motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-07-27 04:13:53 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fix qapi code generation wrt parallel build

Browse source 
Make's multiple output syntax

  x.c x.h: x.template
       gen < x.template

actually invokes the command once for x.c and once for x.h (with differing $@
in each invocation).  During a parallel build, the two commands may be invoked
in parallel; this opens up a race, where the second invocation trashes a file
supposedly produced during the first, and now in use by a dependent command.

The various qapi code generators are susceptible to this; fix by making them
generate just one file per invocation.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Avi Kivity 2011-12-27 16:02:16 +02:00 • committed by Anthony Liguori
parent 4e1ea514f9
commit 8d3bc5178f
4 changed files with 86 additions and 18 deletions
Download patch file Download diff file Expand all files Collapse all files

27
scripts/qapi-types.py
View file

@ -163,7 +163,8 @@ void qapi_free_%(type)s(%(c_type)s obj)
try:
opts, args = getopt.gnu_getopt(sys.argv[1:], "p:o:", ["prefix=", "output-dir="])
opts, args = getopt.gnu_getopt(sys.argv[1:], "chp:o:",
["source", "header", "prefix=", "output-dir="])
except getopt.GetoptError, err:
print str(err)
sys.exit(1)
@ -173,11 +174,22 @@ prefix = ""
c_file = 'qapi-types.c'
h_file = 'qapi-types.h'
do_c = False
do_h = False
for o, a in opts:
if o in ("-p", "--prefix"):
prefix = a
elif o in ("-o", "--output-dir"):
output_dir = a + "/"
elif o in ("-c", "--source"):
do_h = True
elif o in ("-h", "--header"):
do_c = True
if not do_c and not do_h:
do_c = True
do_h = True
c_file = output_dir + prefix + c_file
h_file = output_dir + prefix + h_file
@ -188,8 +200,17 @@ except os.error, e:
if e.errno != errno.EEXIST:
raise
fdef = open(c_file, 'w')
fdecl = open(h_file, 'w')
def maybe_open(really, name, opt):
class Null(object):
def write(self, str):
pass
def read(self):
return ''
if really:
return open(name, opt)
fdef = maybe_open(do_c, c_file, 'w')
fdecl = maybe_open(do_h, h_file, 'w')
fdef.write(mcgen('''
/* AUTOMATICALLY GENERATED, DO NOT MODIFY */