> > If I were trying to solve Andreas' problem, I'd pipe stderr 
> > to some program that stores recent log output in a file that 
> > I know the location of and can read from the hypothetical 
> > log-grabber function.  Actually I don't see that there's any 
> > need to involve Postgres itself in this issue at all --- 
> > seems like the only agreement needed is between the GUI and 
> > the postmaster launching script about where the log file is.
> 
> Thanks Tom. I wonder if we (the pgAdmin team) finally need to bite the
> proverbial bullet and write a helper daemon that can allow access to
> logs as well as config files and pg_ctl etc. as an optional extra
> component.

It would certainly make things a lot easier for the box admin if you did
this as extension functions in pg instead of a separate daemon (even if
these are not installed in pg by default, but have to be installed
manually. Better if they are included by default, of course, from the
easy-to-admin perspective). Then it's just one set of firewall rules,
one process to check if it's running, etc.



Specifically about the logs, I still think there is a lot of value to
being able to read the logs remotely even if you can't restart
postmaster. Looking at the server logs can help you debug the database
client (for example when the app won't give you the full error msg, but
it goes in the server log). It won't help you if it's a postmaster
problem (since you won't get to it), but there are a lot of other
situations where it will.
(This is, btw, how MSSQL does it at least - you can view the server log
remotely if the server starts. If not, you'll have to go to the log
viewer on the server)


//Magnus


Mon, 7 Jun 2004 18:01:19 +0200
"Magnus Hagander" <mha@sollentuna.net>
Re: serverlog function (log_destination file) 
Magnus Hagander wrote:

>Specifically about the logs, I still think there is a lot of value to
>being able to read the logs remotely even if you can't restart
>postmaster.
>
Since I believe that retrieving the logs easily without server file 
access is a feature that's welcomed by many users, here's my proposal.

The attached diff will
- add a guc-variable log_filename
- extend log_destination to accept the keyword 'file'
- elog to that file if configured
- provide two functions pg_logfile_length() and pg_logfile to obtain the 
contents.

int4 pg_logfile_length()
cstring pg_logfile(int4 size, int4 position)
size (may be null meaning max) is the chunk size (max: currently 50000)
position (may be null meaning -size) is the start position; positive 
counting from log file start, negative from end.


Regards,
Andreas
Tue, 08 Jun 2004 20:27:29 +0200
Andreas Pflug <pgadmin@pse-consulting.de>
Re: serverlog function (log_destination file)

Looks good to me.  The only issue I saw was that the default file name
mentioned in postgresql.conf doesn't match the actual default.

Is this ready to be added to the patch queue?

---------------------------------------------------------------------------

Andreas Pflug wrote:
> Magnus Hagander wrote:
> 
> >Specifically about the logs, I still think there is a lot of value to
> >being able to read the logs remotely even if you can't restart
> >postmaster.
> >
> Since I believe that retrieving the logs easily without server file 
> access is a feature that's welcomed by many users, here's my proposal.
> 
> The attached diff will
> - add a guc-variable log_filename
> - extend log_destination to accept the keyword 'file'
> - elog to that file if configured
> - provide two functions pg_logfile_length() and pg_logfile to obtain the 
> contents.
> 
> int4 pg_logfile_length()
> cstring pg_logfile(int4 size, int4 position)
> size (may be null meaning max) is the chunk size (max: currently 50000)
> position (may be null meaning -size) is the start position; positive 
> counting from log file start, negative from end.
> 
> 
> Regards,
> Andreas
> 

