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-rw-r--r--packages/linux/linux-2.6.18/kbuild-add-unifdef.patch1020
1 files changed, 1020 insertions, 0 deletions
diff --git a/packages/linux/linux-2.6.18/kbuild-add-unifdef.patch b/packages/linux/linux-2.6.18/kbuild-add-unifdef.patch
new file mode 100644
index 0000000000..78922a98af
--- /dev/null
+++ b/packages/linux/linux-2.6.18/kbuild-add-unifdef.patch
@@ -0,0 +1,1020 @@
+From 01f1c8799ad8b23c190d59cf1c9e28e6fed390a4 Mon Sep 17 00:00:00 2001
+From: Sam Ravnborg <sam@mars.ravnborg.org>
+Date: Sun, 23 Jul 2006 20:39:59 +0200
+Subject: [PATCH] kbuild: add unifdef
+
+This patch contains a raw copy of unifdef.c
+Next patch will modify it and add infrastructure to use it
+Adding unifdef to the kernel is acked by the author.
+
+The reason to add unifdef as part of the kernel source is that it is not
+yet a common utility on most distributions.
+
+Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
+---
+ scripts/unifdef.c | 998 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 998 insertions(+)
+
+Index: linux-2.6.18-avr32/scripts/unifdef.c
+===================================================================
+--- /dev/null 1970-01-01 00:00:00.000000000 +0000
++++ linux-2.6.18-avr32/scripts/unifdef.c 2006-10-30 15:59:47.000000000 +0100
+@@ -0,0 +1,998 @@
++/*
++ * Copyright (c) 2002 - 2005 Tony Finch <dot@dotat.at>. All rights reserved.
++ *
++ * This code is derived from software contributed to Berkeley by Dave Yost.
++ * It was rewritten to support ANSI C by Tony Finch. The original version of
++ * unifdef carried the following copyright notice. None of its code remains
++ * in this version (though some of the names remain).
++ *
++ * Copyright (c) 1985, 1993
++ * The Regents of the University of California. All rights reserved.
++ *
++ * 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 AUTHOR 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 AUTHOR 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 <sys/cdefs.h>
++
++#ifndef lint
++#if 0
++static const char copyright[] =
++"@(#) Copyright (c) 1985, 1993\n\
++ The Regents of the University of California. All rights reserved.\n";
++#endif
++#ifdef __IDSTRING
++__IDSTRING(Berkeley, "@(#)unifdef.c 8.1 (Berkeley) 6/6/93");
++__IDSTRING(NetBSD, "$NetBSD: unifdef.c,v 1.8 2000/07/03 02:51:36 matt Exp $");
++__IDSTRING(dotat, "$dotat: things/unifdef.c,v 1.171 2005/03/08 12:38:48 fanf2 Exp $");
++#endif
++#endif /* not lint */
++#ifdef __FBSDID
++__FBSDID("$FreeBSD: /repoman/r/ncvs/src/usr.bin/unifdef/unifdef.c,v 1.20 2005/05/21 09:55:09 ru Exp $");
++#endif
++
++/*
++ * unifdef - remove ifdef'ed lines
++ *
++ * Wishlist:
++ * provide an option which will append the name of the
++ * appropriate symbol after #else's and #endif's
++ * provide an option which will check symbols after
++ * #else's and #endif's to see that they match their
++ * corresponding #ifdef or #ifndef
++ *
++ * The first two items above require better buffer handling, which would
++ * also make it possible to handle all "dodgy" directives correctly.
