post-review fixes + cleanup + some minor fixes

server-tools/instance-manager/buffer.cc:
  coding style fixes
server-tools/instance-manager/buffer.h:
  wrong constructor initialisation fixed
server-tools/instance-manager/commands.cc:
  cleanup
server-tools/instance-manager/guardian.cc:
  cleanup + added lock/unlock routines
server-tools/instance-manager/guardian.h:
  GUARD_NODE moved to the header
server-tools/instance-manager/instance.cc:
  Fix for the linuxthreads/POSIX signal handling problem (see comments in the code)
server-tools/instance-manager/instance.h:
  condition variable renamed and commented
server-tools/instance-manager/instance_map.cc:
  We need to refresh guardian during flush_instances
server-tools/instance-manager/instance_map.h:
  removed obsolete function declaration
server-tools/instance-manager/instance_options.cc:
  added caching of computed values
server-tools/instance-manager/instance_options.h:
  added vars to cache some option values
server-tools/instance-manager/listener.cc:
  check whether we are running on the linux threads
server-tools/instance-manager/manager.cc:
  lock guardian before init()
server-tools/instance-manager/parse_output.cc:
  cleanup
server-tools/instance-manager/priv.cc:
  added global variables to detect whether we are running on the LinuxThreads
server-tools/instance-manager/priv.h:
  added global variables to detect whether we are running on the LinuxThreads

server-tools/instance-manager/buffer.cc

@@ -79,13 +79,13 @@ int Buffer::reserve(uint position, uint len_arg)
   if (position + len_arg >= MAX_BUFFER_SIZE)
     goto err;
 
-  if (position + len_arg>= buffer_size)
+  if (position + len_arg >= buffer_size)
   {
     buffer= (char *) my_realloc(buffer,
                                 min(MAX_BUFFER_SIZE,
                                     max((uint) (buffer_size*1.5),
                                         position + len_arg)), MYF(0));
-    if (buffer == NULL)
+    if (!(buffer))
       goto err;
     buffer_size= (uint) (buffer_size*1.5);
   }

server-tools/instance-manager/buffer.h

@@ -41,7 +41,7 @@ class Buffer
   int error;
 public:
   Buffer(size_t buffer_size_arg= BUFFER_INITIAL_SIZE)
-    :buffer_size(BUFFER_INITIAL_SIZE), error(0)
+    :buffer_size(buffer_size_arg), error(0)
   {
     /*
       As append() will invokes realloc() anyway, it's ok if malloc returns 0

server-tools/instance-manager/commands.cc

@@ -170,7 +170,7 @@ int Show_instance_status::do_command(struct st_net *net,
     Instance *instance;
 
     store_to_string(&send_buff, (char *) instance_name, &position);
-    if ((instance= instance_map->find(instance_name, strlen(instance_name))) == NULL)
+    if (!(instance= instance_map->find(instance_name, strlen(instance_name))))
       goto err;
     if (instance->is_running())
     {
@@ -201,7 +201,7 @@ int Show_instance_status::do_command(struct st_net *net,
 
 int Show_instance_status::execute(struct st_net *net, ulong connection_id)
 {
-  if (instance_name != NULL)
+  if ((instance_name))
   {
     if (do_command(net, instance_name))
       return ER_OUT_OF_RESOURCES;
@@ -257,14 +257,13 @@ int Show_instance_options::do_command(struct st_net *net,
   {
     Instance *instance;
 
-    if ((instance= instance_map->
-                   find(instance_name, strlen(instance_name))) == NULL)
+    if (!(instance= instance_map->find(instance_name, strlen(instance_name))))
       goto err;
     store_to_string(&send_buff, (char *) "instance_name", &position);
     store_to_string(&send_buff, (char *) instance_name, &position);
     if (my_net_write(net, send_buff.buffer, (uint) position))
       goto err;
-    if (instance->options.mysqld_path != NULL)
+    if ((instance->options.mysqld_path))
     {
       position= 0;
       store_to_string(&send_buff, (char *) "mysqld-path", &position);
@@ -276,7 +275,7 @@ int Show_instance_options::do_command(struct st_net *net,
         goto err;
     }
 
