sim/camera: add AVFoundation backend and multi-cam support

Documentation/applications/system/nxcamera/index.rst

@@ -1,3 +1,111 @@
-============================================
-``nxcamera`` NxCamera video test application
-============================================
+=============================================
+``nxcamera`` Camera/Video Stream Test Command
+=============================================
+
+Introduction
+============
+
+``nxcamera`` is a command-line utility for testing camera devices and video
+stream capture in NuttX. It is built on top of the NuttX video subsystem
+(using a V4L2-style interface) and is typically used to:
+
+- Enumerate and open video device nodes such as ``/dev/video0`` and
+  ``/dev/video1``
+- Configure capture parameters including resolution and pixel format
+- Capture video frames for validation, debugging, or simple data dumping,
+  depending on platform support and build configuration
+
+Usage
+=====
+
+``nxcamera`` is an interactive command-line program. Start it from NSH, then
+enter commands at the ``nxcamera>`` prompt:
+
+.. code-block:: console
+
+   nsh> nxcamera
+   nxcamera>
+
+Tip: Execute NSH Commands (Hidden)
+==================================
+
+At the ``nxcamera>`` prompt you can run an NSH command by prefixing it with
+``!``. This is useful for quickly checking system state or invoking other
+utilities without exiting ``nxcamera``.
+
+.. code-block:: console
+
+   nxcamera> !ls /dev
+   /dev:
+    console
+    fb0
+    gpio0
+    gpio1
+    gpio2
+    gpio3
+    loop
+    null
+    oneshot
+    ram0
+    ram1
+    ram2
+    video0
+    video1
+    zero
+   nxcamera> !poweroff
+   bash>
+
+A typical workflow at the prompt is:
+
+- ``input /dev/video0`` to set the input video node.
+- ``output /dev/fb0`` to set the output node, for example a framebuffer.
+- ``stream 640 480 30 NV12`` to start streaming with ``width height fps
+  format``.
+- ``stop`` to stop streaming.
+
+You may just copy-paste the commands below to get started:
+
+.. code-block:: console
+
+  nxcamera
+  input /dev/video0
+  output /dev/fb0
+  stream 640 480 30 YUYV # or NV12 on macOS
+
+Pixel Format
+============
+
+For the ``stream`` command, the pixel format depends on the platform. On the
+macOS ``sim`` platform you may use ``NV12``, while on Linux systems ``YUYV``
+is more commonly used.
+
+Examples
+========
+
+1. Start ``nxcamera`` and configure a typical interactive capture session:
+
+.. code-block:: console
+
+   nsh> nxcamera
+   nxcamera> input /dev/video0
+   nxcamera> output /dev/fb0
+   nxcamera> stream 640 480 30 NV12
+   nxcamera> stop
+
+.. figure:: nxcamera_macos_sim.png
+   :alt: nxcamera running on the macOS SIM platform
+   :align: center
+
+   ``nxcamera`` using the macOS AVFoundation backend on the SIM platform.
+
+Features and Updates
+====================
+
+- Multiple camera instances are supported, allowing several cameras to be
+  exposed as different device nodes such as ``/dev/video0`` and
+  ``/dev/video1``. This makes it easier to select and validate different
+  video input sources on the same system.
+- On the ``sim`` platform, support has been added for the macOS
+  AVFoundation backend. This enables camera capture and functional
+  verification on macOS hosts, subject to build configuration and host
+  permission settings.

arch/sim/Kconfig

@@ -406,20 +406,21 @@ if SIM_CAMERA
 
 choice
 	prompt "Simulated camera device type"
-	default SIM_CAMERA_V4L2
+	default SIM_CAMERA_V4L2 if HOST_LINUX
+	default SIM_CAMERA_AVFOUNDATION if HOST_MACOS
 
 config SIM_CAMERA_V4L2
 	bool "V4L2 camera support on sim"
 	depends on HOST_LINUX
 
-endchoice
+config SIM_CAMERA_AVFOUNDATION
+	bool "AVFoundation camera support on sim"
+	depends on HOST_MACOS
 
-config HOST_CAMERA_DEV_PATH
-	string "Host camera device path"
-	default "/dev/video0"
+endchoice
 
 config SIM_CAMERA_DEV_PATH
-	string "NuttX video device path"
+	string "NuttX video device path prefix"
 	default "/dev/video"
 
 endif

arch/sim/src/Makefile

@@ -110,11 +110,18 @@ CFLAGS += -fvisibility=default
 HOSTCFLAGS = $(ARCHWARNINGS) $(ARCHOPTIMIZATION) \
    $(ARCHCFLAGS) $(HOSTINCLUDES) $(EXTRAFLAGS) -D__SIM__ \
    -fvisibility=default
+HOSTMFLAGS = $(ARCHWARNINGS) $(ARCHOPTIMIZATION) \
+   $(ARCHCFLAGS) $(HOSTINCLUDES) $(EXTRAFLAGS) -D__SIM__ \
+   -fvisibility=default
 