++ */
++
++#include <ctype.h>
++#include <err.h>
++#include <stdarg.h>
++#include <stdbool.h>
++#include <stdio.h>
++#include <stdlib.h>
++#include <string.h>
++#include <unistd.h>
++
++size_t strlcpy(char *dst, const char *src, size_t siz);
++
++/* types of input lines: */
++typedef enum {
++ LT_TRUEI, /* a true #if with ignore flag */
++ LT_FALSEI, /* a false #if with ignore flag */
++ LT_IF, /* an unknown #if */
++ LT_TRUE, /* a true #if */
++ LT_FALSE, /* a false #if */
++ LT_ELIF, /* an unknown #elif */
++ LT_ELTRUE, /* a true #elif */
++ LT_ELFALSE, /* a false #elif */
++ LT_ELSE, /* #else */
++ LT_ENDIF, /* #endif */
++ LT_DODGY, /* flag: directive is not on one line */
++ LT_DODGY_LAST = LT_DODGY + LT_ENDIF,
++ LT_PLAIN, /* ordinary line */
++ LT_EOF, /* end of file */
++ LT_COUNT
++} Linetype;
++
++static char const * const linetype_name[] = {
++ "TRUEI", "FALSEI", "IF", "TRUE", "FALSE",
++ "ELIF", "ELTRUE", "ELFALSE", "ELSE", "ENDIF",
++ "DODGY TRUEI", "DODGY FALSEI",
++ "DODGY IF", "DODGY TRUE", "DODGY FALSE",
++ "DODGY ELIF", "DODGY ELTRUE", "DODGY ELFALSE",
++ "DODGY ELSE", "DODGY ENDIF",
++ "PLAIN", "EOF"
++};
++
++/* state of #if processing */
++typedef enum {
++ IS_OUTSIDE,
++ IS_FALSE_PREFIX, /* false #if followed by false #elifs */
++ IS_TRUE_PREFIX, /* first non-false #(el)if is true */
++ IS_PASS_MIDDLE, /* first non-false #(el)if is unknown */
++ IS_FALSE_MIDDLE, /* a false #elif after a pass state */
++ IS_TRUE_MIDDLE, /* a true #elif after a pass state */
++ IS_PASS_ELSE, /* an else after a pass state */
++ IS_FALSE_ELSE, /* an else after a true state */
++ IS_TRUE_ELSE, /* an else after only false states */
++ IS_FALSE_TRAILER, /* #elifs after a true are false */
++ IS_COUNT
++} Ifstate;
++
++static char const * const ifstate_name[] = {
++ "OUTSIDE", "FALSE_PREFIX", "TRUE_PREFIX",
++ "PASS_MIDDLE", "FALSE_MIDDLE", "TRUE_MIDDLE",
++ "PASS_ELSE", "FALSE_ELSE", "TRUE_ELSE",
++ "FALSE_TRAILER"
++};
++
++/* state of comment parser */
++typedef enum {
++ NO_COMMENT = false, /* outside a comment */
++ C_COMMENT, /* in a comment like this one */
++ CXX_COMMENT, /* between // and end of line */
++ STARTING_COMMENT, /* just after slash-backslash-newline */
++ FINISHING_COMMENT, /* star-backslash-newline in a C comment */
++ CHAR_LITERAL, /* inside '' */
++ STRING_LITERAL /* inside "" */
++} Comment_state;
++
++static char const * const comment_name[] = {
++ "NO", "C", "CXX", "STARTING", "FINISHING", "CHAR", "STRING"
++};
++
++/* state of preprocessor line parser */
++typedef enum {
++ LS_START, /* only space and comments on this line */
++ LS_HASH, /* only space, comments, and a hash */
++ LS_DIRTY /* this line can't be a preprocessor line */
++} Line_state;
++
++static char const * const linestate_name[] = {
++ "START", "HASH", "DIRTY"
++};
++
++/*
++ * Minimum translation limits from ISO/IEC 9899:1999 5.2.4.1
++ */
++#define MAXDEPTH 64 /* maximum #if nesting */
++#define MAXLINE 4096 /* maximum length of line */
++#define MAXSYMS 4096 /* maximum number of symbols */
++
++/*
++ * Sometimes when editing a keyword the replacement text is longer, so
++ * we leave some space at the end of the tline buffer to accommodate this.
++ */
++#define EDITSLOP 10
++
++/*
++ * Globals.
++ */
++
++static bool complement; /* -c: do the complement */
++static bool debugging; /* -d: debugging reports */
++static bool iocccok; /* -e: fewer IOCCC errors */
++static bool killconsts; /* -k: eval constant #ifs */
++static bool lnblank; /* -l: blank deleted lines */
++static bool lnnum; /* -n: add #line directives */
++static bool symlist; /* -s: output symbol list */
++static bool text; /* -t: this is a text file */
++
++static const char *symname[MAXSYMS]; /* symbol name */
++static const char *value[MAXSYMS]; /* -Dsym=value */
++static bool ignore[MAXSYMS]; /* -iDsym or -iUsym */
++static int nsyms; /* number of symbols */
++
++static FILE *input; /* input file pointer */
++static const char *filename; /* input file name */
++static int linenum; /* current line number */
++
++static char tline[MAXLINE+EDITSLOP];/* input buffer plus space */
++static char *keyword; /* used for editing #elif's */
++
++static Comment_state incomment; /* comment parser state */
++static Line_state linestate; /* #if line parser state */
++static Ifstate ifstate[MAXDEPTH]; /* #if processor state */
++static bool ignoring[MAXDEPTH]; /* ignore comments state */
++static int stifline[MAXDEPTH]; /* start of current #if */
++static int depth; /* current #if nesting */
++static int delcount; /* count of deleted lines */
++static bool keepthis; /* don't delete constant #if */
++
++static int exitstat; /* program exit status */
++
++static void addsym(bool, bool, char *);
++static void debug(const char *, ...);
++static void done(void);
++static void error(const char *);
++static int findsym(const char *);
++static void flushline(bool);
++static Linetype getline(void);
++static Linetype ifeval(const char **);
++static void ignoreoff(void);
++static void ignoreon(void);
++static void keywordedit(const char *);
++static void nest(void);
++static void process(void);
++static const char *skipcomment(const char *);
++static const char *skipsym(const char *);
++static void state(Ifstate);
++static int strlcmp(const char *, const char *, size_t);
++static void unnest(void);
++static void usage(void);
++
++#define endsym(c) (!isalpha((unsigned char)c) && !isdigit((unsigned char)c) && c != '_')
++
++/*
++ * The main program.
