src/ruby/ext/grpc/rb_grpc.c

/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include "rb_grpc.h"

#include <math.h>
#include <ruby/ruby.h>
#include <ruby/vm.h>
#include <sys/time.h>

#include <grpc/grpc.h>
#include <grpc/support/time.h>
#include "rb_call.h"
#include "rb_channel.h"
#include "rb_channel_credentials.h"
#include "rb_completion_queue.h"
#include "rb_server.h"
#include "rb_server_credentials.h"

static VALUE grpc_rb_cTimeVal = Qnil;

static rb_data_type_t grpc_rb_timespec_data_type = {
    "gpr_timespec",
    {GRPC_RB_GC_NOT_MARKED, GRPC_RB_GC_DONT_FREE, GRPC_RB_MEMSIZE_UNAVAILABLE,
     {NULL, NULL}},
    NULL,
    NULL,
#ifdef RUBY_TYPED_FREE_IMMEDIATELY
    RUBY_TYPED_FREE_IMMEDIATELY
#endif
};

/* Alloc func that blocks allocation of a given object by raising an
 * exception. */
VALUE grpc_rb_cannot_alloc(VALUE cls) {
  rb_raise(rb_eTypeError,
           "allocation of %s only allowed from the gRPC native layer",
           rb_class2name(cls));
  return Qnil;
}

/* Init func that fails by raising an exception. */
VALUE grpc_rb_cannot_init(VALUE self) {
  rb_raise(rb_eTypeError,
           "initialization of %s only allowed from the gRPC native layer",
           rb_obj_classname(self));
  return Qnil;
}

/* Init/Clone func that fails by raising an exception. */
VALUE grpc_rb_cannot_init_copy(VALUE copy, VALUE self) {
  (void)self;
  rb_raise(rb_eTypeError,
           "initialization of %s only allowed from the gRPC native layer",
           rb_obj_classname(copy));
  return Qnil;
}

/* id_tv_{,u}sec are accessor methods on Ruby Time instances. */
static ID id_tv_sec;
static ID id_tv_nsec;

/**
 * grpc_rb_time_timeval creates a timeval from a ruby time object.
 *
 * This func is copied from ruby source, MRI/source/time.c, which is published
 * under the same license as the ruby.h, on which the entire extensions is
 * based.
 */
gpr_timespec grpc_rb_time_timeval(VALUE time, int interval) {
  gpr_timespec t;
  gpr_timespec *time_const;
  const char *tstr = interval ? "time interval" : "time";
  const char *want = " want <secs from epoch>|<Time>|<GRPC::TimeConst.*>";

  t.clock_type = GPR_CLOCK_REALTIME;
  switch (TYPE(time)) {
    case T_DATA:
      if (CLASS_OF(time) == grpc_rb_cTimeVal) {
        TypedData_Get_Struct(time, gpr_timespec, &grpc_rb_timespec_data_type,
                             time_const);
        t = *time_const;
      } else if (CLASS_OF(time) == rb_cTime) {
        t.tv_sec = NUM2INT(rb_funcall(time, id_tv_sec, 0));
        t.tv_nsec = NUM2INT(rb_funcall(time, id_tv_nsec, 0));
      } else {
        rb_raise(rb_eTypeError, "bad input: (%s)->c_timeval, got <%s>,%s", tstr,
                 rb_obj_classname(time), want);
      }
      break;

    case T_FIXNUM:
      t.tv_sec = FIX2LONG(time);
      if (interval && t.tv_sec < 0)
        rb_raise(rb_eArgError, "%s must be positive", tstr);
      t.tv_nsec = 0;
      break;

    case T_FLOAT:
      if (interval && RFLOAT_VALUE(time) < 0.0)
        rb_raise(rb_eArgError, "%s must be positive", tstr);
      else {
        double f, d;

        d = modf(RFLOAT_VALUE(time), &f);
        if (d < 0) {
          d += 1;
          f -= 1;
        }
        t.tv_sec = (gpr_int64)f;
        if (f != t.tv_sec) {
          rb_raise(rb_eRangeError, "%f out of Time range",
                   RFLOAT_VALUE(time));
        }
        t.tv_nsec = (int)(d * 1e9 + 0.5);
      }
      break;

    case T_BIGNUM:
      t.tv_sec = NUM2LONG(time);
      if (interval && t.tv_sec < 0)
        rb_raise(rb_eArgError, "%s must be positive", tstr);
      t.tv_nsec = 0;
      break;

