Implement pattern search without wildcards

danielkrupinski · Dec 5, 2023 · 5d37b05 · 5d37b05
1 parent 8026875
commit 5d37b05
Show file tree

Hide file tree

Showing 9 changed files with 80 additions and 48 deletions.
diff --git a/Source/Helpers/PatternNotFoundLogger.h b/Source/Helpers/PatternNotFoundLogger.h
@@ -15,16 +15,16 @@ struct PatternNotFoundLogger {
         builder.put("Failed to find pattern ");
 
         bool printedFirst = false;
-        for (const auto byte : pattern.get()) {
+        const auto wildcardChar{pattern.getWildcardChar()};
+        for (const auto byte : pattern.raw()) {
             if (printedFirst)
                 builder.put(' ');
-
-            if (byte != BytePattern::wildcardChar) {
+            if (byte != wildcardChar) {
                 if ((byte & 0xF0) == 0)
                     builder.put('0');
                 builder.putHex(static_cast<unsigned char>(byte));
             } else {
-                builder.put(BytePattern::wildcardChar);
+                builder.put(byte);
             }
 
             printedFirst = true;

diff --git a/Source/MemorySearch/BytePattern.h b/Source/MemorySearch/BytePattern.h
@@ -2,25 +2,23 @@
 
 #include <cassert>
 #include <cstddef>
+#include <optional>
 #include <span>
 #include <string_view>
 
-#include "BytePatternStorage.h"
-
 class BytePattern {
 public:
-    static constexpr auto wildcardChar = '?';
-
-    template <std::size_t StorageCapacity>
-    explicit(false) constexpr BytePattern(const BytePatternStorage<StorageCapacity>& patternStorage)
-        : pattern{ patternStorage.pattern.data(), patternStorage.size }
+    constexpr BytePattern(std::string_view pattern, std::optional<char> wildcardChar = {}) noexcept
+        : pattern{pattern}
+        , wildcardChar{wildcardChar}
     {
+        assert(!pattern.empty());
     }
 
     [[nodiscard]] BytePattern withoutFirstAndLastChar() const noexcept
     {
         if (pattern.size() > 2)
-            return BytePattern{ std::string_view{ pattern.data() + 1, pattern.size() - 2 } };
+            return BytePattern{ std::string_view{ pattern.data() + 1, pattern.size() - 2 }, wildcardChar };
         return {};
     }
 
@@ -39,7 +37,7 @@ class BytePattern {
         return pattern.back();
     }
 
-    [[nodiscard]] std::string_view get() const noexcept
+    [[nodiscard]] std::string_view raw() const noexcept
     {
         return pattern;
     }
@@ -55,13 +53,14 @@ class BytePattern {
         return true;
     }
 
-private:
-    BytePattern() = default;
-
-    explicit BytePattern(std::string_view pattern)
-        : pattern{ pattern }
+    [[nodiscard]] std::optional<char> getWildcardChar() const noexcept
     {
+        return wildcardChar;
     }
 
+private:
+    BytePattern() = default;
+
     std::string_view pattern;
+    std::optional<char> wildcardChar;
 };
diff --git a/Source/MemorySearch/BytePatternConverter.h b/Source/MemorySearch/BytePatternConverter.h
@@ -6,6 +6,7 @@
 #include <string_view>
 #include <utility>
 
+#include "PatternStringWildcard.h"
 #include <Utils/HexChars.h>
 
 enum class BytePatternConverterError {
@@ -17,14 +18,11 @@ enum class BytePatternConverterError {
 };
 
 template <std::size_t N>
+    requires (N > 0)
 struct BytePatternConverter {
-    static constexpr auto wildcardChar = '?';
-
-    static_assert(N > 0);
-
-    explicit constexpr BytePatternConverter(const char(&pattern)[N])
+    explicit constexpr BytePatternConverter(const char(&patternString)[N])
     {
-        std::ranges::copy(pattern, buffer.begin());
+        std::ranges::copy(patternString, buffer.begin());
     }
 
     using Error = BytePatternConverterError;
@@ -75,12 +73,12 @@ struct BytePatternConverter {
 
     [[nodiscard]] static constexpr bool isWildcardChar(char c) noexcept
     {
-        return c == wildcardChar;
+        return c == kPatternStringWildcard;
     }
 
     [[nodiscard]] constexpr bool isNextCharWildcard() const
     {
-        return peekNextChar() == wildcardChar;
+        return isWildcardChar(peekNextChar());
     }
 
