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authorthegeorg <thegeorg@yandex-team.com>2022-11-07 19:34:08 +0300
committerthegeorg <thegeorg@yandex-team.com>2022-11-07 19:34:08 +0300
commit50f76e264c70a223a34b24aa59e97bff97128f4c (patch)
treee604247a10f09df6158c172577b9bfa431f1e1b5 /contrib/libs/libfuzzer/FuzzerExtraCountersWindows.cpp
parent278a58c5af63dbd7f7a6d8b8d92dc246651242da (diff)
downloadydb-50f76e264c70a223a34b24aa59e97bff97128f4c.tar.gz
Switch fuzz tests to contrib/libs/libfuzzer
Diffstat (limited to 'contrib/libs/libfuzzer/FuzzerExtraCountersWindows.cpp')
-rw-r--r--contrib/libs/libfuzzer/FuzzerExtraCountersWindows.cpp80
1 files changed, 80 insertions, 0 deletions
diff --git a/contrib/libs/libfuzzer/FuzzerExtraCountersWindows.cpp b/contrib/libs/libfuzzer/FuzzerExtraCountersWindows.cpp
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+++ b/contrib/libs/libfuzzer/FuzzerExtraCountersWindows.cpp
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+//===- FuzzerExtraCountersWindows.cpp - Extra coverage counters for Win32 -===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Extra coverage counters defined by user code for Windows.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerPlatform.h"
+#include <cstdint>
+
+#if LIBFUZZER_WINDOWS
+#include <windows.h>
+
+namespace fuzzer {
+
+//
+// The __start___libfuzzer_extra_counters variable is align 16, size 16 to
+// ensure the padding between it and the next variable in this section (either
+// __libfuzzer_extra_counters or __stop___libfuzzer_extra_counters) will be
+// located at (__start___libfuzzer_extra_counters +
+// sizeof(__start___libfuzzer_extra_counters)). Otherwise, the calculation of
+// (stop - (start + sizeof(start))) might be skewed.
+//
+// The section name, __libfuzzer_extra_countaaa ends with "aaa", so it sorts
+// before __libfuzzer_extra_counters alphabetically. We want the start symbol to
+// be placed in the section just before the user supplied counters (if present).
+//
+#pragma section(".data$__libfuzzer_extra_countaaa")
+ATTRIBUTE_ALIGNED(16)
+__declspec(allocate(".data$__libfuzzer_extra_countaaa")) uint8_t
+ __start___libfuzzer_extra_counters[16] = {0};
+
+//
+// Example of what the user-supplied counters should look like. First, the
+// pragma to create the section name. It will fall alphabetically between
+// ".data$__libfuzzer_extra_countaaa" and ".data$__libfuzzer_extra_countzzz".
+// Next, the declspec to allocate the variable inside the specified section.
+// Finally, some array, struct, whatever that is used to track the counter data.
+// The size of this variable is computed at runtime by finding the difference of
+// __stop___libfuzzer_extra_counters and __start___libfuzzer_extra_counters +
+// sizeof(__start___libfuzzer_extra_counters).
+//
+
+//
+// #pragma section(".data$__libfuzzer_extra_counters")
+// __declspec(allocate(".data$__libfuzzer_extra_counters"))
+// uint8_t any_name_variable[64 * 1024];
+//
+
+//
+// Here, the section name, __libfuzzer_extra_countzzz ends with "zzz", so it
+// sorts after __libfuzzer_extra_counters alphabetically. We want the stop
+// symbol to be placed in the section just after the user supplied counters (if
+// present). Align to 1 so there isn't any padding placed between this and the
+// previous variable.
+//
+#pragma section(".data$__libfuzzer_extra_countzzz")
+ATTRIBUTE_ALIGNED(1)
+__declspec(allocate(".data$__libfuzzer_extra_countzzz")) uint8_t
+ __stop___libfuzzer_extra_counters = 0;
+
+uint8_t *ExtraCountersBegin() {
+ return __start___libfuzzer_extra_counters +
+ sizeof(__start___libfuzzer_extra_counters);
+}
+
+uint8_t *ExtraCountersEnd() { return &__stop___libfuzzer_extra_counters; }
+
+ATTRIBUTE_NO_SANITIZE_ALL
+void ClearExtraCounters() {
+ uint8_t *Beg = ExtraCountersBegin();
+ SecureZeroMemory(Beg, ExtraCountersEnd() - Beg);
+}
+
+} // namespace fuzzer
+
+#endif