After the error the other day with dash and glibc-2.3.6, I decided to
install dash[1] and give it a whirl as /bin/sh. Things went mostly
pretty well with respect to rogue bashisms throughout the system. I've
attached some patches to fix up the bootscripts while consulting the
POSIX spec on shells[2].
First patch is to eliminated "echo -[en]" since it's not always
supported by POSIX shells. I chose to use printf since it was a
builtin in dash. I didn't notice until later that it's not mentioned
in POSIX. And the executable printf is in /usr/bin. We can maintain
the same "echo -[en]" syntax by switching in /bin/echo everywhere,
too.
Second patch is just a tweak for boot_mesg. There's an excessive
pipeline using sed and grep to count the characters in the input
string. Fortunately, POSIX mandates that shells respect ${#var} to
return the length of the string. I chose to add 1 for an extra space
(the old way ended up with 2 spaces for some reason). $((...)) can be
used for arithmetic expansion according to POSIX.
Third patch is a combo because I couldn't keep the diffs separated in
the console script. First fix has to do with &> syntax. This is
equivalent to ">file 2>&1" according to bash(1), and that syntax is
supported by POSIX shells.
The second part has to do with trapping on ERR. Although `set -e' is
supported in POSIX, trapping is only mandated for signals. So, I just
sprinkled a bunch of conditionals through the console script to try to
achieve the same effect as the error trapping.
Let me know what you guys think.
--
Dan
[1] http://gondor.apana.org.au/~herbert/dash/
[2] http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
I don't know if printf is the right way to go since POSIX doesn't say
it needs to be a builtin from what I can see. If it's not builting,
then it's in /usr/bin, which isn't available at boot. All the shells
I've looked at have printf builtin, though.
Otherwise, we should use /bin/echo, which has the same semantics as
bash's echo.
Index: bootscripts/lfs/init.d/functions
===================================================================
--- bootscripts/lfs/init.d/functions (revision 7926)
+++ bootscripts/lfs/init.d/functions (working copy)
@@ -40,12 +40,12 @@
COL=$((${COLUMNS} - 8))
WCOL=$((${COL} - 2))
-## Set Cursor Position Commands, used via echo -e
+## Set Cursor Position Commands, used via printf
SET_COL="\\033[${COL}G" # at the $COL char
SET_WCOL="\\033[${WCOL}G" # at the $WCOL char
CURS_UP="\\033[1A\\033[0G" # Up one line, at the 0'th char
-## Set color commands, used via echo -e
+## Set color commands, used via printf
# Please consult `man console_codes for more information
# under the "ECMA-48 Set Graphics Rendition" section
#
@@ -79,13 +79,13 @@
#*******************************************************************************
boot_mesg()
{
- local ECHOPARM=""
+ local ENDCHAR='\n'
while true
do
case "${1}" in
-n)
- ECHOPARM=" -n "
+ ENDCHAR=
shift 1
;;
-*)
@@ -104,7 +104,7 @@
-e 's,.,.,g' -e 'l 1' | grep -c \$`"
# Print the message to the screen
- echo ${ECHOPARM} -e "${2}${1}"
+ printf "${2}${1}${ENDCHAR}"
}
@@ -117,28 +117,25 @@
boot_log()
{
# Left in for backwards compatibility
- echo -n ""
+ :
}
echo_ok()
{
- echo -n -e "${CURS_UP}${SET_COL}${BRACKET}[${SUCCESS} OK ${BRACKET}]"
- echo -e "${NORMAL}"
- boot_mesg_flush
+ printf "${CURS_UP}${SET_COL}${BRACKET}[${SUCCESS} OK ${BRACKET}]${NORMAL}\n"
+ boot_mesg_flush
}
echo_failure()
{
- echo -n -e "${CURS_UP}${SET_COL}${BRACKET}[${FAILURE} FAIL ${BRACKET}]"
- echo -e "${NORMAL}"
- boot_mesg_flush
+ printf "${CURS_UP}${SET_COL}${BRACKET}[${FAILURE} FAIL ${BRACKET}]${NORMAL}\n"
+ boot_mesg_flush
}
echo_warning()
{
- echo -n -e "${CURS_UP}${SET_COL}${BRACKET}[${WARNING} WARN ${BRACKET}]"
- echo -e "${NORMAL}"
- boot_mesg_flush
+ printf "${CURS_UP}${SET_COL}${BRACKET}[${WARNING} WARN ${BRACKET}]${NORMAL}\n"
+ boot_mesg_flush
}
print_error_msg()
