *fp = NULL;
 	char *buf, *s, *fname = NULL;
 	va_list va;
 	struct input *ip;
 
 	va_start(va, type);
 	switch (type) {
 	case FTFILE:
 		fp = va_arg(va, FILE *);
 		s = va_arg(va, char *);
 		line = va_arg(va, int);
 		fname = estrdup(s);
 		buf = emalloc(BUFSIZ);
 		pos = len = BUFSIZ;
 		break;
 	case FTEXPAN:
 		s = va_arg(va, char *);
 		buf = estrdup(s);
 		line = pos = 0;
 		len = strlen(s);
 		break;
 	}
 	va_end(va);
 
 	ip = emalloc(sizeof(*ip));
 	ip->siz = len;
 	ip->buf = buf;
 	ip->type = type;
 	ip->fp = fp;
 	ip->loc.fname = fname;
 	ip->loc.lineno = line;
 	ip->pos = pos;
 	ip->prev = input;
 
 	input = ip;
 }
 
 static char *
 trim(char *s)
 {
 	size_t len;
 
 	while (isspace(*s))
 		s++;
 
 	for (len = strlen(s); len > 0 && isspace(s[len-1]); --len)
 		s[len-1] = '\0';
 
 	return s;
 }
 
 static void
 include(char *s)
 {
 	int len;
 	FILE *fp;
 	char *fil, *t;
 
 	s = trim(s);
 	fil = expandstring(s, NULL, getloc());
 
 	t = trim(fil);
 	if (strlen(t) != 0) {
 		debug("including '%s'", t);
 		if ((fp = fopen(t, "r")) == NULL)
 			error("opening %s:%s", t, strerror(errno));
 		push(FTFILE, fp, t, 0);
 	}
 
 	free(fil);
 }
 
 static char *
 nextline(void)
 {
 	int c;
 	FILE *fp;
 	char *s, *lim;
 
 	assert(input->type == FTFILE);
 
 repeat:
 	fp = input->fp;
 	if (!fp || feof(fp))
 		return NULL;
 
 	lim = &input->buf[input->siz];
 	for (s = input->buf; s < lim; *s++ = c) {
 		c = getc(fp);
 		if (c == '\n' || c == EOF) {
 			input->loc.lineno++;
 			*s++ = '\n';
 			break;
 		}
 		if (c > UCHAR_MAX || c < 0)
 			error("invalid character '%c' (%d)", c, c);
 	}
 
 
 	if (s == lim)
 		error("too long line");
 	if (ferror(fp))
 		error(strerror(errno));
 	*s = '\0';
 
 	if (!strcmp(input->buf, ""))
 		goto repeat;
 
 	if (strncmp(input->buf, "include", 7) == 0) {
 		input->pos = input->siz;
 		include(input->buf+7);
 		goto repeat;
 	}
 
 	input->pos = 0;
 
 
 	return input->buf;
 }
 
 static int
 empty(struct input *ip)
 {
 	return ip->pos == ip->siz || ip->buf[ip->pos] == '\0';
 }
 
 static int
 moreinput(void)
 {
 	while (input) {
 		if (!empty(input))
 			break;
 
 		switch (input->type) {
 		case FTEXPAN:
 			pop();
 			break;
 		case FTFILE:
 			if (!nextline())
 				pop();
 			break;
 		}
 	}
 
 	return input != NULL;
 }
 
 static int
 nextc(void)
 {
 	if (!moreinput())
 		return EOF;
 
 	return input->buf[input->pos++];
 }
 
 /*
  * This function only can be called after a call to nextc
  * that didn't return EOF. It can return '\0', but as
  * it is used only to check against '$' then it is not
  * a problem.
  */
 static int
 ahead(void)
 {
 	return input->buf[input->pos];
 }
 
 static int
 back(int c)
 {
 	if (c == EOF)
 		return c;
 	assert(input->pos > 0);
 	return input->buf[--input->pos] = c;
 }
 
 static void
 comment(void)
 {
 	int c;
 
 	while ((c = nextc()) != EOF && c != '\n') {
 		if (c == '\\' && nextc() == EOF)
 			break;
 	}
 }
 
 static void
 skipspaces(void)
 {
 	int c;
 
 	for (c = nextc(); c == ' ' || c == '\t'; c = nextc())
 		;
 	back(c);
 }
 
 static int
 validchar(int c)
 {
 	if (c == EOF)
 		return 0;
 	return c == '.' || c == '/' || c == '_' || c == '-' || isalnum(c);
 }
 
