Merge branch 'devel' of ssh://github.com/ArangoDB/ArangoDB into devel

Documentation/Books/Users/IndexHandling/README.mdpp

@@ -4,6 +4,8 @@ This is an introduction to ArangoDB's interface for indexes in general.
 There are special sections for 
 
 - [index basics](../IndexHandling/IndexBasics.md) 
+- [Which Index to use when](../IndexHandling/WhichIndex.md)
+- [How ArangoDB uses indexes](../IndexHandling/HowArangoDBUsesIndexes.md)
 - [working with indexes](../IndexHandling/WorkingWithIndexes.md) 
  - [hash indexes](../IndexHandling/Hash.md)
  - [skiplists](../IndexHandling/Skiplist.md)

arangod/Cluster/ClusterInfo.h

@@ -72,7 +72,7 @@ namespace triagens {
 
         CollectionInfo ();
 
-        CollectionInfo (struct TRI_json_t*);
+        explicit CollectionInfo (struct TRI_json_t*);
 
         CollectionInfo (CollectionInfo const&);
 

arangod/Cluster/ClusterTraverser.cpp

@@ -181,7 +181,14 @@ void ClusterTraverser::EdgeGetter::operator() (std::string const& startVertex,
       if (_traverser->_vertices.find(toId) == _traverser->_vertices.end()) {
         verticesToFetch.emplace(toId);
       }
-      _traverser->_edges.emplace(edgeId, edge.copy().steal());
+      std::unique_ptr<TRI_json_t> copy(edge.copy().steal());
+      if (copy != nullptr) {
+        if (_traverser->_edges.emplace(edgeId, copy.get()).second) {
+          // if insertion was successful, hand over the ownership
+          copy.release();
+        }
+        // else we have a duplicate and we need to free the copy again
+      }
     }
 
     std::vector<TraverserExpression*> expVertices;

js/server/modules/@arangodb/testing.js

@@ -518,6 +518,20 @@ function readImportantLogLines(logPath) {
 }
 
 function analyzeCoreDump(instanceInfo, options, storeArangodPath, pid) {
+/* 
+ * We assume the system has core files in /var/tmp/, and we have a gdb.
+ * you can do this at runtime doing:
+ *
+ * echo 1 > /proc/sys/kernel/core_uses_pid
+ * echo /var/tmp/core-%e-%p-%t > /proc/sys/kernel/core_pattern
+ *
+ * or at system startup by altering /etc/sysctl.d/corepattern.conf : 
+ * # We want core files to be located in a central location
+ * # and know the PID plus the process name for later use.
+ * kernel.core_uses_pid = 1
+ * kernel.core_pattern =  /var/tmp/core-%e-%p-%t
+ */
+
   var command;
   command  = '(';
   command += "printf 'bt full\\n thread apply all bt\\n';";

lib/Basics/operating-system.h

@@ -734,7 +734,7 @@ typedef unsigned char bool;
 #define S_IRGRP _S_IREAD
 #define S_IWGRP _S_IWRITE
 
-#define TRI_O_CLOEXEC 
+#define TRI_O_CLOEXEC                   0 
 
 #define O_RDONLY                        _O_RDONLY
 #define TRI_CHDIR                       _chdir