> Index: backend/postmaster/postmaster.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/postmaster/postmaster.c,v
> retrieving revision 1.402
> diff -u -r1.402 postmaster.c
> --- backend/postmaster/postmaster.c	3 Jun 2004 02:08:03 -0000	1.402
> +++ backend/postmaster/postmaster.c	8 Jun 2004 18:07:30 -0000
> @@ -532,6 +532,9 @@
>  	/* If timezone is not set, determine what the OS uses */
>  	pg_timezone_initialize();
> 
> +    /* open alternate logfile, if any */
> +	LogFileOpen();
> +
>  #ifdef EXEC_BACKEND
>  	write_nondefault_variables(PGC_POSTMASTER);
>  #endif
> Index: backend/storage/ipc/ipc.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/storage/ipc/ipc.c,v
> retrieving revision 1.87
> diff -u -r1.87 ipc.c
> --- backend/storage/ipc/ipc.c	12 Dec 2003 18:45:09 -0000	1.87
> +++ backend/storage/ipc/ipc.c	8 Jun 2004 18:07:31 -0000
> @@ -111,6 +111,8 @@
>  							  on_proc_exit_list[on_proc_exit_index].arg);
> 
>  	elog(DEBUG3, "exit(%d)", code);
> +
> +	LogFileClose();
>  	exit(code);
>  }
> 
> Index: backend/utils/adt/misc.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/adt/misc.c,v
> retrieving revision 1.34
> diff -u -r1.34 misc.c
> --- backend/utils/adt/misc.c	2 Jun 2004 21:29:29 -0000	1.34
> +++ backend/utils/adt/misc.c	8 Jun 2004 18:07:36 -0000
> @@ -103,3 +103,64 @@
>  {
>  	PG_RETURN_INT32(pg_signal_backend(PG_GETARG_INT32(0),SIGINT));
>  }
> +
> +Datum pg_logfile_length(PG_FUNCTION_ARGS)
> +{
> +	extern FILE *logfile; // in elog.c
> +
> +	if (logfile)
> +		PG_RETURN_INT32(ftell(logfile));
> +	PG_RETURN_INT32(0);
> +}
> +
> +
> +#define MAXLOGFILECHUNK 50000
> +Datum pg_logfile(PG_FUNCTION_ARGS)
> +{
> +	size_t size=MAXLOGFILECHUNK;
> +	char *buf=0;
> +	size_t nbytes;
> +
> +	char *filename = LogFileName();
> +	if (filename)
> +	{
> +		if (!PG_ARGISNULL(0))
> +			size = PG_GETARG_INT32(0);
> +		if (size > MAXLOGFILECHUNK)
> +		{
> +			size = MAXLOGFILECHUNK;
> +			ereport(WARNING,
> +					(errcode(ERRCODE_OUT_OF_MEMORY),
> +					 errmsg("Maximum size is %d.", MAXLOGFILECHUNK)));
> +		}
> +
> +		FILE *f=fopen(filename, "r");
> +		if (f)
> +		{
> +			if (PG_ARGISNULL(1))
> +				fseek(f, -size, SEEK_END);
> +			else
> +			{
> +				long pos = PG_GETARG_INT32(1);
> +				if (pos >= 0)
> +					fseek(f, pos, SEEK_SET);
> +				else
> +					fseek(f, pos, SEEK_END);
> +			}
> +			buf = palloc(size+1);
> +			nbytes = fread(buf, 1, size, f);
> +			buf[nbytes] = 0;
> +
> +			fclose(f);
> +		}
> +		else
> +		{
> +			ereport(WARNING,
> +					(errcode(ERRCODE_NO_DATA),
> +					 errmsg("Could not open log file %s.", filename)));
> +		}
> +		free(filename);
> +	}
> +
> +	PG_RETURN_CSTRING(buf);
> +}
> Index: backend/utils/error/elog.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/error/elog.c,v
> retrieving revision 1.140
> diff -u -r1.140 elog.c
> --- backend/utils/error/elog.c	3 Jun 2004 02:08:04 -0000	1.140
> +++ backend/utils/error/elog.c	8 Jun 2004 18:07:39 -0000
> @@ -71,8 +71,10 @@
>  PGErrorVerbosity Log_error_verbosity = PGERROR_VERBOSE;
>  char       *Log_line_prefix = NULL; /* format for extra log line info */
>  unsigned int Log_destination = LOG_DESTINATION_STDERR;
> +char *Log_filename = NULL;
> 
>  bool in_fatal_exit = false;
> +FILE *logfile = NULL;
> 
>  #ifdef HAVE_SYSLOG
>  char	   *Syslog_facility;	/* openlog() parameters */
> @@ -936,6 +938,69 @@
> 
> 
>  /*
> + * Name of configured log file, or NULL
> + * must be freed after usage
> + */
> +char*
> +LogFileName(void)
> +{
> +	if (Log_filename && (Log_destination & LOG_DESTINATION_FILE))
> +	{
> +		if (is_absolute_path(Log_filename))
> +			return strdup(Log_filename);
> +		else
> +		{
> +			char *buf = malloc(strlen(DataDir) + strlen(Log_filename) +2);
> +			if (!buf)
> +				ereport(FATAL,
> +						(errcode(ERRCODE_OUT_OF_MEMORY),
> +						 errmsg("out of memory")));
> +
> +			sprintf(buf, "%s/%s", DataDir, Log_filename);
> +
> +			return buf;
> +		}
> +	}
> +	return NULL;
> +}
> +
> +
> +/*
> + * Open log file, if configured.
> + */
> +void
> +LogFileOpen(void)
> +{
> +	char *filename = LogFileName();
> +
> +	if (filename)
> +	{
> +		LogFileClose();
> +
> +		logfile = fopen(filename, "at");
> +
> +		if (!logfile)
> +			ereport(WARNING,
> +					(errcode(ERRCODE_CONFIG_FILE_ERROR),
> +					 errmsg("could not open log file %s", filename)));
> +
> +		free(filename);
> +	}
> +}
> +
> +
> +/*
> + * Close log file, if open.
> + */
> +void
> +LogFileClose(void)
> +{
> +	if (logfile)
> +		fclose(logfile);
> +	logfile = NULL;
> +}
> +
> +/*
>   * Initialization of error output file
>   */
>  void
> @@ -1445,6 +1510,11 @@
>  	if ((Log_destination & LOG_DESTINATION_STDERR) || whereToSendOutput == Debug)
>  	{
>  		fprintf(stderr, "%s", buf.data);
> +	}
> +
> +	if (logfile && (Log_destination & LOG_DESTINATION_FILE))
