From 6b02121d88839c362d16cad877f732c701b11a67 Mon Sep 17 00:00:00 2001 From: jilles Date: Sun, 24 Feb 2019 21:05:13 +0000 Subject: [PATCH] sh: Add set -o pipefail The pipefail option allows checking the exit status of all commands in a pipeline more easily, at a limited cost of complexity in sh itself. It works similarly to the option in bash, ksh93 and mksh. Like ksh93 and unlike bash and mksh, the state of the option is saved when a pipeline is started. Therefore, even in the case of commands like A | B & a later change of the option does not change the exit status, the same way (A | B) & works. Since SIGPIPE is not handled specially, more work in the script is required for a proper exit status for pipelines containing commands such as head that may terminate successfully without reading all input. This can be something like ( cmd1 r=$? if [ "$r" -gt 128 ] && [ "$(kill -l "$r")" = PIPE ]; then exit 0 else exit "$r" fi ) | head PR: 224270 Relnotes: yes --- bin/sh/jobs.c | 23 ++++++++++++++++++++--- bin/sh/options.h | 4 +++- bin/sh/sh.1 | 25 ++++++++++++++++++++----- bin/sh/tests/execution/Makefile | 7 +++++++ bin/sh/tests/execution/pipefail1.0 | 4 ++++ bin/sh/tests/execution/pipefail2.42 | 4 ++++ bin/sh/tests/execution/pipefail3.42 | 4 ++++ bin/sh/tests/execution/pipefail4.42 | 4 ++++ bin/sh/tests/execution/pipefail5.42 | 5 +++++ bin/sh/tests/execution/pipefail6.42 | 6 ++++++ bin/sh/tests/execution/pipefail7.0 | 5 +++++ 11 files changed, 82 insertions(+), 9 deletions(-) create mode 100644 bin/sh/tests/execution/pipefail1.0 create mode 100644 bin/sh/tests/execution/pipefail2.42 create mode 100644 bin/sh/tests/execution/pipefail3.42 create mode 100644 bin/sh/tests/execution/pipefail4.42 create mode 100644 bin/sh/tests/execution/pipefail5.42 create mode 100644 bin/sh/tests/execution/pipefail6.42 create mode 100644 bin/sh/tests/execution/pipefail7.0 diff --git a/bin/sh/jobs.c b/bin/sh/jobs.c index 50cf2ca959fd..2475787c1da9 100644 --- a/bin/sh/jobs.c +++ b/bin/sh/jobs.c @@ -105,6 +105,7 @@ struct job { char changed; /* true if status has changed */ char foreground; /* true if running in the foreground */ char remembered; /* true if $! referenced */ + char pipefail; /* pass any non-zero status */ #if JOBS char jobctl; /* job running under job control */ struct job *next; /* job used after this one */ @@ -144,6 +145,7 @@ static void setcurjob(struct job *); static void deljob(struct job *); static struct job *getcurjob(struct job *); #endif +static int getjobstatus(const struct job *); static void printjobcmd(struct job *); static void showjob(struct job *, int); @@ -341,6 +343,20 @@ jobscmd(int argc __unused, char *argv[] __unused) return (0); } +static int getjobstatus(const struct job *jp) +{ + int i, status; + + if (!jp->pipefail) + return (jp->ps[jp->nprocs - 1].status); + for (i = jp->nprocs - 1; i >= 0; i--) { + status = jp->ps[i].status; + if (status != 0) + return (status); + } + return (0); +} + static void printjobcmd(struct job *jp) { @@ -377,7 +393,7 @@ showjob(struct job *jp, int mode) } #endif coredump = ""; - status = jp->ps[jp->nprocs - 1].status; + status = getjobstatus(jp); if (jp->state == 0) { statestr = "Running"; #if JOBS @@ -556,7 +572,7 @@ waitcmdloop(struct job *job) do { if (job != NULL) { if (job->state == JOBDONE) { - status = job->ps[job->nprocs - 1].status; + status = getjobstatus(job); if (WIFEXITED(status)) retval = WEXITSTATUS(status); else @@ -781,6 +797,7 @@ makejob(union node *node __unused, int nprocs) jp->nprocs = 0; jp->foreground = 0; jp->remembered = 0; + jp->pipefail = pipefailflag; #if JOBS jp->jobctl = jobctl; jp->next = NULL; @@ -1076,7 +1093,7 @@ waitforjob(struct job *jp, int *signaled) if (jp->state == JOBSTOPPED) setcurjob(jp); #endif - status = jp->ps[jp->nprocs - 1].status; + status = getjobstatus(jp); if (signaled != NULL) *signaled = WIFSIGNALED(status); /* convert to 8 bits */ diff --git a/bin/sh/options.h b/bin/sh/options.h index b3819cc2795e..500d4ad5a903 100644 --- a/bin/sh/options.h +++ b/bin/sh/options.h @@ -67,9 +67,10 @@ struct shparam { #define Pflag optval[17] #define hflag optval[18] #define nologflag optval[19] +#define pipefailflag optval[20] #define NSHORTOPTS 19 -#define NOPTS 20 +#define NOPTS 21 extern char optval[NOPTS]; extern const char optletter[NSHORTOPTS]; @@ -97,6 +98,7 @@ static const unsigned char optname[] = "\010physical" "\010trackall" "\005nolog" + "\010pipefail" ; #endif diff --git a/bin/sh/sh.1 b/bin/sh/sh.1 index ca9f4c536eb2..d1540a1f562a 100644 --- a/bin/sh/sh.1 +++ b/bin/sh/sh.1 @@ -32,7 +32,7 @@ .