view directive.c @ 175:ffdb0b73856f

Suppress blank lines later. Fixes the rest of the bizarre spacing behavior described in changeset 82cc6fa54b01. Expand t39 to cover more cases, too.
author David A. Holland
date Fri, 12 Jun 2015 02:38:04 -0400
parents 6ff17ab68b16
children a2f047301c15
line wrap: on
line source

/*-
 * Copyright (c) 2010, 2013 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by David A. Holland.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <assert.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <errno.h>

#include "utils.h"
#include "mode.h"
#include "place.h"
#include "files.h"
#include "directive.h"
#include "macro.h"
#include "eval.h"
#include "output.h"

struct ifstate {
	struct ifstate *prev;
	struct place startplace;
	bool curtrue;
	bool evertrue;
	bool seenelse;
};

static struct ifstate *ifstate;

////////////////////////////////////////////////////////////
// common parsing bits

static
void
uncomment(char *buf)
{
	char *s, *t, *u = NULL;
	bool incomment = false;
	bool inesc = false;
	bool inquote = false;
	char quote = '\0';

	for (s = t = buf; *s; s++) {
		if (incomment) {
			if (s[0] == '*' && s[1] == '/') {
				s++;
				incomment = false;
			}
		} else {
			if (!inquote && s[0] == '/' && s[1] == '*') {
				incomment = true;
			} else {
				if (inesc) {
					inesc = false;
				} else if (s[0] == '\\') {
					inesc = true;
				} else if (!inquote &&
					   (s[0] == '"' || s[0] == '\'')) {
					inquote = true;
					quote = s[0];
				} else if (inquote && s[0] == quote) {
					inquote = false;
				}

				if (t != s) {
					*t = *s;
				}
				if (!strchr(ws, *t)) {
					u = t;
				}
				t++;
			}
		}
	}
	if (u) {
		/* end string after last non-whitespace char */
		u[1] = '\0';
	} else {
		*t = '\0';
	}
}

static
void
oneword(const char *what, struct place *p2, char *line)
{
	size_t pos;

	pos = strcspn(line, ws);
	if (line[pos] != '\0') {
		p2->column += pos;
		complain(p2, "Garbage after %s argument", what);
		complain_fail();
		line[pos] = '\0';
	}
}

////////////////////////////////////////////////////////////
// if handling

static
struct ifstate *
ifstate_create(struct ifstate *prev, struct place *p, bool startstate)
{
	struct ifstate *is;

	is = domalloc(sizeof(*is));
	is->prev = prev;
	if (p != NULL) {
		is->startplace = *p;
	} else {
		place_setbuiltin(&is->startplace, 1);
	}
	is->curtrue = startstate;
	is->evertrue = is->curtrue;
	is->seenelse = false;
	return is;
}

static
void
ifstate_destroy(struct ifstate *is)
{
	dofree(is, sizeof(*is));
}

static
void
ifstate_push(struct place *p, bool startstate)
{
	struct ifstate *newstate;

	newstate = ifstate_create(ifstate, p, startstate);
	if (!ifstate->curtrue) {
		newstate->curtrue = false;
		newstate->evertrue = true;
	}
	ifstate = newstate;
}

static
void
ifstate_pop(void)
{
	struct ifstate *is;

	is = ifstate;
	ifstate = ifstate->prev;
	ifstate_destroy(is);
}

static
void
d_if(struct lineplace *lp, struct place *p2, char *line)
{
	char *expr;
	bool val;
	struct place p3 = *p2;
	size_t oldlen;

	expr = macroexpand(p2, line, strlen(line), true);

	oldlen = strlen(expr);
	uncomment(expr);
	/* trim to fit, so the malloc debugging won't complain */
	expr = dorealloc(expr, oldlen + 1, strlen(expr) + 1);

	if (ifstate->curtrue) {
		val = eval(&p3, expr);
	} else {
		val = 0;
	}
	ifstate_push(&lp->current, val);
	dostrfree(expr);
}

