Adding upstream version 15.5.upstream/15.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3458 insertions, 0 deletions

diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
new file mode 100644
index 0000000..6fa4f2c
--- /dev/null
+++ b/src/backend/utils/error/elog.c
@@ -0,0 +1,3458 @@
+/*-------------------------------------------------------------------------
+ *
+ * elog.c
+ *	  error logging and reporting
+ *
+ * Because of the extremely high rate at which log messages can be generated,
+ * we need to be mindful of the performance cost of obtaining any information
+ * that may be logged.  Also, it's important to keep in mind that this code may
+ * get called from within an aborted transaction, in which case operations
+ * such as syscache lookups are unsafe.
+ *
+ * Some notes about recursion and errors during error processing:
+ *
+ * We need to be robust about recursive-error scenarios --- for example,
+ * if we run out of memory, it's important to be able to report that fact.
+ * There are a number of considerations that go into this.
+ *
+ * First, distinguish between re-entrant use and actual recursion.  It
+ * is possible for an error or warning message to be emitted while the
+ * parameters for an error message are being computed.  In this case
+ * errstart has been called for the outer message, and some field values
+ * may have already been saved, but we are not actually recursing.  We handle
+ * this by providing a (small) stack of ErrorData records.  The inner message
+ * can be computed and sent without disturbing the state of the outer message.
+ * (If the inner message is actually an error, this isn't very interesting
+ * because control won't come back to the outer message generator ... but
+ * if the inner message is only debug or log data, this is critical.)
+ *
+ * Second, actual recursion will occur if an error is reported by one of
+ * the elog.c routines or something they call.  By far the most probable
+ * scenario of this sort is "out of memory"; and it's also the nastiest
+ * to handle because we'd likely also run out of memory while trying to
+ * report this error!  Our escape hatch for this case is to reset the
+ * ErrorContext to empty before trying to process the inner error.  Since
+ * ErrorContext is guaranteed to have at least 8K of space in it (see mcxt.c),
+ * we should be able to process an "out of memory" message successfully.
+ * Since we lose the prior error state due to the reset, we won't be able
+ * to return to processing the original error, but we wouldn't have anyway.
+ * (NOTE: the escape hatch is not used for recursive situations where the
+ * inner message is of less than ERROR severity; in that case we just
+ * try to process it and return normally.  Usually this will work, but if
+ * it ends up in infinite recursion, we will PANIC due to error stack
+ * overflow.)
+ *
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/error/elog.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <fcntl.h>
+#include <time.h>
+#include <unistd.h>
+#include <signal.h>
+#include <ctype.h>
+#ifdef HAVE_SYSLOG
+#include <syslog.h>
+#endif
+#ifdef HAVE_EXECINFO_H
+#include <execinfo.h>
+#endif
+
+#include "access/transam.h"
+#include "access/xact.h"
+#include "libpq/libpq.h"
+#include "libpq/pqformat.h"
+#include "mb/pg_wchar.h"
+#include "miscadmin.h"
+#include "pgstat.h"
+#include "postmaster/bgworker.h"
+#include "postmaster/postmaster.h"
+#include "postmaster/syslogger.h"
+#include "storage/ipc.h"
+#include "storage/proc.h"
+#include "tcop/tcopprot.h"
+#include "utils/guc.h"
+#include "utils/memutils.h"
+#include "utils/ps_status.h"
+
+
+/* In this module, access gettext() via err_gettext() */
+#undef _
+#define _(x) err_gettext(x)
+
+
+/* Global variables */
+ErrorContextCallback *error_context_stack = NULL;
+
+sigjmp_buf *PG_exception_stack = NULL;
+
+extern bool redirection_done;
+
+/*
+ * Hook for intercepting messages before they are sent to the server log.
+ * Note that the hook will not get called for messages that are suppressed
+ * by log_min_messages.  Also note that logging hooks implemented in preload
+ * libraries will miss any log messages that are generated before the
+ * library is loaded.
+ */
+emit_log_hook_type emit_log_hook = NULL;
+
+/* GUC parameters */
+int			Log_error_verbosity = PGERROR_VERBOSE;
+char	   *Log_line_prefix = NULL; /* format for extra log line info */
+int			Log_destination = LOG_DESTINATION_STDERR;
+char	   *Log_destination_string = NULL;
+bool		syslog_sequence_numbers = true;
+bool		syslog_split_messages = true;
+
+#ifdef HAVE_SYSLOG
+
+/*
+ * Max string length to send to syslog().  Note that this doesn't count the
+ * sequence-number prefix we add, and of course it doesn't count the prefix
+ * added by syslog itself.  Solaris and sysklogd truncate the final message
+ * at 1024 bytes, so this value leaves 124 bytes for those prefixes.  (Most
+ * other syslog implementations seem to have limits of 2KB or so.)
+ */
+#ifndef PG_SYSLOG_LIMIT
+#define PG_SYSLOG_LIMIT 900
+#endif
+
+static bool openlog_done = false;
+static char *syslog_ident = NULL;
+static int	syslog_facility = LOG_LOCAL0;
+
+static void write_syslog(int level, const char *line);
+#endif
+
+#ifdef WIN32
+extern char *event_source;
+
+static void write_eventlog(int level, const char *line, int len);
+#endif
+
+/* We provide a small stack of ErrorData records for re-entrant cases */
+#define ERRORDATA_STACK_SIZE  5
+
+static ErrorData errordata[ERRORDATA_STACK_SIZE];
+
+static int	errordata_stack_depth = -1; /* index of topmost active frame */
+
+static int	recursion_depth = 0;	/* to detect actual recursion */
+
+/*
+ * Saved timeval and buffers for formatted timestamps that might be used by
+ * both log_line_prefix and csv logs.
+ */
+static struct timeval saved_timeval;
+static bool saved_timeval_set = false;
+
+#define FORMATTED_TS_LEN 128
+static char formatted_start_time[FORMATTED_TS_LEN];
+static char formatted_log_time[FORMATTED_TS_LEN];
+
+
+/* Macro for checking errordata_stack_depth is reasonable */
+#define CHECK_STACK_DEPTH() \
+	do { \
+		if (errordata_stack_depth < 0) \
+		{ \
+			errordata_stack_depth = -1; \
+			ereport(ERROR, (errmsg_internal("errstart was not called"))); \
+		} \
+	} while (0)
+
+
+static const char *err_gettext(const char *str) pg_attribute_format_arg(1);
+static pg_noinline void set_backtrace(ErrorData *edata, int num_skip);
+static void set_errdata_field(MemoryContextData *cxt, char **ptr, const char *str);
+static void write_console(const char *line, int len);
+static const char *process_log_prefix_padding(const char *p, int *padding);
+static void log_line_prefix(StringInfo buf, ErrorData *edata);
+static void send_message_to_server_log(ErrorData *edata);
+static void send_message_to_frontend(ErrorData *edata);
+static void append_with_tabs(StringInfo buf, const char *str);
+
+
+/*
+ * is_log_level_output -- is elevel logically >= log_min_level?
+ *
+ * We use this for tests that should consider LOG to sort out-of-order,
+ * between ERROR and FATAL.  Generally this is the right thing for testing
+ * whether a message should go to the postmaster log, whereas a simple >=
+ * test is correct for testing whether the message should go to the client.
+ */
+static inline bool
+is_log_level_output(int elevel, int log_min_level)
+{
+	if (elevel == LOG || elevel == LOG_SERVER_ONLY)
+	{
+		if (log_min_level == LOG || log_min_level <= ERROR)
+			return true;
+	}
+	else if (elevel == WARNING_CLIENT_ONLY)
+	{
+		/* never sent to log, regardless of log_min_level */
+		return false;
+	}
+	else if (log_min_level == LOG)
+	{
+		/* elevel != LOG */
+		if (elevel >= FATAL)
+			return true;
+	}
+	/* Neither is LOG */
+	else if (elevel >= log_min_level)
+		return true;
+
+	return false;
+}
+
+/*
+ * Policy-setting subroutines.  These are fairly simple, but it seems wise
+ * to have the code in just one place.
+ */
+
+/*
+ * should_output_to_server --- should message of given elevel go to the log?
+ */
+static inline bool
+should_output_to_server(int elevel)
+{
+	return is_log_level_output(elevel, log_min_messages);
+}
+
+/*
+ * should_output_to_client --- should message of given elevel go to the client?
