From 6ae9bb615f7a28b3742b18e4e79bb3d1711e3bd3 Mon Sep 17 00:00:00 2001
From: Ralf Habacker <ralf.habacker@freenet.de>
Date: Wed, 15 Feb 2017 16:02:32 +0100
Subject: [PATCH 1/2] build: Optionally create relocatable dbus-1.pc file

Relocatable pkgconfig files are necessary when using packages installed to
a location that does not match the location for which they were compiled.

However, using ${pcfiledir} is problematic for system installations
in standard locations, because it interferes with pkg-config's
ability to filter out -I, -L options that are redundant with compiler
defaults (which is important if you are trying to use a newer version
of a library than the system copy). So make relocation optional, and
switch it off by default when using Autotools (as distribution vendors
do in practice) and compiling for a Unix platform.

For simplicity, we're also not relocatable if libdir (autotools)
or CMAKE_INSTALL_LIBDIR (cmake) is something more complicated
(e.g. Debian multiarch); we don't want to have to compute
how many ../ to add.

[smcv: don't be relocatable by default on Unix + Autotools]

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=99721
---
 cmake/CMakeLists.txt | 32 +++++++++++++++++++++++++-------
 configure.ac         | 19 +++++++++++++++++++
 dbus-1.pc.in         |  2 +-
 3 files changed, 45 insertions(+), 8 deletions(-)

diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index 5eb9ed3a..b484e96e 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -84,6 +84,17 @@ set(SYSCONFDIR_FROM_PKGDATADIR ${CMAKE_INSTALL_FULL_SYSCONFDIR})
 set(DATADIR_FROM_PKGSYSCONFDIR ${CMAKE_INSTALL_FULL_DATADIR})
 endif()
 
+# For simplicity, we're not relocatable if CMAKE_INSTALL_LIBDIR
+# is something more complicated (e.g. Debian multiarch);
+# we don't want to have to compute how many ../ to add
+if(CMAKE_INSTALL_LIBDIR STREQUAL "lib" OR CMAKE_INSTALL_LIBDIR STREQUAL "lib64")
+    # we know we can use ../ to get to the prefix
+    set(DBUS_RELOCATABLE 1)
+else()
+    # sorry, it's too hard to make this particular build relocatable
+    set(DBUS_RELOCATABLE 0)
+endif()
+
 # used in the C code
 set(DBUS_LIBEXECDIR          ${CMAKE_INSTALL_FULL_LIBEXECDIR})
 set(DBUS_DATADIR             ${CMAKE_INSTALL_FULL_DATADIR})
@@ -638,13 +649,20 @@ if(UNIX)
         foreach(LIB ${CMAKE_C_IMPLICIT_LINK_LIBRARIES} ${PLATFORM_LIBS})
             set(LIBDBUS_LIBS "${LIBDBUS_LIBS} -l${LIB}")
         endforeach()
-        set(bindir ${EXPANDED_BINDIR})
-        set(libdir ${EXPANDED_LIBDIR})
-        set(includedir ${EXPANDED_INCLUDEDIR})
-        set(sysconfdir ${EXPANDED_SYSCONFDIR})
-        set(datadir ${EXPANDED_DATADIR})
-        set(datarootdir ${EXPANDED_DATADIR})
-        set(dbus_daemondir ${DBUS_DAEMONDIR})
+        if(DBUS_RELOCATABLE)
+            set(pkgconfig_prefix "\${pcfiledir}/../../")
+        else()
+            message("Unusual CMAKE_INSTALL_PREFIX: the generated package will not be relocatable.")
+            set(pkgconfig_prefix "${CMAKE_INSTALL_PREFIX}")
+        endif()
+        set(exec_prefix "\${prefix}")
+        set(bindir "\${prefix}/${CMAKE_INSTALL_BINDIR}")
+        set(libdir "\${prefix}/${CMAKE_INSTALL_LIBDIR}")
+        set(includedir "\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}")
+        set(sysconfdir "\${prefix}/${CMAKE_INSTALL_SYSCONFDIR}")
+        set(datadir "\${prefix}/${CMAKE_INSTALL_DATADIR}")
+        set(datarootdir "\${prefix}/${CMAKE_INSTALL_DATADIR}")
+        set(dbus_daemondir "\${prefix}/${CMAKE_INSTALL_BINDIR}")
         configure_file(../dbus-1.pc.in ${CMAKE_BINARY_DIR}/dbus-1.pc @ONLY)
         install(FILES ${CMAKE_BINARY_DIR}/dbus-1.pc DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
     endif()
diff --git a/configure.ac b/configure.ac
index 00c271cb..c3a8c85e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1530,6 +1530,25 @@ AS_AC_EXPAND(EXPANDED_LIBDIR, "$libdir")
 AS_AC_EXPAND(EXPANDED_LIBEXECDIR, "$libexecdir")
 AS_AC_EXPAND(EXPANDED_DATADIR, "$datadir")
 
+AC_ARG_ENABLE([relocation],
+  [AS_HELP_STRING([--enable-relocation],
+    [make pkg-config metadata relocatable [default: only on Windows]])],
+  [], [enable_relocation="$dbus_win"])
+
+AS_IF([test "x$enable_relocation" = xyes],
+  [
+    AS_IF([test "x$EXPANDED_LIBDIR" = "x$EXPANDED_PREFIX/lib" ||
+      test "x$EXPANDED_LIBDIR" = "x$EXPANDED_PREFIX/lib64"],
+      [],
+      [AC_MSG_ERROR([Your libdir is too complicated to be relocatable, use \${prefix}/lib instead])])
+
+    pkgconfig_prefix='${pcfiledir}/../..'
+  ],
+  [
+    pkgconfig_prefix='${prefix}'
+  ])
+AC_SUBST([pkgconfig_prefix])
+
 #### Check our operating system
 operating_system=unknown
 if test -f /etc/redhat-release || test -f $EXPANDED_SYSCONFDIR/redhat-release ; then
diff --git a/dbus-1.pc.in b/dbus-1.pc.in
index f93d1563..26fc9709 100644
--- a/dbus-1.pc.in
+++ b/dbus-1.pc.in
@@ -1,4 +1,4 @@
-prefix=@prefix@
+prefix=@pkgconfig_prefix@
 exec_prefix=@exec_prefix@
 bindir=@bindir@
 libdir=@libdir@
-- 
2.11.0