Open source system call tests.

PiperOrigin-RevId: 224886231
Change-Id: I0fccb4d994601739d8b16b1d4e6b31f40297fb22

1 files changed, 248 insertions, 0 deletions

diff --git a/test/util/test_util.cc b/test/util/test_util.cc
new file mode 100644
index 000000000..7b40260d1
--- /dev/null
+++ b/test/util/test_util.cc
@@ -0,0 +1,248 @@
+// Copyright 2018 Google LLC
+//
+// 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 "test/util/test_util.h"
+
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <sys/utsname.h>
+#include <unistd.h>
+
+#include <ctime>
+#include <vector>
+#include "absl/base/attributes.h"
+#include "absl/strings/numbers.h"
+#include "absl/strings/str_cat.h"
+#include "absl/strings/str_split.h"
+#include "absl/time/time.h"
+#include "test/util/fs_util.h"
+#include "test/util/posix_error.h"
+
+namespace gvisor {
+namespace testing {
+
+#define TEST_ON_GVISOR "TEST_ON_GVISOR"
+
+bool IsRunningOnGvisor() { return GvisorPlatform() != Platform::kNative; }
+
+Platform GvisorPlatform() {
+  // Set by runner.go.
+  char* env = getenv(TEST_ON_GVISOR);
+  if (!env) {
+    return Platform::kNative;
+  }
+  if (strcmp(env, "ptrace") == 0) {
+    return Platform::kPtrace;
+  }
+  if (strcmp(env, "kvm") == 0) {
+    return Platform::kKVM;
+  }
+  LOG(FATAL) << "unknown platform " << env;
+  __builtin_unreachable();
+}
+
+// Inline cpuid instruction.  Preserve %ebx/%rbx register. In PIC compilations
+// %ebx contains the address of the global offset table. %rbx is occasionally
+// used to address stack variables in presence of dynamic allocas.
+#if defined(__x86_64__)
+#define GETCPUID(a, b, c, d, a_inp, c_inp) \
+  asm("mov %%rbx, %%rdi\n"                 \
+      "cpuid\n"                            \
+      "xchg %%rdi, %%rbx\n"                \
+      : "=a"(a), "=D"(b), "=c"(c), "=d"(d) \
+      : "a"(a_inp), "2"(c_inp))
+#endif  // defined(__x86_64__)
+
+CPUVendor GetCPUVendor() {
+  uint32_t eax, ebx, ecx, edx;
+  std::string vendor_str;
+  // Get vendor std::string (issue CPUID with eax = 0)
+  GETCPUID(eax, ebx, ecx, edx, 0, 0);
+  vendor_str.append(reinterpret_cast<char*>(&ebx), 4);
+  vendor_str.append(reinterpret_cast<char*>(&edx), 4);
+  vendor_str.append(reinterpret_cast<char*>(&ecx), 4);
+  if (vendor_str == "GenuineIntel") {
+    return CPUVendor::kIntel;
+  } else if (vendor_str == "AuthenticAMD") {
+    return CPUVendor::kAMD;
+  }
+  return CPUVendor::kUnknownVendor;
+}
+
+bool operator==(const KernelVersion& first, const KernelVersion& second) {
+  return first.major == second.major && first.minor == second.minor &&
+         first.micro == second.micro;
+}
+
+PosixErrorOr<KernelVersion> ParseKernelVersion(absl::string_view vers_str) {
+  KernelVersion version = {};
+  std::vector<std::string> values = absl::StrSplit(vers_str, absl::ByAnyChar(".-"));
+  if (values.size() == 2) {
+    ASSIGN_OR_RETURN_ERRNO(version.major, Atoi<int>(values[0]));
+    ASSIGN_OR_RETURN_ERRNO(version.minor, Atoi<int>(values[1]));
+    return version;
+  } else if (values.size() >= 3) {
+    ASSIGN_OR_RETURN_ERRNO(version.major, Atoi<int>(values[0]));
+    ASSIGN_OR_RETURN_ERRNO(version.minor, Atoi<int>(values[1]));
+    ASSIGN_OR_RETURN_ERRNO(version.micro, Atoi<int>(values[2]));
+    return version;
+  }
+  return PosixError(EINVAL, absl::StrCat("Unknown kernel release: ", vers_str));
+}
+
+PosixErrorOr<KernelVersion> GetKernelVersion() {
+  utsname buf;
+  RETURN_ERROR_IF_SYSCALL_FAIL(uname(&buf));
+  return ParseKernelVersion(buf.release);
+}
+
+void SetupGvisorDeathTest() {
+}
+
+std::string CPUSetToString(const cpu_set_t& set, size_t cpus) {
+  std::string str = "cpuset[";
+  for (unsigned int n = 0; n < cpus; n++) {
+    if (CPU_ISSET(n, &set)) {
+      if (n != 0) {
+        absl::StrAppend(&str, " ");
