c284e87d6b
* The partial-evaluation of #elif sequences was broken and the spaghetti logic of its implementation was too hard to understand. I've re-done it using a straight-forward table-driven push-down automaton. * The pre-processor line parser did not allow for all of the weird places that people might put comments, which could have caused it to add syntax-errors to the output by removing a #if line containing the start- or end-marker of a comment. * The lexer didn't need to special-case the handling of string-literals or character-constants, but it did need to learn about line-continuations (backslash-newline). * The input routine was buggy and bit-rotten and trivially replacable with fgets(). I've also made the program static- and const-safe and improved the presentation-order. The formatting of the state-transition tables remains non-stylish. This commit-messsage was brought to you by code-point 45. MFC-after: one-week
877 lines
24 KiB
C
877 lines
24 KiB
C
/*
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* Copyright (c) 1985, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Dave Yost. Support for #if and #elif was added by Tony Finch.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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#ifndef lint
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static const char copyright[] =
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"@(#) Copyright (c) 1985, 1993\n\
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The Regents of the University of California. All rights reserved.\n";
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#ifdef __IDSTRING
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__IDSTRING(Berkeley, "@(#)unifdef.c 8.1 (Berkeley) 6/6/93");
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__IDSTRING(NetBSD, "$NetBSD: unifdef.c,v 1.8 2000/07/03 02:51:36 matt Exp $");
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__IDSTRING(dotat, "$dotat: things/unifdef.c,v 1.130 2002/12/13 15:26:41 fanf2 Exp $");
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#endif
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#ifdef __FBSDID
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__FBSDID("$FreeBSD$");
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#endif
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#endif
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/*
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* unifdef - remove ifdef'ed lines
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*
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* Wishlist:
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* provide an option which will append the name of the
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* appropriate symbol after #else's and #endif's
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* provide an option which will check symbols after
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* #else's and #endif's to see that they match their
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* corresponding #ifdef or #ifndef
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* generate #line directives in place of deleted code
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*/
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#include <ctype.h>
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#include <err.h>
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#include <stdarg.h>
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#include <stdbool.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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/* types of input lines: */
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typedef enum {
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LT_PLAIN, /* ordinary line */
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LT_TRUEI, /* a true #if with ignore flag */
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LT_FALSEI, /* a false #if with ignore flag */
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LT_IF, /* an unknown #if */
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LT_TRUE, /* a true #if */
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LT_FALSE, /* a false #if */
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LT_ELIF, /* an unknown #elif */
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LT_ELTRUE, /* a true #elif */
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LT_ELFALSE, /* a false #elif */
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LT_ELSE, /* #else */
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LT_ENDIF, /* #endif */
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LT_EOF, /* end of file */
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LT_COUNT
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} Linetype;
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static char const * const linetype_name[] = {
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"PLAIN", "TRUEI", "FALSEI", "IF", "TRUE", "FALSE",
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"ELIF", "ELTRUE", "ELFALSE", "ELSE", "ENDIF", "EOF"
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};
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/* state of #if processing */
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typedef enum {
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IS_OUTSIDE,
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IS_FALSE_PREFIX, /* false #if followed by false #elifs */
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IS_TRUE_PREFIX, /* first non-false #(el)if is true */
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IS_PASS_MIDDLE, /* first non-false #(el)if is unknown */
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IS_FALSE_MIDDLE, /* a false #elif after a pass state */
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IS_TRUE_MIDDLE, /* a true #elif after a pass state */
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IS_PASS_ELSE, /* an else after a pass state */
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IS_FALSE_ELSE, /* an else after a true state */
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IS_TRUE_ELSE, /* an else after only false states */
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IS_FALSE_TRAILER, /* #elifs after a true are false */
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IS_COUNT
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} Ifstate;
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static char const * const ifstate_name[] = {
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"OUTSIDE", "FALSE_PREFIX", "TRUE_PREFIX",
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"PASS_MIDDLE", "FALSE_MIDDLE", "TRUE_MIDDLE",
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"PASS_ELSE", "FALSE_ELSE", "TRUE_ELSE",
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"FALSE_TRAILER"
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};
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/* state of comment parser */
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typedef enum {
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NO_COMMENT = false, /* outside a comment */
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C_COMMENT, /* in a comment like this one */
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CXX_COMMENT, /* between // and end of line */
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STARTING_COMMENT, /* just after slash-backslash-newline */
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FINISHING_COMMENT /* star-backslash-newline in a C comment */
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} Comment_state;
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static char const * const comment_name[] = {
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"NO", "C", "CXX", "STARTING", "FINISHING"
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};
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/* state of preprocessor line parser */
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typedef enum {
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LS_START, /* only space and comments on this line */
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LS_HASH, /* only space, comments, and a hash */
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LS_DIRTY /* this line can't be a preprocessor line */
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} Line_state;
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static char const * const linestate_name[] = {
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"START", "HASH", "DIRTY"
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};
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/*
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* Minimum translation limits from ISO/IEC 9899:1999 5.2.4.1
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*/
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#define MAXDEPTH 64 /* maximum #if nesting */
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#define MAXLINE 4096 /* maximum length of line */
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#define MAXSYMS 4096 /* maximum number of symbols */
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/*
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* Globals.
