communicator/ssh: Allow custom generation of environment variable exports

plugins/communicators/ssh/communicator.rb

@@ -540,7 +540,7 @@ module VagrantPlugins
             end
 
             # Set the terminal
-            ch2.send_data "export TERM=vt100\n"
+            ch2.send_data generate_environment_export("TERM", "vt100")
 
             # Set SSH_AUTH_SOCK if we are in sudo and forwarding agent.
             # This is to work around often misconfigured boxes where
@@ -563,7 +563,7 @@ module VagrantPlugins
                 @logger.warn("No SSH_AUTH_SOCK found despite forward_agent being set.")
               else
                 @logger.info("Setting SSH_AUTH_SOCK remotely: #{auth_socket}")
-                ch2.send_data "export SSH_AUTH_SOCK=#{auth_socket}\n"
+                ch2.send_data generate_environment_export("SSH_AUTH_SOCK", auth_socket)
               end
             end
 
@@ -572,9 +572,9 @@ module VagrantPlugins
             # without the cruft added from pty mode.
             if pty
               data = "stty raw -echo\n"
-              data += "export PS1=\n"
-              data += "export PS2=\n"
-              data += "export PROMPT_COMMAND=\n"
+              data += generate_environment_export("PS1", "")
+              data += generate_environment_export("PS2", "")
+              data += generate_environment_export("PROMPT_COMMAND", "")
               data += "printf #{PTY_DELIM_START}\n"
               data += "#{command}\n"
               data += "exitcode=$?\n"
@@ -670,6 +670,11 @@ module VagrantPlugins
         source_path = Vagrant.source_root.join("keys", "vagrant")
         return File.read(path).chomp == source_path.read.chomp
       end
+
+      def generate_environment_export(env_key, env_value)
+        template = @machine.config.ssh.export_command_template
+        template.sub("%ENV_KEY%", env_key).sub("%ENV_VALUE%", env_value) + "\n"
+      end
     end
   end
 end

plugins/kernel_v2/config/ssh.rb

@@ -15,24 +15,25 @@ module VagrantPlugins
       attr_accessor :ssh_command
       attr_accessor :pty
       attr_accessor :sudo_command
+      attr_accessor :export_command_template
 
       attr_reader :default
 
       def initialize
         super
 
-        @forward_agent = UNSET_VALUE
-        @forward_x11   = UNSET_VALUE
-        @forward_env   = UNSET_VALUE
-        @guest_port    = UNSET_VALUE
-        @keep_alive    = UNSET_VALUE
-        @proxy_command = UNSET_VALUE
-        @ssh_command   = UNSET_VALUE
-        @pty           = UNSET_VALUE
-        @shell         = UNSET_VALUE
-        @sudo_command  = UNSET_VALUE
-
-        @default    = SSHConnectConfig.new
+        @forward_agent           = UNSET_VALUE
+        @forward_x11             = UNSET_VALUE
+        @forward_env             = UNSET_VALUE
+        @guest_port              = UNSET_VALUE
+        @keep_alive              = UNSET_VALUE
+        @proxy_command           = UNSET_VALUE
+        @ssh_command             = UNSET_VALUE
+        @pty                     = UNSET_VALUE
+        @shell                   = UNSET_VALUE
+        @sudo_command            = UNSET_VALUE
+        @export_command_template = UNSET_VALUE
+        @default                 = SSHConnectConfig.new
       end
 
       def merge(other)
@@ -55,6 +56,10 @@ module VagrantPlugins
         @pty        = false if @pty == UNSET_VALUE
         @shell      = "bash -l" if @shell == UNSET_VALUE
 
+        if @export_command_template == UNSET_VALUE
+          @export_command_template = 'export %ENV_KEY%="%ENV_VALUE%"'
+        end
+
         if @sudo_command == UNSET_VALUE
           @sudo_command = "sudo -E -H %c"
         end

test/unit/plugins/communicators/ssh/communicator_test.rb

@@ -5,6 +5,8 @@ require Vagrant.source_root.join("plugins/communicators/ssh/communicator")
 describe VagrantPlugins::CommunicatorSSH::Communicator do
   include_context "unit"
 
+  let(:export_command_template){ 'export %ENV_KEY%="%ENV_VALUE%"' }
+
   # SSH configuration information mock
   let(:ssh) do
     double("ssh",
@@ -15,6 +17,7 @@ describe VagrantPlugins::CommunicatorSSH::Communicator do
       pty: false,
       keep_alive: false,
       insert_key: false,
+      export_command_template: export_command_template,
       shell: 'bash -l'
     )
   end
@@ -509,4 +512,18 @@ describe VagrantPlugins::CommunicatorSSH::Communicator do
       end
     end
   end
+
+  describe ".generate_environment_export" do
+    it "should generate bourne shell compatible export" do
+      communicator.send(:generate_environment_export, "TEST", "value").should eq("export TEST=\"value\"\n")
+    end
+
+    context "with custom template defined" do
+      let(:export_command_template){ "setenv %ENV_KEY% %ENV_VALUE%" }
+
+      it "should generate custom export based on template" do
+        communicator.send(:generate_environment_export, "TEST", "value").should eq("setenv TEST value\n")
+      end
+    end
+  end
 end

website/source/docs/vagrantfile/ssh_settings.html.md

@@ -126,6 +126,17 @@ only affects the shell to use when executing commands internally in Vagrant.
 
 <hr>
 
+`config.ssh.export_command_template` - The template used to generate
+exported environment variables in the active session. This can be useful
+when using a Bourne incompatible shell like C shell. The template supports
+two variables which are replaced with the desired environment variable key and
+environment variable value: `%ENV_KEY%` and `%ENV_VALUE%`. The default template
+is:
+
+```ruby
+config.ssh.export_command_template = 'export %ENV_KEY%="%ENV_VALUE%"'
+```
+
 `config.ssh.sudo_command` - The command to use when executing a command
 with `sudo`. This defaults to `sudo -E -H %c`. The `%c` will be replaced by
 the command that is being executed.