replace jq-generated sh by direct shv2.0.0

3 files changed, 236 insertions, 204 deletions

diff --git a/README b/README
index 6aeca5e..b1573aa 100644
--- a/README
+++ b/README
@@ -20,7 +20,6 @@ Next we'll run populate with a source specification:
       "mystuff": {
         "type": "file",
         "file": {
-          "exclude": [ ".git" "TODO*" ],
           "path": "/path/to/mystuff-1.0"
         }
       },
diff --git a/bin/populate b/bin/populate
index fdc4c5d..ab7dce5 100755
--- a/bin/populate
+++ b/bin/populate
@@ -1,75 +1,245 @@
 #! /bin/sh
 set -efu
 
-self=$(readlink -f "$0")
-basename=${0##*/}
-prefix=${self%/bin/*}
-libdir=$prefix/lib
+main() {(
+  self=$(readlink -f "$0")
+  basename=${0##*/}
 
-debug=false
-force=false
-origin_host=${HOSTNAME-cat /proc/sys/kernel/hostname}
-origin_user=$LOGNAME
-ssh_cmd=ssh
-target_spec=
+  debug=false
+  force=false
+  origin_host=${HOSTNAME-cat /proc/sys/kernel/hostname}
+  origin_user=$LOGNAME
+  target_spec=
 
 
-fail=true
+  fail=true
 
-error() {
-  echo "$basename: error: $1" >&2
-  fail=false
-}
+  error() {
+    echo "$basename: error: $1" >&2
+    fail=false
+  }
 
