sim: adapt macos avfoundation backend for camera indexing and capture

Adapt the macOS AVFoundation backend for multi-device discovery,
camera index mapping and capture startup compatibility. This enables
reliable use of multiple cameras through the SIM camera framework.

Signed-off-by: Peter Bee <bijunda@bytedance.com>

arch/sim/Kconfig

@@ -416,12 +416,17 @@ 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
 
+config SIM_CAMERA_AVFOUNDATION
+	bool "AVFoundation camera support on sim"
+	depends on HOST_MACOS
+
 endchoice
 
 config SIM_CAMERA_DEV_PATH

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>)