Merge branch 'mm/config-xdg'

Teach git to read various information from $XDG_CONFIG_HOME/git/ to allow
the user to avoid cluttering $HOME.

* mm/config-xdg:
  config: write to $XDG_CONFIG_HOME/git/config file when appropriate
  Let core.attributesfile default to $XDG_CONFIG_HOME/git/attributes
  Let core.excludesfile default to $XDG_CONFIG_HOME/git/ignore
  config: read (but not write) from $XDG_CONFIG_HOME/git/config file

4 files changed, 24 insertions, 7 deletions

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 0bcea8a..c6ff15e 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -484,7 +484,9 @@ core.excludesfile::
 	'.git/info/exclude', git looks into this file for patterns
 	of files which are not meant to be tracked.  "`~/`" is expanded
 	to the value of `$HOME` and "`~user/`" to the specified user's
-	home directory.  See linkgit:gitignore[5].
+	home directory. Its default value is $XDG_CONFIG_HOME/git/ignore.
+	If $XDG_CONFIG_HOME is either not set or empty, $HOME/.config/git/ignore
+	is used instead. See linkgit:gitignore[5].
 
 core.askpass::
 	Some commands (e.g. svn and http interfaces) that interactively
@@ -499,7 +501,9 @@ core.attributesfile::
 	In addition to '.gitattributes' (per-directory) and
 	'.git/info/attributes', git looks into this file for attributes
 	(see linkgit:gitattributes[5]). Path expansions are made the same
-	way as for `core.excludesfile`.
+	way as for `core.excludesfile`. Its default value is
+	$XDG_CONFIG_HOME/git/attributes. If $XDG_CONFIG_HOME is either not
+	set or empty, $HOME/.config/git/attributes is used instead.
 
 core.editor::
 	Commands such as `commit` and `tag` that lets you edit
diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt
index d9463cb..2d6ef32 100644
--- a/Documentation/git-config.txt
+++ b/Documentation/git-config.txt
@@ -97,10 +97,11 @@ OPTIONS
 
 --global::
 	For writing options: write to global ~/.gitconfig file rather than
-	the repository .git/config.
+	the repository .git/config, write to $XDG_CONFIG_HOME/git/config file
+	if this file exists and the ~/.gitconfig file doesn't.
 +
-For reading options: read only from global ~/.gitconfig rather than
-from all available files.
+For reading options: read only from global ~/.gitconfig and from
+$XDG_CONFIG_HOME/git/config rather than from all available files.
 +
 See also <<FILES>>.
 
@@ -194,7 +195,7 @@ See also <<FILES>>.
 FILES
 -----
 
-If not set explicitly with '--file', there are three files where
+If not set explicitly with '--file', there are four files where
 'git config' will search for configuration options:
 
 $GIT_DIR/config::
@@ -204,6 +205,14 @@ $GIT_DIR/config::
 	User-specific configuration file. Also called "global"
 	configuration file.
 
+$XDG_CONFIG_HOME/git/config::
+	Second user-specific configuration file. If $XDG_CONFIG_HOME is not set
+	or empty, $HOME/.config/git/config will be used. Any single-valued
+	variable set in this file will be overwritten by whatever is in
+	~/.gitconfig.  It is a good idea not to create this file if
+	you sometimes use older versions of Git, as support for this
+	file was added fairly recently.
+
 $(prefix)/etc/gitconfig::
 	System-wide configuration file.
 
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index 80120ea..e16f3e1 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -75,6 +75,8 @@ repositories (i.e., attributes of interest to all users) should go into
 `.gitattributes` files. Attributes that should affect all repositories
 for a single user should be placed in a file specified by the
 `core.attributesfile` configuration option (see linkgit:git-config[1]).
+Its default value is $XDG_CONFIG_HOME/git/attributes. If $XDG_CONFIG_HOME
+is either not set or empty, $HOME/.config/git/attributes is used instead.
 Attributes for all users on a system should be placed in the
 `$(prefix)/etc/gitattributes` file.
 
diff --git a/Documentation/gitignore.txt b/Documentation/gitignore.txt
index 2e7328b..c1f692a 100644
--- a/Documentation/gitignore.txt
+++ b/Documentation/gitignore.txt
@@ -50,7 +50,9 @@ the repository but are specific to one user's workflow) should go into
 the `$GIT_DIR/info/exclude` file.  Patterns which a user wants git to
 ignore in all situations (e.g., backup or temporary files generated by
 the user's editor of choice) generally go into a file specified by
-`core.excludesfile` in the user's `~/.gitconfig`.
+`core.excludesfile` in the user's `~/.gitconfig`. Its default value is
+$XDG_CONFIG_HOME/git/ignore. If $XDG_CONFIG_HOME is either not set or empty,
+$HOME/.config/git/ignore is used instead.
 
 The underlying git plumbing tools, such as
 'git ls-files' and 'git read-tree', read