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FEX-Emu · Jan 28, 2025 · d85101b · d85101b
1 parent 83ce2d8
commit d85101b
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Showing 3 changed files with 95 additions and 54 deletions.
diff --git a/Source/Tools/LinuxEmulation/LinuxSyscalls/GdbServer.cpp b/Source/Tools/LinuxEmulation/LinuxSyscalls/GdbServer.cpp
@@ -203,7 +203,12 @@ fextl::string GdbServer::ReadPacket() {
       break;
     case '}': // escape char
     {
-      auto escaped = CommsStream.get();
+      Utils::NetStream::ReturnGet escaped;
+
+      do {
+        escaped = CommsStream.get();
+      } while (!escaped.HasData() && !escaped.HasHangup());
+
       if (escaped.HasData()) {
         packet.push_back(escaped.GetData() ^ 0x20);
       } else {
@@ -214,7 +219,7 @@ fextl::string GdbServer::ReadPacket() {
     case '#': // end of packet
     {
       char hexString[3] = {0, 0, 0};
-      CommsStream.read(hexString, 2);
+      CommsStream.read(hexString, 2, true);
       int expected_checksum = std::strtoul(hexString, nullptr, 16);
 
       if (calculateChecksum(packet) == expected_checksum) {
@@ -1395,45 +1400,47 @@ void GdbServer::GdbServerLoop() {
 
     HandledPacketType response {};
 
-    // Outer server loop. Handles packet start, ACK/NAK and break
-    Utils::NetStream::ReturnGet c;
-    while (!CoreShuttingDown.load() && (c = CommsStream.get()).HasData()) {
-      switch (c.GetData()) {
-      case '$': {
-        auto packet = ReadPacket();
-        response = ProcessPacket(packet);
-        SendPacketPair(response);
-        if (response.TypeResponse == HandledPacketType::TYPE_UNKNOWN) {
-          LogMan::Msg::DFmt("Unknown packet {}", packet);
+    while (!CoreShuttingDown.load()) {
+      // Outer server loop. Handles packet start, ACK/NAK and break
+      Utils::NetStream::ReturnGet c;
+      while ((c = CommsStream.get()).HasData()) {
+        switch (c.GetData()) {
+        case '$': {
+          auto packet = ReadPacket();
+          response = ProcessPacket(packet);
+          SendPacketPair(response);
+          if (response.TypeResponse == HandledPacketType::TYPE_UNKNOWN) {
+            LogMan::Msg::DFmt("Unknown packet {}", packet);
+          }
+          break;
         }
-        break;
-      }
-      case '+':
-        // ACK, do nothing.
-        break;
-      case '-':
-        // NAK, Resend requested
-        {
-          std::lock_guard lk(sendMutex);
-          SendPacket(response.Response);
+        case '+':
+          // ACK, do nothing.
+          break;
+        case '-':
+          // NAK, Resend requested
+          {
+            std::lock_guard lk(sendMutex);
+            SendPacket(response.Response);
+          }
+          break;
+        case '\x03': { // ASCII EOT
+          SyscallHandler->TM.Pause();
+          fextl::string str = fextl::fmt::format("T02thread:{:02x};", getpid());
+          if (LibraryMapChanged) {
+            // If libraries have changed then let gdb know
+            str += "library:1;";
+          }
+          SendPacketPair({std::move(str), HandledPacketType::TYPE_ACK});
+          break;
         }
-        break;
-      case '\x03': { // ASCII EOT
-        SyscallHandler->TM.Pause();
-        fextl::string str = fextl::fmt::format("T02thread:{:02x};", getpid());
-        if (LibraryMapChanged) {
-          // If libraries have changed then let gdb know
-          str += "library:1;";
+        default: LogMan::Msg::DFmt("GdbServer: Unexpected byte {} ({:02x})", c.GetData(), c.GetData());
         }
-        SendPacketPair({std::move(str), HandledPacketType::TYPE_ACK});
-        break;
-      }
-      default: LogMan::Msg::DFmt("GdbServer: Unexpected byte {} ({:02x})", c.GetData(), c.GetData());
       }
-    }
 
-    if (c.HasHangup()) {
-      break;
+      if (c.HasHangup()) {
+        break;
+      }
     }
 
