roughly 10-fold speedup in navcat, plus fix ordering bug

navcat.cc

@@ -98,14 +98,14 @@ static size_t writen2(int fd, const void *buf, size_t count)
 
 void sendProtobuf(string_view dir, time_t startTime, time_t stopTime=0)
 {
-  pair<uint64_t, uint64_t> start = {startTime, 0};
+  pair<int64_t, int64_t> start(startTime, 0);
 
   // so we have a ton of files, and internally these are not ordered
   map<string,uint32_t> fpos;
-  vector<NavMonMessage> nmms;
+  vector<pair<timespec,string> > rnmms;
   for(;;) {
     auto srcs = getSources(dir);
-    nmms.clear();
+    rnmms.clear();
     for(const auto& src: srcs) {
       string fname = getPath(dir, start.first, src);
       FILE* fp = fopen(fname.c_str(), "r");
@@ -118,36 +118,35 @@ void sendProtobuf(string_view dir, time_t startTime, time_t stopTime=0)
         continue;
       }
       cerr <<"Seeked to position "<<fpos[fname]<<" of "<<fname<<endl;
-      NavMonMessage nmm;
 
       uint32_t looked=0;
-      while(getNMM(fp, nmm, offset)) {
+      string msg;
+      struct timespec ts;
+      while(getRawNMM(fp, ts, msg, offset)) {
         // don't drop data that is only 5 seconds too old
-        if(make_pair(nmm.localutcseconds() + 5, nmm.localutcnanoseconds()) >= start) {
-          nmms.push_back(nmm);
+        if(make_pair(ts.tv_sec + 5, ts.tv_nsec) >= start) {
+          rnmms.push_back({ts, msg});
         }
         ++looked;
       }
-      cerr<<"Harvested "<<nmms.size()<<" events out of "<<looked<<endl;
+      cerr<<"Harvested "<<rnmms.size()<<" events out of "<<looked<<endl;
       fpos[fname]=offset;
       fclose(fp);
     }
 
-    sort(nmms.begin(), nmms.end(), [](const auto& a, const auto& b)
+    sort(rnmms.begin(), rnmms.end(), [](const auto& a, const auto& b)
          {
-           return make_pair(a.localutcseconds(), b.localutcnanoseconds()) <
-             make_pair(b.localutcseconds(), b.localutcnanoseconds());
+           return std::tie(a.first.tv_sec, a.first.tv_nsec)
+                < std::tie(b.first.tv_sec, b.first.tv_nsec);
          });
 
-    for(const auto& nmm: nmms) {
-      if(nmm.localutcseconds() > stopTime)
+    for(const auto& nmm: rnmms) {
+      if(nmm.first.tv_sec > stopTime)
         break;
-      std::string out;
-      nmm.SerializeToString(&out);
       std::string buf="bert";
-      uint16_t len = htons(out.size());
+      uint16_t len = htons(nmm.second.size());
       buf.append((char*)(&len), 2);
-      buf+=out;
+      buf += nmm.second;
       //fwrite(buf.c_str(), 1, buf.size(), stdout);
       writen2(1, buf.c_str(), buf.size());
     }

storage.cc

@@ -78,3 +78,27 @@ bool getNMM(FILE* fp, NavMonMessage& nmm, uint32_t& offset)
   offset += 4 + 2 + len;
   return true;
 }
+
+
+bool getRawNMM(FILE* fp, timespec& t, string& raw, uint32_t& offset)
+{
+  char bert[4];
+  if(fread(bert, 1, 4, fp) != 4 || bert[0]!='b' || bert[1]!='e' || bert[2] !='r' || bert[3]!='t') {
+    return false;
+  }
+    
+  uint16_t len;
+  if(fread(&len, 1, 2, fp) != 2)
+    return false;
+  len = htons(len);
+  char buffer[len];
+  if(fread(buffer, 1, len, fp) != len)
+    return false;
+  NavMonMessage nmm;
+  raw.assign(buffer, len);
+  nmm.ParseFromString(raw);
+  t.tv_sec = nmm.localutcseconds();
+  t.tv_nsec = nmm.localutcnanoseconds();
+  offset += 4 + 2 + len;
+  return true;
+}

storage.hh

@@ -8,3 +8,4 @@ std::vector<std::string> getPathComponents(std::string_view root, time_t s, uint
 std::string getPath(std::string_view root, time_t s, uint64_t sourceid, bool create=false);
 bool getNMM(int fd, NavMonMessage& nmm, uint32_t& offset);
 bool getNMM(FILE* fp, NavMonMessage& nmm, uint32_t& offset);
+bool getRawNMM(FILE* fp, timespec& t, std::string& raw, uint32_t& offset);