firefox: use XShm 1.2 for screeen capture in webrtc, which works with

default pledges. With the help of robert@. ok landry@
2026-06-17 23:13:55 +02:00 · 2026-05-31 08:38:58 +00:00
parent 5d754a403c
commit f762b87f57
3 changed files with 131 additions and 13 deletions
@@ -10,6 +10,8 @@ MOZILLA_PROJECT =	firefox
 MOZILLA_CODENAME =	browser
 MOZILLA_PROFDATA_TASKID =	ZJmsHlaQS1eJnAogyhIejg

+REVISION =	0
+
 WRKDIST =	${WRKDIR}/${MOZILLA_DIST}-${MOZILLA_DIST_VERSION:C/b[0-9]*//}
 HOMEPAGE =	https://www.mozilla.org/firefox/
 SO_VERSION =	163.0
@@ -1,19 +1,108 @@
-https://bugzil.la/1702919, fallback to ximage
+Add XShm 1.2 support 

 Index: third_party/libwebrtc/modules/desktop_capture/linux/x11/x_server_pixel_buffer.cc
 --- third_party/libwebrtc/modules/desktop_capture/linux/x11/x_server_pixel_buffer.cc.orig
 +++ third_party/libwebrtc/modules/desktop_capture/linux/x11/x_server_pixel_buffer.cc
-@@ -212,7 +212,12 @@ bool XServerPixelBuffer::Init(XAtomCache* cache, Windo
- void XServerPixelBuffer::InitShm(const XWindowAttributes& attributes) {
-   Visual* default_visual = attributes.visual;
-   int default_depth = attributes.depth;
-
+@@ -17,6 +17,13 @@
+ #include <sys/ipc.h>
+ #include <sys/shm.h>
+ 
 +#if defined(__OpenBSD__)
-+// pledge(2)
-+  RTC_LOG(LS_WARNING) << "Unable to use shmget(2) while using pledge(2). "
-+                         "Performance may be degraded.";
-+  return;
+#include <X11/Xlib-xcb.h>
+#include <xcb/shm.h>
+#include <sys/mman.h>
+#include <unistd.h>
 +#endif
-   int major, minor;
-   Bool have_pixmaps;
-   if (!XShmQueryVersion(display_, &major, &minor, &have_pixmaps)) {
+
+ #include <cstdint>
+ #include <vector>
+ 
+@@ -170,13 +177,23 @@ void XServerPixelBuffer::ReleaseSharedMemorySegment() 
+   if (!shm_segment_info_)
+     return;
+   if (xshm_attached_) {
+#if defined(__OpenBSD__)
+    xcb_shm_detach(xcb_connection_, shm_segment_info_->shmseg);
+#else
+     XShmDetach(display_, shm_segment_info_);
+#endif
+     xshm_attached_ = false;
+   }
+   if (shm_segment_info_->shmaddr != nullptr)
+#if defined(__OpenBSD__)
+    munmap(shm_segment_info_->shmaddr, shm_size_);
+#else
+     shmdt(shm_segment_info_->shmaddr);
+#endif
+   if (shm_segment_info_->shmid != -1)
+#if !defined(__OpenBSD__)
+     shmctl(shm_segment_info_->shmid, IPC_RMID, nullptr);
+#endif
+   delete shm_segment_info_;
+   shm_segment_info_ = nullptr;
+ }
+@@ -224,21 +241,54 @@ void XServerPixelBuffer::InitShm(const XWindowAttribut
+   shm_segment_info_->shmid = -1;
+   shm_segment_info_->shmaddr = nullptr;
+   shm_segment_info_->readOnly = False;
+#if defined(__OpenBSD__)
+  shm_segment_info_->shmseg = XCB_NONE;
+#endif
+   x_shm_image_ = XShmCreateImage(display_, default_visual, default_depth,
+                                  ZPixmap, nullptr, shm_segment_info_,
+                                  window_rect_.width(), window_rect_.height());
+   if (x_shm_image_) {
