Port the HTTP / CURL download stuff from q2dos.

This is a very first cut:
* It compiles
* It doesn't crash

What's missing:
* cmake integration
* CURL should be loaded dynamically
* Integration between download code and filesystem
* Likely UTF-8 stuff
* cl_http.c needs cleanup
* Windows support

Makefile

@@ -25,6 +25,10 @@
 # User configurable options
 # -------------------------
 
+# Enables HTTP support through cURL. Used for
+# HTTP download.
+WITH_CURL:=yes
+
 # Enables the optional OpenAL sound system.
 # To use it your system needs libopenal.so.1
 # or openal32.dll (we recommend openal-soft)
@@ -373,6 +377,11 @@ endif
 
 release/quake2 : CFLAGS += -Wno-unused-result
 
+ifeq ($(WITH_CURL),yes)
+release/quake2 : CFLAGS += -DUSE_CURL
+release/quake2 : LDFLAGS += -lcurl
+endif
+
 ifeq ($(WITH_OPENAL),yes)
 ifeq ($(YQ2_OSTYPE), OpenBSD)
 release/quake2 : CFLAGS += -DUSE_OPENAL -DDEFAULT_OPENAL_DRIVER='"libopenal.so"'
@@ -668,6 +677,7 @@ CLIENT_OBJS_ := \
 	src/client/cl_download.o \
 	src/client/cl_effects.o \
 	src/client/cl_entities.o \
+	src/client/cl_http.o \
 	src/client/cl_input.o \
 	src/client/cl_inventory.o \
 	src/client/cl_keyboard.o \

src/client/cl_console.c

@@ -678,7 +678,11 @@ Con_DrawConsole(float frac)
 	}
 
 	/* draw the download bar, figure out width */
+#ifdef USE_CURL
+	if (cls.downloadname[0] && (cls.download || cls.downloadposition))
+#else
 	if (cls.download)
+#endif
 	{
 		if ((text = strrchr(cls.downloadname, '/')) != NULL)
 		{

src/client/cl_download.c

@@ -103,6 +103,14 @@ CL_RequestNextDownload(void)
 					precache_model_skin = 1;
 				}
 
+#ifdef USE_CURL
+				/* Wait for the models to download before checking * skins. */
+				if (CL_PendingHTTPDownloads())
+				{
+					return;
+				}
+#endif
+
 				/* checking for skins in the model */
 				if (!precache_model)
 				{
@@ -338,6 +346,14 @@ CL_RequestNextDownload(void)
 		precache_check = ENV_CNT;
 	}
 
+#ifdef USE_CURL
+	/* Wait for pending downloads. */
+	if (CL_PendingHTTPDownloads())
+	{
+		return;
+	}
+#endif
+
 	if (precache_check == ENV_CNT)
 	{
 		precache_check = ENV_CNT + 1;
@@ -412,8 +428,15 @@ CL_RequestNextDownload(void)
 		precache_check = TEXTURE_CNT + 999;
 	}
 
-	CL_RegisterSounds();
+#ifdef USE_CURL
+	/* Wait for pending downloads. */
+	if (CL_PendingHTTPDownloads())
+	{
+		return;
+	}
+#endif
 
+	CL_RegisterSounds();
 	CL_PrepRefresh();
 
 	MSG_WriteByte(&cls.netchan.message, clc_stringcmd);
@@ -464,6 +487,18 @@ CL_CheckOrDownloadFile(char *filename)
 		return true;
 	}
 
+#ifdef USE_CURL
+	if (CL_QueueHTTPDownload(filename))
+	{
+		/* We return true so that the precache check
+		   keeps feeding us more files. Since we have
+		   multiple HTTP connections we want to
+		   minimize latency and be constantly sending
+		   requests, not one at a time. */
+		return true;
+	}
+#endif
+
 	strcpy(cls.downloadname, filename);
 
 	/* download to a temp name, and only rename

src/client/cl_main.c

@@ -461,6 +461,10 @@ CL_Precache_f(void)
 	precache_model = 0;
 	precache_model_skin = 0;
 
+#ifdef USE_CURL
+	CL_HTTP_ResetMapAbort();
+#endif
+
 	CL_RequestNextDownload();
 }
 
@@ -541,6 +545,13 @@ CL_InitLocal(void)
 
 	cl_vwep = Cvar_Get("cl_vwep", "1", CVAR_ARCHIVE);
 
+#ifdef USE_CURL
+	cl_http_proxy = Cvar_Get("cl_http_proxy", "", 0);
+	cl_http_filelists = Cvar_Get("cl_http_filelists", "1", 0);
+	cl_http_downloads = Cvar_Get("cl_http_downloads", "1", CVAR_ARCHIVE);
+	cl_http_max_connections = Cvar_Get("cl_http_max_connections", "4", 0);
+#endif
+
 	/* register our commands */
 	Cmd_AddCommand("cmd", CL_ForwardToServer_f);
 	Cmd_AddCommand("pause", CL_Pause_f);
@@ -757,7 +768,15 @@ CL_Frame(int packetdelta, int renderdelta, int timedelta, qboolean packetframe,
 		}
 	}
 
