Don't wait for the initscripts to complete.
[util-vserver.git] / python / vserver.py
index 1c85a94..de8c164 100644 (file)
@@ -1,5 +1,7 @@
 # Copyright 2005 Princeton University
 
+#$Id: vserver.py,v 1.72 2007/08/02 16:01:59 dhozac Exp $
+
 import errno
 import fcntl
 import os
@@ -9,17 +11,19 @@ import signal
 import sys
 import time
 import traceback
+import subprocess
+import resource
 
-import mountimpl
-import runcmd
-import utmp
-import vserverimpl, vduimpl
+import vserverimpl
 import cpulimit, bwlimit
 
 from vserverimpl import VS_SCHED_CPU_GUARANTEED as SCHED_CPU_GUARANTEED
 from vserverimpl import DLIMIT_INF
-
-
+from vserverimpl import VC_LIM_KEEP
+from vserverimpl import VLIMIT_NSOCK
+from vserverimpl import VLIMIT_OPENFD
+from vserverimpl import VLIMIT_ANON
+from vserverimpl import VLIMIT_SHMEM
 
 #
 # these are the flags taken from the kernel linux/vserver/legacy.h
@@ -33,85 +37,215 @@ FLAGS_HIDEINFO = 32
 FLAGS_ULIMIT = 64
 FLAGS_NAMESPACE = 128
 
-
+RLIMITS = { "NSOCK": VLIMIT_NSOCK,
+            "OPENFD": VLIMIT_OPENFD,
+            "ANON": VLIMIT_ANON,
+            "SHMEM": VLIMIT_SHMEM}
+
+# add in the platform supported rlimits
+for entry in resource.__dict__.keys():
+    if entry.find("RLIMIT_")==0:
+        k = entry[len("RLIMIT_"):]
+        if not RLIMITS.has_key(k):
+            RLIMITS[k]=resource.__dict__[entry]
+        else:
+            print "WARNING: duplicate RLIMITS key %s" % k
 
 class NoSuchVServer(Exception): pass
 
 
+class VServerConfig:
+    def __init__(self, name, directory):
+        self.name = name
+        self.dir = directory
+        self.cache = None
+        if not (os.path.isdir(self.dir) and
+                os.access(self.dir, os.R_OK | os.W_OK | os.X_OK)):
+            raise NoSuchVServer, "%s does not exist" % self.dir
+
+    def get(self, option, default = None):
+        try:
+            if self.cache:
+                return self.cache[option]
+            else:
+                f = open(os.path.join(self.dir, option), "r")
+                buf = f.read().rstrip()
+                f.close()
+                return buf
+        except:
+            if default is not None:
+                return default
+            else:
+                raise KeyError, "Key %s is not set for %s" % (option, self.name)
+
+    def update(self, option, value):
+        if self.cache:
+            return
+
+        try:
+            old_umask = os.umask(0022)
+            filename = os.path.join(self.dir, option)
+            try:
+                os.makedirs(os.path.dirname(filename), 0755)
+            except:
+                pass
+            f = open(filename, 'w')
+            if isinstance(value, list):
+                f.write("%s\n" % "\n".join(value))
+            else:
+                f.write("%s\n" % value)
+            f.close()
+            os.umask(old_umask)
+        except:
+            raise
+
+    def unset(self, option):
+        if self.cache:
+            return
+
+        try:
+            filename = os.path.join(self.dir, option)
+            os.unlink(filename)
+            try:
+                os.removedirs(os.path.dirname(filename))
+            except:
+                pass
+            return True
+        except:
+            return False
+
+    def cache_it(self):
+        self.cache = {}
+        def add_to_cache(cache, dirname, fnames):
+            for file in fnames:
+                full_name = os.path.join(dirname, file)
+                if os.path.islink(full_name):
+                    fnames.remove(file)
+                elif (os.path.isfile(full_name) and
+                      os.access(full_name, os.R_OK)):
+                    f = open(full_name, "r")
+                    cache[full_name.replace(os.path.join(self.dir, ''),
+                                            '')] = f.read().rstrip()
+                    f.close()
+        os.path.walk(self.dir, add_to_cache, self.cache)
+
 
 class VServer:
 
     INITSCRIPTS = [('/etc/rc.vinit', 'start'),
                    ('/etc/rc.d/rc', '%(runlevel)d')]
 
