iankelling.org Git - automated-distro-installer/blob - fai/config/files/boot/bash-trace/DEFAULT

   1 #!/bin/bash
   2 # Copyright (C) 2019 Ian Kelling
   3 # SPDX-License-Identifier: AGPL-3.0-or-later
   4
   5 # meant to be sourced. copy/pasted from https://iankelling.org/git/?p=errhandle;a=summary
   6
   7 # Commentary: Bash stack trace and error handling functions. This file
   8 # is meant to be sourced. It loads some functions which you may want to
   9 # call manually (see the comments at the start of each one), and then
  10 # runs err-catch. See the README file for a slightly longer explanation.
  11
  12
  13 #######################################
  14 # Print stack trace
  15 #
  16 # usage: err-bash-trace [MESSAGE]
  17 #
  18 # This function is called by the other functions which print stack
  19 # traces.
  20 #
  21 # It does not show function args unless you first run:
  22 # shopt -s extdebug
  23 # which err-catch & err-print do for you.
  24 #
  25 # MESSAGE       Message to print just before the stack trace.
  26 #
  27 # _frame_start  Optional variable to set before calling. The frame to
  28 #               start printing on. default=1. Useful when printing from
  29 #               an ERR trap function to avoid printing that function.
  30 #######################################
  31 err-bash-trace() {
  32   local -i argc_index=0 frame i start=${_frame_start:-1}
  33   local source
  34   if [[ $1 ]]; then
  35     printf "%s\n" "$1"
  36   fi
  37   for ((frame=0; frame < ${#FUNCNAME[@]}; frame++)); do
  38     argc=${BASH_ARGC[frame]}
  39     argc_index+=$argc
  40     ((frame < start)) && continue
  41     if (( ${#BASH_SOURCE[@]} > 1 )); then
  42       source="${BASH_SOURCE[frame]}:${BASH_LINENO[frame-1]}:"
  43     fi
  44     printf "  from %sin \`%s" "$source" "${FUNCNAME[frame]}"
  45     if shopt extdebug >/dev/null; then
  46       for ((i=argc_index-1; i >= argc_index-argc; i--)); do
  47         printf " %s" "${BASH_ARGV[i]}"
  48       done
  49     fi
  50     echo \'
  51   done
  52   return 0
  53 }
  54
  55 #######################################
  56 # On error print stack trace and exit
  57 #
  58 # Globals:
  59 #   errcatch-cleanup  If set, this command will run just before exiting.
  60 #######################################
  61 err-catch() {
  62   set -E; shopt -s extdebug
  63   _err-trap() {
  64     err=$?
  65     exec >&2
  66     set +x
  67     local msg="${BASH_SOURCE[1]}:${BASH_LINENO[0]}: \`$BASH_COMMAND' returned $err"
  68     if (( ${#FUNCNAME[@]} > 2 )); then
  69       local _frame_start=2
  70       err-bash-trace "$msg"
  71     else
  72       echo "$msg"
  73     fi
  74     set -e # err trap does not work within an error trap
  75     if type -t errcatch-cleanup >/dev/null; then
  76       errcatch-cleanup
  77     fi
  78     echo "$0: exiting with status $err"
  79     exit $err
  80   }
  81   trap _err-trap ERR
  82   set -o pipefail
  83 }
  84
  85
  86 #######################################
  87 # For interactive shells: on error, print stack trace and return
  88 #
  89 # Globals:
  90 #   err_catch_ignore  Array containing glob patterns to test against filenames to ignore
  91 #                     errors from. Initialized to ignore bash-completion scripts on debian
  92 #                     based systems.
  93 #   _err_func_last  Used internally.
  94 #   _err_catch_err  Used internally.
  95 #   _err_catch_i    Used internally.
  96 #   _err_catch_ignore Used internally.
  97 #
  98 # misc: All shellcheck disables for this function are false positives.
  99 #######################################
 100 # shellcheck disable=SC2120
 101 err-catch-interactive() {
 102   err_catch_ignore=(
 103     '/etc/bash_completion.d/*'
 104   )
 105   # shellcheck disable=SC2034
 106   declare -i _err_func_last=0
 107   set -E; shopt -s extdebug
 108   # shellcheck disable=SC2154
 109   trap '_err_catch_err=$? _trap_bc="$BASH_COMMAND"
 110   _err_catch_ignore=false
 111   for _err_catch_i in "${err_catch_ignore[@]}"; do
 112     if [[ ${BASH_SOURCE[0]} == $_err_catch_i ]]; then
 113       _err_catch_ignore=true
 114       break
 115     fi
 116   done
 117   if ! $_err_catch_ignore; then
 118     if (( ${#FUNCNAME[@]} > _err_func_last )); then
 119       echo ERR: \`$_trap_bc'"\'"' returned $_err_catch_err
 120     fi
 121     _err_func_last=${#FUNCNAME[@]}
 122     if (( _err_func_last )); then
 123       printf "  from %s:%s:in \`%s" "${BASH_SOURCE[0]}" "$(declare -F "${FUNCNAME[0]}"|awk "{print \$2}")" "${FUNCNAME[0]}"
 124       if shopt extdebug >/dev/null; then
 125         for ((_err_catch_i=${BASH_ARGC[0]}-1; _err_catch_i >= 0; _err_catch_i--)); do
 126           printf " %s" "${BASH_ARGV[_err_catch_i]}"
 127         done
 128       fi
 129       echo '"\'"'
 130       return $_err_catch_err
 131     fi
 132   fi' ERR
 133   set -o pipefail
 134 }
 135
 136
 137 #######################################
 138 # Undoes err-catch/err-catch-interactive
 139 #######################################
 140 err-allow() {
 141   shopt -u extdebug
 142   set +E +o pipefail
 143   trap ERR
 144 }
 145
 146 #######################################
 147 # On error, print stack trace
 148 #######################################
 149 err-print() {
 150   # help: on errors: print stack trace
 151   #
 152   # This function depends on err-bash-trace.
 153
 154   set -E; shopt -s extdebug
 155   _err-trap() {
 156     err=$?
 157     exec >&2
 158     set +x
 159     echo "${BASH_SOURCE[1]}:${BASH_LINENO[0]}: \`$BASH_COMMAND' returned $err"
 160     err-bash-trace 2
 161   }
 162   trap _err-trap ERR
 163   set -o pipefail
 164 }
 165
 166
 167 #######################################
 168 # Print stack trace and exit
 169 #
 170 # Use this instead of the exit command to be more informative.
 171 #
 172 # usage: err-exit [EXIT_CODE] [MESSAGE]
 173 #
 174 # EXIT_CODE  Default is 1.
 175 # MESSAGE    Print MESSAGE to stderr. If only one of EXIT_CODE
 176 #            and MESSAGE is given, we consider it to be an
 177 #            exit code if it is a number.
 178 #######################################
 179 err-exit() {
 180   exec >&2
 181   code=1
 182   if [[ "$*" ]]; then
 183     if [[ ${1/[^0-9]/} == "$1" ]]; then
 184       code=$1
 185       if [[ $2 ]]; then
 186         printf '%s\n' "$2" >&2
 187       fi
 188     else
 189       printf '%s\n' "$0: $1" >&2
 190     fi
 191   fi
 192   echo "${BASH_SOURCE[1]}:${BASH_LINENO[0]}"
 193   err-bash-trace 2
 194   echo "$0: exiting with code $code"
 195   exit $err
 196 }
 197
 198 # We want this more often than not, so run it now.
 199 if [[ $- == *i* ]]; then
 200   err-catch-interactive
 201 else
 202   err-catch
 203 fi