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*/
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static bool complement; /* -c: do the complement */
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static bool debugging; /* -d: debugging reports */
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static bool killconsts; /* -k: eval constant #ifs */
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static bool lnblank; /* -l: blank deleted lines */
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static bool symlist; /* -s: output symbol list */
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static bool text; /* -t: this is a text file */
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static const char *symname[MAXSYMS]; /* symbol name */
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static const char *value[MAXSYMS]; /* -Dsym=value */
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static bool ignore[MAXSYMS]; /* -iDsym or -iUsym */
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static int nsyms; /* number of symbols */
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static FILE *input; /* input file pointer */
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static const char *filename; /* input file name */
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static int linenum; /* current line number */
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static char tline[MAXLINE+10]; /* input buffer plus space */
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static char *keyword; /* used for editing #elif's */
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static Comment_state incomment; /* comment parser state */
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static Line_state linestate; /* #if line parser state */
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static Ifstate ifstate[MAXDEPTH]; /* #if processor state */
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static bool ignoring[MAXDEPTH]; /* ignore comments state */
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static int stifline[MAXDEPTH]; /* start of current #if */
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static int depth; /* current #if nesting */
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static bool keepthis; /* don't delete constant #if */
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static int exitstat; /* program exit status */
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static void addsym(bool, bool, char *);
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static void debug(const char *, ...);
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static void error(const char *);
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static int findsym(const char *);
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static void flushline(bool);
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static Linetype getline(void);
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static Linetype ifeval(const char **);
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static void nest(void);
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static void process(void);
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static const char *skipcomment(const char *);
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static const char *skipsym(const char *);
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static void state(Ifstate);
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static int strlcmp(const char *, const char *, size_t);
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static void unignore(void);
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static void usage(void);
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#define endsym(c) (!isalpha((unsigned char)c) && !isdigit((unsigned char)c) && c != '_')
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/*
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* The main program.
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*/
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int
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main(int argc, char *argv[])
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{
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int opt;
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while ((opt = getopt(argc, argv, "i:D:U:I:cdklst")) != -1)
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switch (opt) {
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case 'i': /* treat stuff controlled by these symbols as text */
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/*
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* For strict backwards-compatibility the U or D
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* should be immediately after the -i but it doesn't
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* matter much if we relax that requirement.
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*/
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opt = *optarg++;
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if (opt == 'D')
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addsym(true, true, optarg);
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else if (opt == 'U')
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addsym(true, false, optarg);
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else
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usage();
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break;
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case 'D': /* define a symbol */
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addsym(false, true, optarg);
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break;
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case 'U': /* undef a symbol */
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addsym(false, false, optarg);
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break;
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case 'I':
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/* no-op for compatibility with cpp */
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break;
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case 'c': /* treat -D as -U and vice versa */
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complement = true;
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break;
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case 'd':
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debugging = true;
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break;
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case 'k': /* process constant #ifs */
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killconsts = true;
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break;
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case 'l': /* blank deleted lines instead of omitting them */
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lnblank = true;
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break;
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case 's': /* only output list of symbols that control #ifs */
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symlist = true;
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break;
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case 't': /* don't parse C comments */
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text = true;
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break;
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default:
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usage();
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}
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argc -= optind;
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argv += optind;
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if (nsyms == 0 && !symlist) {
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warnx("must -D or -U at least one symbol");
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usage();
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}
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if (argc > 1) {
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errx(2, "can only do one file");
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} else if (argc == 1 && strcmp(*argv, "-") != 0) {
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filename = *argv;
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if ((input = fopen(filename, "r")) != NULL) {
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process();
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(void) fclose(input);
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} else
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err(2, "can't open %s", *argv);
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} else {
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filename = "[stdin]";
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input = stdin;
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process();
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}
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exit(exitstat);
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}
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static void
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usage(void)
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{
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fprintf (stderr, "usage: %s",
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"unifdef [-cdklst] [[-Dsym[=val]] [-Usym] [-iDsym[=val]] [-iUsym]] ... [file]\n");
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exit (2);
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}
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/*
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* A state transition function alters the global #if processing state
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* in a particular way. The table below is indexed by the current
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* processing state and the type of the current line. A NULL entry
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* indicate that processing is complete.