-    def __init__(self, name, vm_id = None, vm_running = False):
+    def __init__(self, name, vm_id = None, vm_running = None):
 
         self.name = name
-        self.config_file = "/etc/vservers/%s.conf" % name
+        self.rlimits_changed = False
         self.dir = "%s/%s" % (vserverimpl.VSERVER_BASEDIR, name)
         if not (os.path.isdir(self.dir) and
                 os.access(self.dir, os.R_OK | os.W_OK | os.X_OK)):
             raise NoSuchVServer, "no such vserver: " + name
-        self.config = {}
-        for config_file in ["/etc/vservers.conf", self.config_file]:
-            try:
-                self.config.update(self.__read_config_file(config_file))
-            except IOError, ex:
-                if ex.errno != errno.ENOENT:
-                    raise
+        self.config = VServerConfig(name, "/etc/vservers/%s" % name)
         self.remove_caps = ~vserverimpl.CAP_SAFE;
         if vm_id == None:
-            vm_id = int(self.config['S_CONTEXT'])
+            vm_id = int(self.config.get('context'))
         self.ctx = vm_id
+        if vm_running == None:
+            vm_running = self.is_running()
         self.vm_running = vm_running
 
-    config_var_re = re.compile(r"^ *([A-Z_]+)=(.*)\n?$", re.MULTILINE)
-
-    def __read_config_file(self, filename):
-
-        f = open(filename, "r")
-        data = f.read()
-        f.close()
-        config = {}
-        for m in self.config_var_re.finditer(data):
-            (key, val) = m.groups()
-            config[key] = val.strip('"')
-        return config
-
-    def __update_config_file(self, filename, newvars):
+    def have_limits_changed(self):
+        return self.rlimits_changed
 
-        # read old file, apply changes
-        f = open(filename, "r")
-        data = f.read()
-        f.close()
-        todo = newvars.copy()
+    def set_rlimit_limit(self,type,hard,soft,minimum):
+        """Generic set resource limit function for vserver"""
+        global RLIMITS
         changed = False
-        offset = 0
-        for m in self.config_var_re.finditer(data):
-            (key, val) = m.groups()
-            newval = todo.pop(key, None)
-            if newval != None:
-                data = data[:offset+m.start(2)] + str(newval) + data[offset+m.end(2):]
-                offset += len(str(newval)) - (m.end(2)-m.start(2))
-                changed = True
-        for (newkey, newval) in todo.items():
-            data += "%s=%s\n" % (newkey, newval)
-            changed = True
-
-        if not changed:
-            return
-
-        # write new file
-        newfile = filename + ".new"
-        f = open(newfile, "w")
-        f.write(data)
-        f.close()
+        try:
+            old_hard, old_soft, old_minimum = self.get_rlimit_limit(type)
+            if old_hard != VC_LIM_KEEP and old_hard <> hard: changed = True
+            if old_soft != VC_LIM_KEEP and old_soft <> soft: changed = True
+            if old_minimum != VC_LIM_KEEP and old_minimum <> minimum: changed = True
+            self.rlimits_changed = self.rlimits_changed or changed 
+        except OSError, e:
+            if self.is_running(): print "Unexpected error with getrlimit for running context %d" % self.ctx
+
+        resource_type = RLIMITS[type]
+        try:
+            ret = vserverimpl.setrlimit(self.ctx,resource_type,hard,soft,minimum)
+        except OSError, e:
+            if self.is_running(): print "Unexpected error with setrlimit for running context %d" % self.ctx
+
+    def set_rlimit_config(self,type,hard,soft,minimum):
+        """Generic set resource limit function for vserver"""
+        if hard <> VC_LIM_KEEP:
+            self.config.update('rlimits/%s.hard' % type.lower(), hard)
+        if soft <> VC_LIM_KEEP:
+            self.config.update('rlimits/%s.soft' % type.lower(), soft)
+        if minimum <> VC_LIM_KEEP:
+            self.config.update('rlimits/%s.min' % type.lower(), minimum)
+        self.set_rlimit_limit(type,hard,soft,minimum)
+
+    def get_rlimit_limit(self,type):
+        """Generic get resource configuration function for vserver"""
+        global RLIMITS
+        resource_type = RLIMITS[type]
+        try:
+            ret = vserverimpl.getrlimit(self.ctx,resource_type)
+        except OSError, e:
+            print "Unexpected error with getrlimit for context %d" % self.ctx
+            ret = self.get_rlimit_config(type)
+        return ret
 