+ */
+static inline bool
+should_output_to_client(int elevel)
+{
+	if (whereToSendOutput == DestRemote && elevel != LOG_SERVER_ONLY)
+	{
+		/*
+		 * client_min_messages is honored only after we complete the
+		 * authentication handshake.  This is required both for security
+		 * reasons and because many clients can't handle NOTICE messages
+		 * during authentication.
+		 */
+		if (ClientAuthInProgress)
+			return (elevel >= ERROR);
+		else
+			return (elevel >= client_min_messages || elevel == INFO);
+	}
+	return false;
+}
+
+
+/*
+ * message_level_is_interesting --- would ereport/elog do anything?
+ *
+ * Returns true if ereport/elog with this elevel will not be a no-op.
+ * This is useful to short-circuit any expensive preparatory work that
+ * might be needed for a logging message.  There is no point in
+ * prepending this to a bare ereport/elog call, however.
+ */
+bool
+message_level_is_interesting(int elevel)
+{
+	/*
+	 * Keep this in sync with the decision-making in errstart().
+	 */
+	if (elevel >= ERROR ||
+		should_output_to_server(elevel) ||
+		should_output_to_client(elevel))
+		return true;
+	return false;
+}
+
+
+/*
+ * in_error_recursion_trouble --- are we at risk of infinite error recursion?
+ *
+ * This function exists to provide common control of various fallback steps
+ * that we take if we think we are facing infinite error recursion.  See the
+ * callers for details.
+ */
+bool
+in_error_recursion_trouble(void)
+{
+	/* Pull the plug if recurse more than once */
+	return (recursion_depth > 2);
+}
+
+/*
+ * One of those fallback steps is to stop trying to localize the error
+ * message, since there's a significant probability that that's exactly
+ * what's causing the recursion.
+ */
+static inline const char *
+err_gettext(const char *str)
+{
+#ifdef ENABLE_NLS
+	if (in_error_recursion_trouble())
+		return str;
+	else
+		return gettext(str);
+#else
+	return str;
+#endif
+}
+
+/*
+ * errstart_cold
+ *		A simple wrapper around errstart, but hinted to be "cold".  Supporting
+ *		compilers are more likely to move code for branches containing this
+ *		function into an area away from the calling function's code.  This can
+ *		result in more commonly executed code being more compact and fitting
+ *		on fewer cache lines.
+ */
+pg_attribute_cold bool
+errstart_cold(int elevel, const char *domain)
+{
+	return errstart(elevel, domain);
+}
+
+/*
+ * errstart --- begin an error-reporting cycle
+ *
+ * Create and initialize error stack entry.  Subsequently, errmsg() and
+ * perhaps other routines will be called to further populate the stack entry.
+ * Finally, errfinish() will be called to actually process the error report.
+ *
+ * Returns true in normal case.  Returns false to short-circuit the error
+ * report (if it's a warning or lower and not to be reported anywhere).
+ */
+bool
+errstart(int elevel, const char *domain)
+{
+	ErrorData  *edata;
+	bool		output_to_server;
+	bool		output_to_client = false;
+	int			i;
+
+	/*
+	 * Check some cases in which we want to promote an error into a more
+	 * severe error.  None of this logic applies for non-error messages.
+	 */
+	if (elevel >= ERROR)
+	{
+		/*
+		 * If we are inside a critical section, all errors become PANIC
+		 * errors.  See miscadmin.h.
+		 */
+		if (CritSectionCount > 0)
+			elevel = PANIC;
+
+		/*
+		 * Check reasons for treating ERROR as FATAL:
+		 *
+		 * 1. we have no handler to pass the error to (implies we are in the
+		 * postmaster or in backend startup).
+		 *
+		 * 2. ExitOnAnyError mode switch is set (initdb uses this).
+		 *
+		 * 3. the error occurred after proc_exit has begun to run.  (It's
+		 * proc_exit's responsibility to see that this doesn't turn into
+		 * infinite recursion!)
+		 */
+		if (elevel == ERROR)
+		{
+			if (PG_exception_stack == NULL ||
+				ExitOnAnyError ||
+				proc_exit_inprogress)
+				elevel = FATAL;
+		}
+
+		/*
+		 * If the error level is ERROR or more, errfinish is not going to
+		 * return to caller; therefore, if there is any stacked error already
+		 * in progress it will be lost.  This is more or less okay, except we
+		 * do not want to have a FATAL or PANIC error downgraded because the
+		 * reporting process was interrupted by a lower-grade error.  So check
+		 * the stack and make sure we panic if panic is warranted.
+		 */
+		for (i = 0; i <= errordata_stack_depth; i++)
+			elevel = Max(elevel, errordata[i].elevel);
+	}
+
+	/*
+	 * Now decide whether we need to process this report at all; if it's
+	 * warning or less and not enabled for logging, just return false without
+	 * starting up any error logging machinery.
+	 */
+	output_to_server = should_output_to_server(elevel);
+	output_to_client = should_output_to_client(elevel);
+	if (elevel < ERROR && !output_to_server && !output_to_client)
+		return false;
+
+	/*
+	 * We need to do some actual work.  Make sure that memory context
+	 * initialization has finished, else we can't do anything useful.
+	 */
+	if (ErrorContext == NULL)
+	{
+		/* Oops, hard crash time; very little we can do safely here */
+		write_stderr("error occurred before error message processing is available\n");
+		exit(2);
+	}
+
+	/*
+	 * Okay, crank up a stack entry to store the info in.
+	 */
+
+	if (recursion_depth++ > 0 && elevel >= ERROR)
+	{
+		/*
+		 * Oops, error during error processing.  Clear ErrorContext as
+		 * discussed at top of file.  We will not return to the original
+		 * error's reporter or handler, so we don't need it.
+		 */
+		MemoryContextReset(ErrorContext);
+
+		/*
+		 * Infinite error recursion might be due to something broken in a
+		 * context traceback routine.  Abandon them too.  We also abandon
+		 * attempting to print the error statement (which, if long, could
+		 * itself be the source of the recursive failure).
+		 */
+		if (in_error_recursion_trouble())
+		{
+			error_context_stack = NULL;
+			debug_query_string = NULL;
+		}
+	}
+	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
+	{
+		/*
+		 * Wups, stack not big enough.  We treat this as a PANIC condition
+		 * because it suggests an infinite loop of errors during error
+		 * recovery.
+		 */
+		errordata_stack_depth = -1; /* make room on stack */
+		ereport(PANIC, (errmsg_internal("ERRORDATA_STACK_SIZE exceeded")));
+	}
+
+	/* Initialize data for this error frame */
+	edata = &errordata[errordata_stack_depth];
+	MemSet(edata, 0, sizeof(ErrorData));
+	edata->elevel = elevel;
+	edata->output_to_server = output_to_server;
+	edata->output_to_client = output_to_client;
+	/* the default text domain is the backend's */
+	edata->domain = domain ? domain : PG_TEXTDOMAIN("postgres");
+	/* initialize context_domain the same way (see set_errcontext_domain()) */
+	edata->context_domain = edata->domain;
+	/* Select default errcode based on elevel */
+	if (elevel >= ERROR)
+		edata->sqlerrcode = ERRCODE_INTERNAL_ERROR;
+	else if (elevel >= WARNING)
+		edata->sqlerrcode = ERRCODE_WARNING;
+	else
+		edata->sqlerrcode = ERRCODE_SUCCESSFUL_COMPLETION;
+	/* errno is saved here so that error parameter eval can't change it */
+	edata->saved_errno = errno;
+
+	/*
+	 * Any allocations for this error state level should go into ErrorContext
+	 */
+	edata->assoc_context = ErrorContext;
+
+	recursion_depth--;
+	return true;
+}
+
+/*
+ * Checks whether the given funcname matches backtrace_functions; see
+ * check_backtrace_functions.
+ */
+static bool
+matches_backtrace_functions(const char *funcname)
+{
+	char	   *p;
+
+	if (!backtrace_symbol_list || funcname == NULL || funcname[0] == '\0')
+		return false;
+
+	p = backtrace_symbol_list;
+	for (;;)
+	{
+		if (*p == '\0')			/* end of backtrace_symbol_list */
+			break;
+
+		if (strcmp(funcname, p) == 0)
+			return true;
+		p += strlen(p) + 1;
+	}
+
+	return false;
+}
+
+/*
+ * errfinish --- end an error-reporting cycle
+ *
+ * Produce the appropriate error report(s) and pop the error stack.