-for arg; do
-  case $arg in
-    --debug)
-      debug=true
-      ;;
-    --force)
-      force=true
-      ;;
-    --ssh=*)
-      ssh_cmd=${arg#--ssh=}
-      ;;
-    -*)
-      error "bad argument: $arg"
-      ;;
-    *)
-      if test -n "$target_spec"; then
+  for arg; do
+    case $arg in
+      --force)
+        force=true
+        ;;
+      -*)
         error "bad argument: $arg"
-      else
-        target_spec=$arg
-      fi
-      ;;
-  esac
-done
-
-if test -z "$target_spec"; then
-  error 'no target specified'
-fi
-
-if test "$fail" != true; then
-  exit 11
-fi
-
-
-script=$(jq -e -r \
-    --argjson use_force "$force" \
-    --arg ssh_cmd "$ssh_cmd" \
-    --arg target_spec "$target_spec" \
-    --arg origin_host "$origin_host" \
-    --arg origin_user "$origin_user" \
-    -f "$libdir/populate.jq")
-
-if test -z "$script"; then
-  error 'no script produced'
-  exit 12
-fi
-
-
-if test "$debug" = true; then
-  echo "$script"
-else
-  eval "$script"
-fi
+        ;;
+      *)
+        if test -n "$target_spec"; then
+          error "bad argument: $arg"
+        else
+          target_spec=$arg
+        fi
+        ;;
+    esac
+  done
+
+  if test -z "$target_spec"; then
+    error 'no target specified'
+  fi
+
+  if test "$fail" != true; then
+    exit 11
+  fi
+
+  target=$(
+    echo "$target_spec" | jq -R '
+      def default(value; f): if . == null then value else f end;
+      def default(value): default(value; .);
+
+      match("^(?:([^@]+)@)?([^:/]+)(?::([^/]*))?(/.*)?")
+      | {
+        user: .captures[0].string | default("root"),
+        host: .captures[1].string,
+        port: .captures[2].string | default(22;
+          if test("^[0-9]+$") then fromjson else
+            error(@json "bad target port: \(.)")
+          end),
+        path: .captures[3].string | default("/var/src"),
+      }
+    '
+  )
+
+  target_host=$(echo $target | jq -r .host)
+  target_path=$(echo $target | jq -r .path)
+  target_port=$(echo $target | jq -r .port)
+  target_user=$(echo $target | jq -r .user)
+
+  if test "$force" = true; then
+    force_target
+  else
+    check_target
+  fi
+
+  jq -c 'to_entries | group_by(.value.type) | flatten[]' |
+  while read -r source; do
+    key=$(echo "$source" | jq -r .key)
+    type=$(echo "$source" | jq -r .value.type)
+    case $type in
+      file)
+        file_path=$(echo "$source" | jq -r .value.file.path)
+        populate_file "$key" "$file_path"
+        ;;
+      git)
+        git_url=$(echo "$source" | jq -r .value.git.url)
+        git_ref=$(echo "$source" | jq -r .value.git.ref)
+        populate_git "$key" "$git_url" "$git_ref"
+        ;;
+      symlink)
+        symlink_target=$(echo "$source" | jq -r .value.symlink.target)
+        populate_symlink "$key" "$symlink_target"
+        ;;
+      *)
+        echo "Warning: ignoring $source" >&2
+        ;;
+    esac
+  done
+)}
+
+# Safeguard to prevent clobbering of misspelled targets.
+# This function has to be called first.
+check_target() {
+  {
+    echo target_host=$(quote "$target_host")
+    echo target_path=$(quote "$target_path")
+    echo 'sentinel_file=$target_path/.populate'
+    echo 'if ! test -f "$sentinel_file"; then'
+    echo '  echo "error: missing sentinel file: $target_host:$sentinel_file" >&2'
+    echo '  exit 1'
+    echo 'fi'
+  } \
+    |
+  target_shell
+}
+
+force_target() {
+  {
+    echo target_path=$(quote "$target_path")
+    echo 'sentinel_file=$target_path/.populate'
+    echo 'mkdir -vp "$target_path"'
+    echo 'touch "$sentinel_file"'
+  } \
+    |
+  target_shell
+}
+
+is_local_target() {
+  test "$target_host" = "$origin_host" &&
+  test "$target_user" = "$origin_user"
+}
+
+populate_file() {(
+  print_info populate_file "$@"
+
+  file_name=$1
+  file_path=$2
+
+  if is_local_target; then
+    file_target=$target_path/$file_name
+  else
+    file_target=$target_user@$target_host:$target_path/$file_name
+  fi
+
+  rsync \
+      -vFrlptD \
+      --delete-excluded \
+      "$file_path"/ \
+      -e "ssh -o ControlPersist=no -p $target_port" \
+      "$file_target"
+)}
+
+populate_git() {(
+  print_info populate_git "$@"
+
+  git_name=$1
+  git_url=$2
+  git_ref=$3
+
+  git_work_tree=$target_path/$git_name
+
+  {
+    echo set -efu
+
+    echo git_name=$(quote "$git_name")
+    echo git_url=$(quote "$git_url")
+    echo git_ref=$(quote "$git_ref")
+
+    echo git_work_tree=$(quote "$git_work_tree")
+
+    echo 'if ! test -e "$git_work_tree"; then'
+    echo '  git clone "$git_url" "$git_work_tree"'
+    echo 'fi'
+
+    echo 'cd $git_work_tree'
+
+    echo 'if ! url=$(git config remote.origin.url); then'
+    echo '  git remote add origin "$git_url"'
+    echo 'elif test "$url" != "$git_url"; then'
+    echo '  git remote set-url origin "$git_url"'
+    echo 'fi'
+
+    # TODO resolve git_ref to commit hash
+    echo 'hash=$git_ref'
+
+    echo 'if ! test "$(git log --format=%H -1)" = "$hash"; then'
+    echo '  if ! git log -1 "$hash" >/dev/null 2>&1; then'
+    echo '    git fetch origin'
+    echo '  fi'
