Add gpg-agent plumbing for zsh

.zshrc

@@ -120,5 +120,9 @@ genpass() {
     openssl rand -base64 18
 }
 
+# Activate GPG agent and cache the password after first use
+# See: https://github.com/axtl/gpg-agent.zsh
+source ~/src/git/dotfiles/gpg-agent.plugin.zsh
+
 export PATH
 export MANPATH

gpg-agent.plugin.zsh

@@ -0,0 +1,58 @@
+local GPG_DIR="${HOME}/.gnupg"
+local GPG_ENV="${GPG_DIR}/gpg-agent.env"
+local SSH_SOCK=""
+local GPG_SOCK=""
+
+if [[ ! -z "${SSH_AUTH_SOCK}" ]]
+then
+    SSH_SOCK="${GPG_DIR}/$(basename ${SSH_AUTH_SOCK})"
+fi
+
+if [[ ! -z "${GPG_AGENT_INFO}" ]]
+then
+    GPG_SOCK="${GPG_DIR}/$(basename ${GPG_AGENT_INFO} | cut -d : -f1)"
+fi
+
+function _gpg_agent_start() {
+    emulate -L zsh
+    if [[ ! ( -f "${GPG_ENV}" && -S "${SSH_SOCK}" && -S "${GPG_SOCK}" ) ]]; then
+        _gpg_agent_clean
+        # start and source the script
+        eval "$(/usr/bin/env gpg-agent \
+                --quiet \
+                --daemon \
+                --enable-ssh-support \
+                --use-standard-socket \
+                --write-env-file ${GPG_ENV} \
+                2> /dev/null)"
+        chmod 600 "${GPG_ENV}"
+    fi
+
+    source "${GPG_ENV}" 2> /dev/null
+
+    export GPG_AGENT_INFO
+    export SSH_AUTH_SOCK
+    export SSH_AGENT_PID
+
+    GPG_TTY=$(tty)
+    export GPG_TTY
+}
+
+function _gpg_agent_reset() {
+    emulate -L zsh
+    _gpg_agent_clean
+    _gpg_agent_start 
+}
+
+function _gpg_agent_clean () {
+    emulate -L zsh
+    # clear possibly stale things
+    rm "${SSH_SOCK}" 2> /dev/null
+    rm "${GPG_SOCK}" 2> /dev/null
+    rm "${GPG_ENV}" 2> /dev/null
+    killall -9 gpg-agent 2> /dev/null
+    killall -9 ssh-agent 2> /dev/null
+}
+
+
+_gpg_agent_start