> +	{
> +		fprintf(logfile, "%s", buf.data);
>  	}
> 
>  	pfree(buf.data);
> Index: backend/utils/misc/guc.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/misc/guc.c,v
> retrieving revision 1.210
> diff -u -r1.210 guc.c
> --- backend/utils/misc/guc.c	30 May 2004 23:40:38 -0000	1.210
> +++ backend/utils/misc/guc.c	8 Jun 2004 18:07:47 -0000
> @@ -76,6 +76,8 @@
>  static const char *assign_log_destination(const char *value,
>  				bool doit, GucSource source);
>  
> +extern char *Log_filename;
> +
>  #ifdef HAVE_SYSLOG
>  extern char *Syslog_facility;
>  extern char *Syslog_ident;
> @@ -1644,13 +1646,23 @@
>  	{
>  		{"log_destination", PGC_POSTMASTER, LOGGING_WHERE,
>  		 gettext_noop("Sets the target for log output."),
> -		 gettext_noop("Valid values are combinations of stderr, syslog "
> +		 gettext_noop("Valid values are combinations of stderr, file, syslog "
>  					  "and eventlog, depending on platform."),
>  		 GUC_LIST_INPUT | GUC_REPORT
>  		},
>  		&log_destination_string,
>  		"stderr", assign_log_destination, NULL
>  	},
> +	{
> +		{"log_filename", PGC_POSTMASTER, LOGGING_WHERE,
> +		 gettext_noop("Sets the target filename for log output."),
> +		 gettext_noop("May be specified as relative to the cluster directory "
> +					  "or as absolute path."),
> +		 GUC_LIST_INPUT | GUC_REPORT
> +		},
> +		&Log_filename,
> +		"postgresql.log", NULL, NULL
> +	},
>  
>  #ifdef HAVE_SYSLOG
>  	{
> @@ -4775,6 +4787,8 @@
>  	
>  		if (pg_strcasecmp(tok,"stderr") == 0)
>  			newlogdest |= LOG_DESTINATION_STDERR;
> +		else if (pg_strcasecmp(tok,"file") == 0)
> +			newlogdest |= LOG_DESTINATION_FILE;
>  #ifdef HAVE_SYSLOG
>  		else if (pg_strcasecmp(tok,"syslog") == 0)
>  			newlogdest |= LOG_DESTINATION_SYSLOG;
> Index: backend/utils/misc/postgresql.conf.sample
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/misc/postgresql.conf.sample,v
> retrieving revision 1.113
> diff -u -r1.113 postgresql.conf.sample
> --- backend/utils/misc/postgresql.conf.sample	7 Apr 2004 05:05:50 -0000	1.113
> +++ backend/utils/misc/postgresql.conf.sample	8 Jun 2004 18:07:48 -0000
> @@ -147,9 +147,10 @@
>  
>  # - Where to Log -
>  
> -#log_destination = 'stderr'	# Valid values are combinations of stderr,
> +#log_destination = 'stderr'	# Valid values are combinations of stderr, file,
>                                  # syslog and eventlog, depending on
>                                  # platform.
> +#log_filename = 'pgsql.log'
>  #syslog_facility = 'LOCAL0'
>  #syslog_ident = 'postgres'
>  
> Index: include/catalog/pg_proc.h
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/include/catalog/pg_proc.h,v
> retrieving revision 1.334
> diff -u -r1.334 pg_proc.h
> --- include/catalog/pg_proc.h	2 Jun 2004 21:29:29 -0000	1.334
> +++ include/catalog/pg_proc.h	8 Jun 2004 18:08:03 -0000
> @@ -3588,6 +3588,12 @@
>  DATA(insert OID = 2243 ( bit_or						   PGNSP PGUID 12 t f f f i 1 1560 "1560" _null_ aggregate_dummy - _null_));
>  DESCR("bitwise-or bit aggregate");
> 
> +DATA(insert OID = 2550(  pg_logfile_length		       PGNSP PGUID 12 f f f f v 0 23 "" _null_ pg_logfile_length - _null_ ));
> +DESCR("length of log file");
> +DATA(insert OID = 2551(  pg_logfile		               PGNSP PGUID 12 f f f f v 2 2275 "23 23" _null_ pg_logfile - _null_ ));
> +DESCR("return log file contents");
> +
> +
>  /*
>   * Symbolic values for provolatile column: these indicate whether the result
>   * of a function is dependent *only* on the values of its explicit arguments,
> Index: include/utils/builtins.h
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/include/utils/builtins.h,v
> retrieving revision 1.241
> diff -u -r1.241 builtins.h
> --- include/utils/builtins.h	2 Jun 2004 21:29:29 -0000	1.241
> +++ include/utils/builtins.h	8 Jun 2004 18:08:05 -0000
> @@ -356,6 +356,8 @@
>  extern Datum current_database(PG_FUNCTION_ARGS);
>  extern Datum pg_terminate_backend(PG_FUNCTION_ARGS);
>  extern Datum pg_cancel_backend(PG_FUNCTION_ARGS);
> +extern Datum pg_logfile_length(PG_FUNCTION_ARGS);
> +extern Datum pg_logfile(PG_FUNCTION_ARGS);
> 
>  /* not_in.c */
>  extern Datum int4notin(PG_FUNCTION_ARGS);
> Index: include/utils/elog.h
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/include/utils/elog.h,v
> retrieving revision 1.68
> diff -u -r1.68 elog.h
> --- include/utils/elog.h	5 Apr 2004 03:02:10 -0000	1.68
> +++ include/utils/elog.h	8 Jun 2004 18:08:06 -0000
> @@ -182,8 +182,12 @@
>  #define LOG_DESTINATION_STDERR   1
>  #define LOG_DESTINATION_SYSLOG   2
>  #define LOG_DESTINATION_EVENTLOG 4
> +#define LOG_DESTINATION_FILE     8
> 
>  /* Other exported functions */
>  extern void DebugFileOpen(void);
> +extern char *LogFileName(void);
> +extern void LogFileOpen(void);
> +extern void LogFileClose(void);
> 
>  #endif   /* ELOG_H */

