# HG changeset patch
# User Yuya Nishihara <yuya@tcha.org>
# Date 1413602690 -32400
# Node ID 19f5273c9f3e665bcfefdbec65f29321a08a3d23
# Parent  5f8f8225fc7e21da8bc01cdd8e9462deae5163be
cmdserver: include pid of server handling requests in hello message

Because unix-mode server forks child process per connection, client does not
know the pid of the server that will handle requests.  The pid is necessary
to interrupt hung process:

 1. client connects to socket server
 2. server accepts the connection, forks, and tells pid
 3. client requests "runcommand pull"
    .. hung ..
 4. client sends SIGINT to the (forked) server
 5. server returns from I/O wait

Note that getsockopt(SO_PEERCRED) of Linux cannot be used because the server
fork()s after accept().

diff -r 5f8f8225fc7e -r 19f5273c9f3e mercurial/commandserver.py
--- a/mercurial/commandserver.py	Sat Oct 18 21:52:11 2014 +0900
+++ b/mercurial/commandserver.py	Sat Oct 18 12:24:50 2014 +0900
@@ -232,6 +232,8 @@
         hellomsg = 'capabilities: ' + ' '.join(sorted(self.capabilities))
         hellomsg += '\n'
         hellomsg += 'encoding: ' + encoding.encoding
+        hellomsg += '\n'
+        hellomsg += 'pid: %d' % os.getpid()
 
         # write the hello msg in -one- chunk
         self.cout.write(hellomsg)
diff -r 5f8f8225fc7e -r 19f5273c9f3e tests/test-commandserver.t
--- a/tests/test-commandserver.t	Sat Oct 18 21:52:11 2014 +0900
+++ b/tests/test-commandserver.t	Sat Oct 18 12:24:50 2014 +0900
@@ -16,7 +16,7 @@
   ...     # run an arbitrary command to make sure the next thing the server
   ...     # sends isn't part of the hello message
   ...     runcommand(server, ['id'])
-  o, 'capabilities: getencoding runcommand\nencoding: *' (glob)
+  o, 'capabilities: getencoding runcommand\nencoding: *\npid: *' (glob)
   *** runcommand id
   000000000000 tip
 
@@ -531,7 +531,7 @@
   ...     # run an arbitrary command to make sure the next thing the server
   ...     # sends isn't part of the hello message
   ...     runcommand(server, ['id'])
-  o, 'capabilities: getencoding runcommand\nencoding: *' (glob)
+  o, 'capabilities: getencoding runcommand\nencoding: *\npid: *' (glob)
   *** runcommand id
   abort: there is no Mercurial repository here (.hg not found)
    [255]
@@ -562,7 +562,7 @@
   ...     print '%c, %r' % (ch, data)
   ...     runcommand(conn, ['id'])
   >>> check(hellomessage, server.connect)
-  o, 'capabilities: getencoding runcommand\nencoding: *' (glob)
+  o, 'capabilities: getencoding runcommand\nencoding: *\npid: *' (glob)
   *** runcommand id
   eff892de26ec tip bm1/bm2/bm3
   >>> def unknowncommand(conn):