     [[nodiscard]] constexpr bool isNextCharSpace() const
@@ -140,7 +138,7 @@ struct BytePatternConverter {
             error = Error::EndsWithWildcard;
         } else {
             advanceReadPosition();
-            putChar(wildcardChar);
+            putChar(kPatternStringWildcard);
         }
     }
 

diff --git a/Source/MemorySearch/BytePatternStorage.h b/Source/MemorySearch/BytePatternStorage.h
@@ -6,12 +6,14 @@
 #include <string_view>
 
 #include "BytePatternConverter.h"
+#include "BytePattern.h"
+#include "PatternStringWildcard.h"
 
 template <std::size_t Capacity>
 struct BytePatternStorage {
-    explicit(false) consteval BytePatternStorage(const char (&patternToConvert)[Capacity])
+    explicit(false) consteval BytePatternStorage(const char (&patternString)[Capacity])
     {
-        BytePatternConverter converter{ patternToConvert };
+        BytePatternConverter converter{patternString};
         const auto [convertedPattern, error] = converter();
         if (error == BytePatternConverterError::NoError) {
             std::ranges::copy(convertedPattern, pattern.begin());
@@ -28,8 +30,13 @@ struct BytePatternStorage {
         std::copy_n(storage.pattern.begin(), storage.size, pattern.begin());
     }
 
+    [[nodiscard]] explicit(false) operator BytePattern() const noexcept
+    {
+        return BytePattern{{pattern.data(), size}, kPatternStringWildcard};
+    }
+
     std::array<char, Capacity> pattern{};
-    std::size_t size = 0;
+    std::size_t size{0};
 
 private:
     void errorOccured();

diff --git a/Source/MemorySearch/PatternStringWildcard.h b/Source/MemorySearch/PatternStringWildcard.h
@@ -0,0 +1,3 @@
+#pragma once
+
+constexpr auto kPatternStringWildcard{'?'};
diff --git a/Source/Osiris.vcxproj b/Source/Osiris.vcxproj
@@ -172,6 +172,7 @@
     <ClInclude Include="MemorySearch\PatternFinder.h" />
     <ClInclude Include="MemorySearch\PatternFinderScalar.h" />
     <ClInclude Include="MemorySearch\PatternFinderSIMD.h" />
+    <ClInclude Include="MemorySearch\PatternStringWildcard.h" />
     <ClInclude Include="Platform\DynamicLibrary.h" />
     <ClInclude Include="Platform\Linux\LinuxDynamicLibrary.h" />
     <ClInclude Include="Platform\Linux\LinuxMessageBox.h" />

diff --git a/Source/Osiris.vcxproj.filters b/Source/Osiris.vcxproj.filters
@@ -735,6 +735,9 @@
     <ClInclude Include="CS2\Constants\AspectRatio.h">
       <Filter>CS2\Constants</Filter>
     </ClInclude>
+    <ClInclude Include="MemorySearch\PatternStringWildcard.h">
+      <Filter>MemorySearch</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="UI\Panorama\CreateGUI.js">

diff --git a/Tests/MemorySearchTests/BytePatternConverterTests.cpp b/Tests/MemorySearchTests/BytePatternConverterTests.cpp
@@ -1,6 +1,7 @@
 #include <gtest/gtest.h>
 
 #include <MemorySearch/BytePatternConverter.h>
+#include <MemorySearch/PatternStringWildcard.h>
 
 namespace
 {
@@ -41,7 +42,7 @@ TEST(BytePatternConverterTest, PatternCannotEndWithWildcard) {
 }
 
 TEST(BytePatternConverterTest, NumericValueOfWildcardCharCannotBeUsed) {
-    static_assert(BytePatternConverter<1>::wildcardChar == 0x3F);
+    static_assert(kPatternStringWildcard == 0x3F);
 
     BytePatternConverter converter{ "AA BB 3F CC" };
     const auto [converted, error] = converter();

diff --git a/Tests/MemorySearchTests/BytePatternTests.cpp b/Tests/MemorySearchTests/BytePatternTests.cpp
@@ -6,42 +6,62 @@
 #include <gtest/gtest.h>
 
 #include <MemorySearch/BytePattern.h>
-#include <MemorySearch/BytePatternLiteral.h>
+#include <MemorySearch/PatternStringWildcard.h>
 
 namespace
 {
 
+using namespace std::string_view_literals;
+
 template <std::size_t N>
 [[nodiscard]] constexpr auto createByteArray(const unsigned char(&bytes)[N])
 {
     std::array<std::byte, N> arr;
-    std::ranges::transform(bytes, arr.begin(), [](unsigned char c) { return std::byte{ c }; });
+    std::ranges::transform(bytes, arr.begin(), [](unsigned char c) { return std::byte{c}; });
     return arr;
 }
 
