why
build a system evolution
manual » script » makefile » auto-make » gn
- adv: quick, small, tree-structure(makefile has)
- disadv: it need all headers/libraries/source in side a package auto-make are created to use some uitiles to generate a makefile
reference: https://blog.simplypatrick.com/posts/2016/01-23-gn/
- 由於 GN 是用 C++ 撰寫，比起用 Python 寫的 GYP 快了將近 20 倍，GN 新的 DSL 的語法也被認為是比較好讀及維護的。
Usage
Use Steps
- configure some args
- Use gn to generate a build.ninja a inside ‘out’ folder
- Use ninja to read build.ninja and do its work!
>mkdir out
>copy gn.args to out
>gn gen out
>ninja -C out
download ninja
https://github.com/ninja-build/ninja/releases
tutorial (https://ninja-build.org/manual.html#ref_rule)[https://ninja-build.org/manual.html#ref_rule]
download gn
gn is a tool to help build chrome browse in windows it is a part of source code inside chrome use git’s sha1 hash-value to download the file
cheat sheet
gn ls out
; see all the taregets
gn check out
; check target dependences
gn desc out <target>
; descript the detail of target
gn refs out <target>
; list parent-targets that refs to target
gn path out <target1> <target2>
; show all paths from target1 to targets
tutorial https://chromium.googlesource.com/chromium/src/+/lkgr/tools/gn/docs/quick_start.md
gn download tool https://github.com/cpu-chromium/gn_tool
download code
with open(gn_path, 'wb') as f:
f.write(urllib2.urlopen('https://chromium-gn.storage-download.googleapis.com/' + sha1).read())
gn help
J:\git_home\temp\fluoride_src\fluoride\bt>gn help
Commands (type "gn help <command>" for more help):
analyze: Analyze which targets are affected by a list of files.
args: Display or configure arguments declared by the build.
check: Check header dependencies.
clean: Cleans the output directory.
desc: Show lots of insightful information about a target or config.
format: Format .gn file.
gen: Generate ninja files.
help: Does what you think.
ls: List matching targets.
path: Find paths between two targets.
refs: Find stuff referencing a target or file.
file format
gn use
- variables: use ‘=’ to assign
- rules: use a block (indent with spaces) to define
ninja_required_version = 1.3
#variable
cc = g++
cflags = -Wall
# rule
rule cc
command = gcc $cflags -c $in -o $out
rule link
command = gcc $cflags $in -o $out
build foo.o: cc foo.c
build
build .exe: link foo.c
another example by me
- use germ.c => germ.lib
- use foo.c => foo.o
- use foo.o + germ.lib => foo.exe
ninja_required_version = 1.3
#variable
cc = g++
cflags = -Wall
# rule
rule cc
command = gcc $cflags -c $in -o $out
rule ar
command = ar rcs $out $in
rule link
command = gcc $in -o $out -lgerm -L.
#build foo.o: cc foo.c
build germ.o: cc germ.c
build foo.o: cc foo.c
build germ.lib: ar germ.o
build foo.exe: link foo.o