1# Copyright (C) 2022 The Android Open Source Project
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14#
15
16# Generate Rust bindings for C headers
17#
18# Bindgen reads C headers and generates compatible Rust declarations of types
19# and APIs. This allows us to keep Rust code in sync with C code that it depends
20# on.
21#
22# Input variables:
23# MODULE_BINDGEN_ALLOW_FILES
24# MODULE_BINDGEN_ALLOW_FUNCTIONS
25# MODULE_BINDGEN_ALLOW_TYPES
26# MODULE_BINDGEN_ALLOW_VARS
27# MODULE_BINDGEN_CTYPES_PREFIX
28# MODULE_BINDGEN_FLAGS
29# MODULE_BINDGEN_OUTPUT_ENV_VAR
30# MODULE_BINDGEN_SRC_HEADER
31# MODULE_BINDGEN_OUTPUT_FILE_NAME
32
33ifeq ($(strip $(MODULE_BINDGEN_SRC_HEADER)),)
34$(error $(MODULE): MODULE_BINDGEN_SRC_HEADER is required to use bindgen.mk)
35endif
36
37BINDGEN := $(CLANG_TOOLS_BINDIR)/bindgen
38
39ifeq ($(strip $(MODULE_BINDGEN_OUTPUT_FILE_NAME)),)
40MODULE_BINDGEN_OUTPUT_FILE := $(call TOBUILDDIR,$(patsubst %.h,%.rs,$(MODULE_BINDGEN_SRC_HEADER)))
41else
42MODULE_BINDGEN_OUTPUT_FILE := $(call TOBUILDDIR,$(dir $(MODULE_BINDGEN_SRC_HEADER))$(MODULE_BINDGEN_OUTPUT_FILE_NAME).rs)
43endif
44
45# Trusty rust is all no_std
46ifeq ($(MODULE_IS_KERNEL),true)
47MODULE_BINDGEN_FLAGS += --use-core --ctypes-prefix 'core::ffi'
48else
49MODULE_BINDGEN_FLAGS += --use-core --ctypes-prefix 'trusty_sys'
50endif
51
52ifneq ($(strip $(MODULE_BINDGEN_CTYPES_PREFIX)),)
53MODULE_BINDGEN_FLAGS += --ctypes-prefix $(MODULE_BINDGEN_CTYPES_PREFIX)
54endif
55
56MODULE_BINDGEN_FLAGS += $(addprefix --allowlist-var ,$(MODULE_BINDGEN_ALLOW_VARS))
57MODULE_BINDGEN_FLAGS += $(addprefix --allowlist-type ,$(MODULE_BINDGEN_ALLOW_TYPES))
58MODULE_BINDGEN_FLAGS += $(addprefix --allowlist-function ,$(MODULE_BINDGEN_ALLOW_FUNCTIONS))
59MODULE_BINDGEN_FLAGS += $(addprefix --allowlist-file ,$(MODULE_BINDGEN_ALLOW_FILES))
60# other sanitizer flags if present will cause bindgen to fail unless we pass
61# -fno-sanitize-ignorelist, see https://issues.chromium.org/issues/40265121
62BINDGEN_MODULE_COMPILEFLAGS := $(MODULE_COMPILEFLAGS) -fvisibility=default -fno-sanitize-ignorelist
63
64ifeq ($(call TOBOOL,$(TRUSTY_USERSPACE)),true)
65# library.mk overrides GLOBAL_COMPILEFLAGS and GLOBAL_INCLUDES for the .o, so we
66# must do the same here for bindgen
67$(MODULE_BINDGEN_OUTPUT_FILE): GLOBAL_COMPILEFLAGS := $(GLOBAL_SHARED_COMPILEFLAGS) $(GLOBAL_USER_COMPILEFLAGS) $(GLOBAL_USER_IN_TREE_COMPILEFLAGS) $(GLOBAL_USER_IN_TREE_CPPFLAGS)
68$(MODULE_BINDGEN_OUTPUT_FILE): GLOBAL_INCLUDES := $(addprefix -I,$(GLOBAL_UAPI_INCLUDES) $(GLOBAL_SHARED_INCLUDES) $(GLOBAL_USER_INCLUDES))
69endif
70
71-include $(MODULE_BINDGEN_OUTPUT_FILE).d
72
73MODULE_BINDGEN_DEFINES := $(MODULE_DEFINES)
74MODULE_BINDGEN_DEFINES += MODULE_BINDGEN_FLAGS=\"$(call clean_defines,$(MODULE_BINDGEN_FLAGS))\"
