Read Ruby source - 4. Prepare tools: global

Install "global" to read the source code.

Install

Refer this install page in Japanese, to install global on Mac.
http://qiita.com/5t111111/items/c14ac68f762ce71a7760

$ brew install global --with-exuberant-ctags --with-pygments
==> Downloading http://ftpmirror.gnu.org/global/global-6.5.tar.gz
==> Downloading from http://gd.tuwien.ac.at/gnu/gnusrc/global/global-6.5.tar.gz
######################################################################## 100.0%
==> Downloading https://pypi.python.org/packages/source/P/Pygments/Pygments-1.6.tar.gz
######################################################################## 100.0%
==> python setup.py build install --prefix=/usr/local/Cellar/global/6.5/libexec
==> ./configure --prefix=/usr/local/Cellar/global/6.5 --sysconfdir=/usr/local/etc --with-exu
==> make install

$ which global
/usr/local/bin/global

How to use

Create tag files.

Check config file.
You can see available file types for pygments parser too in this file.

$ view /usr/local/etc/gtags.conf
...
default:\
    :tc=native:
native:\
    :tc=gtags:tc=htags:
user:\
    :tc=user-custom:tc=htags:
ctags:\
    :tc=exuberant-ctags:tc=htags:
pygments:\
    :tc=pygments-parser:tc=htags:
...
#
# Plug-in parser to use Pygments.
#
pygments-parser|Pygments plug-in parser:\
...

Create tag files.
Create tags for C, C++, Ruby, and JavaScript, and etc files in Ruby source.
I took 5 minutes to finish this process.

$ cd $GIT_DIR/ruby
$ gtags --gtagslabel=pygments --debug

Tag files are created.

$ ls -rlt
...
-rw-r--r--    1 jun.aruga  staff  10289152 Dec 10 14:09 GTAGS
-rw-r--r--    1 jun.aruga  staff  21258240 Dec 10 14:09 GRTAGS
-rw-r--r--    1 jun.aruga  staff   1998848 Dec 10 14:09 GPATH

Search files with function in the directory.

Simply display files with main function, and .c file.

$ global main | grep '\.c$'
enc/mktable.c
ext/digest/md5/md5.c
ext/nkf/nkf-utf8/nkf.c
ext/openssl/ossl.c
main.c
missing/langinfo.c
strftime.c

With ctags format.

$ global -t main
...
main	main.c	23
...

With ctags cxref format.

$ global -x main
...
main               23 main.c           main(int argc, char **argv)
...

$ global -x parser_yylex
parser_yylex     13628 ext/ripper/ripper.c parser_yylex(struct parser_params *parser)
parser_yylex     13560 parse.c          parser_yylex(struct parser_params *parser)

Search files referring the function

Use -r option.

$ global -x -r parser_yylex
parser_yylex     14297 ext/ripper/ripper.c     t = parser_yylex(parser);
parser_yylex     14229 parse.c              t = parser_yylex(parser);

Funtastic!!

Jun's Blog

Output, activities, memo and etc.