1.\" Copyright (c) 1985, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" Copyright (c) 2002 - 2005 Tony Finch <dot@dotat.at>. All rights reserved. 4.\" 5.\" This code is derived from software contributed to Berkeley by 6.\" Dave Yost. It was rewritten to support ANSI C by Tony Finch. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)unifdef.1 8.2 (Berkeley) 4/1/94 33.\" $dotat: things/unifdef.1,v 1.51 2005/03/08 12:39:01 fanf2 Exp $ 34.\" $DragonFly: src/usr.bin/unifdef/unifdef.1,v 1.3 2005/07/25 17:51:36 hmp Exp $ 35.\" $FreeBSD: src/usr.bin/unifdef/unifdef.1,v 1.24 2005/05/21 09:55:09 ru Exp $ 36.\" 37.Dd September 24, 2002 38.Dt UNIFDEF 1 39.Os 40.Sh NAME 41.Nm unifdef , unifdefall 42.Nd remove preprocessor conditionals from code 43.Sh SYNOPSIS 44.Nm 45.Op Fl cdeklnst 46.Op Fl I Ns Ar path 47.Op Fl D Ns Ar sym Ns Op = Ns Ar val 48.Op Fl U Ns Ar sym 49.Op Fl iD Ns Ar sym Ns Op = Ns Ar val 50.Op Fl iU Ns Ar sym 51.Ar ... 52.Op Ar file 53.Nm unifdefall 54.Op Fl I Ns Ar path 55.Ar ... 56.Ar file 57.Sh DESCRIPTION 58The 59.Nm 60utility selectively processes conditional 61.Xr cpp 1 62directives. 63It removes from a file 64both the directives 65and any additional text that they specify should be removed, 66while otherwise leaving the file alone. 67.Pp 68The 69.Nm 70utility acts on 71.Ic #if , #ifdef , #ifndef , #elif , #else , 72and 73.Ic #endif 74lines, 75and it understands only the commonly-used subset 76of the expression syntax for 77.Ic #if 78and 79.Ic #elif 80lines. 81It handles 82integer values of symbols defined on the command line, 83the 84.Fn defined 85operator applied to symbols defined or undefined on the command line, 86the operators 87.Ic \&! , < , > , <= , >= , == , != , && , || , 88and parenthesized expressions. 89Anything that it does not understand is passed through unharmed. 90It only processes 91.Ic #ifdef 92and 93.Ic #ifndef 94directives if the symbol is specified on the command line, 95otherwise they are also passed through unchanged. 96By default, it ignores 97.Ic #if 98and 99.Ic #elif 100lines with constant expressions, 101or they may be processed by specifying the 102.Fl k 103flag on the command line. 104.Pp 105The 106.Nm 107utility also understands just enough about C 108to know when one of the directives is inactive 109because it is inside 110a comment, 111or affected by a backslash-continued line. 112It spots unusually-formatted preprocessor directives 113and knows when the layout is too odd to handle. 114.Pp 115A script called 116.Nm unifdefall 117can be used to remove all conditional 118.Xr cpp 1 119directives from a file. 120It uses 121.Nm Fl s 122and 123.Nm cpp Fl dM 124to get lists of all the controlling symbols 125and their definitions (or lack thereof), 126then invokes 127.Nm 128with appropriate arguments to process the file. 129.Pp 130Available options: 131.Pp 132.Bl -tag -width indent -compact 133.It Fl D Ns Ar sym Ns Op = Ns Ar val 134Specify that a symbol is defined, 135and optionally specify what value to give it 136for the purpose of handling 137.Ic #if 138and 139.Ic #elif 140directives. 141.Pp 142.It Fl U Ns Ar sym 143Specify that a symbol is undefined. 144If the same symbol appears in more than one argument, 145the last occurrence dominates. 146.Pp 147.It Fl c 148If the 149.Fl c 150flag is specified, 151then the operation of 152.Nm 153is complemented, 154i.e., the lines that would have been removed or blanked 155are retained and vice versa. 156.Pp 157.It Fl d 158Turn on printing of degugging messages. 