automatic, and accurate, make dependencies

...taking into account includes and behaviours
This code was originally committed as part of bug21673

3 files changed, 67 insertions, 9 deletions

diff --git a/.hgignore b/.hgignore
index fd096dda..442425f6 100644
--- a/.hgignore
+++ b/.hgignore
@@ -4,6 +4,7 @@ syntax: glob
 *.swp
 *.patch
 erl_crash.dump
+deps.mk
 
 syntax: regexp
 ^cover/
diff --git a/Makefile b/Makefile
index db8f7001..f75dd0ab 100644
--- a/Makefile
+++ b/Makefile
@@ -6,12 +6,14 @@ RABBITMQ_SERVER_START_ARGS ?=
 RABBITMQ_MNESIA_DIR ?= $(TMPDIR)/rabbitmq-$(RABBITMQ_NODENAME)-mnesia
 RABBITMQ_LOG_BASE ?= $(TMPDIR)
 
+DEPS_FILE=deps.mk
 SOURCE_DIR=src
 EBIN_DIR=ebin
 INCLUDE_DIR=include
-SOURCES=$(wildcard $(SOURCE_DIR)/*.erl)
-BEAM_TARGETS=$(EBIN_DIR)/rabbit_framing.beam $(patsubst $(SOURCE_DIR)/%.erl, $(EBIN_DIR)/%.beam, $(SOURCES))
-TARGETS=$(EBIN_DIR)/rabbit.app $(BEAM_TARGETS)
+INCLUDES=$(wildcard $(INCLUDE_DIR)/*.hrl) $(INCLUDE_DIR)/rabbit_framing.hrl
+SOURCES=$(wildcard $(SOURCE_DIR)/*.erl) $(SOURCE_DIR)/rabbit_framing.erl
+BEAM_TARGETS=$(patsubst $(SOURCE_DIR)/%.erl, $(EBIN_DIR)/%.beam, $(SOURCES))
+TARGETS=$(EBIN_DIR)/rabbit.app $(INCLUDE_DIR)/rabbit_framing.hrl $(BEAM_TARGETS)
 WEB_URL=http://stage.rabbitmq.com/
 MANPAGES=$(patsubst %.pod, %.gz, $(wildcard docs/*.[0-9].pod))
 
@@ -56,15 +58,15 @@ ERL_CALL=erl_call -sname $(RABBITMQ_NODENAME) -e
 
 ERL_EBIN=erl -noinput -pa $(EBIN_DIR)
 
-all: $(TARGETS)
+all: $(DEPS_FILE) $(TARGETS)
+
+$(DEPS_FILE): $(SOURCES) $(INCLUDES)
+	escript generate_deps $(INCLUDE_DIR) $(SOURCE_DIR) \$$\(EBIN_DIR\) $(DEPS_FILE)
 
 $(EBIN_DIR)/rabbit.app: $(EBIN_DIR)/rabbit_app.in $(BEAM_TARGETS) generate_app
 	escript generate_app $(EBIN_DIR) $@ < $<
 
-$(EBIN_DIR)/gen_server2.beam: $(SOURCE_DIR)/gen_server2.erl
-	erlc $(ERLC_OPTS) $<
-
-$(EBIN_DIR)/%.beam: $(SOURCE_DIR)/%.erl $(INCLUDE_DIR)/rabbit_framing.hrl $(INCLUDE_DIR)/rabbit.hrl $(EBIN_DIR)/gen_server2.beam
+$(EBIN_DIR)/%.beam: $(SOURCE_DIR)/%.erl
 	erlc $(ERLC_OPTS) -pa $(EBIN_DIR) $<
 #	ERLC_EMULATOR="erl -smp" erlc $(ERLC_OPTS) -pa $(EBIN_DIR) $<
 
