From 665e12562a4aa4f40aeeed0cfd207b49f89c9fd1 Mon Sep 17 00:00:00 2001
From: "Frank Ch. Eigler" <fche@elastic.org>
Date: Wed, 8 Jul 2009 13:04:10 -0400
Subject: PR3498 cont'd, fix wildcard module("*") probes

* dwflpp.cxx (name_has_wildcard): Make static.
  (dwfl_report_offline_predicate): Check & adjust behavior.
* dwflpp.h: Corresponding changes.
* tapsets.cxx: Note that kern_dw[] keys may be wildcard strings.
* testsuite/buildok/fortysix.stp: New test.
---
 dwflpp.cxx                     | 44 +++++++++++++++++++++---------------------
 dwflpp.h                       |  2 +-
 tapsets.cxx                    |  2 +-
 testsuite/buildok/fortysix.stp |  3 +++
 4 files changed, 27 insertions(+), 24 deletions(-)
 create mode 100755 testsuite/buildok/fortysix.stp

diff --git a/dwflpp.cxx b/dwflpp.cxx
index 17bce608..531d413e 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -205,7 +205,7 @@ dwflpp::module_name_matches(const string& pattern)
 
 
 bool
-dwflpp::name_has_wildcard(const string& pattern)
+dwflpp::name_has_wildcard (const string& pattern)
 {
   return (pattern.find('*') != string::npos ||
           pattern.find('?') != string::npos ||
@@ -258,19 +258,30 @@ static int dwfl_report_offline_predicate (const char* modname, const char* filen
   if (pending_interrupts)
     return -1;
 
-  if (offline_search_match_p)
-    return -1;
-
   assert (offline_search_modname);
 
-  /* Reject mismatching module names */
-  if (strcmp(modname, offline_search_modname))
-    return 0;
-  else
-    {
+  if (dwflpp::name_has_wildcard (offline_search_modname)) {
+    int match_p = !fnmatch(offline_search_modname, modname, 0);
+    // In the wildcard case, we don't short-circuit (return -1) upon 
+    // offline_search_match_p, analogously to dwflpp::module_name_final_match().
+
+    if (match_p) 
       offline_search_match_p ++;
-      return 1;
-    }
+
+    return match_p;
+  } else { /* non-wildcard mode */
+    if (offline_search_match_p)
+      return -1;
+
+    /* Reject mismatching module names */
+    if (strcmp(modname, offline_search_modname))
+      return 0;
+    else
+      {
+        offline_search_match_p ++;
+        return 1;
+      }
+  }
 }
 
 
@@ -339,17 +350,6 @@ dwflpp::setup_kernel(const string& name, bool debuginfo_needed)
                             sess.kernel_build_tree + string("'"));
     }
 
-  // XXX: it would be nice if we could do a single
-  // ..._report_offline call for an entire systemtap script, so
-  // that a selection predicate would filter out modules outside
-  // the union of all the requested wildcards.  But we build
-  // derived_probes one-by-one and we don't have lookahead.
-  // PR 3498.
-
-  // XXX: a special case: if we have only kernel.* probe points,
-  // we shouldn't waste time looking for module debug-info (and
-  // vice versa).
-
   // NB: the result of an _offline call is the assignment of
   // virtualized addresses to relocatable objects such as
   // modules.  These have to be converted to real addresses at
diff --git a/dwflpp.h b/dwflpp.h
index d6d97cd0..e0098b9b 100644
--- a/dwflpp.h
+++ b/dwflpp.h
@@ -178,7 +178,7 @@ struct dwflpp
   Dwarf_Die *query_cu_containing_address(Dwarf_Addr a);
 
   bool module_name_matches(const std::string& pattern);
-  bool name_has_wildcard(const std::string& pattern);
+  static bool name_has_wildcard(const std::string& pattern);
   bool module_name_final_match(const std::string& pattern);
 
   bool function_name_matches_pattern(const std::string& name, const std::string& pattern);
diff --git a/tapsets.cxx b/tapsets.cxx
index 4988b7e7..aecdca61 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -589,7 +589,7 @@ struct dwarf_query : public base_query
 
 struct dwarf_builder: public derived_probe_builder
 {
-  map <string,dwflpp*> kern_dw;
+  map <string,dwflpp*> kern_dw; /* NB: key string could be a wildcard */
   map <string,dwflpp*> user_dw;
   dwarf_builder() {}
 
diff --git a/testsuite/buildok/fortysix.stp b/testsuite/buildok/fortysix.stp
new file mode 100755
index 00000000..013ca5bc
--- /dev/null
+++ b/testsuite/buildok/fortysix.stp
@@ -0,0 +1,3 @@
+#! stap -p4
+// PR 3498 + wildcarded modules
+probe module("*scsi*").function("*").call { }
-- 
cgit