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 *
 * Copyright 2015-2016, Google Inc.
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 * 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.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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#include <grpc/support/port_platform.h>
#include "test/core/util/test_config.h"

#ifdef GRPC_TEST_PICK_PORT
#include "test/core/util/port_server_client.h"

#include <math.h>
#include <string.h>

#include <grpc/grpc.h>
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/string_util.h>
#include <grpc/support/sync.h>
#include <grpc/support/time.h>

#include "src/core/http/httpcli.h"

typedef struct freereq {
  gpr_mu *mu;
  grpc_pollset *pollset;
  int done;
} freereq;

static void destroy_pollset_and_shutdown(grpc_exec_ctx *exec_ctx, void *p,
                                         bool success) {
  grpc_pollset_destroy(p);
  gpr_free(p);
  grpc_shutdown();
}

static void freed_port_from_server(grpc_exec_ctx *exec_ctx, void *arg,
                                   const grpc_httpcli_response *response) {
  freereq *pr = arg;
  gpr_mu_lock(pr->mu);
  pr->done = 1;
  grpc_pollset_kick(pr->pollset, NULL);
  gpr_mu_unlock(pr->mu);
}

void grpc_free_port_using_server(char *server, int port) {
  grpc_httpcli_context context;
  grpc_httpcli_request req;
  freereq pr;
  char *path;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_closure *shutdown_closure;

  grpc_init();

  memset(&pr, 0, sizeof(pr));
  memset(&req, 0, sizeof(req));

  pr.pollset = gpr_malloc(grpc_pollset_size());
  grpc_pollset_init(pr.pollset, &pr.mu);
  shutdown_closure =
      grpc_closure_create(destroy_pollset_and_shutdown, pr.pollset);

  req.host = server;
  gpr_asprintf(&path, "/drop/%d", port);
  req.http.path = path;

  grpc_httpcli_context_init(&context);
  grpc_httpcli_get(&exec_ctx, &context, pr.pollset, &req,
                   GRPC_TIMEOUT_SECONDS_TO_DEADLINE(10), freed_port_from_server,
                   &pr);
  gpr_mu_lock(pr.mu);
  while (!pr.done) {
    grpc_pollset_worker *worker = NULL;
    grpc_pollset_work(&exec_ctx, pr.pollset, &worker,
                      gpr_now(GPR_CLOCK_MONOTONIC),
                      GRPC_TIMEOUT_SECONDS_TO_DEADLINE(1));
  }
  gpr_mu_unlock(pr.mu);

  grpc_httpcli_context_destroy(&context);
  grpc_exec_ctx_finish(&exec_ctx);
  grpc_pollset_shutdown(&exec_ctx, pr.pollset, shutdown_closure);
  grpc_exec_ctx_finish(&exec_ctx);
  gpr_free(path);
}

typedef struct portreq {
  gpr_mu *mu;
  grpc_pollset *pollset;
  int port;
  int retries;
  char *server;
  grpc_httpcli_context *ctx;
} portreq;

static void got_port_from_server(grpc_exec_ctx *exec_ctx, void *arg,
                                 const grpc_httpcli_response *response) {
  size_t i;
  int port = 0;
  portreq *pr = arg;
  int failed = 0;

  if (!response) {
    failed = 1;
    gpr_log(GPR_DEBUG,
            "failed port pick from server: retrying [response=NULL]");
  } else if (response->status != 200) {
    failed = 1;
    gpr_log(GPR_DEBUG, "failed port pick from server: status=%d",
            response->status);
  }

  if (failed) {
    grpc_httpcli_request req;
    memset(&req, 0, sizeof(req));
    GPR_ASSERT(pr->retries < 10);
    gpr_sleep_until(gpr_time_add(
        gpr_now(GPR_CLOCK_REALTIME),
        gpr_time_from_millis(
            (int64_t)(1000.0 * (1 + pow(1.3, pr->retries) * rand() / RAND_MAX)),
            GPR_TIMESPAN)));
    pr->retries++;
    req.host = pr->server;
    req.http.path = "/get";
    grpc_httpcli_get(exec_ctx, pr->ctx, pr->pollset, &req,
                     GRPC_TIMEOUT_SECONDS_TO_DEADLINE(10), got_port_from_server,
                     pr);
    return;
  }
  GPR_ASSERT(response);
  GPR_ASSERT(response->status == 200);
  for (i = 0; i < response->body_length; i++) {
    GPR_ASSERT(response->body[i] >= '0' && response->body[i] <= '9');
    port = port * 10 + response->body[i] - '0';
  }
  GPR_ASSERT(port > 1024);
  gpr_mu_lock(pr->mu);
  pr->port = port;
  grpc_pollset_kick(pr->pollset, NULL);
  gpr_mu_unlock(pr->mu);
}

int grpc_pick_port_using_server(char *server) {
  grpc_httpcli_context context;
  grpc_httpcli_request req;
  portreq pr;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_closure *shutdown_closure;

  grpc_init();

  memset(&pr, 0, sizeof(pr));
  memset(&req, 0, sizeof(req));
  pr.pollset = gpr_malloc(grpc_pollset_size());
  grpc_pollset_init(pr.pollset, &pr.mu);
  shutdown_closure =
      grpc_closure_create(destroy_pollset_and_shutdown, pr.pollset);
  pr.port = -1;
  pr.server = server;
  pr.ctx = &context;

  req.host = server;
  req.http.path = "/get";

  grpc_httpcli_context_init(&context);
  grpc_httpcli_get(&exec_ctx, &context, pr.pollset, &req,
                   GRPC_TIMEOUT_SECONDS_TO_DEADLINE(10), got_port_from_server,
                   &pr);
  grpc_exec_ctx_finish(&exec_ctx);
  gpr_mu_lock(pr.mu);
  while (pr.port == -1) {
    grpc_pollset_worker *worker = NULL;
    grpc_pollset_work(&exec_ctx, pr.pollset, &worker,
                      gpr_now(GPR_CLOCK_MONOTONIC),
                      GRPC_TIMEOUT_SECONDS_TO_DEADLINE(1));
  }
  gpr_mu_unlock(pr.mu);

  grpc_httpcli_context_destroy(&context);
  grpc_pollset_shutdown(&exec_ctx, pr.pollset, shutdown_closure);
  grpc_exec_ctx_finish(&exec_ctx);

  return pr.port;
}

#endif  // GRPC_TEST_PICK_PORT