Bash,runfiles: add runfiles library

See https://github.com/bazelbuild/bazel/issues/4460

Change-Id: I35a0b12ac17fe8bfdce3c7ba8c0dfddb35df7e28

Closes #5014.

Change-Id: I35a0b12ac17fe8bfdce3c7ba8c0dfddb35df7e28
PiperOrigin-RevId: 193010997

3 files changed, 307 insertions, 0 deletions

diff --git a/tools/bash/runfiles/BUILD b/tools/bash/runfiles/BUILD
index 964802ce9b..adec4cef86 100644
--- a/tools/bash/runfiles/BUILD
+++ b/tools/bash/runfiles/BUILD
@@ -16,10 +16,23 @@ filegroup(
     name = "embedded_tools",
     srcs = [
         "BUILD.tools",
+        "runfiles.bash",
     ],
     visibility = ["//tools/bash:__pkg__"],
 )
 
+sh_library(
+    name = "runfiles_lib",
+    testonly = 1,
+    srcs = ["runfiles.bash"],
+)
+
+sh_test(
+    name = "runfiles_test",
+    srcs = ["runfiles_test.bash"],
+    deps = [":runfiles_lib"],
+)
+
 test_suite(
     name = "windows_tests",
     tags = [
diff --git a/tools/bash/runfiles/runfiles.bash b/tools/bash/runfiles/runfiles.bash
new file mode 100644
index 0000000000..d56a835bfa
--- /dev/null
+++ b/tools/bash/runfiles/runfiles.bash
@@ -0,0 +1,113 @@
+#!/bin/bash
+#
+# Copyright 2018 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This Bash script defines functions to handle sh_binary/sh_test runfiles.
+#
+# REQUIREMENTS:
+# - The RUNFILES_MANIFEST_FILE and/or the RUNFILES_DIR environment variable must
+#   be set to the absolute path of the runfiles manifest or the
+#   <rulename>.runfiles directory, respectively.
+# - If RUNFILES_MANIFEST_ONLY=1 is set, then RUNFILES_MANIFEST_FILE must be set
+#   to the absolute path of the runfiles manifest. RUNFILES_DIR may be unset in
+#   this case.
+# - If RUNFILES_LIB_DEBUG=1 is set, the script will print errors to stderr.
+
+case "$(uname -s | tr [:upper:] [:lower:])" in
+msys*|mingw*|cygwin*)
+  # matches an absolute Windows path
+  _rlocation_isabs_pattern="^[a-zA-Z]:[/\\]"
+  ;;
+*)
+  # matches an absolute Unix path
+  _rlocation_isabs_pattern="^/.*"
+  ;;
+esac
+
+# Prints to stdout the runtime location of a data-dependency.
+function rlocation() {
+  if [[ "$1" =~ $_rlocation_isabs_pattern ]]; then
+    # If the path is absolute, print it as-is.
+    echo $1
+  elif [[ "$1" =~ \.\. ]]; then
+    if [[ "${RUNFILES_LIB_DEBUG:-}" == 1 ]]; then
+      echo >&2 "ERROR[runfiles.bash]: rlocation($1): contains uplevel reference"
+    fi
+    return 1
+  elif [[ "$1" == \\* ]]; then
+    if [[ "${RUNFILES_LIB_DEBUG:-}" == 1 ]]; then
+      echo >&2 "ERROR[runfiles.bash]: rlocation($1): absolute path without" \
+               "drive name"
+    fi
+    return 1
+  else
+    if [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 ]]; then
+      if [[ -n "${RUNFILES_MANIFEST_FILE:-}" \
+            && -f "${RUNFILES_MANIFEST_FILE}" ]]; then
+        grep -m1 "^$1 " "${RUNFILES_MANIFEST_FILE}" | cut -d ' ' -f 2- \
+          || return 1
+      else
+        if [[ "${RUNFILES_LIB_DEBUG:-}" == 1 ]]; then
+          echo >&2 "ERROR[runfiles.bash]: trying to use manifest-based" \
+                   "runfiles but RUNFILES_MANIFEST_FILE is unset or" \
+                   "non-existent" \
+                   "(RUNFILES_MANIFEST_ONLY=\"${RUNFILES_MANIFEST_ONLY:-}\"," \
+                   "RUNFILES_DIR=\"${RUNFILES_DIR:-}\")"
+        fi
+        return 1
+      fi