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*
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* Nesting is handled by keeping a stack of states; some transition
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* functions increase or decrease the depth. They also maintin the
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* ignore state on a stack. In some complicated cases they have to
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* alter the preprocessor directive, as follows.
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*
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* When we have processed a group that starts off with a known-false
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* #if/#elif sequence (which has therefore been deleted) followed by a
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* #elif that we don't understand and therefore must keep, we turn the
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* latter into a #if to keep the nesting correct.
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*
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* When we find a true #elif in a group, the following block will
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* always be kept and the rest of the sequence after the next #elif or
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* #else will be discarded. We change the #elif to #else and the
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* following directive to #endif since this has the desired behaviour.
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*/
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typedef void state_fn(void);
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/* report an error */
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static void Eelif (void) { error("Inappropriate #elif"); }
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static void Eelse (void) { error("Inappropriate #else"); }
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static void Eendif(void) { error("Inappropriate #endif"); }
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static void Eeof (void) { error("Premature EOF"); }
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static void Eioccc(void) { error("Obfuscated preprocessor control line"); }
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/* plain line handling */
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static void print (void) { flushline(true); }
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static void drop (void) { flushline(false); }
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/* output lacks group's start line */
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static void Strue (void) { drop(); unignore(); state(IS_TRUE_PREFIX); }
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static void Sfalse(void) { drop(); unignore(); state(IS_FALSE_PREFIX); }
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static void Selse (void) { drop(); state(IS_TRUE_ELSE); }
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/* print/pass this block */
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static void Pelif (void) { print(); unignore(); state(IS_PASS_MIDDLE); }
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static void Pelse (void) { print(); state(IS_PASS_ELSE); }
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static void Pendif(void) { print(); --depth; }
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/* discard this block */
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static void Dfalse(void) { drop(); unignore(); state(IS_FALSE_TRAILER); }
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static void Delif (void) { drop(); unignore(); state(IS_FALSE_MIDDLE); }
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static void Delse (void) { drop(); state(IS_FALSE_ELSE); }
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static void Dendif(void) { drop(); --depth; }
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/* first line of group */
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static void Fdrop (void) { nest(); Dfalse(); }
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static void Fpass (void) { nest(); Pelif(); }
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static void Ftrue (void) { nest(); Strue(); }
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static void Ffalse(void) { nest(); Sfalse(); }
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/* ignore comments in this block */
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static void Idrop (void) { Fdrop(); ignore[depth] = true; }
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static void Itrue (void) { Ftrue(); ignore[depth] = true; }
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static void Ifalse(void) { Ffalse(); ignore[depth] = true; }
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/* modify this line */
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static void
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Mpass (void) { strncpy(keyword, "if ", 4); Pelif(); }
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static void
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Mtrue (void) { strcpy(keyword, "else\n"); print(); state(IS_TRUE_MIDDLE); }
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static void
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Melif (void) { strcpy(keyword, "endif\n"); print(); state(IS_FALSE_TRAILER); }
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static void
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Melse (void) { strcpy(keyword, "endif\n"); print(); state(IS_FALSE_ELSE); }
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static state_fn * const trans_table[IS_COUNT][LT_COUNT] = {
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/* IS_OUTSIDE */
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{print,Itrue,Ifalse,Fpass,Ftrue,Ffalse,Eelif, Eelif, Eelif, Eelse,Eendif,NULL},
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/* IS_FALSE_PREFIX */
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{drop, Idrop,Idrop, Fdrop,Fdrop,Fdrop, Mpass, Strue, Sfalse,Selse,Dendif,Eeof},
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/* IS_TRUE_PREFIX */
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{print,Itrue,Ifalse,Fpass,Ftrue,Ffalse,Dfalse,Dfalse,Dfalse,Delse,Dendif,Eeof},
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/* IS_PASS_MIDDLE */
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{print,Itrue,Ifalse,Fpass,Ftrue,Ffalse,Pelif, Mtrue, Delif, Pelse,Pendif,Eeof},
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/* IS_FALSE_MIDDLE */
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{drop, Idrop,Idrop, Fdrop,Fdrop,Fdrop, Pelif, Mtrue, Delif, Pelse,Pendif,Eeof},
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/* IS_TRUE_MIDDLE */
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{print,Itrue,Ifalse,Fpass,Ftrue,Ffalse,Melif, Melif, Melif, Melse,Pendif,Eeof},
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/* IS_PASS_ELSE */
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{print,Itrue,Ifalse,Fpass,Ftrue,Ffalse,Eelif, Eelif, Eelif, Eelse,Pendif,Eeof},
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/* IS_FALSE_ELSE */
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{drop, Idrop,Idrop, Fdrop,Fdrop,Fdrop, Eelif, Eelif, Eelif, Eelse,Dendif,Eeof},
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/* IS_TRUE_ELSE */
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{print,Itrue,Ifalse,Fpass,Ftrue,Ffalse,Eelif, Eelif, Eelif, Eelse,Dendif,Eeof},
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/* IS_FALSE_TRAILER */
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{drop, Idrop,Idrop, Fdrop,Fdrop,Fdrop, Dfalse,Dfalse,Dfalse,Delse,Dendif,Eeof}