 static char *
 expandmacro(char *name)
 {
 	return expandstring(getmacro(name), NULL, getloc());
 }
 
 static void
 replace(char *line, char *repl, char *to)
 {
 	int siz, at, len, replsiz, tosiz, sep, pos;
 	char *oline, *s, *cur, *buf;
 
 	debug("replacing '%s', with '%s' to '%s'", line, repl, to);
 	oline = line;
 	tosiz = strlen(to);
 	replsiz = strlen(repl);
 
 	buf = NULL;
 	for (pos = 0; *line; pos += siz) {
 		cur = NULL;
 		siz = 0;
 
 		for (siz = 0; *line == ' ' || *line == '\t'; ++siz) {
 			cur = erealloc(cur, siz+1);
 			cur[siz] = *line++;
 		}
 
 		len = strcspn(line, " \t");
 		at = len - replsiz;
 		if (at < 0 || memcmp(line + at, repl, replsiz)) {
 			cur = erealloc(cur, siz + len);
 			memcpy(cur + siz, line, len);
 			siz += len;
 		} else {
 			cur = erealloc(cur, siz + at + tosiz);
 			memcpy(cur + siz, line, at);
 			memcpy(cur + siz + at, to, tosiz);
 			siz += at + tosiz;
 		}
 
 		line += len;
 		buf = erealloc(buf, pos + siz);
 		memcpy(buf + pos, cur, siz);
 		free(cur);
 	}
 
 	if (pos > 0) {
 		buf = erealloc(buf, pos + 1);
 		buf[pos] = '\0';
 		debug("\treplace '%s' with '%s'", oline, buf);
 		push(FTEXPAN, buf);
 	}
 
 	free(buf);
 }
 
 static void
 expandsimple(Target *tp)
 {
 	char *s;
 	Target **p;
 	int len, c;
 
 	switch (c = nextc()) {
 	case '@':
 		if (!tp || !tp->target)
 			return;
 		push(FTEXPAN, tp->target);
 		break;
 	case '<':
 		if (!tp || !tp->req)
 			return;
 		push(FTEXPAN, tp->req);
 		break;
 	case '*':
 		if (!tp || !tp->target)
 			return;
 		s = strrchr(tp->target, '.');
 		if (!s) {
 			push(FTEXPAN, tp->target);
 			return;
 		}
 
 		len = s - tp->target;
 		s = emalloc(len+1);
 		memcpy(s, tp->target, len);
 		s[len] = '\0';
 		push(FTEXPAN, s);
 		free(s);
 		break;
 	case '?':
 		if (!tp)
 			return;
 
 		if (tp->req && stamp(tp->req) > tp->stamp) {
 			push(FTEXPAN, " ");
 			push(FTEXPAN, tp->req);
 		}
 
 		for (p = tp->deps; p && *p; ++p) {
 			if (stamp((*p)->name) > tp->stamp) {
 				push(FTEXPAN, " ");
 				push(FTEXPAN, (*p)->name);
 			}
 		}
 		break;
 	default:
 		token[0] = c;
 		token[1] = '\0';
 		s = expandmacro(token);
 		push(FTEXPAN, s);
 		free(s);
 		break;
 	}
 }
 
 static int
 internal(int ch)
 {
 	switch (ch) {
 	case '@':
 	case '?':
 	case '*':
 	case '<':
 		return 1;
 	default:
 		return 0;
 	}
 }
 
 static void
 expansion(Target *tp)
 {
 	int delim, c, repli, toi, namei, st;
 	char name[MAXTOKEN], repl[MAXREPL], to[MAXREPL];
 	char *s, *erepl;
 
 	c = nextc();
 	if (c == '(')
 		delim = ')';
 	else if (c == '{')
 		delim = '}';
 	else
 		delim = 0;
 
 	if (!delim) {
 		back(c);
 		expandsimple(tp);
 		return;
 	}
 
 	s = NULL;
 	namei = repli = toi = 0;
 	st = STBEGIN;
 
 	while (st != STEND && (c = nextc()) != EOF) {
 		switch (st) {
 		case STBEGIN:
 			if (c == ':') {
 				st = STREPLACE;
 				name[namei] = '\0';
 				s = expandmacro(name);
 				break;
 			}
 			if (c == delim) {
 				name[namei] = '\0';
 				s = expandmacro(name);
 				goto no_replace;
 			}
 			if (namei == MAXTOKEN-1)
 				error("expansion text too long");
 