> 
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 10 Jun 2004 00:10:38 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)

Oh, it would need doc additions. I can do that when I apply, or you can
resubmit.


---------------------------------------------------------------------------

Andreas Pflug wrote:
> Magnus Hagander wrote:
> 
> >Specifically about the logs, I still think there is a lot of value to
> >being able to read the logs remotely even if you can't restart
> >postmaster.
> >
> Since I believe that retrieving the logs easily without server file 
> access is a feature that's welcomed by many users, here's my proposal.
> 
> The attached diff will
> - add a guc-variable log_filename
> - extend log_destination to accept the keyword 'file'
> - elog to that file if configured
> - provide two functions pg_logfile_length() and pg_logfile to obtain the 
> contents.
> 
> int4 pg_logfile_length()
> cstring pg_logfile(int4 size, int4 position)
> size (may be null meaning max) is the chunk size (max: currently 50000)
> position (may be null meaning -size) is the start position; positive 
> counting from log file start, negative from end.
> 
> 
> Regards,
> Andreas
> 

> Index: backend/postmaster/postmaster.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/postmaster/postmaster.c,v
> retrieving revision 1.402
> diff -u -r1.402 postmaster.c
> --- backend/postmaster/postmaster.c	3 Jun 2004 02:08:03 -0000	1.402
> +++ backend/postmaster/postmaster.c	8 Jun 2004 18:07:30 -0000
> @@ -532,6 +532,9 @@
>  	/* If timezone is not set, determine what the OS uses */
>  	pg_timezone_initialize();
> 
> +    /* open alternate logfile, if any */
> +	LogFileOpen();
> +
>  #ifdef EXEC_BACKEND
>  	write_nondefault_variables(PGC_POSTMASTER);
>  #endif
> Index: backend/storage/ipc/ipc.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/storage/ipc/ipc.c,v
> retrieving revision 1.87
> diff -u -r1.87 ipc.c
> --- backend/storage/ipc/ipc.c	12 Dec 2003 18:45:09 -0000	1.87
> +++ backend/storage/ipc/ipc.c	8 Jun 2004 18:07:31 -0000
> @@ -111,6 +111,8 @@
>  							  on_proc_exit_list[on_proc_exit_index].arg);
> 
>  	elog(DEBUG3, "exit(%d)", code);
> +
> +	LogFileClose();
>  	exit(code);
>  }
> 
> Index: backend/utils/adt/misc.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/adt/misc.c,v
> retrieving revision 1.34
> diff -u -r1.34 misc.c
> --- backend/utils/adt/misc.c	2 Jun 2004 21:29:29 -0000	1.34
> +++ backend/utils/adt/misc.c	8 Jun 2004 18:07:36 -0000
> @@ -103,3 +103,64 @@
>  {
>  	PG_RETURN_INT32(pg_signal_backend(PG_GETARG_INT32(0),SIGINT));
>  }
> +
> +Datum pg_logfile_length(PG_FUNCTION_ARGS)
> +{
> +	extern FILE *logfile; // in elog.c
> +
> +	if (logfile)
> +		PG_RETURN_INT32(ftell(logfile));
> +	PG_RETURN_INT32(0);
> +}
> +
> +
> +#define MAXLOGFILECHUNK 50000
> +Datum pg_logfile(PG_FUNCTION_ARGS)
> +{
> +	size_t size=MAXLOGFILECHUNK;
> +	char *buf=0;
> +	size_t nbytes;
> +
> +	char *filename = LogFileName();
> +	if (filename)
> +	{
> +		if (!PG_ARGISNULL(0))
> +			size = PG_GETARG_INT32(0);
> +		if (size > MAXLOGFILECHUNK)
> +		{
> +			size = MAXLOGFILECHUNK;
> +			ereport(WARNING,
> +					(errcode(ERRCODE_OUT_OF_MEMORY),
> +					 errmsg("Maximum size is %d.", MAXLOGFILECHUNK)));
> +		}
> +
> +		FILE *f=fopen(filename, "r");
> +		if (f)
> +		{
> +			if (PG_ARGISNULL(1))
> +				fseek(f, -size, SEEK_END);
> +			else
> +			{
> +				long pos = PG_GETARG_INT32(1);
> +				if (pos >= 0)
> +					fseek(f, pos, SEEK_SET);
> +				else
> +					fseek(f, pos, SEEK_END);
> +			}
> +			buf = palloc(size+1);
> +			nbytes = fread(buf, 1, size, f);
> +			buf[nbytes] = 0;
