Hook up Ethernet JS API to SheepShaver

Mostly a matter of bridging the Basilisk II ethernet APIs to
SheepShaver's, similar to ether_unix.cpp. Two gotchas that were
encountered:
- SheepShaver's PRAM is offset by 0x1300 bytes, so toggling of the
  preferences to enable AppleTalk at boot time had to be adjusted.
- We can end up trying to process an Ethernet packet before the driver
  is initialized, which leads to a segfault. Add a guard for
  ether_driver_opened (and in that case drop the packet on the floor).

This is enough to make Marathon network play work under System 7.5.3,
but it does not work under Mac OS 9.

Updates mihaip/infinite-mac#34

BasiliskII/src/CrossPlatform/ether_helpers.h

@@ -0,0 +1,34 @@
+#ifndef ETHER_HELPERS_H
+#define ETHER_HELPERS_H
+
+/*
+ *  Check whether Ethernet address is AppleTalk or Ethernet broadcast address
+ */
+
+static inline bool is_apple_talk_broadcast(uint8 *p) {
+  return p[0] == 0x09 && p[1] == 0x00 && p[2] == 0x07 && p[3] == 0xff &&
+         p[4] == 0xff && p[5] == 0xff;
+}
+
+static inline bool is_ethernet_broadcast(uint8 *p) {
+  return p[0] == 0xff && p[1] == 0xff && p[2] == 0xff && p[3] == 0xff &&
+         p[4] == 0xff && p[5] == 0xff;
+}
+
+static void enable_apple_talk_in_pram(uint8 *XPRAM) {
+  // node ID hint for printer port (AppleTalk)
+  XPRAM[0x12] = 0x01;
+  // serial ports config bits: 4-7 A, 0-3 B
+  // 	useFree   0 Use undefined
+  // 	useATalk  1 AppleTalk
+  // 	useAsync  2 Async
+  // 	useExtClk 3 externally clocked
+  XPRAM[0x13] = 0x20;
+  // AppleTalk Zone name ("*")
+  XPRAM[0xbd] = 0x01;
+  XPRAM[0xbe] = 0x2a;
+  // AppleTalk Network Number
+  XPRAM[0xde] = 0xff;
+}
+
+#endif /* ETHER_HELPERS_H */

BasiliskII/src/Unix/JS/ether_js.cpp

@@ -7,12 +7,25 @@
 #include "cpu_emulation.h"
 #include "ether.h"
 #include "ether_defs.h"
+#include "ether_helpers.h"
 #include "macos_util.h"
 #include "main.h"
+#include "prefs.h"
 
 #define DEBUG 0
 #include "debug.h"
 
+#ifdef SHEEPSHAVER
+static bool net_open = false;  // Flag: initialization succeeded, network device open
+static uint8 ether_addr[6];    // Our Ethernet address
+
+// Error codes
+enum { eMultiErr = -91, eLenErr = -92, lapProtErr = -94, excessCollsns = -95 };
+
+#define ether_wds_to_buffer ether_msgb_to_buffer
+
+#endif
+
 static const uint8 GENERATED_ETHER_ADDR_PREFIX = 0xb2;
 
 // Attached network protocols, maps protocol type to MacOS handler address
@@ -25,6 +38,8 @@ static void ether_addr_to_str(uint8* ether_addr, char* ether_addr_str) {
           ether_addr[2], ether_addr[3], ether_addr[4], ether_addr[5]);
 }
 
+#ifndef SHEEPSHAVER
+
 // Dispatch packet to protocol handler
 static void ether_dispatch_packet(uint32 p, uint32 length) {
   // Get packet type
@@ -64,6 +79,8 @@ static void ether_dispatch_packet(uint32 p, uint32 length) {
   Execute68k(handler, &r);
 }
 
+#endif
+
 bool ether_init(void) {
   // Construct random Ethernet address. JS has access to a better random
   // number generator, use that to seed.
@@ -165,7 +182,77 @@ void EtherInterrupt(void) {
     if (length < 14) {
       return;
     }
-
+#ifdef SHEEPSHAVER
+    if (!ether_driver_opened) {
+      // We can't dispatch packets before the ethernet driver is initialized
+      // (ether_dispatch_packet_tvect is not initialized yet), don't do anything
+      // for now.
+      D(bug("Dropping Ethernet packet of %d bytes, driver has not been opened yet\n", length));
+      continue;
+    }
+#endif
     ether_dispatch_packet(packet, length);
   }
 }
+
+// SheepShaver glue
+#ifdef SHEEPSHAVER
+
+void EtherInit(void) {
+  net_open = false;
+
+  if (PrefsFindBool("nonet")) {
+    return;
+  }
+
+  net_open = ether_init();
+}
+
+void EtherExit(void) {
+  ether_exit();
+  net_open = false;
+}
+
+void AO_get_ethernet_address(uint32 arg) {
+  uint8* addr = Mac2HostAddr(arg);
+  if (net_open)
+    OTCopy48BitAddress(ether_addr, addr);
+  else {
+    addr[0] = 0x12;
+    addr[1] = 0x34;
+    addr[2] = 0x56;
+    addr[3] = 0x78;
+    addr[4] = 0x9a;
+    addr[5] = 0xbc;
+  }
+  D(bug("AO_get_ethernet_address: got address %02x%02x%02x%02x%02x%02x\n", addr[0], addr[1],
+        addr[2], addr[3], addr[4], addr[5]));
+}
+
+void AO_enable_multicast(uint32 addr) {
+  // No-op
+}
+
+void AO_disable_multicast(uint32 addr) {
+  // No-op
+}
+
+void AO_transmit_packet(uint32 mp) {
+  if (net_open) {
+    switch (ether_write(mp)) {
+      case noErr:
+        num_tx_packets++;
+        break;
+      case excessCollsns:
+        num_tx_buffer_full++;
+        break;
+    }
+  }
+}
+
+void EtherIRQ(void) {
+  num_ether_irq++;
+  EtherInterrupt();
+}
+
+#endif  // SHEEPSHAVER