+ *
+ * If elevel, as passed to errstart(), is ERROR or worse, control does not
+ * return to the caller.  See elog.h for the error level definitions.
+ */
+void
+errfinish(const char *filename, int lineno, const char *funcname)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	int			elevel;
+	MemoryContext oldcontext;
+	ErrorContextCallback *econtext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+
+	/* Save the last few bits of error state into the stack entry */
+	if (filename)
+	{
+		const char *slash;
+
+		/* keep only base name, useful especially for vpath builds */
+		slash = strrchr(filename, '/');
+		if (slash)
+			filename = slash + 1;
+		/* Some Windows compilers use backslashes in __FILE__ strings */
+		slash = strrchr(filename, '\\');
+		if (slash)
+			filename = slash + 1;
+	}
+
+	edata->filename = filename;
+	edata->lineno = lineno;
+	edata->funcname = funcname;
+
+	elevel = edata->elevel;
+
+	/*
+	 * Do processing in ErrorContext, which we hope has enough reserved space
+	 * to report an error.
+	 */
+	oldcontext = MemoryContextSwitchTo(ErrorContext);
+
+	if (!edata->backtrace &&
+		edata->funcname &&
+		backtrace_functions &&
+		matches_backtrace_functions(edata->funcname))
+		set_backtrace(edata, 2);
+
+	/*
+	 * Call any context callback functions.  Errors occurring in callback
+	 * functions will be treated as recursive errors --- this ensures we will
+	 * avoid infinite recursion (see errstart).
+	 */
+	for (econtext = error_context_stack;
+		 econtext != NULL;
+		 econtext = econtext->previous)
+		econtext->callback(econtext->arg);
+
+	/*
+	 * If ERROR (not more nor less) we pass it off to the current handler.
+	 * Printing it and popping the stack is the responsibility of the handler.
+	 */
+	if (elevel == ERROR)
+	{
+		/*
+		 * We do some minimal cleanup before longjmp'ing so that handlers can
+		 * execute in a reasonably sane state.
+		 *
+		 * Reset InterruptHoldoffCount in case we ereport'd from inside an
+		 * interrupt holdoff section.  (We assume here that no handler will
+		 * itself be inside a holdoff section.  If necessary, such a handler
+		 * could save and restore InterruptHoldoffCount for itself, but this
+		 * should make life easier for most.)
+		 */
+		InterruptHoldoffCount = 0;
+		QueryCancelHoldoffCount = 0;
+
+		CritSectionCount = 0;	/* should be unnecessary, but... */
+
+		/*
+		 * Note that we leave CurrentMemoryContext set to ErrorContext. The
+		 * handler should reset it to something else soon.
+		 */
+
+		recursion_depth--;
+		PG_RE_THROW();
+	}
+
+	/* Emit the message to the right places */
+	EmitErrorReport();
+
+	/* Now free up subsidiary data attached to stack entry, and release it */
+	if (edata->message)
+		pfree(edata->message);
+	if (edata->detail)
+		pfree(edata->detail);
+	if (edata->detail_log)
+		pfree(edata->detail_log);
+	if (edata->hint)
+		pfree(edata->hint);
+	if (edata->context)
+		pfree(edata->context);
+	if (edata->backtrace)
+		pfree(edata->backtrace);
+	if (edata->schema_name)
+		pfree(edata->schema_name);
+	if (edata->table_name)
+		pfree(edata->table_name);
+	if (edata->column_name)
+		pfree(edata->column_name);
+	if (edata->datatype_name)
+		pfree(edata->datatype_name);
+	if (edata->constraint_name)
+		pfree(edata->constraint_name);
+	if (edata->internalquery)
+		pfree(edata->internalquery);
+
+	errordata_stack_depth--;
+
+	/* Exit error-handling context */
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+
+	/*
+	 * Perform error recovery action as specified by elevel.
+	 */
+	if (elevel == FATAL)
+	{
+		/*
+		 * For a FATAL error, we let proc_exit clean up and exit.
+		 *
+		 * If we just reported a startup failure, the client will disconnect
+		 * on receiving it, so don't send any more to the client.
+		 */
+		if (PG_exception_stack == NULL && whereToSendOutput == DestRemote)
+			whereToSendOutput = DestNone;
+
+		/*
+		 * fflush here is just to improve the odds that we get to see the
+		 * error message, in case things are so hosed that proc_exit crashes.
+		 * Any other code you might be tempted to add here should probably be
+		 * in an on_proc_exit or on_shmem_exit callback instead.
+		 */
+		fflush(stdout);
+		fflush(stderr);
+
+		/*
+		 * Let the cumulative stats system know. Only mark the session as
+		 * terminated by fatal error if there is no other known cause.
+		 */
+		if (pgStatSessionEndCause == DISCONNECT_NORMAL)
+			pgStatSessionEndCause = DISCONNECT_FATAL;
+
+		/*
+		 * Do normal process-exit cleanup, then return exit code 1 to indicate
+		 * FATAL termination.  The postmaster may or may not consider this
+		 * worthy of panic, depending on which subprocess returns it.
+		 */
+		proc_exit(1);
+	}
+
+	if (elevel >= PANIC)
+	{
+		/*
+		 * Serious crash time. Postmaster will observe SIGABRT process exit
+		 * status and kill the other backends too.
+		 *
+		 * XXX: what if we are *in* the postmaster?  abort() won't kill our
+		 * children...
+		 */
+		fflush(stdout);
+		fflush(stderr);
+		abort();
+	}
+
+	/*
+	 * Check for cancel/die interrupt first --- this is so that the user can
+	 * stop a query emitting tons of notice or warning messages, even if it's
+	 * in a loop that otherwise fails to check for interrupts.
+	 */
+	CHECK_FOR_INTERRUPTS();
+}
+
+
+/*
+ * errcode --- add SQLSTATE error code to the current error
+ *
+ * The code is expected to be represented as per MAKE_SQLSTATE().
+ */
+int
+errcode(int sqlerrcode)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	edata->sqlerrcode = sqlerrcode;
+
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errcode_for_file_access --- add SQLSTATE error code to the current error
+ *
+ * The SQLSTATE code is chosen based on the saved errno value.  We assume
+ * that the failing operation was some type of disk file access.
+ *
+ * NOTE: the primary error message string should generally include %m
+ * when this is used.
+ */
+int
+errcode_for_file_access(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	switch (edata->saved_errno)
+	{
+			/* Permission-denied failures */
+		case EPERM:				/* Not super-user */
+		case EACCES:			/* Permission denied */
+#ifdef EROFS
+		case EROFS:				/* Read only file system */
+#endif
+			edata->sqlerrcode = ERRCODE_INSUFFICIENT_PRIVILEGE;
+			break;
+
+			/* File not found */
+		case ENOENT:			/* No such file or directory */
+			edata->sqlerrcode = ERRCODE_UNDEFINED_FILE;
+			break;
+
+			/* Duplicate file */
+		case EEXIST:			/* File exists */
+			edata->sqlerrcode = ERRCODE_DUPLICATE_FILE;
+			break;
+
+			/* Wrong object type or state */
+		case ENOTDIR:			/* Not a directory */
+		case EISDIR:			/* Is a directory */
+#if defined(ENOTEMPTY) && (ENOTEMPTY != EEXIST) /* same code on AIX */
+		case ENOTEMPTY:			/* Directory not empty */
+#endif
+			edata->sqlerrcode = ERRCODE_WRONG_OBJECT_TYPE;
+			break;
+
+			/* Insufficient resources */
+		case ENOSPC:			/* No space left on device */
+			edata->sqlerrcode = ERRCODE_DISK_FULL;
+			break;
+
+		case ENFILE:			/* File table overflow */
+		case EMFILE:			/* Too many open files */
+			edata->sqlerrcode = ERRCODE_INSUFFICIENT_RESOURCES;
+			break;
+
+			/* Hardware failure */
+		case EIO:				/* I/O error */
+			edata->sqlerrcode = ERRCODE_IO_ERROR;
+			break;
+
+			/* All else is classified as internal errors */
+		default:
+			edata->sqlerrcode = ERRCODE_INTERNAL_ERROR;
+			break;
+	}
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * errcode_for_socket_access --- add SQLSTATE error code to the current error
+ *
+ * The SQLSTATE code is chosen based on the saved errno value.  We assume
+ * that the failing operation was some type of socket access.
