Invoke capnp compile from mpgen

ryanofsky · ryanofsky · commit f89e4b32dc4e · 2033-07-09T13:34:23.000-04:00
This simplifies multiprocess build code somewhat (bitcoin/bitcoin#16367) so it only has to invoke one code generator instead of two, and is probably a little more future proof in that is should make it possible to change capnp options without any requiring changes outside libmultiprocess.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -12,7 +12,6 @@ capnp_generate_cpp(MP_PROXY_SRCS MP_PROXY_HDRS include/mp/proxy.capnp)
 
 set(MP_PUBLIC_HEADERS
   ${MP_PROXY_HDRS}
-  include/mp/proxy.h
   include/mp/proxy-io.h
   include/mp/proxy-types.h
   include/mp/proxy.capnp
@@ -38,41 +37,40 @@ set_target_properties(multiprocess PROPERTIES
 install(TARGETS multiprocess EXPORT Multiprocess ARCHIVE DESTINATION lib PUBLIC_HEADER DESTINATION include/mp)
 
 add_executable(mpgen src/mp/gen.cpp)
-target_include_directories(mpgen PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+target_include_directories(mpgen PRIVATE $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>)
 target_include_directories(mpgen PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include> $<INSTALL_INTERFACE:include>)
 target_link_libraries(mpgen PRIVATE CapnProto::capnp-rpc)
 target_link_libraries(mpgen PRIVATE -L${capnp_LIBRARY_DIRS} capnpc)
+target_link_libraries(mpgen PRIVATE multiprocess)
 set_target_properties(mpgen PROPERTIES
     INSTALL_RPATH_USE_LINK_PATH TRUE
     CXX_STANDARD 14
     CXX_STANDARD_REQUIRED YES)
 install(TARGETS mpgen EXPORT Multiprocess RUNTIME DESTINATION bin)
 
-configure_file(pkgconfig/libmultiprocess.pc.in "${CMAKE_CURRENT_BINARY_DIR}/libmultiprocess.pc" @ONLY)
-install(FILES "${CMAKE_CURRENT_BINARY_DIR}/libmultiprocess.pc" DESTINATION "lib/pkgconfig")
+configure_file(include/mp/config.h.in "${CMAKE_CURRENT_BINARY_DIR}/include/mp/config.h")
+configure_file(pkgconfig/libmultiprocess.pc.in "${CMAKE_CURRENT_BINARY_DIR}/pkgconfig/libmultiprocess.pc" @ONLY)
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/pkgconfig/libmultiprocess.pc" DESTINATION "lib/pkgconfig")
 
 install(EXPORT Multiprocess DESTINATION lib/cmake/Multiprocess)
 
-set(CAPNPC_IMPORT_DIRS "${CMAKE_CURRENT_SOURCE_DIR}/include")
-capnp_generate_cpp(FOO_PROXY_SRCS FOO_PROXY_HDRS src/mp/test/foo.capnp)
-
-
 if(BUILD_TESTING)
   add_custom_command(
     OUTPUT
+      src/mp/test/foo.capnp.h
+      src/mp/test/foo.capnp.c++
       src/mp/test/foo.capnp.proxy.h
       src/mp/test/foo.capnp.proxy-server.c++
       src/mp/test/foo.capnp.proxy-client.c++
       src/mp/test/foo.capnp.proxy-types.c++
       src/mp/test/foo.capnp.proxy-types.h
-    PRE_BUILD COMMAND ${CMAKE_COMMAND} -E make_directory src/mp/test
-    COMMAND ${CMAKE_COMMAND} -E chdir src "${CMAKE_CURRENT_BINARY_DIR}/mpgen" mp/test/foo "${CMAKE_CURRENT_SOURCE_DIR}/src/mp/test/foo.capnp" "${CMAKE_CURRENT_SOURCE_DIR}/include" "${capnp_PREFIX}/include"
+    COMMAND mpgen "${CMAKE_CURRENT_SOURCE_DIR}" "${CMAKE_CURRENT_SOURCE_DIR}/src" "${CMAKE_CURRENT_SOURCE_DIR}/src/mp/test/foo.capnp" "${CMAKE_CURRENT_SOURCE_DIR}/include" "${capnp_PREFIX}/include"
     DEPENDS src/mp/test/foo.capnp mpgen
   )
   add_executable(mptest EXCLUDE_FROM_ALL
-    ${FOO_PROXY_HDRS}
-    ${FOO_PROXY_SRCS}
     ${MP_PROXY_HDRS}
+    src/mp/test/foo.capnp.h
+    src/mp/test/foo.capnp.c++
     src/mp/test/foo.capnp.proxy.h
     src/mp/test/foo.capnp.proxy-server.c++
     src/mp/test/foo.capnp.proxy-client.c++
diff --git a/include/mp/config.h.in b/include/mp/config.h.in
@@ -0,0 +1,10 @@
+// Copyright (c) 2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef MP_CONFIG_H
+#define MP_CONFIG_H
+
+#cmakedefine capnp_PREFIX "@capnp_PREFIX@"
+
+#endif // MP_CONFIG_H
diff --git a/src/mp/gen.cpp b/src/mp/gen.cpp
@@ -2,6 +2,9 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <mp/config.h>
+#include <mp/util.h>
+
 #include <boost/optional.hpp>
 #include <capnp/schema-parser.h>
 #include <fstream>
@@ -66,49 +69,95 @@ bool BoxedType(const ::capnp::Type& type)
              type.isFloat64() || type.isEnum());
 }
 
