remove unused state from CDetourDis

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 4.0)
+cmake_minimum_required(VERSION 3.29)
 project(mach_detours C CXX)
 
 set(CMAKE_C_STANDARD 23)

src/arm64/detours_arm64_disasm.cpp

@@ -36,19 +36,8 @@
 // TBZ     z0110110 bbbbbiii iiiiiiii iiittttt  & 0x7f000000 == 0x36000000  (z = size, b = bitnum, i = SignExtend(imm14:00, 64), t = Rt)
 //
 
-class CDetourDis
+namespace detour_arm64_disasm
 {
-  public:
-    explicit CDetourDis() = default;
-
-    uint8_t*   CopyInstruction(uint8_t* pDst,
-                            uint8_t* pSrc,
-                            uint8_t* *ppTarget,
-                            int32_t *plExtra);
-
-  public:
-    typedef uint8_t (CDetourDis::* COPYFUNC)(uint8_t* pbDst, uint8_t* pbSrc);
-
     union AddImm12
     {
         uint32_t Assembled;
@@ -310,37 +299,30 @@ class CDetourDis
         }
     };
 
+    static uint8_t    PureCopy32(uint8_t* pSource, uint8_t* pDest);
+    static uint8_t    EmitMovImmediate(uint32_t*& pDstInst, uint8_t rd, uint64_t immediate);
+    static uint8_t    CopyAdr(uint8_t* pSource, uint8_t* pDest, uint32_t instruction) ;
+    static uint8_t    CopyBcc(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
+    static uint8_t    CopyB(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
+    static uint8_t    CopyBl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
+    static uint8_t    CopyB_or_Bl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction, bool link);
+    static uint8_t    CopyCbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
+    static uint8_t    CopyTbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
+    static uint8_t    CopyLdrLiteral(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
 
-  protected:
+    static uint32_t GetInstruction(uint8_t* pSource)
-    uint8_t    PureCopy32(uint8_t* pSource, uint8_t* pDest);
-    uint8_t    EmitMovImmediate(uint32_t*& pDstInst, uint8_t rd, uint64_t immediate);
-    uint8_t    CopyAdr(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-    uint8_t    CopyBcc(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-    uint8_t    CopyB(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-    uint8_t    CopyBl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-    uint8_t    CopyB_or_Bl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction, bool link);
-    uint8_t    CopyCbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-    uint8_t    CopyTbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-    uint8_t    CopyLdrLiteral(uint8_t* pSource, uint8_t* pDest, uint32_t instruction);
-
-  protected:
-    uint32_t GetInstruction(uint8_t* pSource)
     {
         return ((uint32_t*)pSource)[0];
     }
 
-    uint8_t EmitInstruction(uint32_t*& pDstInst, uint32_t instruction)
+    static uint8_t EmitInstruction(uint32_t*& pDstInst, uint32_t instruction)
     {
         *pDstInst++ = instruction;
         return sizeof(uint32_t);
     }
-
-  protected:
-    uint8_t*   m_pbTarget = nullptr;
-    uint8_t    m_rbScratchDst[128] {}; // matches or exceeds rbCode
 };
 
-uint8_t CDetourDis::PureCopy32(uint8_t* pSource, uint8_t* pDest)
+uint8_t detour_arm64_disasm::PureCopy32(uint8_t* pSource, uint8_t* pDest)
 {
     *(uint32_t *)pDest = *(uint32_t*)pSource;
     return sizeof(uint32_t);
@@ -349,46 +331,7 @@ uint8_t CDetourDis::PureCopy32(uint8_t* pSource, uint8_t* pDest)
 /////////////////////////////////////////////////////////// Disassembler Code.
 //
 
