[Fix #419] Rewrite module gpg-agent; rename it to gpg

modules/gpg/README.md

@@ -0,0 +1,16 @@
+GPG
+===
+
+Provides for an easier use of [GPG][1] by setting up [gpg-agent][2].
+
+Authors
+-------
+
+*The authors of this module should be contacted via the [issue tracker][3].*
+
+  - [Sorin Ionescu](https://github.com/sorin-ionescu)
+
+[1]: http://www.gnupg.org
+[2]: http://linux.die.net/man/1/gpg-agent
+[3]: https://github.com/sorin-ionescu/prezto/issues
+

modules/gpg/init.zsh

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+#
+# Provides for an easier use of GPG by setting up gpg-agent.
+#
+# Authors:
+#   Sorin Ionescu <sorin.ionescu@gmail.com>
+#
+
+# Return if requirements are not found.
+if (( ! $+commands[gpg-agent] )); then
+  return 1
+fi
+
+# Set the default path to the gpg-agent-info file.
+_gpg_agent_info="$HOME/.gpg-agent-info"
+
+# Start gpg-agent if not started.
+ps -U "$USER" -o ucomm | grep -q gpg-agent \
+  || gpg-agent --daemon >! "$_gpg_agent_info"
+
+# Export environment variables.
+export GPG_TTY="$(tty)"
+source "$_gpg_agent_info"
+
+# Clean up.
+unset _gpg_agent_info
+
+# Disable GUI prompts inside SSH.
+if [[ -n "$SSH_CONNECTION" ]]; then
+  export PINENTRY_USER_DATA='USE_CURSES=1'
+fi
+