-    if (instance->options.nonguarded != NULL)
+    if ((instance->options.nonguarded))
     {
       position= 0;
       store_to_string(&send_buff, (char *) "nonguarded", &position);
@@ -317,7 +316,7 @@ int Show_instance_options::do_command(struct st_net *net,
 
 int Show_instance_options::execute(struct st_net *net, ulong connection_id)
 {
-  if (instance_name != NULL)
+  if ((instance_name))
   {
     if (do_command(net, instance_name))
       return ER_OUT_OF_RESOURCES;
@@ -351,10 +350,10 @@ int Start_instance::execute(struct st_net *net, ulong connection_id)
   }
   else
   {
-    if (err_code= instance->start())
+    if ((err_code= instance->start()))
       return err_code;
 
-    if (instance->options.nonguarded == NULL)
+    if (!(instance->options.nonguarded))
         instance_map->guardian->guard(instance);
 
     net_send_ok(net, connection_id);
@@ -385,7 +384,7 @@ int Stop_instance::execute(struct st_net *net, ulong connection_id)
   }
   else
   {
-    if (instance->options.nonguarded == NULL)
+    if (!(instance->options.nonguarded))
         instance_map->guardian->
                stop_guard(instance);
     if ((err_code= instance->stop()))

server-tools/instance-manager/guardian.cc

@@ -29,23 +29,6 @@
 #include <signal.h>
 
 
-/*
-  The Guardian list node structure. Guardian utilizes it to store
-  guarded instances plus some additional info.
-*/
-
-struct GUARD_NODE
-{
-  Instance *instance;
-  /* state of an instance (i.e. STARTED, CRASHED, etc.) */
-  int state;
-  /* the amount of attemts to restart instance (cleaned up at success) */
-  int restart_counter;
-  /* triggered at a crash */
-  time_t crash_moment;
-  /* General time field. Used to provide timeouts (at shutdown and restart) */
-  time_t last_checked;
-};
 
 
 C_MODE_START
@@ -99,9 +82,9 @@ void Guardian_thread::request_shutdown(bool stop_instances_arg)
 void Guardian_thread::process_instance(Instance *instance,
                                        GUARD_NODE *current_node,
                                        LIST **guarded_instances,
-                                       LIST *elem)
+                                       LIST *node)
 {
-  int waitchild= Instance::DEFAULT_SHUTDOWN_DELAY;
+  uint waitchild= (uint) Instance::DEFAULT_SHUTDOWN_DELAY;
   /* The amount of times, Guardian attempts to restart an instance */
   int restart_retry= 100;
   time_t current_time= time(NULL);
@@ -109,20 +92,20 @@ void Guardian_thread::process_instance(Instance *instance,
   if (current_node->state == STOPPING)
   {
     /* this brach is executed during shutdown */
-    if (instance->options.shutdown_delay != NULL)
-      waitchild= atoi(instance->options.shutdown_delay);
+    if (instance->options.shutdown_delay_val)
+      waitchild= instance->options.shutdown_delay_val;
 
-    /* this returns true if and only if an instance was stopped for shure */
+    /* this returns true if and only if an instance was stopped for sure */
     if (instance->is_crashed())
-      *guarded_instances= list_delete(*guarded_instances, elem);
-    else if (current_time - current_node->last_checked > waitchild)
+      *guarded_instances= list_delete(*guarded_instances, node);
+    else if ( (uint) (current_time - current_node->last_checked) > waitchild)
     {
       instance->kill_instance(SIGKILL);
       /*
-          Later we do elem= elem->next. This is ok, as we are only removing
+        Later we do node= node->next. This is ok, as we are only removing
         the node from the list. The pointer to the next one is still valid.
       */
-        *guarded_instances= list_delete(*guarded_instances, elem);
+      *guarded_instances= list_delete(*guarded_instances, node);
     }
 
