Merge pull request #38 from ethereum/create-fn-search

"Create" function name search heuristic

Doxyfile

@@ -99,7 +99,7 @@ WARN_LOGFILE           =
 #---------------------------------------------------------------------------
 # Configuration options related to the input files
 #---------------------------------------------------------------------------
-INPUT                  = include/evmc/evmc.h
+INPUT                  = include/evmc/
 INPUT_ENCODING         = UTF-8
 FILE_PATTERNS          =
 RECURSIVE              = NO
@@ -264,7 +264,7 @@ EXPAND_ONLY_PREDEF     = NO
 SEARCH_INCLUDES        = YES
 INCLUDE_PATH           =
 INCLUDE_FILE_PATTERNS  =
-PREDEFINED             =
+PREDEFINED             = EVMC_DOCUMENTATION=1
 EXPAND_AS_DEFINED      =
 SKIP_FUNCTION_MACROS   = YES
 #---------------------------------------------------------------------------

examples/examplevm/CMakeLists.txt

@@ -1,4 +1,4 @@
-# EVMC -- Ethereum Client-VM Connector API
+# EVMC: Ethereum Client-VM Connector API
 # Copyright 2018 Pawel Bylica.
 # Licensed under the MIT License. See the LICENSE file.
 
@@ -6,9 +6,16 @@ include(GNUInstallDirs)
 
 add_library(evmc-examplevm examplevm.c)
 target_link_libraries(evmc-examplevm PRIVATE evmc)
-set_target_properties(evmc-examplevm PROPERTIES DEBUG_POSTFIX "")
+set_target_properties(
+    evmc-examplevm PROPERTIES
+    DEBUG_POSTFIX ""
+    RUNTIME_OUTPUT_DIRECTORY ..
+    LIBRARY_OUTPUT_DIRECTORY ..
+)
 
-install(TARGETS evmc-examplevm
+install(
+    TARGETS evmc-examplevm
     ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
     LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
-    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+)

examples/examplevm/examplevm.c

@@ -11,7 +11,7 @@ struct examplevm
     int verbose;
 };
 
-static void evmc_destroy(struct evmc_instance* evm)
+static void destroy(struct evmc_instance* evm)
 {
     free(evm);
 }
@@ -19,7 +19,7 @@ static void evmc_destroy(struct evmc_instance* evm)
 /// Example options.
 ///
 /// VMs are allowed to omit this function implementation.
-int evmc_set_option(struct evmc_instance* instance, char const* name, char const* value)
+static int set_option(struct evmc_instance* instance, char const* name, char const* value)
 {
     struct examplevm* vm = (struct examplevm*)instance;
     if (strcmp(name, "verbose") == 0)
@@ -34,7 +34,7 @@ int evmc_set_option(struct evmc_instance* instance, char const* name, char const
     return 0;
 }
 
-static void evmc_release_result(struct evmc_result const* result)
+static void release_result(struct evmc_result const* result)
 {
     (void)result;
 }
@@ -103,7 +103,7 @@ static struct evmc_result execute(struct evmc_instance* instance,
         return ret;
     }
 
-    ret.release = evmc_release_result;
+    ret.release = release_result;
     ret.status_code = EVMC_FAILURE;
     ret.gas_left = 0;
 
@@ -119,9 +119,9 @@ struct evmc_instance* evmc_create_examplevm()
         .abi_version = EVMC_ABI_VERSION,
         .name = "examplevm",
         .version = "0.0.0",
-        .destroy = evmc_destroy,
+        .destroy = destroy,
         .execute = execute,
-        .set_option = evmc_set_option,
+        .set_option = set_option,
     };
     struct examplevm* vm = calloc(1, sizeof(struct examplevm));
     struct evmc_instance* interface = &vm->instance;

include/evmc/evmc.h

@@ -732,16 +732,24 @@ struct evmc_instance
 
 /* END Python CFFI declarations */
 
+#if EVMC_DOCUMENTATION
 /**
  * Example of a function creating an instance of an example EVM implementation.
  *
- *  Each EVM implementation MUST provide a function returning an EVM instance.
- *  The function SHOULD be named `evmc_create_<vm-name>(void)`.
+ * Each EVM implementation MUST provide a function returning an EVM instance.
+ * The function SHOULD be named `evmc_create_<vm-name>(void)`. If the VM name contains hyphens
+ * replaces them with underscores in the function names.
  *
- *  @return  EVM instance or NULL indicating instance creation failure.
+ * @par Binaries naming convention
+ * For VMs distributed as shared libraries, the name of the library SHOULD match the VM name.
+ * The convetional library filename prefixes and extensions SHOULD be ignored by the Client.
+ * For example, the shared library with the "beta-interpreter" implementation may be named
+ * `libbeta-interpreter.so`.
  *
- *  struct evmc_instance* evmc_create_examplevm(void);
+ * @return  EVM instance or NULL indicating instance creation failure.
  */
+struct evmc_instance* evmc_create_examplevm(void);
+#endif
 