static
void
d_ifdef(struct lineplace *lp, struct place *p2, char *line)
{
	uncomment(line);
	oneword("#ifdef", p2, line);
	ifstate_push(&lp->current, macro_isdefined(line));
}

static
void
d_ifndef(struct lineplace *lp, struct place *p2, char *line)
{
	uncomment(line);
	oneword("#ifndef", p2, line);
	ifstate_push(&lp->current, !macro_isdefined(line));
}

static
void
d_elif(struct lineplace *lp, struct place *p2, char *line)
{
	char *expr;
	struct place p3 = *p2;
	size_t oldlen;

	if (ifstate->seenelse) {
		complain(&lp->current, "#elif after #else");
		complain_fail();
	}

	if (ifstate->evertrue) {
		ifstate->curtrue = false;
	} else {
		expr = macroexpand(p2, line, strlen(line), true);

		oldlen = strlen(expr);
		uncomment(expr);
		/* trim to fit, so the malloc debugging won't complain */
		expr = dorealloc(expr, oldlen + 1, strlen(expr) + 1);

		ifstate->curtrue = eval(&p3, expr);
		ifstate->evertrue = ifstate->curtrue;
		dostrfree(expr);
	}
}

static
void
d_else(struct lineplace *lp, struct place *p2, char *line)
{
	(void)p2;
	(void)line;

	if (ifstate->seenelse) {
		complain(&lp->current,
			 "Multiple #else directives in one conditional");
		complain_fail();
	}

	ifstate->curtrue = !ifstate->evertrue;
	ifstate->evertrue = true;
	ifstate->seenelse = true;
}

static
void
d_endif(struct lineplace *lp, struct place *p2, char *line)
{
	(void)p2;
	(void)line;

	if (ifstate->prev == NULL) {
		complain(&lp->current, "Unmatched #endif");
		complain_fail();
	} else {
		ifstate_pop();
	}
}

////////////////////////////////////////////////////////////
// macros

static
void
d_define(struct lineplace *lp, struct place *p2, char *line)
{
	size_t pos, argpos;
	struct place p3, p4;

	(void)lp;

	/*
	 * line may be:
	 *    macro expansion
	 *    macro(arg, arg, ...) expansion
	 */

	pos = strcspn(line, " \t\f\v(");
	if (line[pos] == '(') {
		line[pos++] = '\0';
		argpos = pos;
		pos = pos + strcspn(line+pos, "()");
		if (line[pos] == '(') {
			p2->column += pos;
			complain(p2, "Left parenthesis in macro parameters");
			complain_fail();
			return;
		}
		if (line[pos] != ')') {
			p2->column += pos;
			complain(p2, "Unclosed macro parameter list");
			complain_fail();
			return;
		}
		line[pos++] = '\0';
#if 0
		if (!strchr(ws, line[pos])) {
			p2->column += pos;
			complain(p2, "Trash after macro parameter list");
			complain_fail();
			return;
		}
#endif
	} else if (line[pos] == '\0') {
		argpos = 0;
	} else {
		line[pos++] = '\0';
		argpos = 0;
	}

	pos += strspn(line+pos, ws);

	p3 = *p2;
	p3.column += argpos;

	p4 = *p2;
	p4.column += pos;

	if (argpos) {
		macro_define_params(p2, line, &p3,
				    line + argpos, &p4,
				    line + pos);
	} else {
		macro_define_plain(p2, line, &p4, line + pos);
	}
}

static
void
d_undef(struct lineplace *lp, struct place *p2, char *line)
{
	(void)lp;

	uncomment(line);
	oneword("#undef", p2, line);
	macro_undef(line);
}

////////////////////////////////////////////////////////////
// includes

static
bool
tryinclude(struct place *p, char *line)
{
	size_t len;

