[Lldb-commits] [lldb] [lldb] Have lldb-server assign ports to children in platform mode (PR #88845)

[Anthony Ha via lldb-commits]

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@@ -301,13 +294,31 @@ int main_platform(int argc, char *argv[]) {
       exit(socket_error);
     }
     printf("Connection established.\n");
+
+    std::optional<uint16_t> port = 0;
     if (g_server) {
       // Collect child zombie processes.
 #if !defined(_WIN32)
-      while (waitpid(-1, nullptr, WNOHANG) > 0)
-        ;
+      auto waitResult = waitpid(-1, nullptr, WNOHANG);
+      while (waitResult > 0) {
+        // waitResult is the child pid
+        gdbserver_portmap.FreePortForProcess(waitResult);
+        waitResult = waitpid(-1, nullptr, WNOHANG);
+      }
 #endif
-      if (fork()) {
+      llvm::Expected<uint16_t> available_port =
+          gdbserver_portmap.GetNextAvailablePort();
+      if (available_port)
+        port = *available_port;
+
+      else {
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Awfa wrote:

In the else branch, the connection to the platform will just be dropped, and an error printed to stderr.

This is a recoverable error in the sense that when a child platform process dies, a port will become available again - so it's desirable not to crash `lldb-server`.

https://github.com/llvm/llvm-project/pull/88845