Impl breakpoints (pretty much draft)

Breakpoints work somehow, but overstep 1 instruction. Needs to be fixed.

1 files changed, 44 insertions, 13 deletions

diff --git a/emulator.cpp b/emulator.cpp
index 1c8c6f9..5228231 100644
--- a/emulator.cpp
+++ b/emulator.cpp
@@ -31,6 +31,7 @@
 
 static constexpr struct timespec kOneMillisecond{0, 1000000};
 char msg_buf[MESSAGE_BUFFER_SIZE];
+M68KDebuggingControl g_m68k_debug{};
 
 static int set_socket_reuseaddr(int socket_fd)
 {
@@ -116,9 +117,19 @@ static std::string CreateResponse(
         return "1";
     } else if (packet.type == PacketType::kInterrupt) {
         return "OK";
+    } else if (packet.type == PacketType::kSetBreakpoint) {
+        const auto * const bkpt_data =
+            static_cast<const PacketDataBreakpoint*>(packet.data.get());
+        m68k_debug.SetBreakpoint(bkpt_data->type, bkpt_data->offset, bkpt_data->length);
+        return "OK";
+    } else if (packet.type == PacketType::kDeleteBreakpoint) {
+        const auto * const bkpt_data =
+            static_cast<const PacketDataBreakpoint*>(packet.data.get());
+        m68k_debug.RemoveBreakpoint(bkpt_data->type, bkpt_data->offset, bkpt_data->length);
+        return "OK";
     } else if (packet.type == PacketType::kReadMemory) {
         const auto * const data =
-            reinterpret_cast<const PacketDataReadMemory*>(packet.data.get());
+            static_cast<const PacketDataReadMemory*>(packet.data.get());
         const uint32_t offset = data->offset;
         const uint32_t length = data->length;
         auto ret_data = std::string(length * 2, '\0');
@@ -129,7 +140,7 @@ static std::string CreateResponse(
         return ret_data;
     } else if (packet.type == PacketType::kWriteMemory) {
         const auto * const packet_data =
-            reinterpret_cast<const PacketDataWriteMemory*>(packet.data.get());
+            static_cast<const PacketDataWriteMemory*>(packet.data.get());
         const uint32_t offset = packet_data->offset;
         const uint32_t length = packet_data->length;
         const auto write_data = packet_data->data;
@@ -194,17 +205,30 @@ static void make_hex(char* buff, unsigned int pc, unsigned int length)
     }
 }
 
+// TODO m68k_set_illg_instr_callback for true software breakpoint "4e4f"
+
 void m68k_instr_callback(int pc)
 {
-    if (!DEBUG_TRACE_INSTRUCTIONS)
-        return;
-    char buff[100];
-    unsigned int instr_size =
-        m68k_disassemble(buff, pc, M68K_CPU_TYPE_68000);
-    char buff2[100];
-    make_hex(buff2, pc, instr_size);
-    printf("  %08X: %-20s: %s\n", pc, buff2, buff);
-    fflush(stdout);
+    const auto it = std::find_if(
+            code_bkpts.begin(),
+            code_bkpts.end(),
+            [&](const Breakpoint& b) { return b.offset == static_cast<uint32_t>(pc); });
+    if (it != code_bkpts.end()) {
+        g_m68k_debug.SetRunning(false);
+        g_m68k_debug.RaiseBreakpoint();
+        m68k_end_timeslice();
+        printf("Breakpoint!\n");
+        // TODO notify GDB somehow that breakpoint has been hit
+    }
+    if (DEBUG_TRACE_INSTRUCTIONS) {
+        char buff[100];
+        unsigned int instr_size =
+            m68k_disassemble(buff, pc, M68K_CPU_TYPE_68000);
+        char buff2[100];
+        make_hex(buff2, pc, instr_size);
+        printf("  %08X: %-20s: %s\n", pc, buff2, buff);
+        fflush(stdout);
+    }
 }
 
 void ParseAndReact(
@@ -291,6 +315,14 @@ int emulator(M68KDebuggingControl& m68k_debug)
             if (m68k_debug.IsRunning()) {
                 m68k_execute(1000);
             }
+            if (m68k_debug.HasBreakpoint()) {
+                m68k_debug.ResetPendingBreakpoint();
+                    const auto response =
+                        exchange_ctx.WrapDataToSend("S05");
+                    printf("-> \"%s\"\n", response.c_str());
+                    if (send(conn_fd, &response[0], response.length(), 0) == -1)
+                        perror("Send failed (response)");
+            }
             // TODO turn off O_NONBLOCK and poll instead of sleep, only use
             // nonlock when freerunning
             clock_nanosleep(CLOCK_MONOTONIC, 0, &kOneMillisecond, nullptr);
@@ -323,8 +355,7 @@ int main(int argc, char* argv[])
     m68k_set_cpu_type(M68K_CPU_TYPE_68000);
     m68k_pulse_reset();
 
-    M68KDebuggingControl m68k_debug{};
-    emulator(m68k_debug);
+    emulator(g_m68k_debug);
     while (0)
     {
         // Values to execute determine the interleave rate.