frontlib refactoring
socket.h now completely wraps all the lowlevel neworking, so it would be easy
to switch away from SDL_net if needed. Also reduced global state by making an
IPC connection an object-like thing.
--- a/project_files/frontlib/events.c Sat Jun 02 22:54:09 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,2 +0,0 @@
-#include "events.h"
-
--- a/project_files/frontlib/events.h Sat Jun 02 22:54:09 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,14 +0,0 @@
-/*
- * events.h
- *
- * Created on: 01.06.2012
- * Author: simmax
- */
-
-#ifndef EVENTS_H_
-#define EVENTS_H_
-
-
-
-
-#endif /* EVENTS_H_ */
--- a/project_files/frontlib/frontlib.c Sat Jun 02 22:54:09 2012 +0200
+++ b/project_files/frontlib/frontlib.c Sun Jun 03 01:24:18 2012 +0200
@@ -1,6 +1,6 @@
#include "frontlib.h"
#include "logging.h"
-#include "nonblocksockets.h"
+#include "socket.h"
#include "ipcconn.h"
#include <SDL.h>
@@ -29,13 +29,10 @@
return -1;
}
- flib_ipcconn_init();
return 0;
}
void flib_quit() {
- flib_ipcconn_quit();
-
SDLNet_Quit();
if(!(flib_initflags | FRONTLIB_SDL_ALREADY_INITIALIZED)) {
SDL_Quit();
@@ -43,34 +40,34 @@
}
int main(int argc, char *argv[]) {
- flib_init(FRONTLIB_SDL_ALREADY_INITIALIZED);
- flib_ipcconn_start(true);
+ flib_init(0);
+
+ flib_ipcconn ipc = flib_ipcconn_create(true, "Medo42");
char data[256];
- while(flib_ipcconn_state() != IPC_NOT_CONNECTED) {
- flib_ipcconn_tick();
- int size = flib_ipcconn_recv_message(data);
+ while(flib_ipcconn_state(ipc) != IPC_NOT_CONNECTED) {
+ flib_ipcconn_tick(ipc);
+ int size = flib_ipcconn_recv_message(ipc, data);
if(size>0) {
data[size]=0;
- flib_log_i("IPC IN: %s", data);
switch(data[0]) {
case 'C':
flib_log_i("Sending config...");
- flib_ipcconn_send_messagestr("TL");
- flib_ipcconn_send_messagestr("eseed loremipsum");
- flib_ipcconn_send_messagestr("escript Missions/Training/Basic_Training_-_Bazooka.lua");
+ flib_ipcconn_send_messagestr(ipc, "TL");
+ flib_ipcconn_send_messagestr(ipc, "eseed loremipsum");
+ flib_ipcconn_send_messagestr(ipc, "escript Missions/Training/Basic_Training_-_Bazooka.lua");
break;
case '?':
flib_log_i("Sending pong...");
- flib_ipcconn_send_messagestr("!");
+ flib_ipcconn_send_messagestr(ipc, "!");
break;
case 'Q':
flib_log_i("Game interrupted.");
break;
case 'q':
flib_log_i("Game finished.");
- flib_constbuffer demobuf = flib_ipcconn_getdemo();
+ flib_constbuffer demobuf = flib_ipcconn_getdemo(ipc);
flib_log_i("Writing demo (%u bytes)...", demobuf.size);
- FILE *file = fopen("testdemo.dem", "w");
+ FILE *file = fopen("testdemo.dem", "wb");
fwrite(demobuf.data, 1, demobuf.size, file);
fclose(file);
file = NULL;
@@ -82,6 +79,7 @@
}
}
flib_log_i("IPC connection lost.");
+ flib_ipcconn_destroy(&ipc);
flib_quit();
return 0;
}
--- a/project_files/frontlib/ipcconn.c Sat Jun 02 22:54:09 2012 +0200
+++ b/project_files/frontlib/ipcconn.c Sun Jun 03 01:24:18 2012 +0200
@@ -1,97 +1,91 @@
#include "ipcconn.h"
#include "logging.h"
-#include "nonblocksockets.h"
+#include "socket.h"
-#include <SDL_net.h>
-#include <time.h>
#include <string.h>
#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
-static TCPsocket ipcListenSocket;
-static NonBlockSocket ipcConnSocket;
+typedef struct _flib_ipcconn {
+ char playerName[256];
+
+ uint8_t readBuffer[256];