+#if defined(__OpenBSD__)
+    char name[19] = "/webrtc-XXXXXXXXXX";
+    shm_size_ = x_shm_image_->bytes_per_line * x_shm_image_->height;
+    shm_segment_info_->shmid = shm_mkstemp(name);
+    shm_unlink(name);
+#else
+     shm_segment_info_->shmid =
+         shmget(IPC_PRIVATE, x_shm_image_->bytes_per_line * x_shm_image_->height,
+                IPC_CREAT | 0600);
+#endif
+     if (shm_segment_info_->shmid != -1) {
+#if defined(__OpenBSD__)
+      if (ftruncate(shm_segment_info_->shmid, shm_size_) < 0) {
+        close(shm_segment_info_->shmid);
+        return;
+      }
+      void* shmat_result = mmap(nullptr, shm_size_, PROT_READ | PROT_WRITE,
+				MAP_SHARED | __MAP_NOFAULT, shm_segment_info_->shmid, 0);
+      if (shmat_result == MAP_FAILED) {
+	close(shm_segment_info_->shmid);
+        return;
+      }
+#else
+       void* shmat_result = shmat(shm_segment_info_->shmid, nullptr, 0);
+#endif
+       if (shmat_result != reinterpret_cast<void*>(-1)) {
+         shm_segment_info_->shmaddr = reinterpret_cast<char*>(shmat_result);
+         x_shm_image_->data = shm_segment_info_->shmaddr;
+ 
+         XErrorTrap error_trap(display_);
+#if defined(__OpenBSD__)
+        xcb_connection_ = XGetXCBConnection(display_);
+        shm_segment_info_->shmseg = xcb_generate_id(xcb_connection_);
+        xcb_void_cookie_t cookie =
+	  xcb_shm_attach_fd_checked(xcb_connection_, shm_segment_info_->shmseg,
+				    shm_segment_info_->shmid, 0);
+        if (xcb_request_check(xcb_connection_, cookie) == NULL)
+          xshm_attached_ = true;
+#else
+         xshm_attached_ = XShmAttach(display_, shm_segment_info_);
+#endif
+         XSync(display_, False);
+         if (error_trap.GetLastErrorAndDisable() != 0)
+           xshm_attached_ = false;
+@@ -263,7 +313,9 @@ void XServerPixelBuffer::InitShm(const XWindowAttribut
+   if (have_pixmaps)
+     have_pixmaps = InitPixmaps(default_depth);
+ 
+#if !defined(__OpenBSD__)
+   shmctl(shm_segment_info_->shmid, IPC_RMID, nullptr);
+#endif
+   shm_segment_info_->shmid = -1;
+ 
+   RTC_LOG(LS_VERBOSE) << "Using X shared memory extension v" << major << "."
@@ -0,0 +1,27 @@
+XShm 1.2 support
+
+Index: third_party/libwebrtc/modules/desktop_capture/linux/x11/x_server_pixel_buffer.h
+--- third_party/libwebrtc/modules/desktop_capture/linux/x11/x_server_pixel_buffer.h.orig
+++ third_party/libwebrtc/modules/desktop_capture/linux/x11/x_server_pixel_buffer.h
+@@ -17,6 +17,10 @@
+ #include <X11/Xlib.h>
+ #include <X11/extensions/XShm.h>
+ 
+#if defined(__OpenBSD__)
+#include <xcb/xcb.h>
+#endif
+
+ #include <cstdint>
+ #include <vector>
+ 
+@@ -84,6 +88,10 @@ class XServerPixelBuffer {
+   bool xshm_attached_ = false;
+   bool xshm_get_image_succeeded_ = false;
+   std::vector<uint8_t> icc_profile_;
+#if defined(__OpenBSD__)
+  size_t shm_size_ = 0;
+  xcb_connection_t* xcb_connection_ = nullptr;
+#endif
+ };
+ 
+ }  // namespace webrtc