> +
> +			fclose(f);
> +		}
> +		else
> +		{
> +			ereport(WARNING,
> +					(errcode(ERRCODE_NO_DATA),
> +					 errmsg("Could not open log file %s.", filename)));
> +		}
> +		free(filename);
> +	}
> +
> +	PG_RETURN_CSTRING(buf);
> +}
> Index: backend/utils/error/elog.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/error/elog.c,v
> retrieving revision 1.140
> diff -u -r1.140 elog.c
> --- backend/utils/error/elog.c	3 Jun 2004 02:08:04 -0000	1.140
> +++ backend/utils/error/elog.c	8 Jun 2004 18:07:39 -0000
> @@ -71,8 +71,10 @@
>  PGErrorVerbosity Log_error_verbosity = PGERROR_VERBOSE;
>  char       *Log_line_prefix = NULL; /* format for extra log line info */
>  unsigned int Log_destination = LOG_DESTINATION_STDERR;
> +char *Log_filename = NULL;
> 
>  bool in_fatal_exit = false;
> +FILE *logfile = NULL;
> 
>  #ifdef HAVE_SYSLOG
>  char	   *Syslog_facility;	/* openlog() parameters */
> @@ -936,6 +938,69 @@
> 
> 
>  /*
> + * Name of configured log file, or NULL
> + * must be freed after usage
> + */
> +char*
> +LogFileName(void)
> +{
> +	if (Log_filename && (Log_destination & LOG_DESTINATION_FILE))
> +	{
> +		if (is_absolute_path(Log_filename))
> +			return strdup(Log_filename);
> +		else
> +		{
> +			char *buf = malloc(strlen(DataDir) + strlen(Log_filename) +2);
> +			if (!buf)
> +				ereport(FATAL,
> +						(errcode(ERRCODE_OUT_OF_MEMORY),
> +						 errmsg("out of memory")));
> +
> +			sprintf(buf, "%s/%s", DataDir, Log_filename);
> +
> +			return buf;
> +		}
> +	}
> +	return NULL;
> +}
> +
> +
> +/*
> + * Open log file, if configured.
> + */
> +void
> +LogFileOpen(void)
> +{
> +	char *filename = LogFileName();
> +
> +	if (filename)
> +	{
> +		LogFileClose();
> +
> +		logfile = fopen(filename, "at");
> +
> +		if (!logfile)
> +			ereport(WARNING,
> +					(errcode(ERRCODE_CONFIG_FILE_ERROR),
> +					 errmsg("could not open log file %s", filename)));
> +
> +		free(filename);
> +	}
> +}
> +
> +
> +/*
> + * Close log file, if open.
> + */
> +void
> +LogFileClose(void)
> +{
> +	if (logfile)
> +		fclose(logfile);
> +	logfile = NULL;
> +}
> +
> +/*
>   * Initialization of error output file
>   */
>  void
> @@ -1445,6 +1510,11 @@
>  	if ((Log_destination & LOG_DESTINATION_STDERR) || whereToSendOutput == Debug)
>  	{
>  		fprintf(stderr, "%s", buf.data);
> +	}
> +
> +	if (logfile && (Log_destination & LOG_DESTINATION_FILE))
> +	{
> +		fprintf(logfile, "%s", buf.data);
>  	}
> 
>  	pfree(buf.data);
> Index: backend/utils/misc/guc.c
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/misc/guc.c,v
> retrieving revision 1.210
> diff -u -r1.210 guc.c
> --- backend/utils/misc/guc.c	30 May 2004 23:40:38 -0000	1.210
> +++ backend/utils/misc/guc.c	8 Jun 2004 18:07:47 -0000
> @@ -76,6 +76,8 @@
>  static const char *assign_log_destination(const char *value,
>  				bool doit, GucSource source);
>  
> +extern char *Log_filename;
> +
>  #ifdef HAVE_SYSLOG
>  extern char *Syslog_facility;
>  extern char *Syslog_ident;
> @@ -1644,13 +1646,23 @@
>  	{
>  		{"log_destination", PGC_POSTMASTER, LOGGING_WHERE,
>  		 gettext_noop("Sets the target for log output."),
> -		 gettext_noop("Valid values are combinations of stderr, syslog "
> +		 gettext_noop("Valid values are combinations of stderr, file, syslog "
>  					  "and eventlog, depending on platform."),
>  		 GUC_LIST_INPUT | GUC_REPORT
>  		},
>  		&log_destination_string,
>  		"stderr", assign_log_destination, NULL
>  	},
> +	{
> +		{"log_filename", PGC_POSTMASTER, LOGGING_WHERE,
> +		 gettext_noop("Sets the target filename for log output."),
> +		 gettext_noop("May be specified as relative to the cluster directory "