+ int readBufferSize;
-static uint8_t ipcReadBuffer[256];
-static int ipcReadBufferSize;
+ flib_acceptor acceptor;
+ uint16_t port;
-static flib_vector demoBuffer;
-static char localPlayerName[255];
+ flib_tcpsocket sock;
+ flib_vector demoBuffer;
+} _flib_ipcconn;
+
+flib_ipcconn flib_ipcconn_create(bool recordDemo, const char *localPlayerName) {
+ flib_ipcconn result = malloc(sizeof(_flib_ipcconn));
+ flib_acceptor acceptor = flib_acceptor_create(0);
-void flib_ipcconn_init() {
- ipcListenSocket = NULL;
- ipcConnSocket = NULL;
- ipcReadBufferSize = 0;
- demoBuffer=NULL;
- strncpy(localPlayerName, "Local Player", 255);
-}
+ if(!result || !acceptor) {
+ free(result);
+ flib_acceptor_close(&acceptor);
+ return NULL;
+ }
+
+ result->acceptor = acceptor;
+ result->sock = NULL;
+ result->readBufferSize = 0;
+ result->port = flib_acceptor_listenport(acceptor);
-void flib_ipcconn_quit() {
- flib_vector_destroy(&demoBuffer);
- flib_ipcconn_close();
+ if(localPlayerName) {
+ strncpy(result->playerName, localPlayerName, 255);
+ } else {
+ strncpy(result->playerName, "Player", 255);
+ }
+
+ if(recordDemo) {
+ result->demoBuffer = flib_vector_create();
+ }
+
+ flib_log_i("Started listening for IPC connections on port %u", result->port);
+ return result;
}
-int flib_ipcconn_start(bool recordDemo) {
- if(ipcListenSocket || ipcConnSocket) {
- flib_log_e("flib_ipcconn_listen: Already listening or connected.");
- return -1;
- }
- IPaddress addr;
- addr.host = INADDR_ANY;
-
- /* SDL_net does not seem to have a way to listen on a random unused port
- and find out which port that is, so let's try to find one ourselves. */
- // TODO: Is socket binding fail-fast on all platforms?
- srand(time(NULL));
- rand();
- for(int i=0; i<1000; i++) {
- // IANA suggests using ports in the range 49152-65535 for things like this
- int ipcPort = 49152+(rand()%(65535-49152));
- SDLNet_Write16(ipcPort, &addr.port);
- ipcListenSocket = SDLNet_TCP_Open(&addr);
- if(!ipcListenSocket) {
- flib_log_w("Failed to start an IPC listening socket on port %i: %s", ipcPort, SDLNet_GetError());
- } else {
- flib_log_i("Listening for IPC connections on port %i.", ipcPort);
- if(recordDemo) {
- flib_vector_destroy(&demoBuffer);
- demoBuffer = flib_vector_create();
- }
- return ipcPort;
- }
- }
- flib_log_e("Unable to find a free port for IPC.");
- return -1;
+uint16_t flib_ipcconn_port(flib_ipcconn ipc) {
+ return ipc->port;
}
-void flib_ipcconn_close() {
- if(ipcListenSocket) {
- SDLNet_TCP_Close(ipcListenSocket);
- ipcListenSocket = NULL;
+void flib_ipcconn_destroy(flib_ipcconn *ipcptr) {
+ if(!ipcptr || !*ipcptr) {
+ return;
}
- flib_nbsocket_close(&ipcConnSocket);
- ipcReadBufferSize = 0;
+ flib_ipcconn ipc = *ipcptr;
+ flib_acceptor_close(&ipc->acceptor);
+ flib_socket_close(&ipc->sock);
+ flib_vector_destroy(&ipc->demoBuffer);
+ free(ipc);
+ *ipcptr = NULL;
}
-IpcConnState flib_ipcconn_state() {
- if(ipcConnSocket) {
+IpcConnState flib_ipcconn_state(flib_ipcconn ipc) {
+ if(ipc && ipc->sock) {
return IPC_CONNECTED;
- } else if(ipcListenSocket) {
+ } else if(ipc && ipc->acceptor) {
return IPC_LISTENING;
} else {
return IPC_NOT_CONNECTED;
}
}
-static void demo_record(const void *data, size_t len) {
- if(demoBuffer) {
- if(flib_vector_append(demoBuffer, data, len) < len) {