 HOSTCFLAGS += ${INCDIR_PREFIX}$(ARCH_SRCDIR)
 HOSTCFLAGS += ${INCDIR_PREFIX}$(ARCH_SRCDIR)$(DELIM)chip
+
 ifeq ($(CONFIG_HOST_MACOS),y)
   HOSTCFLAGS += -Wno-deprecated-declarations
+ifeq ($(CONFIG_SIM_X11FB),y)
+  HOSTCFLAGS += -I/opt/X11/include
+endif
 endif
 
 ifeq ($(CONFIG_FS_LARGEFILE),y)
@@ -145,6 +152,11 @@ ifeq ($(CONFIG_HAVE_CXXINITIALIZE),y)
     LDFLAGS += -Wl,-ld_classic,-no_fixup_chains
   endif
 endif
+
+# Keep the simulator executable from exporting NuttX symbols. Otherwise dyld
+# may resolve host libc references against NuttX's internal libc implementation
+# during process initialization, which can crash before main() runs.
+LDFLAGS += -Wl,-exported_symbol,__mh_execute_header
 else
   STDLIBS += -lrt
 endif
@@ -313,6 +325,15 @@ ifeq ($(CONFIG_SIM_CAMERA_V4L2),y)
   STDLIBS += -lv4l2
 endif
 
+ifeq ($(CONFIG_SIM_CAMERA_AVFOUNDATION),y)
+  HOSTMSRCS += sim/macos/sim_host_avfoundation_backend.m
+  CSRCS += sim_camera.c
+ifeq ($(CONFIG_HOST_MACOS),y)
+  STDLIBS += -framework AVFoundation -framework CoreMedia \
+             -framework CoreVideo -framework Foundation
+endif
+endif
+
 ifeq ($(CONFIG_SIM_VIDEO_DECODER),y)
   CSRCS += sim_decoder.c
   CSRCS += sim_openh264dec.c
@@ -325,12 +346,14 @@ ifeq ($(CONFIG_SIM_VIDEO_ENCODER),y)
 endif
 
 COBJS = $(CSRCS:.c=$(OBJEXT))
+HOSTCOBJS = $(HOSTSRCS:.c=$(OBJEXT))
+HOSTMOBJS = $(HOSTMSRCS:.m=$(OBJEXT))
 
 NUTTXOBJS = $(AOBJS) $(COBJS)
-HOSTOBJS = $(HOSTSRCS:.c=$(OBJEXT))
+HOSTOBJS = $(HOSTCOBJS) $(HOSTMOBJS)
 HEADOBJ = $(HEADSRC:.c=$(OBJEXT))
 
-SRCS = $(ASRCS) $(CSRCS) $(HOSTSRCS)
+SRCS = $(ASRCS) $(CSRCS) $(HOSTSRCS) $(HOSTMSRCS)
 OBJS = $(AOBJS) $(COBJS) $(HOSTOBJS)
 
 $(foreach lib,$(notdir $(wildcard $(APPDIR)$(DELIM)staging$(DELIM)*$(LIBEXT))), \
@@ -386,11 +409,16 @@ $(AOBJS): %$(OBJEXT): %.S
 $(COBJS) $(LINKOBJS): %$(OBJEXT): %.c
 	$(call COMPILE, $<, $@)
 
-$(HOSTOBJS) $(HEADOBJ): %$(OBJEXT): %.c
+$(HOSTCOBJS) $(HEADOBJ): %$(OBJEXT): %.c
 	$(Q) $(ECHO_BEGIN)"CC:  $<"
 	$(Q) "$(CC)" -c $(HOSTCFLAGS) $< -o $@
 	$(Q) $(ECHO_END)
 
+$(HOSTMOBJS): %$(OBJEXT): %.m
+	$(Q) $(ECHO_BEGIN)"CC:  $<"
+	$(Q) $(HOSTCC) -c $(HOSTMFLAGS) -x objective-c $< -o $@
+	$(Q) $(ECHO_END)
+
 # The architecture-specific library
 
 libarch$(LIBEXT): $(NUTTXOBJS)
@@ -506,6 +534,9 @@ makedepfile: $(CSRCS:.c=.ddc) $(ASRCS:.S=.dds) $(HOSTSRCS:.c=.ddh)
 	$(call CATFILE, Make.dep, $^)
 	$(call DELFILE, $^)
 
+$(HOSTSRCS:.c=.ddh): %.ddh: %.c
+	$(Q) $(MKDEP) --obj-path $(OBJPATH) --obj-suffix $(OBJEXT) $(DEPPATH) "$(CC)" -- $(HOSTCFLAGS) -- $< > $@
+
 config.h: $(TOPDIR)/include/nuttx/config.h
 	@echo "CP:  $<"
 	$(Q) cp $< $@

arch/sim/src/sim/macos/CMakeLists.txt

@@ -0,0 +1,35 @@
+# ##############################################################################
+# arch/sim/src/sim/macos/CMakeLists.txt
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more contributor
+# license agreements.  See the NOTICE file distributed with this work for
+# additional information regarding copyright ownership.  The ASF licenses this
+# file to you under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License.  You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+# ##############################################################################
+
+add_library(sim_avf_backend OBJECT EXCLUDE_FROM_ALL
+                                   sim_host_avfoundation_backend.m)
+
+set_property(TARGET sim_avf_backend PROPERTY INCLUDE_DIRECTORIES "")
+set_property(TARGET sim_avf_backend PROPERTY COMPILE_OPTIONS "")
+set_property(TARGET sim_avf_backend PROPERTY COMPILE_DEFINITIONS "")
+set_property(TARGET sim_avf_backend PROPERTY INTERFACE_INCLUDE_DIRECTORIES "")
+set_property(TARGET sim_avf_backend PROPERTY INTERFACE_COMPILE_OPTIONS "")
+set_property(TARGET sim_avf_backend PROPERTY INTERFACE_COMPILE_DEFINITIONS "")
+
+target_include_directories(sim_avf_backend PRIVATE ${CMAKE_CURRENT_LIST_DIR})
+target_compile_options(sim_avf_backend
+                       PRIVATE $<$<COMPILE_LANGUAGE:OBJC>:-fobjc-arc>)