X-Git-Url: http://xvm.mit.edu/gitweb/invirt/third/libt4.git/blobdiff_plain/7312c5fd3b74fd9cad485121bc31fc501accd355..eeab3e6cade87c1fe0a5f3d93522e12ccb9ec2ab:/config.cc

diff --git a/config.cc b/config.cc
index 04c869e..9319abe 100644
--- a/config.cc
+++ b/config.cc
@@ -8,6 +8,13 @@
 #include "tprintf.h"
 #include "lang/verify.h"
 
+using namespace std::chrono;
+using std::string;
+using std::vector;
+using std::thread;
+using std::ostringstream;
+using std::istringstream;
+
 // The config module maintains views. As a node joins or leaves a
 // view, the next view will be the same as previous view, except with
 // the new node added or removed. The first view contains only node
@@ -41,8 +48,8 @@
 // date.
 
 config::config(
-        const std::string &_first,
-        const std::string &_me,
+        const string &_first,
+        const string &_me,
         config_view_change *_vc)
     : my_view_id(0), first(_first), me(_me), vc(_vc)
 {
@@ -54,50 +61,49 @@ config::config(
 
     {
         lock ml(cfg_mutex);
-        reconstruct();
-        std::thread(&config::heartbeater, this).detach();
+        reconstruct(ml);
+        thread(&config::heartbeater, this).detach();
     }
 }
 
 void
-config::restore(const std::string &s)
+config::restore(const string &s)
 {
     lock ml(cfg_mutex);
     paxos_acceptor->restore(s);
-    reconstruct();
+    reconstruct(ml);
 }
 
 void
-config::get_view(unsigned instance, std::vector<std::string> &m)
+config::get_view(unsigned instance, vector<string> &m)
 {
     lock ml(cfg_mutex);
-    get_view_wo(instance, m);
+    get_view(instance, m, ml);
 }
 
 // caller should hold cfg_mutex
 void
-config::get_view_wo(unsigned instance, std::vector<std::string> &m)
+config::get_view(unsigned instance, vector<string> &m, lock &)
 {
-    std::string value = paxos_acceptor->value(instance);
+    string value = paxos_acceptor->value(instance);
     tprintf("get_view(%d): returns %s\n", instance, value.c_str());
     members(value, m);
 }
 
 void
-config::members(const std::string &value, std::vector<std::string> &view) const
+config::members(const string &value, vector<string> &view) const
 {
-    std::istringstream ist(value);
-    std::string m;
+    istringstream ist(value);
+    string m;
     view.clear();
-    while (ist >> m) {
+    while (ist >> m)
         view.push_back(m);
-    }
 }
 
-std::string
-config::value(const std::vector<std::string> &m) const
+string
+config::value(const vector<string> &m) const
 {
-    std::ostringstream ost;
+    ostringstream ost;
     for (unsigned i = 0; i < m.size(); i++)  {
         ost << m[i];
         ost << " ";
@@ -105,14 +111,13 @@ config::value(const std::vector<std::string> &m) const
     return ost.str();
 }
 
-// caller should hold cfg_mutex
 void
-config::reconstruct()
+config::reconstruct(lock &cfg_mutex_lock)
 {
+    VERIFY(cfg_mutex_lock);
     if (paxos_acceptor->instance() > 0) {
-        std::string m;
         my_view_id = paxos_acceptor->instance();
-        get_view_wo(my_view_id, mems);
+        get_view(my_view_id, mems, cfg_mutex_lock);
         tprintf("config::reconstruct: %d %s\n",
                 my_view_id, print_members(mems).c_str());
     }
@@ -120,10 +125,9 @@ config::reconstruct()
 
 // Called by Paxos's acceptor.
 void
-config::paxos_commit(unsigned instance, const std::string &value)
+config::paxos_commit(unsigned instance, const string &value)
 {
-    std::string m;
-    std::vector<std::string> newmem;
+    vector<string> newmem;
     lock ml(cfg_mutex);
 
     members(value, newmem);
@@ -149,19 +153,19 @@ config::paxos_commit(unsigned instance, const std::string &value)
 }
 
 bool
-config::ismember(const std::string &m, unsigned vid)
+config::ismember(const string &m, unsigned vid)
 {
     lock ml(cfg_mutex);
-    std::vector<std::string> v;
-    get_view_wo(vid, v);
+    vector<string> v;
+    get_view(vid, v, ml);
     return isamember(m, v);
 }
 
 bool
-config::add(const std::string &new_m, unsigned vid)
+config::add(const string &new_m, unsigned vid)
 {
-    std::vector<std::string> m;
-    std::vector<std::string> curm;
+    vector<string> m;
+    vector<string> curm;
     lock ml(cfg_mutex);
     if (vid != my_view_id)
         return false;
@@ -169,8 +173,8 @@ config::add(const std::string &new_m, unsigned vid)
     m = mems;
     m.push_back(new_m);
     curm = mems;
-    std::string v = value(m);
-    int nextvid = my_view_id + 1;
+    string v = value(m);
+    unsigned nextvid = my_view_id + 1;
     bool r;
     {
         ml.unlock();
@@ -184,19 +188,19 @@ config::add(const std::string &new_m, unsigned vid)
 
 // caller should hold cfg_mutex
 bool
-config::remove(const std::string &m)
+config::remove(const string &m)
 {
     adopt_lock ml(cfg_mutex);
     tprintf("config::remove: my_view_id %d remove? %s\n",
             my_view_id, m.c_str());
-    std::vector<std::string> n;
+    vector<string> n;
     for (unsigned i = 0; i < mems.size(); i++) {
         if (mems[i] != m)
             n.push_back(mems[i]);
     }
-    std::string v = value(n);
-    std::vector<std::string> cmems = mems;
-    int nextvid = my_view_id + 1;
+    string v = value(n);
+    vector<string> cmems = mems;
+    unsigned nextvid = my_view_id + 1;
     bool r;
     {
         ml.unlock();
@@ -209,23 +213,23 @@ config::remove(const std::string &m)
 }
 
 void
-config::heartbeater()
+config::heartbeater() [[noreturn]]
 {
-    std::string m;
+    string m;
     heartbeat_t h;
     bool stable;
     unsigned vid;
-    std::vector<std::string> cmems;
+    vector<string> cmems;
     lock ml(cfg_mutex);
 
     while (1) {
-        auto next_timeout = std::chrono::steady_clock::now() + std::chrono::seconds(3);
+        auto next_timeout = steady_clock::now() + seconds(3);
         tprintf("heartbeater: go to sleep\n");
         config_cond.wait_until(ml, next_timeout);
 
         stable = true;
         vid = my_view_id;
-        get_view_wo(vid, cmems);
+        get_view(vid, cmems, ml);
         tprintf("heartbeater: current membership %s\n",
                 print_members(cmems).c_str());
 
@@ -265,7 +269,7 @@ config::heartbeater()
 }
 
 paxos_protocol::status
-config::heartbeat(int &r, std::string m, unsigned vid)
+config::heartbeat(int &r, string m, unsigned vid)
 {
     lock ml(cfg_mutex);
     int ret = paxos_protocol::ERR;
@@ -284,11 +288,11 @@ config::heartbeat(int &r, std::string m, unsigned vid)
 }
 
 config::heartbeat_t
-config::doheartbeat(const std::string &m)
+config::doheartbeat(const string &m)
 {
     adopt_lock ml(cfg_mutex);
     int ret = rpc_const::timeout_failure;
-    int r;
+    int r = 0;
     unsigned vid = my_view_id;
     heartbeat_t res = OK;