-TEST(BytePatternTest, PatternMatchesMemoryWhenBytesAreTheSame) {
-    constexpr auto pattern = "AB CD EF"_pat;
-    EXPECT_TRUE(BytePattern{ pattern }.matches(createByteArray({ 0xAB, 0xCD, 0xEF })));
+TEST(BytePatternWithoutWildcardTest, PatternMatchesMemoryWhenBytesAreTheSame) {
+    EXPECT_TRUE(BytePattern{"\xAB\xCD\xEF"sv}.matches(createByteArray({ 0xAB, 0xCD, 0xEF })));
 }
 
-TEST(BytePatternTest, PatternDoesNotMatchMemoryWhenBytesAreDifferent) {
-    constexpr auto pattern = "AB CD AB"_pat;
-    EXPECT_FALSE(BytePattern{ pattern }.matches(createByteArray({ 0xAB, 0xCD, 0xEF })));
+TEST(BytePatternWithoutWildcardTest, PatternDoesNotMatchMemoryWhenBytesAreDifferent) {
+    EXPECT_FALSE(BytePattern{"\xAB\xCD\xAB"sv}.matches(createByteArray({ 0xAB, 0xCD, 0xEF })));
 }
 
-TEST(BytePatternTest, NullCharsInPatternDoesNotTerminateComparison) {
-    constexpr auto pattern = "AB 00 EF 00 13"_pat;
-    EXPECT_FALSE(BytePattern{ pattern }.matches(createByteArray({ 0xAB, 0x00, 0xEF, 0x00, 0x12 })));
+TEST(BytePatternWithoutWildcardTest, NullCharsInPatternDoesNotTerminateComparison) {
+    EXPECT_FALSE(BytePattern{"\xAB\x00\xEF\x00\x13"sv}.matches(createByteArray({ 0xAB, 0x00, 0xEF, 0x00, 0x12 })));
 }
 
-TEST(BytePatternTest, BytesOnWildcardPositionsAreIgnored) {
-    constexpr auto pattern = "AB ? EF ? FF"_pat;
-    EXPECT_TRUE(BytePattern{ pattern }.matches(createByteArray({ 0xAB, 0xCC, 0xEF, 0xDD, 0xFF })));
+class BytePatternWithWildcardTest : public testing::TestWithParam<char> {
+protected:
+    [[nodiscard]] auto makePattern(std::string_view pattern) noexcept
+    {
+        return BytePattern{pattern, GetParam()};
+    }
+};
+
+TEST_P(BytePatternWithWildcardTest, PatternMatchesMemoryWhenBytesAreTheSame) {
+    EXPECT_TRUE(makePattern("\xAB\xCD\xEF"sv).matches(createByteArray({ 0xAB, 0xCD, 0xEF })));
 }
 
-TEST(BytePatternTest, WildcardCharInMemoryDoesNotMatchEveryPatternChar) {
-    constexpr auto pattern = "AB CC EF DD FF"_pat;
-    EXPECT_FALSE(BytePattern{ pattern }.matches(createByteArray({ 0xAB, BytePattern::wildcardChar, 0xEF, BytePattern::wildcardChar, 0xFF })));
+TEST_P(BytePatternWithWildcardTest, PatternDoesNotMatchMemoryWhenBytesAreDifferent) {
+    EXPECT_FALSE(makePattern("\xAB\xCD\xAB"sv).matches(createByteArray({ 0xAB, 0xCD, 0xEF })));
 }
 
+TEST_P(BytePatternWithWildcardTest, NullCharsInPatternDoesNotTerminateComparison) {
+    EXPECT_FALSE(makePattern("\xAB\x00\xEF\x00\x13"sv).matches(createByteArray({ 0xAB, 0x00, 0xEF, 0x00, 0x12 })));
+}
+
+TEST_P(BytePatternWithWildcardTest, BytesOnWildcardPositionsAreIgnored) {
+    const auto pattern = std::string{"\xAB"} + GetParam() + "\xEF" + GetParam() + "\xFF";
+    EXPECT_TRUE(makePattern(pattern).matches(createByteArray({ 0xAB, 0xCC, 0xEF, 0xDD, 0xFF })));
+}
+
+TEST_P(BytePatternWithWildcardTest, WildcardCharInMemoryDoesNotMatchEveryPatternChar) {
+    EXPECT_FALSE(makePattern("\xAB\xCC\xEF\xDD\xFF"sv).matches(createByteArray({ 0xAB, static_cast<unsigned char>(GetParam()), 0xEF, static_cast<unsigned char>(GetParam()), 0xFF })));
+}
+
+INSTANTIATE_TEST_SUITE_P(, BytePatternWithWildcardTest, testing::Values('?', '.'));
+
 }
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		#pragma once

		constexpr auto kPatternStringWildcard{'?'};