++ */
++int
++main(int argc, char *argv[])
++{
++ int opt;
++
++ while ((opt = getopt(argc, argv, "i:D:U:I:cdeklnst")) != -1)
++ switch (opt) {
++ case 'i': /* treat stuff controlled by these symbols as text */
++ /*
++ * For strict backwards-compatibility the U or D
++ * should be immediately after the -i but it doesn't
++ * matter much if we relax that requirement.
++ */
++ opt = *optarg++;
++ if (opt == 'D')
++ addsym(true, true, optarg);
++ else if (opt == 'U')
++ addsym(true, false, optarg);
++ else
++ usage();
++ break;
++ case 'D': /* define a symbol */
++ addsym(false, true, optarg);
++ break;
++ case 'U': /* undef a symbol */
++ addsym(false, false, optarg);
++ break;
++ case 'I':
++ /* no-op for compatibility with cpp */
++ break;
++ case 'c': /* treat -D as -U and vice versa */
++ complement = true;
++ break;
++ case 'd':
++ debugging = true;
++ break;
++ case 'e': /* fewer errors from dodgy lines */
++ iocccok = true;
++ break;
++ case 'k': /* process constant #ifs */
++ killconsts = true;
++ break;
++ case 'l': /* blank deleted lines instead of omitting them */
++ lnblank = true;
++ break;
++ case 'n': /* add #line directive after deleted lines */
++ lnnum = true;
++ break;
++ case 's': /* only output list of symbols that control #ifs */
++ symlist = true;
++ break;
++ case 't': /* don't parse C comments */
++ text = true;
++ break;
++ default:
++ usage();
++ }
++ argc -= optind;
++ argv += optind;
++ if (argc > 1) {
++ errx(2, "can only do one file");
++ } else if (argc == 1 && strcmp(*argv, "-") != 0) {
++ filename = *argv;
++ input = fopen(filename, "r");
++ if (input == NULL)
++ err(2, "can't open %s", filename);
++ } else {
++ filename = "[stdin]";
++ input = stdin;
++ }
++ process();
++ abort(); /* bug */
++}
++
++static void
++usage(void)
++{
++ fprintf(stderr, "usage: unifdef [-cdeklnst] [-Ipath]"
++ " [-Dsym[=val]] [-Usym] [-iDsym[=val]] [-iUsym] ... [file]\n");
++ exit(2);
++}
++
++/*
++ * A state transition function alters the global #if processing state
++ * in a particular way. The table below is indexed by the current
++ * processing state and the type of the current line.
++ *
++ * Nesting is handled by keeping a stack of states; some transition
++ * functions increase or decrease the depth. They also maintain the
++ * ignore state on a stack. In some complicated cases they have to
++ * alter the preprocessor directive, as follows.
++ *
++ * When we have processed a group that starts off with a known-false
++ * #if/#elif sequence (which has therefore been deleted) followed by a
++ * #elif that we don't understand and therefore must keep, we edit the
++ * latter into a #if to keep the nesting correct.
++ *
++ * When we find a true #elif in a group, the following block will
++ * always be kept and the rest of the sequence after the next #elif or
++ * #else will be discarded. We edit the #elif into a #else and the
++ * following directive to #endif since this has the desired behaviour.
++ *
++ * "Dodgy" directives are split across multiple lines, the most common
++ * example being a multi-line comment hanging off the right of the
++ * directive. We can handle them correctly only if there is no change
++ * from printing to dropping (or vice versa) caused by that directive.
