Add notes on libtool, by Todd Vierling <tv@netbsd.org>

1 files changed, 82 insertions, 4 deletions

diff --git a/Packages.txt b/Packages.txt
index 842f8d66ea0..fe16a507fd6 100644
--- a/Packages.txt
+++ b/Packages.txt
@@ -1,4 +1,4 @@
-# $NetBSD: Packages.txt,v 1.38 1998/07/13 15:37:12 hubertf Exp $
+# $NetBSD: Packages.txt,v 1.39 1998/07/16 06:50:46 hubertf Exp $
 ###########################################################################
 
 			==========================
@@ -644,7 +644,84 @@ You should also avoid defining __FreeBSD__=1 and then simply using the
 FreeBSD port, if only from an aesthetic viewpoint.
 
 
- 6.2 Gotchas of FreeBSD ports
+ 6.2 Shared libraries - libtool
+ ==============================
+
+NetBSD supports many different machines, with different object formats
+like a.out and ELF, and varying abilities to do shared library and
+dynamic loading at all. To accompany this, verying commands and options
+have to be passed to the compiler, linker etc. to get the Right Thing,
+which can be pretty annoying esp. if you don't have all the machines at
+your hand to test things. The "libtool" pkg can help here, as it just
+"knows" how to build both static and dynamic libraries from a set our
+source files, thus being platform independent. 
+
+To use "libtool", add a build-dependency on the libtool-pkg, then modify
+the pkg's sources to use libtool for building it's libraries and add the
+resulting patches to your pkg's patches-directory. 
+
+Here's how to use libtool in a pkg in seven simple steps:
+
+1. Define LIBTOOL=${PREFIX}/bin/libtool in MAKE_ENV, or define it in a
+   patch to the native Makefile.  Make the pkg depend on libtool with:
+
+	BUILD_DEPENDS= ${PREFIX}/bin/libtool:../../devel/libtool
+
+2. For library objects, use "${LIBTOOL} --mode=compile ${CC}" in place of
+   ${CC}.  You could even add it to the definition of CC, if only
+   libraries are being built in a given Makefile.  This one command will
+   build both PIC and non-PIC library objects, so you need not have
+   separate shared and non-shared library rules.
+
+3. For the linking of the library, remove any "ar", "ranlib", and "ld
+   -Bshareable" commands, and use instead:
+
+	${LIBTOOL} --mode=link cc -o ${.TARGET:.a=.la} ${OBJS:.o=.lo} -rpath ${PREFIX}/lib -version-info major:minor
+
+   Note that the library is changed to have a .la extension, and the
+   objects are changed to have a .lo extension.  Change OBJS as necessary.
+   This automatically creates all of the .a, .so.major.minor, and ELF
+   symlinks (if necessary) in the build directory.
+
+4. When linking programs that depend on these libraries _before_ they are
+   installed, preface the cc or ld line with "${LIBTOOL} --mode=link", and
+   it will find the correct libraries (static or shared), but please be
+   aware that libtool will not allow you to specify a relative path in -L
+   (such as -L../somelib), because it is trying to force you to change
+   that argument to be the .la file.  For example:
+
+	${LIBTOOL} --mode=link ${CC} -o someprog -L../somelib -lsomelib
+
+   won't work; it needs to be changed to:
+
+	${LIBTOOL} --mode=link ${CC} -o someprog ../somelib/somelib.la
+
+   and it will DTRT with the libraries.  If you *must* use a relative path 
+   with -L, and you are not going to run this program before installing
+   it, you can omit the use of libtool during link and install of this
+   program if you add the subdirectory ".libs" in your -L command:
+
+	${CC} -o someprog -L../somelib/.libs -lsomelib
+
+5. When installing libraries, preface the install or cp command with
+   "${LIBTOOL} --mode=install", and change the library name to .la.  For
+   example:
+
+	${LIBTOOL} --mode=install ${BSD_INSTALL_DATA} ${SOMELIB:.a=.la} ${PREFIX}/lib
+
+   This will install the static .a, shared library, any needed symlinks,
+   and run "ldconfig."
+
+6. In your PLIST, include the .a, .la, and .so.major.minor files.  Don't
+   include the ELF symlink files; those are automatic. 
+
+FOR GNU PKGS THAT ALREADY SUPPORT LIBTOOL: 
+Put LIBTOOL=${PREFIX}/bin/libtool in CONFIGURE_ENV, and possibly modify the
+"configure" script not to check for or configure its own libtool.  See the
+libwww pkg, patch-ab, for the quick way to bypass the pkg's own libtool.
+
+
+ 6.3 Gotchas of FreeBSD ports
  ============================
 
 See section 4.1 for Makefile issues (MANx, CATx, MANCOMPRESSED, ldconfig,
@@ -672,7 +749,7 @@ manpages without compressing them; rather, we add our own .gz suffix there
 according to MANZ.
 
 
- 6.3 Feedback to the author
+ 6.4 Feedback to the author
  ==========================
 
 If you have found any bugs in the package you make available, if you had to
@@ -1266,7 +1343,8 @@ Now compile:
 > cc -c -DSTDC_HEADERS=1 -DHAVE_STRING_H=1 -DHAVE_STDLIB_H=1 -DHAVE_MEMORY_H=1 -DHAVE_ALLOCA=1 -DHAVE_STRERROR=1 -I./../include  -g version.c
 > cc -c -DSTDC_HEADERS=1 -DHAVE_STRING_H=1 -DHAVE_STDLIB_H=1 -DHAVE_MEMORY_H=1 -DHAVE_ALLOCA=1 -DHAVE_STRERROR=1 -I./../include  -g getopt.c
 > cc -c -DSTDC_HEADERS=1 -DHAVE_STRING_H=1 -DHAVE_STDLIB_H=1 -DHAVE_MEMORY_H=1 -DHAVE_ALLOCA=1 -DHAVE_STRERROR=1 -I./../include  -g getopt1.c
-> cc  -g -o bison LR0.o allocate.o closure.o conflicts.o derives.o files.o         getargs.o gram.o lalr.o lex.o                                   main.o nullable.o output.o print.o reader.o reduce.o symtab.o   warshall.o version.o                                            getopt.o getopt1.o  
+> cc  -g -o bison LR0.o allocate.o closure.o conflicts.o derives.o files.o         getargs.o gram.o lalr.o lex.o                                   main.o nullable.o output.o print.o reader.o reduce.o symtab.o   warshall.o version.o                        
+                    getopt.o getopt1.o  
 > ./files.c:240: warning: mktemp() possibly used unsafely, consider using mkstemp()
 > rm -f bison.s1
 > sed -e "/^#line/ s|bison|/usr/pkg/share/bison|" < ./bison.simple > bison.s1