-void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPtr<const kj::StringPtr> import_paths)
+void Generate(kj::StringPtr src_prefix,
+    kj::StringPtr include_prefix,
+    kj::StringPtr src_file,
+    kj::ArrayPtr<const kj::StringPtr> import_paths)
 {
+    std::string output_path;
+    if (src_prefix == ".") {
+        output_path = src_file;
+    } else if (!src_file.startsWith(src_prefix) || src_file.size() <= src_prefix.size() ||
+               src_file[src_prefix.size()] != '/') {
+        throw std::runtime_error("src_prefix is not src_file prefix");
+    } else {
+        output_path = src_file.slice(src_prefix.size() + 1);
+    }
+
+    std::string include_path;
+    if (include_prefix == ".") {
+        include_path = src_file;
+    } else if (!src_file.startsWith(include_prefix) || src_file.size() <= include_prefix.size() ||
+               src_file[include_prefix.size()] != '/') {
+        throw std::runtime_error("include_prefix is not src_file prefix");
+    } else {
+        include_path = src_file.slice(include_prefix.size() + 1);
+    }
+
+    std::string include_base = include_path;
+    std::string::size_type p = include_base.rfind(".");
+    if (p != std::string::npos) include_base.erase(p);
+
+    std::vector<std::string> args;
+    args.emplace_back(capnp_PREFIX "/bin/capnp");
+    args.emplace_back("compile");
+    args.emplace_back("--src-prefix=");
+    args.back().append(src_prefix.cStr(), src_prefix.size());
+    for (const auto& import_path : import_paths) {
+        args.emplace_back("--import-path=");
+        args.back().append(import_path.cStr(), import_path.size());
+    }
+    args.emplace_back("--output=" capnp_PREFIX "/bin/capnpc-c++");
+    args.emplace_back(src_file);
+    int pid = fork();
+    if (!pid) {
+        mp::ExecProcess(args);
+    }
+    int status = mp::WaitProcess(pid);
+    if (status) {
+        throw std::runtime_error("Invoking " capnp_PREFIX "/bin/capnp failed");
+    }
+
     capnp::SchemaParser parser;
-    auto file_schema = parser.parseDiskFile(input_schema, input_schema, import_paths);
+    auto file_schema = parser.parseDiskFile(src_file, src_file, import_paths);
 
-    const std::string stem = output_stem;
-    std::ofstream cpp_server(stem + ".capnp.proxy-server.c++");
-    cpp_server << "// Generated by " PROXY_BIN " from " << input_schema << "\n\n";
-    cpp_server << "#include <" << stem << ".capnp.proxy-types.h>\n";
+    std::ofstream cpp_server(output_path + ".proxy-server.c++");
+    cpp_server << "// Generated by " PROXY_BIN " from " << src_file << "\n\n";
+    cpp_server << "#include <" << include_path << ".proxy-types.h>\n";
     cpp_server << "#include <" << PROXY_TYPES << ">\n\n";
     cpp_server << "namespace mp {\n";
 
-    std::ofstream cpp_client(stem + ".capnp.proxy-client.c++");
-    cpp_client << "// Generated by " PROXY_BIN " from " << input_schema << "\n\n";
-    cpp_client << "#include <" << stem << ".capnp.proxy-types.h>\n";
+    std::ofstream cpp_client(output_path + ".proxy-client.c++");
+    cpp_client << "// Generated by " PROXY_BIN " from " << src_file << "\n\n";
+    cpp_client << "#include <" << include_path << ".proxy-types.h>\n";
     cpp_client << "#include <" << PROXY_TYPES << ">\n\n";
     cpp_client << "namespace mp {\n";
 
-    std::ofstream cpp_types(stem + ".capnp.proxy-types.c++");
-    cpp_types << "// Generated by " PROXY_BIN " from " << input_schema << "\n\n";
-    cpp_types << "#include <" << stem << ".capnp.proxy-types.h>\n";
+    std::ofstream cpp_types(output_path + ".proxy-types.c++");
+    cpp_types << "// Generated by " PROXY_BIN " from " << src_file << "\n\n";
+    cpp_types << "#include <" << include_path << ".proxy-types.h>\n";
     cpp_types << "#include <" << PROXY_TYPES << ">\n\n";
     cpp_types << "namespace mp {\n";
 
-    std::string guard = stem;
+    std::string guard = output_path;
     std::transform(guard.begin(), guard.end(), guard.begin(), [](unsigned char c) {
         return ('0' <= c && c <= '9') ? c : ('A' <= c && c <= 'Z') ? c : ('a' <= c && c <= 'z') ? c - 'a' + 'A' : '_';
     });
 
