nghttp2/src/shrpx_mruby.cc

238 lines
6.1 KiB
C++

/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2015 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include "shrpx_mruby.h"
#include <mruby/compile.h>
#include <mruby/string.h>
#include "shrpx_downstream.h"
#include "shrpx_config.h"
#include "shrpx_mruby_module.h"
#include "shrpx_downstream_connection.h"
#include "shrpx_log.h"
namespace shrpx {
namespace mruby {
MRubyContext::MRubyContext(mrb_state *mrb, mrb_value app, mrb_value env)
: mrb_(mrb), app_(std::move(app)), env_(std::move(env)) {}
MRubyContext::~MRubyContext() {
if (mrb_) {
mrb_close(mrb_);
}
}
int MRubyContext::run_app(Downstream *downstream, int phase) {
if (!mrb_) {
return 0;
}
MRubyAssocData data{downstream, phase};
mrb_->ud = &data;
int rv = 0;
auto ai = mrb_gc_arena_save(mrb_);
auto ai_d = defer([ai, this]() { mrb_gc_arena_restore(mrb_, ai); });
const char *method;
switch (phase) {
case PHASE_REQUEST:
if (!mrb_respond_to(mrb_, app_, mrb_intern_lit(mrb_, "on_req"))) {
return 0;
}
method = "on_req";
break;
case PHASE_RESPONSE:
if (!mrb_respond_to(mrb_, app_, mrb_intern_lit(mrb_, "on_resp"))) {
return 0;
}
method = "on_resp";
break;
default:
assert(0);
}
auto res = mrb_funcall(mrb_, app_, method, 1, env_);
(void)res;
if (mrb_->exc) {
// If response has been committed, ignore error
if (downstream->get_response_state() != DownstreamState::MSG_COMPLETE) {
rv = -1;
}
auto exc = mrb_obj_value(mrb_->exc);
auto inspect = mrb_inspect(mrb_, exc);
LOG(ERROR) << "Exception caught while executing mruby code: "
<< mrb_str_to_cstr(mrb_, inspect);
}
mrb_->ud = nullptr;
return rv;
}
int MRubyContext::run_on_request_proc(Downstream *downstream) {
return run_app(downstream, PHASE_REQUEST);
}
int MRubyContext::run_on_response_proc(Downstream *downstream) {
return run_app(downstream, PHASE_RESPONSE);
}
void MRubyContext::delete_downstream(Downstream *downstream) {
if (!mrb_) {
return;
}
delete_downstream_from_module(mrb_, downstream);
}
namespace {
mrb_value instantiate_app(mrb_state *mrb, RProc *proc) {
mrb->ud = nullptr;
auto res = mrb_top_run(mrb, proc, mrb_top_self(mrb), 0);
if (mrb->exc) {
auto exc = mrb_obj_value(mrb->exc);
auto inspect = mrb_inspect(mrb, exc);
LOG(ERROR) << "Exception caught while executing mruby code: "
<< mrb_str_to_cstr(mrb, inspect);
return mrb_nil_value();
}
return res;
}
} // namespace
// Based on
// https://github.com/h2o/h2o/blob/master/lib/handler/mruby.c. It is
// very hard to write these kind of code because mruby has almost no
// documentation about compiling or generating code, at least at the
// time of this writing.
RProc *compile(mrb_state *mrb, const StringRef &filename) {
if (filename.empty()) {
return nullptr;
}
auto infile = fopen(filename.c_str(), "rb");
if (infile == nullptr) {
LOG(ERROR) << "Could not open mruby file " << filename;
return nullptr;
}
auto infile_d = defer(fclose, infile);
auto mrbc = mrbc_context_new(mrb);
if (mrbc == nullptr) {
LOG(ERROR) << "mrb_context_new failed";
return nullptr;
}
auto mrbc_d = defer(mrbc_context_free, mrb, mrbc);
auto parser = mrb_parse_file(mrb, infile, nullptr);
if (parser == nullptr) {
LOG(ERROR) << "mrb_parse_nstring failed";
return nullptr;
}
auto parser_d = defer(mrb_parser_free, parser);
if (parser->nerr != 0) {
LOG(ERROR) << "mruby parser detected parse error";
return nullptr;
}
auto proc = mrb_generate_code(mrb, parser);
if (proc == nullptr) {
LOG(ERROR) << "mrb_generate_code failed";
return nullptr;
}
return proc;
}
std::unique_ptr<MRubyContext> create_mruby_context(const StringRef &filename) {
if (filename.empty()) {
return std::make_unique<MRubyContext>(nullptr, mrb_nil_value(),
mrb_nil_value());
}
auto mrb = mrb_open();
if (mrb == nullptr) {
LOG(ERROR) << "mrb_open failed";
return nullptr;
}
auto ai = mrb_gc_arena_save(mrb);
auto req_proc = compile(mrb, filename);
if (!req_proc) {
mrb_gc_arena_restore(mrb, ai);
LOG(ERROR) << "Could not compile mruby code " << filename;
mrb_close(mrb);
return nullptr;
}
auto env = init_module(mrb);
auto app = instantiate_app(mrb, req_proc);
if (mrb_nil_p(app)) {
mrb_gc_arena_restore(mrb, ai);
LOG(ERROR) << "Could not instantiate mruby app from " << filename;
mrb_close(mrb);
return nullptr;
}
mrb_gc_arena_restore(mrb, ai);
// TODO These are not necessary, because we retain app and env?
mrb_gc_protect(mrb, env);
mrb_gc_protect(mrb, app);
return std::make_unique<MRubyContext>(mrb, std::move(app), std::move(env));
}
mrb_sym intern_ptr(mrb_state *mrb, void *ptr) {
auto p = reinterpret_cast<uintptr_t>(ptr);
return mrb_intern(mrb, reinterpret_cast<const char *>(&p), sizeof(p));
}
void check_phase(mrb_state *mrb, int phase, int phase_mask) {
if ((phase & phase_mask) == 0) {
mrb_raise(mrb, E_RUNTIME_ERROR, "operation was not allowed in this phase");
}
}
} // namespace mruby
} // namespace shrpx