1 files changed, 190 insertions, 0 deletions

diff --git a/src/core/arm/symbols.cpp b/src/core/arm/symbols.cpp
new file mode 100644
index 000000000..26c44f0c7
--- /dev/null
+++ b/src/core/arm/symbols.cpp
@@ -0,0 +1,190 @@
+// Copyright 2022 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/bit_field.h"
+#include "common/common_funcs.h"
+#include "core/arm/symbols.h"
+#include "core/core.h"
+#include "core/memory.h"
+
+namespace Core {
+namespace {
+
+constexpr u64 ELF_DYNAMIC_TAG_NULL = 0;
+constexpr u64 ELF_DYNAMIC_TAG_STRTAB = 5;
+constexpr u64 ELF_DYNAMIC_TAG_SYMTAB = 6;
+constexpr u64 ELF_DYNAMIC_TAG_SYMENT = 11;
+
+enum class ELFSymbolType : u8 {
+    None = 0,
+    Object = 1,
+    Function = 2,
+    Section = 3,
+    File = 4,
+    Common = 5,
+    TLS = 6,
+};
+
+enum class ELFSymbolBinding : u8 {
+    Local = 0,
+    Global = 1,
+    Weak = 2,
+};
+
+enum class ELFSymbolVisibility : u8 {
+    Default = 0,
+    Internal = 1,
+    Hidden = 2,
+    Protected = 3,
+};
+
+struct ELF64Symbol {
+    u32 name_index;
+    union {
+        u8 info;
+
+        BitField<0, 4, ELFSymbolType> type;
+        BitField<4, 4, ELFSymbolBinding> binding;
+    };
+    ELFSymbolVisibility visibility;
+    u16 sh_index;
+    u64 value;
+    u64 size;
+};
+static_assert(sizeof(ELF64Symbol) == 0x18, "ELF64Symbol has incorrect size.");
+
+struct ELF32Symbol {
+    u32 name_index;
+    u32 value;
+    u32 size;
+    union {
+        u8 info;
+
+        BitField<0, 4, ELFSymbolType> type;
+        BitField<4, 4, ELFSymbolBinding> binding;
+    };
+    ELFSymbolVisibility visibility;
+    u16 sh_index;
+};
+static_assert(sizeof(ELF32Symbol) == 0x10, "ELF32Symbol has incorrect size.");
+
+} // Anonymous namespace
+
+namespace Symbols {
+
+template <typename Word, typename ELFSymbol, typename ByteReader>
+static Symbols GetSymbols(ByteReader ReadBytes) {
+    const auto Read8{[&](u64 index) {
+        u8 ret;
+        ReadBytes(&ret, index, sizeof(u8));
+        return ret;
+    }};
+
+    const auto Read32{[&](u64 index) {
+        u32 ret;
+        ReadBytes(&ret, index, sizeof(u32));
+        return ret;
+    }};
+
+    const auto ReadWord{[&](u64 index) {
+        Word ret;
+        ReadBytes(&ret, index, sizeof(Word));
+        return ret;
+    }};
+
+    const u32 mod_offset = Read32(4);
+
+    if (Read32(mod_offset) != Common::MakeMagic('M', 'O', 'D', '0')) {
+        return {};
+    }
+
+    VAddr string_table_offset{};
+    VAddr symbol_table_offset{};
+    u64 symbol_entry_size{};
+
+    const auto dynamic_offset = Read32(mod_offset + 0x4) + mod_offset;
+
+    VAddr dynamic_index = dynamic_offset;
+    while (true) {
+        const Word tag = ReadWord(dynamic_index);
+        const Word value = ReadWord(dynamic_index + sizeof(Word));
+        dynamic_index += 2 * sizeof(Word);
+
+        if (tag == ELF_DYNAMIC_TAG_NULL) {
+            break;
+        }
+
+        if (tag == ELF_DYNAMIC_TAG_STRTAB) {
+            string_table_offset = value;
+        } else if (tag == ELF_DYNAMIC_TAG_SYMTAB) {
+            symbol_table_offset = value;
+        } else if (tag == ELF_DYNAMIC_TAG_SYMENT) {
+            symbol_entry_size = value;
+        }
+    }
+
+    if (string_table_offset == 0 || symbol_table_offset == 0 || symbol_entry_size == 0) {
+        return {};
+    }
+
+    Symbols out;
+
+    VAddr symbol_index = symbol_table_offset;
+    while (symbol_index < string_table_offset) {
+        ELFSymbol symbol{};
+        ReadBytes(&symbol, symbol_index, sizeof(ELFSymbol));
+
+        VAddr string_offset = string_table_offset + symbol.name_index;
+        std::string name;
+        for (u8 c = Read8(string_offset); c != 0; c = Read8(++string_offset)) {
+            name += static_cast<char>(c);
+        }
+
+        symbol_index += symbol_entry_size;
+        out[name] = std::make_pair(symbol.value, symbol.size);
+    }
+
+    return out;
+}
+
+Symbols GetSymbols(VAddr base, Core::Memory::Memory& memory, bool is_64) {
+    const auto ReadBytes{
+        [&](void* ptr, size_t offset, size_t size) { memory.ReadBlock(base + offset, ptr, size); }};
+
+    if (is_64) {
+        return GetSymbols<u64, ELF64Symbol>(ReadBytes);
+    } else {
+        return GetSymbols<u32, ELF32Symbol>(ReadBytes);
+    }
+}
+
+Symbols GetSymbols(std::span<const u8> data, bool is_64) {
+    const auto ReadBytes{[&](void* ptr, size_t offset, size_t size) {
+        std::memcpy(ptr, data.data() + offset, size);
+    }};
+
+    if (is_64) {
+        return GetSymbols<u64, ELF64Symbol>(ReadBytes);
+    } else {
+        return GetSymbols<u32, ELF32Symbol>(ReadBytes);
+    }
+}
+
+std::optional<std::string> GetSymbolName(const Symbols& symbols, VAddr addr) {
+    const auto iter = std::find_if(symbols.cbegin(), symbols.cend(), [addr](const auto& pair) {
+        const auto& [name, sym_info] = pair;
+        const auto& [start_address, size] = sym_info;
+        const auto end_address = start_address + size;
+        return addr >= start_address && addr < end_address;
+    });
+
+    if (iter == symbols.cend()) {
+        return std::nullopt;
+    }
+
+    return iter->first;
+}
+
+} // namespace Symbols
+} // namespace Core