get rid of numerous probably inocuous valgrind/helgrind messages by ensuring that actual string copies are passed between threads, without refcount/shared data magic

src/utils/idfile.cpp

@@ -30,6 +30,18 @@
 using namespace std;
 #endif /* NO_NAMESPACES */
 
+// Bogus code to avoid bogus valgrind mt warnings about the
+// initialization of treat_mbox_...  which I can't even remember the
+// use of (it's not documented or ever set)
+static int treat_mbox_as_rfc822;
+class InitTMAR {
+public:
+    InitTMAR() {
+        treat_mbox_as_rfc822 = getenv("RECOLL_TREAT_MBOX_AS_RFC822") ? 1 : -1;
+    }
+};
+static InitTMAR initTM;
+
 /** 
  * This code is currently ONLY used to identify mbox and mail message files
  * which are badly handled by standard mime type identifiers
@@ -49,11 +61,6 @@ const int wantnhead = 3;
 // fn is for message printing
 static string idFileInternal(istream& input, const char *fn)
 {
-    static int treat_mbox_as_rfc822;
-    if (treat_mbox_as_rfc822 == 0) {
-	treat_mbox_as_rfc822 = getenv("RECOLL_TREAT_MBOX_AS_RFC822") ? 1 : -1;
-    }
-
     bool line1HasFrom = false;
     bool gotnonempty = false;
     int lookslikemail = 0;

src/utils/smallut.cpp

@@ -42,6 +42,16 @@ using namespace std;
 #include "hldata.h"
 #include "cstr.h"
 
+void map_ss_cp_noshr(const map<string,string> s, map<string,string> *d)
+{
+    for (map<string,string>::const_iterator it= s.begin();
+         it != s.end(); it++) {
+        d->insert(
+            pair<string,string>(string(it->first.begin(), it->first.end()),
+                                string(it->second.begin(), it->second.end())));
+    }
+}
+
 int stringicmp(const string & s1, const string& s2) 
 {
     string::const_iterator it1 = s1.begin();

src/utils/smallut.h

@@ -197,6 +197,11 @@ inline void leftzeropad(string& s, unsigned len)
 	s = s.insert(0, len - s.length(), '0');
 }
 
+// Duplicate map<string,string> while ensuring no shared string data (to pass
+// to other thread):
+void map_ss_cp_noshr(const std::map<std::string,std::string> s,
+                      std::map<std::string,std::string> *d);
+
 // Code for static initialization of an stl map. Somewhat like Boost.assign. 
 // Ref: http://stackoverflow.com/questions/138600/initializing-a-static-stdmapint-int-in-c
 // Example use: map<int, int> m = create_map<int, int> (1,2) (3,4) (5,6) (7,8);