[PATCH] test: Fix printf error when debug is enabled
Running test pasta/tcp with debug enabled would get stuck with
below error:
+ printf 'DEBUG: ns socat -u OPEN:__BASEPATH__/big.bin TCP6:[__GW6__%__IFNAME__]:10003\n'
lib/term: line 38: printf: `_': invalid format character
The error occurs because printf interprets the % character as the
start of a format specifier, and the following '_' isn't one of
them.
Fix it by replacing 'printf "${*}\n"' with 'printf "%s\n" "$*"'.
Also update the docstring.
Link: https://bugs.passt.top/show_bug.cgi?id=154
Fixes: de28c20d8051 ("test: Update lib/term for clearer output when DEBUG is enabled")
Signed-off-by: Yumei Huang
On Mon, Sep 29, 2025 at 02:30:14PM +0800, Yumei Huang wrote:
Running test pasta/tcp with debug enabled would get stuck with below error:
+ printf 'DEBUG: ns socat -u OPEN:__BASEPATH__/big.bin TCP6:[__GW6__%__IFNAME__]:10003\n' lib/term: line 38: printf: `_': invalid format character
The error occurs because printf interprets the % character as the start of a format specifier, and the following '_' isn't one of them.
Fix it by replacing 'printf "${*}\n"' with 'printf "%s\n" "$*"'. Also update the docstring.
Link: https://bugs.passt.top/show_bug.cgi?id=154 Fixes: de28c20d8051 ("test: Update lib/term for clearer output when DEBUG is enabled") Signed-off-by: Yumei Huang
Reviewed-by: David Gibson
--- test/lib/term | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/test/lib/term b/test/lib/term index 6400746..2293474 100755 --- a/test/lib/term +++ b/test/lib/term @@ -29,32 +29,32 @@ PR_NC='\033[0m' PR_DELAY_INIT=100 # ms
# info() - Highlight test log pane, print message to it and to log file -# $@: Message to print +# $*: Message to print info() { tmux select-pane -t ${PANE_INFO} - printf "${*}\n" >> $STATEBASE/log_pipe - printf "${*}\n" >> "${LOGFILE}" + printf "%s\n" "$*" >> $STATEBASE/log_pipe + printf "%s\n" "$*" >> "${LOGFILE}" }
# info_n() - Highlight, print message to pane and to log file without newline -# $@: Message to print +# $*: Message to print info_n() { tmux select-pane -t ${PANE_INFO} - printf "${*}" >> $STATEBASE/log_pipe - printf "${*}" >> "${LOGFILE}" + printf "%s\n" "$*" >> $STATEBASE/log_pipe + printf "%s\n" "$*" >> "${LOGFILE}" }
# info_nolog() - Highlight test log pane, print message to it -# $@: Message to print +# $*: Message to print info_nolog() { tmux select-pane -t ${PANE_INFO} - printf "${*}\n" >> $STATEBASE/log_pipe + printf "%s\n" "$*" >> $STATEBASE/log_pipe }
# info_nolog() - Print message to log file -# $@: Message to print +# $*: Message to print log() { - printf "${*}\n" >> "${LOGFILE}" + printf "%s\n" "$*" >> "${LOGFILE}" }
# info_nolog_n() - Send message to pane without highlighting it, without newline @@ -363,8 +363,8 @@ status_test_start() { info_check() { switch_pane ${PANE_INFO}
- printf "${PR_YELLOW}?${PR_NC} ${*}" >> $STATEBASE/log_pipe - printf "? ${*}" >> "${LOGFILE}" + printf "%s" "${PR_YELLOW}?${PR_NC} ${*}" >> $STATEBASE/log_pipe + printf "? %s" "${*}" >> "${LOGFILE}" }
# info_check_passed() - Display and log a new line when a check passes -- 2.47.0
-- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson
On Mon, 29 Sep 2025 14:30:14 +0800
Yumei Huang
Running test pasta/tcp with debug enabled would get stuck with below error:
+ printf 'DEBUG: ns socat -u OPEN:__BASEPATH__/big.bin TCP6:[__GW6__%__IFNAME__]:10003\n' lib/term: line 38: printf: `_': invalid format character
The error occurs because printf interprets the % character as the start of a format specifier, and the following '_' isn't one of them.
Fix it by replacing 'printf "${*}\n"' with 'printf "%s\n" "$*"'.
I'm not sure why, but this breaks colour highlights for me. Instead of seeing a part of this message in blue, now I get: Test layout: \033[1;34msingle passt instance with guest\033[0m.\n I can look into it if it only happens for me, or if needed. By the way (I'm not sure if it's related), I used curly brackets everywhere to unambiguously distinguish names of variables, and '*' is a name. The curly brackets are almost always optional, see POSIX.1-2024 for the cases where they are needed: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#ta... ...to avoid possible issues, I just used them everywhere, and I think it would be good to keep this consistent. That is, the $* should remain as ${*}. -- Stefano
On Tue, Sep 30, 2025 at 12:24:17AM +0200, Stefano Brivio wrote:
On Mon, 29 Sep 2025 14:30:14 +0800 Yumei Huang
wrote: Running test pasta/tcp with debug enabled would get stuck with below error:
+ printf 'DEBUG: ns socat -u OPEN:__BASEPATH__/big.bin TCP6:[__GW6__%__IFNAME__]:10003\n' lib/term: line 38: printf: `_': invalid format character
The error occurs because printf interprets the % character as the start of a format specifier, and the following '_' isn't one of them.
