Over in
https://www.postgresql.org/message-id/eaf326ad693e74eba068f33a7f518...@oss.nttdata.com
Justin
Pryzby suggested that psql might need the ability to capture the shell exit
code.
This is a POC patch that does that, but doesn't touch on the ON_ERROR_STOP
stuff.
I've added some very rudimentary tests, but haven't touched the
documentation, because I strongly suspect that someone will suggest a
better name for the variable.
But basically, it works like this
-- SHELL_EXIT_CODE is undefined
\echo :SHELL_EXIT_CODE
:SHELL_EXIT_CODE
-- bad \!
\! borp
sh: line 1: borp: command not found
\echo :SHELL_EXIT_CODE
32512
-- bad backtick
\set var `borp`
sh: line 1: borp: command not found
\echo :SHELL_EXIT_CODE
127
-- good \!
\! true
\echo :SHELL_EXIT_CODE
0
-- play with exit codes
\! exit 4
\echo :SHELL_EXIT_CODE
1024
\set var `exit 3`
\echo :SHELL_EXIT_CODE
3
Feedback welcome.
From 119837575f4d0da804d92ec797bbf11e8075e595 Mon Sep 17 00:00:00 2001
From: coreyhuinker <corey.huin...@gmail.com>
Date: Fri, 4 Nov 2022 04:45:39 -0400
Subject: [PATCH] POC: expose shell exit code as a psql variable
---
src/bin/psql/command.c | 4 ++++
src/bin/psql/help.c | 2 ++
src/bin/psql/psqlscanslash.l | 28 +++++++++++++++++++++++++---
src/test/regress/expected/psql.out | 11 +++++++++++
src/test/regress/sql/psql.sql | 7 +++++++
5 files changed, 49 insertions(+), 3 deletions(-)
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index ab613dd49e..4666a63051 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -4957,6 +4957,7 @@ static bool
do_shell(const char *command)
{
int result;
+ char exit_code_buf[32];
fflush(NULL);
if (!command)
@@ -4984,6 +4985,9 @@ do_shell(const char *command)
else
result = system(command);
+ snprintf(exit_code_buf, sizeof(exit_code_buf), "%d", WEXITSTATUS(result));
+ SetVariable(pset.vars, "SHELL_EXIT_CODE", exit_code_buf);
+
if (result == 127 || result == -1)
{
pg_log_error("\\!: failed");
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index f8ce1a0706..04f996332e 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -454,6 +454,8 @@ helpVariables(unsigned short int pager)
" show all results of a combined query (\\;) instead of only the last\n");
HELP0(" SHOW_CONTEXT\n"
" controls display of message context fields [never, errors, always]\n");
+ HELP0(" SHELL_EXIT_CODE\n"
+ " Exit code of the last shell command\n");
HELP0(" SINGLELINE\n"
" if set, end of line terminates SQL commands (same as -S option)\n");
HELP0(" SINGLESTEP\n"
diff --git a/src/bin/psql/psqlscanslash.l b/src/bin/psql/psqlscanslash.l
index a467b72144..30e6f5dcd4 100644
--- a/src/bin/psql/psqlscanslash.l
+++ b/src/bin/psql/psqlscanslash.l
@@ -27,6 +27,8 @@
%{
#include "fe_utils/psqlscan_int.h"
+#include "settings.h"
+#include "variables.h"
/*
* We must have a typedef YYSTYPE for yylex's first argument, but this lexer
@@ -774,6 +776,8 @@ evaluate_backtick(PsqlScanState state)
bool error = false;
char buf[512];
size_t result;
+ int exit_code = 0;
+ char exit_code_buf[32];
initPQExpBuffer(&cmd_output);
@@ -783,6 +787,7 @@ evaluate_backtick(PsqlScanState state)
{
pg_log_error("%s: %m", cmd);
error = true;
+ exit_code = -1;
}
if (!error)
@@ -800,10 +805,25 @@ evaluate_backtick(PsqlScanState state)
} while (!feof(fd));
}
- if (fd && pclose(fd) == -1)
+ if (fd)
{
- pg_log_error("%s: %m", cmd);
- error = true;
+ exit_code = pclose(fd);
+ if (exit_code == -1)
+ {
+ pg_log_error("%s: %m", cmd);
+ error = true;
+ }
+ if (WIFEXITED(exit_code))
+ {
+ exit_code=WEXITSTATUS(exit_code);
+ }
+ else if(WIFSIGNALED(exit_code)) {
+ exit_code=WTERMSIG(exit_code);
+ }
+ else if(WIFSTOPPED(exit_code)) {
+ //If you need to act upon the process stopping, do it here.
+ exit_code=WSTOPSIG(exit_code);
+ }
}
if (PQExpBufferDataBroken(cmd_output))
@@ -826,5 +846,7 @@ evaluate_backtick(PsqlScanState state)
appendBinaryPQExpBuffer(output_buf, cmd_output.data, cmd_output.len);
}
+ snprintf(exit_code_buf, sizeof(exit_code_buf), "%d", exit_code);
+ SetVariable(pset.vars, "SHELL_EXIT_CODE", exit_code_buf);
termPQExpBuffer(&cmd_output);
}
diff --git a/src/test/regress/expected/psql.out b/src/test/regress/expected/psql.out
index a7f5700edc..33202ffda7 100644
--- a/src/test/regress/expected/psql.out
+++ b/src/test/regress/expected/psql.out
@@ -1275,6 +1275,17 @@ execute q;
+----+-------------+
deallocate q;
+-- test SHELL_EXIT_CODE
+\! nosuchcommand
+sh: line 1: nosuchcommand: command not found
+\echo :SHELL_EXIT_CODE
+127
+\set nosuchvar `nosuchcommand`
+sh: line 1: nosuchcommand: command not found
+\! nosuchcommand
+sh: line 1: nosuchcommand: command not found
+\echo :SHELL_EXIT_CODE
+127
-- test single-line header and data
prepare q as select repeat('x',2*n) as "0123456789abcdef", repeat('y',20-2*n) as "0123456789" from generate_series(1,10) as n;
\pset linestyle ascii
diff --git a/src/test/regress/sql/psql.sql b/src/test/regress/sql/psql.sql
index 1149c6a839..99b874d5a9 100644
--- a/src/test/regress/sql/psql.sql
+++ b/src/test/regress/sql/psql.sql
@@ -277,6 +277,13 @@ execute q;
deallocate q;
+-- test SHELL_EXIT_CODE
+\! nosuchcommand
+\echo :SHELL_EXIT_CODE
+\set nosuchvar `nosuchcommand`
+\! nosuchcommand
+\echo :SHELL_EXIT_CODE
+
-- test single-line header and data
prepare q as select repeat('x',2*n) as "0123456789abcdef", repeat('y',20-2*n) as "0123456789" from generate_series(1,10) as n;
--
2.38.1