     return;
@@ -174,11 +157,12 @@ void Guardian_thread::process_instance(Instance *instance,
         {
           instance->start();
           current_node->last_checked= current_time;
-          ((GUARD_NODE *) elem->data)->restart_counter++;
-          log_info("guardian: starting instance %s",
+          current_node->restart_counter++;
+          log_info("guardian: restarting instance %s",
                    instance->options.instance_name);
         }
-        else current_node->state= CRASHED_AND_ABANDONED;
+        else
+          current_node->state= CRASHED_AND_ABANDONED;
       }
       break;
     case CRASHED_AND_ABANDONED:
@@ -205,7 +189,7 @@ void Guardian_thread::process_instance(Instance *instance,
 void Guardian_thread::run()
 {
   Instance *instance;
-  LIST *elem;
+  LIST *node;
   struct timespec timeout;
 
   thread_registry.register_thread(&thread_info);
@@ -216,23 +200,23 @@ void Guardian_thread::run()
   /* loop, until all instances were shut down at the end */
   while (!(shutdown_requested && (guarded_instances == NULL)))
   {
-    elem= guarded_instances;
+    node= guarded_instances;
 
-    while (elem != NULL)
+    while (node != NULL)
     {
       struct timespec timeout;
 
-      GUARD_NODE *current_node= (GUARD_NODE *) elem->data;
-      instance= ((GUARD_NODE *) elem->data)->instance;
-      process_instance(instance, current_node, &guarded_instances, elem);
+      GUARD_NODE *current_node= (GUARD_NODE *) node->data;
+      instance= ((GUARD_NODE *) node->data)->instance;
+      process_instance(instance, current_node, &guarded_instances, node);
 
-      elem= elem->next;
+      node= node->next;
     }
     timeout.tv_sec= time(NULL) + monitoring_interval;
     timeout.tv_nsec= 0;
 
     /* check the loop predicate before sleeping */
-    if (!(shutdown_requested && (guarded_instances == NULL)))
+    if (!(shutdown_requested && (!(guarded_instances))))
       pthread_cond_timedwait(&COND_guardian, &LOCK_guardian, &timeout);
   }
 
@@ -262,6 +246,8 @@ int Guardian_thread::is_stopped()
   SYNOPSYS
     Guardian_thread::init()
 
+  NOTE: One should always lock guardian before calling this routine.
+
   RETURN
     0 - ok
     1 - error occured
@@ -273,14 +259,22 @@ int Guardian_thread::init()
   Instance_map::Iterator iterator(instance_map);
 
   instance_map->lock();
+  /* clear the list of guarded instances */
+  free_root(&alloc, MYF(0));
+  init_alloc_root(&alloc, MEM_ROOT_BLOCK_SIZE, 0);
+  guarded_instances= NULL;
+
   while ((instance= iterator.next()))
   {
-    if ((instance->options.nonguarded == NULL))
-      if (guard(instance))
+    if (!(instance->options.nonguarded))
+      if (guard(instance, TRUE))                /* do not lock guardian */
+      {
+        instance_map->unlock();
         return 1;
       }
-  instance_map->unlock();
+  }
 
+  instance_map->unlock();
   return 0;
 }
 
@@ -291,6 +285,8 @@ int Guardian_thread::init()
   SYNOPSYS
     guard()
     instance           the instance to be guarded
+    nolock             whether we prefer do not lock Guardian here,
+                       but use external locking instead
 
   DESCRIPTION
 
@@ -302,7 +298,7 @@ int Guardian_thread::init()
     1 - error occured
 */
 
-int Guardian_thread::guard(Instance *instance)
+int Guardian_thread::guard(Instance *instance, bool nolock)
 {
   LIST *node;
   GUARD_NODE *content;
@@ -310,7 +306,7 @@ int Guardian_thread::guard(Instance *instance)
   node= (LIST *) alloc_root(&alloc, sizeof(LIST));
   content= (GUARD_NODE *) alloc_root(&alloc, sizeof(GUARD_NODE));
 