+ *
+ * NOTE: the primary error message string should generally include %m
+ * when this is used.
+ */
+int
+errcode_for_socket_access(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	switch (edata->saved_errno)
+	{
+			/* Loss of connection */
+		case ALL_CONNECTION_FAILURE_ERRNOS:
+			edata->sqlerrcode = ERRCODE_CONNECTION_FAILURE;
+			break;
+
+			/* All else is classified as internal errors */
+		default:
+			edata->sqlerrcode = ERRCODE_INTERNAL_ERROR;
+			break;
+	}
+
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * This macro handles expansion of a format string and associated parameters;
+ * it's common code for errmsg(), errdetail(), etc.  Must be called inside
+ * a routine that is declared like "const char *fmt, ..." and has an edata
+ * pointer set up.  The message is assigned to edata->targetfield, or
+ * appended to it if appendval is true.  The message is subject to translation
+ * if translateit is true.
+ *
+ * Note: we pstrdup the buffer rather than just transferring its storage
+ * to the edata field because the buffer might be considerably larger than
+ * really necessary.
+ */
+#define EVALUATE_MESSAGE(domain, targetfield, appendval, translateit)	\
+	{ \
+		StringInfoData	buf; \
+		/* Internationalize the error format string */ \
+		if ((translateit) && !in_error_recursion_trouble()) \
+			fmt = dgettext((domain), fmt);				  \
+		initStringInfo(&buf); \
+		if ((appendval) && edata->targetfield) { \
+			appendStringInfoString(&buf, edata->targetfield); \
+			appendStringInfoChar(&buf, '\n'); \
+		} \
+		/* Generate actual output --- have to use appendStringInfoVA */ \
+		for (;;) \
+		{ \
+			va_list		args; \
+			int			needed; \
+			errno = edata->saved_errno; \
+			va_start(args, fmt); \
+			needed = appendStringInfoVA(&buf, fmt, args); \
+			va_end(args); \
+			if (needed == 0) \
+				break; \
+			enlargeStringInfo(&buf, needed); \
+		} \
+		/* Save the completed message into the stack item */ \
+		if (edata->targetfield) \
+			pfree(edata->targetfield); \
+		edata->targetfield = pstrdup(buf.data); \
+		pfree(buf.data); \
+	}
+
+/*
+ * Same as above, except for pluralized error messages.  The calling routine
+ * must be declared like "const char *fmt_singular, const char *fmt_plural,
+ * unsigned long n, ...".  Translation is assumed always wanted.
+ */
+#define EVALUATE_MESSAGE_PLURAL(domain, targetfield, appendval)  \
+	{ \
+		const char	   *fmt; \
+		StringInfoData	buf; \
+		/* Internationalize the error format string */ \
+		if (!in_error_recursion_trouble()) \
+			fmt = dngettext((domain), fmt_singular, fmt_plural, n); \
+		else \
+			fmt = (n == 1 ? fmt_singular : fmt_plural); \
+		initStringInfo(&buf); \
+		if ((appendval) && edata->targetfield) { \
+			appendStringInfoString(&buf, edata->targetfield); \
+			appendStringInfoChar(&buf, '\n'); \
+		} \
+		/* Generate actual output --- have to use appendStringInfoVA */ \
+		for (;;) \
+		{ \
+			va_list		args; \
+			int			needed; \
+			errno = edata->saved_errno; \
+			va_start(args, n); \
+			needed = appendStringInfoVA(&buf, fmt, args); \
+			va_end(args); \
+			if (needed == 0) \
+				break; \
+			enlargeStringInfo(&buf, needed); \
+		} \
+		/* Save the completed message into the stack item */ \
+		if (edata->targetfield) \
+			pfree(edata->targetfield); \
+		edata->targetfield = pstrdup(buf.data); \
+		pfree(buf.data); \
+	}
+
+
+/*
+ * errmsg --- add a primary error message text to the current error
+ *
+ * In addition to the usual %-escapes recognized by printf, "%m" in
+ * fmt is replaced by the error message for the caller's value of errno.
+ *
+ * Note: no newline is needed at the end of the fmt string, since
+ * ereport will provide one for the output methods that need it.
+ */
+int
+errmsg(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	edata->message_id = fmt;
+	EVALUATE_MESSAGE(edata->domain, message, false, true);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * Add a backtrace to the containing ereport() call.  This is intended to be
+ * added temporarily during debugging.
+ */
+int
+errbacktrace(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	set_backtrace(edata, 1);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+
+	return 0;
+}
+
+/*
+ * Compute backtrace data and add it to the supplied ErrorData.  num_skip
+ * specifies how many inner frames to skip.  Use this to avoid showing the
+ * internal backtrace support functions in the backtrace.  This requires that
+ * this and related functions are not inlined.
+ */
+static void
+set_backtrace(ErrorData *edata, int num_skip)
+{
+	StringInfoData errtrace;
+
+	initStringInfo(&errtrace);
+
+#ifdef HAVE_BACKTRACE_SYMBOLS
+	{
+		void	   *buf[100];
+		int			nframes;
+		char	  **strfrms;
+
+		nframes = backtrace(buf, lengthof(buf));
+		strfrms = backtrace_symbols(buf, nframes);
+		if (strfrms == NULL)
+			return;
+
+		for (int i = num_skip; i < nframes; i++)
+			appendStringInfo(&errtrace, "\n%s", strfrms[i]);
+		free(strfrms);
+	}
+#else
+	appendStringInfoString(&errtrace,
+						   "backtrace generation is not supported by this installation");
+#endif
+
+	edata->backtrace = errtrace.data;
+}
+
+/*
+ * errmsg_internal --- add a primary error message text to the current error
+ *
+ * This is exactly like errmsg() except that strings passed to errmsg_internal
+ * are not translated, and are customarily left out of the
+ * internationalization message dictionary.  This should be used for "can't
+ * happen" cases that are probably not worth spending translation effort on.
+ * We also use this for certain cases where we *must* not try to translate
+ * the message because the translation would fail and result in infinite
+ * error recursion.
+ */
+int
+errmsg_internal(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	edata->message_id = fmt;
+	EVALUATE_MESSAGE(edata->domain, message, false, false);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errmsg_plural --- add a primary error message text to the current error,
+ * with support for pluralization of the message text
+ */
+int
+errmsg_plural(const char *fmt_singular, const char *fmt_plural,
+			  unsigned long n,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	edata->message_id = fmt_singular;
+	EVALUATE_MESSAGE_PLURAL(edata->domain, message, false);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errdetail --- add a detail error message text to the current error
+ */
+int
+errdetail(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE(edata->domain, detail, false, true);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errdetail_internal --- add a detail error message text to the current error
+ *
+ * This is exactly like errdetail() except that strings passed to
+ * errdetail_internal are not translated, and are customarily left out of the
+ * internationalization message dictionary.  This should be used for detail
+ * messages that seem not worth translating for one reason or another
+ * (typically, that they don't seem to be useful to average users).
+ */
+int
+errdetail_internal(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE(edata->domain, detail, false, false);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errdetail_log --- add a detail_log error message text to the current error
+ */
+int
+errdetail_log(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE(edata->domain, detail_log, false, true);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * errdetail_log_plural --- add a detail_log error message text to the current error
+ * with support for pluralization of the message text
+ */
+int
+errdetail_log_plural(const char *fmt_singular, const char *fmt_plural,
+					 unsigned long n,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE_PLURAL(edata->domain, detail_log, false);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errdetail_plural --- add a detail error message text to the current error,
+ * with support for pluralization of the message text
+ */
+int
+errdetail_plural(const char *fmt_singular, const char *fmt_plural,
+				 unsigned long n,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE_PLURAL(edata->domain, detail, false);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errhint --- add a hint error message text to the current error
+ */
+int
+errhint(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE(edata->domain, hint, false, true);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errhint_plural --- add a hint error message text to the current error,
+ * with support for pluralization of the message text
+ */
+int
+errhint_plural(const char *fmt_singular, const char *fmt_plural,
+			   unsigned long n,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE_PLURAL(edata->domain, hint, false);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errcontext_msg --- add a context error message text to the current error
+ *
+ * Unlike other cases, multiple calls are allowed to build up a stack of
+ * context information.  We assume earlier calls represent more-closely-nested
+ * states.