 #if __cplusplus
 }

include/evmc/utils.h

@@ -8,5 +8,5 @@
 #ifdef _MSC_VER
 #define EVMC_EXPORT __declspec(dllexport)
 #else
-#define EVMC_EXPORT __attribute__ ((visibility ("default")))
+#define EVMC_EXPORT __attribute__((visibility("default")))
 #endif

test/vmtester/CMakeLists.txt

@@ -8,6 +8,7 @@ hunter_add_package(Boost COMPONENTS program_options filesystem system)
 find_package(Boost CONFIG REQUIRED program_options filesystem system)
 
 add_executable(evmc-vmtester vmtester.hpp vmtester.cpp tests.cpp)
+set_target_properties(evmc-vmtester PROPERTIES RUNTIME_OUTPUT_DIRECTORY ..)
 
 target_link_libraries(
     evmc-vmtester

test/vmtester/vmtester.cpp

@@ -35,6 +35,38 @@ evmc_instance* get_vm_instance()
     return vm.get();
 }
 
+std::vector<std::string> get_vm_names(const fs::path path)
+{
+    std::vector<std::string> names;
+
+    // Get the filename without extension.
+    auto name = path.stem().string();
+
+    // Skip the optional library name prefix.
+    const std::string lib_name_prefix{"lib"};
+    if (name.find(lib_name_prefix) == 0)
+        name = name.substr(lib_name_prefix.size());
+
+    size_t hyphen_pos = 0;
+    const std::string hyphen{"-"};
+    if ((hyphen_pos = name.find(hyphen)) != std::string::npos)
+    {
+        // Replace the hyphen with underscore.
+        name.replace(hyphen_pos, hyphen.size(), "_");
+        names.emplace_back(name);
+
+        // Also add the  name without the hyphen-separated prefix.
+        names.emplace_back(name.substr(hyphen_pos + hyphen.size()));
+    }
+    else
+    {
+        // Add the filename as the name.
+        names.emplace_back(std::move(name));
+    }
+
+    return names;
+}
+
 int main(int argc, char* argv[])
 {
     try
@@ -65,23 +97,37 @@ int main(int argc, char* argv[])
 
         opts::notify(variables_map);
 
-        auto symbols = dll::library_info{vm_path}.symbols();
-        auto it = std::find_if(symbols.begin(), symbols.end(), [](const std::string& symbol) {
-            return symbol.find("evmc_create_") == 0;
-        });
-        if (it == symbols.end())
+        std::cout << "Testing " << vm_path.filename().string() << "\n"
+                  << "Path: " << vm_path.string() << "\n";
+
+        for (auto&& name : get_vm_names(vm_path))
+        {
+            try
+            {
+                const std::string create_fn_name = "evmc_create_" + name;
+                std::cout << "Seeking `" << create_fn_name << "`... ";
+                create_fn = dll::import<evmc_create_fn>(vm_path, create_fn_name);
+                std::cout << "found.\n";
+                break;
+            }
+            catch (boost::system::system_error& err)
+            {
+                using namespace boost::system;
+                const error_code windows_error{127, system_category()};
+                constexpr auto posix_error = errc::invalid_seek;
+                if (err.code() != posix_error && err.code() != windows_error)
+                    throw;  // Error other than "symbol not found".
+                std::cout << "not found.\n";
+            }
+        }
+
+        if (!create_fn)
         {
             std::cerr << "EVMC create function not found in " << vm_path.string() << "\n";
             return 2;
         }
-        const std::string& create_fn_name = *it;
-
-        std::cout << "Testing " << vm_path.filename().string() << "\n  "
-                  << "Path: " << vm_path.string() << "\n  "
-                  << "Create function: " << create_fn_name << "()\n\n";
-
-        create_fn = dll::import<evmc_create_fn>(vm_path, create_fn_name);
 
+        std::cout << std::endl;
         return RUN_ALL_TESTS();
     }
     catch (const std::exception& ex)