+static void demo_record(flib_ipcconn ipc, const void *data, size_t len) {
+ if(ipc->demoBuffer) {
+ if(flib_vector_append(ipc->demoBuffer, data, len) < len) {
// Out of memory, fail demo recording
- flib_vector_destroy(&demoBuffer);
+ flib_vector_destroy(&ipc->demoBuffer);
}
}
}
-static void demo_record_from_engine(const uint8_t *message) {
- if(!demoBuffer || message[0]==0) {
+static void demo_record_from_engine(flib_ipcconn ipc, const uint8_t *message) {
+ if(!ipc->demoBuffer || message[0]==0) {
return;
}
if(strchr("?CEiQqHb", message[1])) {
@@ -110,12 +104,12 @@
char converted[257];
bool memessage = message[0] >= 7 && !memcmp(message+2, "/me ", 4);
const char *template = memessage ? "s\x02* %s %s " : "s\x01%s: %s ";
- int size = snprintf(converted+1, 256, template, localPlayerName, chatMsg);
+ int size = snprintf(converted+1, 256, template, ipc->playerName, chatMsg);
converted[0] = size>255 ? 255 : size;
- demo_record(converted, converted[0]+1);
+ demo_record(ipc, converted, converted[0]+1);
}
} else {
- demo_record(message, message[0]+1);
+ demo_record(ipc, message, message[0]+1);
}
}
@@ -123,41 +117,53 @@
* Receive a single message and copy it into the data buffer.
* Returns the length of the received message, -1 when nothing is received.
*/
-int flib_ipcconn_recv_message(void *data) {
- flib_ipcconn_tick();
+int flib_ipcconn_recv_message(flib_ipcconn ipc, void *data) {
+ flib_ipcconn_tick(ipc);
- if(ipcConnSocket) {
- int size = flib_nbsocket_recv(ipcConnSocket, ipcReadBuffer+ipcReadBufferSize, sizeof(ipcReadBuffer)-ipcReadBufferSize);
+ if(ipc->sock) {
+ int size = flib_socket_nbrecv(ipc->sock, ipc->readBuffer+ipc->readBufferSize, sizeof(ipc->readBuffer)-ipc->readBufferSize);
if(size>=0) {
- ipcReadBufferSize += size;
+ ipc->readBufferSize += size;
} else {
- flib_nbsocket_close(&ipcConnSocket);
+ flib_socket_close(&ipc->sock);
}
}
- int msgsize = ipcReadBuffer[0];
- if(ipcReadBufferSize > msgsize) {
- demo_record_from_engine(ipcReadBuffer);
- memcpy(data, ipcReadBuffer+1, msgsize);
- memmove(ipcReadBuffer, ipcReadBuffer+msgsize+1, ipcReadBufferSize-(msgsize+1));
- ipcReadBufferSize -= (msgsize+1);
+ int msgsize = ipc->readBuffer[0];
+ if(ipc->readBufferSize > msgsize) {
+ demo_record_from_engine(ipc, ipc->readBuffer);
+ memcpy(data, ipc->readBuffer+1, msgsize);
+ memmove(ipc->readBuffer, ipc->readBuffer+msgsize+1, ipc->readBufferSize-(msgsize+1));
+ ipc->readBufferSize -= (msgsize+1);
return msgsize;
- } else if(!ipcConnSocket && ipcReadBufferSize>0) {
- flib_log_w("Last message from engine data stream is incomplete (received %u of %u bytes)", ipcReadBufferSize-1, msgsize);
- ipcReadBufferSize = 0;
+ } else if(!ipc->sock && ipc->readBufferSize>0) {
+ flib_log_w("Last message from engine data stream is incomplete (received %u of %u bytes)", ipc->readBufferSize-1, msgsize);
+ ipc->readBufferSize = 0;
return -1;
} else {
return -1;
}
}
-int flib_ipcconn_send_message(void *data, size_t len) {
- flib_ipcconn_tick();
+int flib_ipcconn_send_raw(flib_ipcconn ipc, void *data, size_t len) {
+ flib_ipcconn_tick(ipc);
- if(!ipcConnSocket) {
+ if(!ipc->sock) {
flib_log_w("flib_ipcconn_send_message: Not connected.");
return -1;
}
+
+ if(flib_socket_send(ipc->sock, data, len) == len) {
+ demo_record(ipc, data, len);