+ */
+int
+errcontext_msg(const char *fmt,...)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	EVALUATE_MESSAGE(edata->context_domain, context, true, true);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * set_errcontext_domain --- set message domain to be used by errcontext()
+ *
+ * errcontext_msg() can be called from a different module than the original
+ * ereport(), so we cannot use the message domain passed in errstart() to
+ * translate it.  Instead, each errcontext_msg() call should be preceded by
+ * a set_errcontext_domain() call to specify the domain.  This is usually
+ * done transparently by the errcontext() macro.
+ */
+int
+set_errcontext_domain(const char *domain)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	/* the default text domain is the backend's */
+	edata->context_domain = domain ? domain : PG_TEXTDOMAIN("postgres");
+
+	return 0;					/* return value does not matter */
+}
+
+
+/*
+ * errhidestmt --- optionally suppress STATEMENT: field of log entry
+ *
+ * This should be called if the message text already includes the statement.
+ */
+int
+errhidestmt(bool hide_stmt)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	edata->hide_stmt = hide_stmt;
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * errhidecontext --- optionally suppress CONTEXT: field of log entry
+ *
+ * This should only be used for verbose debugging messages where the repeated
+ * inclusion of context would bloat the log volume too much.
+ */
+int
+errhidecontext(bool hide_ctx)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	edata->hide_ctx = hide_ctx;
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * errposition --- add cursor position to the current error
+ */
+int
+errposition(int cursorpos)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	edata->cursorpos = cursorpos;
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * internalerrposition --- add internal cursor position to the current error
+ */
+int
+internalerrposition(int cursorpos)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	edata->internalpos = cursorpos;
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * internalerrquery --- add internal query text to the current error
+ *
+ * Can also pass NULL to drop the internal query text entry.  This case
+ * is intended for use in error callback subroutines that are editorializing
+ * on the layout of the error report.
+ */
+int
+internalerrquery(const char *query)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	if (edata->internalquery)
+	{
+		pfree(edata->internalquery);
+		edata->internalquery = NULL;
+	}
+
+	if (query)
+		edata->internalquery = MemoryContextStrdup(edata->assoc_context, query);
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * err_generic_string -- used to set individual ErrorData string fields
+ * identified by PG_DIAG_xxx codes.
+ *
+ * This intentionally only supports fields that don't use localized strings,
+ * so that there are no translation considerations.
+ *
+ * Most potential callers should not use this directly, but instead prefer
+ * higher-level abstractions, such as errtablecol() (see relcache.c).
+ */
+int
+err_generic_string(int field, const char *str)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	switch (field)
+	{
+		case PG_DIAG_SCHEMA_NAME:
+			set_errdata_field(edata->assoc_context, &edata->schema_name, str);
+			break;
+		case PG_DIAG_TABLE_NAME:
+			set_errdata_field(edata->assoc_context, &edata->table_name, str);
+			break;
+		case PG_DIAG_COLUMN_NAME:
+			set_errdata_field(edata->assoc_context, &edata->column_name, str);
+			break;
+		case PG_DIAG_DATATYPE_NAME:
+			set_errdata_field(edata->assoc_context, &edata->datatype_name, str);
+			break;
+		case PG_DIAG_CONSTRAINT_NAME:
+			set_errdata_field(edata->assoc_context, &edata->constraint_name, str);
+			break;
+		default:
+			elog(ERROR, "unsupported ErrorData field id: %d", field);
+			break;
+	}
+
+	return 0;					/* return value does not matter */
+}
+
+/*
+ * set_errdata_field --- set an ErrorData string field
+ */
+static void
+set_errdata_field(MemoryContextData *cxt, char **ptr, const char *str)
+{
+	Assert(*ptr == NULL);
+	*ptr = MemoryContextStrdup(cxt, str);
+}
+
+/*
+ * geterrcode --- return the currently set SQLSTATE error code
+ *
+ * This is only intended for use in error callback subroutines, since there
+ * is no other place outside elog.c where the concept is meaningful.
+ */
+int
+geterrcode(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	return edata->sqlerrcode;
+}
+
+/*
+ * geterrposition --- return the currently set error position (0 if none)
+ *
+ * This is only intended for use in error callback subroutines, since there
+ * is no other place outside elog.c where the concept is meaningful.
+ */
+int
+geterrposition(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	return edata->cursorpos;
+}
+
+/*
+ * getinternalerrposition --- same for internal error position
+ *
+ * This is only intended for use in error callback subroutines, since there
+ * is no other place outside elog.c where the concept is meaningful.
+ */
+int
+getinternalerrposition(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	/* we don't bother incrementing recursion_depth */
+	CHECK_STACK_DEPTH();
+
+	return edata->internalpos;
+}
+
+
+/*
+ * Functions to allow construction of error message strings separately from
+ * the ereport() call itself.
+ *
+ * The expected calling convention is
+ *
+ *	pre_format_elog_string(errno, domain), var = format_elog_string(format,...)
+ *
+ * which can be hidden behind a macro such as GUC_check_errdetail().  We
+ * assume that any functions called in the arguments of format_elog_string()
+ * cannot result in re-entrant use of these functions --- otherwise the wrong
+ * text domain might be used, or the wrong errno substituted for %m.  This is
+ * okay for the current usage with GUC check hooks, but might need further
+ * effort someday.
+ *
+ * The result of format_elog_string() is stored in ErrorContext, and will
+ * therefore survive until FlushErrorState() is called.
+ */
+static int	save_format_errnumber;
+static const char *save_format_domain;
+
+void
+pre_format_elog_string(int errnumber, const char *domain)
+{
+	/* Save errno before evaluation of argument functions can change it */
+	save_format_errnumber = errnumber;
+	/* Save caller's text domain */
+	save_format_domain = domain;
+}
+
+char *
+format_elog_string(const char *fmt,...)
+{
+	ErrorData	errdata;
+	ErrorData  *edata;
+	MemoryContext oldcontext;
+
+	/* Initialize a mostly-dummy error frame */
+	edata = &errdata;
+	MemSet(edata, 0, sizeof(ErrorData));
+	/* the default text domain is the backend's */
+	edata->domain = save_format_domain ? save_format_domain : PG_TEXTDOMAIN("postgres");
+	/* set the errno to be used to interpret %m */
+	edata->saved_errno = save_format_errnumber;
+
+	oldcontext = MemoryContextSwitchTo(ErrorContext);
+
+	edata->message_id = fmt;
+	EVALUATE_MESSAGE(edata->domain, message, false, true);
+
+	MemoryContextSwitchTo(oldcontext);
+
+	return edata->message;
+}
+
+
+/*
+ * Actual output of the top-of-stack error message
+ *
+ * In the ereport(ERROR) case this is called from PostgresMain (or not at all,
+ * if the error is caught by somebody).  For all other severity levels this
+ * is called by errfinish.
+ */
+void
+EmitErrorReport(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	MemoryContext oldcontext;
+
+	recursion_depth++;
+	CHECK_STACK_DEPTH();
+	oldcontext = MemoryContextSwitchTo(edata->assoc_context);
+
+	/*
+	 * Call hook before sending message to log.  The hook function is allowed
+	 * to turn off edata->output_to_server, so we must recheck that afterward.
+	 * Making any other change in the content of edata is not considered
+	 * supported.
+	 *
+	 * Note: the reason why the hook can only turn off output_to_server, and
+	 * not turn it on, is that it'd be unreliable: we will never get here at
+	 * all if errstart() deems the message uninteresting.  A hook that could
+	 * make decisions in that direction would have to hook into errstart(),
+	 * where it would have much less information available.  emit_log_hook is
+	 * intended for custom log filtering and custom log message transmission
+	 * mechanisms.
+	 *
+	 * The log hook has access to both the translated and original English
+	 * error message text, which is passed through to allow it to be used as a
+	 * message identifier. Note that the original text is not available for
+	 * detail, detail_log, hint and context text elements.
+	 */
+	if (edata->output_to_server && emit_log_hook)
+		(*emit_log_hook) (edata);
+
+	/* Send to server log, if enabled */
+	if (edata->output_to_server)
+		send_message_to_server_log(edata);
+
+	/* Send to client, if enabled */
+	if (edata->output_to_client)
+		send_message_to_frontend(edata);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+}
+
+/*
+ * CopyErrorData --- obtain a copy of the topmost error stack entry
+ *
+ * This is only for use in error handler code.  The data is copied into the
+ * current memory context, so callers should always switch away from
+ * ErrorContext first; otherwise it will be lost when FlushErrorState is done.