-  if ((node == NULL) || (content == NULL))
+  if ((!(node)) || (!(content)))
     return 1;
   /* we store the pointers to instances from the instance_map's MEM_ROOT */
   content->instance= instance;
@@ -319,16 +315,21 @@ int Guardian_thread::guard(Instance *instance)
   content->state= NOT_STARTED;
   node->data= (void *) content;
 
+  if (nolock)
+    guarded_instances= list_add(guarded_instances, node);
+  else
+  {
     pthread_mutex_lock(&LOCK_guardian);
     guarded_instances= list_add(guarded_instances, node);
     pthread_mutex_unlock(&LOCK_guardian);
+  }
 
   return 0;
 }
 
 
 /*
-  TODO: perhaps it would make sense to create a pool of the LIST elements
+  TODO: perhaps it would make sense to create a pool of the LIST nodeents
   and give them upon request. Now we are loosing a bit of memory when
   guarded instance was stopped and then restarted (since we cannot free just
   a piece of the MEM_ROOT).
@@ -419,3 +420,15 @@ int Guardian_thread::stop_instances(bool stop_instances_arg)
   }
   return 0;
 }
+
+
+int Guardian_thread::lock()
+{
+  return pthread_mutex_lock(&LOCK_guardian);
+}
+
+
+int Guardian_thread::unlock()
+{
+  return pthread_mutex_unlock(&LOCK_guardian);
+}

server-tools/instance-manager/guardian.h

@@ -60,22 +60,47 @@ struct Guardian_thread_args
 class Guardian_thread: public Guardian_thread_args
 {
 public:
+  /* states of an instance */
+  enum INSTANCE_STATE { NOT_STARTED= 1, STARTING, STARTED, JUST_CRASHED,
+                        CRASHED, CRASHED_AND_ABANDONED, STOPPING };
+
+  /*
+    The Guardian list node structure. Guardian utilizes it to store
+    guarded instances plus some additional info.
+  */
+
+  struct GUARD_NODE
+  {
+    Instance *instance;
+    /* state of an instance (i.e. STARTED, CRASHED, etc.) */
+    INSTANCE_STATE state;
+    /* the amount of attemts to restart instance (cleaned up at success) */
+    int restart_counter;
+    /* triggered at a crash */
+    time_t crash_moment;
+    /* General time field. Used to provide timeouts (at shutdown and restart) */
+    time_t last_checked;
+  };
+
+
   Guardian_thread(Thread_registry &thread_registry_arg,
                   Instance_map *instance_map_arg,
                   uint monitoring_interval_arg);
   ~Guardian_thread();
   /* Main funtion of the thread */
   void run();
-  /* Initialize list of guarded instances */
+  /* Initialize or refresh the list of guarded instances */
   int init();
   /* Request guardian shutdown. Stop instances if needed */
   void request_shutdown(bool stop_instances);
   /* Start instance protection */
-  int guard(Instance *instance);
+  int guard(Instance *instance, bool nolock= FALSE);
   /* Stop instance protection */
   int stop_guard(Instance *instance);
   /* Returns true if guardian thread is stopped */
   int is_stopped();
+  int lock();
+  int unlock();
 
 public:
   pthread_cond_t COND_guardian;
@@ -89,9 +114,6 @@ class Guardian_thread: public Guardian_thread_args
   int stopped;
 
 private:
-  /* states of an instance */
-  enum { NOT_STARTED= 1, STARTING, STARTED, JUST_CRASHED, CRASHED,
-         CRASHED_AND_ABANDONED, STOPPING };
   pthread_mutex_t LOCK_guardian;
   Thread_info thread_info;
   LIST *guarded_instances;

server-tools/instance-manager/instance.cc

@@ -22,6 +22,8 @@
 #include "mysql_manager_error.h"
 #include "log.h"
 #include "instance_map.h"
+#include "priv.h"
+
 #include <my_sys.h>
 #include <signal.h>
 #include <m_string.h>
@@ -30,6 +32,13 @@
 