75MODULE_BINDGEN_DEFINES += BINDGEN_MODULE_COMPILEFLAGS=\"$(call clean_defines,$(BINDGEN_MODULE_COMPILEFLAGS))\"
76MODULE_BINDGEN_DEFINES += BINDGEN_MODULE_INCLUDES=\"$(call clean_defines,$(BINDGEN_MODULE_INCLUDES))\"
77
78MODULE_BINDGEN_CONFIG := $(call TOBUILDDIR,$(dir $(MODULE_BINDGEN_SRC_HEADER))/module_bindgen_config.h)
79$(MODULE_BINDGEN_CONFIG): MODULE_BINDGEN_DEFINES:=$(MODULE_BINDGEN_DEFINES)
80$(MODULE_BINDGEN_CONFIG): MODULE:=$(MODULE)
81$(MODULE_BINDGEN_CONFIG): configheader
82	@$(call INFO_DONE,$(MODULE),generating bindgen config header, $@)
83	@$(call MAKECONFIGHEADER,$@,MODULE_BINDGEN_DEFINES)
84
85$(MODULE_BINDGEN_OUTPUT_FILE): BINDGEN := $(BINDGEN)
86$(MODULE_BINDGEN_OUTPUT_FILE): BINDGEN_MODULE_COMPILEFLAGS := $(BINDGEN_MODULE_COMPILEFLAGS)
87$(MODULE_BINDGEN_OUTPUT_FILE): BINDGEN_MODULE_INCLUDES := $(addprefix -I,$(MODULE_INCLUDES))
88$(MODULE_BINDGEN_OUTPUT_FILE): ARCH_COMPILEFLAGS := $(ARCH_$(ARCH)_COMPILEFLAGS)
89$(MODULE_BINDGEN_OUTPUT_FILE): DEFINES := $(addprefix -D,$(MODULE_DEFINES))
90$(MODULE_BINDGEN_OUTPUT_FILE): MODULE_BINDGEN_FLAGS := $(MODULE_BINDGEN_FLAGS)
91$(MODULE_BINDGEN_OUTPUT_FILE): RUSTFMT_PATH := $(RUST_BINDIR)/rustfmt
92$(MODULE_BINDGEN_OUTPUT_FILE): $(MODULE_BINDGEN_SRC_HEADER) $(BINDGEN) $(MODULE_SRCDEPS) $(CONFIGHEADER) $(MODULE_BINDGEN_CONFIG)
93	@$(MKDIR)
94	$(NOECHO)
95	CLANG_PATH=$(BINDGEN_CLANG_PATH) \
96	LIBCLANG_PATH=$(BINDGEN_LIBCLANG_PATH) \
97	RUSTFMT=$(RUSTFMT_PATH) \
98	$(BINDGEN) $< -o $@.tmp $(MODULE_BINDGEN_FLAGS) --depfile $@.d -- $(GLOBAL_COMPILEFLAGS) $(ARCH_COMPILEFLAGS) $(BINDGEN_MODULE_COMPILEFLAGS) $(BINDGEN_MODULE_INCLUDES) $(GLOBAL_INCLUDES) $(DEFINES)
99	@$(call TESTANDREPLACEFILE,$@.tmp,$@)
100
101MODULE_SRCDEPS += $(MODULE_BINDGEN_OUTPUT_FILE)
102
103ifeq ($(MODULE_BINDGEN_OUTPUT_ENV_VAR),)
104MODULE_BINDGEN_OUTPUT_ENV_VAR := BINDGEN_INC_FILE
105endif
106
107# MODULE_BINDGEN_OUTPUT_ENV_VAR is not compatible with Soong as Soong does not allow
108# custom `envflags`. bindgen modules should resort to using `MODULE_BINDGEN_OUTPUT_FILE`
109# and `include!(concat!(env!("OUT_DIR"), "/{MODULE_BINDGEN_OUTPUT_FILE}"))` to include
110# the generated bindgen file.
111MODULE_RUST_ENV := $(MODULE_RUST_ENV) $(MODULE_BINDGEN_OUTPUT_ENV_VAR)=$(MODULE_BINDGEN_OUTPUT_FILE) OUT_DIR=$(dir $(MODULE_BINDGEN_OUTPUT_FILE))
112
113$(info $(MODULE_BINDGEN_OUTPUT_FILE))
114
115MODULE_BINDGEN_ALLOW_FILES :=
116MODULE_BINDGEN_ALLOW_FUNCTIONS :=
117MODULE_BINDGEN_ALLOW_TYPES :=
118MODULE_BINDGEN_ALLOW_VARS :=
119MODULE_BINDGEN_CONFIG :=
120MODULE_BINDGEN_CTYPES_PREFIX :=
121MODULE_BINDGEN_DEFINES :=
122MODULE_BINDGEN_OUTPUT_ENV_VAR :=
123MODULE_BINDGEN_OUTPUT_FILE_NAME :=
124MODULE_BINDGEN_SRC_HEADER :=
125
126BINDGEN :=
127MODULE_BINDGEN_FLAGS :=
128BINDGEN_MODULE_COMPILEFLAGS :=
129MODULE_BINDGEN_OUTPUT_FILE :=
130