+ */
+ErrorData *
+CopyErrorData(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+	ErrorData  *newedata;
+
+	/*
+	 * we don't increment recursion_depth because out-of-memory here does not
+	 * indicate a problem within the error subsystem.
+	 */
+	CHECK_STACK_DEPTH();
+
+	Assert(CurrentMemoryContext != ErrorContext);
+
+	/* Copy the struct itself */
+	newedata = (ErrorData *) palloc(sizeof(ErrorData));
+	memcpy(newedata, edata, sizeof(ErrorData));
+
+	/* Make copies of separately-allocated fields */
+	if (newedata->message)
+		newedata->message = pstrdup(newedata->message);
+	if (newedata->detail)
+		newedata->detail = pstrdup(newedata->detail);
+	if (newedata->detail_log)
+		newedata->detail_log = pstrdup(newedata->detail_log);
+	if (newedata->hint)
+		newedata->hint = pstrdup(newedata->hint);
+	if (newedata->context)
+		newedata->context = pstrdup(newedata->context);
+	if (newedata->backtrace)
+		newedata->backtrace = pstrdup(newedata->backtrace);
+	if (newedata->schema_name)
+		newedata->schema_name = pstrdup(newedata->schema_name);
+	if (newedata->table_name)
+		newedata->table_name = pstrdup(newedata->table_name);
+	if (newedata->column_name)
+		newedata->column_name = pstrdup(newedata->column_name);
+	if (newedata->datatype_name)
+		newedata->datatype_name = pstrdup(newedata->datatype_name);
+	if (newedata->constraint_name)
+		newedata->constraint_name = pstrdup(newedata->constraint_name);
+	if (newedata->internalquery)
+		newedata->internalquery = pstrdup(newedata->internalquery);
+
+	/* Use the calling context for string allocation */
+	newedata->assoc_context = CurrentMemoryContext;
+
+	return newedata;
+}
+
+/*
+ * FreeErrorData --- free the structure returned by CopyErrorData.
+ *
+ * Error handlers should use this in preference to assuming they know all
+ * the separately-allocated fields.
+ */
+void
+FreeErrorData(ErrorData *edata)
+{
+	if (edata->message)
+		pfree(edata->message);
+	if (edata->detail)
+		pfree(edata->detail);
+	if (edata->detail_log)
+		pfree(edata->detail_log);
+	if (edata->hint)
+		pfree(edata->hint);
+	if (edata->context)
+		pfree(edata->context);
+	if (edata->backtrace)
+		pfree(edata->backtrace);
+	if (edata->schema_name)
+		pfree(edata->schema_name);
+	if (edata->table_name)
+		pfree(edata->table_name);
+	if (edata->column_name)
+		pfree(edata->column_name);
+	if (edata->datatype_name)
+		pfree(edata->datatype_name);
+	if (edata->constraint_name)
+		pfree(edata->constraint_name);
+	if (edata->internalquery)
+		pfree(edata->internalquery);
+	pfree(edata);
+}
+
+/*
+ * FlushErrorState --- flush the error state after error recovery
+ *
+ * This should be called by an error handler after it's done processing
+ * the error; or as soon as it's done CopyErrorData, if it intends to
+ * do stuff that is likely to provoke another error.  You are not "out" of
+ * the error subsystem until you have done this.
+ */
+void
+FlushErrorState(void)
+{
+	/*
+	 * Reset stack to empty.  The only case where it would be more than one
+	 * deep is if we serviced an error that interrupted construction of
+	 * another message.  We assume control escaped out of that message
+	 * construction and won't ever go back.
+	 */
+	errordata_stack_depth = -1;
+	recursion_depth = 0;
+	/* Delete all data in ErrorContext */
+	MemoryContextResetAndDeleteChildren(ErrorContext);
+}
+
+/*
+ * ThrowErrorData --- report an error described by an ErrorData structure
+ *
+ * This is somewhat like ReThrowError, but it allows elevels besides ERROR,
+ * and the boolean flags such as output_to_server are computed via the
+ * default rules rather than being copied from the given ErrorData.
+ * This is primarily used to re-report errors originally reported by
+ * background worker processes and then propagated (with or without
+ * modification) to the backend responsible for them.
+ */
+void
+ThrowErrorData(ErrorData *edata)
+{
+	ErrorData  *newedata;
+	MemoryContext oldcontext;
+
+	if (!errstart(edata->elevel, edata->domain))
+		return;					/* error is not to be reported at all */
+
+	newedata = &errordata[errordata_stack_depth];
+	recursion_depth++;
+	oldcontext = MemoryContextSwitchTo(newedata->assoc_context);
+
+	/* Copy the supplied fields to the error stack entry. */
+	if (edata->sqlerrcode != 0)
+		newedata->sqlerrcode = edata->sqlerrcode;
+	if (edata->message)
+		newedata->message = pstrdup(edata->message);
+	if (edata->detail)
+		newedata->detail = pstrdup(edata->detail);
+	if (edata->detail_log)
+		newedata->detail_log = pstrdup(edata->detail_log);
+	if (edata->hint)
+		newedata->hint = pstrdup(edata->hint);
+	if (edata->context)
+		newedata->context = pstrdup(edata->context);
+	if (edata->backtrace)
+		newedata->backtrace = pstrdup(edata->backtrace);
+	/* assume message_id is not available */
+	if (edata->schema_name)
+		newedata->schema_name = pstrdup(edata->schema_name);
+	if (edata->table_name)
+		newedata->table_name = pstrdup(edata->table_name);
+	if (edata->column_name)
+		newedata->column_name = pstrdup(edata->column_name);
+	if (edata->datatype_name)
+		newedata->datatype_name = pstrdup(edata->datatype_name);
+	if (edata->constraint_name)
+		newedata->constraint_name = pstrdup(edata->constraint_name);
+	newedata->cursorpos = edata->cursorpos;
+	newedata->internalpos = edata->internalpos;
+	if (edata->internalquery)
+		newedata->internalquery = pstrdup(edata->internalquery);
+
+	MemoryContextSwitchTo(oldcontext);
+	recursion_depth--;
+
+	/* Process the error. */
+	errfinish(edata->filename, edata->lineno, edata->funcname);
+}
+
+/*
+ * ReThrowError --- re-throw a previously copied error
+ *
+ * A handler can do CopyErrorData/FlushErrorState to get out of the error
+ * subsystem, then do some processing, and finally ReThrowError to re-throw
+ * the original error.  This is slower than just PG_RE_THROW() but should
+ * be used if the "some processing" is likely to incur another error.
+ */
+void
+ReThrowError(ErrorData *edata)
+{
+	ErrorData  *newedata;
+
+	Assert(edata->elevel == ERROR);
+
+	/* Push the data back into the error context */
+	recursion_depth++;
+	MemoryContextSwitchTo(ErrorContext);
+
+	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
+	{
+		/*
+		 * Wups, stack not big enough.  We treat this as a PANIC condition
+		 * because it suggests an infinite loop of errors during error
+		 * recovery.
+		 */
+		errordata_stack_depth = -1; /* make room on stack */
+		ereport(PANIC, (errmsg_internal("ERRORDATA_STACK_SIZE exceeded")));
+	}
+
+	newedata = &errordata[errordata_stack_depth];
+	memcpy(newedata, edata, sizeof(ErrorData));
+
+	/* Make copies of separately-allocated fields */
+	if (newedata->message)
+		newedata->message = pstrdup(newedata->message);
+	if (newedata->detail)
+		newedata->detail = pstrdup(newedata->detail);
+	if (newedata->detail_log)
+		newedata->detail_log = pstrdup(newedata->detail_log);
+	if (newedata->hint)
+		newedata->hint = pstrdup(newedata->hint);
+	if (newedata->context)
+		newedata->context = pstrdup(newedata->context);
+	if (newedata->backtrace)
+		newedata->backtrace = pstrdup(newedata->backtrace);
+	if (newedata->schema_name)
+		newedata->schema_name = pstrdup(newedata->schema_name);
+	if (newedata->table_name)
+		newedata->table_name = pstrdup(newedata->table_name);
+	if (newedata->column_name)
+		newedata->column_name = pstrdup(newedata->column_name);
+	if (newedata->datatype_name)
+		newedata->datatype_name = pstrdup(newedata->datatype_name);
+	if (newedata->constraint_name)
+		newedata->constraint_name = pstrdup(newedata->constraint_name);
+	if (newedata->internalquery)
+		newedata->internalquery = pstrdup(newedata->internalquery);
+
+	/* Reset the assoc_context to be ErrorContext */
+	newedata->assoc_context = ErrorContext;
+
+	recursion_depth--;
+	PG_RE_THROW();
+}
+
+/*
+ * pg_re_throw --- out-of-line implementation of PG_RE_THROW() macro
+ */
+void
+pg_re_throw(void)
+{
+	/* If possible, throw the error to the next outer setjmp handler */
+	if (PG_exception_stack != NULL)
+		siglongjmp(*PG_exception_stack, 1);
+	else
+	{
+		/*
+		 * If we get here, elog(ERROR) was thrown inside a PG_TRY block, which
+		 * we have now exited only to discover that there is no outer setjmp
+		 * handler to pass the error to.  Had the error been thrown outside
+		 * the block to begin with, we'd have promoted the error to FATAL, so
+		 * the correct behavior is to make it FATAL now; that is, emit it and
+		 * then call proc_exit.
