Add build with Docker, make and submodules

Starting to pull out hacks and custom instructions into a reproducible build.

.gitignore

@@ -1,5 +1,8 @@
 /.vscode/c_cpp_properties.json
-/.libs
 /libapi.*
 !/libapi.mjs.d.ts
 /node_modules
+/deps/*
+!/deps/libgphoto2
+!/deps/libusb
+/api.o

.gitmodules

@@ -0,0 +1,8 @@
+[submodule "libgphoto2"]
+	path = deps/libgphoto2
+	url = https://github.com/RReverser/libgphoto2
+	branch = em
+[submodule "libusb"]
+	path = deps/libusb
+	url = https://github.com/RReverser/libusb
+	branch = em

Dockerfile

@@ -0,0 +1,5 @@
+FROM emscripten/emsdk:2.0.26
+RUN apt-get update && apt-get install -qqy autoconf autopoint libtool-bin pkg-config
+WORKDIR /src
+ENV EM_CACHE /src/deps/.emcache
+CMD ["sh", "-c", "emmake make -j`nproc`"]

Makefile

@@ -1,9 +1,50 @@
-CPPFLAGS += -I $(GPHOTO2PREFIX)/include
+SYSROOT = $(PWD)/deps/.install
+export PKG_CONFIG_PATH = $(SYSROOT)/lib/pkgconfig
 
-libapi.mjs: api.cpp
-	libtool --verbose --mode=link --tag=CXX $(CC) -std=c++17 $+ --bind -s ASYNCIFY -fexceptions -Os -s ALLOW_MEMORY_GROWTH -s DYNAMIC_EXECUTION=0 -o $@ \
-	  $(GPHOTO2PREFIX)/lib/libltdl.la \
-	  $(GPHOTO2PREFIX)/lib/libgphoto2.la \
-	  -dlpreopen $(GPHOTO2PREFIX)/lib/libgphoto2/2.5.27.1/ptp2.la \
-	  -dlpreopen $(GPHOTO2PREFIX)/lib/libgphoto2_port/0.12.0/usb1.la \
-	  $(CPPFLAGS)
+export CPPFLAGS += -I$(SYSROOT)/include
+export LDFLAGS += -L$(SYSROOT)/lib -s DYNAMIC_EXECUTION=0 -s AUTO_JS_LIBRARIES=0 -s AUTO_NATIVE_LIBRARIES=0 -s ALLOW_UNIMPLEMENTED_SYSCALLS=0
+
+COMMON_FLAGS = -Os -flto
+export CFLAGS += $(COMMON_FLAGS)
+export CXXFLAGS += $(COMMON_FLAGS)
+export LDFLAGS += $(COMMON_FLAGS)
+
+libapi.mjs: api.o $(SYSROOT)/lib/libltdl.la $(SYSROOT)/lib/libgphoto2.la
+	deps/libgphoto2/libtool --verbose --mode=link $(LD) $(LDFLAGS) -o $@ $+ \
+		--bind -s ASYNCIFY -s ALLOW_MEMORY_GROWTH \
+		-dlpreopen $(SYSROOT)/lib/libgphoto2/2.5.27.1/ptp2.la \
+		-dlpreopen $(SYSROOT)/lib/libgphoto2_port/0.12.0/usb1.la
+
+api.o: deps/libgphoto2/configure.ac
+api.o: CPPFLAGS += -Ideps/libgphoto2 -Ideps/libgphoto2/libgphoto2_port
+api.o: CXXFLAGS += -std=c++17 -fexceptions
+
+$(SYSROOT)/.exists:
+	mkdir -p $(@D)
+	touch $@
+
+deps/libtool/configure:
+	mkdir -p deps/libtool
+	curl -L https://ftpmirror.gnu.org/libtool/libtool-2.4.6.tar.gz | tar zx --strip 1 -C deps/libtool
+
+deps/libgphoto2/configure.ac deps/libusb/configure.ac &:
+	git submodule update --init
+
+$(SYSROOT)/lib/libltdl.la: $(SYSROOT)/.exists deps/libtool/configure
+	cd deps/libtool && \
+	./configure --prefix=$(SYSROOT) --disable-shared && \
+	$(MAKE) install
+
+$(SYSROOT)/lib/libusb-1.0.la: $(SYSROOT)/.exists deps/libusb/configure.ac
+	cd deps/libusb && \
+	autoreconf -fiv && \
+	./configure --prefix=$(SYSROOT) --disable-shared --host=wasm32 && \
+	$(MAKE) install
+
+$(SYSROOT)/lib/libgphoto2.la: deps/libgphoto2/configure.ac $(SYSROOT)/lib/libltdl.la $(SYSROOT)/lib/libusb-1.0.la
+	cd deps/libgphoto2 && \
+	autoreconf -fiv && \
+	./configure --prefix=$(SYSROOT) --disable-shared --host=wasm32 \
+		 --without-libxml-2.0 --disable-nls --disable-ptpip --disable-disk \
+		 --with-camlibs=ptp2 && \
+	$(MAKE) install

build.sh

@@ -0,0 +1,6 @@
+#!/bin/sh
+docker build -t web-gphoto2 - < Dockerfile
+docker run --rm -it \
+	-v $PWD:/src \
+	-u $(id -u):$(id -g) \
+	web-gphoto2