From 09c5e84072326c1774bef933c8712906b0f01f85 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Tue, 20 Apr 1999 02:19:59 +0000 Subject: [PATCH] Change elog(ERROR) to get back to main loop via a plain sigsetjmp, instead of doing a kill(self, SIGQUIT) and expecting the signal handler to do it. Also, clean up inconsistent definitions of the sigjmp buffer in the several files that already referenced it. --- src/backend/bootstrap/bootstrap.c | 20 +------------------- src/backend/tcop/postgres.c | 28 +++++++++++++--------------- src/backend/utils/error/elog.c | 19 ++++--------------- src/include/tcop/tcopprot.h | 28 +++++++++++++++++++++++----- src/pl/plpgsql/src/pl_exec.c | 20 ++------------------ src/pl/tcl/pltcl.c | 20 ++------------------ 6 files changed, 45 insertions(+), 90 deletions(-) diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c index c4cb0df1c5..0c377d267c 100644 --- a/src/backend/bootstrap/bootstrap.c +++ b/src/backend/bootstrap/bootstrap.c @@ -7,7 +7,7 @@ * Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/bootstrap/bootstrap.c,v 1.57 1999/03/25 03:49:25 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/bootstrap/bootstrap.c,v 1.58 1999/04/20 02:19:53 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -184,24 +184,6 @@ static char *values[MAXATTR]; /* cooresponding attribute values */ int numattr; /* number of attributes for cur. rel */ extern bool disableFsync; /* do not fsync the database */ -/* The test for HAVE_SIGSETJMP fails on Linux 2.0.x because the test - * explicitly disallows sigsetjmp being a #define, which is how it - * is declared in Linux. So, to avoid compiler warnings about - * sigsetjmp() being redefined, let's not redefine unless necessary. - * - thomas 1997-12-27 - */ - -#if !defined(HAVE_SIGSETJMP) && !defined(sigsetjmp) -static jmp_buf Warn_restart; - -#define sigsetjmp(x,y) setjmp(x) -#define siglongjmp longjmp - -#else -static sigjmp_buf Warn_restart; - -#endif - int DebugMode; static GlobalMemory nogc = (GlobalMemory) NULL; /* special no-gc mem * context */ diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index bf04951875..231b88d620 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -7,7 +7,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.106 1999/03/22 16:45:27 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.107 1999/04/20 02:19:53 tgl Exp $ * * NOTES * this is the "main" module of the postgres backend and @@ -21,7 +21,6 @@ #include #include #include -#include #include #include #include @@ -136,15 +135,8 @@ static bool IsEmptyQuery = false; char relname[80]; /* current relation name */ -#if defined(nextstep) -jmp_buf Warn_restart; - -#define sigsetjmp(x,y) setjmp(x) -#define siglongjmp longjmp -#else +/* note: these declarations had better match tcopprot.h */ DLLIMPORT sigjmp_buf Warn_restart; - -#endif /* defined(nextstep) */ bool InError; extern int NBuffers; @@ -829,8 +821,15 @@ pg_exec_query_dest(char *query_string, /* string to execute */ /* -------------------------------- * signal handler routines used in PostgresMain() * - * handle_warn() is used to catch kill(getpid(),SIGQUIT) which - * occurs when elog(ERROR) is called. + * handle_warn() catches SIGQUIT. It forces control back to the main + * loop, just as if an internal error (elog(ERROR,...)) had occurred. + * elog() used to actually use kill(2) to induce a SIGQUIT to get here! + * But that's not 100% reliable on some systems, so now it does its own + * siglongjmp() instead. + * We still provide the signal catcher so that an error quit can be + * forced externally. This should be done only with great caution, + * however, since an asynchronous signal could leave the system in + * who-knows-what inconsistent state. * * quickdie() occurs when signalled by the postmaster. * Some backend has bought the farm, @@ -1531,7 +1530,7 @@ PostgresMain(int argc, char *argv[], int real_argc, char *real_argv[]) if (!IsUnderPostmaster) { puts("\nPOSTGRES backend interactive interface "); - puts("$Revision: 1.106 $ $Date: 1999/03/22 16:45:27 $\n"); + puts("$Revision: 1.107 $ $Date: 1999/04/20 02:19:53 $\n"); } /* ---------------- @@ -1543,8 +1542,7 @@ PostgresMain(int argc, char *argv[], int real_argc, char *real_argv[]) * so that the slaves signal the master to abort the transaction * rather than calling AbortCurrentTransaction() themselves. * - * Note: elog(ERROR) causes a kill(getpid(),SIGQUIT) to occur - * sending us back here. + * Note: elog(ERROR) does a siglongjmp() to transfer control here. * ---------------- */ diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c index 3704f457f8..e1fa74634a 100644 --- a/src/backend/utils/error/elog.c +++ b/src/backend/utils/error/elog.c @@ -7,7 +7,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/error/elog.c,v 1.40 1999/04/16 06:38:17 ishii Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/error/elog.c,v 1.41 1999/04/20 02:19:54 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -32,6 +32,7 @@ #include "miscadmin.h" #include "libpq/libpq.h" #include "storage/proc.h" +#include "tcop/tcopprot.h" #include "utils/trace.h" #ifdef USE_SYSLOG @@ -216,24 +217,12 @@ elog(int lev, const char *fmt,...) if (lev == ERROR) { - extern bool InError; - ProcReleaseSpins(NULL); /* get rid of spinlocks we hold */ if (!InError) { - if (MyProcPid == 0) { - kill(getpid(), SIGQUIT); - } else { - kill(MyProcPid, SIGQUIT); /* abort to traffic cop */ - } - pause(); + /* exit to main loop */ + siglongjmp(Warn_restart, 1); } - - /* - * The pause(3) is just to avoid race conditions where the thread - * of control on an MP system gets past here (i.e., the signal is - * not received instantaneously). - */ } if (lev == FATAL) diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h index b9f033ad72..96da4d5665 100644 --- a/src/include/tcop/tcopprot.h +++ b/src/include/tcop/tcopprot.h @@ -6,7 +6,7 @@ * * Copyright (c) 1994, Regents of the University of California * - * $Id: tcopprot.h,v 1.17 1999/02/13 23:22:13 momjian Exp $ + * $Id: tcopprot.h,v 1.18 1999/04/20 02:19:55 tgl Exp $ * * OLD COMMENTS * This file was created so that other c files could get the two @@ -18,8 +18,26 @@ #ifndef TCOPPROT_H #define TCOPPROT_H -#include -#include +#include +#include "executor/execdesc.h" +#include "parser/parse_node.h" + +/* Autoconf's test for HAVE_SIGSETJMP fails on Linux 2.0.x because the test + * explicitly disallows sigsetjmp being a #define, which is how it + * is declared in Linux. So, to avoid compiler warnings about + * sigsetjmp() being redefined, let's not redefine unless necessary. + * - thomas 1997-12-27 + * Autoconf really ought to be brighter about macro-ized system functions... + * and this code really ought to be in config.h ... + */ + +#if !defined(HAVE_SIGSETJMP) && !defined(sigsetjmp) +#define sigjmp_buf jmp_buf +#define sigsetjmp(x,y) setjmp(x) +#define siglongjmp longjmp +#endif +extern DLLIMPORT sigjmp_buf Warn_restart; +extern bool InError; #ifndef BOOTSTRAP_INCLUDE extern List *pg_parse_and_plan(char *query_string, Oid *typev, int nargs, @@ -30,7 +48,7 @@ extern void pg_exec_query_acl_override(char *query_string); extern void pg_exec_query_dest(char *query_string, CommandDest dest, bool aclOverride); -#endif /* BOOTSTRAP_HEADER */ +#endif /* BOOTSTRAP_INCLUDE */ extern void handle_warn(SIGNAL_ARGS); extern void quickdie(SIGNAL_ARGS); @@ -42,4 +60,4 @@ extern int PostgresMain(int argc, char *argv[], extern void ResetUsage(void); extern void ShowUsage(void); -#endif /* tcopprotIncluded */ +#endif /* TCOPPROT_H */ diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c index dd31dcd5f8..edb7e381a6 100644 --- a/src/pl/plpgsql/src/pl_exec.c +++ b/src/pl/plpgsql/src/pl_exec.c @@ -3,7 +3,7 @@ * procedural language * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.8 1999/03/22 16:45:30 momjian Exp $ + * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.9 1999/04/20 02:19:57 tgl Exp $ * * This software is copyrighted by Jan Wieck - Hamburg. * @@ -55,28 +55,12 @@ #include "fmgr.h" #include "access/heapam.h" +#include "tcop/tcopprot.h" #include "utils/syscache.h" #include "catalog/pg_proc.h" #include "catalog/pg_type.h" -/************************************************************ - * Make Warn_restart from tcop/postgres.c visible for us. - * The longjmp() mechanism of the elog(ERROR,...) makes it - * impossible for us to call exceptions. But at least I - * would like some suggestions about where in the PL function - * the error occured. - * - * It's ugly - Jan - ************************************************************/ -#if defined(nextstep) -#define sigjmp_buf jmp_buf -#define sigsetjmp(x,y) setjmp(x) -#define siglongjmp longjmp -#endif - -extern DLLIMPORT sigjmp_buf Warn_restart; /* in tcop/postgres.c */ - static PLpgSQL_function *error_info_func = NULL; static PLpgSQL_stmt *error_info_stmt = NULL; static char *error_info_text = NULL; diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c index c97e17558a..dc11a7111a 100644 --- a/src/pl/tcl/pltcl.c +++ b/src/pl/tcl/pltcl.c @@ -3,7 +3,7 @@ * procedural language (PL) * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/pl/tcl/pltcl.c,v 1.8 1998/11/27 20:05:27 vadim Exp $ + * $Header: /cvsroot/pgsql/src/pl/tcl/pltcl.c,v 1.9 1999/04/20 02:19:59 tgl Exp $ * * This software is copyrighted by Jan Wieck - Hamburg. * @@ -52,6 +52,7 @@ #include "fmgr.h" #include "access/heapam.h" +#include "tcop/tcopprot.h" #include "utils/syscache.h" #include "catalog/pg_proc.h" #include "catalog/pg_type.h" @@ -90,23 +91,6 @@ typedef struct pltcl_query_desc } pltcl_query_desc; -/************************************************************ - * Make Warn_restart from tcop/postgres.c visible for us. - * The longjmp() mechanism of the elog(ERROR,...) restart let's - * interpreter levels lay around. So we must tidy up in that - * case and thus, we have to catch the longjmp's sometimes to - * return though all the interpreter levels back. - * - * It's ugly - Jan - ************************************************************/ -#if defined(nextstep) -#define sigjmp_buf jmp_buf -#define sigsetjmp(x,y) setjmp(x) -#define siglongjmp longjmp -#endif - -extern sigjmp_buf Warn_restart; /* in tcop/postgres.c */ - /********************************************************************** * Global data **********************************************************************/ -- 2.40.0