1 files changed, 122 insertions, 0 deletions
diff --git a/link/lib.sh b/link/lib.sh
new file mode 100644
index 0000000..1899f00
--- /dev/null
+++ b/link/lib.sh
@@ -0,0 +1,122 @@
+# shellcheck shell=bash
+# shellcheck disable=SC2034  # the paths below are for whichever script sources this
+#
+# Shared by link.sh and the link/*.sh parts: the dry-run flag, colours, link and
+# link_all, and the paths they all use. Source it with the script's own
+# arguments:
+#
+#   source "$(dirname "$0")/lib.sh" "$@"
+#
+# Dry run unless the first argument is `yes`.
+#
+# Other repos' link.sh source this file instead of keeping copies, finding it
+# through $DOT_LINK_LIB, which link.sh exports for them. Keep these names and
+# the `yes` convention stable, or change them there as well.
+
+is_dry_run="y"
+if [[ "${1:-}" == "yes" ]]
+then
+  is_dry_run=""
+fi
+
+color() {
+  color_code="$1"
+  shift
+  # Black        0;30  Dark Gray     1;30
+  # Red          0;31  Light Red     1;31
+  # Green        0;32  Light Green   1;32
+  # Brown/Orange 0;33  Yellow        1;33
+  # Blue         0;34  Light Blue    1;34
+  # Purple       0;35  Light Purple  1;35
+  # Cyan         0;36  Light Cyan    1;36
+  # Light Gray   0;37  White         1;37
+  yes_color="\033[${color_code}m"
+  no_color='\033[0m'
+  echo -e "${yes_color}$*${no_color}"
+}
+
+green() {
+  color '0;32' "$@"
+}
+
+yellow() {
+  color '1;33' "$@"
+}
+
+red() {
+  color '0;31' "$@"
+}
+
+# Link up dotfiles
+link() {
+  local target="$1"
+  local link="$2"
+  if [[ -z "$1" ]]
+  then
+    >&2 echo "Error: need valid target"
+    return 1
+  fi
+  if [[ -z "$2" ]]
+  then
+    >&2 echo "Error: need valid link"
+    return 1
+  fi
+  target="$(realpath "${target}")"
+
+  if [[ -n "${is_dry_run}" ]]
+  then
+    local actual
+    actual="$(readlink "$link" || true)"
+    if [[ -n "${actual}" ]] ; then
+      actual="$(realpath "$actual" || true)"
+    fi
+
+    if [[ -L "$link" && "$target" == "$actual" ]]
+    then
+      green "$link already exists and is correct"
+      return
+    elif [[ -e "$link" ]]
+    then
+      if diff "$link" "$target" > /dev/null
+      then
+        yellow "$link already exists and will be deleted first but contents are the same. $target != $actual"
+      else
+        red "$link WILL CHANGE"
+      fi
+    else
+      yellow "$link will be created"
+    fi
+  else
+    mkdir -p "$(dirname "$2")"
+    rm -rf "$2"
+    ln -sf "$1" "$2"
+  fi
+}
+
+link_all() {
+  from="$1"
+  to="$2"
+  # Process substitution rather than a pipe, so `link` runs in this shell and
+  # not a subshell; NUL-delimited so names with spaces survive (SC2044/SC2086).
+  while IFS= read -r -d '' f
+  do
+    link "$f" "$to/$(basename "$f")"
+  done < <(find "$from" -mindepth 1 -maxdepth 1 -print0)
+}
+
+# Run another script with this interface, dry or not as this one is.
+run_link() {
+  if [[ -n "${is_dry_run}" ]]
+  then
+    "$1"
+  else
+    "$1" yes
+  fi
+}
+
+dotfiles_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+config_dir="$dotfiles_dir/config"
+xdg_config_dir="${XDG_CONFIG_HOME:-$HOME/.config}"
+
+# iCloud Drive, on a Mac signed into it; absent everywhere else.
+icloud_dir="$HOME/Library/Mobile Documents/com~apple~CloudDocs"