 			if (namei == 0 && internal(c)) {
 				name[namei++] = '$';
 				name[namei++] = c;
 				name[namei] = '\0';
 				st = STINTERNAL;
 				s = expandstring(name, tp, getloc());
 				break;
 			}
 
 			if (!validchar(c))
 				error("invalid macro name in expansion");
 			name[namei++] = c;
 			break;
 		case STINTERNAL:
 			if (c == delim)
 				goto no_replace;
 			if (c != ':')
 				error("invalid internal macro in expansion");
 			st = STREPLACE;
 			break;
 		case STREPLACE:
 			if (c == '=') {
 				st = STTO;
 				break;
 			}
 			if (c == delim)
 				error("invalid replacement pattern in expansion");
 			if (repli == MAXREPL-1)
 				error("macro replacement too big");
 			repl[repli++] = c;
 			break;
 		case STTO:
 			if (c == delim) {
 				st = STEND;
 				break;
 			}
 
 			if (toi == MAXREPL-1)
 				error("macro substiturion too big");
 			to[toi++] = c;
 			break;
 		}
 	}
 
 	if (c == EOF)
 		error("found eof while parsing expansion");
 
 	repl[repli] = '\0';
 	to[toi] = '\0';
 
 	erepl = expandstring(repl, tp, getloc());
 	replace(s, erepl, to);
 
 	free(erepl);
 	free(s);
 	return;
 
 no_replace:
 	push(FTEXPAN, s);
 	free(s);
 }
 
 /*
  * Horrible hack to do string expansion.
  * We cannot use normal push and nextc because that
  * would consume characters of the current file too.
  * For that reason it cleans the input and it recovers
  * it later.
  */
 char *
 expandstring(char *line, Target *tp, struct loc *loc)
 {
 	int c, n;
 	char *s;
 	struct input *ip = input;
 
 	input = NULL;
 	push(FTFILE, NULL, loc->fname, loc->lineno);
 	push(FTEXPAN, line);
 
 	n = 0;
 	s = NULL;
 	while ((c = nextc()) != EOF) {
 		if (c != '$') {
 			s = erealloc(s, ++n);
 			s[n-1] = c;
 			continue;
 		}
 
 		if ((c = nextc()) == '$') {
 			s = erealloc(s, n += 2);
 			s[n-2] = '$';
 			s[n-1] = '$';
 		} else {
 			back(c);
 			expansion(tp);
 		}
 	}
 
 	s = erealloc(s, n+1);
 	s[n] = '\0';
 	input = ip;
 
 	return s;
 }
 
 static int
 item(void)
 {
 	int c;
 	char *s;
 	char buf[MAXTOKEN];
 
 	for (s = buf; s < &buf[MAXTOKEN] - 1; ) {
 		c = nextc();
 		if (c == '$' && ahead() != '$')
 			expansion(NULL);
 		else if (validchar(c))
 			*s++ = c;
 		else
 			break;
 	}
 	back(c);
 
 	if (s >= &buf[MAXTOKEN] - 1)
 		error("token too long");
 	if (s == buf)
 		error("invalid empty token");
 	*s++ = '\0';
 	memcpy(token, buf, s - buf);
 
 	return ITEM;
 }
 
 static int
 next(void)
 {
 	int c;
 
 repeat:
 	/*
 	 * It is better to avoid skipspaces() here, because
 	 * it can generate the need for 2 calls to back(),
 	 * and we need the character anyway.
 	 */
 	c = nextc();
 	if (c == ' ' || c == '\t')
 		goto repeat;
 
 	if (c == '\\') {
 		if ((c = nextc()) == '\n')
 			goto repeat;
 		back(c);
 		c = '\\';
 	}
 
 	switch (c) {
 	case EOF:
 		strcpy(token, "<EOF>");
 		tok = EOF;
 		break;
 	case '$':
 		if ((c = nextc()) == '$')
 			goto single;
 		back(c);
 		expansion(NULL);
 		goto repeat;
 	case '#':
 		comment();
 		c = '\n';
 	case ';':
 	case ':':
 	case '=':
 	case '\n':
 	single:
 		token[0] = c;
 		token[1] = '\0';
 		tok = c;
 		break;
 	default:
 		if (!validchar(c))
 			error("unexpected character '%c'", c);
 		back(c);
 		tok = item();
 		break;
 	}
 
 	return tok;
 }
 
 static char *
 readmacrodef(void)
 {
 	int n, c;
 	char *line;
 