@@ -209,20 +206,20 @@
# may call it this way.
case "${2}" in
running)
- echo -e -n "${CURS_UP}"
- echo -e -n "\\033[${STRING_LENGTH}G "
+ printf "${CURS_UP}"
+ printf "\\033[${STRING_LENGTH}G "
boot_mesg "Already running." ${WARNING}
echo_warning
;;
not_running)
- echo -e -n "${CURS_UP}"
- echo -e -n "\\033[${STRING_LENGTH}G "
+ printf "${CURS_UP}"
+ printf "\\033[${STRING_LENGTH}G "
boot_mesg "Not running." ${WARNING}
echo_warning
;;
not_available)
- echo -e -n "${CURS_UP}"
- echo -e -n "\\033[${STRING_LENGTH}G "
+ printf "${CURS_UP}"
+ printf "\\033[${STRING_LENGTH}G "
boot_mesg "Not available." ${WARNING}
echo_warning
;;
@@ -278,18 +275,18 @@
getpids "${1}"
if [ -n "${pidlist}" ]; then
- echo -e "${INFO}${base} is running with Process"\
- "ID(s) ${pidlist}.${NORMAL}"
+ printf "${INFO}${base} is running with Process"\
+ "ID(s) ${pidlist}.${NORMAL}\n"
else
if [ -n "${base}" -a -e "/var/run/${base}.pid" ]; then
- echo -e "${WARNING}${1} is not running but"\
- "/var/run/${base}.pid exists.${NORMAL}"
+ printf "${WARNING}${1} is not running but"\
+ "/var/run/${base}.pid exists.${NORMAL}\n"
else
if [ -n "${PIDFILE}" -a -e "${PIDFILE}" ]; then
- echo -e "${WARNING}${1} is not running"\
- "but ${PIDFILE} exists.${NORMAL}"
+ printf "${WARNING}${1} is not running" \
+ "but ${PIDFILE} exists.${NORMAL}\n"
else
- echo -e "${INFO}${1} is not running.${NORMAL}"
+ printf "${INFO}${1} is not running.${NORMAL}\n"
fi
fi
fi
@@ -627,15 +624,15 @@
#
# Outputs: Text output to screen
#
-# Dependencies: echo
+# Dependencies: printf
#
# Todo: logging
#
#*******************************************************************************
log_success_msg()
{
- echo -n -e "[EMAIL PROTECTED]"
- echo -e "${SET_COL}""${BRACKET}""[""${SUCCESS}"" OK ""${BRACKET}""]""${NORMAL}"
+ printf "[EMAIL PROTECTED]"
+ printf "${SET_COL}""${BRACKET}""[""${SUCCESS}"" OK ""${BRACKET}""]""${NORMAL}\n"
return 0
}
@@ -648,14 +645,14 @@
#
# Outputs: Text output to screen
#
-# Dependencies: echo
+# Dependencies: printf
#
# Todo: logging
#
#*******************************************************************************
log_failure_msg() {
- echo -n -e "[EMAIL PROTECTED]"
- echo -e "${SET_COL}""${BRACKET}""[""${FAILURE}"" FAIL ""${BRACKET}""]""${NORMAL}"
+ printf "[EMAIL PROTECTED]"
+ printf "${SET_COL}""${BRACKET}""[""${FAILURE}"" FAIL ""${BRACKET}""]""${NORMAL}\n"
return 0
}
@@ -674,8 +671,8 @@
#
#*******************************************************************************
log_warning_msg() {
- echo -n -e "[EMAIL PROTECTED]"
- echo -e "${SET_COL}""${BRACKET}""[""${WARNING}"" WARN ""${BRACKET}""]""${NORMAL}"
+ printf "[EMAIL PROTECTED]"
+ printf "${SET_COL}""${BRACKET}""[""${WARNING}"" WARN ""${BRACKET}""]""${NORMAL}\n"
return 0
}
Index: bootscripts/lfs/init.d/console
===================================================================
--- bootscripts/lfs/init.d/console (revision 7926)
+++ bootscripts/lfs/init.d/console (working copy)
@@ -42,8 +42,8 @@
# Figure out the command to set the console into the
# desired mode
is_true "${UNICODE}" &&
- MODE_COMMAND="echo -en '\033%G' && kbd_mode -u" ||
- MODE_COMMAND="echo -en '[EMAIL PROTECTED](K' && kbd_mode -a"
+ MODE_COMMAND="printf '\033%G' && kbd_mode -u" ||
+ MODE_COMMAND="printf '[EMAIL PROTECTED](K' && kbd_mode -a"
# On framebuffer consoles, font has to be set for each vt in
# UTF-8 mode. This doesn't hurt in non-UTF-8 mode also.
Just a tweak to use arithmetic expansion and string length, which are
both mandated by POSIX, rather than spawning two processes every time
boot_mesg() is called.