-uint8_t* CDetourDis::CopyInstruction(uint8_t* pDst,
+uint8_t detour_arm64_disasm::EmitMovImmediate(uint32_t*& pDstInst, uint8_t rd, uint64_t immediate)
-                                  uint8_t* pSrc,
-                                  uint8_t* *ppTarget,
-                                  int32_t *plExtra)
-{
-    if (pDst == nullptr) {
-        pDst = m_rbScratchDst;
-    }
-
-    uint32_t Instruction = GetInstruction(pSrc);
-
-    uint32_t CopiedSize;
-    if ((Instruction & 0x1f000000) == 0x10000000) {
-        CopiedSize = CopyAdr(pSrc, pDst, Instruction);
-    } else if ((Instruction & 0xff000010) == 0x54000000) {
-        CopiedSize = CopyBcc(pSrc, pDst, Instruction);
-    } else if ((Instruction & 0x7c000000) == 0x14000000) {
-        CopiedSize = CopyB_or_Bl(pSrc, pDst, Instruction, (Instruction & 0x80000000) != 0);
-    } else if ((Instruction & 0x7e000000) == 0x34000000) {
-        CopiedSize = CopyCbz(pSrc, pDst, Instruction);
-    } else if ((Instruction & 0x7e000000) == 0x36000000) {
-        CopiedSize = CopyTbz(pSrc, pDst, Instruction);
-    } else if ((Instruction & 0x3b000000) == 0x18000000) {
-        CopiedSize = CopyLdrLiteral(pSrc, pDst, Instruction);
-    } else {
-        CopiedSize = PureCopy32(pSrc, pDst);
-    }
-
-    // If the target is needed, store our target
-    if (ppTarget) {
-        *ppTarget = m_pbTarget;
-    }
-    if (plExtra) {
-        *plExtra = CopiedSize - sizeof(uint32_t);
-    }
-
-    return pSrc + 4;
-}
-
-uint8_t CDetourDis::EmitMovImmediate(uint32_t*& pDstInst, uint8_t rd, uint64_t immediate)
 {
     uint32_t piece[4];
     piece[3] = (uint32_t)((immediate >> 48) & 0xffff);
@@ -439,7 +382,7 @@ uint8_t CDetourDis::EmitMovImmediate(uint32_t*& pDstInst, uint8_t rd, uint64_t i
     return (uint8_t)(count * sizeof(uint32_t));
 }
 
-uint8_t CDetourDis::CopyAdr(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyAdr(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     Adr19& decoded = (Adr19&)(instruction);
     uint32_t* pDstInst = (uint32_t*)(pDest);
@@ -493,13 +436,12 @@ uint8_t CDetourDis::CopyAdr(uint8_t* pSource, uint8_t* pDest, uint32_t instructi
     return (uint8_t)((uint8_t*)pDstInst - pDest);
 }
 
-uint8_t CDetourDis::CopyBcc(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyBcc(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     Bcc19& decoded = (Bcc19&)(instruction);
     uint32_t* pDstInst = (uint32_t*)(pDest);
 
     uint8_t* pTarget = pSource + decoded.Imm();
-    m_pbTarget = pTarget;
     int64_t delta = pTarget - pDest;
     int64_t delta4 = pTarget - (pDest + 4);
 
@@ -527,13 +469,12 @@ uint8_t CDetourDis::CopyBcc(uint8_t* pSource, uint8_t* pDest, uint32_t instructi
     return (uint8_t)((uint8_t*)pDstInst - pDest);
 }
 
-uint8_t CDetourDis::CopyB_or_Bl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction, bool link)
+uint8_t detour_arm64_disasm::CopyB_or_Bl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction, bool link)
 {
     Branch26& decoded = (Branch26&)(instruction);
     uint32_t* pDstInst = (uint32_t*)(pDest);
 
     uint8_t* pTarget = pSource + decoded.Imm();
-    m_pbTarget = pTarget;
     int64_t delta = pTarget - pDest;
 
     // output as B or BRL
@@ -552,23 +493,22 @@ uint8_t CDetourDis::CopyB_or_Bl(uint8_t* pSource, uint8_t* pDest, uint32_t instr
     return (uint8_t)((uint8_t*)pDstInst - pDest);
 }
 
-uint8_t CDetourDis::CopyB(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyB(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     return CopyB_or_Bl(pSource, pDest, instruction, false);
 }
 
-uint8_t CDetourDis::CopyBl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyBl(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     return CopyB_or_Bl(pSource, pDest, instruction, true);
 }
 
-uint8_t CDetourDis::CopyCbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyCbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     Cbz19& decoded = (Cbz19&)(instruction);
     uint32_t* pDstInst = (uint32_t*)(pDest);
 
     uint8_t* pTarget = pSource + decoded.Imm();
-    m_pbTarget = pTarget;
     int64_t delta = pTarget - pDest;
     int64_t delta4 = pTarget - (pDest + 4);
 
@@ -596,13 +536,12 @@ uint8_t CDetourDis::CopyCbz(uint8_t* pSource, uint8_t* pDest, uint32_t instructi
     return (uint8_t)((uint8_t*)pDstInst - pDest);
 }
 