 C_MODE_START
 
+/*
+  Proxy thread is a simple way to avoid all pitfalls of the threads
+  implementation in the OS (e.g. LinuxThreads). With such a thread we
+  don't have to process SIGCHLD, which is a tricky business if we want
+  to do it in a portable way.
+*/
+
 pthread_handler_decl(proxy, arg)
 {
   Instance *instance= (Instance *) arg;
@@ -111,7 +120,26 @@ void Instance::fork_and_monitor()
     log_info("cannot fork() to start instance %s", options.instance_name);
     return;
   default:
-    wait(NULL);
+    /*
+      Here we wait for the child created. This process differs for systems
+      running LinuxThreads and POSIX Threads compliant systems. This is because
+      according to POSIX we could wait() for a child in any thread of the
+      process. While LinuxThreads require that wait() is called by the thread,
+      which created the child.
+      On the other hand we could not expect mysqld to return the pid, we
+      got in from fork(), to wait4() fucntion when running on LinuxThreads.
+      This is because MySQL shutdown thread is not the one, which was created
+      by our fork() call.
+      So basically we have two options: whether the wait() call returns only in
+      the creator thread, but we cannot use waitpid() since we have no idea
+      which pid we should wait for (in fact it should be the pid of shutdown
+      thread, but we don't know this one). Or we could use waitpid(), but
+      couldn't use wait(), because it could return in any wait() in the program.
+    */
+    if (linuxthreads)
+      wait(NULL);                               /* LinuxThreads were detected */
+    else
+      waitpid(pid, NULL, 0);
     /* set instance state to crashed */
     pthread_mutex_lock(&LOCK_instance);
     crashed= 1;
@@ -122,7 +150,7 @@ void Instance::fork_and_monitor()
       is needed if a user issued command to stop an instance via
       mysql connection. This is not the case if Guardian stop the thread.
     */
-    pthread_cond_signal(&COND_instance_restarted);
+    pthread_cond_signal(&COND_instance_stopped);
     /* wake guardian */
     pthread_cond_signal(&instance_map->guardian->COND_guardian);
     /* thread exits */
@@ -136,14 +164,14 @@ void Instance::fork_and_monitor()
 Instance::Instance(): crashed(0)
 {
   pthread_mutex_init(&LOCK_instance, 0);
-  pthread_cond_init(&COND_instance_restarted, 0);
+  pthread_cond_init(&COND_instance_stopped, 0);
 }
 
 
 Instance::~Instance()
 {
+  pthread_cond_destroy(&COND_instance_stopped);
   pthread_mutex_destroy(&LOCK_instance);
-  pthread_cond_destroy(&COND_instance_restarted);
 }
 
 
@@ -168,7 +196,7 @@ bool Instance::is_running()
   bool return_val;
 
   if (options.mysqld_port)
-    port= atoi(strchr(options.mysqld_port, '=') + 1);
+    port= options.mysqld_port_val;
 
   if (options.mysqld_socket)
     socket= strchr(options.mysqld_socket, '=') + 1;
@@ -226,10 +254,10 @@ int Instance::stop()
 {
   pid_t pid;
   struct timespec timeout;
-  int waitchild= DEFAULT_SHUTDOWN_DELAY;
+  uint waitchild= (uint)  DEFAULT_SHUTDOWN_DELAY;
 
-  if (options.shutdown_delay != NULL)
-    waitchild= atoi(options.shutdown_delay);
+  if (options.shutdown_delay_val)
+    waitchild= options.shutdown_delay_val;
 
   kill_instance(SIGTERM);
   /* sleep on condition to wait for SIGCHLD */
@@ -243,7 +271,7 @@ int Instance::stop()
   {
     int status;
 
