Add config option to redirect external helpers error output to a file

src/internfile/mh_exec.cpp

@@ -162,7 +162,11 @@ bool MimeHandlerExec::next_document()
     mexec.putenv(m_forPreview ? "RECOLL_FILTER_FORPREVIEW=yes" :
                  "RECOLL_FILTER_FORPREVIEW=no");
     mexec.setrlimit_as(m_filtermaxmbytes);
-
+    std::string errfile;
+    m_config->getConfParam("helperlogfilename", errfile);
+    if (!errfile.empty()) {
+        mexec.setStderr(errfile);
+    }
     int status;
     try {
         status = mexec.doexec(cmd, myparams, 0, &output);

src/internfile/mh_execm.cpp

@@ -63,6 +63,11 @@ bool MimeHandlerExecMultiple::startCmd()
     m_cmd.setrlimit_as(m_filtermaxmbytes);
     m_adv.setmaxsecs(m_filtermaxseconds);
     m_cmd.setAdvise(&m_adv);
+    std::string errfile;
+    m_config->getConfParam("helperlogfilename", errfile);
+    if (!errfile.empty()) {
+        m_cmd.setStderr(errfile);
+    }
 
     // Build parameter list: delete cmd name
     vector<string>myparams(params.begin() + 1, params.end());

src/sampleconf/recoll.conf

@@ -660,6 +660,17 @@ logfilename = stderr
 # <brief>Override logfilename for the indexer.</brief><descr></descr></var>
 #idxlogfilename = stderr
 
+# <var name="helperlogfilename" type="fn">
+#
+# <brief>Destination file for external helpers standard error
+# output.</brief>
+#
+# <descr>The external program error output is left alone by default,
+# e.g. going to the terminal when the recoll[index] program is executed
+# from the command line. Use /dev/null or a file inside a non-existent
+# directory to completely suppress the output.</brief></var>
+#helperlogfilename=
+
 # <var name="daemloglevel" type="int">
 #
 # <brief>Override loglevel for the indexer in real time

src/utils/workqueue.h

@@ -168,7 +168,7 @@ public:
     bool waitIdle() {
         std::unique_lock<std::mutex> lock(m_mutex);
         if (!ok()) {
-            LOGERR("WorkQueue::waitIdle:"  << m_name << ": not ok\n");
+            LOGINF("WorkQueue::waitIdle:"  << m_name << ": queue already closed\n");
             return false;
         }