From d787afb7e33e60fc2c6c0602f07ca0f27a2a1c0b Mon Sep 17 00:00:00 2001
From: Oskari Alaranta <oskari.alaranta@bananymous.com>
Date: Sat, 30 May 2026 17:52:09 +0300
Subject: [PATCH] Disable shared pixmaps on MIT-SHM

Our internal pixmap representation does not match what we advertice in
out pixmap formats, and there is no way to only enable 24 and 32 depth
pixmaps for SHM so just disable them all together. MIT-SHM can still be
used through Shm{Get,Put}Image. We probably should store pixmaps as we
say we do, but its too much work for now :^)
---
 xbanan/Base.cpp      |  3 +-
 xbanan/Definitions.h |  3 +-
 xbanan/ExtSHM.cpp    | 65 +-------------------------------------------
 3 files changed, 3 insertions(+), 68 deletions(-)

diff --git a/xbanan/Base.cpp b/xbanan/Base.cpp
index b867f20..fbd19d0 100644
--- a/xbanan/Base.cpp
+++ b/xbanan/Base.cpp
@@ -2052,8 +2052,7 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 						.depth = request.depth,
 						.width = request.width,
 						.height = request.height,
-						.data = data.span(),
-						.owned_data = BAN::move(data),
+						.data = BAN::move(data),
 					}
 				}))
 			));
diff --git a/xbanan/Definitions.h b/xbanan/Definitions.h
index 6af8b3a..bb7de9f 100644
--- a/xbanan/Definitions.h
+++ b/xbanan/Definitions.h
@@ -81,8 +81,7 @@ struct Object
 		CARD8 depth;
 		CARD32 width;
 		CARD32 height;
-		BAN::ByteSpan data;
-		BAN::Vector<uint8_t> owned_data;
+		BAN::Vector<uint8_t> data;
 	};
 
 	struct GraphicsContext
diff --git a/xbanan/ExtSHM.cpp b/xbanan/ExtSHM.cpp
index 721d2a0..01e3253 100644
--- a/xbanan/ExtSHM.cpp
+++ b/xbanan/ExtSHM.cpp
@@ -7,42 +7,13 @@
 #include <X11/X.h>
 #include <X11/extensions/shmproto.h>
 
-#include <netinet/in.h>
 #include <sys/shm.h>
-#include <sys/socket.h>
 #include <unistd.h>
 
 static BYTE s_shm_event_base;
 static BYTE s_shm_error_base;
 static BYTE s_shm_major_opcode;
 
-static bool is_local_socket(int socket)
-{
-	sockaddr_storage addr;
-	socklen_t addr_len = sizeof(addr);
-	if (getpeername(socket, reinterpret_cast<sockaddr*>(&addr), &addr_len) == -1)
-		return false;
-
-	switch (addr.ss_family)
-	{
-		case AF_UNIX:
-			return true;
-		case AF_INET:
-		{
-			const auto* addr_in = reinterpret_cast<const sockaddr_in*>(&addr);
-			const auto ipv4 = ntohl(addr_in->sin_addr.s_addr);
-			return (ipv4 & IN_CLASSA_NET) == IN_LOOPBACKNET;
-		}
-		case AF_INET6:
-		{
-			const auto* addr_in6 = reinterpret_cast<const sockaddr_in6*>(&addr);
-			return IN6_IS_ADDR_LOOPBACK(&addr_in6->sin6_addr);
-		}
-	}
-
-	return false;
-}
-
 static BAN::ErrorOr<void*> get_shmseg(Client& client_info, CARD32 shmseg, BYTE op_major, BYTE op_minor)
 {
 	auto it = g_objects.find(shmseg);
@@ -78,7 +49,7 @@ static BAN::ErrorOr<void> extension_shm(Client& client_info, BAN::ConstByteSpan
 
 			xShmQueryVersionReply reply {
 				.type = X_Reply,
-				.sharedPixmaps = is_local_socket(client_info.fd),
+				.sharedPixmaps = false,
 				.sequenceNumber = client_info.sequence,
 				.length = 0,
 				.majorVersion = 1,
@@ -265,40 +236,6 @@ static BAN::ErrorOr<void> extension_shm(Client& client_info, BAN::ConstByteSpan
 
 			break;
 		}
-		case X_ShmCreatePixmap:
-		{
-			auto request = decode<xShmCreatePixmapReq>(packet).value();
-
-			dprintln("ShmCreatePixmap");
-			dprintln("  depth:    {}", request.depth);
-			dprintln("  pid:      {}", request.pid);
-			dprintln("  drawable: {}", request.drawable);
-			dprintln("  width:    {}", request.width);
-			dprintln("  height:   {}", request.height);
-			dprintln("  shmseg:   {}", request.shmseg);
-			dprintln("  offset:   {}", request.offset);
-
-			ASSERT(request.depth == 24 || request.depth == 32);
-
-			void* shm_segment = TRY(get_shmseg(client_info, request.shmseg, op_major, op_minor));
-
-			TRY(client_info.objects.insert(request.pid));
-			TRY(g_objects.insert(
-				request.pid,
-				TRY(BAN::UniqPtr<Object>::create(Object {
-					.type = Object::Type::Pixmap,
-					.object = Object::Pixmap {
-						.depth = request.depth,
-						.width = request.width,
-						.height = request.height,
-						.data = BAN::ByteSpan(static_cast<uint8_t*>(shm_segment) + request.offset, request.width * request.height * 4),
-						.owned_data = {},
-					}
-				}))
-			));
-
-			break;
-		}
 		default:
 			dwarnln("unsupported shm minor opcode {}", packet[1]);
 			break;