++ * If the directive is the first of a group we have a choice between
++ * failing with an error, or passing it through unchanged instead of
++ * evaluating it. The latter is not the default to avoid questions from
++ * users about unifdef unexpectedly leaving behind preprocessor directives.
++ */
++typedef void state_fn(void);
++
++/* report an error */
++static void Eelif (void) { error("Inappropriate #elif"); }
++static void Eelse (void) { error("Inappropriate #else"); }
++static void Eendif(void) { error("Inappropriate #endif"); }
++static void Eeof (void) { error("Premature EOF"); }
++static void Eioccc(void) { error("Obfuscated preprocessor control line"); }
++/* plain line handling */
++static void print (void) { flushline(true); }
++static void drop (void) { flushline(false); }
++/* output lacks group's start line */
++static void Strue (void) { drop(); ignoreoff(); state(IS_TRUE_PREFIX); }
++static void Sfalse(void) { drop(); ignoreoff(); state(IS_FALSE_PREFIX); }
++static void Selse (void) { drop(); state(IS_TRUE_ELSE); }
++/* print/pass this block */
++static void Pelif (void) { print(); ignoreoff(); state(IS_PASS_MIDDLE); }
++static void Pelse (void) { print(); state(IS_PASS_ELSE); }
++static void Pendif(void) { print(); unnest(); }
++/* discard this block */
++static void Dfalse(void) { drop(); ignoreoff(); state(IS_FALSE_TRAILER); }
++static void Delif (void) { drop(); ignoreoff(); state(IS_FALSE_MIDDLE); }
++static void Delse (void) { drop(); state(IS_FALSE_ELSE); }
++static void Dendif(void) { drop(); unnest(); }
++/* first line of group */
++static void Fdrop (void) { nest(); Dfalse(); }
++static void Fpass (void) { nest(); Pelif(); }
++static void Ftrue (void) { nest(); Strue(); }
++static void Ffalse(void) { nest(); Sfalse(); }
++/* variable pedantry for obfuscated lines */
++static void Oiffy (void) { if (!iocccok) Eioccc(); Fpass(); ignoreon(); }
++static void Oif (void) { if (!iocccok) Eioccc(); Fpass(); }
++static void Oelif (void) { if (!iocccok) Eioccc(); Pelif(); }
++/* ignore comments in this block */
++static void Idrop (void) { Fdrop(); ignoreon(); }
++static void Itrue (void) { Ftrue(); ignoreon(); }
++static void Ifalse(void) { Ffalse(); ignoreon(); }
++/* edit this line */
++static void Mpass (void) { strncpy(keyword, "if ", 4); Pelif(); }
++static void Mtrue (void) { keywordedit("else\n"); state(IS_TRUE_MIDDLE); }
++static void Melif (void) { keywordedit("endif\n"); state(IS_FALSE_TRAILER); }
++static void Melse (void) { keywordedit("endif\n"); state(IS_FALSE_ELSE); }
++
++static state_fn * const trans_table[IS_COUNT][LT_COUNT] = {
++/* IS_OUTSIDE */
++{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Eendif,
++ Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eendif,
++ print, done },
++/* IS_FALSE_PREFIX */
++{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Strue, Sfalse,Selse, Dendif,
++ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Eioccc,Eioccc,Eioccc,Eioccc,
++ drop, Eeof },
++/* IS_TRUE_PREFIX */
++{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Dfalse,Dfalse,Dfalse,Delse, Dendif,
++ Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc,
++ print, Eeof },
++/* IS_PASS_MIDDLE */
++{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Pelif, Mtrue, Delif, Pelse, Pendif,
++ Oiffy, Oiffy, Fpass, Oif, Oif, Pelif, Oelif, Oelif, Pelse, Pendif,
++ print, Eeof },
++/* IS_FALSE_MIDDLE */
++{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Pelif, Mtrue, Delif, Pelse, Pendif,
++ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc,
++ drop, Eeof },
++/* IS_TRUE_MIDDLE */
++{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Melif, Melif, Melif, Melse, Pendif,
++ Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Pendif,
++ print, Eeof },
++/* IS_PASS_ELSE */
++{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Pendif,
++ Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Pendif,
++ print, Eeof },
++/* IS_FALSE_ELSE */
++{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Dendif,
++ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Eioccc,
++ drop, Eeof },
++/* IS_TRUE_ELSE */
++{ Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Dendif,
++ Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eioccc,
++ print, Eeof },
++/* IS_FALSE_TRAILER */
++{ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Dendif,
++ Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Eioccc,
++ drop, Eeof }
++/*TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF
++ TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF (DODGY)
++ PLAIN EOF */
++};
++
++/*
++ * State machine utility functions
++ */
++static void
++done(void)
++{
++ if (incomment)
++ error("EOF in comment");
++ exit(exitstat);
++}
++static void
++ignoreoff(void)
++{
++ if (depth == 0)
++ abort(); /* bug */
++ ignoring[depth] = ignoring[depth-1];
++}
++static void
++ignoreon(void)
++{
++ ignoring[depth] = true;
++}
++static void
++keywordedit(const char *replacement)
++{
++ strlcpy(keyword, replacement, tline + sizeof(tline) - keyword);
++ print();
++}
++static void
++nest(void)
++{
++ depth += 1;
++ if (depth >= MAXDEPTH)
++ error("Too many levels of nesting");
++ stifline[depth] = linenum;
++}
++static void
++unnest(void)
++{
++ if (depth == 0)
++ abort(); /* bug */
++ depth -= 1;
++}
++static void
++state(Ifstate is)
++{
++ ifstate[depth] = is;
++}
++
++/*
++ * Write a line to the output or not, according to command line options.