-    std::ofstream inl(stem + ".capnp.proxy-types.h");
-    inl << "// Generated by " PROXY_BIN " from " << input_schema << "\n\n";
-    inl << "#ifndef " << guard << "_CAPNP_PROXY_TYPES_H\n";
-    inl << "#define " << guard << "_CAPNP_PROXY_TYPES_H\n\n";
-    inl << "#include <" << stem << ".capnp.proxy.h>\n";
-    inl << "#include <" << stem << "-types.h>\n\n";
+    std::ofstream inl(output_path + ".proxy-types.h");
+    inl << "// Generated by " PROXY_BIN " from " << src_file << "\n\n";
+    inl << "#ifndef " << guard << "_PROXY_TYPES_H\n";
+    inl << "#define " << guard << "_PROXY_TYPES_H\n\n";
+    inl << "#include <" << include_path << ".proxy.h>\n";
+    inl << "#include <" << include_base << "-types.h>\n\n";
     inl << "namespace mp {\n";
 
-    std::ofstream h(stem + ".capnp.proxy.h");
-    h << "// Generated by " PROXY_BIN " from " << input_schema << "\n\n";
-    h << "#ifndef " << guard << "_CAPNP_PROXY_H\n";
-    h << "#define " << guard << "_CAPNP_PROXY_H\n\n";
-    h << "#include <" << stem << ".h>\n";
-    h << "#include <" << stem << ".capnp.h>\n";
+    std::ofstream h(output_path + ".proxy.h");
+    h << "// Generated by " PROXY_BIN " from " << src_file << "\n\n";
+    h << "#ifndef " << guard << "_PROXY_H\n";
+    h << "#define " << guard << "_PROXY_H\n\n";
+    h << "#include <" << include_path << ".h>\n";
+    h << "#include <" << include_base << ".h>\n";
     h << "#include <" << PROXY_DECL << ">\n\n";
     h << "namespace mp {\n";
 
@@ -117,10 +166,10 @@ void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPt
         message_namespace = value->getText();
     }
 
-    std::string output_name = output_stem;
-    size_t output_slash = output_name.rfind("/");
+    std::string base_name = include_base;
+    size_t output_slash = base_name.rfind("/");
     if (output_slash != std::string::npos) {
-        output_name.erase(0, output_slash + 1);
+        base_name.erase(0, output_slash + 1);
     }
 
     std::ostringstream methods;
@@ -182,7 +231,7 @@ void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPt
             for (const auto field : struc.getFields()) {
                 auto field_name = field.getProto().getName();
                 add_accessor(field_name);
-                dec << "    using " << Cap(field_name) << "Accessor = Accessor<" << output_name
+                dec << "    using " << Cap(field_name) << "Accessor = Accessor<" << base_name
                     << "_fields::" << Cap(field_name) << ", FIELD_IN | FIELD_OUT";
                 if (BoxedType(field.getType())) dec << " | FIELD_BOXED";
                 dec << ">;\n";
@@ -385,7 +434,7 @@ void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPt
                         client_invoke << "MakeClientParam<";
                     }
 
-                    client_invoke << "Accessor<" << output_name << "_fields::" << Cap(field_name) << ", "
+                    client_invoke << "Accessor<" << base_name << "_fields::" << Cap(field_name) << ", "
                                   << field_flags.str() << ">>(";
 
                     if (field.retval || field.args == 1) {
@@ -405,7 +454,7 @@ void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPt
                     } else {
                         server_invoke_start << "MakeServerField<" << field.args;
                     }
-                    server_invoke_start << ", Accessor<" << output_name << "_fields::" << Cap(field_name) << ", "
+                    server_invoke_start << ", Accessor<" << base_name << "_fields::" << Cap(field_name) << ", "
                                         << field_flags.str() << ">>(";
                     server_invoke_end << ")";
                 }
@@ -452,8 +501,8 @@ void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPt
         }
     }
 
-    h << methods.str() << "namespace " << output_name << "_fields {\n"
-      << accessors.str() << "} // namespace " << output_name << "_fields\n"
+    h << methods.str() << "namespace " << base_name << "_fields {\n"
+      << accessors.str() << "} // namespace " << base_name << "_fields\n"
       << dec.str();
 
     cpp_server << def_server.str();
@@ -475,13 +524,13 @@ void Generate(kj::StringPtr output_stem, kj::StringPtr input_schema, kj::ArrayPt
 int main(int argc, char** argv)
 {
     if (argc < 3) {
-        fprintf(stderr, "Usage: " PROXY_BIN " OUTPUT_STEM INPUT_SCHEMA [IMPORT_PATH...]\n");
+        fprintf(stderr, "Usage: " PROXY_BIN " SRC_PREFIX SRC_FILE [IMPORT_PATH...]\n");
         exit(1);
     }
     std::vector<kj::StringPtr> import_paths;
-    for (size_t i = 3; i < argc; ++i) {
+    for (size_t i = 4; i < argc; ++i) {
         import_paths.push_back(argv[i]);
     }
-    Generate(argv[1], argv[2], {import_paths.data(), import_paths.size()});
+    Generate(argv[1], argv[2], argv[3], {import_paths.data(), import_paths.size()});
     return 0;
 }
