Decouple createdump from the DAC PAL

src/coreclr/debug/createdump/CMakeLists.txt

@@ -98,6 +98,7 @@ target_link_libraries(createdump_static PRIVATE minipal)
         PRIVATE
         createdump_static
         corguids
+        coreclrpal_dac
         dbgutil
         ${CMAKE_DL_LIBS}
     )

src/coreclr/debug/createdump/createdumppal.cpp

@@ -2,102 +2,21 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 #include "createdump.h"
-#include <time.h>
-#include <sys/time.h>
 
 #define INITGUID
 #include <guiddef.h>
 
+// Used by the ICLRDataTarget and ICLRDataEnumMemoryRegionsCallback implementations.
 DEFINE_GUID(IID_IUnknown, 0x00000000, 0x0000, 0x0000, 0xC0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46);
 
-#if defined(__linux__)
-#define PAL_FUNCTION_PREFIX "DAC_"
-#else
-#define PAL_FUNCTION_PREFIX
+#if defined(HOST_ARM64)
+// Used by the PAL interlocked helpers.
+bool g_arm64_atomics_present = false;
 #endif
 
-typedef int (*PFN_PAL_InitializeDLL)();
-typedef void (*PFN_PAL_TerminateEx)(int);
-
-typedef BOOL (*PFN_PAL_VirtualUnwindOutOfProc)(
-    CONTEXT *context,
-    PULONG64 functionStart,
-    SIZE_T baseAddress,
-    UnwindReadMemoryCallback readMemoryCallback,
-    bool *isSignalFrame);
-
-typedef BOOL (*PFN_PAL_GetUnwindInfoSize)(
-    SIZE_T baseAddress,
-    ULONG64 ehFrameHdrAddr,
-    UnwindReadMemoryCallback readMemoryCallback,
-    PULONG64 ehFrameStart,
-    PULONG64 ehFrameSize);
-
-bool g_initialized = false;
-PFN_PAL_InitializeDLL g_PAL_InitializeDLL = nullptr;
-PFN_PAL_TerminateEx g_PAL_TerminateEx = nullptr;
-PFN_PAL_VirtualUnwindOutOfProc g_PAL_VirtualUnwindOutOfProc = nullptr;
-PFN_PAL_GetUnwindInfoSize g_PAL_GetUnwindInfoSize = nullptr;
-
-bool
-InitializePAL()
-{
-    if (g_initialized)
-    {
-        return true;
-    }
-    g_initialized = true;
-
-    // Get createdump's path and load the DAC next to it.
-    Dl_info info;
-    if (dladdr((PVOID)&InitializePAL, &info) == 0)
-    {
-        printf_error("InitializePAL: dladdr(&InitializePAL) FAILED %s\n", dlerror());
-        return false;
-    }
-    std::string dacPath;
-    dacPath.append(info.dli_fname);
-    dacPath = GetDirectory(dacPath);
-    dacPath.append(MAKEDLLNAME_A("mscordaccore"));
-
-    // Load the DAC next to createdump
-    void* dacModule = dlopen(dacPath.c_str(), RTLD_LAZY);
-    if (dacModule == nullptr)
-    {
-        printf_error("InitializePAL: dlopen(%s) FAILED %s\n", dacPath.c_str(), dlerror());
-        return false;
-    }
-
-    // Get the PAL entry points needed by createdump
-    g_PAL_InitializeDLL = (PFN_PAL_InitializeDLL)dlsym(dacModule, PAL_FUNCTION_PREFIX "PAL_InitializeDLL");
-    if (g_PAL_InitializeDLL == nullptr)
-    {
-        printf_error("InitializePAL: dlsym(PAL_InitializeDLL) FAILED %s\n", dlerror());
-        return false;
-    }
-    if (g_PAL_InitializeDLL() != 0)
-    {
-        printf_error("InitializePAL: PAL initialization FAILED\n");
-        return false;
-    }
-    g_PAL_TerminateEx = (PFN_PAL_TerminateEx)dlsym(dacModule, PAL_FUNCTION_PREFIX "PAL_TerminateEx");
-    g_PAL_VirtualUnwindOutOfProc = (PFN_PAL_VirtualUnwindOutOfProc)dlsym(dacModule, PAL_FUNCTION_PREFIX "PAL_VirtualUnwindOutOfProc");
-    g_PAL_GetUnwindInfoSize = (PFN_PAL_GetUnwindInfoSize)dlsym(dacModule, PAL_FUNCTION_PREFIX "PAL_GetUnwindInfoSize");
-    return true;
-}
-
-void
-UninitializePAL(
-    int exitCode)
-{
-    if (g_PAL_TerminateEx != nullptr)
-    {
-        g_PAL_TerminateEx(exitCode);
-    }
-}
-
 #define TEMP_DIRECTORY_PATH "/tmp/"
 