++ */
++static void
++flushline(bool keep)
++{
++ if (symlist)
++ return;
++ if (keep ^ complement) {
++ if (lnnum && delcount > 0)
++ printf("#line %d\n", linenum);
++ fputs(tline, stdout);
++ delcount = 0;
++ } else {
++ if (lnblank)
++ putc('\n', stdout);
++ exitstat = 1;
++ delcount += 1;
++ }
++}
++
++/*
++ * The driver for the state machine.
++ */
++static void
++process(void)
++{
++ Linetype lineval;
++
++ for (;;) {
++ linenum++;
++ lineval = getline();
++ trans_table[ifstate[depth]][lineval]();
++ debug("process %s -> %s depth %d",
++ linetype_name[lineval],
++ ifstate_name[ifstate[depth]], depth);
++ }
++}
++
++/*
++ * Parse a line and determine its type. We keep the preprocessor line
++ * parser state between calls in the global variable linestate, with
++ * help from skipcomment().
++ */
++static Linetype
++getline(void)
++{
++ const char *cp;
++ int cursym;
++ int kwlen;
++ Linetype retval;
++ Comment_state wascomment;
++
++ if (fgets(tline, MAXLINE, input) == NULL)
++ return (LT_EOF);
++ retval = LT_PLAIN;
++ wascomment = incomment;
++ cp = skipcomment(tline);
++ if (linestate == LS_START) {
++ if (*cp == '#') {
++ linestate = LS_HASH;
++ cp = skipcomment(cp + 1);
++ } else if (*cp != '\0')
++ linestate = LS_DIRTY;
++ }
++ if (!incomment && linestate == LS_HASH) {
++ keyword = tline + (cp - tline);
++ cp = skipsym(cp);
++ kwlen = cp - keyword;
++ /* no way can we deal with a continuation inside a keyword */
++ if (strncmp(cp, "\\\n", 2) == 0)
++ Eioccc();
++ if (strlcmp("ifdef", keyword, kwlen) == 0 ||
++ strlcmp("ifndef", keyword, kwlen) == 0) {
++ cp = skipcomment(cp);
++ if ((cursym = findsym(cp)) < 0)
++ retval = LT_IF;
++ else {
++ retval = (keyword[2] == 'n')
++ ? LT_FALSE : LT_TRUE;
++ if (value[cursym] == NULL)
++ retval = (retval == LT_TRUE)
++ ? LT_FALSE : LT_TRUE;
++ if (ignore[cursym])
++ retval = (retval == LT_TRUE)
++ ? LT_TRUEI : LT_FALSEI;
++ }
++ cp = skipsym(cp);
++ } else if (strlcmp("if", keyword, kwlen) == 0)
++ retval = ifeval(&cp);
++ else if (strlcmp("elif", keyword, kwlen) == 0)
++ retval = ifeval(&cp) - LT_IF + LT_ELIF;
++ else if (strlcmp("else", keyword, kwlen) == 0)
++ retval = LT_ELSE;
++ else if (strlcmp("endif", keyword, kwlen) == 0)
++ retval = LT_ENDIF;
++ else {
++ linestate = LS_DIRTY;
++ retval = LT_PLAIN;
++ }
++ cp = skipcomment(cp);
++ if (*cp != '\0') {
++ linestate = LS_DIRTY;
++ if (retval == LT_TRUE || retval == LT_FALSE ||
++ retval == LT_TRUEI || retval == LT_FALSEI)
++ retval = LT_IF;
++ if (retval == LT_ELTRUE || retval == LT_ELFALSE)
++ retval = LT_ELIF;
++ }
++ if (retval != LT_PLAIN && (wascomment || incomment)) {
++ retval += LT_DODGY;
++ if (incomment)
++ linestate = LS_DIRTY;
++ }
++ /* skipcomment should have changed the state */
++ if (linestate == LS_HASH)
++ abort(); /* bug */
++ }
++ if (linestate == LS_DIRTY) {
++ while (*cp != '\0')
++ cp = skipcomment(cp + 1);
++ }
++ debug("parser %s comment %s line",
++ comment_name[incomment], linestate_name[linestate]);
++ return (retval);
++}
++
++/*
++ * These are the binary operators that are supported by the expression
++ * evaluator. Note that if support for division is added then we also
++ * need short-circuiting booleans because of divide-by-zero.
