Fix segfault when using Python's -threads options and exceptions are thrown

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@11980 626c5289-ae23-0410-ae9c-e8d60b6d4f22

CHANGES.current

@@ -1,6 +1,10 @@
 Version 2.0.0 (in progress)
 ============================
 
+2010-04-03: wsfulton
+            [Python] Fix exceptions being thrown with the -threads option based on patch from Arto Vuori.
+            Fixes bug #2818499.
+
 2010-04-03: wsfulton
             Fix Makefile targets: distclean and maintainer-clean
 

Examples/test-suite/common.mk

@@ -375,6 +375,7 @@ CPP_TEST_CASES += \
 	template_virtual \
 	template_whitespace \
 	threads \
+	threads_exception \
 	throw_exception \
 	typedef_array_member \
 	typedef_class \

Examples/test-suite/python/threads_exception_runme.py

@@ -0,0 +1,36 @@
+import threads_exception
+
+t = threads_exception.Test()
+try:
+  t.unknown()
+except RuntimeError,e:
+  pass
+
+try:
+  t.simple()
+except RuntimeError,e:
+  if e.args[0] != 37:
+    raise RuntimeError
+
+try:
+  t.message()
+except RuntimeError,e:
+  if e.args[0] != "I died.":
+    raise RuntimeError
+
+try:
+  t.hosed()
+except threads_exception.Exc,e:
+  if e.code != 42:
+    raise RuntimeError
+  if e.msg != "Hosed":
+    raise RuntimeError
+
+for i in range(1,4):
+  try:
+    t.multi(i)
+  except RuntimeError,e:
+    pass
+  except threads_exception.Exc,e:
+    pass
+

Examples/test-suite/threads_exception.i

@@ -0,0 +1,54 @@
+// Throw a lot of exceptions
+
+// The Python runtime tests were previously failing with the -threads option on Windows due to SWIG_PYTHON_THREAD_BEGIN_ALLOW not being within the try block.
+
+%module(threads="1") threads_exception
+
+%{
+struct A {};
+%}
+
+%inline %{
+#include <string>
+
+#if defined(_MSC_VER)
+  #pragma warning(disable: 4290) // C++ exception specification ignored except to indicate a function is not __declspec(nothrow)
+#endif
+
+class Exc {
+public:
+  Exc(int c, const char *m) {
+    code = c;
+    strncpy(msg,m,255);
+  }
+  int code;
+  char msg[256];
+};
+
+class Test {
+public:
+  int simple() throw(int) {
+      throw(37);
+      return 1;
+  }
+  int message() throw(const char *) {
+      throw("I died.");
+      return 1;
+  }
+  int hosed() throw(Exc) {
+      throw(Exc(42,"Hosed"));
+      return 1;
+  } 
+  int unknown() throw(A*) {
+      static A a;
+      throw &a;
+      return 1;
+  }
+  int multi(int x) throw(int, const char *, Exc) {
+     if (x == 1) throw(37);
+     if (x == 2) throw("Bleah!");
+     if (x == 3) throw(Exc(42,"No-go-diggy-die"));
+     return 1;
+  }
+};
+%}

Source/Modules/emit.cxx

@@ -462,32 +462,40 @@ String *emit_action(Node *n) {
     Printf(eaction, "try {\n");
   }
 
+  String *preaction = Getattr(n, "wrap:preaction");
+  if (preaction)
+    Printv(eaction, preaction, NIL);
+
   Printv(eaction, action, NIL);
 
+  String *postaction = Getattr(n, "wrap:postaction");
+  if (postaction)
+    Printv(eaction, postaction, NIL);
+
   if (catchlist) {
     int unknown_catch = 0;
     Printf(eaction, "}\n");
     for (Parm *ep = catchlist; ep; ep = nextSibling(ep)) {
       String *em = Swig_typemap_lookup("throws", ep, "_e", 0);
       if (em) {
-	SwigType *et = Getattr(ep, "type");
-	SwigType *etr = SwigType_typedef_resolve_all(et);
-	if (SwigType_isreference(etr) || SwigType_ispointer(etr) || SwigType_isarray(etr)) {
-	  Printf(eaction, "catch(%s) {", SwigType_str(et, "_e"));
-	} else if (SwigType_isvarargs(etr)) {
-	  Printf(eaction, "catch(...) {");
-	} else {
-	  Printf(eaction, "catch(%s) {", SwigType_str(et, "&_e"));
-	}
-	Printv(eaction, em, "\n", NIL);
-	Printf(eaction, "}\n");
+        SwigType *et = Getattr(ep, "type");
+        SwigType *etr = SwigType_typedef_resolve_all(et);
+        if (SwigType_isreference(etr) || SwigType_ispointer(etr) || SwigType_isarray(etr)) {
+          Printf(eaction, "catch(%s) {", SwigType_str(et, "_e"));
+        } else if (SwigType_isvarargs(etr)) {
+          Printf(eaction, "catch(...) {");
+        } else {
+          Printf(eaction, "catch(%s) {", SwigType_str(et, "&_e"));
+        }
+        Printv(eaction, em, "\n", NIL);
+        Printf(eaction, "}\n");
       } else {
 	Swig_warning(WARN_TYPEMAP_THROW, Getfile(n), Getline(n), "No 'throws' typemap defined for exception type '%s'\n", SwigType_str(Getattr(ep, "type"), 0));
-	unknown_catch = 1;
+        unknown_catch = 1;
       }
     }
     if (unknown_catch) {
-      Printf(eaction, "catch(...) { throw; }\n");
+    Printf(eaction, "catch(...) { throw; }\n");
     }
   }
 

Source/Modules/python.cxx

@@ -211,6 +211,7 @@ public:
   virtual void thread_begin_allow(Node *n, String *f) {
     if (!GetFlag(n, "feature:nothreadallow")) {
       String *bb = Getattr(n, "feature:threadbeginallow");
+      Append(f, "{\n");
       if (bb) {
 	Append(f, bb);
       } else {
@@ -222,11 +223,13 @@ public:
   virtual void thread_end_allow(Node *n, String *f) {
     if (!GetFlag(n, "feature:nothreadallow")) {
       String *eb = Getattr(n, "feature:threadendallow");
+      Append(f, "\n");
       if (eb) {
 	Append(f, eb);
       } else {
-	Append(f, "SWIG_PYTHON_THREAD_END_ALLOW;\n");
+	Append(f, "SWIG_PYTHON_THREAD_END_ALLOW;");
       }
+      Append(f, "\n}");
     }
   }
 
@@ -2200,8 +2203,13 @@ public:
       Append(f->code, "try {\n");
     } else {
       if (allow_thread) {
-	Append(f->code, "{\n");
-	thread_begin_allow(n, f->code);
+	String *preaction = NewString("");
+	thread_begin_allow(n, preaction);
+	Setattr(n,"wrap:preaction", preaction);
+
+	String *postaction = NewString("");
+	thread_end_allow(n, postaction);
+	Setattr(n,"wrap:postaction", postaction);
       }
     }
 
@@ -2214,11 +2222,6 @@ public:
       Append(actioncode, "} catch (Swig::DirectorException&) {\n");
       Append(actioncode, "  SWIG_fail;\n");
       Append(actioncode, "}\n");
-    } else {
-      if (allow_thread) {
-	thread_end_allow(n, actioncode);
-	Append(actioncode, "}\n");
-      }
     }
 
     /* This part below still needs cleanup */