+ return 0;
+ } else {
+ flib_log_w("Failed or incomplete ICP write: engine connection lost.");
+ flib_socket_close(&ipc->sock);
+ return -1;
+ }
+}
+
+int flib_ipcconn_send_message(flib_ipcconn ipc, void *data, size_t len) {
if(len>255) {
flib_log_e("Attempt to send too much data to the engine in a single message.");
return -1;
@@ -166,26 +172,19 @@
uint8_t sendbuf[256];
sendbuf[0] = len;
memcpy(sendbuf+1, data, len);
- if(flib_nbsocket_blocksend(ipcConnSocket, sendbuf, len+1) == len+1) {
- demo_record(sendbuf, len+1);
- return 0;
- } else {
- flib_log_w("Failed or incomplete ICP write: engine connection lost.");
- flib_nbsocket_close(&ipcConnSocket);
- return -1;
- }
+
+ return flib_ipcconn_send_raw(ipc, sendbuf, len+1);
}
-int flib_ipcconn_send_messagestr(char *data) {
- return flib_ipcconn_send_message(data, strlen(data));
+int flib_ipcconn_send_messagestr(flib_ipcconn ipc, char *data) {
+ return flib_ipcconn_send_message(ipc, data, strlen(data));
}
-void flib_ipcconn_tick() {
- if(!ipcConnSocket && ipcListenSocket) {
- ipcConnSocket = flib_nbsocket_accept(ipcListenSocket, true);
- if(ipcConnSocket) {
- SDLNet_TCP_Close(ipcListenSocket);
- ipcListenSocket = NULL;
+void flib_ipcconn_tick(flib_ipcconn ipc) {
+ if(!ipc->sock && ipc->acceptor) {
+ ipc->sock = flib_socket_accept(ipc->acceptor, true);
+ if(ipc->sock) {
+ flib_acceptor_close(&ipc->acceptor);
}
}
}
@@ -201,20 +200,20 @@
}
}
-flib_constbuffer flib_ipcconn_getdemo() {
- if(!demoBuffer) {
+flib_constbuffer flib_ipcconn_getdemo(flib_ipcconn ipc) {
+ if(!ipc->demoBuffer) {
flib_constbuffer result = {NULL, 0};
return result;
}
- replace_gamemode(flib_vector_as_buffer(demoBuffer), 'D');
- return flib_vector_as_constbuffer(demoBuffer);
+ replace_gamemode(flib_vector_as_buffer(ipc->demoBuffer), 'D');
+ return flib_vector_as_constbuffer(ipc->demoBuffer);
}
-flib_constbuffer flib_ipcconn_getsave() {
- if(!demoBuffer) {
+flib_constbuffer flib_ipcconn_getsave(flib_ipcconn ipc) {
+ if(!ipc->demoBuffer) {
flib_constbuffer result = {NULL, 0};
return result;
}
- replace_gamemode(flib_vector_as_buffer(demoBuffer), 'S');
- return flib_vector_as_constbuffer(demoBuffer);
+ replace_gamemode(flib_vector_as_buffer(ipc->demoBuffer), 'S');
+ return flib_vector_as_constbuffer(ipc->demoBuffer);
}
--- a/project_files/frontlib/ipcconn.h Sat Jun 02 22:54:09 2012 +0200
+++ b/project_files/frontlib/ipcconn.h Sun Jun 03 01:24:18 2012 +0200
@@ -12,42 +12,35 @@
typedef enum {IPC_NOT_CONNECTED, IPC_LISTENING, IPC_CONNECTED} IpcConnState;
-/**
- * Called by flib_init(). Initialize everything related to ipc.
- */
-void flib_ipcconn_init();
+struct _flib_ipcconn;
+typedef struct _flib_ipcconn *flib_ipcconn;
/**
- * Called by flib_quit(). Free resources and shut down.
- */
-void flib_ipcconn_quit();
-
-/**
- * Start listening for a connection from the engine. The system has to be in state
- * IPC_NOT_CONNECTED when calling this function, and will be in state IPC_LISTENING
- * if the function returns successfully.
+ * Start an engine connection by listening on a random port. The selected port can
+ * be queried with flib_ipcconn_port and has to be passed to the engine.
*
* The parameter "recordDemo" can be used to control whether demo recording should
- * be enabled for this connection.