++ */
++static int op_lt(int a, int b) { return (a < b); }
++static int op_gt(int a, int b) { return (a > b); }
++static int op_le(int a, int b) { return (a <= b); }
++static int op_ge(int a, int b) { return (a >= b); }
++static int op_eq(int a, int b) { return (a == b); }
++static int op_ne(int a, int b) { return (a != b); }
++static int op_or(int a, int b) { return (a || b); }
++static int op_and(int a, int b) { return (a && b); }
++
++/*
++ * An evaluation function takes three arguments, as follows: (1) a pointer to
++ * an element of the precedence table which lists the operators at the current
++ * level of precedence; (2) a pointer to an integer which will receive the
++ * value of the expression; and (3) a pointer to a char* that points to the
++ * expression to be evaluated and that is updated to the end of the expression
++ * when evaluation is complete. The function returns LT_FALSE if the value of
++ * the expression is zero, LT_TRUE if it is non-zero, or LT_IF if the
++ * expression could not be evaluated.
++ */
++struct ops;
++
++typedef Linetype eval_fn(const struct ops *, int *, const char **);
++
++static eval_fn eval_table, eval_unary;
++
++/*
++ * The precedence table. Expressions involving binary operators are evaluated
++ * in a table-driven way by eval_table. When it evaluates a subexpression it
++ * calls the inner function with its first argument pointing to the next
++ * element of the table. Innermost expressions have special non-table-driven
++ * handling.
++ */
++static const struct ops {
++ eval_fn *inner;
++ struct op {
++ const char *str;
++ int (*fn)(int, int);
++ } op[5];
++} eval_ops[] = {
++ { eval_table, { { "||", op_or } } },
++ { eval_table, { { "&&", op_and } } },
++ { eval_table, { { "==", op_eq },
++ { "!=", op_ne } } },
++ { eval_unary, { { "<=", op_le },
++ { ">=", op_ge },
++ { "<", op_lt },
++ { ">", op_gt } } }
++};
++
++/*
++ * Function for evaluating the innermost parts of expressions,
++ * viz. !expr (expr) defined(symbol) symbol number
++ * We reset the keepthis flag when we find a non-constant subexpression.
++ */
++static Linetype
++eval_unary(const struct ops *ops, int *valp, const char **cpp)
++{
++ const char *cp;
++ char *ep;
++ int sym;
++
++ cp = skipcomment(*cpp);
++ if (*cp == '!') {
++ debug("eval%d !", ops - eval_ops);
++ cp++;
++ if (eval_unary(ops, valp, &cp) == LT_IF)
++ return (LT_IF);
++ *valp = !*valp;
++ } else if (*cp == '(') {
++ cp++;
++ debug("eval%d (", ops - eval_ops);
++ if (eval_table(eval_ops, valp, &cp) == LT_IF)
++ return (LT_IF);
++ cp = skipcomment(cp);
++ if (*cp++ != ')')
++ return (LT_IF);
++ } else if (isdigit((unsigned char)*cp)) {
++ debug("eval%d number", ops - eval_ops);
++ *valp = strtol(cp, &ep, 0);
++ cp = skipsym(cp);
++ } else if (strncmp(cp, "defined", 7) == 0 && endsym(cp[7])) {
++ cp = skipcomment(cp+7);
++ debug("eval%d defined", ops - eval_ops);
++ if (*cp++ != '(')
++ return (LT_IF);
++ cp = skipcomment(cp);
++ sym = findsym(cp);
++ if (sym < 0)
++ return (LT_IF);
++ *valp = (value[sym] != NULL);
++ cp = skipsym(cp);
++ cp = skipcomment(cp);
++ if (*cp++ != ')')
++ return (LT_IF);
++ keepthis = false;
++ } else if (!endsym(*cp)) {
++ debug("eval%d symbol", ops - eval_ops);
++ sym = findsym(cp);
++ if (sym < 0)
++ return (LT_IF);
++ if (value[sym] == NULL)
++ *valp = 0;
++ else {
++ *valp = strtol(value[sym], &ep, 0);
++ if (*ep != '\0' || ep == value[sym])
++ return (LT_IF);
++ }
++ cp = skipsym(cp);
++ keepthis = false;
++ } else {
++ debug("eval%d bad expr", ops - eval_ops);
++ return (LT_IF);
++ }
++
++ *cpp = cp;
++ debug("eval%d = %d", ops - eval_ops, *valp);
++ return (*valp ? LT_TRUE : LT_FALSE);
++}
++
++/*
++ * Table-driven evaluation of binary operators.
