[RAPPS] snapshot url support (#2925)

* [RAPPS] add snapshot url support
* [RAPPS] fix snapshot prev window won't update if size not changed
* [RAPPS] fix crash after cancel download
* [RAPPS] show broken-img if failed to create file / make network request
* [RAPPS] create a snapshots folder if it does not exist
* [RAPPS] add a helper function to perform callback
* [RAPPS] check bIsCancelled when handling ERROR_INVALID_HANDLE
* [RAPPS] remove W suffix for AsyncInetDownload
* [RAPPS] add assert for unknown event
* [RAPPS] Improve AsyncInetDownload error handling
* [RAPPS] move DisplayFailed to private, fix crash when cancelling
* [RAPPS] check for ERROR_INTERNET_OPERATION_CANCELLED
* [RAPPS] improve error logging
* [RAPPS] remove \r in error logging
* [RAPPS] rewrite AsyncInet

base/applications/rapps/include/asyncinet.h

@@ -0,0 +1,66 @@
+#ifndef ASYNC_INET
+#define ASYNC_INET
+
+
+enum ASYNC_EVENT
+{
+    ASYNCINET_DATA,           // wParam is the Data retrieved from the internet, lParam is the length of Data
+
+    ASYNCINET_COMPLETE,       // wParam and lParam are not used.
+                              // when receiving this, AsyncInet will be free soon and should not used anymore
+
+    ASYNCINET_CANCELLED,      // wParam and lParam are not used.
+                              // when receiving this, AsyncInet will be free soon and should not used anymore
+
+    ASYNCINET_ERROR           // wParam is not used. lParam specify the error code (if there is one). 
+                              // when receiving this, AsyncInet will be free soon and should not used anymore
+};
+
+typedef struct __AsyncInet ASYNCINET, * pASYNCINET;
+
+typedef int
+(*ASYNCINET_CALLBACK)(
+    pASYNCINET AsyncInet,
+    ASYNC_EVENT Event,
+    WPARAM wParam,
+    LPARAM lParam,
+    VOID* Extension
+    );
+
+typedef struct __AsyncInet
+{
+    HINTERNET hInternet;
+    HINTERNET hInetFile;
+
+    HANDLE hEventHandleCreated;
+
+    UINT ReferenceCnt;
+    CRITICAL_SECTION CriticalSection;
+    HANDLE hEventHandleClose;
+
+    BOOL bIsOpenUrlComplete;
+
+    BOOL bCancelled;
+
+    BYTE ReadBuffer[4096];
+    DWORD BytesRead;
+
+    ASYNCINET_CALLBACK Callback;
+    VOID* Extension;
+} ASYNCINET, * pASYNCINET;
+
+pASYNCINET AsyncInetDownload(LPCWSTR lpszAgent,
+    DWORD   dwAccessType,
+    LPCWSTR lpszProxy,
+    LPCWSTR lpszProxyBypass,
+    LPCWSTR lpszUrl,
+    BOOL bAllowCache,
+    ASYNCINET_CALLBACK Callback,
+    VOID* Extension
+    );
+
+BOOL AsyncInetCancel(pASYNCINET AsyncInet);
+
+VOID AsyncInetRelease(pASYNCINET AsyncInet);
+
+#endif