Switch from a rake-based build to a make-based build.

This commit beefs up the Makefile to do the build, instead of the
Rakefile.

It also removes from the Rakefile the dependency on rake_utils, which
should mean it's ok to build in a schroot.

The files are reorganised to make the Makefile rules more tractable,
although the reorganisation reveals a problem with our current code
organisation.

The problem is that the proxy-specific code transitively depends on the
server code via flexnbd.h, which has a circular dependency on the server
and client structs. This should be broken in a future commit by
separating the flexnbd struct into a shared config struct and
server-specific parts, so that the server code can be moved into
src/server to more accurately show the functional dependencies.

Makefile

@@ -1,10 +1,95 @@
 #!/usr/bin/make -f
 
-all:
-	rake build
+VPATH=src:tests/unit
+	
+ifdef DEBUG
+	CFLAGS_EXTRA=-g -DDEBUG
+	LDFLAGS_EXTRA=-g
+else
+	CFLAGS_EXTRA=-O2
+endif
+
+CCFLAGS=-D_GNU_SOURCE=1 -Wall -Wextra -Werror-implicit-function-declaration -Wstrict-prototypes -Wno-missing-field-initializers $(CFLAGS_EXTRA) $(CFLAGS)
+LLDFLAGS=-lrt -lev $(LDFLAGS_EXTRA) $(LDFLAGS)
+
+CC?=gcc
+
+LIBS=-lpthread
+INC=-I/usr/include/libev -Isrc/common -Isrc/server -Isrc/proxy
+COMPILE=$(CC) $(INC) -c $(CCFLAGS)
+SAVEDEP=$(CC) $(INC) -MM $(CCFLAGS)
+LINK=$(CC) $(LLDFLAGS) -Isrc $(LIBS)
+
+
+EXISTING_OBJS := $(wildcard build/*.o)
+-include $(EXISTING_OBJS:.o=.d)
+
+COMMON_SRC  := $(wildcard src/common/*.c)
+SERVER_SRC := $(wildcard src/server/*.c)
+PROXY_SRC   := $(wildcard src/proxy/*.c)
+
+COMMON_OBJ  := $(COMMON_SRC:src/%.c=build/%.o)
+SERVER_OBJ := $(SERVER_SRC:src/%.c=build/%.o)
+PROXY_OBJ   := $(PROXY_SRC:src/%.c=build/%.o)
+
+SRCS := $(COMMON_SRC) $(SERVER_SRC) $(PROXY_SRC)
+OBJS := $(COMMON_OBJ) $(SERVER_OBJ) $(PROXY_OBJ)
+
+
+build/%.o: %.c
+	mkdir -p $(dir $@)
+	$(COMPILE) $< -o $@
+	$(SAVEDEP) $< > build/$*.d
+
+objs: $(OBJS)
+
+build/flexnbd: $(COMMON_OBJ) $(SERVER_OBJ) build/main.o
+	$(LINK) $^ -o $@
+
+build/flexnbd-proxy: $(COMMON_OBJ) $(PROXY_OBJ) build/proxy-main.o
+	$(LINK) $^ -o $@
+
+server: build/flexnbd
+proxy: build/flexnbd-proxy
+all: build/flexnbd build/flexnbd-proxy
+
+
+CHECK_SRC := $(wildcard tests/unit/*.c)
+CHECK_OBJ := $(CHECK_SRC:tests/unit/%.c=build/tests/%.o)
+# Why can't we reuse the build/%.o rule above? Not sure.
+build/tests/%.o: tests/unit/%.c
+	mkdir -p $(dir $@)
+	$(COMPILE) $< -o $@
+	$(SAVEDEP) $< > build/tests/$*.d
+
+CHECK_BINS := $(CHECK_OBJ:build/tests/%.o=build/tests/%)
+build/tests/%: build/tests/%.o $(OBJS)
+	$(LINK) $^ -o $@ -lcheck
+
+check_objs: $(CHECK_OBJ)
+
+check_bins: $(CHECK_BINS)
+check: $(CHECK_BINS)
+	for bin in $^; do $$bin; done
+
+build/flexnbd.1: README.txt
+	a2x --destination-dir build --format manpage $<
+build/flexnbd-proxy.1: README.proxy.txt
+	a2x --destination-dir build --format manpage $<
+# If we don't pipe to file, gzip clobbers the original, causing make
+# to rebuild each time
+%.1.gz: %.1
+	gzip -c -f $< > $@
+
+
+server-man: build/flexnbd.1.gz
+proxy-man: build/flexnbd-proxy.1.gz
+
+doc: server-man proxy-man
 
-all-debug:
-	DEBUG=1 rake build
 
 clean:
-	rake clean
+	rm -rf build/*
+
+
+.PHONY: clean objs check_objs all server proxy check_bins check server-man proxy-man doc