> +					  "or as absolute path."),
> +		 GUC_LIST_INPUT | GUC_REPORT
> +		},
> +		&Log_filename,
> +		"postgresql.log", NULL, NULL
> +	},
>  
>  #ifdef HAVE_SYSLOG
>  	{
> @@ -4775,6 +4787,8 @@
>  	
>  		if (pg_strcasecmp(tok,"stderr") == 0)
>  			newlogdest |= LOG_DESTINATION_STDERR;
> +		else if (pg_strcasecmp(tok,"file") == 0)
> +			newlogdest |= LOG_DESTINATION_FILE;
>  #ifdef HAVE_SYSLOG
>  		else if (pg_strcasecmp(tok,"syslog") == 0)
>  			newlogdest |= LOG_DESTINATION_SYSLOG;
> Index: backend/utils/misc/postgresql.conf.sample
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/backend/utils/misc/postgresql.conf.sample,v
> retrieving revision 1.113
> diff -u -r1.113 postgresql.conf.sample
> --- backend/utils/misc/postgresql.conf.sample	7 Apr 2004 05:05:50 -0000	1.113
> +++ backend/utils/misc/postgresql.conf.sample	8 Jun 2004 18:07:48 -0000
> @@ -147,9 +147,10 @@
>  
>  # - Where to Log -
>  
> -#log_destination = 'stderr'	# Valid values are combinations of stderr,
> +#log_destination = 'stderr'	# Valid values are combinations of stderr, file,
>                                  # syslog and eventlog, depending on
>                                  # platform.
> +#log_filename = 'pgsql.log'
>  #syslog_facility = 'LOCAL0'
>  #syslog_ident = 'postgres'
>  
> Index: include/catalog/pg_proc.h
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/include/catalog/pg_proc.h,v
> retrieving revision 1.334
> diff -u -r1.334 pg_proc.h
> --- include/catalog/pg_proc.h	2 Jun 2004 21:29:29 -0000	1.334
> +++ include/catalog/pg_proc.h	8 Jun 2004 18:08:03 -0000
> @@ -3588,6 +3588,12 @@
>  DATA(insert OID = 2243 ( bit_or						   PGNSP PGUID 12 t f f f i 1 1560 "1560" _null_ aggregate_dummy - _null_));
>  DESCR("bitwise-or bit aggregate");
> 
> +DATA(insert OID = 2550(  pg_logfile_length		       PGNSP PGUID 12 f f f f v 0 23 "" _null_ pg_logfile_length - _null_ ));
> +DESCR("length of log file");
> +DATA(insert OID = 2551(  pg_logfile		               PGNSP PGUID 12 f f f f v 2 2275 "23 23" _null_ pg_logfile - _null_ ));
> +DESCR("return log file contents");
> +
> +
>  /*
>   * Symbolic values for provolatile column: these indicate whether the result
>   * of a function is dependent *only* on the values of its explicit arguments,
> Index: include/utils/builtins.h
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/include/utils/builtins.h,v
> retrieving revision 1.241
> diff -u -r1.241 builtins.h
> --- include/utils/builtins.h	2 Jun 2004 21:29:29 -0000	1.241
> +++ include/utils/builtins.h	8 Jun 2004 18:08:05 -0000
> @@ -356,6 +356,8 @@
>  extern Datum current_database(PG_FUNCTION_ARGS);
>  extern Datum pg_terminate_backend(PG_FUNCTION_ARGS);
>  extern Datum pg_cancel_backend(PG_FUNCTION_ARGS);
> +extern Datum pg_logfile_length(PG_FUNCTION_ARGS);
> +extern Datum pg_logfile(PG_FUNCTION_ARGS);
> 
>  /* not_in.c */
>  extern Datum int4notin(PG_FUNCTION_ARGS);
> Index: include/utils/elog.h
> ===================================================================
> RCS file: /projects/cvsroot/pgsql-server/src/include/utils/elog.h,v
> retrieving revision 1.68
> diff -u -r1.68 elog.h
> --- include/utils/elog.h	5 Apr 2004 03:02:10 -0000	1.68
> +++ include/utils/elog.h	8 Jun 2004 18:08:06 -0000
> @@ -182,8 +182,12 @@
>  #define LOG_DESTINATION_STDERR   1
>  #define LOG_DESTINATION_SYSLOG   2
>  #define LOG_DESTINATION_EVENTLOG 4
> +#define LOG_DESTINATION_FILE     8
> 
>  /* Other exported functions */
>  extern void DebugFileOpen(void);
> +extern char *LogFileName(void);
> +extern void LogFileOpen(void);
> +extern void LogFileClose(void);
> 
>  #endif   /* ELOG_H */

