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Diffstat (limited to 'absl/base/internal/sysinfo.h')
-rw-r--r-- | absl/base/internal/sysinfo.h | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/absl/base/internal/sysinfo.h b/absl/base/internal/sysinfo.h new file mode 100644 index 000000000000..f21de14325c7 --- /dev/null +++ b/absl/base/internal/sysinfo.h @@ -0,0 +1,64 @@ +// Copyright 2017 The Abseil Authors. +// +// 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. +// +// This file includes routines to find out characteristics +// of the machine a program is running on. It is undoubtedly +// system-dependent. + +// Functions listed here that accept a pid_t as an argument act on the +// current process if the pid_t argument is 0 +// All functions here are thread-hostile due to file caching unless +// commented otherwise. + +#ifndef ABSL_BASE_INTERNAL_SYSINFO_H_ +#define ABSL_BASE_INTERNAL_SYSINFO_H_ + +#ifndef _WIN32 +#include <sys/types.h> +#else +#include <intsafe.h> +#endif + +#include "absl/base/port.h" + +namespace absl { +namespace base_internal { + +// Nominal core processor cycles per second of each processor. This is _not_ +// necessarily the frequency of the CycleClock counter (see cycleclock.h) +// Thread-safe. +double NominalCPUFrequency(); + +// Number of logical processors (hyperthreads) in system. See +// //base/cpuid/cpuid.h for more CPU-related info. Thread-safe. +int NumCPUs(); + +// Return the thread id of the current thread, as told by the system. +// No two currently-live threads implemented by the OS shall have the same ID. +// Thread ids of exited threads may be reused. Multiple user-level threads +// may have the same thread ID if multiplexed on the same OS thread. +// +// On Linux, you may send a signal to the resulting ID with kill(). However, +// it is recommended for portability that you use pthread_kill() instead. +#ifdef _WIN32 +// On Windows, process id and thread id are of the same type according to +// the return types of GetProcessId() and GetThreadId() are both DWORD. +using pid_t = DWORD; +#endif +pid_t GetTID(); + +} // namespace base_internal +} // namespace absl + +#endif // ABSL_BASE_INTERNAL_SYSINFO_H_ |