++ */
++static Linetype
++eval_table(const struct ops *ops, int *valp, const char **cpp)
++{
++ const struct op *op;
++ const char *cp;
++ int val;
++
++ debug("eval%d", ops - eval_ops);
++ cp = *cpp;
++ if (ops->inner(ops+1, valp, &cp) == LT_IF)
++ return (LT_IF);
++ for (;;) {
++ cp = skipcomment(cp);
++ for (op = ops->op; op->str != NULL; op++)
++ if (strncmp(cp, op->str, strlen(op->str)) == 0)
++ break;
++ if (op->str == NULL)
++ break;
++ cp += strlen(op->str);
++ debug("eval%d %s", ops - eval_ops, op->str);
++ if (ops->inner(ops+1, &val, &cp) == LT_IF)
++ return (LT_IF);
++ *valp = op->fn(*valp, val);
++ }
++
++ *cpp = cp;
++ debug("eval%d = %d", ops - eval_ops, *valp);
++ return (*valp ? LT_TRUE : LT_FALSE);
++}
++
++/*
++ * Evaluate the expression on a #if or #elif line. If we can work out
++ * the result we return LT_TRUE or LT_FALSE accordingly, otherwise we
++ * return just a generic LT_IF.
++ */
++static Linetype
++ifeval(const char **cpp)
++{
++ int ret;
++ int val;
++
++ debug("eval %s", *cpp);
++ keepthis = killconsts ? false : true;
++ ret = eval_table(eval_ops, &val, cpp);
++ debug("eval = %d", val);
++ return (keepthis ? LT_IF : ret);
++}
++
++/*
++ * Skip over comments, strings, and character literals and stop at the
++ * next character position that is not whitespace. Between calls we keep
++ * the comment state in the global variable incomment, and we also adjust
++ * the global variable linestate when we see a newline.
++ * XXX: doesn't cope with the buffer splitting inside a state transition.
++ */
++static const char *
++skipcomment(const char *cp)
++{
++ if (text || ignoring[depth]) {
++ for (; isspace((unsigned char)*cp); cp++)
++ if (*cp == '\n')
++ linestate = LS_START;
++ return (cp);
++ }
++ while (*cp != '\0')
++ /* don't reset to LS_START after a line continuation */
++ if (strncmp(cp, "\\\n", 2) == 0)
++ cp += 2;
++ else switch (incomment) {
++ case NO_COMMENT:
++ if (strncmp(cp, "/\\\n", 3) == 0) {
++ incomment = STARTING_COMMENT;
++ cp += 3;
++ } else if (strncmp(cp, "/*", 2) == 0) {
++ incomment = C_COMMENT;
++ cp += 2;
++ } else if (strncmp(cp, "//", 2) == 0) {
++ incomment = CXX_COMMENT;
++ cp += 2;
++ } else if (strncmp(cp, "\'", 1) == 0) {
++ incomment = CHAR_LITERAL;
++ linestate = LS_DIRTY;
++ cp += 1;
++ } else if (strncmp(cp, "\"", 1) == 0) {
++ incomment = STRING_LITERAL;
++ linestate = LS_DIRTY;
++ cp += 1;
++ } else if (strncmp(cp, "\n", 1) == 0) {
++ linestate = LS_START;
++ cp += 1;
++ } else if (strchr(" \t", *cp) != NULL) {
++ cp += 1;
++ } else
++ return (cp);
++ continue;
++ case CXX_COMMENT:
++ if (strncmp(cp, "\n", 1) == 0) {
++ incomment = NO_COMMENT;
++ linestate = LS_START;
++ }
++ cp += 1;
++ continue;
++ case CHAR_LITERAL:
++ case STRING_LITERAL:
++ if ((incomment == CHAR_LITERAL && cp[0] == '\'') ||
++ (incomment == STRING_LITERAL && cp[0] == '\"')) {
++ incomment = NO_COMMENT;
++ cp += 1;
++ } else if (cp[0] == '\\') {
++ if (cp[1] == '\0')
++ cp += 1;
++ else
++ cp += 2;
++ } else if (strncmp(cp, "\n", 1) == 0) {