    default:
      rb_raise(rb_eTypeError, "bad input: (%s)->c_timeval, got <%s>,%s", tstr,
               rb_obj_classname(time), want);
      break;
  }
  return t;
}

static void Init_grpc_status_codes() {
  /* Constants representing the status codes or grpc_status_code in status.h */
  VALUE grpc_rb_mStatusCodes =
      rb_define_module_under(grpc_rb_mGrpcCore, "StatusCodes");
  rb_define_const(grpc_rb_mStatusCodes, "OK", INT2NUM(GRPC_STATUS_OK));
  rb_define_const(grpc_rb_mStatusCodes, "CANCELLED",
                  INT2NUM(GRPC_STATUS_CANCELLED));
  rb_define_const(grpc_rb_mStatusCodes, "UNKNOWN",
                  INT2NUM(GRPC_STATUS_UNKNOWN));
  rb_define_const(grpc_rb_mStatusCodes, "INVALID_ARGUMENT",
                  INT2NUM(GRPC_STATUS_INVALID_ARGUMENT));
  rb_define_const(grpc_rb_mStatusCodes, "DEADLINE_EXCEEDED",
                  INT2NUM(GRPC_STATUS_DEADLINE_EXCEEDED));
  rb_define_const(grpc_rb_mStatusCodes, "NOT_FOUND",
                  INT2NUM(GRPC_STATUS_NOT_FOUND));
  rb_define_const(grpc_rb_mStatusCodes, "ALREADY_EXISTS",
                  INT2NUM(GRPC_STATUS_ALREADY_EXISTS));
  rb_define_const(grpc_rb_mStatusCodes, "PERMISSION_DENIED",
                  INT2NUM(GRPC_STATUS_PERMISSION_DENIED));
  rb_define_const(grpc_rb_mStatusCodes, "UNAUTHENTICATED",
                  INT2NUM(GRPC_STATUS_UNAUTHENTICATED));
  rb_define_const(grpc_rb_mStatusCodes, "RESOURCE_EXHAUSTED",
                  INT2NUM(GRPC_STATUS_RESOURCE_EXHAUSTED));
  rb_define_const(grpc_rb_mStatusCodes, "FAILED_PRECONDITION",
                  INT2NUM(GRPC_STATUS_FAILED_PRECONDITION));
  rb_define_const(grpc_rb_mStatusCodes, "ABORTED",
                  INT2NUM(GRPC_STATUS_ABORTED));
  rb_define_const(grpc_rb_mStatusCodes, "OUT_OF_RANGE",
                  INT2NUM(GRPC_STATUS_OUT_OF_RANGE));
  rb_define_const(grpc_rb_mStatusCodes, "UNIMPLEMENTED",
                  INT2NUM(GRPC_STATUS_UNIMPLEMENTED));
  rb_define_const(grpc_rb_mStatusCodes, "INTERNAL",
                  INT2NUM(GRPC_STATUS_INTERNAL));
  rb_define_const(grpc_rb_mStatusCodes, "UNAVAILABLE",
                  INT2NUM(GRPC_STATUS_UNAVAILABLE));
  rb_define_const(grpc_rb_mStatusCodes, "DATA_LOSS",
                  INT2NUM(GRPC_STATUS_DATA_LOSS));
}

/* id_at is the constructor method of the ruby standard Time class. */
static ID id_at;

/* id_inspect is the inspect method found on various ruby objects. */
static ID id_inspect;

/* id_to_s is the to_s method found on various ruby objects. */
static ID id_to_s;

/* Converts a wrapped time constant to a standard time. */
static VALUE grpc_rb_time_val_to_time(VALUE self) {
  gpr_timespec *time_const = NULL;
  gpr_timespec real_time;
  TypedData_Get_Struct(self, gpr_timespec, &grpc_rb_timespec_data_type,
                       time_const);
  real_time = gpr_convert_clock_type(*time_const, GPR_CLOCK_REALTIME);
  return rb_funcall(rb_cTime, id_at, 2, INT2NUM(real_time.tv_sec),
                    INT2NUM(real_time.tv_nsec));
}

/* Invokes inspect on the ctime version of the time val. */
static VALUE grpc_rb_time_val_inspect(VALUE self) {
  return rb_funcall(grpc_rb_time_val_to_time(self), id_inspect, 0);
}

/* Invokes to_s on the ctime version of the time val. */
static VALUE grpc_rb_time_val_to_s(VALUE self) {
  return rb_funcall(grpc_rb_time_val_to_time(self), id_to_s, 0);
}

static gpr_timespec zero_realtime;
static gpr_timespec inf_future_realtime;
static gpr_timespec inf_past_realtime;