	len = strlen(line);
	if (len > 2 && line[0] == '"' && line[len-1] == '"') {
		line[len-1] = '\0';
		file_readquote(p, line+1);
		line[len-1] = '"';
		return true;
	}
	if (len > 2 && line[0] == '<' && line[len-1] == '>') {
		line[len-1] = '\0';
		file_readbracket(p, line+1);
		line[len-1] = '>';
		return true;
	}
	return false;
}

static
void
d_include(struct lineplace *lp, struct place *p2, char *line)
{
	char *text;
	size_t oldlen;

	uncomment(line);
	if (tryinclude(&lp->current, line)) {
		return;
	}
	text = macroexpand(p2, line, strlen(line), false);

	oldlen = strlen(text);
	uncomment(text);
	/* trim to fit, so the malloc debugging won't complain */
	text = dorealloc(text, oldlen + 1, strlen(text) + 1);

	if (tryinclude(&lp->current, text)) {
		dostrfree(text);
		return;
	}
	complain(&lp->current, "Illegal #include directive");
	complain(&lp->current, "Before macro expansion: #include %s", line);
	complain(&lp->current, "After macro expansion: #include %s", text);
	dostrfree(text);
	complain_fail();
}

static
void
d_line(struct lineplace *lp, struct place *p2, char *line)
{
	char *text;
	size_t oldlen;
	unsigned long val;
	char *moretext;
	size_t moretextlen;
	char *filename;

	text = macroexpand(p2, line, strlen(line), true);

	oldlen = strlen(text);
	uncomment(text);
	/* trim to fit, so the malloc debugging won't complain */
	text = dorealloc(text, oldlen + 1, strlen(text) + 1);

	/*
	 * What we should have here: either 1234 "file.c",
	 * or just 1234.
	 */

	errno = 0;
	val = strtoul(text, &moretext, 10);
	if (errno) {
		complain(&lp->current, "No line number in #line directive");
		goto fail;
	}
#if UINT_MAX < ULONG_MAX
	if (val > UINT_MAX) {
		complain(&lp->current,
			 "Line number in #line directive too large");
		goto fail;
	}
#endif
	moretext += strspn(moretext, ws);
	moretextlen = strlen(moretext);
	lp->current.column += (moretext - text);

	if (moretextlen > 2 &&
	    moretext[0] == '"' && moretext[moretextlen-1] == '"') {
		filename = dostrndup(moretext+1, moretextlen-2);
		place_setfile(&lp->nextline, filename);
		dostrfree(filename);
	}
	else if (moretextlen > 0) {
		complain(&lp->current,
			 "Invalid file name in #line directive");
		goto fail;
	}

	lp->nextline.line = val;
	dostrfree(text);
	return;

fail:
	complain(&lp->current, "Before macro expansion: #line %s", line);
	complain(&lp->current, "After macro expansion: #line %s", text);
	complain_fail();
	dostrfree(text);
}

////////////////////////////////////////////////////////////
// messages

static
void
d_warning(struct lineplace *lp, struct place *p2, char *line)
{
	char *msg;

	msg = macroexpand(p2, line, strlen(line), false);
	complain(&lp->current, "#warning: %s", msg);
	if (mode.werror) {
		complain_fail();
	}
	dostrfree(msg);
}

static
void
d_error(struct lineplace *lp, struct place *p2, char *line)
{
	char *msg;

	msg = macroexpand(p2, line, strlen(line), false);
	complain(&lp->current, "#error: %s", msg);
	complain_fail();
	dostrfree(msg);
}