159.Pp 160.It Fl e 161Because 162.Nm 163processes its input one line at a time, 164it cannot remove preprocessor directives that span more than one line. 165The most common example of this is a directive with a multi-line 166comment hanging off its right hand end. 167By default, 168if 169.Nm 170has to process such a directive, 171it will complain that the line is too obfuscated. 172The 173.Fl e 174option changes the behaviour so that, 175where possible, 176such lines are left unprocessed instead of reporting an error. 177.Pp 178.It Fl k 179Process 180.Ic #if 181and 182.Ic #elif 183lines with constant expressions. 184By default, sections controlled by such lines are passed through unchanged 185because they typically start 186.Dq Li "#if 0" 187and are used as a kind of comment to sketch out future or past development. 188It would be rude to strip them out, just as it would be for normal comments. 189.Pp 190.It Fl l 191Replace removed lines with blank lines 192instead of deleting them. 193.Pp 194.It Fl n 195Add 196.Li #line 197directives to the output following any deleted lines, 198so that errors produced when compiling the output file correspond to 199line numbers in the input file. 200.Pp 201.It Fl s 202Instead of processing the input file as usual, 203this option causes 204.Nm 205to produce a list of symbols that appear in expressions 206that 207.Nm 208understands. 209It is useful in conjunction with the 210.Fl dM 211option of 212.Xr cpp 1 213for creating 214.Nm 215command lines. 216.Pp 217.It Fl t 218Disables parsing for C comments 219and line continuations, 220which is useful 221for plain text. 222.Pp 223.It Fl iD Ns Ar sym Ns Op = Ns Ar val 224.It Fl iU Ns Ar sym 225Ignore 226.Ic #ifdef Ns s . 227If your C code uses 228.Ic #ifdef Ns s 229to delimit non-C lines, 230such as comments 231or code which is under construction, 232then you must tell 233.Nm 234which symbols are used for that purpose so that it will not try to parse 235comments 236and line continuations 237inside those 238.Ic #ifdef Ns s . 239One specifies ignored symbols with 240.Fl iD Ns Ar sym Ns Oo = Ns Ar val Oc 241and 242.Fl iU Ns Ar sym 243similar to 244.Fl D Ns Ar sym Ns Op = Ns Ar val 245and 246.Fl U Ns Ar sym 247above. 248.Pp 249.It Fl I Ns Ar path 250Specifies to 251.Nm unifdefall 252an additional place to look for 253.Ic #include 254files. 255This option is ignored by 256.Nm 257for compatibility with 258.Xr cpp 1 259and to simplify the implementation of 260.Nm unifdefall . 261.El 262.Pp 263The 264.Nm 265utility copies its output to 266.Em stdout 267and will take its input from 268.Em stdin 269if no 270.Ar file 271argument is given. 272.Pp 273The 274.Nm 275utility works nicely with the 276.Fl D Ns Ar sym 277option of 278.Xr diff 1 . 279.Sh EXIT STATUS 280The 281.Nm 282utility exits 0 if the output is an exact copy of the input, 2831 if not, and 2 if in trouble. 284.Sh DIAGNOSTICS 285.Bl -item 286.It 287Too many levels of nesting. 288.It 289Inappropriate 290.Ic #elif , 291.Ic #else 292or 293.Ic #endif . 294.It 295Obfuscated preprocessor control line. 296.It 297Premature 298.Tn EOF 299(with the line number of the most recent unterminated 300.Ic #if ) . 301.It 302.Tn EOF 303in comment. 304.El 305.Sh SEE ALSO 306.Xr cpp 1 , 307.Xr diff 1 308.Sh HISTORY 309The 310.Nm 311command appeared in 312.Bx 4.3 . 313.Tn ANSI\~C 314support was added in 315.Fx 4.7 . 316.Sh BUGS 317Expression evaluation is very limited. 318.Pp 319Preprocessor control lines split across more than one physical line 320(because of comments or backslash-newline) 321cannot be handled in every situation. 322.Pp 323Trigraphs are not recognized. 324.Pp 325There is no support for symbols with different definitions at 326different points in the source file. 327.Pp 328The text-mode and ignore functionality does not correspond to modern 329.Xr cpp 1 330behaviour. 331