-        # replace old file with new
-        os.rename(newfile, filename)
+    def get_rlimit_config(self,type):
+        """Generic get resource configuration function for vserver"""
+        hard = int(self.config.get("rlimits/%s.hard"%type.lower(),VC_LIM_KEEP))
+        soft = int(self.config.get("rlimits/%s.soft"%type.lower(),VC_LIM_KEEP))
+        minimum = int(self.config.get("rlimits/%s.min"%type.lower(),VC_LIM_KEEP))
+        return (hard,soft,minimum)
+
+    def set_capabilities(self, capabilities):
+        return vserverimpl.setbcaps(self.ctx, vserverimpl.text2bcaps(capabilities))
+
+    def set_capabilities_config(self, capabilities):
+        self.config.update('bcapabilities', capabilities)
+        self.set_capabilities(capabilities)
+
+    def get_capabilities(self):
+        return vserverimpl.bcaps2text(vserverimpl.getbcaps(self.ctx))
+    def get_capabilities_config(self):
+        return self.config.get('bcapabilities', '')
+
+    def set_ipaddresses(self, addresses):
+        vserverimpl.netremove(self.ctx, "all")
+        for a in addresses.split(","):
+            vserverimpl.netadd(self.ctx, a)
+
+    def set_ipaddresses_config(self, addresses):
+        i = 0
+        for a in addresses.split(","):
+            self.config.update("interfaces/%d/ip" % i, a)
+            i += 1
+        while self.config.unset("interfaces/%d/ip" % i):
+            i += 1
+        self.set_ipaddresses(addresses)
+
+    def get_ipaddresses_config(self):
+        i = 0
+        ret = []
+        while True:
+            r = self.config.get("interfaces/%d/ip" % i, '')
+            if r == '':
+                break
+            ret += [r]
+            i += 1
+        return ",".join(ret)
+
+    def get_ipaddresses(self):
+        # No clean way to do this right now.
+        return None
 
     def __do_chroot(self):
-
+        self.config.cache_it()
         os.chroot(self.dir)
         os.chdir("/")
 
@@ -133,10 +267,12 @@ class VServer:
         return result
 
     def set_disklimit(self, block_limit):
-
         # block_limit is in kB
         if block_limit == 0:
-            vserverimpl.unsetdlimit(self.dir, self.ctx)
+            try:
+                vserverimpl.unsetdlimit(self.dir, self.ctx)
+            except OSError, e:
+                print "Unexpected error with unsetdlimit for context %d" % self.ctx
             return
 
         if self.vm_running:
@@ -147,14 +283,24 @@ class VServer:
             block_usage = self.disk_blocks
             inode_usage = self.disk_inodes
 
-        vserverimpl.setdlimit(self.dir,
-                              self.ctx,
-                              block_usage,
-                              block_limit,
-                              inode_usage,
-                              vserverimpl.DLIMIT_INF,  # inode limit
-                              2)   # %age reserved for root
 
+        try:
+            vserverimpl.setdlimit(self.dir,
+                                  self.ctx,
+                                  block_usage,
+                                  block_limit,
+                                  inode_usage,
+                                  vserverimpl.DLIMIT_INF,  # inode limit
+                                  2)   # %age reserved for root
+        except OSError, e:
+            print "Unexpected error with setdlimit for context %d" % self.ctx
+
+
+        self.config.update('dlimits/0/space_total', block_limit)
+
+    def is_running(self):
+        return vserverimpl.isrunning(self.ctx)
+    
     def get_disklimit(self):
 
         try:
@@ -174,40 +320,24 @@ class VServer:
         configuration file. This method does not modify the kernel CPU
         scheduling parameters for this context. """
 