Fix it by replacing 'printf "${*}\n"' with 'printf "%s\n" "$*"'.
I'm not sure why, but this breaks colour highlights for me. Instead of seeing a part of this message in blue, now I get:
Test layout: \033[1;34msingle passt instance with guest\033[0m.\n
I can look into it if it only happens for me, or if needed.
Oh, that's interesting. I believe the colouring has been broken forever on Fedora, but I never got around to looking into it. Figuring this out might reveal why. Maybe. I realised I think I know why: those colour codes rely on turning "\033" into a terminal escape. printf(1) will do that in the format string, but not in %s parameters $ printf "a\tb%sc\n " "\t" a b\tc We can fix this either by moving the escape codes back into the format string, or using %b instead of %s, which explicitly interprets string escape codes. -- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson
On Tue, Sep 30, 2025 at 8:23 AM David Gibson
On Tue, Sep 30, 2025 at 12:24:17AM +0200, Stefano Brivio wrote:
On Mon, 29 Sep 2025 14:30:14 +0800 Yumei Huang
wrote: Running test pasta/tcp with debug enabled would get stuck with below error:
+ printf 'DEBUG: ns socat -u OPEN:__BASEPATH__/big.bin TCP6:[__GW6__%__IFNAME__]:10003\n' lib/term: line 38: printf: `_': invalid format character
The error occurs because printf interprets the % character as the start of a format specifier, and the following '_' isn't one of them.
Fix it by replacing 'printf "${*}\n"' with 'printf "%s\n" "$*"'.
I'm not sure why, but this breaks colour highlights for me. Instead of seeing a part of this message in blue, now I get:
Test layout: \033[1;34msingle passt instance with guest\033[0m.\n
I can look into it if it only happens for me, or if needed.
Oh, that's interesting. I believe the colouring has been broken forever on Fedora, but I never got around to looking into it.
Well, the color worked fine on fedora before I changed to using "%s".
Figuring this out might reveal why. Maybe.
I realised I think I know why: those colour codes rely on turning "\033" into a terminal escape. printf(1) will do that in the format string, but not in %s parameters
$ printf "a\tb%sc\n " "\t" a b\tc
We can fix this either by moving the escape codes back into the format string, or using %b instead of %s, which explicitly interprets string escape codes.
Yes, %b fixes this. I will send v2 to update it and the brackets. Thanks.
-- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson
-- Thanks, Yumei Huang
On Tue, 30 Sep 2025 10:23:39 +1000
David Gibson
On Tue, Sep 30, 2025 at 12:24:17AM +0200, Stefano Brivio wrote:
On Mon, 29 Sep 2025 14:30:14 +0800 Yumei Huang
wrote: Running test pasta/tcp with debug enabled would get stuck with below error:
+ printf 'DEBUG: ns socat -u OPEN:__BASEPATH__/big.bin TCP6:[__GW6__%__IFNAME__]:10003\n' lib/term: line 38: printf: `_': invalid format character
The error occurs because printf interprets the % character as the start of a format specifier, and the following '_' isn't one of them.
Fix it by replacing 'printf "${*}\n"' with 'printf "%s\n" "$*"'.
I'm not sure why, but this breaks colour highlights for me. Instead of seeing a part of this message in blue, now I get:
Test layout: \033[1;34msingle passt instance with guest\033[0m.\n
I can look into it if it only happens for me, or if needed.
Oh, that's interesting. I believe the colouring has been broken forever on Fedora, but I never got around to looking into it. Figuring this out might reveal why. Maybe.
I realised I think I know why: those colour codes rely on turning "\033" into a terminal escape. printf(1) will do that in the format string, but not in %s parameters
$ printf "a\tb%sc\n " "\t" a b\tc
We can fix this either by moving the escape codes back into the format string, or using %b instead of %s, which explicitly interprets string escape codes.
Oh, I didn't know about %b, nice. It's also in POSIX.1-2024, see point 7. here: https://pubs.opengroup.org/onlinepubs/9799919799/utilities/printf.html#tag_2... ...side note for Yumei: the whole test suite _should_ be POSIX shell, that is, it doesn't rely on specific shell (e.g. Bash) implementations. For example, on Debian, Ubuntu, and others, the default shell for non-interactive usage (not what you have on terminal, but what executes scripts) is dash: https://wiki.ubuntu.com/DashAsBinSh https://wiki.archlinux.org/title/Dash So, if it's described in the POSIX specification (the one I just linked) it will almost certainly work everywhere. If not, it might break (but not necessarily). -- Stefano
participants (3)
-
David Gibson
-
Stefano Brivio
-
Yumei Huang