From 2901029cae4cf8d9db67d5b3486c4db2935af1c9 Mon Sep 17 00:00:00 2001
From: Dennis Bonke <admin@dennisbonke.com>
Date: Mon, 23 Sep 2024 11:56:28 +0200
Subject: [PATCH] posix: Add sysconf request

---
 posix/subsystem/src/requests.cpp | 50 ++++++++++++++++++++++++++++++++
 protocols/posix/posix.bragi      | 11 +++++++
 2 files changed, 61 insertions(+)

diff --git a/posix/subsystem/src/requests.cpp b/posix/subsystem/src/requests.cpp
index 8538d9474..34a4d13c1 100644
--- a/posix/subsystem/src/requests.cpp
+++ b/posix/subsystem/src/requests.cpp
@@ -8,6 +8,7 @@
 #include <sys/timerfd.h>
 #include <sys/wait.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
 #include <helix/timer.hpp>
 
@@ -3483,6 +3484,55 @@ async::result<void> serveRequests(std::shared_ptr<Process> self,
 				helix_ng::sendBragiHeadOnly(resp, frg::stl_allocator{})
 			);
 			HEL_CHECK(sendResp.error());
+		}else if(preamble.id() == managarm::posix::SysconfRequest::message_id) {
+			auto req = bragi::parse_head_only<managarm::posix::SysconfRequest>(recv_head);
+
+			if (!req) {
+				std::cout << "posix: Rejecting request due to decoding failure" << std::endl;
+				break;
+			}
+
+			if(logRequests)
+				std::cout << "posix: SYSCONF" << std::endl;
+
+			managarm::posix::SysconfResponse resp;
+
+			// Configured == available == online
+			if(req->num() == _SC_NPROCESSORS_CONF || req->num() == _SC_NPROCESSORS_ONLN) {
+				managarm::kerncfg::GetNumCpuRequest kerncfgRequest;
+				auto [offer, kerncfgSendResp, kerncfgResp] = co_await helix_ng::exchangeMsgs(
+				getKerncfgLane(),
+				helix_ng::offer(
+						helix_ng::sendBragiHeadOnly(kerncfgRequest, frg::stl_allocator{}),
+						helix_ng::recvInline()
+					)
+				);
+				HEL_CHECK(offer.error());
+				HEL_CHECK(kerncfgSendResp.error());
+				HEL_CHECK(kerncfgResp.error());
+
+				auto kernResp = bragi::parse_head_only<managarm::kerncfg::GetNumCpuResponse>(kerncfgResp);
+
+				resp.set_error(managarm::posix::Errors::SUCCESS);
+				resp.set_value(kernResp->num_cpu());
+
+				auto [send_resp] = co_await helix_ng::exchangeMsgs(
+					conversation,
+					helix_ng::sendBragiHeadOnly(resp, frg::stl_allocator{})
+				);
+
+				HEL_CHECK(send_resp.error());
+			} else {
+				// Not handled, bubble up EINVAL.
+				resp.set_error(managarm::posix::Errors::ILLEGAL_ARGUMENTS);
+
+				auto [send_resp] = co_await helix_ng::exchangeMsgs(
+					conversation,
+					helix_ng::sendBragiHeadOnly(resp, frg::stl_allocator{})
+				);
+
+				HEL_CHECK(send_resp.error());
+			}
 		}else{
 			std::cout << "posix: Illegal request" << std::endl;
 			helix::SendBuffer send_resp;
diff --git a/protocols/posix/posix.bragi b/protocols/posix/posix.bragi
index cee33a2e3..5bb73f8b0 100644
--- a/protocols/posix/posix.bragi
+++ b/protocols/posix/posix.bragi
@@ -566,3 +566,14 @@ head(128):
 	uint64 available_memory;
 	uint64 memory_unit;
 }
+
+message SysconfRequest 93 {
+head(128):
+	int32 num;
+}
+
+message SysconfResponse 94 {
+head(128):
+	Errors error;
+	int64 value;
+}