> 
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 10 Jun 2004 00:11:09 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)
Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Looks good to me.  The only issue I saw was that the default file name
> mentioned in postgresql.conf doesn't match the actual default.

I'm really not happy with the concept that the postmaster overrides
its stderr direction.

			regards, tom lane

Thu, 10 Jun 2004 01:14:01 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: [PATCHES] serverlog function (log_destination file) 


Tom Lane wrote:

>Bruce Momjian <pgman@candle.pha.pa.us> writes:
>  
>
>>Looks good to me.  The only issue I saw was that the default file name
>>mentioned in postgresql.conf doesn't match the actual default.
>>    
>>
>
>I'm really not happy with the concept that the postmaster overrides
>its stderr direction.
>
>
>  
>

Me either without more thought.

If we start logging to a file explicitly, do we need to revisit the log 
rotation discussion which seems to have gone nowhere several times recently?

cheers

andrew

Thu, 10 Jun 2004 02:26:33 -0400
Andrew Dunstan <andrew@dunslane.net>
Re: [PATCHES] serverlog function (log_destination file)
Tom Lane wrote:

>Bruce Momjian <pgman@candle.pha.pa.us> writes:
>  
>
>>Looks good to me.  The only issue I saw was that the default file name
>>mentioned in postgresql.conf doesn't match the actual default.
>>    
>>
>
>I'm really not happy with the concept that the postmaster overrides
>its stderr direction.
>
>  
>
I agree, that's why I implemented it as *additional* log_destination.

Regards,
Andreas



Thu, 10 Jun 2004 22:36:04 +0200
Andreas Pflug <pgadmin@pse-consulting.de>
Re: [PATCHES] serverlog function (log_destination file)
Andreas Pflug wrote:
> Tom Lane wrote:
> 
> >Bruce Momjian <pgman@candle.pha.pa.us> writes:
> >  
> >
> >>Looks good to me.  The only issue I saw was that the default file name
> >>mentioned in postgresql.conf doesn't match the actual default.
> >>    
> >>
> >
> >I'm really not happy with the concept that the postmaster overrides
> >its stderr direction.
> >
> >  
> >
> I agree, that's why I implemented it as *additional* log_destination.

One idea would be to send a message to stderr when this option is used
stating that everything is going to 'filename'.  

Also can we close/reopen the file on SIGHUP. My guess is we can't
because of all the backends accessing the output file.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 10 Jun 2004 16:37:26 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)
Sorry I didn't get back on this earlier, yesterday morning my internet 
access was literally struck by lightning, I'm running temporary hardware 
now.

Bruce Momjian wrote:

>>>>Looks good to me.  The only issue I saw was that the default file name
>>>>mentioned in postgresql.conf doesn't match the actual default.
>>>>        
>>>>

I'll fix the default filename difference, postgresql.log seems best. 
I'll add doc too.

>One idea would be to send a message to stderr when this option is used
>stating that everything is going to 'filename'.  
>  
>
I can ereport LogFileOpen and LogFileClose, do we need this? Currently, 
only open problems will be reported.

>Also can we close/reopen the file on SIGHUP. My guess is we can't
>because of all the backends accessing the output file.
>  
>
I'd also like it flushed in pg_logfile and pg_logfile_length, same 
problem; any hints welcome.

Regards,
Andreas



Thu, 10 Jun 2004 22:54:54 +0200
Andreas Pflug <pgadmin@pse-consulting.de>
Re: [PATCHES] serverlog function (log_destination file)
Andreas Pflug wrote:
> Sorry I didn't get back on this earlier, yesterday morning my internet 
> access was literally struck by lightning, I'm running temporary hardware 
> now.
> 
> Bruce Momjian wrote:
> 
> >>>>Looks good to me.  The only issue I saw was that the default file name
> >>>>mentioned in postgresql.conf doesn't match the actual default.
> >>>>        
> >>>>
> 
> I'll fix the default filename difference, postgresql.log seems best. 
> I'll add doc too.
> 
> >One idea would be to send a message to stderr when this option is used
> >stating that everything is going to 'filename'.  
> >  
> >
> I can ereport LogFileOpen and LogFileClose, do we need this? Currently, 
> only open problems will be reported.


Actually, my idea of sending a message to stderr saying we are using a
pre-configured file is so folks aren't surprised by the fact they can't
see any stderr anymore.  But doesn't syslog have the same issue.  Maybe
not, and that's why we need a message like:

	"All standard output and standard error are going to postgresql.conf"

and send that to the processes standard error.

> 
> >Also can we close/reopen the file on SIGHUP. My guess is we can't
> >because of all the backends accessing the output file.
> >  
> >
> I'd also like it flushed in pg_logfile and pg_logfile_length, same 
> problem; any hints welcome.

I don't understand this.  I was thinking of close/reopen so log files
could be rotated.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 10 Jun 2004 17:26:29 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)
Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Actually, my idea of sending a message to stderr saying we are using a
> pre-configured file is so folks aren't surprised by the fact they can't
> see any stderr anymore.

Hm?  I thought we'd just established that the patch wasn't going to
suppress output to stderr.

			regards, tom lane

Thu, 10 Jun 2004 17:56:43 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: [PATCHES] serverlog function (log_destination file) 
Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Actually, my idea of sending a message to stderr saying we are using a
> > pre-configured file is so folks aren't surprised by the fact they can't
> > see any stderr anymore.
> 
> Hm?  I thought we'd just established that the patch wasn't going to
> suppress output to stderr.

Oh, I didn't see that.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 10 Jun 2004 17:57:33 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)
Bruce Momjian wrote:

>I was thinking of close/reopen so log files
>could be rotated.
>
>  
>
Log file rotation is fine, if we find a consensus quite soon how to 
implement it... Seems as if I might find some time to implement it until 
feature freeze.

The attached patch has the default filename issue fixed, and 
documentation. Since I don't have a doc build system functional, there 
might be tag mismatches or other typos; please check. IMHO this should 
be committed without waiting for log rotation stuff.