+    elif [[ -n "${RUNFILES_DIR:-}" && -d "${RUNFILES_DIR}" ]]; then
+      echo "${RUNFILES_DIR}/$1"
+    else
+      if [[ "${RUNFILES_LIB_DEBUG:-}" == 1 ]]; then
+        echo >&2 "ERROR[runfiles.bash]: trying to use directory-based" \
+                 "runfiles but RUNFILES_DIR is unset or non-existent" \
+                 "(RUNFILES_MANIFEST_ONLY=\"${RUNFILES_MANIFEST_ONLY:-}\"," \
+                 "RUNFILES_MANIFEST_FILE=\"${RUNFILES_MANIFEST_FILE:-}\")"
+      fi
+      return 1
+    fi
+  fi
+}
+export -f rlocation
+
+# Exports the environment variables that subprocesses may need to use runfiles.
+# If a subprocess is a Bazel-built binary rule that also uses the runfiles
+# libraries under @bazel_tools//tools/bash/runfiles, then that binary needs
+# these envvars in order to initialize its own runfiles library.
+function runfiles_export_envvars() {
+  if [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 ]]; then
+    if [[ -z "${RUNFILES_MANIFEST_FILE:-}" \
+          && ! -f "$RUNFILES_MANIFEST_FILE" ]]; then
+      return 1
+    fi
+    if [[ -z "${RUNFILES_DIR:-}" ]]; then
+      if [[ "$RUNFILES_MANIFEST_FILE" == */MANIFEST \
+            && -d "${RUNFILES_MANIFEST_FILE%/MANIFEST}" ]]; then
+        export RUNFILES_DIR="${RUNFILES_MANIFEST_FILE%/MANIFEST}"
+      elif [[ "$RUNFILES_MANIFEST_FILE" == *runfiles_manifest \
+            && -d "${RUNFILES_MANIFEST_FILE%_manifest}" ]]; then
+        export RUNFILES_DIR="${RUNFILES_MANIFEST_FILE%_manifest}"
+      fi
+    fi
+  fi
+  # No need to define anything if RUNFILES_MANIFEST_ONLY is not 1: it makes no
+  # difference whether RUNFILES_DIR is defined or not.
+
+  export RUNFILES_MANIFEST_FILE="${RUNFILES_MANIFEST_FILE:-}"
+  export RUNFILES_DIR="${RUNFILES_DIR:-}"
+  export JAVA_RUNFILES="${RUNFILES_DIR:-}"
+}
+export -f runfiles_export_envvars
diff --git a/tools/bash/runfiles/runfiles_test.bash b/tools/bash/runfiles/runfiles_test.bash
new file mode 100644
index 0000000000..3d6dd8885c
--- /dev/null
+++ b/tools/bash/runfiles/runfiles_test.bash
@@ -0,0 +1,181 @@
+#!/bin/bash
+#
+# Copyright 2018 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+set -euo pipefail
+
+function _log_base() {
+  prefix=$1
+  shift
+  echo >&2 "${prefix}[$(basename "${BASH_SOURCE[0]}"):${BASH_LINENO[1]} ($(date "+%H:%M:%S %z"))] $*"
+}
+
+function fail() {
+  _log_base "FAILED" "$@"
+  exit 1
+}
+
+function log_fail() {
+  # non-fatal version of fail()
+  _log_base "FAILED" $*
+}
+
+function log_info() {
+  _log_base "INFO" $*
+}
+
+which uname >&/dev/null || fail "cannot locate GNU coreutils"
+
+case "$(uname -s | tr [:upper:] [:lower:])" in
+msys*|mingw*|cygwin*)
+  function is_windows() { true; }
+  ;;
+*)
+  function is_windows() { false; }
+  ;;
+esac
+
+function find_runfiles_lib() {
+  # Unset existing definitions of the functions we want to test.
+  if type rlocation >&/dev/null; then
+    unset rlocation
+    unset runfiles_export_envvars
+  fi
+
+  if [[ "${RUNFILES_MANIFEST_ONLY:-}" == "1" ]]; then
+    grep -m1 "^io_bazel/tools/bash/runfiles/runfiles.bash" \
+             "${RUNFILES_MANIFEST_FILE}" | cut -d ' ' -f 2-
+  elif [[ -n "${RUNFILES_DIR:-}" && -d "$RUNFILES_DIR" ]]; then
+    echo "${RUNFILES_DIR}/io_bazel/tools/bash/runfiles/runfiles.bash"
+  else
+    echo >&2 "ERROR: cannot find //tools/bash/runfiles:runfiles.bash"
+    return 1
