docs/69086: Porters Handbook: How to convert from CR/LF to LF using REINPLACE_CMD

[Alexey Dokuchaev]

>Number:         69086
>Category:       docs
>Synopsis:       Porters Handbook: How to convert from CR/LF to LF using REINPLACE_CMD
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-doc
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jul 15 07:00:44 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Alexey Dokuchaev
>Release:        FreeBSD 4.9-STABLE i386
>Organization:
CNIT NSU
>Environment:
System: FreeBSD regency.nsu.ru 4.9-STABLE FreeBSD 4.9-STABLE #1: Wed Mar 3 13:17:54 NOVT 2004 root at regency.nsu.ru:/usr/src/sys/compile/REGENCY i386
>Description:
Quite often, we have to port sotfware written for or under Windows/DOS,
which use dumb CR/LF convention for text files instead of Unix plain LF.
This often causes problems with further patching, compiler warning,
scipts execution (/bin/sh^M not found), etc.

Since there's no standard practice of dealing with such situations,
people often come up with all sorts of solutions, i.e. supplying
explicit patches in files/, adding dependency(!!!) on dos2unix, of
wrapping tr -d '\r' in a script and calling it instead of sed(1) in my
proposal, which is simple and straightforward.

I therefore suggest including this in Porter's Handbook, as in attached
patch.
>How-To-Repeat:
Try porting some fairly complex CR/LF code.
>Fix:

Index: book.sgml
===================================================================
RCS file: /home/pub/ftp/pub/FreeBSD/development/FreeBSD-CVS//doc/en_US.ISO8859-1/books/porters-handbook/book.sgml,v
retrieving revision 1.461
diff -u -r1.461 book.sgml
--- book.sgml	12 Jul 2004 08:24:15 -0000	1.461
+++ book.sgml	15 Jul 2004 06:55:26 -0000
@@ -681,6 +681,24 @@
 	  lines!); define <literal>USE_AUTOCONF_VER=213</literal> and take the
 	  diffs of <filename>configure.in</filename>.</para>
 
+	<para>Quite often, there is a situation when ported software, being
+	  primarily developed on Windows, uses CR/LF convention for most of its
+	  source files.  This may cause problems with further patching, compiler
+	  warnings, scipts execution (<command>/bin/sh^M</command> not found),
+	  etc.  To quickly convert those files from CR/LF to just LF, you can do
+	  something like this:</para>
+
+	<programlisting>USE_REINPLACE=	yes
+
+post-extract:
+	@${FIND} -E ${WRKDIR} -type f -iregex ".*\.(c|cpp|h|txt)" \
+		-exec ${REINPLACE_CMD} -e 's/[[:cntrl:]]*$$//' '{}' \;</programlisting>
+
+	<para>Of course, if you need to process each and every file,
+	  <option>-iregex</option> above can be omitted.  Be aware that this
+	  piece of code will strip all trailing control characters from each
+	  line of processed file (except <literal>\n</literal>).</para>
+
 	<para>Also, if you had to delete a file, then you can do it in the
 	  <maketarget>post-extract</maketarget> target rather than as part of
 	  the patch.  Once you are happy with the resulting diff, please split

>Release-Note:
>Audit-Trail:
>Unformatted: