fix windows compile; add comments

cnping.c

@@ -62,8 +62,6 @@ struct PingHost
 	struct PingHost* next;
 };
 
-unsigned frames = 0;
-unsigned long iframeno = 0;
 short screenx, screeny;
 float GuiYScaleFactor;
 int GuiYscaleFactorIsConstant;
@@ -74,6 +72,8 @@ uint8_t pattern[8] = {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF};
 #define TIMEOUT 4
 
 struct PingData * PingData = NULL;
+
+// count of hosts to ping - represents size of PingData and number of elements in pinghostList
 unsigned int pinghostListSize = 0;
 
 
@@ -692,6 +692,8 @@ int main( int argc, const char ** argv )
 	double SecToWait;
 	double frameperiodseconds;
 	const char * device = NULL;
+
+	// linked list of all hosts that should be pinged
 	struct PingHost * pinghostList = NULL;
 	pinghostListSize = 0;
 
@@ -864,6 +866,8 @@ int main( int argc, const char ** argv )
 
 	frameperiodseconds = fmin(.2, fmax(.03, pingperiodseconds) );
 
+	unsigned frames = 0;
+	unsigned long iframeno = 0;
 	while(1)
 	{
 		iframeno++;

ping.c

@@ -36,6 +36,12 @@ int using_regular_ping;
 
 #include "rawdraw/os_generic.h"
 
+// used to pack arguments for windows ping threads
+struct WindowsPingArgs
+{
+	struct PreparedPing* pp;
+	HANDLE icmpHandle;
+};
 
 
 #define MAX_PING_SIZE 16384
@@ -84,27 +90,29 @@ void listener( struct PreparedPing* pp )
 	return;
 }
 
-static HANDLE pinghandles[PINGTHREADS];
-
 static void * pingerthread( void * v )
 {
 	uint8_t ping_payload[MAX_PING_SIZE];
 
-	HANDLE ih = *((HANDLE*)v);
+	// copy arguments and free struct
+	struct WindowsPingArgs* args = (struct WindowsPingArgs*) v;
+	struct PreparedPing* pp = args->pp;
+	HANDLE ih = args->icmpHandle;
+	free(args);
 
 	int timeout_ms = pingperiodseconds * (PINGTHREADS-1) * 1000;
 	while(1)
 	{
 		OGLockSema( s_ping );
-		int rl = load_ping_packet( ping_payload, sizeof( ping_payload ) );
+		int rl = load_ping_packet( ping_payload, sizeof( ping_payload ), PingData + pp->pingHostId );
 		struct repl_t
 		{
 			ICMP_ECHO_REPLY rply;
 			uint8_t err_data[16384];
 		} repl;
 
 		DWORD res = IcmpSendEcho( ih,
-			((struct sockaddr_in*) &psaddr)->sin_addr.s_addr, ping_payload, rl,
+			((struct sockaddr_in*) &pp->psaddr)->sin_addr.s_addr, ping_payload, rl,
 			0, &repl, sizeof( repl ),
 			timeout_ms );
 		int err;
@@ -124,7 +132,7 @@ static void * pingerthread( void * v )
 		}
 		if( res )
 		{
-			display( repl.rply.Data, rl );
+			display( repl.rply.Data, rl, pp->pingHostId );
 		}
 		OGUnlockSema( s_disp );
 	}
@@ -149,14 +157,17 @@ void singleping( struct PreparedPing* pp )
 		//Launch pinger threads
 		for( i = 0; i < PINGTHREADS; i++ )
 		{
-			HANDLE ih = pinghandles[i] = IcmpCreateFile();
+			HANDLE ih = IcmpCreateFile();
 			if( ih == INVALID_HANDLE_VALUE )
 			{
 				ERRM( "Cannot create ICMP thread %d\n", i );
 				exit( 0 );
 			}
 
-			OGCreateThread( pingerthread, &pinghandles[i] );
+			struct WindowsPingArgs* args = (struct WindowsPingArgs*) malloc(sizeof(struct WindowsPingArgs));
+			args->pp = pp;
+			args->icmpHandle = ih;
+			OGCreateThread( pingerthread, args );
 		}
 	}
 	//This function is executed as a thread after setup.
@@ -182,14 +193,17 @@ void ping( struct PreparedPing* pp )
 	//Launch pinger threads
 	for( i = 0; i < PINGTHREADS; i++ )
 	{
-		HANDLE ih = pinghandles[i] = IcmpCreateFile();
+		HANDLE ih = IcmpCreateFile();
 		if( ih == INVALID_HANDLE_VALUE )
 		{
 			ERRM( "Cannot create ICMP thread %d\n", i );
 			exit( 0 );
 		}
 
-		OGCreateThread( pingerthread, &pinghandles[i] );
+		struct WindowsPingArgs* args = (struct WindowsPingArgs*) malloc(sizeof(struct WindowsPingArgs));
+		args->pp = pp;
+		args->icmpHandle = ih;
+		OGCreateThread( pingerthread, args );
 	}
 	//This function is executed as a thread after setup.
 

ping.h

@@ -24,12 +24,19 @@
 
 struct PreparedPing
 {
+	// socket for sending the pings
 	int fd;
+
+	// the number of this host -> used to access the PingData array
 	int pingHostId;
+
+	// address to send the pings to
 	struct sockaddr_in6 psaddr;
+	// size of psaddr
 	socklen_t psaddr_len;
 };
 
+// meassured ping data of one host. This is the meassured data cnping displays
 struct PingData
 {
 	double PingSendTimes [PINGCYCLEWIDTH];
@@ -39,9 +46,13 @@ struct PingData
 	double globinterval, globlast;
 	uint64_t globalrx;
 	uint64_t globallost;
+
+	// pointer to the related prepared ping so it can be freed at exit
 	struct PreparedPing* pp;
 };
 
+// captured ping data - This is an array that get allocated with the size of pinghostListSize
+// each Ping thread should use pingHostId as offset into this array
 extern struct PingData * PingData;
 
 unsigned short checksum(const unsigned char *b, uint16_t len);
@@ -61,6 +72,8 @@ void singleping( struct PreparedPing* pp ); // If using this, must call ping_set
 //If pingperiodseconds = -1, run ping/do_pinger once and exit.
 extern float pingperiodseconds;
 extern int ping_failed_to_send;
+
+// resolvs the hostname and prepares the socket. Might return NULL on error
 struct PreparedPing* ping_setup(const char * strhost, const char * device);