@@ -100,6 +102,7 @@ clean:
 	rm -f $(INCLUDE_DIR)/rabbit_framing.hrl $(SOURCE_DIR)/rabbit_framing.erl codegen.pyc
 	rm -f docs/*.[0-9].gz
 	rm -f $(RABBIT_PLT)
+	rm -f $(DEPS_FILE)
 
 cleandb:
 	rm -rf $(RABBITMQ_MNESIA_DIR)/*
@@ -170,7 +173,7 @@ srcdist: distclean
 	sed -i.save 's/%%VSN%%/$(VERSION)/' $(TARGET_SRC_DIR)/ebin/rabbit_app.in && rm -f $(TARGET_SRC_DIR)/ebin/rabbit_app.in.save
 
 	cp -r $(AMQP_CODEGEN_DIR)/* $(TARGET_SRC_DIR)/codegen/
-	cp codegen.py Makefile generate_app calculate-relative $(TARGET_SRC_DIR)
+	cp codegen.py Makefile generate_app generate_deps calculate-relative $(TARGET_SRC_DIR)
 
 	cp -r scripts $(TARGET_SRC_DIR)
 	cp -r docs $(TARGET_SRC_DIR)
@@ -220,3 +223,5 @@ install: all docs_all install_dirs
 install_dirs:
 	mkdir -p $(SBIN_DIR)
 	mkdir -p $(TARGET_DIR)/sbin
+
+-include $(DEPS_FILE)
diff --git a/generate_deps b/generate_deps
new file mode 100644
index 00000000..916006d1
--- /dev/null
+++ b/generate_deps
@@ -0,0 +1,52 @@
+#!/usr/bin/env escript
+%% -*- erlang -*-
+-mode(compile).
+
+main([IncludeDir, ErlDir, EbinDir, TargetFile]) ->
+    ErlDirContents = filelib:wildcard("*.erl", ErlDir),
+    ErlFiles = [filename:join(ErlDir, FileName) || FileName <- ErlDirContents],
+    Modules = sets:from_list(
+                [list_to_atom(filename:basename(FileName, ".erl")) ||
+                    FileName <- ErlDirContents]),
+    Headers = sets:from_list(
+                [filename:join(IncludeDir, FileName) ||
+                    FileName <- filelib:wildcard("*.hrl", IncludeDir)]),
+    Deps = lists:foldl(
+             fun (Path, Deps1) ->
+                     dict:store(Path, detect_deps(IncludeDir, EbinDir,
+                                                  Modules, Headers, Path),
+                                Deps1)
+             end, dict:new(), ErlFiles),
+    {ok, Hdl} = file:open(TargetFile, [write, delayed_write]),
+    dict:fold(
+      fun (_Path, [], ok) ->
+              ok;
+          (Path, Dep, ok) ->
+              Module = filename:basename(Path, ".erl"),
+              ok = file:write(Hdl, [EbinDir, "/", Module, ".beam:"]),
+              ok = sets:fold(fun (E, ok) -> file:write(Hdl, [" ", E]) end,
+                             ok, Dep),
+              file:write(Hdl, [" ", ErlDir, "/", Module, ".erl\n"])
+      end, ok, Deps),
+    ok = file:write(Hdl, [TargetFile, ": ", escript:script_name(), "\n"]),
+    ok = file:sync(Hdl),
+    ok = file:close(Hdl).
+
+detect_deps(IncludeDir, EbinDir, Modules, Headers, Path) ->
+    {ok, Forms} = epp:parse_file(Path, [IncludeDir], [{use_specs, true}]),
+    lists:foldl(
+      fun ({attribute, _LineNumber, behaviour, Behaviour}, Deps) ->
+              case sets:is_element(Behaviour, Modules) of
+                  true  -> sets:add_element(
+                             [EbinDir, "/", atom_to_list(Behaviour), ".beam"],
+                             Deps);
+                  false -> Deps
+              end;
+          ({attribute, _LineNumber, file, {FileName, _LineNumber1}}, Deps) ->
+              case sets:is_element(FileName, Headers) of
+                  true  -> sets:add_element(FileName, Deps);
+                  false -> Deps
+              end;
+          (_Form, Deps) ->
+              Deps
+      end, sets:new(), Forms).