[Buildroot] [PATCH 15/21 RFC] core/pkg-generic: add macro to hardlink-or-copy

[Yann E. MORIN]

Signed-off-by: "Yann E. MORIN" <yann.morin.1998 at free.fr>
Cc: Luca Ceresoli <luca at lucaceresoli.net>
---
 package/pkg-generic.mk | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
index 544ae5c..82fbeb0 100644
--- a/package/pkg-generic.mk
+++ b/package/pkg-generic.mk
@@ -305,6 +305,24 @@ endif
 endef
 
 ################################################################################
+# hardlink-copy -- hardlink source and destination if possible, otherwise
+# do a simple copy
+#
+# argument 1 is the source
+# argument 2 is the destination *directory*
+#
+# example:
+#   $(call hard-link-copy,source,destination)
+#
+# Note: we make that a single command, so se can:
+#  - use '$(Q)' in front of it and properly silence the whole macro,
+#  - use '|| exit 1' after it, so we can exit on error in compound commands.
+################################################################################
+define hardlink-copy
+	{ mkdir -p $(2) && { cp -l $(1) $(2) 2>/dev/null || cp $(1) $(2); } }
+endef
+
+################################################################################
 # inner-generic-package -- generates the make targets needed to build a
 # generic package
 #
-- 
1.9.1