From bdfcb324f780c90de199b908837875dfc9b2e439 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Wed, 2 Sep 2015 18:17:15 +0200 Subject: Add dependency tracking (makedep) This is a very large change of a central part of Erlang.mk. I will admit that I am not quite confident on that one. If you do have issues following this change, please open a ticket and I will look at it immediately. At this point, it works for me, but I wouldn't be surprised to hear about a few minor issues. This commit introduces a dependency file $(PROJECT).d which contains Makefile rules between Erlang source files and headers, behaviors and parse_transforms. This allows us to rebuild only the files that are needed. The $(PROJECT).d is generated automatically when missing, and when any of the files change. It is possible to hook before and after this generation, by defining a $(PROJECT).d:: rule. This allows users to generate Erlang files which are then compiled by Erlang.mk automatically (and to track their dependencies, of course). Here goes nothing... --- core/erlc.mk | 155 +++++++++++++++++++------- doc/src/guide/app.asciidoc | 267 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 380 insertions(+), 42 deletions(-) create mode 100644 doc/src/guide/app.asciidoc diff --git a/core/erlc.mk b/core/erlc.mk index 88895a2..80affca 100644 --- a/core/erlc.mk +++ b/core/erlc.mk @@ -24,6 +24,9 @@ app_verbose = $(app_verbose_$(V)) appsrc_verbose_0 = @echo " APP " $(PROJECT).app.src; appsrc_verbose = $(appsrc_verbose_$(V)) +makedep_verbose_0 = @echo " DEPEND" $(PROJECT).d; +makedep_verbose = $(makedep_verbose_$(V)) + erlc_verbose_0 = @echo " ERLC " $(filter-out $(patsubst %,%.erl,$(ERLC_EXCLUDE)),\ $(filter %.erl %.core,$(?F))); erlc_verbose = $(erlc_verbose_$(V)) @@ -40,9 +43,11 @@ mib_verbose = $(mib_verbose_$(V)) # Targets. ifeq ($(wildcard ebin/test),) -app:: app-build +app:: + $(verbose) $(MAKE) --no-print-directory app-build else -app:: clean app-build +app:: clean + $(verbose) $(MAKE) --no-print-directory app-build endif ifeq ($(wildcard src/$(PROJECT)_app.erl),) @@ -70,7 +75,7 @@ define app_file endef endif -app-build: erlc-include ebin/$(PROJECT).app +app-build: ebin/$(PROJECT).app $(eval GITDESCRIBE := $(shell git describe --dirty --abbrev=7 --tags --always --first-parent 2>/dev/null || true)) $(eval MODULES := $(patsubst %,'%',$(sort $(notdir $(basename $(shell find ebin -type f -name *.beam)))))) ifeq ($(wildcard src/$(PROJECT).app.src),) @@ -87,61 +92,127 @@ else > ebin/$(PROJECT).app endif -erlc-include: - - $(verbose) if [ -d ebin/ ]; then \ - find include/ src/ -type f -name \*.hrl -newer ebin -exec touch $(shell find src/ -type f -name "*.erl") \; 2>/dev/null || printf ''; \ - fi +# Source files. -define compile_erl - $(erlc_verbose) erlc -v $(if $(IS_DEP),$(filter-out -Werror,$(ERLC_OPTS)),$(ERLC_OPTS)) -o ebin/ \ - -pa ebin/ -I include/ $(filter-out $(ERLC_EXCLUDE_PATHS),\ - $(COMPILE_FIRST_PATHS) $(1)) -endef +ifneq ($(wildcard src/),) +ERL_FILES = $(sort $(call core_find,src/,*.erl)) +CORE_FILES = $(sort $(call core_find,src/,*.core)) -define compile_xyrl - $(xyrl_verbose) erlc -v -o ebin/ $(1) - $(xyrl_verbose) erlc $(ERLC_OPTS) -o ebin/ ebin/*.erl - $(verbose) rm ebin/*.erl -endef +# ASN.1 files. -define compile_asn1 - $(asn1_verbose) erlc -v -I include/ -o ebin/ $(1) - $(verbose) mv ebin/*.hrl include/ - $(verbose) mv ebin/*.asn1db include/ - $(verbose) rm ebin/*.erl -endef +ifneq ($(wildcard asn1/),) +ASN1_FILES = $(sort $(call core_find,asn1/,*.asn1)) +ERL_FILES += $(addprefix src/,$(patsubst %.asn1,%.erl,$(notdir $(ASN1_FILES)))) -define compile_mib - $(mib_verbose) erlc -v $(ERLC_MIB_OPTS) -o priv/mibs/ \ - -I priv/mibs/ $(COMPILE_MIB_FIRST_PATHS) $(1) - $(mib_verbose) erlc -o include/ -- priv/mibs/*.bin +define compile_asn1 + $(verbose) mkdir -p include/ + $(asn1_verbose) erlc -v -I include/ -o asn1/ +noobj $(1) + $(verbose) mv asn1/*.erl src/ + $(verbose) mv asn1/*.hrl include/ + $(verbose) mv asn1/*.asn1db include/ endef -ifneq ($(wildcard src/),) -ebin/$(PROJECT).app:: - $(verbose) mkdir -p ebin/ - -ifneq ($(wildcard asn1/),) -ebin/$(PROJECT).app:: $(sort $(call core_find,asn1/,*.asn1)) - $(verbose) mkdir -p include +$(PROJECT).d:: $(ASN1_FILES) $(if $(strip $?),$(call compile_asn1,$?)) endif +# SNMP MIB files. + ifneq ($(wildcard mibs/),) -ebin/$(PROJECT).app:: $(sort $(call core_find,mibs/,*.mib)) - $(verbose) mkdir -p priv/mibs/ include - $(if $(strip $?),$(call compile_mib,$?)) +MIB_FILES = $(sort $(call core_find,mibs/,*.mib)) + +$(PROJECT).d:: $(MIB_FILES) + $(verbose) mkdir -p include/ priv/mibs/ + $(mib_verbose) erlc -v $(ERLC_MIB_OPTS) -o priv/mibs/ -I priv/mibs/ $(COMPILE_MIB_FIRST_PATHS) $(MIB_FILES) + $(mib_verbose) erlc -o include/ -- priv/mibs/*.bin endif -ebin/$(PROJECT).app:: $(sort $(call core_find,src/,*.erl *.core)) +# Leex and Yecc files. + +XRL_FILES = $(sort $(call core_find,src/,*.xrl)) +XRL_ERL_FILES = $(addprefix src/,$(patsubst %.xrl,%.erl,$(notdir $(XRL_FILES)))) +ERL_FILES += $(XRL_ERL_FILES) + +YRL_FILES = $(sort $(call core_find,src/,*.yrl)) +YRL_ERL_FILES = $(addprefix src/,$(patsubst %.yrl,%.erl,$(notdir $(YRL_FILES)))) +ERL_FILES += $(YRL_ERL_FILES) + +$(PROJECT).d:: $(XRL_FILES) $(YRL_FILES) + $(if $(strip $?),$(xyrl_verbose) erlc -v -o src/ $?) + +# Erlang and Core Erlang files. + +define makedep.erl + ErlFiles = lists:usort(string:tokens("$(ERL_FILES)", " ")), + Modules = [{filename:basename(F, ".erl"), F} || F <- ErlFiles], + Add = fun (Dep, Acc) -> + case lists:keyfind(atom_to_list(Dep), 1, Modules) of + {_, DepFile} -> [DepFile|Acc]; + false -> Acc + end + end, + AddHd = fun (Dep, Acc) -> + case {Dep, lists:keymember(Dep, 2, Modules)} of + {"src/" ++ _, false} -> [Dep|Acc]; + {"include/" ++ _, false} -> [Dep|Acc]; + _ -> Acc + end + end, + CompileFirst = fun (Deps) -> + First0 = [case filename:extension(D) of + ".erl" -> filename:basename(D, ".erl"); + _ -> [] + end || D <- Deps], + case lists:usort(First0) of + [] -> []; + [[]] -> []; + First -> ["COMPILE_FIRST +=", [[" ", F] || F <- First], "\n"] + end + end, + Depend = [begin + case epp:parse_file(F, [{includes, ["include/"]}]) of + {ok, Forms} -> + Deps = lists:usort(lists:foldl(fun + ({attribute, _, behavior, Dep}, Acc) -> Add(Dep, Acc); + ({attribute, _, behaviour, Dep}, Acc) -> Add(Dep, Acc); + ({attribute, _, compile, {parse_transform, Dep}}, Acc) -> Add(Dep, Acc); + ({attribute, _, file, {Dep, _}}, Acc) -> AddHd(Dep, Acc); + (_, Acc) -> Acc + end, [], Forms)), + [F, ":", [[" ", D] || D <- Deps], "\n", CompileFirst(Deps)]; + {error, enoent} -> + [] + end + end || F <- ErlFiles], + ok = file:write_file("$(1)", Depend), + halt() +endef + +$(PROJECT).d:: $(ERL_FILES) $(call core_find,include/,*.hrl) + $(makedep_verbose) $(call erlang,$(call makedep.erl,$@)) + +-include $(PROJECT).d + +ebin/$(PROJECT).app:: $(PROJECT).d + $(verbose) mkdir -p ebin/ + +define compile_erl + $(erlc_verbose) erlc -v $(if $(IS_DEP),$(filter-out -Werror,$(ERLC_OPTS)),$(ERLC_OPTS)) -o ebin/ \ + -pa ebin/ -I include/ $(filter-out $(ERLC_EXCLUDE_PATHS),$(COMPILE_FIRST_PATHS) $(1)) +endef + +ebin/$(PROJECT).app:: $(ERL_FILES) $(CORE_FILES) $(if $(strip $?),$(call compile_erl,$?)) -ebin/$(PROJECT).app:: $(sort $(call core_find,src/,*.xrl *.yrl)) - $(if $(strip $?),$(call compile_xyrl,$?)) +$(sort $(ERL_FILES) $(CORE_FILES)): + @touch $@ endif clean:: clean-app clean-app: - $(gen_verbose) rm -rf ebin/ priv/mibs/ \ - $(addprefix include/,$(addsuffix .hrl,$(notdir $(basename $(call core_find,mibs/,*.mib))))) + $(gen_verbose) rm -rf $(PROJECT).d ebin/ priv/mibs/ $(XRL_ERL_FILES) $(YRL_ERL_FILES) \ + $(addprefix include/,$(patsubst %.mib,.hrl,$(notdir $(MIB_FILES)))) \ + $(addprefix include/,$(patsubst %.asn1,.hrl,$(notdir $(ASN1_FILES)))) \ + $(addprefix include/,$(patsubst %.asn1,.asn1db,$(notdir $(ASN1_FILES)))) \ + $(addprefix src/,$(patsubst %.erl,.asn1db,$(notdir $(ASN1_FILES)))) diff --git a/doc/src/guide/app.asciidoc b/doc/src/guide/app.asciidoc new file mode 100644 index 0000000..880221a --- /dev/null +++ b/doc/src/guide/app.asciidoc @@ -0,0 +1,267 @@ +== Building + +Erlang.mk can do a lot of things, but it is, first and +foremost, a build tool. In this chapter we will cover +the basics of building a project with Erlang.mk. + +For most of this chapter, we will assume that you are +using a project link:getting_started.asciidoc[generated by Erlang.mk]. + +=== How to build + +To build a project, all you have to do is type `make`: + +[source,bash] +$ make + +It will work regardless of your project: OTP applications, +library applications, NIFs, port drivers or even releases. +Erlang.mk also automatically downloads and compiles the +dependencies for your project. + +All this is possible thanks to a combination of configuration +and conventions. Most of the conventions come from Erlang/OTP +itself so any seasoned Erlang developers should feel right at +home. + +=== What to build + +Erlang.mk gives you control over three steps of the build +process, allowing you to do a partial build if needed. + +A build has three phases: first any dependency is fetched +and built, then the project itself is built and finally a +release may be generated when applicable. A release is only +generated for projects specifically configured to do so. + +Erlang.mk handles those three phases automatically when you +type `make`. But sometimes you just want to repeat one or +two of them. + +The commands detailed in this section are most useful after +you have a successful build as they allow you to quickly +redo a step instead of going through everything. This is +especially useful for large projects or projects that end +up generating releases. + +==== Application + +You can build your application specifically, without +looking at handling dependencies or generating a release, +by running the following command: + +[source,bash] +$ make app + +This command is very useful if you have a lot of dependencies +and develop on a machine with slow file access, like the +Raspberry Pi and many other embedded devices. + +Note that this command may fail if a required dependency +is missing. + +==== Dependencies + +You can build all dependencies, and nothing else, by +running the following command: + +[source,bash] +$ make deps + +This will fetch and compile all dependencies and their +dependencies, recursively. + +link:deps.asciidoc[Packages and dependencies] are covered +in the next chapter. + +==== Release + +You can generate the release, skipping the steps for building +the application and dependencies, by running the following +command: + +[source,bash] +$ make rel + +This command can be useful if nothing changed except the +release configuration files. + +Consult the link:relx.asciidoc[Releases] chapter for more +information about what releases are and how they are generated. + +Note that this command may fail if a required dependency +is missing. + +=== Application resource file + +When building your application, Erlang.mk will generate the +http://www.erlang.org/doc/man/app.html[application resource file]. +This file is mandatory for all Erlang applications and is +found in 'ebin/$(PROJECT).app'. + +`PROJECT` is a variable defined in your Makefile and taken +from the name of the directory when Erlang.mk bootstraps +your project. + +Erlang.mk can build the 'ebin/$(PROJECT).app' in two different +ways: from the configuration found in the Makefile, or from +the 'src/$(PROJECT).app.src' file. + +==== Application configuration + +Erlang.mk automatically fills the `PROJECT` variable when +bootstrapping a new project, but everything else is up to +you. None of the values are required to build your project, +although it is recommended to fill everything relevant to +your situation. + +`PROJECT`:: + The name of the OTP application or library. +`PROJECT_DESCRIPTION`:: + Short description of the project. +`PROJECT_VERSION`:: + Current version of the project. +`PROJECT_REGISTERED`:: + List of the names of all registered processes. +`OTP_DEPS`:: + List of Erlang/OTP applications this project depends on, + excluding `erts`, `kernel` and `stdlib`. +`DEPS`:: + List of applications this project depends on that need + to be fetched by Erlang.mk. + +There's no need for quotes or anything. The relevant part of +the Cowboy Makefile follows, if you need an example: + +[source,make] +---- +PROJECT = cowboy +PROJECT_DESCRIPTION = Small, fast, modular HTTP server. +PROJECT_VERSION = 2.0.0-pre.2 +PROJECT_REGISTERED = cowboy_clock + +OTP_DEPS = crypto +DEPS = cowlib ranch +---- + +Any space before and after the value is dropped. + +link:deps.asciidoc[Dependencies] are covered in details in +the next chapter. + +==== Legacy