Generate an installation script

This commit adds a `-g` flag to rcup(1) to generate a standalone shell
script. This shell script can then be run again, even on different
computers, to recreate the symlinks.

This allows people to recreate the "download my dotfiles and run
./install.sh" instructions, but with generated code that they do not
need to maintain.

This provides us more freedom with lsrc(1): since rcm can be used to
generate a universal shell script, lsrc(1) now can be harder to install
-- it can depend on a compiler, for example -- because you only need to
install it on one machine.

The generated script is rather limited; this can be improved in future
commits, as desired.

2 files changed, 76 insertions, 0 deletions

diff --git a/test/Makefile.am b/test/Makefile.am
index afa2631..aafa5ca 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -20,6 +20,7 @@ TESTS = \
 	rcrc.t \
 	rcup-link-files.t \
 	rcup-hostname.t \
+	rcup-standalone.t \
 	rcup-symlink-dirs.t \
 	rcup-usage.t
 
diff --git a/test/rcup-standalone.t b/test/rcup-standalone.t
new file mode 100644
index 0000000..7dd3b58
--- /dev/null
+++ b/test/rcup-standalone.t
@@ -0,0 +1,75 @@
+  $ . "$TESTDIR/helper.sh"
+
+-g generates a script
+
+  $ mkdir -p .dotfiles/eggplant_firetruck/lampshade
+  > touch .dotfiles/eggplant_firetruck/lampshade/bottle
+
+  $ rcup -g
+  #!/bin/sh
+  #
+  # Usage:
+  #
+  #    sh install.sh
+  #
+  # Environment variables: VERBOSE, CP, LN, MKDIR, RM, DIRNAME, XARGS.
+  #
+  #    env VERBOSE=1 sh install.sh
+  #
+  # DO NOT EDIT THIS FILE
+  # 
+  # This file is generated by rcm(7) as:
+  #
+  #   rcup -g
+  #
+  # To update it, re-run the above command.
+  #
+  : ${VERBOSE:=0}
+  : ${CP:=/bin/cp}
+  : ${LN:=/bin/ln}
+  : ${MKDIR:=/bin/mkdir}
+  : ${RM:=/bin/rm}
+  : ${DIRNAME:=/usr/bin/dirname}
+  : ${XARGS:=/usr/bin/xargs}
+  verbose() {
+    if [ "$VERBOSE" -gt 0 ]; then
+      echo "$@"
+    fi
+  }
+  handle_file_cp() {
+    if [ -e "$2" ]; then
+      printf "%s " "overwrite $2? [yN]"
+      read overwrite
+      case "$overwrite" in
+        y)
+          $RM -rf "$2"
+          ;;
+        *)
+          echo "skipping $2"
+          return
+          ;;
+      esac
+    fi
+    verbose "'$1' -> '$2'"
+    $DIRNAME "$2" | $XARGS $MKDIR -p
+    $CP -R "$1" "$2"
+  }
+  handle_file_ln() {
+    if [ -e "$2" ]; then
+      printf "%s " "overwrite $2? [yN]"
+      read overwrite
+      case "$overwrite" in
+        y)
+          $RM -rf "$2"
+          ;;
+        *)
+          echo "skipping $2"
+          return
+          ;;
+      esac
+    fi
+    verbose "'$1' -> '$2'"
+    $DIRNAME "$2" | $XARGS $MKDIR -p
+    $LN -sf "$1" "$2"
+  }
+  handle_file_ln "*eggplant_firetruck/lampshade/bottle" "*.eggplant_firetruck/lampshade/bottle" (glob)