+ * be enabled for this connection. The localPlayerName is needed for demo
+ * recording purposes.
*
- * Returns the port we started listening on, or a negative value if there is an error.
+ * Returns NULL on error. Destroy the created object with flib_ipcconn_destroy.
*
- * We stop listening once a connection has been established, so if you want to start
- * the engine again and talk to it you need to call this function again after the old
- * connection is closed.
+ * We stop accepting new connections once a connection has been established, so you
+ * need to create a new ipcconn in order to start a new connection.
*/
-int flib_ipcconn_start(bool recordDemo);
+flib_ipcconn flib_ipcconn_create(bool recordDemo, const char *localPlayerName);
+
+uint16_t flib_ipcconn_port(flib_ipcconn ipc);
/**
- * Close the current IPC connection and/or stop listening for an incoming one.
- * This also discards all unread messages.
+ * Free resources, close sockets, and set the pointer to NULL.
*/
-void flib_ipcconn_close();
+void flib_ipcconn_destroy(flib_ipcconn *ipcptr);
/**
* Determine the current connection state
*/
-IpcConnState flib_ipcconn_state();
+IpcConnState flib_ipcconn_state(flib_ipcconn ipc);
/**
* Receive a single message (up to 255 bytes) and copy it into the data buffer.
@@ -58,7 +51,9 @@
* no further message is returned, to ensure you see all messages that were sent
* before the connection closed.
*/
-int flib_ipcconn_recv_message(void *data);
+int flib_ipcconn_recv_message(flib_ipcconn ipc, void *data);
+
+int flib_ipcconn_send_raw(flib_ipcconn ipc, void *data, size_t len);
/**
* Write a single message (up to 255 bytes) to the engine. This call blocks until the
@@ -67,43 +62,43 @@
* Calling this function in a state other than IPC_CONNECTED will fail immediately.
* Returns a negative value on failure.
*/
-int flib_ipcconn_send_message(void *data, size_t len);
+int flib_ipcconn_send_message(flib_ipcconn ipc, void *data, size_t len);
/**
* Convenience function for sending a 0-delimited string.
*/
-int flib_ipcconn_send_messagestr(char *data);
+int flib_ipcconn_send_messagestr(flib_ipcconn ipc, char *data);
/**
* Call regularly to allow background work to proceed
*/
-void flib_ipcconn_tick();
+void flib_ipcconn_tick(flib_ipcconn ipc);
/**
- * Get a demo record of the last connection. This should be called after
+ * Get a demo record of the connection. This should be called after
* the connection is closed and all messages have been received.
*
- * If demo recording was not enabled in the last call to flib_ipcconn_start(),
- * or if the recording failed for some reason, the buffer will be empty.
+ * If demo recording was not enabled, or if the recording failed for some reason,
+ * the buffer will be empty.
*
- * The buffer is only valid until the next call to flib_ipcconn_start() or
- * a call to flib_ipcconn_getsave() (save and demo records have some minor
- * differences, and those are performed directly on the buffer before returning it).
+ * The buffer is only valid until a call to flib_ipcconn_getsave(), since save
+ * and demo records have some minor differences, and those are performed directly
+ * on the buffer before returning it).
*/
-flib_constbuffer flib_ipcconn_getdemo();
+flib_constbuffer flib_ipcconn_getdemo(flib_ipcconn ipc);
/**
- * Get a savegame record of the last connection. This should be called after
+ * Get a savegame record of the connection. This should be called after
* the connection is closed and all messages have been received.
*
- * If demo recording was not enabled in the last call to flib_ipcconn_start(),
- * or if the recording failed for some reason, the buffer will be empty.
+ * If demo recording was not enabled, or if the recording failed for some reason,
+ * the buffer will be empty.
*
- * The buffer is only valid until the next call to flib_ipcconn_start() or
- * a call to flib_ipcconn_getdemo() (save and demo records have some minor
- * differences, and those are performed directly on the buffer before returning it).
+ * The buffer is only valid until a call to flib_ipcconn_getdemo(), since save
+ * and demo records have some minor differences, and those are performed directly
+ * on the buffer before returning it).
