Add new logical functions for handling y/n values like those we use in CONFIG_FOO variables: lnot : logical NOT land : logical AND lor : logical OR eq : equality ne : non-equality lif : like Make's $(if) but with an eq-like test
and a couple of utility functions: isempty : true if argument is empty notempty : true if argument is not empty Based on an idea by Ákos Kovács <akoskov...@gmx.com>. Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> --- rules.mak | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/rules.mak b/rules.mak index abc2e84..ccbf0e3 100644 --- a/rules.mak +++ b/rules.mak @@ -89,6 +89,24 @@ find-in-path = $(if $(find-string /, $1), \ $(wildcard $1), \ $(wildcard $(patsubst %, %/$1, $(subst :, ,$(PATH))))) +# Logical functions (for operating on y/n values like CONFIG_FOO vars) +# Inputs to these must be either "y" (true) or "n" or "" (both false) +# Output is always either "y" or "n". +# Usage: $(call land,$(CONFIG_FOO),$(CONFIG_BAR)) +# Logical NOT +lnot = $(if $(subst n,,$1),n,y) +# Logical AND +land = $(if $(findstring yy,$1$2),y,n) +# Logical OR +lor = $(if $(findstring y,$1$2),y,n) +# Comparison: note that "n" is eq to "". +eq = $(if $(filter $(call lnot,$1),$(call lnot,$2)),y,n) +ne = $(if $(filter $(call lnot,$1),$(call lnot,$2)),n,y) + +# Returns "y" or "n" depending on whether input argument is the empty string +isempty = $(if $1,n,y) +notempty = $(if $1,y,n) + # Generate files with tracetool TRACETOOL=$(PYTHON) $(SRC_PATH)/scripts/tracetool.py -- 1.7.9.5