+    echo '  git checkout "$hash" -- "$git_work_tree"'
+    echo '  git -c advice.detachedHead=false checkout -f "$hash"'
+    echo 'fi'
+
+    echo 'git clean -dfx'
+
+  } \
+    |
+  target_shell
+)}
+
+populate_symlink() {(
+  print_info populate_symlink "$@"
+
+  symlink_name=$1
+  symlink_source=$2
+
+  symlink_target=$target_path/$symlink_name
+
+  {
+    # TODO rm -fR instead of ln -f?
+    echo ln -fns $(quote "$symlink_source" "$symlink_target")
+  } \
+    |
+  target_shell
+)}
+
+print_info() {
+  printf '\e[1;33m* %s\e[m\n' "$*" >&2
+}
+
+quote() {
+  printf %s "$1" | sed 's/./\\&/g'
+  while test $# -gt 1; do
+    printf ' '
+    shift
+    printf %s "$1" | sed 's/./\\&/g'
+  done
+  echo
+}
+
+target_shell() {
+  if is_local_target; then
+    /bin/sh
+  else
+    ssh "$target_host" \
+        -l "$target_user" \
+        -o ControlPersist=no \
+        -p "$target_port" \
+        -T \
+        /bin/sh
+  fi
+}
+
+main "$@"
diff --git a/lib/populate.jq b/lib/populate.jq
deleted file mode 100644
index d7cf964..0000000
--- a/lib/populate.jq
+++ /dev/null
@@ -1,137 +0,0 @@
-def default(value; f): if . == null then value else f end;
-def default(value): default(value; .);
-
-($target_spec
-  | match("^(?:([^@]+)@)?([^:/]+)(?::([^/]*))?(/.*)?")
-  | {
-    user: .captures[0].string | default("root"),
-    host: .captures[1].string,
-    port: .captures[2].string | default(22;
-      if test("^[0-9]+$") then fromjson else
-        error(@json "bad target port: \(.)")
-      end),
-    path: .captures[3].string | default("/var/src"),
-  }
-)
-  as $target |
-
-(($target.host == $origin_host) and ($target.user == $origin_user))
-  as $is_local |
-
-
-to_entries |
-map(select(.value.type == "file")) as $file_sources |
-map(select(.value.type == "git")) as $git_sources |
-map(select(.value.type == "symlink")) as $symlink_sources |
-
-($file_sources + $symlink_sources) as $rsync_sources |
-
-
-# Safeguard to prevent clobbering of misspelled targets.
-# This script must run at target first.
-def checktarget_script:
-  @sh "if ! test -f \($target.path)/.populate; then",
-  @sh "  echo error: missing sentinel file: \($target.host):\($target.path)/.populate >&2",
-  @sh "  exit 1",
-  @sh "fi";
-
-
-def forcetarget_script:
-  @sh "mkdir -vp \($target.path)",
-  @sh "touch \($target.path)/.populate";
-
-
-def git_script:
-  @sh "fetch_git(){(",
-  #@sh "  export SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt",
-
-  @sh "  dst_dir=\($target.path)/$1",
-  @sh "  src_url=$2",
-  @sh "  src_ref=$3",
-
-  @sh "  if ! test -e \"$dst_dir\"; then",
-  @sh "    git clone \"$src_url\" \"$dst_dir\"",
-  @sh "  fi",
-
-  @sh "  cd \"$dst_dir\"",
-
-  @sh "  if ! url=$(git config remote.origin.url); then",
-  @sh "    git remote add origin \"$src_url\"",
-  @sh "  elif test \"$url\" != \"$src_url\"; then",
-  @sh "    git remote set-url origin \"$src_url\"",
-  @sh "  fi",
-
-  # TODO resolve src_ref to commit hash",
-  @sh "  hash=$src_ref",
-
-  @sh "  if ! test \"$(git log --format=%H -1)\" = \"$hash\"; then",
-  @sh "    if ! git log -1 \"$hash\" >/dev/null 2>&1; then",
-  @sh "      git fetch origin",
-  @sh "    fi",
-  @sh "    git checkout \"$hash\" -- \"$dst_dir\"",
-  @sh "    git checkout -f \"$hash\"",
-  @sh "  fi",
-
-  @sh "  git clean -dxf",
-  @sh ")}",
-  ($git_sources[] |
-  @sh "echo fetch_git \(.key) \(.value.git.url) \(.value.git.ref)",
-  @sh "fetch_git \(.key) \(.value.git.url) \(.value.git.ref)");
-
-
-def rsync_script:
-  @sh "srcdir=$(mktemp -dt populate.XXXXXXXX)",
-  @sh "chmod 0755 \"$srcdir\"",
-  @sh "trap cleanup EXIT",
-  @sh "cleanup() {",
-  @sh "  (set +f; rm -f \"$srcdir\"/*)",
-  @sh "  rmdir \"$srcdir\"",
-  @sh "}",
-
-  ($symlink_sources[] |
-  @sh "ln -s \(.value.symlink.target) \"$srcdir\"/\(.key)"),
-
-  @sh "proot \\",
-  ($file_sources[] |
-  @sh "    -b \(.value.file.path):\"$srcdir\"/\(.key) \\"),
-  @sh "    rsync \\",
-  @sh "        -vFrlptD \\",
-  @sh "        --delete-excluded \\",
-  @sh "        -f \("P /*", ($rsync_sources[] | "R /\(.key)")) \\",
-  ($file_sources[] | .key as $key | .value.file.exclude | select(. != null)[] |
-  @sh "        -f \("- /\($key)/\(.)") \\"),
-  @sh "        \"$srcdir\"/ \\",
-  (if $is_local then
-  @sh "        \($target.path)"
-  else
-  # ControlPersist=no so we reuse existing control sockets but if we
-  # create a new one, then remove it immediately after we are done so
-  # this script does not hang.
-  @sh "        -e \("\($ssh_cmd) -o ControlPersist=no -p \($target.port)") \\",
-  @sh "        \($target.user)@\($target.host):\($target.path)"
-  end);
-
-
-def compile:
-  [
-    @sh "set -euf",
-    .[]
-  ]
-  | map(select(. != null)) | join("\n");
-
-
-def ssh_target:
-  @sh "echo \(compile) \\",
-  @sh "  | \($ssh_cmd) \($target.user)@\($target.host) -p \($target.port) \\",
-  @sh "        -T \("nix-shell -p git --run /bin/sh")";
-
-
-[
-  (if $use_force then forcetarget_script else checktarget_script end),
-  git_script
-]
-| (if $is_local then . else [ssh_target] end),
-[
-  rsync_script
-]
-| compile