+      }
+      absl::StrAppend(&str, n);
+    }
+  }
+  absl::StrAppend(&str, "]");
+  return str;
+}
+
+// An overloaded operator<< makes it easy to dump the value of an OpenFd.
+std::ostream& operator<<(std::ostream& out, OpenFd const& ofd) {
+  out << ofd.fd << " -> " << ofd.link;
+  return out;
+}
+
+// An overloaded operator<< makes it easy to dump a vector of OpenFDs.
+std::ostream& operator<<(std::ostream& out, std::vector<OpenFd> const& v) {
+  for (const auto& ofd : v) {
+    out << ofd << std::endl;
+  }
+  return out;
+}
+
+PosixErrorOr<std::vector<OpenFd>> GetOpenFDs() {
+  // Get the results from /proc/self/fd.
+  ASSIGN_OR_RETURN_ERRNO(auto dir_list,
+                         ListDir("/proc/self/fd", /*skipdots=*/true));
+
+  std::vector<OpenFd> ret_fds;
+  for (const auto& str_fd : dir_list) {
+    OpenFd open_fd = {};
+    ASSIGN_OR_RETURN_ERRNO(open_fd.fd, Atoi<int>(str_fd));
+    std::string path = absl::StrCat("/proc/self/fd/", open_fd.fd);
+
+    // Resolve the link.
+    char buf[PATH_MAX] = {};
+    int ret = readlink(path.c_str(), buf, sizeof(buf));
+    if (ret < 0) {
+      if (errno == ENOENT) {
+        // The FD may have been closed, let's be resilient.
+        continue;
+      }
+
+      return PosixError(
+          errno, absl::StrCat("readlink of ", path, " returned errno ", errno));
+    }
+    open_fd.link = std::string(buf, ret);
+    ret_fds.emplace_back(std::move(open_fd));
+  }
+  return ret_fds;
+}
+
+PosixErrorOr<uint64_t> Links(const std::string& path) {
+  struct stat st;
+  if (stat(path.c_str(), &st)) {
+    return PosixError(errno, absl::StrCat("Failed to stat ", path));
+  }
+  return static_cast<uint64_t>(st.st_nlink);
+}
+
+void RandomizeBuffer(void* buffer, size_t len) {
+  struct timespec ts = {};
+  clock_gettime(CLOCK_MONOTONIC, &ts);
+  uint32_t seed = static_cast<uint32_t>(ts.tv_nsec);
+  char* const buf = static_cast<char*>(buffer);
+  for (size_t i = 0; i < len; i++) {
+    buf[i] = rand_r(&seed) % 255;
+  }
+}
+
+std::vector<std::vector<struct iovec>> GenerateIovecs(uint64_t total_size,
+                                                      void* buf,
+                                                      size_t buflen) {
+  std::vector<std::vector<struct iovec>> result;
+  for (uint64_t offset = 0; offset < total_size;) {
+    auto& iovec_array = *result.emplace(result.end());
+
+    for (; offset < total_size && iovec_array.size() < IOV_MAX;
+         offset += buflen) {
+      struct iovec iov = {};
+      iov.iov_base = buf;
+      iov.iov_len = std::min<uint64_t>(total_size - offset, buflen);
+      iovec_array.push_back(iov);
+    }
+  }
+
+  return result;
+}
+
+void SleepSafe(absl::Duration duration) {
+  if (duration == absl::ZeroDuration()) {
+    return;
+  }
+
+  struct timespec ts = absl::ToTimespec(duration);
+  int ret;
+  while (1) {
+    ret = syscall(__NR_nanosleep, &ts, &ts);
+    if (ret == 0 || (ret <= 0 && errno != EINTR)) {
+      break;
+    }
+  }
+}
+
+uint64_t Megabytes(uint64_t n) {
+  // Overflow check, upper 20 bits in n shouldn't be set.
+  CHECK(!(0xfffff00000000000 & n));
+  return n << 20;
+}
+
+bool Equivalent(uint64_t current, uint64_t target, double tolerance) {
+  auto abs_diff = target > current ? target - current : current - target;
+  return abs_diff <= static_cast<uint64_t>(tolerance * target);
+}
+void TestInit(int* argc, char*** argv) {
+  ::testing::InitGoogleTest(argc, *argv);
+  ::gflags::ParseCommandLineFlags(argc, argv, true);
+
+  // Always mask SIGPIPE as it's common and tests aren't expected to handle it.
+  struct sigaction sa = {};
+  sa.sa_handler = SIG_IGN;
+  TEST_CHECK(sigaction(SIGPIPE, &sa, nullptr) == 0);
+}
+
+}  // namespace testing
+}  // namespace gvisor