Add Try/Catch Blocks within driver

As a step towards making the driver the main function.

python/dune/perftool/cgen/__init__.py

@@ -3,6 +3,7 @@ from __future__ import absolute_import
 from cgen import *
 
 from dune.perftool.cgen.clazz import Class
+from dune.perftool.cgen.exceptions import TryCatchBlock, CatchBlock
 
 
 class Namespace(PrivateNamespace):

python/dune/perftool/cgen/exceptions.py

+""" Add Try/Catch blocks to cgen """
+
+from cgen import Block, Generable, Value
+
+
+class CatchBlock(Generable):
+    def __init__(self, exc_decl, catch_block):
+        assert isinstance(exc_decl, Value)
+        self.exc_decl = exc_decl
+        assert isinstance(catch_block, Block)
+        self.catch_block = catch_block
+
+    def generate(self):
+        yield "catch ({})\n".format("".join(self.exc_decl.generate(with_semicolon=False)))
+        for item in self.catch_block.generate():
+            yield item
+        yield "\n"
+
+class TryCatchBlock(Generable):
+    def __init__(self, try_block, catch_blocks):
+        # Store the try block
+        assert isinstance(try_block, Block)
+        self.try_block = try_block
+
+        assert all(isinstance(b, CatchBlock) for b in catch_blocks)
+        self.catch_blocks = catch_blocks
+
+    def generate(self):
+        # Yield the try block
+        yield "\n"
+        yield "try\n"
+        for item in self.try_block.generate():
+            yield item
+        yield "\n"
+
+        # and now yield all the catch blocks
+        for catch_block in self.catch_blocks:
+            for item in catch_block.generate():
+                yield item

python/dune/perftool/pdelab/driver/__init__.py

@@ -307,6 +307,21 @@ def generate_driver():
         contents.insert(len(contents) - 1, Line(text="DUMP_TIMER({}, driver, {}, true);\n".format(get_option("instrumentation_level"), timestream)))
     contents.insert(0, Line(text="\n"))
     driver_body = Block(contents)
+
+    # Wrap a try/catch block around the driver body
+    from dune.perftool.cgen import CatchBlock, TryCatchBlock, Value, Block, Line
+    catch_blocks = [CatchBlock(Value("Dune::Exception&", "e"),
+                               Block([Line("std::cerr << \"Dune reported error: \" << e << std::endl;\n"),
+                                      Line("return 1;\n"),
+                                      ])
+                               ),
+                    CatchBlock(Value("std::exception&", "e"),
+                               Block([Line("std::cerr << \"Unknown exception thrown!\" << std::endl;\n"),
+                                      Line("return 1;\n"),
+                                      ])
+                               )
+                    ]
+    driver_body = Block([TryCatchBlock(driver_body, catch_blocks)])
     driver = FunctionBody(driver_signature, driver_body)
 
     filename = get_option("driver_file")