     {

diff --git a/Source/Tools/LinuxEmulation/LinuxSyscalls/NetStream.cpp b/Source/Tools/LinuxEmulation/LinuxSyscalls/NetStream.cpp
@@ -5,11 +5,18 @@
 #include <FEXCore/Utils/LogManager.h>
 
 #include <cstring>
+#include <sys/eventfd.h>
 #include <sys/socket.h>
 #include <poll.h>
 #include <unistd.h>
 
 namespace FEX::Utils {
+
+NetStream::NetStream()
+  : receive_buffer(1500) {
+  eventfd = ::eventfd(0, EFD_CLOEXEC);
+}
+
 NetStream::ReturnGet NetStream::get() {
   if (read_offset != receive_buffer.size() && read_offset != receive_offset) {
     auto Result = receive_buffer.at(read_offset);
@@ -22,43 +29,67 @@ NetStream::ReturnGet NetStream::get() {
     receive_offset = 0;
   }
 
-  struct pollfd pfd {
-    .fd = socketfd, .events = POLLIN, .revents = 0,
+  struct pollfd pfds[2] = {
+    {
+      .fd = socketfd,
+      .events = POLLIN,
+      .revents = 0,
+    },
+
+    {
+      .fd = eventfd,
+      .events = POLLIN,
+      .revents = 0,
+    },
   };
 
-  auto Result = ppoll(&pfd, 1, nullptr, nullptr);
+  auto Result = poll(pfds, sizeof(pfds), -1);
   if (Result > 0) {
-    if (pfd.revents & POLLHUP) {
-      return NetStream::ReturnGet {true};
-    }
+    for (auto& pfd : pfds) {
+      if (pfd.fd == eventfd) {
+        // Interrupted by eventfd.
+        uint64_t data;
+        ::read(pfd.fd, &data, sizeof(data));
+        break;
+      }
+
+      if (pfd.revents & POLLHUP) {
+        return NetStream::ReturnGet {true};
+      }
 
-    const auto remaining_size = receive_buffer.size() - receive_offset;
-    Result = ::recv(socketfd, &receive_buffer.at(receive_offset), remaining_size, 0);
-    if (Result > 0) {
-      receive_offset += Result;
-      auto Result = receive_buffer.at(read_offset);
-      ++read_offset;
-      return NetStream::ReturnGet {Result};
+      const auto remaining_size = receive_buffer.size() - receive_offset;
+      Result = ::recv(socketfd, &receive_buffer.at(receive_offset), remaining_size, 0);
+      if (Result > 0) {
+        receive_offset += Result;
+        auto Result = receive_buffer.at(read_offset);
+        ++read_offset;
+        return NetStream::ReturnGet {Result};
+      }
     }
   }
 
   return NetStream::ReturnGet {false};
 }
 
-size_t NetStream::read(char* buf, size_t size) {
+size_t NetStream::read(char* buf, size_t size, bool ContinueOnInterrupt) {
   size_t Read {};
   while (Read < size) {
     auto Result = get();
     if (Result.HasData()) {
       buf[Read] = Result.GetData();
       ++Read;
-    } else {
+    } else if ((!Result.HasData() && !ContinueOnInterrupt) || Result.HasHangup()) {
       return Read;
     }
   }
   return Read;
 }
 
+void NetStream::InterruptReader() {
+  uint64_t data {1};
+  ::write(eventfd, &data, sizeof(data));
+}
+
 bool NetStream::SendPacket(const fextl::string& packet) {
   size_t Total {};
   while (Total < packet.size()) {

diff --git a/Source/Tools/LinuxEmulation/LinuxSyscalls/NetStream.h b/Source/Tools/LinuxEmulation/LinuxSyscalls/NetStream.h
@@ -11,8 +11,7 @@
 namespace FEX::Utils {
 class NetStream final {
 public:
-  NetStream()
-    : receive_buffer(1500) {}
+  NetStream();
 
   void OpenSocket(int _socketfd) {
     socketfd = _socketfd;
@@ -37,12 +36,16 @@ class NetStream final {
       return std::get<char>(*this);
     }
   };
+
   ReturnGet get();
-  size_t read(char* buf, size_t size);
+  size_t read(char* buf, size_t size, bool ContinueOnInterrupt);
+
+  void InterruptReader();
 
   bool SendPacket(const fextl::string& packet);
 private:
   int socketfd {-1};
+  int eventfd {-1};
   size_t read_offset {};
   size_t receive_offset {};
   fextl::vector<char> receive_buffer;