-uint8_t CDetourDis::CopyTbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyTbz(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     Tbz14& decoded = (Tbz14&)(instruction);
     uint32_t* pDstInst = (uint32_t*)(pDest);
 
     uint8_t* pTarget = pSource + decoded.Imm();
-    m_pbTarget = pTarget;
     int64_t delta = pTarget - pDest;
     int64_t delta4 = pTarget - (pDest + 4);
 
@@ -630,7 +569,7 @@ uint8_t CDetourDis::CopyTbz(uint8_t* pSource, uint8_t* pDest, uint32_t instructi
     return (uint8_t)((uint8_t*)pDstInst - pDest);
 }
 
-uint8_t CDetourDis::CopyLdrLiteral(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
+uint8_t detour_arm64_disasm::CopyLdrLiteral(uint8_t* pSource, uint8_t* pDest, uint32_t instruction)
 {
     LdrLit19& decoded = (LdrLit19&)(instruction);
     uint32_t* pDstInst = (uint32_t*)(pDest);
@@ -667,8 +606,32 @@ uint8_t CDetourDis::CopyLdrLiteral(uint8_t* pSource, uint8_t* pDest, uint32_t in
     return (uint8_t)((uint8_t*)pDstInst - pDest);
 }
 
-void* internal_detour_copy_instruction(void* dst, void* src, void** out_target, int32_t* out_extra_len)
+uint8_t* internal_detour_copy_instruction(uint8_t* dst, uint8_t* src, uint32_t* out_extra_len)
 {
-    CDetourDis state;
+    using namespace detour_arm64_disasm;
-    return (void*)state.CopyInstruction((uint8_t*)dst, (uint8_t*)src, (uint8_t**)out_target, out_extra_len);
+
+    const uint32_t Instruction = GetInstruction(src);
+
+    uint32_t CopiedSize;
+    if ((Instruction & 0x1f000000) == 0x10000000) {
+        CopiedSize = CopyAdr(src, dst, Instruction);
+    } else if ((Instruction & 0xff000010) == 0x54000000) {
+        CopiedSize = CopyBcc(src, dst, Instruction);
+    } else if ((Instruction & 0x7c000000) == 0x14000000) {
+        CopiedSize = CopyB_or_Bl(src, dst, Instruction, (Instruction & 0x80000000) != 0);
+    } else if ((Instruction & 0x7e000000) == 0x34000000) {
+        CopiedSize = CopyCbz(src, dst, Instruction);
+    } else if ((Instruction & 0x7e000000) == 0x36000000) {
+        CopiedSize = CopyTbz(src, dst, Instruction);
+    } else if ((Instruction & 0x3b000000) == 0x18000000) {
+        CopiedSize = CopyLdrLiteral(src, dst, Instruction);
+    } else {
+        CopiedSize = PureCopy32(src, dst);
+    }
+
+    if (out_extra_len) {
+        *out_extra_len = CopiedSize - sizeof(uint32_t);
+    }
+
+    return src + 4;
 }

src/detours_disasm.h

@@ -11,7 +11,7 @@ extern "C" {
 
 #include <stdint.h>
 
-void* internal_detour_copy_instruction(void* dst, void* src, void** out_target, int32_t* out_extra_len);
+uint8_t* internal_detour_copy_instruction(uint8_t* dst, uint8_t* src, uint32_t* out_extra_len);
 
 #ifdef __cplusplus
 }

src/mach_detours.c

@@ -766,10 +766,10 @@ mach_error_t detour_attach_ex(detour_func_t* inout_pointer, detour_func_t detour
 
     while (offset_target < DETOUR_SIZE_OF_JMP) {
         const uint8_t* curr_op = src;
-        int32_t extra_len = 0;
+        uint32_t extra_len = 0;
 
         DETOUR_TRACE((" copy instruction src=%p, dest=%p\n", src, trampoline_code));
-        src = (uint8_t*)internal_detour_copy_instruction(trampoline_code, src, nullptr, &extra_len);
+        src = internal_detour_copy_instruction(trampoline_code, src, &extra_len);
         DETOUR_TRACE(("   after: src=%p (copied %d bytes)\n", src, (int)(src - curr_op)));
         trampoline_code += (src - curr_op) + extra_len;
         offset_target = (int32_t)(src - target);