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/*PLAIN TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF EOF*/
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};
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/*
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* State machine utility functions
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*/
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static void
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nest(void)
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{
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depth += 1;
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if (depth >= MAXDEPTH)
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error("Too many levels of nesting");
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stifline[depth] = linenum;
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}
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static void
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state(Ifstate is)
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{
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ifstate[depth] = is;
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}
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static void
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unignore(void)
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{
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ignore[depth] = ignore[depth-1];
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}
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/*
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* Write a line to the output or not, according to command line options.
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*/
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static void
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flushline(bool keep)
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{
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if (symlist)
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return;
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if (keep ^ complement)
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fputs(tline, stdout);
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else {
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if (lnblank)
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putc('\n', stdout);
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exitstat = 1;
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}
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}
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/*
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* The driver for the state machine.
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*/
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static void
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process(void)
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{
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Linetype lineval;
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state_fn *trans;
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for (;;) {
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linenum++;
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lineval = getline();
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trans = trans_table[ifstate[depth]][lineval];
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if (trans == NULL)
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break;
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trans();
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debug("process %s -> %s depth %d",
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linetype_name[lineval],
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ifstate_name[ifstate[depth]], depth);
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}
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if (incomment)
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error("EOF in comment");
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}
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/*
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* Parse a line and determine its type. We keep the preprocessor line
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* parser state between calls in a global variable.
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*/
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static Linetype
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getline(void)
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{
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const char *cp;
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int cursym;
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int kwlen;
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Linetype retval;
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Comment_state wascomment;
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if (fgets(tline, MAXLINE, input) == NULL)
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return LT_EOF;
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retval = LT_PLAIN;
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wascomment = incomment;
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cp = skipcomment(tline);
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if (linestate == LS_START) {
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if (*cp == '#') {
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linestate = LS_HASH;
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cp = skipcomment(cp + 1);
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} else if (*cp != '\0')
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linestate = LS_DIRTY;
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}
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if (!incomment && linestate == LS_HASH) {
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keyword = tline + (cp - tline);
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cp = skipsym(cp);
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kwlen = cp - keyword;
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if (strncmp(cp, "\\\n", 2) == 0)
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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))
|
|
Eioccc();
|
|
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 operators that are supported by the expression evaluator.
|
|
*/
|
|
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 && !symlist)
|
|
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 && !symlist)
|
|
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
|
|
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);
|
|
return keepthis ? LT_IF : ret;
|
|
}
|
|
|
|
/*
|
|
* Skip over comments and stop at the next character position that is
|
|
* not whitespace. Between calls we keep the comment state in a global
|
|
* variable, and we also make a note when we get a proper end-of-line.
|
|
* XXX: doesn't cope with the buffer splitting inside a state transition.
|
|
*/
|
|
static const char *
|
|
skipcomment(const char *cp)
|
|
{
|
|
if (text || ignoring[depth]) {
|
|
while (isspace((unsigned char)*cp))
|
|
cp += 1;
|
|
return cp;
|
|
}
|
|
while (*cp != '\0')
|
|
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, "\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 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:
|
|
/* bug */
|
|
abort();
|
|
}
|
|
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", cp-str, str);
|
|
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)
|
|
errx(2, "%s: %d: %s", filename, linenum, msg);
|
|
else
|
|
errx(2, "%s: %d: %s (#if line %d depth %d)",
|
|
filename, linenum, msg, stifline[depth], depth);
|
|
}
|