#!/bin/bash
# Copyright 2018 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

#### CATEGORY=Run, inspect and debug
### symbolize backtraces and program locations provided as input on stdin

## usage: fx symbolize [--experimental] [--legacy] [-i IDS_TXT_FILE]
##                     [-r | --remote-symbols]
##
##    --experimental          use the experimental C++ symbolizer
##
##    --legacy                use the legacy Go symbolizer
##
##    -i IDS_TXT_FILE         specify an ids.txt file to be used
##
##    --remote-symbols|-r     attemp to resolve symbols using predefined remote
##                            symbol servers for symbols that cannot be resolved
##                            locally.
##
##    --auth                  (C++ symbolizer) start the authentication process.
##
##   Converts sybmolizer markup found in stdin to human readable using
##   local symbols (and remote if the --remote-symbols option is used).
##   This command is usually used on log output from either zx_log or syslog.
##   Anything that is not valid symbolizer markup is left alone. This is similar
##   to how c++filt works for demangling C++ symbols.
##
##   By default, `fx log` and `fx klog` automatically pipe their results into
##   this command.
##
##   --experimental / --legacy controls which implementation to use. The default
##   is to use the legacy Go symbolizer.
##
## Authentication
##
##   If the `--remote-symbols` option is specified, authentication for the symbol
##   server is needed.
##
##   When using the Go symbolizer, `fx symbolize` will fail if the current user
##   is not authenticated or doesn't have enough privileges on the symbol
##   servers. To ensure that the current user is properly authenticated, run:
##      `gcloud auth application-default login`
##
##   When using the C++ implementation, failed or missing authentication will be
##   silent. To authenticate, run:
##      `fx symbolize --experimental --auth`

source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/lib/vars.sh || exit $?

function go_symbolizer {
  fx-config-read
  source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/contrib/lib/symbol-index.sh || exit $?
  ensure-symbol-index-registered || fx-warn "Failed to register ${FUCHSIA_DIR} in symbol-index!"
  local symbolize="${HOST_OUT_DIR}/symbolize"
  if [[ ! -x "${symbolize}" ]]; then
    fx-error "Cannot execute '${symbolize}'. Try \`fx build\` first."
    exit 1
  fi
  local llvm_symbolizer="${PREBUILT_CLANG_DIR}/bin/llvm-symbolizer"
  local extra_args=()
  for i in "${ids_txt[@]}"; do
    extra_args+=(-ids-txt "${i}")
  done
  if [[ "${is_remote}" -eq 1 ]]; then
    extra_args+=(
      "-symbol-cache" "$HOME/.fuchsia-symbol-cache"
      "-symbol-server" "gs://fuchsia-artifacts/debug"
      "-symbol-server" "gs://fuchsia-artifacts-internal/debug"
      "-symbol-server" "gs://fuchsia-artifacts-release/debug"
    )
    trap '_code=$?; set +x; exit-with-warning ${_code}' ERR
  fi
  "${symbolize}" -llvm-symbolizer "${llvm_symbolizer}" -ids-rel "${extra_args[@]}"
}

function cpp_symbolizer {
  fx-config-read
  source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/contrib/lib/symbol-index.sh || exit $?
  ensure-symbol-index-registered || fx-warn "Failed to register ${FUCHSIA_DIR} in symbol-index!"
  local symbolizer="${HOST_OUT_DIR}/symbolizer"
  if [[ ! -x "${symbolizer}" ]]; then
    fx-error "Cannot execute '${symbolizer}'. Try \`fx build\` first."
    exit 1
  fi
  local extra_args=()
  for i in "${ids_txt[@]}"; do
    extra_args+=(--ids-txt "${i}")
  done
  if [[ "${is_remote}" -eq 1 ]]; then
    if [[ ! -f ~/.fuchsia/debug/googleapi_auth && ! -f ~/.config/gcloud/application_default_credentials.json ]]; then
      fx-error "Please authenticate first using \`fx symbolize --experimental --auth\`."
      exit 1
    fi
    extra_args+=(
      "--symbol-server" "gs://fuchsia-artifacts/debug"
      "--symbol-server" "gs://fuchsia-artifacts-internal/debug"
      "--symbol-server" "gs://fuchsia-artifacts-release/debug"
    )
  fi
  if [[ "${auth_mode}" -eq 1 ]]; then
    extra_args+=(--auth)
  fi
  "${symbolizer}" "${extra_args[@]}"
}

function exit-with-warning {
  local error_code="$1"
  if [[ "${error_code}" -ne 0 ]]; then
    fx-error "If you are having trouble with authentication, make sure you are" \
             "authenticated in gcloud and you have permission to access" \
             "the remote symbols servers.\nSee \`fx help symbolize\` for more information"
  fi
  exit ${error_code}
}

declare ids_txt=()
declare is_remote=0
declare auth_mode=0
declare use_experimental=1

while [[ $# -ne 0 ]]; do
  case "$1" in
  -h|--help)
    fx-command-help
    exit 0
    ;;
  --experimental)
    use_experimental=1
    ;;
  --legacy)
    use_experimental=0
    ;;
  --auth)
    auth_mode=1
    ;;
  -i)
    if [[ $# -lt 2 ]]; then
      fx-error Invalid syntax
      fx-command-help
      return 1
    fi
    ids_txt+=("$2")
    shift
    ;;
  --remote-symbols|-r)
    is_remote=1
    ;;
  *)
    fx-error Invalid syntax
    fx-command-help
    exit 1
  esac
  shift
done

if [[ "${is_remote}" -eq 1 ]]; then
  extra_args+=(
    "-symbol-cache" "$HOME/.fuchsia-symbol-cache"
    "-symbol-server" "gs://fuchsia-artifacts/debug"
    "-symbol-server" "gs://fuchsia-artifacts-internal/debug"
    "-symbol-server" "gs://fuchsia-artifacts-release/debug"
  )
fi

if [[ "${use_experimental}" -eq 1 ]]; then
  cpp_symbolizer
else
  go_symbolizer
fi