BasiliskII/src/ether.cpp

@@ -46,6 +46,7 @@
 #include "prefs.h"
 #include "ether.h"
 #include "ether_defs.h"
+#include "ether_helpers.h"
 
 #ifndef NO_STD_NAMESPACE
 using std::map;

BasiliskII/src/include/ether.h

@@ -93,21 +93,4 @@ static inline int ether_wds_to_buffer(uint32 wds, uint8 *p)
 	return len;
 }
 
-/*
- *  Check whether Ethernet address is AppleTalk or Ethernet broadcast address
- */
-
-static inline bool is_apple_talk_broadcast(uint8 *p)
-{
-	return p[0] == 0x09 && p[1] == 0x00 && p[2] == 0x07
-	    && p[3] == 0xff && p[4] == 0xff && p[5] == 0xff;
-}
-
-static inline bool is_ethernet_broadcast(uint8 *p)
-{
-	return p[0] == 0xff && p[1] == 0xff && p[2] == 0xff
-	    && p[3] == 0xff && p[4] == 0xff && p[5] == 0xff;
-}
-
-
 #endif

BasiliskII/src/main.cpp

@@ -32,6 +32,7 @@
 #include "video.h"
 #include "serial.h"
 #include "ether.h"
+#include "ether_helpers.h"
 #include "clip.h"
 #include "adb.h"
 #include "rom_patches.h"
@@ -133,19 +134,7 @@ bool InitAll(const char *vmdir)
 	}
 
 	if (PrefsFindBool("appletalk")) {
-		// node ID hint for printer port (AppleTalk)
-		XPRAM[0x12] = 0x01;
-		// serial ports config bits: 4-7 A, 0-3 B
-		// 	useFree   0 Use undefined
-		// 	useATalk  1 AppleTalk
-		// 	useAsync  2 Async
-		// 	useExtClk 3 externally clocked
-		XPRAM[0x13] = 0x20;
-		// AppleTalk Zone name ("*")
-		XPRAM[0xbd] = 0x01;
-		XPRAM[0xbe] = 0x2a;
-		// AppleTalk Network Number
-		XPRAM[0xde] = 0xff;
+		enable_apple_talk_in_pram(XPRAM);
 	}
 
 	// Set boot volume

SheepShaver/src/CrossPlatform/ether_helpers.h

@@ -0,0 +1 @@
+../../../BasiliskII/src/CrossPlatform/ether_helpers.h

SheepShaver/src/Unix/JS/ether_js.cpp

@@ -0,0 +1 @@
+../../../../BasiliskII/src/Unix/JS/ether_js.cpp

SheepShaver/src/Unix/configure.ac

@@ -819,7 +819,7 @@ if [[ "x$WANT_EMSCRIPTEN" = "xyes" ]]; then
   VIDEOSRCS="JS/video_js.cpp SpookyV2.cpp"
   SERIALSRC=../dummy/serial_dummy.cpp
   SCSISRC=../dummy/scsi_dummy.cpp
-  ETHERSRC=../dummy/ether_dummy.cpp
+  ETHERSRC=JS/ether_js.cpp
   AUDIOSRC=JS/audio_js.cpp
   EXTRASYSSRCS="$EXTRASYSSRCS JS/input_js.cpp JS/clip_js.cpp"
   AC_DEFINE(EMSCRIPTEN, 1, [Define if targeting Emscripten.])

SheepShaver/src/main.cpp

@@ -37,6 +37,7 @@
 #include "video.h"
 #include "audio.h"
 #include "ether.h"
+#include "ether_helpers.h"
 #include "serial.h"
 #include "clip.h"
 #include "extfs.h"
@@ -106,6 +107,10 @@ bool InitAll(const char *vmdir)
 		XPRAM[0x138a] = 0x25;	// Use PPC memory manager ("Modern Memory Manager")
 	}
 
+	if (PrefsFindBool("appletalk")) {
+		enable_apple_talk_in_pram(XPRAM + 0x1300);
+	}
+
 	// Set boot volume
 	int16 i16 = PrefsFindInt32("bootdrive");
 	XPRAM[0x1378] = i16 >> 8;

SheepShaver/src/prefs_items.cpp

@@ -73,6 +73,7 @@ prefs_desc common_prefs_items[] = {
 	{"title", TYPE_STRING, false,	"window title"},
 	{"sound_buffer", TYPE_INT32, false,	"sound buffer length"},
 	{"name_encoding", TYPE_INT32, false,	"file name encoding"},
+	{"appletalk", TYPE_BOOLEAN, false, "enable AppleTalk in default PRAM"},
 	{"jsfrequentreadinput", TYPE_BOOLEAN, false, "Read JS input frequently (multiple times per tick) to reduce latency"},
 	{NULL, TYPE_END, false, NULL} // End of list
 };