+// Used to construct the default dump path.
 DWORD
 PALAPI
 GetTempPathA(
@@ -124,38 +43,6 @@ GetTempPathA(
     return dwPathLen;
 }
 
-BOOL
-PALAPI
-PAL_VirtualUnwindOutOfProc(
-    CONTEXT *context,
-    PULONG64 functionStart,
-    SIZE_T baseAddress,
-    UnwindReadMemoryCallback readMemoryCallback,
-    bool *isSignalFrame)
-{
-    if (!InitializePAL() || g_PAL_VirtualUnwindOutOfProc == nullptr)
-    {
-        return FALSE;
-    }
-    return g_PAL_VirtualUnwindOutOfProc(context, functionStart, baseAddress, readMemoryCallback, isSignalFrame);
-}
-
-BOOL
-PALAPI
-PAL_GetUnwindInfoSize(
-    SIZE_T baseAddress,
-    ULONG64 ehFrameHdrAddr,
-    UnwindReadMemoryCallback readMemoryCallback,
-    PULONG64 ehFrameStart,
-    PULONG64 ehFrameSize)
-{
-    if (!InitializePAL() || g_PAL_GetUnwindInfoSize == nullptr)
-    {
-        return FALSE;
-    }
-    return g_PAL_GetUnwindInfoSize(baseAddress, ehFrameHdrAddr, readMemoryCallback, ehFrameStart, ehFrameSize);
-}
-
 //
 // Used in pal\inc\rt\safecrt.h's _invalid_parameter handler
 //
@@ -192,3 +79,12 @@ DebugBreak()
 
 #endif // DEBUG
 
+// createdump_static registers this callback when embedded in a host that owns a PAL.
+// The standalone createdump executable calls createdump_main directly.
+PALIMPORT
+VOID
+PALAPI
+PAL_SetCreateDumpCallback(
+    IN PCREATEDUMP_CALLBACK callback)
+{
+}

src/coreclr/debug/createdump/main.cpp

@@ -4,34 +4,11 @@
 #include "createdump.h"
 
 extern int createdump_main(const int argc, const char* argv[]);
-extern void UninitializePAL(int exitCode);
-
-#if defined(HOST_ARM64)
-// Flag to check if atomics feature is available on
-// the machine
-bool g_arm64_atomics_present = false;
-#endif
 
 //
 // Main entry point
 //
 int __cdecl main(const int argc, const char* argv[])
 {
-    int exitCode = createdump_main(argc, argv);
-#ifdef HOST_UNIX
-    UninitializePAL(exitCode);
-#endif
-    return exitCode;
-}
-
-#ifdef HOST_UNIX
-
-PALIMPORT
-VOID
-PALAPI
-PAL_SetCreateDumpCallback(
-    IN PCREATEDUMP_CALLBACK callback) 
-{
+    return createdump_main(argc, argv);
 }
-
-#endif

src/coreclr/pal/src/CMakeLists.txt

@@ -252,7 +252,12 @@ else()
   if(NOT FEATURE_CROSSBITNESS AND NOT CLR_CMAKE_TARGET_ARCH_WASM)
     add_library(coreclrpal_dac STATIC
       exception/remote-unwind.cpp
+      ${LIBUNWIND_OBJECTS}
     )
+
+    if(CLR_CMAKE_USE_SYSTEM_LIBUNWIND)
+      target_link_libraries(coreclrpal_dac PUBLIC ${UNWIND_LIBS})
+    endif(CLR_CMAKE_USE_SYSTEM_LIBUNWIND)
   endif(NOT FEATURE_CROSSBITNESS AND NOT CLR_CMAKE_TARGET_ARCH_WASM)
 endif(CLR_CMAKE_TARGET_APPLE)