-	// Update input stuff
+	// Run HTTP downloads more often while connecting.
+#ifdef USE_CURL
+	if (cls.state == ca_connected)
+	{
+		CL_RunHTTPDownloads();
+	}
+#endif
+
+	// Update input stuff.
 	if (packetframe || renderframe)
 	{
 		CL_ReadPackets();
@@ -786,6 +805,11 @@ CL_Frame(int packetdelta, int renderdelta, int timedelta, qboolean packetframe,
 	{
 		CL_SendCmd();
 		CL_CheckForResend();
+
+		// Run HTTP downloads during game.
+#ifdef USE_CURL
+		CL_RunHTTPDownloads();
+#endif
 	}
 
 	if (renderframe)
@@ -880,6 +904,10 @@ CL_Init(void)
 
 	M_Init();
 
+#ifdef USE_CURL
+	CL_InitHTTPDownloads();
+#endif
+
 	cls.disable_screen = true; /* don't draw yet */
 
 	CL_InitLocal();
@@ -902,6 +930,10 @@ CL_Shutdown(void)
 
 	isdown = true;
 
+#ifdef USE_CURL
+	CL_HTTP_Cleanup(true);
+#endif
+
 	CL_WriteConfiguration();
 
 	Key_WriteConsoleHistory();

src/client/cl_network.c

@@ -346,6 +346,15 @@ CL_Disconnect(void)
 		cls.download = NULL;
 	}
 
+#ifdef USE_CURL
+	CL_CancelHTTPDownloads(true);
+	cls.downloadReferer[0] = 0;
+	cls.downloadname[0] = 0;
+	cls.downloadposition = 0;
+	// TODO CURL: Rausreißen?
+	// CL_Download_Reset_KBps_counter();
+#endif
+
 	cls.state = ca_disconnected;
 
 	snd_is_underwater = false;
@@ -437,10 +446,15 @@ CL_Changing_f(void)
 	}
 
 	SCR_BeginLoadingPlaque();
-
 	cls.state = ca_connected; /* not active anymore, but not disconnected */
-
 	Com_Printf("\nChanging map...\n");
+
+#ifdef USE_CURL
+	if (cls.downloadServerRetry[0] != 0)
+	{
+		CL_SetHTTPServer(cls.downloadServerRetry);
+	}
+#endif
 }
 
 /*
@@ -583,6 +597,32 @@ CL_ConnectionlessPacket(void)
 
 		Netchan_Setup(NS_CLIENT, &cls.netchan, net_from, cls.quakePort);
 
+		// TODO CURL: Das erscheint mir sinnlos kompliziert und ist für
+		// den Fall ohne CURL wahrscheinlich recht spammy.
+
+		char *buff = NET_AdrToString(cls.netchan.remote_address);
+
+		for (int i = 1; i < Cmd_Argc(); i++)
+		{
+			char *p = Cmd_Argv(i);
+
+			if (!strncmp (p, "dlserver=", 9))
+			{
+#ifdef USE_CURL
+				p += 9;
+				Com_sprintf(cls.downloadReferer, sizeof(cls.downloadReferer), "quake2://%s", buff);
+				CL_SetHTTPServer (p);
+
+				if (cls.downloadServer[0])
+				{
+					Com_Printf("HTTP downloading enabled, URL: %s\n", cls.downloadServer);
+				}
+#else
+				Com_Printf("HTTP downloading supported by server but not the client.\n");
+#endif
+			}
+		}
+
 		MSG_WriteChar(&cls.netchan.message, clc_stringcmd);
 		MSG_WriteString(&cls.netchan.message, "new");
 		cls.state = ca_connected;

src/client/header/client.h

@@ -54,6 +54,7 @@
 #include "../vid/header/ref.h"
 #include "../vid/header/vid.h"
 
+#include "http.h"
 #include "screen.h"
 #include "keyboard.h"
 #include "console.h"
@@ -240,12 +241,22 @@ typedef struct
 	char		downloadname[MAX_OSPATH];
 	int			downloadnumber;
 	dltype_t	downloadtype;
+	size_t		downloadposition;
 	int			downloadpercent;
 
