Return hash module values directly as strings

* session.h (systemtap_session): remove tracequery_path
* hash.cxx (find_tracequery_hash, find_typequery_hash): return strings
* tapsets.cxx (dwarf_cast_expanding_visitor::filter_special_modules):
  get the hashed path from the return value instead of a parameter
  (tracepoint_builder::init_dw): ditto, and don't stuff it in session

4 files changed, 19 insertions, 20 deletions

diff --git a/hash.cxx b/hash.cxx
index 45ae05eb..e550be76 100644
--- a/hash.cxx
+++ b/hash.cxx
@@ -256,7 +256,7 @@ find_hash (systemtap_session& s, const string& script)
 }
 
 
-void
+string
 find_tracequery_hash (systemtap_session& s)
 {
   hash h;
@@ -268,14 +268,14 @@ find_tracequery_hash (systemtap_session& s)
   string result, hashdir;
   h.result(result);
   if (!create_hashdir(s, result, hashdir))
-    return;
+    return "";
 
-  s.tracequery_path = hashdir + "/tracequery_" + result + ".ko";
+  return hashdir + "/tracequery_" + result + ".ko";
 }
 
 
-void
-find_typequery_hash (systemtap_session& s, const string& name, string& module)
+string
+find_typequery_hash (systemtap_session& s, const string& name)
 {
   hash h;
   get_base_hash(s, h);
@@ -287,9 +287,9 @@ find_typequery_hash (systemtap_session& s, const string& name, string& module)
   string result, hashdir;
   h.result(result);
   if (!create_hashdir(s, result, hashdir))
-    return;
+    return "";
 
-  module = hashdir + "/typequery_" + result
+  return hashdir + "/typequery_" + result
     + (name[0] == 'k' ? ".ko" : ".so");
 }
 
diff --git a/hash.h b/hash.h
index 7e432216..a6397a52 100644
--- a/hash.h
+++ b/hash.h
@@ -36,8 +36,7 @@ public:
 };
 
 void find_hash (systemtap_session& s, const std::string& script);
-void find_tracequery_hash (systemtap_session& s);
-void find_typequery_hash (systemtap_session& s, const std::string& name,
-                          std::string& module);
+std::string find_tracequery_hash (systemtap_session& s);
+std::string find_typequery_hash (systemtap_session& s, const std::string& name);
 
 /* vim: set sw=2 ts=8 cino=>4,n-2,{2,^-2,t0,(0,u0,w1,M1 : */
diff --git a/session.h b/session.h
index a617e47f..e68cd6df 100644
--- a/session.h
+++ b/session.h
@@ -124,7 +124,6 @@ struct systemtap_session
   std::string cache_path;
   std::string hash_path;
   std::string stapconf_path;
-  std::string tracequery_path;
 
   // dwarfless operation
   bool consult_symtab;
diff --git a/tapsets.cxx b/tapsets.cxx
index 83f35e17..bb6f0daa 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -2645,7 +2645,7 @@ void dwarf_cast_expanding_visitor::filter_special_modules(string& module)
       if (s.use_cache)
         {
           // see if the cached module exists
-          find_typequery_hash(s, module, cached_module);
+          cached_module = find_typequery_hash(s, module);
           if (!cached_module.empty())
             {
               int fd = open(cached_module.c_str(), O_RDONLY);
@@ -5697,19 +5697,20 @@ tracepoint_builder::init_dw(systemtap_session& s)
   if (dw != NULL)
     return true;
 
+  string tracequery_path;
   if (s.use_cache)
     {
       // see if the cached module exists
-      find_tracequery_hash(s);
-      if (!s.tracequery_path.empty())
+      tracequery_path = find_tracequery_hash(s);
+      if (!tracequery_path.empty())
         {
-          int fd = open(s.tracequery_path.c_str(), O_RDONLY);
+          int fd = open(tracequery_path.c_str(), O_RDONLY);
           if (fd != -1)
             {
               if (s.verbose > 2)
-                clog << "Pass 2: using cached " << s.tracequery_path << endl;
+                clog << "Pass 2: using cached " << tracequery_path << endl;
 
-              dw = new dwflpp(s, s.tracequery_path, false);
+              dw = new dwflpp(s, tracequery_path, false);
               close(fd);
               return true;
             }
@@ -5727,11 +5728,11 @@ tracepoint_builder::init_dw(systemtap_session& s)
       // try to save tracequery in the cache
       if (s.verbose > 2)
         clog << "Copying " << tracequery_ko
-             << " to " << s.tracequery_path << endl;
+             << " to " << tracequery_path << endl;
       if (copy_file(tracequery_ko.c_str(),
-                    s.tracequery_path.c_str()) != 0)
+                    tracequery_path.c_str()) != 0)
         cerr << "Copy failed (\"" << tracequery_ko << "\" to \""
-             << s.tracequery_path << "\"): " << strerror(errno) << endl;
+             << tracequery_path << "\"): " << strerror(errno) << endl;
     }
 
   dw = new dwflpp(s, tracequery_ko, false);