From 3c4ac46872af5d6c59b22361898f935c39ec0be9 Mon Sep 17 00:00:00 2001
From: Felix Lu <flu@redhat.com>
Date: Tue, 9 Aug 2016 15:36:14 -0400
Subject: [PATCH] filename based auto path tapset support

Sometimes the process name may change with new versions and the
tapset must be modified. Process probe points in the PATH directory
may now have their arguments replaced by the full file path starting
from /PATH.

* parse.cxx: Pass alias_seen flag to parse_probe_points(). Add filepath
  argument to process component.
---
 parse.cxx | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/parse.cxx b/parse.cxx
index a5ff20f5f..1a5ba4cc2 100644
--- a/parse.cxx
+++ b/parse.cxx
@@ -179,9 +179,9 @@ private: // nonterminals
   void do_parse_functiondecl (vector<functiondecl*>&, const token*,
                               string const&, bool);
   embeddedcode* parse_embeddedcode ();
-  vector<probe_point*> parse_probe_points ();
-  vector<probe_point*> parse_components ();
-  vector<probe_point*> parse_component ();
+  vector<probe_point*> parse_probe_points (bool alias_seen);
+  vector<probe_point*> parse_components (bool alias_seen);
+  vector<probe_point*> parse_component (bool alias_seen);
   literal_string* consume_string_literals (const token*);
   literal_string* parse_literal_string ();
   literal* parse_literal ();
@@ -2030,10 +2030,11 @@ parser::parse_probe (vector<probe *> & probe_ret,
   vector<probe_point *> locations;
 
   int epilogue_alias = 0;
+  bool alias_seen = false;
 
   while (1)
     {
-      vector<probe_point*> pps = parse_probe_points();
+      vector<probe_point*> pps = parse_probe_points(alias_seen);
 
       const token* t = peek ();
       if (pps.size() == 1 && t
@@ -2042,6 +2043,7 @@ parser::parse_probe (vector<probe *> & probe_ret,
           if (pps[0]->optional || pps[0]->sufficient)
             throw PARSE_ERROR (_("probe point alias name cannot be optional nor sufficient"), pps[0]->components.front()->tok);
           aliases.push_back(pps[0]);
+          alias_seen = true;
           swallow ();
           continue;
         }
@@ -2052,6 +2054,7 @@ parser::parse_probe (vector<probe *> & probe_ret,
             throw PARSE_ERROR (_("probe point alias name cannot be optional nor sufficient"), pps[0]->components.front()->tok);
           aliases.push_back(pps[0]);
           epilogue_alias = 1;
+          alias_seen = true;
           swallow ();
           continue;
         }
@@ -2476,12 +2479,12 @@ parser::do_parse_functiondecl (vector<functiondecl*>& functions, const token* t,
 }
 
 vector<probe_point*>
-parser::parse_probe_points()
+parser::parse_probe_points(bool alias_seen)
 {
   vector<probe_point*> pps;
   while (1)
     {
-      vector<probe_point*> tail = parse_components();
+      vector<probe_point*> tail = parse_components(alias_seen);
       pps.insert(pps.end(), tail.begin(), tail.end());
 
       const token* t = peek();
@@ -2502,12 +2505,12 @@ parser::parse_probe_points()
 }
 
 vector<probe_point*>
-parser::parse_components()
+parser::parse_components(bool alias_seen)
 {
   vector<probe_point*> pps;
   while (1)
     {
-      vector<probe_point*> suffix = parse_component();
+      vector<probe_point*> suffix = parse_component(alias_seen);
 
       // Cartesian product of components
       if (pps.empty())
@@ -2593,7 +2596,7 @@ parser::parse_components()
 }
 
 vector<probe_point*>
-parser::parse_component()
+parser::parse_component(bool alias_seen)
 {
   const token* t = next ();
   if (! (t->type == tok_identifier
@@ -2606,7 +2609,7 @@ parser::parse_component()
   if (t && t->type == tok_operator && t->content == "{")
     {
       swallow();
-      vector<probe_point*> pps = parse_probe_points();
+      vector<probe_point*> pps = parse_probe_points(alias_seen);
       t = peek();
       if (!(t && t->type == tok_operator && t->content == "}"))
         throw PARSE_ERROR (_("expected '}'"));
@@ -2685,6 +2688,16 @@ parser::parse_component()
             throw PARSE_ERROR (_("expected ')'"));
           swallow ();
         }
+      else if (alias_seen && auto_path && c->functor == "process")
+        {
+          // PATH expansion of process component without argument.
+          // The filename without the .stp extension is used.
+          string::size_type start = input_name.find("PATH/") + 4;
+          string::size_type end = input_name.rfind(".stp");
+          string path = input_name.substr(start, end - start);
+          c->arg = new literal_string(path);
+        }
+
       return pps;
     }
 }
-- 
2.43.5