Regards,
Andreas
Fri, 11 Jun 2004 20:07:02 +0200
Andreas Pflug <pgadmin@pse-consulting.de>
Re: [PATCHES] serverlog function (log_destination file)
Andreas Pflug <pgadmin@pse-consulting.de> writes:
> The attached patch has the default filename issue fixed, and 
> documentation. Since I don't have a doc build system functional, there 
> might be tag mismatches or other typos; please check. IMHO this should 
> be committed without waiting for log rotation stuff.

This has got portability issues (fopen("ab")) and I don't care for its
use of malloc in preference to palloc either.  Also, pg_logfile() will
dump core if LogFileName returns null.

The bigger issue though is whether this is useful at all, if you cannot
solve the file rotation issue (and I don't think you can).  As
implemented, the secondary log file cannot be truncated without
restarting the postmaster.  I think that reduces it from a possibly
useful feature to a useless toy.  (The fact that pg_logfile_length
returns int and not something wider is pretty silly in this connection.)

My vote is not to apply until and unless something that can rotate the
logfile is demonstrated ...

			regards, tom lane

Fri, 11 Jun 2004 14:20:26 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: [PATCHES] serverlog function (log_destination file) 
Tom Lane wrote:
> Andreas Pflug <pgadmin@pse-consulting.de> writes:
> > The attached patch has the default filename issue fixed, and 
> > documentation. Since I don't have a doc build system functional, there 
> > might be tag mismatches or other typos; please check. IMHO this should 
> > be committed without waiting for log rotation stuff.
> 
> This has got portability issues (fopen("ab")) and I don't care for its
> use of malloc in preference to palloc either.  Also, pg_logfile() will
> dump core if LogFileName returns null.
> 
> The bigger issue though is whether this is useful at all, if you cannot
> solve the file rotation issue (and I don't think you can).  As
> implemented, the secondary log file cannot be truncated without
> restarting the postmaster.  I think that reduces it from a possibly
> useful feature to a useless toy.  (The fact that pg_logfile_length
> returns int and not something wider is pretty silly in this connection.)
> 
> My vote is not to apply until and unless something that can rotate the
> logfile is demonstrated ...

Agreed.  Lets see where it goes.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Fri, 11 Jun 2004 14:25:03 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)
Tom Lane wrote:

>
>This has got portability issues (fopen("ab"))
>
My doc says b is ignored on ansi systems, and recommends using it. Do 
you have other experiences?

> and I don't care for its
>use of malloc in preference to palloc either.  
>
Do we already have an applicable memory context in the postmaster at 
that early stage of initialization?

>Also, pg_logfile() will dump core if LogFileName returns null.
>  
>
How that?

char *filename=LogFileName();
if (filename)
{
       ...
     free(filename);
}

>The bigger issue though is whether this is useful at all, if you cannot
>solve the file rotation issue (and I don't think you can).  As
>implemented, the secondary log file cannot be truncated without
>restarting the postmaster.  I think that reduces it from a possibly
>useful feature to a useless toy. 
>
This patch isn't trying to be better on logfile handling than the 
default stderr redirection behavior, besides being able to access it 
through the postmaster. Seems you insist to name this a toy, many users 
don't.

> (The fact that pg_logfile_length
>returns int and not something wider is pretty silly in this connection.)
>  
>
2GB logfile seems pretty big...

Regards,
Andreas


Fri, 11 Jun 2004 21:05:57 +0200
Andreas Pflug <pgadmin@pse-consulting.de>
Re: [PATCHES] serverlog function (log_destination file)

Were are we on this?

---------------------------------------------------------------------------

Andreas Pflug wrote:
> Tom Lane wrote:
> 
> >
> >This has got portability issues (fopen("ab"))
> >
> My doc says b is ignored on ansi systems, and recommends using it. Do 
> you have other experiences?
> 
> > and I don't care for its
> >use of malloc in preference to palloc either.  
> >
> Do we already have an applicable memory context in the postmaster at 
> that early stage of initialization?
> 
> >Also, pg_logfile() will dump core if LogFileName returns null.
> >  
> >
> How that?
> 
> char *filename=LogFileName();
> if (filename)
> {
>        ...
>      free(filename);
> }
> 
> >The bigger issue though is whether this is useful at all, if you cannot
> >solve the file rotation issue (and I don't think you can).  As
> >implemented, the secondary log file cannot be truncated without
> >restarting the postmaster.  I think that reduces it from a possibly
> >useful feature to a useless toy. 
> >
> This patch isn't trying to be better on logfile handling than the 
> default stderr redirection behavior, besides being able to access it 
> through the postmaster. Seems you insist to name this a toy, many users 
> don't.
> 
> > (The fact that pg_logfile_length
> >returns int and not something wider is pretty silly in this connection.)
> >  
> >
> 2GB logfile seems pretty big...
> 
> Regards,
> Andreas
> 
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 5: Have you checked our extensive FAQ?
> 
>                http://www.postgresql.org/docs/faqs/FAQ.html
> 

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Fri, 18 Jun 2004 23:04:47 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: [PATCHES] serverlog function (log_destination file)