1 files changed, 23 insertions, 65 deletions
diff --git a/scripts/jobserver-exec b/scripts/jobserver-exec
index 7eca035472d3..758e947a6fb9 100755
--- a/scripts/jobserver-exec
+++ b/scripts/jobserver-exec
@@ -1,77 +1,35 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0+
-#
-# This determines how many parallel tasks "make" is expecting, as it is
-# not exposed via an special variables, reserves them all, runs a subprocess
-# with PARALLELISM environment variable set, and releases the jobs back again.
-#
-# https://www.gnu.org/software/make/manual/html_node/POSIX-Jobserver.html#POSIX-Jobserver
-from __future__ import print_function
-import os, sys, errno
-import subprocess
 
-# Extract and prepare jobserver file descriptors from environment.
-claim = 0
-jobs = b""
-try:
-	# Fetch the make environment options.
-	flags = os.environ['MAKEFLAGS']
+"""
+Determines how many parallel tasks "make" is expecting, as it is
+not exposed via any special variables, reserves them all, runs a subprocess
+with PARALLELISM environment variable set, and releases the jobs back again.
 
-	# Look for "--jobserver=R,W"
-	# Note that GNU Make has used --jobserver-fds and --jobserver-auth
-	# so this handles all of them.
-	opts = [x for x in flags.split(" ") if x.startswith("--jobserver")]
+See:
+    https://www.gnu.org/software/make/manual/html_node/POSIX-Jobserver.html#POSIX-Jobserver
+"""
 
-	# Parse out R,W file descriptor numbers and set them nonblocking.
-	# If the MAKEFLAGS variable contains multiple instances of the
-	# --jobserver-auth= option, the last one is relevant.
-	fds = opts[-1].split("=", 1)[1]
+import os
+import sys
 
-	# Starting with GNU Make 4.4, named pipes are used for reader and writer.
-	# Example argument: --jobserver-auth=fifo:/tmp/GMfifo8134
-	_, _, path = fds.partition('fifo:')
+LIB_DIR = "../tools/lib/python"
+SRC_DIR = os.path.dirname(os.path.realpath(__file__))
 
-	if path:
-		reader = os.open(path, os.O_RDONLY | os.O_NONBLOCK)
-		writer = os.open(path, os.O_WRONLY)
-	else:
-		reader, writer = [int(x) for x in fds.split(",", 1)]
-		# Open a private copy of reader to avoid setting nonblocking
-		# on an unexpecting process with the same reader fd.
-		reader = os.open("/proc/self/fd/%d" % (reader),
-				 os.O_RDONLY | os.O_NONBLOCK)
+sys.path.insert(0, os.path.join(SRC_DIR, LIB_DIR))
 
-	# Read out as many jobserver slots as possible.
-	while True:
-		try:
-			slot = os.read(reader, 8)
-			jobs += slot
-		except (OSError, IOError) as e:
-			if e.errno == errno.EWOULDBLOCK:
-				# Stop at the end of the jobserver queue.
-				break
-			# If something went wrong, give back the jobs.
-			if len(jobs):
-				os.write(writer, jobs)
-			raise e
-	# Add a bump for our caller's reserveration, since we're just going
-	# to sit here blocked on our child.
-	claim = len(jobs) + 1
-except (KeyError, IndexError, ValueError, OSError, IOError) as e:
-	# Any missing environment strings or bad fds should result in just
-	# not being parallel.
-	pass
+from jobserver import JobserverExec                  # pylint: disable=C0415
 
-# We can only claim parallelism if there was a jobserver (i.e. a top-level
-# "-jN" argument) and there were no other failures. Otherwise leave out the
-# environment variable and let the child figure out what is best.
-if claim > 0:
-	os.environ['PARALLELISM'] = '%d' % (claim)
 
-rc = subprocess.call(sys.argv[1:])
+def main():
+    """Main program"""
+    if len(sys.argv) < 2:
+        name = os.path.basename(__file__)
+        sys.exit("usage: " + name +" command [args ...]\n" + __doc__)
 
-# Return all the reserved slots.
-if len(jobs):
-	os.write(writer, jobs)
+    with JobserverExec() as jobserver:
+        jobserver.run(sys.argv[1:])
 
-sys.exit(rc)
+
+if __name__ == "__main__":
+    main()