From 8d3bc5178fbc06cdd89c064ae8f44e77c503e91e Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Tue, 27 Dec 2011 16:02:16 +0200 Subject: Fix qapi code generation wrt parallel build 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 Signed-off-by: Anthony Liguori --- scripts/qapi-commands.py | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) (limited to 'scripts/qapi-commands.py') diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py index 54d1f5d659..bd7b207122 100644 --- a/scripts/qapi-commands.py +++ b/scripts/qapi-commands.py @@ -372,7 +372,9 @@ def gen_command_def_prologue(prefix="", proxy=False): try: - opts, args = getopt.gnu_getopt(sys.argv[1:], "p:o:m", ["prefix=", "output-dir=", "type=", "middle"]) + opts, args = getopt.gnu_getopt(sys.argv[1:], "chp:o:m", + ["source", "header", "prefix=", + "output-dir=", "type=", "middle"]) except getopt.GetoptError, err: print str(err) sys.exit(1) @@ -384,6 +386,9 @@ c_file = 'qmp-marshal.c' h_file = 'qmp-commands.h' middle_mode = False +do_c = False +do_h = False + for o, a in opts: if o in ("-p", "--prefix"): prefix = a @@ -393,10 +398,29 @@ for o, a in opts: dispatch_type = a elif o in ("-m", "--middle"): middle_mode = True + 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 +def maybe_open(really, name, opt): + class Null(object): + def write(self, str): + pass + def read(self): + return '' + if really: + return open(name, opt) + else: + return Null() + try: os.makedirs(output_dir) except os.error, e: @@ -408,8 +432,8 @@ commands = filter(lambda expr: expr.has_key('command'), exprs) commands = filter(lambda expr: not expr.has_key('gen'), commands) if dispatch_type == "sync": - fdecl = open(h_file, 'w') - fdef = open(c_file, 'w') + fdecl = maybe_open(do_h, h_file, 'w') + fdef = maybe_open(do_c, c_file, 'w') ret = gen_command_decl_prologue(header=basename(h_file), guard=guardname(h_file), prefix=prefix) fdecl.write(ret) ret = gen_command_def_prologue(prefix=prefix) -- cgit v1.2.3