////////////////////////////////////////////////////////////
// other

static
void
d_pragma(struct lineplace *lp, struct place *p2, char *line)
{
	(void)p2;

	complain(&lp->current, "#pragma %s", line);
	complain_fail();
}

////////////////////////////////////////////////////////////
// directive table

static const struct {
	const char *name;
	bool ifskip;
	void (*func)(struct lineplace *, struct place *, char *line);
} directives[] = {
	{ "define",  true,  d_define },
	{ "elif",    false, d_elif },
	{ "else",    false, d_else },
	{ "endif",   false, d_endif },
	{ "error",   true,  d_error },
	{ "if",      false, d_if },
	{ "ifdef",   false, d_ifdef },
	{ "ifndef",  false, d_ifndef },
	{ "include", true,  d_include },
	{ "line",    true,  d_line },
	{ "pragma",  true,  d_pragma },
	{ "undef",   true,  d_undef },
	{ "warning", true,  d_warning },
};
static const unsigned numdirectives = HOWMANY(directives);

static
void
directive_gotdirective(struct lineplace *lp, char *line)
{
	struct place p2;
	size_t len, skip;
	unsigned i;

	p2 = lp->current;
	for (i=0; i<numdirectives; i++) {
		len = strlen(directives[i].name);
		if (!strncmp(line, directives[i].name, len) &&
		    strchr(ws, line[len])) {
			if (directives[i].ifskip && !ifstate->curtrue) {
				return;
			}
			skip = len + strspn(line+len, ws);
			p2.column += skip;
			line += skip;

			len = strlen(line);
			len = notrailingws(line, len);
			if (len < strlen(line)) {
				line[len] = '\0';
			}
			directives[i].func(lp, &p2, line);
			return;
		}
	}
	/* ugh. allow # by itself, including with a comment after it */
	uncomment(line);
	if (line[0] == '\0') {
		return;
	}

	skip = strcspn(line, ws);
	complain(&lp->current, "Unknown directive #%.*s", (int)skip, line);
	complain_fail();
}

/*
 * Check for nested comment delimiters in LINE.
 */
static
size_t
directive_scancomments(const struct lineplace *lp, char *line, size_t len)
{
	size_t pos;
	bool incomment;
	struct place p2;

	p2 = lp->current;
	incomment = 0;
	for (pos = 0; pos+1 < len; pos++) {
		if (line[pos] == '/' && line[pos+1] == '*') {
			if (incomment) {
				complain(&p2, "Warning: %c%c within comment",
					 '/', '*');
				if (mode.werror) {
					complain_failed();
				}
			} else {
				incomment = true;
			}
			pos++;
		} else if (line[pos] == '*' && line[pos+1] == '/') {
			if (incomment) {
				incomment = false;
			} else {
				/* stray end-comment; should we care? */
			}
			pos++;
		}
		if (line[pos] == '\n') {
			p2.line++;
			p2.column = 0;
		} else {
			p2.column++;
		}
	}

	/* multiline comments are supposed to arrive in a single buffer */
	assert(!incomment);
	return len;
}

void
directive_gotline(struct lineplace *lp, char *line, size_t len)
{
	size_t skip;

	if (warns.nestcomment) {
		directive_scancomments(lp, line, len);
	}

	/* check if we have a directive line (# exactly in column 0) */
	if (len > 0 && line[0] == '#') {
		skip = 1 + strspn(line + 1, ws);
		assert(skip <= len);
		lp->current.column += skip;
		assert(line[len] == '\0');
		directive_gotdirective(lp, line+skip /*, length = len-skip */);
		lp->current.column += len-skip;
	} else if (ifstate->curtrue) {
		macro_sendline(&lp->current, line, len);
		lp->current.column += len;
	}
}

void
directive_goteof(struct place *p)
{
	while (ifstate->prev != NULL) {
		complain(p, "Missing #endif");
		complain(&ifstate->startplace, "...opened at this point");
		complain_failed();
		ifstate_pop();
	}
	macro_sendeof(p);
}

////////////////////////////////////////////////////////////
// module initialization

void
directive_init(void)
{
	ifstate = ifstate_create(NULL, NULL, true);
}

void
directive_cleanup(void)
{
	assert(ifstate->prev == NULL);
	ifstate_destroy(ifstate);
	ifstate = NULL;
}