pyenv verification source

libexec/pyenv-rehash

@@ -0,0 +1,201 @@
+#!/usr/bin/env bash
+# Summary: Rehash pyenv shims (run this after installing executables)
+
+set -e
+[ -n "$PYENV_DEBUG" ] && set -x
+
+SHIM_PATH="${PYENV_ROOT}/shims"
+PROTOTYPE_SHIM_PATH="${SHIM_PATH}/.pyenv-shim"
+
+# Create the shims directory if it doesn't already exist.
+mkdir -p "$SHIM_PATH"
+
+declare last_acquire_error
+
+acquire_lock() {
+  # Ensure only one instance of pyenv-rehash is running at a time by
+  # setting the shell's `noclobber` option and attempting to write to
+  # the prototype shim file. If the file already exists, print a warning
+  # to stderr and exit with a non-zero status.
+  local ret
+  set -o noclobber
+  last_acquire_error="$( { ( echo -n > "$PROTOTYPE_SHIM_PATH"; ) 2>&1 1>&3 3>&1-; } 3>&1)" || ret=1
+  set +o noclobber
+  [ -z "${ret}" ]
+}
+
+remove_prototype_shim() {
+  rm -f "$PROTOTYPE_SHIM_PATH"
+}
+
+release_lock() {
+  remove_prototype_shim
+}
+
+if [ ! -w "$SHIM_PATH" ]; then
+  echo "pyenv: cannot rehash: $SHIM_PATH isn't writable" >&2
+  exit 1
+fi
+
+declare acquired tested_for_other_write_errors
+declare start=$SECONDS
+PYENV_REHASH_TIMEOUT=${PYENV_REHASH_TIMEOUT:-60}
+while (( SECONDS <= start + PYENV_REHASH_TIMEOUT )); do
+  if acquire_lock; then
+    acquired=1
+
+    # If we were able to obtain a lock, register a trap to clean up the
+    # prototype shim when the process exits.
+    trap release_lock EXIT
+
+    break
+  else
+    #Landlock sandbox subsystem in the Linux kernel returns false information in access() as of 6.14.0,
+    # making -w "$SHIM_PATH" not catch the fact that the shims dir is not writable in this case.
+    #Bash doesn't provide access to errno to check for non-EEXIST error code in acquire_lock.
+    #So check for writablity by trying to write to a different file,
+    # in a way that taxes the usual use case as little as possible.
+    if [[ -z $tested_for_other_write_errors ]]; then
+      ( t="$(TMPDIR="$SHIM_PATH" mktemp)" && rm "$t" ) && tested_for_other_write_errors=1 ||
+        { echo "pyenv: cannot rehash: $SHIM_PATH isn't writable" >&2; break; }
+    fi
+    # POSIX sleep(1) doesn't provide subsecond precision, but many others do
+    sleep 0.1 2>/dev/null || sleep 1
+  fi
+done
+
+if [ -z "${acquired}" ]; then
+  if [[ -n $tested_for_other_write_errors ]]; then
+      echo "pyenv: cannot rehash: couldn't acquire lock"\
+        "$PROTOTYPE_SHIM_PATH for $PYENV_REHASH_TIMEOUT seconds. Last error message:" >&2
+      echo "$last_acquire_error" >&2
+  fi
+  exit 1
+fi
+unset tested_for_other_write_errors
+
+# The prototype shim file is a script that re-execs itself, passing
+# its filename and any arguments to `pyenv exec`. This file is
+# hard-linked for every executable and then removed. The linking
+# technique is fast, uses less disk space than unique files, and also
+# serves as a locking mechanism.
+create_prototype_shim() {
+  cat > "$PROTOTYPE_SHIM_PATH" <<SH
+#!/usr/bin/env bash
+set -e
+[ -n "\$PYENV_DEBUG" ] && set -x
+
+program="\${0##*/}"
+
+export PYENV_ROOT="$PYENV_ROOT"
+SHIM_PATH=\${0%/*}
+if [[ \$SHIM_PATH != "$PYENV_ROOT/shims" ]]; then
+  export _PYENV_SHIM_PATH="\$SHIM_PATH"
+fi
+exec "$(command -v pyenv)" exec "\$program" "\$@"
+SH
+  chmod +x "$PROTOTYPE_SHIM_PATH"
+}
+
+# If the contents of the prototype shim file differ from the contents
+# of the first shim in the shims directory, assume pyenv has been
+# upgraded and the existing shims need to be removed.
+remove_outdated_shims() {
+  local shim
+  for shim in "$SHIM_PATH"/*; do
+    if ! diff "$PROTOTYPE_SHIM_PATH" "$shim" >/dev/null 2>&1; then
+      rm -f "$SHIM_PATH"/*
+    fi
+    break
+  done
+}
+
+# The basename of each argument passed to `make_shims` will be
+# registered for installation as a shim. In this way, plugins may call
+# `make_shims` with a glob to register many shims at once.
+make_shims() {
+  local file shim
+  for file; do
+    shim="${file##*/}"
+    register_shim "$shim"
+  done
+}
+
+if ((${BASH_VERSINFO[0]} > 3)); then
+
+  declare -A registered_shims
+
+  # Registers the name of a shim to be generated.
+  register_shim() {
+    registered_shims["$1"]=1
+  }
+
+  # Install all shims registered via `make_shims` or `register_shim` directly.
+  install_registered_shims() {
+    local shim file
+    for shim in "${!registered_shims[@]}"; do
+      file="${SHIM_PATH}/${shim}"
+      [ -e "$file" ] || cp "$PROTOTYPE_SHIM_PATH" "$file"
+    done
+  }
+
+  # Once the registered shims have been installed, we make a second pass
+  # over the contents of the shims directory. Any file that is present
+  # in the directory but has not been registered as a shim should be
+  # removed.
+  remove_stale_shims() {
+    local shim
+    for shim in "$SHIM_PATH"/*; do
+      if [[ ! ${registered_shims["${shim##*/}"]} ]]; then
+        rm -f "$shim"
+      fi
+    done
+  }
+
+else # Same for bash < 4.
+
+    registered_shims=" "
+
+    register_shim() {
+      registered_shims="${registered_shims}${1} "
+    }
+
+    install_registered_shims() {
+      local shim file
+      for shim in $registered_shims; do
+        file="${SHIM_PATH}/${shim}"
+        [ -e "$file" ] || cp "$PROTOTYPE_SHIM_PATH" "$file"
+      done
+    }
+
+    remove_stale_shims() {
+      local shim
+      for shim in "$SHIM_PATH"/*; do
+        if [[ "$registered_shims" != *" ${shim##*/} "* ]]; then
+          rm -f "$shim"
+        fi
+      done
+    }
+fi
+
+shopt -s nullglob
+
+# Create the prototype shim, then register shims for all known
+# executables.
+create_prototype_shim
+remove_outdated_shims
+# shellcheck disable=SC2046
+make_shims $(pyenv-versions --executables)
+
+
+# Allow plugins to register shims.
+OLDIFS="$IFS"
+IFS=$'\n' scripts=(`pyenv-hooks rehash`)
+IFS="$OLDIFS"
+
+for script in "${scripts[@]}"; do
+  source "$script"
+done
+
+install_registered_shims
+remove_stale_shims