-        if cpu_share == int(self.config.get("CPULIMIT", -1)):
-            return
-        cpu_guaranteed = sched_flags & SCHED_CPU_GUARANTEED
-        cpu_config = { "CPULIMIT": cpu_share, "CPUGUARANTEED": cpu_guaranteed }
-        self.update_resources(cpu_config)
+        if sched_flags & SCHED_CPU_GUARANTEED:
+            cpu_guaranteed = cpu_share
+        else:
+            cpu_guaranteed = 0
+        self.config.update('sched/fill-rate2', cpu_share)
+        self.config.update('sched/fill-rate', cpu_guaranteed)
+
         if self.vm_running:
             self.set_sched(cpu_share, sched_flags)
 
     def set_sched(self, cpu_share, sched_flags = 0):
-
         """ Update kernel CPU scheduling parameters for this context. """
-
         vserverimpl.setsched(self.ctx, cpu_share, sched_flags)
 
     def get_sched(self):
         # have no way of querying scheduler right now on a per vserver basis
         return (-1, False)
 
-    def set_memlimit(self, limit):
-        ret = vserverimpl.setrlimit(self.ctx,5,limit)
-        return ret
-
-    def get_memlimit(self):
-        ret = vserverimpl.getrlimit(self.ctx,5)
-        return ret
-    
-    def set_tasklimit(self, limit):
-        ret = vserverimpl.setrlimit(self.ctx,6,limit)
-        return ret
-
-    def get_tasklimit(self):
-        ret = vserverimpl.getrlimit(self.ctx,6)
-        return ret
-
     def set_bwlimit(self, minrate = bwlimit.bwmin, maxrate = None,
                     exempt_min = None, exempt_max = None,
                     share = None, dev = "eth0"):
@@ -233,11 +363,10 @@ class VServer:
     def __do_chcontext(self, state_file):
 
         if state_file:
-            print >>state_file, "S_CONTEXT=%u" % self.ctx
-            print >>state_file, "S_PROFILE="
+            print >>state_file, "%u" % self.ctx
             state_file.close()
 
-        if vserverimpl.chcontext(self.ctx):
+        if vserverimpl.chcontext(self.ctx, vserverimpl.text2bcaps(self.get_capabilities_config())):
             self.set_resources()
             vserverimpl.setup_done(self.ctx)
 
@@ -258,23 +387,24 @@ class VServer:
                          ([], filter_fn))[0]
         garbage += filter(os.path.isfile, map((LOCKDIR + "/").__add__,
                                               os.listdir(LOCKDIR)))
-        for f in garbage:
-            os.unlink(f)
+        if False:
+            for f in garbage:
+                os.unlink(f)
 
         # set the initial runlevel
         f = open(RUNDIR + "/utmp", "w")
-        utmp.set_runlevel(f, runlevel)
+        vserverimpl.setrunlevel(f, runlevel)
         f.close()
 
         # mount /proc and /dev/pts
-        self.__do_mount("none", "/proc", "proc")
+        self.__do_mount("none", self.dir, "/proc", "proc")
         # XXX - magic mount options
-        self.__do_mount("none", "/dev/pts", "devpts", 0, "gid=5,mode=0620")
+        self.__do_mount("none", self.dir, "/dev/pts", "devpts", 0, "gid=5,mode=0620")
 
     def __do_mount(self, *mount_args):
 
         try:
-            mountimpl.mount(*mount_args)
+            vserverimpl.mount(*mount_args)
         except OSError, ex:
             if ex.errno == errno.EBUSY:
                 # assume already mounted
@@ -282,14 +412,12 @@ class VServer:
             raise ex
 
     def enter(self):
-
-        state_file = open("/var/run/vservers/%s.ctx" % self.name, "w")
         self.__do_chroot()
-        self.__do_chcontext(state_file)
+        self.__do_chcontext(None)
 
     def start(self, wait, runlevel = 3):
-
         self.vm_running = True
+        self.rlimits_changed = False
 
         child_pid = os.fork()
         if child_pid == 0:
@@ -299,14 +427,17 @@ class VServer:
                 os.setsid()
 
                 # open state file to record vserver info
-                state_file = open("/var/run/vservers/%s.ctx" % self.name, "w")
+                state_file = open("/var/run/vservers/%s" % self.name, "w")
 
                 # use /dev/null for stdin, /var/log/boot.log for stdout/err
-                os.close(0)
-                os.close(1)
-                os.open("/dev/null", os.O_RDONLY)
+                fd = os.open("/dev/null", os.O_RDONLY)
+                if fd != 0:
+                    os.dup2(fd, 0)
+                    os.close(fd)
                 self.__do_chroot()
                 log = open("/var/log/boot.log", "w", 0)
+                if log.fileno() != 1:
+                    os.dup2(log.fileno(), 1)
                 os.dup2(1, 2)
 
                 print >>log, ("%s: starting the virtual server %s" %
@@ -317,39 +448,18 @@ class VServer:
 
