Merge platform calculations into a DyninstPlatform.cmake

cmake/DyninstPlatform.cmake

@@ -1,5 +1,41 @@
-if(UNIX)
-    include(DyninstPlatformUnix)
+include_guard(GLOBAL)
+
+if(WIN32)
+  set(PLATFORM i386-unknown-nt4.0)
+  return()
+endif()
+
+set(PLATFORM $ENV{PLATFORM})
+message(STATUS "-- Input platform: ${PLATFORM}")
+set(VALID_PLATFORMS
+    amd64-unknown-freebsd7.2 i386-unknown-freebsd7.2 i386-unknown-linux2.4 ppc64_linux
+    x86_64-unknown-linux2.4 aarch64-unknown-linux)
+
+if(NOT PLATFORM)
+    set(INVALID_PLATFORM true)
 else()
-    include(DyninstPlatformWindows)
+    list(FIND VALID_PLATFORMS ${PLATFORM} PLATFORM_FOUND)
+    if(PLATFORM_FOUND EQUAL -1)
+        set(INVALID_PLATFORM true)
+    endif()
+endif()
+
+execute_process(COMMAND ${DYNINST_ROOT}/scripts/sysname OUTPUT_VARIABLE SYSNAME_OUT)
+string(REPLACE "\n" "" SYSPLATFORM ${SYSNAME_OUT})
+
+if(INVALID_PLATFORM)
+    # Try to set it automatically
+    execute_process(COMMAND ${DYNINST_ROOT}/scripts/dynsysname ${SYSNAME_OUT}
+                    OUTPUT_VARIABLE DYNSYSNAME_OUT)
+    string(REPLACE "\n" "" PLATFORM ${DYNSYSNAME_OUT})
+    message(STATUS "-- Attempting to automatically identify platform: ${PLATFORM}")
+endif()
+
+list(FIND VALID_PLATFORMS ${PLATFORM} PLATFORM_FOUND)
+
+if(PLATFORM_FOUND EQUAL -1)
+    message(
+        FATAL_ERROR
+            "Error: unknown platform ${PLATFORM}; please set the PLATFORM environment variable to one of the following options: ${VALID_PLATFORMS}"
+        )
 endif()