Add pkgconfig.sysroot property

By default, pkg-config uses qbs.sysroot property which is not desirable
in some cases - for example, on macOS, even build for current system is
sysrooted to the SDK folder within XCode installation. pkg-config
installed with brew resides in /usr/local and can't be found within an
SDK dir. For that reason, it make sense to override it manually

Change-Id: Ibf779fd1bf0e87189abb2eab23d4e9e153fcca17
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

4 files changed, 49 insertions, 0 deletions

diff --git a/doc/reference/items/probe/pkgconfig-probe.qdoc b/doc/reference/items/probe/pkgconfig-probe.qdoc
index 1de84263e..7bdaf4e19 100644
--- a/doc/reference/items/probe/pkgconfig-probe.qdoc
+++ b/doc/reference/items/probe/pkgconfig-probe.qdoc
@@ -59,6 +59,20 @@
 */
 
 /*!
+    \qmlproperty string PkgConfigProbe::sysroot
+
+    This property sets the value of the \c PKG_CONFIG_SYSROOT_DIR environment variable passed to
+    the \c pkg-config binary. This variable modifies -I and -L flags to use the directories located
+    in target sysroot.
+
+    This property is useful when cross-compiling packages that use \c pkg-config to determine CFLAGS
+    and LDFLAGS. For example, if \c sysroot is set to \c /var/target, a \c -I/usr/include/libfoo
+    will become \c -I/var/target/usr/include/libfoo.
+
+    \defaultvalue \c qbs.sysroot
+*/
+
+/*!
     \qmlproperty string PkgConfigProbe::executable
 
     The name of or the path to the pkg-config executable.
@@ -125,6 +139,9 @@
     List of full, non-sysrooted paths where pkg-config should search for .pc files. This overrides
     the built-in path (which is usually /usr/lib/pkgconfig).
 
+    This property sets the value of the \c PKG_CONFIG_LIBDIR environment variable passed to
+    the \c pkg-config binary.
+
     \nodefaultvalue
 */
 
@@ -178,6 +195,9 @@
     This output property contains the list of library paths that should be passed to a linker when
     using requested package.
 
+    This property sets the value of the PKG_CONFIG_LIBDIR environment variable passed to
+    the \c pkg-config binary.
+
     \nodefaultvalue
 */
 
diff --git a/doc/reference/modules/pkgconfig-module.qdoc b/doc/reference/modules/pkgconfig-module.qdoc
index 898349628..f30308895 100644
--- a/doc/reference/modules/pkgconfig-module.qdoc
+++ b/doc/reference/modules/pkgconfig-module.qdoc
@@ -67,3 +67,26 @@
 
     \defaultvalue \c false
 */
+
+/*!
+    \qmlproperty path pkgconfig::sysroot
+
+    This property controls the value of the \l{PkgConfigProbe::sysroot}{PkgConfigProbe.sysroot}
+    property.
+
+    Set this property if you need to overwrite the default search sysroot path used by
+    \c pkg-config.
+
+    This can be useful if \c pkg-config files are located in the directory other than qbs.sysroot.
+    This is the case on macOS platform - all XCode profiles are sysrooted to the SDK
+    directory, but \c pkg-config is typically intalled using Brew and resides in the
+    \c /usr/local directory.
+
+    Setting this property to \c undefined or empty (\c "") value will use pkg-config's default
+    search paths:
+    \code
+        qbs build modules.pkgconfig.sysroot:undefined
+    \endcode
+
+    \defaultvalue \c "" on macOS, \c qbs.sysroot on other platforms
+*/
diff --git a/share/qbs/module-providers/__fallback/fallback.qbs b/share/qbs/module-providers/__fallback/fallback.qbs
index e23851951..632d1aa7a 100644
--- a/share/qbs/module-providers/__fallback/fallback.qbs
+++ b/share/qbs/module-providers/__fallback/fallback.qbs
@@ -50,6 +50,7 @@ Module {
     Probes.PkgConfigProbe {
         id: pkgConfigProbe
         condition: pkgconfig.present
+        sysroot: pkgconfig.sysroot
         name: theName
         executable: pkgconfig.executableFilePath
         libDirs: pkgconfig.libDirs
diff --git a/share/qbs/modules/pkgconfig/pkgconfig.qbs b/share/qbs/modules/pkgconfig/pkgconfig.qbs
index 92e0bfb25..ec4b59188 100644
--- a/share/qbs/modules/pkgconfig/pkgconfig.qbs
+++ b/share/qbs/modules/pkgconfig/pkgconfig.qbs
@@ -47,6 +47,11 @@ Module {
         names: "pkg-config"
     }
 
+    property path sysroot: {
+        if (qbs.targetOS.contains("macos"))
+            return "";
+        return qbs.sysroot;
+    }
     property string executableFilePath: pkgconfigProbe.filePath
     property stringList libDirs
     property bool staticMode: false