 	/* demo recording info must be here, so it isn't cleared on level change */
 	qboolean	demorecording;
 	qboolean	demowaiting; /* don't record until a non-delta message is received */
 	FILE		*demofile;
+
+#ifdef USE_CURL
+	/* http downloading */
+	dlqueue_t  downloadQueue; /* queues with files to download. */
+	dlhandle_t HTTPHandles[MAX_HTTP_HANDLES]; /* download handles. */
+	char	   downloadServer[512]; /* URL prefix to dowload from .*/
+	char	   downloadServerRetry[512]; /* retry count. */
+	char	   downloadReferer[32]; /* referer string. */
+#endif
 } client_static_t;
 
 extern client_static_t	cls;

src/client/header/http.h

@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 1997-2001 Id Software, Inc.
+ *
+ * This program 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.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * USA.
+ *
+ * =======================================================================
+ *
+ * Header for the HTTP / cURL download stuff.
+ *
+ * =======================================================================
+ */
+
+#ifdef USE_CURL
+
+// Number of max. parallel downloads.
+#define MAX_HTTP_HANDLES 16
+
+#include <curl/curl.h>
+
+typedef enum
+{
+	DLQ_STATE_NOT_STARTED,
+	DLQ_STATE_RUNNING,
+	DLQ_STATE_DONE
+} dlq_state;
+
+typedef struct dlqueue_s
+{
+	struct dlqueue_s *next;
+	char quakePath[MAX_QPATH];
+	dlq_state state;
+} dlqueue_t;
+
+typedef struct dlhandle_s
+{
+	CURL *curl;
+	char filePath[MAX_OSPATH];
+	FILE *file;
+	dlqueue_t *queueEntry;
+	size_t fileSize;
+	size_t position;
+	double speed;
+	char URL[576];
+	char *tempBuffer;
+} dlhandle_t;
+
+extern cvar_t *cl_http_downloads;
+extern cvar_t *cl_http_filelists;
+extern cvar_t *cl_http_proxy;
+extern cvar_t *cl_http_max_connections;
+
+void CL_CancelHTTPDownloads(qboolean permKill);
+void CL_InitHTTPDownloads(void);
+qboolean CL_QueueHTTPDownload(const char *quakePath);
+void CL_RunHTTPDownloads(void);
+qboolean CL_PendingHTTPDownloads(void);
+void CL_SetHTTPServer(const char *URL);
+void CL_HTTP_Cleanup(qboolean fullShutdown);
+void CL_HTTP_ResetMapAbort(void);
+
+#endif

src/client/menu/menu.c

@@ -3538,6 +3538,11 @@ static menuframework_s s_downloadoptions_menu;
 
 static menuseparator_s s_download_title;
 static menulist_s s_allow_download_box;
+
+#ifdef USE_CURL
+static menulist_s s_allow_download_http_box;
+#endif
+
 static menulist_s s_allow_download_maps_box;
 static menulist_s s_allow_download_models_box;
 static menulist_s s_allow_download_players_box;
@@ -3552,6 +3557,12 @@ DownloadCallback(void *self)
     {
         Cvar_SetValue("allow_download", (float)f->curvalue);
     }
+#ifdef USE_CURL
+	else if (f == &s_allow_download_http_box)
+	{
+		Cvar_SetValue("cl_http_downloads", f->curvalue);
+	}
+#endif
     else if (f == &s_allow_download_maps_box)
     {
         Cvar_SetValue("allow_download_maps", (float)f->curvalue);
@@ -3596,9 +3607,21 @@ DownloadOptions_MenuInit(void)
     s_allow_download_box.itemnames = yes_no_names;
     s_allow_download_box.curvalue = (Cvar_VariableValue("allow_download") != 0);
 
+#ifdef USE_CURL
+	s_allow_download_http_box.generic.type = MTYPE_SPINCONTROL;
+	s_allow_download_http_box.generic.x	= 0;
+	s_allow_download_http_box.generic.y	= y += 20;
+	s_allow_download_http_box.generic.name	= "http downloading";
+	s_allow_download_http_box.generic.callback = DownloadCallback;
+	s_allow_download_http_box.itemnames = yes_no_names;
+	s_allow_download_http_box.curvalue = (Cvar_VariableValue("cl_http_downloads") != 0);
+#else
+	y += 10;
+#endif
+
     s_allow_download_maps_box.generic.type = MTYPE_SPINCONTROL;
     s_allow_download_maps_box.generic.x = 0;
-    s_allow_download_maps_box.generic.y = y += 20;
+    s_allow_download_maps_box.generic.y = y += 10;
     s_allow_download_maps_box.generic.name = "maps";
     s_allow_download_maps_box.generic.callback = DownloadCallback;
     s_allow_download_maps_box.itemnames = yes_no_names;
@@ -3634,6 +3657,11 @@ DownloadOptions_MenuInit(void)
 
     Menu_AddItem(&s_downloadoptions_menu, &s_download_title);
     Menu_AddItem(&s_downloadoptions_menu, &s_allow_download_box);
+
+#ifdef USE_CURL
+	Menu_AddItem(&s_downloadoptions_menu, &s_allow_download_http_box);
+#endif
+
     Menu_AddItem(&s_downloadoptions_menu, &s_allow_download_maps_box);
     Menu_AddItem(&s_downloadoptions_menu, &s_allow_download_players_box);
     Menu_AddItem(&s_downloadoptions_menu, &s_allow_download_models_box);