credentials: add "cache" helper

If you access repositories over smart-http using http
authentication, then it can be annoying to have git ask you
for your password repeatedly. We cache credentials in
memory, of course, but git is composed of many small
programs. Having to input your password for each one can be
frustrating.

This patch introduces a credential helper that will cache
passwords in memory for a short period of time.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 77 insertions, 0 deletions

diff --git a/Documentation/git-credential-cache.txt b/Documentation/git-credential-cache.txt
new file mode 100644
index 0000000000..f3d09c5d51
--- /dev/null
+++ b/Documentation/git-credential-cache.txt
@@ -0,0 +1,77 @@
+git-credential-cache(1)
+=======================
+
+NAME
+----
+git-credential-cache - helper to temporarily store passwords in memory
+
+SYNOPSIS
+--------
+-----------------------------
+git config credential.helper 'cache [options]'
+-----------------------------
+
+DESCRIPTION
+-----------
+
+This command caches credentials in memory for use by future git
+programs. The stored credentials never touch the disk, and are forgotten
+after a configurable timeout.  The cache is accessible over a Unix
+domain socket, restricted to the current user by filesystem permissions.
+
+You probably don't want to invoke this command directly; it is meant to
+be used as a credential helper by other parts of git. See
+linkgit:gitcredentials[7] or `EXAMPLES` below.
+
+OPTIONS
+-------
+
+--timeout <seconds>::
+
+	Number of seconds to cache credentials (default: 900).
+
+--socket <path>::
+
+	Use `<path>` to contact a running cache daemon (or start a new
+	cache daemon if one is not started). Defaults to
+	`~/.git-credential-cache/socket`. If your home directory is on a
+	network-mounted filesystem, you may need to change this to a
+	local filesystem.
+
+CONTROLLING THE DAEMON
+----------------------
+
+If you would like the daemon to exit early, forgetting all cached
+credentials before their timeout, you can issue an `exit` action:
+
+--------------------------------------
+git credential-cache exit
+--------------------------------------
+
+EXAMPLES
+--------
+
+The point of this helper is to reduce the number of times you must type
+your username or password. For example:
+
+------------------------------------
+$ git config credential.helper cache
+$ git push http://example.com/repo.git
+Username: <type your username>
+Password: <type your password>
+
+[work for 5 more minutes]
+$ git push http://example.com/repo.git
+[your credentials are used automatically]
+------------------------------------
+
+You can provide options via the credential.helper configuration
+variable (this example drops the cache time to 5 minutes):
+
+-------------------------------------------------------
+$ git config credential.helper 'cache --timeout=300'
+-------------------------------------------------------
+
+GIT
+---
+Part of the linkgit:git[1] suite