Implement WinINet based HTTP downloads

Author: timangus

Makefile

@@ -749,7 +749,9 @@ ifdef MINGW
     FREETYPE_CFLAGS = -Ifreetype2
   endif
 
-  USE_HTTP=0
+  ifeq ($(USE_HTTP),1)
+    CLIENT_LIBS += -lwininet
+  endif
 
   ifeq ($(ARCH),x86)
     # build 32bit
@@ -1914,8 +1916,6 @@ Q3OBJ = \
   $(B)/client/qal.o \
   $(B)/client/snd_openal.o \
   \
-  $(B)/client/cl_http_curl.o \
-  \
   $(B)/client/sv_bot.o \
   $(B)/client/sv_ccmds.o \
   $(B)/client/sv_client.o \
@@ -1971,6 +1971,14 @@ Q3OBJ = \
   $(B)/client/sys_autoupdater.o \
   $(B)/client/sys_main.o
 
+ifdef MINGW
+  Q3OBJ += \
+    $(B)/client/cl_http_windows.o
+else
+  Q3OBJ += \
+    $(B)/client/cl_http_curl.o
+endif
+
 ifdef MINGW
   Q3OBJ += \
     $(B)/client/con_passive.o

code/client/cl_http_windows.c

@@ -0,0 +1,161 @@
+/*
+===========================================================================
+Copyright (C) 2025 Tim Angus (tim@ngus.net)
+
+This file is part of Quake III Arena source code.
+
+Quake III Arena source code is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of the License,
+or (at your option) any later version.
+
+Quake III Arena source code is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Quake III Arena source code; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+===========================================================================
+*/
+
+#ifdef USE_HTTP
+
+#include "client.h"
+
+#include <windows.h>
+#include <wininet.h>
+
+static HINTERNET hInternet = NULL;
+static HINTERNET hUrl = NULL;
+
+static void DropIf(qboolean condition, const char *fmt, ...)
+{
+    char buffer[1024];
+
+    if (!condition)
+        return;
+
+    va_list argptr;
+    va_start(argptr, fmt);
+    Q_vsnprintf(buffer, sizeof(buffer), fmt, argptr);
+    va_end(argptr);
+
+    Com_Error(ERR_DROP, "Download Error: %s URL: %s", buffer, clc.downloadURL);
+}
+
+/*
+=================
+CL_HTTP_Init
+=================
+*/
+qboolean CL_HTTP_Init()
+{
+    OSVERSIONINFO osvi = {sizeof(OSVERSIONINFO)};
+    const char *windowsVersion = GetVersionEx(&osvi) ? va("Windows %lu.%lu (build %lu)",
+                                                          osvi.dwMajorVersion,
+                                                          osvi.dwMinorVersion,
+                                                          osvi.dwBuildNumber)
+                                                     : "Windows";
+
+    hInternet = InternetOpenA(
+        va("%s %s", Q3_VERSION, windowsVersion),
+        INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
+
+    return hInternet != NULL;
+}
+
+/*
+=================
+CL_HTTP_Available
+=================
+*/
+qboolean CL_HTTP_Available()
+{
+    return hInternet != NULL;
+}
+
+/*
+=================
+CL_HTTP_Shutdown
+=================
+*/
+void CL_HTTP_Shutdown(void)
+{
+    if (hInternet)
+    {
+        InternetCloseHandle(hInternet);
+        hInternet = NULL;
+    }
+}
+
+/*
+=================
+CL_HTTP_BeginDownload
+=================
+*/
+void CL_HTTP_BeginDownload(const char *remoteURL)
+{
+    DWORD httpCode = 0;
+    DWORD contentLength = 0;
+    DWORD len = sizeof(httpCode);
+    DWORD zero = 0;
+    BOOL success;
+
+    hUrl = InternetOpenUrlA(hInternet, remoteURL, NULL, 0,
+                            INTERNET_FLAG_HYPERLINK |
+                                INTERNET_FLAG_NO_CACHE_WRITE |
+                                INTERNET_FLAG_NO_COOKIES |
+                                INTERNET_FLAG_NO_UI |
+                                INTERNET_FLAG_RESYNCHRONIZE |
+                                INTERNET_FLAG_RELOAD,
+                            0);
+
+    DropIf(hUrl == NULL, "InternetOpenUrlA failed %lu", GetLastError());
+
+    success = HttpQueryInfo(hUrl, HTTP_QUERY_STATUS_CODE | HTTP_QUERY_FLAG_NUMBER, &httpCode, &len, &zero);
+    DropIf(!success, "Get HTTP_QUERY_STATUS_CODE failed %lu", GetLastError());
+
+    DropIf(httpCode >= 400, "HTTP code %lu", httpCode);
+    DropIf(httpCode != 200, "Unhandled HTTP code %lu", httpCode);
+
+    success = HttpQueryInfo(hUrl, HTTP_QUERY_CONTENT_LENGTH | HTTP_QUERY_FLAG_NUMBER, &contentLength, &len, &zero);
+    DropIf(!success, "Get HTTP_QUERY_CONTENT_LENGTH failed %lu", GetLastError());
+
+    clc.downloadSize = (int)contentLength;
+    Cvar_SetValue("cl_downloadSize", clc.downloadSize);
+}
+
+/*
+=================
+CL_HTTP_PerformDownload
+=================
+*/
+qboolean CL_HTTP_PerformDownload(void)
+{
+    static BYTE readBuffer[256 * 1024];
+    DWORD bytesRead = 0;
+    BOOL success;
+
+    DropIf(hUrl == NULL, "hUrl is NULL");
+
+    success = InternetReadFile(hUrl, readBuffer, sizeof(readBuffer), &bytesRead);
+    DropIf(!success, "InternetReadFile failed %lu", GetLastError());
+
+    if (bytesRead > 0)
+    {
+        clc.downloadCount += bytesRead;
+        Cvar_SetValue("cl_downloadCount", clc.downloadCount);
+
+        int bytesWritten = FS_Write(readBuffer, bytesRead, clc.download);
+        DropIf(bytesWritten != bytesRead, "bytesWritten != bytesRead");
+
+        return qfalse;
+    }
+
+    InternetCloseHandle(hUrl);
+    return qtrue;
+}
+
+#endif /* USE_HTTP */