multiprocessing.eclass: Support passing custom inf values for getters

Support passing custom values for 'infinity' in makeopts_jobs()
and makeopts_loadavg(). This can be used e.g. when a build system does
not support --loadavg, and therefore '--jobs 999' would most likely
be a really bad idea. Combined with get_nproc(), this can be used to
provide a sane replacement instead.

1 files changed, 10 insertions, 7 deletions

diff --git a/eclass/multiprocessing.eclass b/eclass/multiprocessing.eclass
index 3c5dfff2d11c..70ca475a8c72 100644
--- a/eclass/multiprocessing.eclass
+++ b/eclass/multiprocessing.eclass
@@ -86,26 +86,27 @@ get_nproc() {
 }
 
 # @FUNCTION: makeopts_jobs
-# @USAGE: [${MAKEOPTS}]
+# @USAGE: [${MAKEOPTS}] [${inf:-999}]
 # @DESCRIPTION:
 # Searches the arguments (defaults to ${MAKEOPTS}) and extracts the jobs number
 # specified therein.  Useful for running non-make tools in parallel too.
 # i.e. if the user has MAKEOPTS=-j9, this will echo "9" -- we can't return the
 # number as bash normalizes it to [0, 255].  If the flags haven't specified a
 # -j flag, then "1" is shown as that is the default `make` uses.  Since there's
-# no way to represent infinity, we return 999 if the user has -j without a number.
+# no way to represent infinity, we return ${inf} (defaults to 999) if the user
+# has -j without a number.
 makeopts_jobs() {
 	[[ $# -eq 0 ]] && set -- ${MAKEOPTS}
 	# This assumes the first .* will be more greedy than the second .*
 	# since POSIX doesn't specify a non-greedy match (i.e. ".*?").
 	local jobs=$(echo " $* " | sed -r -n \
 		-e 's:.*[[:space:]](-[a-z]*j|--jobs[=[:space:]])[[:space:]]*([0-9]+).*:\2:p' \
-		-e 's:.*[[:space:]](-[a-z]*j|--jobs)[[:space:]].*:999:p')
+		-e "s:.*[[:space:]](-[a-z]*j|--jobs)[[:space:]].*:${2:-999}:p")
 	echo ${jobs:-1}
 }
 
 # @FUNCTION: makeopts_loadavg
-# @USAGE: [${MAKEOPTS}]
+# @USAGE: [${MAKEOPTS}] [${inf:-999}]
 # @DESCRIPTION:
 # Searches the arguments (defaults to ${MAKEOPTS}) and extracts the value set
 # for load-average. For make and ninja based builds this will mean new jobs are
@@ -113,15 +114,17 @@ makeopts_jobs() {
 # get excessive due to I/O and not just due to CPU load.
 # Be aware that the returned number might be a floating-point number. Test
 # whether your software supports that.
+# If no limit is specified or --load-average is used without a number, ${inf}
+# (defaults to 999) is returned.
 makeopts_loadavg() {
 	[[ $# -eq 0 ]] && set -- ${MAKEOPTS}
 	# This assumes the first .* will be more greedy than the second .*
 	# since POSIX doesn't specify a non-greedy match (i.e. ".*?").
 	local lavg=$(echo " $* " | sed -r -n \
 		-e 's:.*[[:space:]](-[a-z]*l|--(load-average|max-load)[=[:space:]])[[:space:]]*([0-9]+|[0-9]+\.[0-9]+).*:\3:p' \
-		-e 's:.*[[:space:]](-[a-z]*l|--(load-average|max-load))[[:space:]].*:999:p')
-	# Default to 999 since the default is to not use a load limit.
-	echo ${lavg:-999}
+		-e "s:.*[[:space:]](-[a-z]*l|--(load-average|max-load))[[:space:]].*:${2:-999}:p")
+	# Default to ${inf} since the default is to not use a load limit.
+	echo ${lavg:-${2:-999}}
 }
 
 # @FUNCTION: multijob_init