+		 */
+		ErrorData  *edata = &errordata[errordata_stack_depth];
+
+		Assert(errordata_stack_depth >= 0);
+		Assert(edata->elevel == ERROR);
+		edata->elevel = FATAL;
+
+		/*
+		 * At least in principle, the increase in severity could have changed
+		 * where-to-output decisions, so recalculate.
+		 */
+		edata->output_to_server = should_output_to_server(FATAL);
+		edata->output_to_client = should_output_to_client(FATAL);
+
+		/*
+		 * We can use errfinish() for the rest, but we don't want it to call
+		 * any error context routines a second time.  Since we know we are
+		 * about to exit, it should be OK to just clear the context stack.
+		 */
+		error_context_stack = NULL;
+
+		errfinish(edata->filename, edata->lineno, edata->funcname);
+	}
+
+	/* Doesn't return ... */
+	ExceptionalCondition("pg_re_throw tried to return", "FailedAssertion",
+						 __FILE__, __LINE__);
+}
+
+
+/*
+ * GetErrorContextStack - Return the context stack, for display/diags
+ *
+ * Returns a pstrdup'd string in the caller's context which includes the PG
+ * error call stack.  It is the caller's responsibility to ensure this string
+ * is pfree'd (or its context cleaned up) when done.
+ *
+ * This information is collected by traversing the error contexts and calling
+ * each context's callback function, each of which is expected to call
+ * errcontext() to return a string which can be presented to the user.
+ */
+char *
+GetErrorContextStack(void)
+{
+	ErrorData  *edata;
+	ErrorContextCallback *econtext;
+
+	/*
+	 * Okay, crank up a stack entry to store the info in.
+	 */
+	recursion_depth++;
+
+	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
+	{
+		/*
+		 * Wups, stack not big enough.  We treat this as a PANIC condition
+		 * because it suggests an infinite loop of errors during error
+		 * recovery.
+		 */
+		errordata_stack_depth = -1; /* make room on stack */
+		ereport(PANIC, (errmsg_internal("ERRORDATA_STACK_SIZE exceeded")));
+	}
+
+	/*
+	 * Things look good so far, so initialize our error frame
+	 */
+	edata = &errordata[errordata_stack_depth];
+	MemSet(edata, 0, sizeof(ErrorData));
+
+	/*
+	 * Set up assoc_context to be the caller's context, so any allocations
+	 * done (which will include edata->context) will use their context.
+	 */
+	edata->assoc_context = CurrentMemoryContext;
+
+	/*
+	 * Call any context callback functions to collect the context information
+	 * into edata->context.
+	 *
+	 * Errors occurring in callback functions should go through the regular
+	 * error handling code which should handle any recursive errors, though we
+	 * double-check above, just in case.
+	 */
+	for (econtext = error_context_stack;
+		 econtext != NULL;
+		 econtext = econtext->previous)
+		econtext->callback(econtext->arg);
+
+	/*
+	 * Clean ourselves off the stack, any allocations done should have been
+	 * using edata->assoc_context, which we set up earlier to be the caller's
+	 * context, so we're free to just remove our entry off the stack and
+	 * decrement recursion depth and exit.
+	 */
+	errordata_stack_depth--;
+	recursion_depth--;
+
+	/*
+	 * Return a pointer to the string the caller asked for, which should have
+	 * been allocated in their context.
+	 */
+	return edata->context;
+}
+
+
+/*
+ * Initialization of error output file
+ */
+void
+DebugFileOpen(void)
+{
+	int			fd,
+				istty;
+
+	if (OutputFileName[0])
+	{
+		/*
+		 * A debug-output file name was given.
+		 *
+		 * Make sure we can write the file, and find out if it's a tty.
+		 */
+		if ((fd = open(OutputFileName, O_CREAT | O_APPEND | O_WRONLY,
+					   0666)) < 0)
+			ereport(FATAL,
+					(errcode_for_file_access(),
+					 errmsg("could not open file \"%s\": %m", OutputFileName)));
+		istty = isatty(fd);
+		close(fd);
+
+		/*
+		 * Redirect our stderr to the debug output file.
+		 */
+		if (!freopen(OutputFileName, "a", stderr))
+			ereport(FATAL,
+					(errcode_for_file_access(),
+					 errmsg("could not reopen file \"%s\" as stderr: %m",
+							OutputFileName)));
+
+		/*
+		 * If the file is a tty and we're running under the postmaster, try to
+		 * send stdout there as well (if it isn't a tty then stderr will block
+		 * out stdout, so we may as well let stdout go wherever it was going
+		 * before).
+		 */
+		if (istty && IsUnderPostmaster)
+			if (!freopen(OutputFileName, "a", stdout))
+				ereport(FATAL,
+						(errcode_for_file_access(),
+						 errmsg("could not reopen file \"%s\" as stdout: %m",
+								OutputFileName)));
+	}
+}
+
+
+#ifdef HAVE_SYSLOG
+
+/*
+ * Set or update the parameters for syslog logging
+ */
+void
+set_syslog_parameters(const char *ident, int facility)
+{
+	/*
+	 * guc.c is likely to call us repeatedly with same parameters, so don't
+	 * thrash the syslog connection unnecessarily.  Also, we do not re-open
+	 * the connection until needed, since this routine will get called whether
+	 * or not Log_destination actually mentions syslog.
+	 *
+	 * Note that we make our own copy of the ident string rather than relying
+	 * on guc.c's.  This may be overly paranoid, but it ensures that we cannot
+	 * accidentally free a string that syslog is still using.
+	 */
+	if (syslog_ident == NULL || strcmp(syslog_ident, ident) != 0 ||
+		syslog_facility != facility)
+	{
+		if (openlog_done)
+		{
+			closelog();
+			openlog_done = false;
+		}
+		if (syslog_ident)
+			free(syslog_ident);
+		syslog_ident = strdup(ident);
+		/* if the strdup fails, we will cope in write_syslog() */
+		syslog_facility = facility;
+	}
+}
+
+
+/*
+ * Write a message line to syslog
+ */
+static void
+write_syslog(int level, const char *line)
+{
+	static unsigned long seq = 0;
+
+	int			len;
+	const char *nlpos;
+
+	/* Open syslog connection if not done yet */
+	if (!openlog_done)
+	{
+		openlog(syslog_ident ? syslog_ident : "postgres",
+				LOG_PID | LOG_NDELAY | LOG_NOWAIT,
+				syslog_facility);
+		openlog_done = true;
+	}
+
+	/*
+	 * We add a sequence number to each log message to suppress "same"
+	 * messages.
+	 */
+	seq++;
+
+	/*
+	 * Our problem here is that many syslog implementations don't handle long
+	 * messages in an acceptable manner. While this function doesn't help that
+	 * fact, it does work around by splitting up messages into smaller pieces.
+	 *
+	 * We divide into multiple syslog() calls if message is too long or if the
+	 * message contains embedded newline(s).