*/
-flib_constbuffer flib_ipcconn_getsave();
+flib_constbuffer flib_ipcconn_getsave(flib_ipcconn ipc);
#endif /* IPCCONN_H_ */
--- a/project_files/frontlib/nonblocksockets.c Sat Jun 02 22:54:09 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,76 +0,0 @@
-#include "nonblocksockets.h"
-#include "logging.h"
-#include <stdlib.h>
-
-static uint32_t get_peer_ip(TCPsocket sock) {
- IPaddress *addr = SDLNet_TCP_GetPeerAddress(sock);
- return SDLNet_Read32(&addr->host);
-}
-
-static bool connection_is_local(TCPsocket sock) {
- return get_peer_ip(sock) == (uint32_t)((127UL<<24)+1); // 127.0.0.1
-}
-
-void flib_nbsocket_close(NonBlockSocket *nbsockptr) {
- NonBlockSocket nbsock = *nbsockptr;
- if(nbsock!=NULL) {
- SDLNet_DelSocket(nbsock->sockset, (SDLNet_GenericSocket)nbsock->sock);
- SDLNet_TCP_Close(nbsock->sock);
- SDLNet_FreeSocketSet(nbsock->sockset);
- }
- free(nbsock);
- *nbsockptr = NULL;
-}
-
-NonBlockSocket flib_nbsocket_accept(TCPsocket listensocket, bool localOnly) {
- NonBlockSocket result = NULL;
- if(!listensocket) {
- flib_log_e("Attempt to accept a connection on a NULL socket.");
- return NULL;
- }
- while(result==NULL) {
- TCPsocket sock = SDLNet_TCP_Accept(listensocket);
- if(!sock) {
- // No incoming connections
- return NULL;
- }
- if(localOnly && !connection_is_local(sock)) {
- flib_log_i("Rejected nonlocal connection attempt from %s", flib_format_ip(get_peer_ip(sock)));
- SDLNet_TCP_Close(sock);
- } else {
- result = malloc(sizeof(_NonBlockSocket));
- if(result==NULL) {
- flib_log_e("Out of memory!");
- SDLNet_TCP_Close(sock);
- return NULL;
- }
- result->sock = sock;
- result->sockset = SDLNet_AllocSocketSet(1);
- if(result->sockset==NULL) {
- flib_log_e("Out of memory!");
- SDLNet_TCP_Close(sock);
- free(result);
- return NULL;
- }
- SDLNet_AddSocket(result->sockset, (SDLNet_GenericSocket)result->sock);
- }
- }
- return result;
-}
-
-int flib_nbsocket_recv(NonBlockSocket sock, void *data, int maxlen) {
- if(!sock) {
- flib_log_e("Attempt to receive on a NULL socket.");
- return -1;
- }
- int readySockets = SDLNet_CheckSockets(sock->sockset, 0);
- if(readySockets>0) {
- int size = SDLNet_TCP_Recv(sock->sock, data, maxlen);
- return size>0 ? size : -1;
- } else if(readySockets==0) {
- return 0;
- } else {
- flib_log_e("Error in select system call: %s", SDLNet_GetError());
- return -1;
- }
-}
--- a/project_files/frontlib/nonblocksockets.h Sat Jun 02 22:54:09 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,51 +0,0 @@
-/*
- * nonblocksockets.h
- *
- * Created on: 31.05.2012
- * Author: simmax
- */
-
-#ifndef NONBLOCKSOCKETS_H_
-#define NONBLOCKSOCKETS_H_
-
-#include <SDL_net.h>
-#include <stdbool.h>
-
-typedef struct {
- TCPsocket sock;
- SDLNet_SocketSet sockset;
-} _NonBlockSocket;
-
-typedef _NonBlockSocket *NonBlockSocket;
-
-/**
- * Close the indicated socket, free its memory and set it to NULL.
- * If the socket is already NULL, nothing happens.
- */
-void flib_nbsocket_close(NonBlockSocket *socket);
-
-/**
- * Try to accept a connection from a listening socket.
- * if localOnly is true, this will only accept connections which came from 127.0.0.1
- * Returns NULL if nothing can be accepted.
- */
-NonBlockSocket flib_nbsocket_accept(TCPsocket listensocket, bool localOnly);
-
-/**
- * Attempt to receive up to maxlen bytes from the socket, but does not
- * block if nothing is available.
- * Returns the ammount of data received, 0 if there was nothing to receive,
- * or a negative number if the connection was closed or an error occurred.