++ if (incomment == CHAR_LITERAL)
++ error("unterminated char literal");
++ else
++ error("unterminated string literal");
++ } else
++ cp += 1;
++ continue;
++ case C_COMMENT:
++ if (strncmp(cp, "*\\\n", 3) == 0) {
++ incomment = FINISHING_COMMENT;
++ cp += 3;
++ } else if (strncmp(cp, "*/", 2) == 0) {
++ incomment = NO_COMMENT;
++ cp += 2;
++ } else
++ cp += 1;
++ continue;
++ case STARTING_COMMENT:
++ if (*cp == '*') {
++ incomment = C_COMMENT;
++ cp += 1;
++ } else if (*cp == '/') {
++ incomment = CXX_COMMENT;
++ cp += 1;
++ } else {
++ incomment = NO_COMMENT;
++ linestate = LS_DIRTY;
++ }
++ continue;
++ case FINISHING_COMMENT:
++ if (*cp == '/') {
++ incomment = NO_COMMENT;
++ cp += 1;
++ } else
++ incomment = C_COMMENT;
++ continue;
++ default:
++ abort(); /* bug */
++ }
++ return (cp);
++}
++
++/*
++ * Skip over an identifier.
++ */
++static const char *
++skipsym(const char *cp)
++{
++ while (!endsym(*cp))
++ ++cp;
++ return (cp);
++}
++
++/*
++ * Look for the symbol in the symbol table. If is is found, we return
++ * the symbol table index, else we return -1.
++ */
++static int
++findsym(const char *str)
++{
++ const char *cp;
++ int symind;
++
++ cp = skipsym(str);
++ if (cp == str)
++ return (-1);
++ if (symlist) {
++ printf("%.*s\n", (int)(cp-str), str);
++ /* we don't care about the value of the symbol */
++ return (0);
++ }
++ for (symind = 0; symind < nsyms; ++symind) {
++ if (strlcmp(symname[symind], str, cp-str) == 0) {
++ debug("findsym %s %s", symname[symind],
++ value[symind] ? value[symind] : "");
++ return (symind);
++ }
++ }
++ return (-1);
++}
++
++/*
++ * Add a symbol to the symbol table.
++ */
++static void
++addsym(bool ignorethis, bool definethis, char *sym)
++{
++ int symind;
++ char *val;
++
++ symind = findsym(sym);
++ if (symind < 0) {
++ if (nsyms >= MAXSYMS)
++ errx(2, "too many symbols");
++ symind = nsyms++;
++ }
++ symname[symind] = sym;
++ ignore[symind] = ignorethis;
++ val = sym + (skipsym(sym) - sym);
++ if (definethis) {
++ if (*val == '=') {
++ value[symind] = val+1;
++ *val = '\0';
++ } else if (*val == '\0')
++ value[symind] = "";
++ else
++ usage();
++ } else {
++ if (*val != '\0')
++ usage();
++ value[symind] = NULL;
++ }
++}
++
++/*
++ * Compare s with n characters of t.
++ * The same as strncmp() except that it checks that s[n] == '\0'.
++ */
++static int
++strlcmp(const char *s, const char *t, size_t n)
++{
++ while (n-- && *t != '\0')
++ if (*s != *t)
++ return ((unsigned char)*s - (unsigned char)*t);
++ else
++ ++s, ++t;
++ return ((unsigned char)*s);
++}
++
++/*
++ * Diagnostics.
++ */
++static void
++debug(const char *msg, ...)
++{
++ va_list ap;
++
++ if (debugging) {
++ va_start(ap, msg);
++ vwarnx(msg, ap);
++ va_end(ap);
++ }
++}
++
++static void
++error(const char *msg)
++{
++ if (depth == 0)
++ warnx("%s: %d: %s", filename, linenum, msg);
++ else
++ warnx("%s: %d: %s (#if line %d depth %d)",
++ filename, linenum, msg, stifline[depth], depth);
++ errx(2, "output may be truncated");
++}