Assorted portability enhancements (#1800)

* Introduce some Platform calls for managing dynamic libraries

* Add Platform::WriteFATSectors

* Introduce some Platform calls for managing dynamic libraries

* Add Platform::WriteFATSectors

* Change includes of "../types.h" to "types.h"

- Makes it easier to directly include these headers in downstream projects

* Change an include of "../Wifi.h" to "Wifi.h"

* Allow CommonFuncs.cpp to compile on Android

* Tidy up some logging calls

- Use Platform::Log in LAN_Socket.cpp
- Soften some warnings to Debug logs (since they don't necessarily represent problems)

* Add Platform::EnterGBAMode

- Gracefully stop the emulator if trying to enter GBA mode

* Soften some logs that most players won't care about

* Soften some more logs

* Introduce Platform wrappers for file operations

* Fix pointer spacing

* Fix more style nits

* Log the errno when ftruncate fails

* Fix FileSeek offset argument

- With an s32 offset, we couldn't access files larger than 2GB

* Revise Platform::StopEmu to address feedback

- Remove Platform::EnterGBAMode in favor of adding a reason to Platform::StopEmu
- Also rename Platform::StopEmu to Platform::SignalStop
- Add an optional argument to NDS::Stop
- Use the new argument everywhere that the console stops itself

* Rename FileGetString to FileReadLine

- It conveys the meaning better

* Rename FileSeekOrigin::Set to Start

- It conveys the meaning better

* Change definition of FileGetString to FileReadLine

- Oops, almost forgot it

* Rename FlushFile to FileFlush

- To remain consistent with the other File functions

* Add a FileType usage

* Fix line break in FileSeekOrigin

* Document Platform::DeInit

* Clarify that StopReason::Unknown doesn't always mean an error

* Move and document FileType::HostFile

* Remove Platform::OpenDataFile

- Nothing currently uses it

* Refactor Platform::OpenFile and Platform::OpenLocalFile to accept a FileMode enum instead of a string

- The enum is converted to fopen flags under the hood
- The file type is used to decide whether to add the "b" flag
- Some helper functions are exposed for the benefit of consistent behavior among frontends
- Equivalent behavior is maintained

* Fix a tab that should be spaces

* Use Windows' 64-bit implementations of fseek/ftell

* Move Platform::IsBinaryFile to Platform.cpp

- It could vary by frontend

* Remove an unused FileType

* Rename an enum constant

* Document various Platform items

* Use Platform::DynamicLibrary to load libandroid

- And clean it up at the end

* Fix a typo

* Pass the correct filetype to FATStorage

- Since it can be used for DSI NAND images or for SD cards

* Remove Platform::FileType

src/ARMJIT_Memory.cpp

@@ -112,6 +112,7 @@ bool FaultHandler(FaultDescription& faultDesc);
 
 #if defined(__ANDROID__)
 #define ASHMEM_DEVICE "/dev/ashmem"
+Platform::DynamicLibrary* Libandroid = nullptr;
 #endif
 
 #if defined(__SWITCH__)
@@ -753,14 +754,13 @@ void Init()
     MemoryBase = MemoryBase + AddrSpaceSize*2;
 
 #if defined(__ANDROID__)
-    static void* libandroid = dlopen("libandroid.so", RTLD_LAZY | RTLD_LOCAL);
+    Libandroid = Platform::DynamicLibrary_Load("libandroid.so");
     using type_ASharedMemory_create = int(*)(const char* name, size_t size);
-    static void* symbol = dlsym(libandroid, "ASharedMemory_create");
-    static auto shared_memory_create = reinterpret_cast<type_ASharedMemory_create>(symbol);
+    auto ASharedMemory_create = reinterpret_cast<type_ASharedMemory_create>(Platform::DynamicLibrary_LoadFunction(Libandroid, "ASharedMemory_create"));
 
-    if (shared_memory_create)
+    if (ASharedMemory_create)
     {
-        MemoryFile = shared_memory_create("melondsfastmem", MemoryTotalSize);
+        MemoryFile = ASharedMemory_create("melondsfastmem", MemoryTotalSize);
     }
     else
     {
@@ -775,13 +775,13 @@ void Init()
     MemoryFile = shm_open(fastmemPidName, O_RDWR | O_CREAT | O_EXCL, 0600);
     if (MemoryFile == -1)
     {
-        Log(LogLevel::Error, "Failed to open memory using shm_open!");
+        Log(LogLevel::Error, "Failed to open memory using shm_open! (%s)", strerror(errno));
     }
     shm_unlink(fastmemPidName);
 #endif
     if (ftruncate(MemoryFile, MemoryTotalSize) < 0)
     {
-        Log(LogLevel::Error, "Failed to allocate memory using ftruncate!");
+        Log(LogLevel::Error, "Failed to allocate memory using ftruncate! (%s)", strerror(errno));
     }
 
     struct sigaction sa;
@@ -830,6 +830,15 @@ void DeInit()
 
     munmap(MemoryBase, MemoryTotalSize);
     close(MemoryFile);
+
+#if defined(__ANDROID__)
+    if (Libandroid)
+    {
+        Platform::DynamicLibrary_Unload(Libandroid);
+        Libandroid = nullptr;
+    }
+#endif
+
 #endif
 }