- */
-int flib_nbsocket_recv(NonBlockSocket sock, void *data, int maxlen);
-
-/**
- * We can't do a nonblocking send over SDL_net, so this function just forwards
- * to SDLNet_TCP_Send for convenience, which blocks until all data is sent or an
- * error occurs. The ammount of data actually sent is returned, negative value on error.
- */
-static inline int flib_nbsocket_blocksend(NonBlockSocket sock, void *data, int len) {
- return SDLNet_TCP_Send(sock->sock, data, len);
-}
-
-#endif /* NONBLOCKSOCKETS_H_ */
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/project_files/frontlib/socket.c Sun Jun 03 01:24:18 2012 +0200
@@ -0,0 +1,149 @@
+#include "socket.h"
+#include "logging.h"
+#include <stdlib.h>
+#include <SDL_net.h>
+#include <time.h>
+
+typedef struct _flib_tcpsocket {
+ TCPsocket sock;
+ SDLNet_SocketSet sockset;
+} _flib_tcpsocket;
+
+typedef struct _flib_acceptor {
+ TCPsocket sock;
+ uint16_t port;
+} _flib_acceptor;
+
+static uint32_t get_peer_ip(TCPsocket sock) {
+ IPaddress *addr = SDLNet_TCP_GetPeerAddress(sock);
+ return SDLNet_Read32(&addr->host);
+}
+
+static bool connection_is_local(TCPsocket sock) {
+ return get_peer_ip(sock) == (uint32_t)((127UL<<24)+1); // 127.0.0.1
+}
+
+flib_acceptor flib_acceptor_create(uint16_t port) {
+ flib_acceptor result = malloc(sizeof(_flib_acceptor));
+ if(!result) {
+ flib_log_e("Out of memory!");
+ return NULL;
+ }
+
+ IPaddress addr;
+ addr.host = INADDR_ANY;
+
+ if(port > 0) {
+ result->port = port;
+ SDLNet_Write16(port, &addr.port);
+ result->sock = SDLNet_TCP_Open(&addr);
+ if(result->sock) {
+ return result;
+ } else {
+ flib_log_e("Unable to listen on port %u: %s", port, SDLNet_GetError());
+ free(result);
+ return NULL;
+ }
+ } else {
+ /* SDL_net does not seem to have a way to listen on a random unused port
+ and find out which port that is, so let's try to find one ourselves. */
+ // TODO: Is socket binding fail-fast on all platforms?
+ srand(time(NULL));
+ rand();
+ for(int i=0; i<1000; i++) {
+ // IANA suggests using ports in the range 49152-65535 for things like this
+ result->port = 49152+(rand()%(65535-49152));
+ SDLNet_Write16(result->port, &addr.port);
+ result->sock = SDLNet_TCP_Open(&addr);
+ if(result->sock) {
+ return result;
+ } else {
+ flib_log_i("Unable to listen on port %u: %s", result->port, SDLNet_GetError());
+ }
+ }
+ flib_log_e("Unable to listen on a random unused port.");
+ free(result);
+ return NULL;
+ }
+}
+
+uint16_t flib_acceptor_listenport(flib_acceptor acceptor) {
+ return acceptor->port;
+}
+
+void flib_acceptor_close(flib_acceptor *acceptorptr) {
+ if(acceptorptr == NULL || *acceptorptr == NULL) {
+ return;
+ }
+ SDLNet_TCP_Close((*acceptorptr)->sock);
+ free(*acceptorptr);
+ *acceptorptr = NULL;
+}
+
+flib_tcpsocket flib_socket_accept(flib_acceptor acceptor, bool localOnly) {
+ flib_tcpsocket result = NULL;
+ if(!acceptor) {
+ return NULL;
+ }
+ while(result==NULL) {
+ TCPsocket sock = SDLNet_TCP_Accept(acceptor->sock);
+ if(!sock) {
+ // No incoming connections
+ return NULL;
+ }
+ if(localOnly && !connection_is_local(sock)) {
+ flib_log_i("Rejected nonlocal connection attempt from %s", flib_format_ip(get_peer_ip(sock)));
+ SDLNet_TCP_Close(sock);
+ } else {
+ result = malloc(sizeof(_flib_tcpsocket));
+ if(result==NULL) {
+ flib_log_e("Out of memory!");
+ SDLNet_TCP_Close(sock);
+ return NULL;
+ }
+ result->sock = sock;
+ result->sockset = SDLNet_AllocSocketSet(1);
+ if(result->sockset==NULL) {
+ flib_log_e("Out of memory!");
+ SDLNet_TCP_Close(sock);
+ free(result);
+ return NULL;
+ }