 	n = 0;
 	line = NULL;
 	while ((c = nextc()) != EOF) {
 		line = erealloc(line, n+1);
 		if (c == '\n')
 			break;
 		if (c == '#') {
 			comment();
 			break;
 		}
 		if (c == '\\') {
 			if ((c = nextc()) != '\n') {
 				back(c);
 				c = '\\';
 			} else {
 				skipspaces();
 				c = ' ';
 			}
 		}
 
 		line[n++] = c;
 	}
 	if (c == EOF)
 		error("EOF while looking for end of line");
 	line[n] = '\0';
 
 	return line;
 }
 
 static struct action
 readcmd(void)
 {
 	int n, c;
 	struct loc *loc;
 	struct action act;
 
 	skipspaces();
 
 	loc = getloc();
 	act.loc.fname = estrdup(loc->fname);
 	act.loc.lineno = loc->lineno;
 
 	n = 0;
 	act.line = NULL;
 	while ((c = nextc()) != EOF) {
 		act.line = erealloc(act.line, n+1);
 		if (c == '\n')
 			break;
 		if (c == '\\') {
 			if ((c = nextc()) == '\n') {
 				if ((c = nextc()) != '\t')
 					back(c);
 				continue;
 			}
 			back(c);
 			c = '\\';
 		}
 		act.line[n++] = c;
 	}
 	if (c == EOF)
 		error("EOF while looking for end of command");
 	act.line[n] = '\0';
 
 	return act;
 }
 
 static void
 rule(char *targets[], int ntargets)
 {
 	int c, i, j, ndeps, nactions;
 	struct action *acts;
 	char **deps = NULL;
 
 	if (ntargets == 0)
 		error("missing target");
 
 	for (ndeps = 0; next() == ITEM; ++ndeps) {
 		deps = erealloc(deps, (ndeps+1) * sizeof(char *));
 		deps[ndeps] = estrdup(token);
 	}
 
 	if (tok != '\n' && tok != ';')
 		error("garbage at the end of the line");
 
 	nactions = 0;
 	acts = NULL;
 	if (tok == ';') {
 		nactions++;
 		acts = erealloc(acts, nactions * sizeof(*acts));
 		acts[nactions-1] = readcmd();
 	}
 
 	for (;;) {
 		if ((c = nextc()) == '#') {
 			comment();
 			continue;
 		}
 		if (c != '\t')
 			break;
 		nactions++;
 		acts = erealloc(acts, nactions * sizeof(*acts));
 		acts[nactions-1] = readcmd();
 	}
 	back(c);
 
 	for (i = 0; i < ntargets; i++) {
 		addtarget(targets[i], ndeps);
 		for (j = 0; j < ndeps; j++)
 			adddep(targets[i], deps[j]);
 		if (nactions > 0)
 			addrule(targets[i], acts, nactions);
 	}
 
 	for (i = 0; i < ndeps; i++)
 		free(deps[i]);
 	free(deps);
 
 	for (i = 0; i < nactions; i++) {
 		free(acts[i].line);
 		freeloc(&acts[i].loc);
 	}
 	free(acts);
 }
 
 static void
 assign(char *macros[], int n)
 {
 	char *defs;
 
 	if (n != 1)
 		error("invalid macro definition");
 
 	skipspaces();
 	defs = readmacrodef();
 	setmacro(*macros, defs, MAKEFILE, NOEXPORT);
 	free(defs);
 }
 
 void
 parseinput(void)
 {
 	int i, n;
 	char **targets;
 
 	while (moreinput()) {
 		n = 0;
 		targets = NULL;
 
 		next();
 		if (tok == '\n')
 			continue;
 
 		while (tok == ITEM) {
 			n++;
 			targets = erealloc(targets, n * sizeof(char *));
 			targets[n-1] = estrdup(token);
 			next();
 		}
 
 		switch (tok) {
 		case ':':
 			rule(targets, n);
 			break;
 		case '=':
 			assign(targets, n);
 			break;
 		default:
 			error("unexpected token '%s'(%d)", token, tok);
 		}
 
 		for (i = 0; i < n; i++)
 			free(targets[i]);
 		free(targets);
 	}
 }
 
 int
 parse(char *fname)
 {
 	FILE *fp;
 
 	if (!fname) {
 		fp = stdin;
 		fname = "<stdin>";
 	} else if ((fp = fopen(fname, "r")) == NULL) {
 		return 0;
 	}
 
 	debug("parsing %s", fname);
 	push(FTFILE, fp, fname, 0);
 	parseinput();
 
 	return 1;
 }
 
 void
 inject(char *s)
 {
 	push(FTFILE, NULL, "<internal>", 0);
 	push(FTEXPAN, s);
 	parseinput();
 }