Remove stringref::c_str()

The expected semantics of c_str() (a null-terminated string) cannot
be satisfied with a string reference, so remove the function entirely
to prevent people from using it in buggy ways.

Replaces c_str() with data() in places where it is presumed safe,
otherwise constructs temporary string instances. Certain callsites
have been de-stringref'd in favor of regular strings, in particular
where C APIs have been transitively called. The vast majority of
these were called with string parameters anyway, so should not
cause much extra allocation.

8 files changed, 15 insertions, 13 deletions

diff --git a/vdslib/src/tests/distribution/distributiontest.cpp b/vdslib/src/tests/distribution/distributiontest.cpp
index 3090910d2bb..7af48c1904b 100644
--- a/vdslib/src/tests/distribution/distributiontest.cpp
+++ b/vdslib/src/tests/distribution/distributiontest.cpp
@@ -191,7 +191,7 @@ namespace {
             try{
                 std::vector<uint16_t> nvect;
                 distribution.getIdealNodes(nodeType, state, results[i].bucket,
-                                           nvect, upStates.c_str(), redundancy);
+                                           nvect, upStates.data(), redundancy);
                 IdealNodeList nodes;
                 for (uint32_t j=0, m=nvect.size(); j<m; ++j) {
                     nodes.push_back(Node(nodeType, nvect[j]));
diff --git a/vdslib/src/tests/distribution/grouptest.cpp b/vdslib/src/tests/distribution/grouptest.cpp
index c108a1e8a38..71d8b8bac0c 100644
--- a/vdslib/src/tests/distribution/grouptest.cpp
+++ b/vdslib/src/tests/distribution/grouptest.cpp
@@ -30,7 +30,7 @@ namespace {
         vespalib::StringTokenizer st(nodelist, ",");
         std::vector<uint16_t> nodes(st.size());
         for (uint32_t i=0; i<st.size(); ++i) {
-            nodes[i] = atoi(st[i].c_str());
+            nodes[i] = atoi(st[i].data());
         }
         group->setNodes(nodes);
         return group;
diff --git a/vdslib/src/vespa/vdslib/container/parameters.h b/vdslib/src/vespa/vdslib/container/parameters.h
index 4572b2f6f1c..ab65932496a 100644
--- a/vdslib/src/vespa/vdslib/container/parameters.h
+++ b/vdslib/src/vespa/vdslib/container/parameters.h
@@ -68,7 +68,7 @@ public:
     ParametersMap::const_iterator begin() const { return _parameters.begin(); }
     ParametersMap::const_iterator end() const { return _parameters.end(); }
     /// Convenience from earlier use.
-    void set(const KeyT & id, const vespalib::stringref & value) { _parameters[id] = Value(value.c_str(), value.size()); }
+    void set(const KeyT & id, const vespalib::stringref & value) { _parameters[id] = Value(value.data(), value.size()); }
     vespalib::stringref get(const KeyT & id, const vespalib::stringref & def = "") const;
     /**
      * Set the value identified by the id given. This requires the type to be
diff --git a/vdslib/src/vespa/vdslib/distribution/redundancygroupdistribution.cpp b/vdslib/src/vespa/vdslib/distribution/redundancygroupdistribution.cpp
index f620dc15928..99974225e9e 100644
--- a/vdslib/src/vespa/vdslib/distribution/redundancygroupdistribution.cpp
+++ b/vdslib/src/vespa/vdslib/distribution/redundancygroupdistribution.cpp
@@ -30,7 +30,7 @@ namespace {
                 firstAsterisk = i;
                 continue;
             }
-            uint32_t number = atoi(st[i].c_str());
+            uint32_t number = atoi(vespalib::string(st[i]).c_str());
             if (number <= 0 || number >= 256) {
                 throw vespalib::IllegalArgumentException(
                     "Illegal distribution spec \"" + serialized + "\". "
@@ -48,7 +48,7 @@ namespace {
         }
     }
 