\" from: @(#)sh.1 8.6 (Berkeley) 5/4/95 .\" $FreeBSD$ .\" -.Dd January 24, 2019 +.Dd February 24, 2019 .Dt SH 1 .Os .Sh NAME @@ -343,6 +343,18 @@ Useful for debugging. .It Li nolog Another do-nothing option for POSIX compliance. It only has a long name. +.It Li pipefail +Change the exit status of a pipeline to the last non-zero exit status of +any command in the pipeline, if any. +Since an exit due to +.Dv SIGPIPE +counts as a non-zero exit status, +this option may cause non-zero exit status for successful pipelines +if a command such as +.Xr head 1 +in the pipeline terminates with status 0 without reading its +input completely. +This option only has a long name. .El .Pp The @@ -856,12 +868,15 @@ If the keyword .Ic !\& does not precede the pipeline, the exit status is the exit status of the last command specified -in the pipeline. +in the pipeline if the +.Cm pipefail +option is not set or all commands returned zero, +or the last non-zero exit status of any command in the pipeline otherwise. Otherwise, the exit status is the logical -NOT of the exit status of the last command. +NOT of that exit status. That is, if -the last command returns zero, the exit status is 1; if -the last command returns greater than zero, the exit status +that status is zero, the exit status is 1; if +that status is greater than zero, the exit status is zero. .Pp Because pipeline assignment of standard input or standard diff --git a/bin/sh/tests/execution/Makefile b/bin/sh/tests/execution/Makefile index a5c1cee95ddb..c8fac417de85 100644 --- a/bin/sh/tests/execution/Makefile +++ b/bin/sh/tests/execution/Makefile @@ -31,6 +31,13 @@ ${PACKAGE}FILES+= killed2.0 ${PACKAGE}FILES+= not1.0 ${PACKAGE}FILES+= not2.0 ${PACKAGE}FILES+= path1.0 +${PACKAGE}FILES+= pipefail1.0 +${PACKAGE}FILES+= pipefail2.42 +${PACKAGE}FILES+= pipefail3.42 +${PACKAGE}FILES+= pipefail4.42 +${PACKAGE}FILES+= pipefail5.42 +${PACKAGE}FILES+= pipefail6.42 +${PACKAGE}FILES+= pipefail7.0 ${PACKAGE}FILES+= redir1.0 ${PACKAGE}FILES+= redir2.0 ${PACKAGE}FILES+= redir3.0 diff --git a/bin/sh/tests/execution/pipefail1.0 b/bin/sh/tests/execution/pipefail1.0 new file mode 100644 index 000000000000..df23a012ca07 --- /dev/null +++ b/bin/sh/tests/execution/pipefail1.0 @@ -0,0 +1,4 @@ +# $FreeBSD$ + +set -o pipefail +: && : | : && : | : | : && : | : | : | : diff --git a/bin/sh/tests/execution/pipefail2.42 b/bin/sh/tests/execution/pipefail2.42 new file mode 100644 index 000000000000..b9092661c76e --- /dev/null +++ b/bin/sh/tests/execution/pipefail2.42 @@ -0,0 +1,4 @@ +# $FreeBSD$ + +set -o pipefail +(exit 42) | : diff --git a/bin/sh/tests/execution/pipefail3.42 b/bin/sh/tests/execution/pipefail3.42 new file mode 100644 index 000000000000..d96602b57f02 --- /dev/null +++ b/bin/sh/tests/execution/pipefail3.42 @@ -0,0 +1,4 @@ +# $FreeBSD$ + +set -o pipefail +: | (exit 42) diff --git a/bin/sh/tests/execution/pipefail4.42 b/bin/sh/tests/execution/pipefail4.42 new file mode 100644 index 000000000000..3399dd8c4452 --- /dev/null +++ b/bin/sh/tests/execution/pipefail4.42 @@ -0,0 +1,4 @@ +# $FreeBSD$ + +set -o pipefail +(exit 43) | (exit 42) diff --git a/bin/sh/tests/execution/pipefail5.42 b/bin/sh/tests/execution/pipefail5.42 new file mode 100644 index 000000000000..4effb2b3301e --- /dev/null +++ b/bin/sh/tests/execution/pipefail5.42 @@ -0,0 +1,5 @@ +# $FreeBSD$ + +set -o pipefail +(exit 42) | : & +wait %+ diff --git a/bin/sh/tests/execution/pipefail6.42 b/bin/sh/tests/execution/pipefail6.42 new file mode 100644 index 000000000000..7395d8c785a6 --- /dev/null +++ b/bin/sh/tests/execution/pipefail6.42 @@ -0,0 +1,6 @@ +# $FreeBSD$ + +set -o pipefail +(exit 42) | : & +set +o pipefail +wait %+ diff --git a/bin/sh/tests/execution/pipefail7.0 b/bin/sh/tests/execution/pipefail7.0 new file mode 100644 index 000000000000..797d485f3c61 --- /dev/null +++ b/bin/sh/tests/execution/pipefail7.0 @@ -0,0 +1,5 @@ +# $FreeBSD$ + +(exit 42) | : & +set -o pipefail +wait %+