                 # execute each init script in turn
                 # XXX - we don't support all scripts that vserver script does
-                cmd_pid = 0
-                first_child = True
-                for cmd in self.INITSCRIPTS + [None]:
-                    # wait for previous command to terminate, unless it
-                    # is the last one and the caller has specified to wait
-                    if cmd_pid and (cmd != None or wait):
-                        try:
-                            os.waitpid(cmd_pid, 0)
-                        except:
-                            print >>log, "error waiting for %s:" % cmd_pid
-                            traceback.print_exc()
-
-                    # end of list
-                    if cmd == None:
-                        os._exit(0)
-
-                    # fork and exec next command
-                    cmd_pid = os.fork()
-                    if cmd_pid == 0:
-                        try:
-                            # enter vserver context
-                            self.__do_chcontext(state_file)
-                            arg_subst = { 'runlevel': runlevel }
-                            cmd_args = [cmd[0]] + map(lambda x: x % arg_subst,
-                                                      cmd[1:])
-                            print >>log, "executing '%s'" % " ".join(cmd_args)
-                            os.execl(cmd[0], *cmd_args)
-                        except:
-                            traceback.print_exc()
-                            os._exit(1)
-                    else:
-                        # don't want to write state_file multiple times
-                        state_file = None
+                self.__do_chcontext(state_file)
+                for cmd in self.INITSCRIPTS:
+                     try:
+                         # enter vserver context
+                         arg_subst = { 'runlevel': runlevel }
+                         cmd_args = [cmd[0]] + map(lambda x: x % arg_subst,
+                                                   cmd[1:])
+                         print >>log, "executing '%s'" % " ".join(cmd_args)
+                         os.spawnvp(os.P_NOWAIT,cmd[0],cmd_args)
+                     except:
+                         traceback.print_exc()
+                         os._exit(1)
 
             # we get here due to an exception in the top-level child process
             except Exception, ex:
@@ -366,32 +476,46 @@ class VServer:
 
         pass
 
-    def update_resources(self, resources):
-
-        self.config.update(resources)
-
-        # write new values to configuration file
-        self.__update_config_file(self.config_file, resources)
-
     def init_disk_info(self):
-
-        (self.disk_inodes, self.disk_blocks, size) = vduimpl.vdu(self.dir)
-
-        return size
+        cmd = "/usr/sbin/vdu --script --space --inodes --blocksize 1024 --xid %d %s" % (self.ctx, self.dir)
+        p = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE,
+                             stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+                             close_fds=True)
+        p.stdin.close()
+        line = p.stdout.readline()
+        if not line:
+            sys.stderr.write(p.stderr.read())
+        p.stdout.close()
+        p.stderr.close()
+        ret = p.wait()
+
+        (space, inodes) = line.split()
+        self.disk_inodes = int(inodes)
+        self.disk_blocks = int(space)
+        #(self.disk_inodes, self.disk_blocks) = vduimpl.vdu(self.dir)
+
+        return self.disk_blocks * 1024
 
     def stop(self, signal = signal.SIGKILL):
-
         vserverimpl.killall(self.ctx, signal)
         self.vm_running = False
+        self.rlimits_changed = False
 
 
 
 def create(vm_name, static = False, ctor = VServer):
 
-    options = []
+    options = ['vuseradd']
     if static:
         options += ['--static']
-    runcmd.run('vuseradd', options + [vm_name])
+    ret = os.spawnvp(os.P_WAIT, 'vuseradd', options + [vm_name])
+    if !os.WIFEXITED(ret) || os.WEXITSTATUS(ret) != 0:
+        out = "system command ('%s') " % options
+        if os.WIFEXITED(ret):
+            out += "failed, rc = %d" % os.WEXITSTATUS(ret)
+        else:
+            out += "killed by signal %d" % os.WTERMSIG(ret)
+        raise SystemError, out
     vm_id = pwd.getpwnam(vm_name)[2]
 
     return ctor(vm_name, vm_id)