-    status= pthread_cond_timedwait(&COND_instance_restarted,
+    status= pthread_cond_timedwait(&COND_instance_stopped,
                                    &LOCK_instance,
                                    &timeout);
     if (status == ETIMEDOUT)

server-tools/instance-manager/instance.h

@@ -57,7 +57,11 @@ class Instance
   */
   int crashed;
   pthread_mutex_t LOCK_instance;
-  pthread_cond_t COND_instance_restarted;
+  /*
+    This condition variable is used to wake threads waiting for instance to
+    stop in Instance::stop()
+  */
+  pthread_cond_t COND_instance_stopped;
   Instance_map *instance_map;
 };
 

server-tools/instance-manager/instance_map.cc

@@ -151,12 +151,15 @@ int Instance_map::flush_instances()
 {
   int rc;
 
+  guardian->lock();
   pthread_mutex_lock(&LOCK_instance_map);
   hash_free(&hash);
   hash_init(&hash, default_charset_info, START_HASH_SIZE, 0, 0,
             get_instance_key, delete_instance, 0);
   pthread_mutex_unlock(&LOCK_instance_map);
   rc= load();
+  guardian->init();
+  guardian->unlock();
   return rc;
 }
 
@@ -183,6 +186,7 @@ int Instance_map::complete_initialization()
   Instance *instance;
   uint i= 0;
 
+
   if (hash.records == 0)                        /* no instances found */
   {
     if ((instance= new Instance) == 0)
@@ -191,6 +195,7 @@ int Instance_map::complete_initialization()
     if (instance->init("mysqld") || add_instance(instance))
       goto err_instance;
 
+
     /*
       After an instance have been added to the instance_map,
       hash_free should handle it's deletion => goto err, not
@@ -227,6 +232,7 @@ int Instance_map::load()
   const char *argv_options[3];
   char **argv= (char **) &argv_options;
 
+
   /* the name of the program may be orbitrary here in fact */
   argv_options[0]= "mysqlmanager";
   if (first_option != NULL)

server-tools/instance-manager/instance_map.h

@@ -57,7 +57,6 @@ class Instance_map
 public:
   /* returns a pointer to the instance or NULL, if there is no such instance */
   Instance *find(const char *name, uint name_len);
-  Instance *find(uint instance_number);
 
   int flush_instances();
   int lock();

server-tools/instance-manager/instance_options.cc

@@ -79,7 +79,7 @@ int Instance_options::get_pid_filename(char *result)
   const char *pid_file= mysqld_pid_file;
   char datadir[MAX_PATH_LEN];
 
-  if (mysqld_datadir == NULL)
+  if (!(mysqld_datadir))
   {
     /* we might get an error here if we have wrong path to the mysqld binary */
     if (get_default_option(datadir, sizeof(datadir), "--datadir"))
@@ -128,16 +128,22 @@ int Instance_options::complete_initialization(const char *default_path,
 {
   const char *tmp;
 
-  if (mysqld_path == NULL)
+  if (!(mysqld_path))
   {
     if (!(mysqld_path= strdup_root(&alloc, default_path)))
       goto err;
   }
 
+  if (mysqld_port)
+    mysqld_port_val= atoi(strchr(mysqld_port, '=') + 1);
+
+  if (shutdown_delay)
+    shutdown_delay_val= atoi(shutdown_delay);
+
   if (!(tmp= strdup_root(&alloc, "--no-defaults")))
     goto err;
 
-  if (mysqld_pid_file == NULL)
+  if (!(mysqld_pid_file))
   {
     char pidfilename[MAX_PATH_LEN];
     char hostname[MAX_PATH_LEN];
@@ -265,7 +271,7 @@ int Instance_options::add_to_argv(const char* option)
 {
   DBUG_ASSERT(filled_default_options < MAX_NUMBER_OF_DEFAULT_OPTIONS);
 
