/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <gtest/gtest.h>
#include "ScopedSignalHandler.h"
#include "TemporaryFile.h"

#include <errno.h>
#include <fcntl.h>
#include <stdint.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>

TEST(unistd, sysconf_SC_MONOTONIC_CLOCK) {
  ASSERT_GT(sysconf(_SC_MONOTONIC_CLOCK), 0);
}

TEST(unistd, sbrk) {
  void* initial_break = sbrk(0);

  void* new_break = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(initial_break) + 2000);
  ASSERT_EQ(0, brk(new_break));

  void* final_break = sbrk(0);
  ASSERT_EQ(final_break, new_break);
}

TEST(unistd, truncate) {
  TemporaryFile tf;
  ASSERT_EQ(0, close(tf.fd));
  ASSERT_EQ(0, truncate(tf.filename, 123));

  struct stat sb;
  ASSERT_EQ(0, stat(tf.filename, &sb));
  ASSERT_EQ(123, sb.st_size);
}

TEST(unistd, truncate64) {
  TemporaryFile tf;
  ASSERT_EQ(0, close(tf.fd));
  ASSERT_EQ(0, truncate64(tf.filename, 123));

  struct stat sb;
  ASSERT_EQ(0, stat(tf.filename, &sb));
  ASSERT_EQ(123, sb.st_size);
}

TEST(unistd, ftruncate) {
  TemporaryFile tf;
  ASSERT_EQ(0, ftruncate(tf.fd, 123));
  ASSERT_EQ(0, close(tf.fd));

  struct stat sb;
  ASSERT_EQ(0, stat(tf.filename, &sb));
  ASSERT_EQ(123, sb.st_size);
}

TEST(unistd, ftruncate64) {
  TemporaryFile tf;
  ASSERT_EQ(0, ftruncate64(tf.fd, 123));
  ASSERT_EQ(0, close(tf.fd));

  struct stat sb;
  ASSERT_EQ(0, stat(tf.filename, &sb));
  ASSERT_EQ(123, sb.st_size);
}

static bool gPauseTestFlag = false;
static void PauseTestSignalHandler(int) {
  gPauseTestFlag = true;
}

TEST(unistd, pause) {
  ScopedSignalHandler handler(SIGALRM, PauseTestSignalHandler);

  alarm(1);
  ASSERT_FALSE(gPauseTestFlag);
  ASSERT_EQ(-1, pause());
  ASSERT_TRUE(gPauseTestFlag);
}

TEST(unistd, read) {
  int fd = open("/proc/version", O_RDONLY);
  ASSERT_TRUE(fd != -1);

  char buf[5];
  ASSERT_EQ(5, read(fd, buf, 5));
  ASSERT_EQ(buf[0], 'L');
  ASSERT_EQ(buf[1], 'i');
  ASSERT_EQ(buf[2], 'n');
  ASSERT_EQ(buf[3], 'u');
  ASSERT_EQ(buf[4], 'x');
  close(fd);
}

TEST(unistd, read_EBADF) {
  // read returns ssize_t which is 64-bits on LP64, so it's worth explicitly checking that
  // our syscall stubs correctly return a 64-bit -1.
  char buf[1];
  ASSERT_EQ(-1, read(-1, buf, sizeof(buf)));
  ASSERT_EQ(EBADF, errno);
}

TEST(unistd, alarm) {
  ASSERT_EQ(0U, alarm(0));
}

TEST(unistd, _exit) {
  int pid = fork();
  ASSERT_NE(-1, pid) << strerror(errno);

  if (pid == 0) {
    _exit(99);
  }

  int status;
  ASSERT_EQ(pid, waitpid(pid, &status, 0));
  ASSERT_TRUE(WIFEXITED(status));
  ASSERT_EQ(99, WEXITSTATUS(status));
}