Index: bootscripts/lfs/init.d/functions
===================================================================
--- bootscripts/lfs/init.d/functions (revision 7926)
+++ bootscripts/lfs/init.d/functions (working copy)
@@ -99,9 +99,8 @@
done
## Figure out the length of what is to be printed to be used
- ## for warning messges.
- STRING_LENGTH="`echo "${1}" | sed \
- -e 's,.,.,g' -e 'l 1' | grep -c \$`"
+ ## for warning messges.
+ STRING_LENGTH=$((${#1} + 1))
# Print the message to the screen
echo ${ECHOPARM} -e "${2}${1}"
Two fixes here since their diffs blend together.
1. POSIX says that shells only need to trap on signals. Trapping on
ERR isn't always supported. I've sprinkled in conditionals to
set the failed variable in spots that seemed appropriate for
checking errors.
2. &> redirection is not supported in POSIX. Fortunately, it's
equivalent to >word 2>&1 according to bash(1).
Index: bootscripts/lfs/init.d/console
===================================================================
--- bootscripts/lfs/init.d/console (revision 7926)
+++ bootscripts/lfs/init.d/console (working copy)
@@ -29,7 +29,6 @@
}
failed=0
-trap failed=1 ERR
case "${1}" in
start)
@@ -63,14 +62,19 @@
grep -o '\btty[[:digit:]]*\b'`
do
openvt -f -w -c ${TTY#tty} -- \
- /bin/sh -c "${MODE_COMMAND}"
+ /bin/sh -c "${MODE_COMMAND}" || failed=1
done
# Set the font (if not already set above) and the keymap
- is_true "${USE_FB}" || [ -z "${FONT}" ] || setfont $FONT
- [ -z "${KEYMAP}" ] || loadkeys ${KEYMAP} &>/dev/null
+ is_true "${USE_FB}" || [ -z "${FONT}" ] ||
+ setfont $FONT ||
+ failed=1
+ [ -z "${KEYMAP}" ] ||
+ loadkeys ${KEYMAP} >/dev/null 2>&1 ||
+ failed=1
[ -z "${KEYMAP_CORRECTIONS}" ] ||
- loadkeys ${KEYMAP_CORRECTIONS} &>/dev/null
+ loadkeys ${KEYMAP_CORRECTIONS} >/dev/null 2>&1 ||
+ failed=1
# Linux kernel generates wrong bytes when composing
# in Unicode mode. That's why we disable dead keys in Unicode
@@ -82,11 +86,14 @@
[ -n "$BROKEN_COMPOSE" ] || BROKEN_COMPOSE="$UNICODE"
! is_true "$BROKEN_COMPOSE" ||
- echo "" | loadkeys -c &>/dev/null
+ echo "" | loadkeys -c >/dev/null 2>&1 ||
+ failed=1
# Convert the keymap from $LEGACY_CHARSET to UTF-8
[ -z "$LEGACY_CHARSET" ] ||
- dumpkeys -c "$LEGACY_CHARSET" | loadkeys -u &>/dev/null
+ dumpkeys -c "$LEGACY_CHARSET" |
+ loadkeys -u >/dev/null 2>&1 ||
+ failed=1
# If any of the commands above failed, the trap at the
# top would set $failed to 1
Index: bootscripts/lfs/init.d/mountkernfs
===================================================================
--- bootscripts/lfs/init.d/mountkernfs (revision 7926)
+++ bootscripts/lfs/init.d/mountkernfs (working copy)
@@ -19,12 +19,12 @@
start)
boot_mesg -n "Mounting kernel-based file systems:" ${INFO}
- if ! mountpoint /proc &> /dev/null; then
+ if ! mountpoint /proc >/dev/null 2>&1; then
boot_mesg -n " /proc" ${NORMAL}
mount -n /proc || failed=1
fi
- if ! mountpoint /sys &> /dev/null; then
+ if ! mountpoint /sys >/dev/null 2>&1; then
boot_mesg -n " /sys" ${NORMAL}
mount -n /sys || failed=1
fi
--
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