method + +The 'src/$(PROJECT).app.src' file is a legacy method of +building Erlang applications. It was introduced by the original +`rebar` build tool, of which Erlang.mk owes a great deal as it +is its main inspiration. + +The '.app.src' file serves as a template to generate the '.app' +file. Erlang.mk will take it, fill in the `modules` value +dynamically, and save the result in 'ebin/$(PROJECT).app'. + +When using this method, Erlang.mk cannot fill the `applications` +key from dependencies automatically, which means you need to +add them to Erlang.mk and to the '.app.src' at the same time, +duplicating the work. + +=== File formats + +Erlang.mk supports a variety of different source file formats. +The following formats are supported natively: + +[cols="<,3*^",options="header"] +|=== +| Extension | Location | Description | Output +| .erl | src/ | Erlang source | ebin/*.beam +| .core | src/ | Core Erlang source | ebin/*.beam +| .xrl | src/ | Leex source | src/*.erl +| .yrl | src/ | Yecc source | src/*.erl +| .asn1 | asn1/ | ASN.1 files | include/*.hrl include/*.asn1db src/*.erl +| .mib | mibs/ | SNMP MIB files | include/*.hrl priv/mibs/*.bin +|=== + +Files are always searched recursively. + +The build is ordered, so that files that generate Erlang source +files are run before, and the resulting Erlang source files are +then built normally. + +In addition, Erlang.mk keeps track of header files (`.hrl`) +as described at the end of this chapter. It can also compile +C code, as described in the link:ports.asciidoc[NIFs and port drivers] +chapter. + +Erlang.mk also comes with plugins for the following formats: + +[cols="<,3*^",options="header"] +|=== +| Extension | Location | Description | Output +| .dtl | templates/ | Django templates | ebin/*.beam +| .proto | src/ | Protocol buffers | ebin/*.beam +|=== + +=== Cold and hot builds + +The first time you run `make`, Erlang.mk will build everything. + +The second time you run `make`, and all subsequent times, Erlang.mk +will only rebuild what changed. Erlang.mk has been optimized for +this use case, as it is the most common during development. + +Erlang.mk figures out what changed by using the dependency tracking +feature of Make. Make automatically rebuilds a target if one of its +dependency has changed (for example if a header file has changed, +all the source files that include it will be rebuilt), and Erlang.mk +leverages this feature to cut down on rebuild times. + +Note that this applies only to building; some other features of +Erlang.mk will run every time they are called regardless of files +changed. + +=== Dependency tracking + +NOTE: This section is about the dependency tracking between files +inside your project, not application dependencies. + +Erlang.mk keeps track of the dependencies between the different +files in your project. This information is kept in the '$(PROJECT).d' +file in your directory. It is generated if missing, and will be +generated again after every file change, by default. + +Dependency tracking is what allows Erlang.mk to know when to +rebuild Erlang files when header files, behaviors or parse +transforms have changed. Erlang.mk also automatically keeps +track of which files should be compiled first, for example +when you have behaviors used by other modules in your project. + +=== Cleaning + +Building typically involves creating a lot of new files. Some +are reused in rebuilds, some are simply replaced. All can be +removed safely. + +Erlang.mk provides two commands to remove them: `clean` and +`distclean`. `clean` removes all the intermediate files that +were created as a result of building, including the BEAM files, +the dependency tracking file and the generated documentation. +`distclean` removes these and more, including the downloaded +dependencies, Dialyzer's PLT file and the generated release, +putting your directory back to the state it was before you +started working on it. + +To clean: + +[source,bash] +$ make clean + +Or distclean: + +[source,bash] +$ make distclean + +That is the question. + +Note that Erlang.mk will automatically clean some files as +part of other targets, but it will never run `distclean` if +you don't explicitly use it. -- cgit v1.2.3