+ SDLNet_AddSocket(result->sockset, (SDLNet_GenericSocket)result->sock);
+ }
+ }
+ return result;
+}
+
+void flib_socket_close(flib_tcpsocket *sockptr) {
+ if(sockptr==NULL || *sockptr == NULL) {
+ return;
+ }
+ flib_tcpsocket sock = *sockptr;
+ SDLNet_DelSocket(sock->sockset, (SDLNet_GenericSocket)sock->sock);
+ SDLNet_TCP_Close(sock->sock);
+ SDLNet_FreeSocketSet(sock->sockset);
+ free(sock);
+ *sockptr = NULL;
+}
+
+int flib_socket_nbrecv(flib_tcpsocket sock, void *data, int maxlen) {
+ if(!sock) {
+ flib_log_e("Attempt to receive on a NULL socket.");
+ return -1;
+ }
+ int readySockets = SDLNet_CheckSockets(sock->sockset, 0);
+ if(readySockets>0) {
+ int size = SDLNet_TCP_Recv(sock->sock, data, maxlen);
+ return size>0 ? size : -1;
+ } else if(readySockets==0) {
+ return 0;
+ } else {
+ flib_log_e("Error in select system call: %s", SDLNet_GetError());
+ return -1;
+ }
+}
+
+int flib_socket_send(flib_tcpsocket sock, void *data, int len) {
+ return SDLNet_TCP_Send(sock->sock, data, len);
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/project_files/frontlib/socket.h Sun Jun 03 01:24:18 2012 +0200
@@ -0,0 +1,72 @@
+/*
+ * Sockets for TCP networking.
+ *
+ * This layer offers some functionality over what SDL_net offers directly: listening
+ * sockets (called acceptors here) can be bound to port 0, which will make them listen
+ * on a random unused port, if one can be found. To support this feature, you can also
+ * query the local port that an acceptor is listening on.
+ *
+ * Further, we support nonblocking reads and writes here. The writes are buffered (TODO),
+ * so that all data will be accepted, and you can configure a maximum buffer size
+ * where the connection will be terminated.
+ *
+ * In order to ensure buffered data is actually sent out, you should regularly call
+ * the tick function on your sockets.
+ */
+
+#ifndef SOCKET_H_
+#define SOCKET_H_
+
+#include <stdbool.h>
+#include <stdint.h>
+
+struct _flib_tcpsocket;
+typedef struct _flib_tcpsocket *flib_tcpsocket;
+
+struct _flib_acceptor;
+typedef struct _flib_acceptor *flib_acceptor;
+
+/**
+ * Create a new acceptor which will listen for incoming TCP connections
+ * on the given port. If port is 0, this will listen on a random
+ * unused port which can then be queried with flib_acceptor_listenport.
+ *
+ * Can return NULL on error.
+ */
+flib_acceptor flib_acceptor_create(uint16_t port);
+
+/**
+ * Return the port on which the acceptor is listening.
+ */
+uint16_t flib_acceptor_listenport(flib_acceptor acceptor);
+
+/**
+ * Close the acceptor, free its memory and set it to NULL.
+ * If the acceptor is already NULL, nothing happens.
+ */
+void flib_acceptor_close(flib_acceptor *acceptorptr);
+
+/**
+ * Try to accept a connection from an acceptor (listening socket).
+ * if localOnly is true, this will only accept connections which came from 127.0.0.1
+ * Returns NULL if nothing can be accepted.
+ */
+flib_tcpsocket flib_socket_accept(flib_acceptor acceptor, bool localOnly);
+
+/**
+ * Close the socket, free its memory and set it to NULL.
+ * If the socket is already NULL, nothing happens.
+ */
+void flib_socket_close(flib_tcpsocket *socket);
+
+/**
+ * Attempt to receive up to maxlen bytes from the socket, but does not
+ * block if nothing is available.
+ * Returns the ammount of data received, 0 if there was nothing to receive,
+ * or a negative number if the connection was closed or an error occurred.
+ */
+int flib_socket_nbrecv(flib_tcpsocket sock, void *data, int maxlen);
+
+int flib_socket_send(flib_tcpsocket sock, void *data, int len);
+
+#endif /* SOCKET_H_ */