+  fi
+}
+
+function test_rlocation_call_requires_no_envvars() {
+  export RUNFILES_DIR=mock/runfiles
+  export RUNFILES_MANIFEST_FILE=
+  export RUNFILES_MANIFEST_ONLY=
+  source "$runfiles_lib_path" || fail
+}
+
+function test_rlocation_argument_validation() {
+  export RUNFILES_DIR=
+  export RUNFILES_MANIFEST_FILE=
+  export RUNFILES_MANIFEST_ONLY=
+  source "$runfiles_lib_path"
+
+  # Test invalid inputs to make sure rlocation catches these.
+  if (rlocation "foo/.." >&/dev/null); then
+    fail
+  fi
+  if (rlocation "\\foo" >&/dev/null); then
+    fail
+  fi
+}
+
+function test_rlocation_abs_path() {
+  export RUNFILES_DIR=
+  export RUNFILES_MANIFEST_FILE=
+  export RUNFILES_MANIFEST_ONLY=
+  source "$runfiles_lib_path"
+
+  if is_windows; then
+    [[ "$(rlocation "c:/Foo")" == "c:/Foo" ]] || fail
+    [[ "$(rlocation "c:\\Foo")" == "c:\\Foo" ]] || fail
+  else
+    [[ "$(rlocation "/Foo")" == "/Foo" ]] || fail
+  fi
+}
+
+function test_init_manifest_based_runfiles() {
+  local tmpdir="$(mktemp -d $TEST_TMPDIR/tmp.XXXXXXXX)"
+  cat > $tmpdir/foo.runfiles_manifest << 'EOF'
+a/b c/d
+e/f g h
+EOF
+
+  export RUNFILES_DIR=
+  export RUNFILES_MANIFEST_FILE=$tmpdir/foo.runfiles_manifest
+  export RUNFILES_MANIFEST_ONLY=1
+  source "$runfiles_lib_path"
+
+  [[ -z "$(rlocation a)" ]] || fail
+  [[ "$(rlocation a/b)" == "c/d" ]] || fail
+  [[ "$(rlocation e/f)" == "g h" ]] || fail
+  [[ -z "$(rlocation c/d)" ]] || fail
+}
+
+function test_manifest_based_envvars() {
+  local tmpdir="$(mktemp -d $TEST_TMPDIR/tmp.XXXXXXXX)"
+  echo "a b" > $tmpdir/foo.runfiles_manifest
+
+  export RUNFILES_DIR=
+  export RUNFILES_MANIFEST_FILE=$tmpdir/foo.runfiles_manifest
+  export RUNFILES_MANIFEST_ONLY=1
+  mkdir -p $tmpdir/foo.runfiles
+  source "$runfiles_lib_path"
+
+  runfiles_export_envvars
+  [[ "${RUNFILES_DIR:-}" == "$tmpdir/foo.runfiles" ]] || fail
+  [[ "${RUNFILES_MANIFEST_FILE:-}" == "$tmpdir/foo.runfiles_manifest" ]] || fail
+  [[ "${RUNFILES_MANIFEST_ONLY:-}" == 1 ]] || fail
+}
+
+function test_init_directory_based_runfiles() {
+  local tmpdir="$(mktemp -d $TEST_TMPDIR/tmp.XXXXXXXX)"
+
+  export RUNFILES_DIR=${tmpdir}/mock/runfiles
+  export RUNFILES_MANIFEST_FILE=
+  export RUNFILES_MANIFEST_ONLY=
+  source "$runfiles_lib_path"
+
+  mkdir -p "$RUNFILES_DIR"
+  [[ "$(rlocation a)" == */mock/runfiles/a ]] || fail
+  [[ "$(rlocation a/b)" == *mock/runfiles/a/b ]] || fail
+}
+
+function test_directory_based_envvars() {
+  export RUNFILES_DIR=mock/runfiles
+  export RUNFILES_MANIFEST_FILE=
+  export RUNFILES_MANIFEST_ONLY=
+  source "$runfiles_lib_path"
+
+  runfiles_export_envvars
+  [[ "${RUNFILES_DIR:-}" == "mock/runfiles" ]] || fail
+  [[ -z "${RUNFILES_MANIFEST_FILE:-}" ]] || fail
+  [[ -z "${RUNFILES_MANIFEST_ONLY:-}" ]] || fail
+}
+
+function main() {
+  local -r manifest_only="${RUNFILES_MANIFEST_ONLY:-}"
+  local -r manifest_file="${RUNFILES_MANIFEST_FILE:-}"
+  local -r dir="${RUNFILES_DIR:-}"
+  local -r runfiles_lib_path=$(find_runfiles_lib)
+
+  local -r tests=$(declare -F | grep " -f test" | awk '{print $3}')
+  local failure=0
+  for t in $tests; do
+    export RUNFILES_MANIFEST_ONLY="$manifest_only"
+    export RUNFILES_MANIFEST_FILE="$manifest_file"
+    export RUNFILES_DIR="$dir"
+    if ! ($t); then
+      failure=1
+    fi
+  done
+  return $failure
+}
+
+main