/* Adds a module with constants that map to gpr's static timeval structs. */
static void Init_grpc_time_consts() {
  VALUE grpc_rb_mTimeConsts =
      rb_define_module_under(grpc_rb_mGrpcCore, "TimeConsts");
  grpc_rb_cTimeVal =
      rb_define_class_under(grpc_rb_mGrpcCore, "TimeSpec", rb_cObject);
  zero_realtime = gpr_time_0(GPR_CLOCK_REALTIME);
  inf_future_realtime = gpr_inf_future(GPR_CLOCK_REALTIME);
  inf_past_realtime = gpr_inf_past(GPR_CLOCK_REALTIME);
  rb_define_const(
      grpc_rb_mTimeConsts, "ZERO",
      TypedData_Wrap_Struct(grpc_rb_cTimeVal, &grpc_rb_timespec_data_type,
                            (void *)&zero_realtime));
  rb_define_const(
      grpc_rb_mTimeConsts, "INFINITE_FUTURE",
      TypedData_Wrap_Struct(grpc_rb_cTimeVal, &grpc_rb_timespec_data_type,
                            (void *)&inf_future_realtime));
  rb_define_const(
      grpc_rb_mTimeConsts, "INFINITE_PAST",
      TypedData_Wrap_Struct(grpc_rb_cTimeVal, &grpc_rb_timespec_data_type,
                            (void *)&inf_past_realtime));
  rb_define_method(grpc_rb_cTimeVal, "to_time", grpc_rb_time_val_to_time, 0);
  rb_define_method(grpc_rb_cTimeVal, "inspect", grpc_rb_time_val_inspect, 0);
  rb_define_method(grpc_rb_cTimeVal, "to_s", grpc_rb_time_val_to_s, 0);
  id_at = rb_intern("at");
  id_inspect = rb_intern("inspect");
  id_to_s = rb_intern("to_s");
  id_tv_sec = rb_intern("tv_sec");
  id_tv_nsec = rb_intern("tv_nsec");
}

/*
   TODO: find an alternative to ruby_vm_at_exit that is ok in Ruby 2.0 where
   RUBY_TYPED_FREE_IMMEDIATELY is not defined.

   At the moment, registering a function using ruby_vm_at_exit segfaults in Ruby
   2.0.  This is not an issue with the gRPC handler.  More likely, this was an
   in issue with 2.0 that got resolved in 2.1 and has not been backported.
*/
#ifdef RUBY_TYPED_FREE_IMMEDIATELY
static void grpc_rb_shutdown(ruby_vm_t *vm) {
  (void)vm;
  grpc_shutdown();
}
#endif

/* Initialize the GRPC module structs */

/* grpc_rb_sNewServerRpc is the struct that holds new server rpc details. */
VALUE grpc_rb_sNewServerRpc = Qnil;
/* grpc_rb_sStatus is the struct that holds status details. */
VALUE grpc_rb_sStatus = Qnil;

/* Initialize the GRPC module. */
VALUE grpc_rb_mGRPC = Qnil;
VALUE grpc_rb_mGrpcCore = Qnil;

/* cached Symbols for members in Status struct */
VALUE sym_code = Qundef;
VALUE sym_details = Qundef;
VALUE sym_metadata = Qundef;

void Init_grpc() {
  grpc_init();

/* TODO: find alternative to ruby_vm_at_exit that is ok in Ruby 2.0 */
#ifdef RUBY_TYPED_FREE_IMMEDIATELY
  ruby_vm_at_exit(grpc_rb_shutdown);
#endif

  grpc_rb_mGRPC = rb_define_module("GRPC");
  grpc_rb_mGrpcCore = rb_define_module_under(grpc_rb_mGRPC, "Core");
  grpc_rb_sNewServerRpc =
      rb_struct_define("NewServerRpc", "method", "host",
                       "deadline", "metadata", "call", NULL);
  grpc_rb_sStatus =
      rb_struct_define("Status", "code", "details", "metadata", NULL);
  sym_code = ID2SYM(rb_intern("code"));
  sym_details = ID2SYM(rb_intern("details"));
  sym_metadata = ID2SYM(rb_intern("metadata"));

  Init_grpc_channel();
  Init_grpc_completion_queue();
  Init_grpc_call();
  Init_grpc_channel_credentials();
  Init_grpc_server();
  Init_grpc_server_credentials();
  Init_grpc_status_codes();
  Init_grpc_time_consts();
}