-  if (option != NULL)
+  if ((option))
     argv[filled_default_options++]= (char *) option;
   return 0;
 }

server-tools/instance-manager/instance_options.h

@@ -37,9 +37,10 @@ class Instance_options
 {
 public:
   Instance_options() :
-    mysqld_socket(0), mysqld_datadir(0), mysqld_bind_address(0),
-    mysqld_pid_file(0), mysqld_port(0), mysqld_path(0), nonguarded(0),
-    shutdown_delay(0), filled_default_options(0)
+    mysqld_socket(0), mysqld_datadir(0),
+    mysqld_bind_address(0), mysqld_pid_file(0), mysqld_port(0),
+    mysqld_port_val(0), mysqld_path(0), nonguarded(0), shutdown_delay(0),
+    shutdown_delay_val(0), filled_default_options(0)
   {}
   ~Instance_options();
   /* fills in argv */
@@ -68,11 +69,13 @@ class Instance_options
   const char *mysqld_bind_address;
   const char *mysqld_pid_file;
   const char *mysqld_port;
-  uint instance_name_len;
+  uint mysqld_port_val;
   const char *instance_name;
+  uint instance_name_len;
   const char *mysqld_path;
   const char *nonguarded;
   const char *shutdown_delay;
+  uint shutdown_delay_val;
   /* this value is computed and cashed here */
   DYNAMIC_ARRAY options_array;
 private:

server-tools/instance-manager/listener.cc

@@ -31,6 +31,7 @@
 #include "instance_map.h"
 #include "log.h"
 #include "mysql_connection.h"
+#include "priv.h"
 
 
 /*
@@ -82,6 +83,12 @@ void Listener_thread::run()
   int arg= 1;                             /* value to be set by setsockopt */
   int unix_socket;
   uint im_port;
+  /* we use this var to check whether we are running on LinuxThreads */
+  pid_t thread_pid;
+
+  thread_pid= getpid();
+  /* set global variable */
+  linuxthreads= (thread_pid != manager_pid);
 
   thread_registry.register_thread(&thread_info);
 

server-tools/instance-manager/manager.cc

@@ -16,6 +16,7 @@
 
 #include "manager.h"
 
+#include "priv.h"
 #include "thread_registry.h"
 #include "listener.h"
 #include "instance_map.h"
@@ -75,11 +76,13 @@ void manager(const Options &options)
   Listener_thread_args listener_args(thread_registry, options, user_map,
                                      instance_map);
 
+  manager_pid= getpid();
   instance_map.guardian= &guardian_thread;
 
   if (instance_map.init() || user_map.init())
       return;
 
+
   if (instance_map.load())
   {
     log_error("Cannot init instances repository. This might be caused by "
@@ -170,7 +173,12 @@ void manager(const Options &options)
   */
   init_thr_alarm(10);
   /* init list of guarded instances */
+  guardian_thread.lock();
+
   guardian_thread.init();
+
+  guardian_thread.unlock();
+
   /*
     After the list of guarded instances have been initialized,
     Guardian should start them.

server-tools/instance-manager/parse_output.cc

@@ -53,7 +53,7 @@ int parse_output_and_get_value(const char *command, const char *word,
 
   wordlen= strlen(word);
 
-  if ((output= popen(command, "r")) == NULL)
+  if (!(output= popen(command, "r")))
     goto err;
 
   /*

server-tools/instance-manager/priv.cc

@@ -16,6 +16,15 @@
 
 #include "priv.h"
 
+/* the pid of the manager process (of the signal thread on the LinuxThreads) */
+pid_t manager_pid;
+
+/*
+  This flag is set if mysqlmanager has detected that it is running on the
+  system using LinuxThreads
+*/
+bool linuxthreads;
+
 /*
   The following string must be less then 80 characters, as
   mysql_connection.cc relies on it

server-tools/instance-manager/priv.h

@@ -16,6 +16,18 @@
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 
+#include <unistd.h>
+
+
+/* the pid of the manager process (of the signal thread on the LinuxThreads) */
+extern pid_t manager_pid;
+
+/*
+  This flag is set if mysqlmanager has detected that it is running on the
+  system using LinuxThreads
+*/
+extern bool linuxthreads;
+
 extern const char mysqlmanager_version[];
 extern const int mysqlmanager_version_length;