-    std::vector<uint16_t> parse(vespalib::stringref& serialized) {
+    std::vector<uint16_t> parse(vespalib::stringref serialized) {
         std::vector<uint16_t> result;
         if (serialized == "") return result;
         vespalib::StringTokenizer st(serialized, "|");
diff --git a/vdslib/src/vespa/vdslib/state/clusterstate.cpp b/vdslib/src/vespa/vdslib/state/clusterstate.cpp
index fbc9943e22d..e50b18a5a82 100644
--- a/vdslib/src/vespa/vdslib/state/clusterstate.cpp
+++ b/vdslib/src/vespa/vdslib/state/clusterstate.cpp
@@ -88,7 +88,7 @@ ClusterState::ClusterState(const vespalib::string& serialized)
         if (key.empty() || ! parse(key, value, nodeData) ) {
             LOG(debug, "Unknown key %s in systemstate. Ignoring it, assuming it's "
                        "a new feature from a newer version than ourself: %s",
-                       key.c_str(), serialized.c_str());
+                       vespalib::string(key).c_str(), serialized.c_str());
         }
     }
     nodeData.addTo(_nodeStates, _nodeCount);
@@ -106,13 +106,13 @@ ClusterState::parse(vespalib::stringref key, vespalib::stringref value, NodeData
         break;
     case 'b':
         if (key == "bits") {
-            _distributionBits = atoi(value.c_str());
+            _distributionBits = atoi(value.data());
             return true;
         }
         break;
     case 'v':
         if (key == "version") {
-            _version = atoi(value.c_str());
+            _version = atoi(value.data());
             return true;
         }
         break;
@@ -145,7 +145,7 @@ ClusterState::parseSorD(vespalib::stringref key, vespalib::stringref value, Node
     if (nodeType == 0) return false;
     if (dot == vespalib::string::npos) { // Entry that set node counts
         uint16_t nodeCount = 0;
-        nodeCount = atoi(value.c_str());
+        nodeCount = atoi(value.data());
 
         if (nodeCount > _nodeCount[*nodeType] ) {
             _nodeCount[*nodeType] = nodeCount;
@@ -155,9 +155,9 @@ ClusterState::parseSorD(vespalib::stringref key, vespalib::stringref value, Node
     vespalib::string::size_type dot2 = key.find('.', dot + 1);
     Node node;
     if (dot2 == vespalib::string::npos) {
-        node = Node(*nodeType, atoi(key.substr(dot + 1).c_str()));
+        node = Node(*nodeType, atoi(key.substr(dot + 1).data()));
     } else {
-        node = Node(*nodeType, atoi(key.substr(dot + 1, dot2 - dot - 1).c_str()));
+        node = Node(*nodeType, atoi(key.substr(dot + 1, dot2 - dot - 1).data()));
     }
 
     if (node.getIndex() >= _nodeCount[*nodeType]) {
diff --git a/vdslib/src/vespa/vdslib/state/clusterstate.h b/vdslib/src/vespa/vdslib/state/clusterstate.h
index 9e8dd0f292a..26c6f1b95ef 100644
--- a/vdslib/src/vespa/vdslib/state/clusterstate.h
+++ b/vdslib/src/vespa/vdslib/state/clusterstate.h
@@ -72,7 +72,9 @@ public:
                              const std::string& indent = "") const;
 
 private:
+    // Preconditions: `key` and `value` MUST point into null-terminated strings.
     bool parse(vespalib::stringref key, vespalib::stringref value, NodeData & nodeData);
+    // Preconditions: `key` and `value` MUST point into null-terminated strings.
     bool parseSorD(vespalib::stringref key, vespalib::stringref value, NodeData & nodeData);
     void removeExtraElements();
     void printStateGroupwise(std::ostream& out, const Group&, bool verbose,
diff --git a/vdslib/src/vespa/vdslib/state/diskstate.cpp b/vdslib/src/vespa/vdslib/state/diskstate.cpp
index bcc380e0d75..c963dacff82 100644
--- a/vdslib/src/vespa/vdslib/state/diskstate.cpp
+++ b/vdslib/src/vespa/vdslib/state/diskstate.cpp
@@ -73,7 +73,7 @@ DiskState::DiskState(const vespalib::stringref & serialized)
         }
         LOG(debug, "Unknown key %s in diskstate. Ignoring it, assuming it's a "
                    "new feature from a newer version than ourself: %s",
-            key.c_str(), serialized.c_str());
+            key.c_str(), vespalib::string(serialized).c_str());
     }
 
 }
diff --git a/vdslib/src/vespa/vdslib/state/nodestate.cpp b/vdslib/src/vespa/vdslib/state/nodestate.cpp
index ff6c8f31c89..d59686dcb1c 100644
--- a/vdslib/src/vespa/vdslib/state/nodestate.cpp
+++ b/vdslib/src/vespa/vdslib/state/nodestate.cpp
@@ -229,7 +229,7 @@ NodeState::NodeState(const vespalib::stringref & serialized, const NodeType* typ
         }
         LOG(debug, "Unknown key %s in nodestate. Ignoring it, assuming it's a "
                    "new feature from a newer version than ourself: %s",
-            key.c_str(), serialized.c_str());
+            key.c_str(), vespalib::string(serialized).c_str());
     }
     diskData.addTo(_diskStates);
     updateAnyDiskDownFlag();