+	 */
+	len = strlen(line);
+	nlpos = strchr(line, '\n');
+	if (syslog_split_messages && (len > PG_SYSLOG_LIMIT || nlpos != NULL))
+	{
+		int			chunk_nr = 0;
+
+		while (len > 0)
+		{
+			char		buf[PG_SYSLOG_LIMIT + 1];
+			int			buflen;
+			int			i;
+
+			/* if we start at a newline, move ahead one char */
+			if (line[0] == '\n')
+			{
+				line++;
+				len--;
+				/* we need to recompute the next newline's position, too */
+				nlpos = strchr(line, '\n');
+				continue;
+			}
+
+			/* copy one line, or as much as will fit, to buf */
+			if (nlpos != NULL)
+				buflen = nlpos - line;
+			else
+				buflen = len;
+			buflen = Min(buflen, PG_SYSLOG_LIMIT);
+			memcpy(buf, line, buflen);
+			buf[buflen] = '\0';
+
+			/* trim to multibyte letter boundary */
+			buflen = pg_mbcliplen(buf, buflen, buflen);
+			if (buflen <= 0)
+				return;
+			buf[buflen] = '\0';
+
+			/* already word boundary? */
+			if (line[buflen] != '\0' &&
+				!isspace((unsigned char) line[buflen]))
+			{
+				/* try to divide at word boundary */
+				i = buflen - 1;
+				while (i > 0 && !isspace((unsigned char) buf[i]))
+					i--;
+
+				if (i > 0)		/* else couldn't divide word boundary */
+				{
+					buflen = i;
+					buf[i] = '\0';
+				}
+			}
+
+			chunk_nr++;
+
+			if (syslog_sequence_numbers)
+				syslog(level, "[%lu-%d] %s", seq, chunk_nr, buf);
+			else
+				syslog(level, "[%d] %s", chunk_nr, buf);
+
+			line += buflen;
+			len -= buflen;
+		}
+	}
+	else
+	{
+		/* message short enough */
+		if (syslog_sequence_numbers)
+			syslog(level, "[%lu] %s", seq, line);
+		else
+			syslog(level, "%s", line);
+	}
+}
+#endif							/* HAVE_SYSLOG */
+
+#ifdef WIN32
+/*
+ * Get the PostgreSQL equivalent of the Windows ANSI code page.  "ANSI" system
+ * interfaces (e.g. CreateFileA()) expect string arguments in this encoding.
+ * Every process in a given system will find the same value at all times.
+ */
+static int
+GetACPEncoding(void)
+{
+	static int	encoding = -2;
+
+	if (encoding == -2)
+		encoding = pg_codepage_to_encoding(GetACP());
+
+	return encoding;
+}
+
+/*
+ * Write a message line to the windows event log
+ */
+static void
+write_eventlog(int level, const char *line, int len)
+{
+	WCHAR	   *utf16;
+	int			eventlevel = EVENTLOG_ERROR_TYPE;
+	static HANDLE evtHandle = INVALID_HANDLE_VALUE;
+
+	if (evtHandle == INVALID_HANDLE_VALUE)
+	{
+		evtHandle = RegisterEventSource(NULL,
+										event_source ? event_source : DEFAULT_EVENT_SOURCE);
+		if (evtHandle == NULL)
+		{
+			evtHandle = INVALID_HANDLE_VALUE;
+			return;
+		}
+	}
+
+	switch (level)
+	{
+		case DEBUG5:
+		case DEBUG4:
+		case DEBUG3:
+		case DEBUG2:
+		case DEBUG1:
+		case LOG:
+		case LOG_SERVER_ONLY:
+		case INFO:
+		case NOTICE:
+			eventlevel = EVENTLOG_INFORMATION_TYPE;
+			break;
+		case WARNING:
+		case WARNING_CLIENT_ONLY:
+			eventlevel = EVENTLOG_WARNING_TYPE;
+			break;
+		case ERROR:
+		case FATAL:
+		case PANIC:
+		default:
+			eventlevel = EVENTLOG_ERROR_TYPE;
+			break;
+	}
+
+	/*
+	 * If message character encoding matches the encoding expected by
+	 * ReportEventA(), call it to avoid the hazards of conversion.  Otherwise,
+	 * try to convert the message to UTF16 and write it with ReportEventW().
+	 * Fall back on ReportEventA() if conversion failed.
+	 *
+	 * Since we palloc the structure required for conversion, also fall
+	 * through to writing unconverted if we have not yet set up
+	 * CurrentMemoryContext.
+	 *
+	 * Also verify that we are not on our way into error recursion trouble due
+	 * to error messages thrown deep inside pgwin32_message_to_UTF16().
+	 */
+	if (!in_error_recursion_trouble() &&
+		CurrentMemoryContext != NULL &&
+		GetMessageEncoding() != GetACPEncoding())
+	{
+		utf16 = pgwin32_message_to_UTF16(line, len, NULL);
+		if (utf16)
+		{
+			ReportEventW(evtHandle,
+						 eventlevel,
+						 0,
+						 0,		/* All events are Id 0 */
+						 NULL,
+						 1,
+						 0,
+						 (LPCWSTR *) &utf16,
+						 NULL);
+			/* XXX Try ReportEventA() when ReportEventW() fails? */
+
+			pfree(utf16);
+			return;
+		}
+	}
+	ReportEventA(evtHandle,
+				 eventlevel,
+				 0,
+				 0,				/* All events are Id 0 */
+				 NULL,
+				 1,
+				 0,
+				 &line,
+				 NULL);
+}
+#endif							/* WIN32 */
+
+static void
+write_console(const char *line, int len)
+{
+	int			rc;
+
+#ifdef WIN32
+
+	/*
+	 * Try to convert the message to UTF16 and write it with WriteConsoleW().
+	 * Fall back on write() if anything fails.
+	 *
+	 * In contrast to write_eventlog(), don't skip straight to write() based
+	 * on the applicable encodings.  Unlike WriteConsoleW(), write() depends
+	 * on the suitability of the console output code page.  Since we put
+	 * stderr into binary mode in SubPostmasterMain(), write() skips the
+	 * necessary translation anyway.
+	 *
+	 * WriteConsoleW() will fail if stderr is redirected, so just fall through
+	 * to writing unconverted to the logfile in this case.
+	 *
+	 * Since we palloc the structure required for conversion, also fall
+	 * through to writing unconverted if we have not yet set up
+	 * CurrentMemoryContext.
+	 */
+	if (!in_error_recursion_trouble() &&
+		!redirection_done &&
+		CurrentMemoryContext != NULL)
+	{
+		WCHAR	   *utf16;
+		int			utf16len;
+
+		utf16 = pgwin32_message_to_UTF16(line, len, &utf16len);
+		if (utf16 != NULL)
+		{
+			HANDLE		stdHandle;
+			DWORD		written;
+
+			stdHandle = GetStdHandle(STD_ERROR_HANDLE);
+			if (WriteConsoleW(stdHandle, utf16, utf16len, &written, NULL))
+			{
+				pfree(utf16);
+				return;
+			}
+
+			/*
+			 * In case WriteConsoleW() failed, fall back to writing the
+			 * message unconverted.
+			 */
+			pfree(utf16);
+		}
+	}
+#else
+
+	/*
+	 * Conversion on non-win32 platforms is not implemented yet. It requires
+	 * non-throw version of pg_do_encoding_conversion(), that converts
+	 * unconvertible characters to '?' without errors.
+	 *
+	 * XXX: We have a no-throw version now. It doesn't convert to '?' though.
+	 */
+#endif
+
+	/*
+	 * We ignore any error from write() here.  We have no useful way to report
+	 * it ... certainly whining on stderr isn't likely to be productive.
+	 */
+	rc = write(fileno(stderr), line, len);
+	(void) rc;
+}
+
+/*
+ * get_formatted_log_time -- compute and get the log timestamp.
+ *
+ * The timestamp is computed if not set yet, so as it is kept consistent
+ * among all the log destinations that require it to be consistent.  Note
+ * that the computed timestamp is returned in a static buffer, not
+ * palloc()'d.
+ */
+char *
+get_formatted_log_time(void)
+{
+	pg_time_t	stamp_time;
+	char		msbuf[13];
+
+	/* leave if already computed */
+	if (formatted_log_time[0] != '\0')
+		return formatted_log_time;
+
+	if (!saved_timeval_set)
+	{
+		gettimeofday(&saved_timeval, NULL);
+		saved_timeval_set = true;
+	}
+
+	stamp_time = (pg_time_t) saved_timeval.tv_sec;
+
+	/*
+	 * Note: we expect that guc.c will ensure that log_timezone is set up (at
+	 * least with a minimal GMT value) before Log_line_prefix can become
+	 * nonempty or CSV mode can be selected.
+	 */
+	pg_strftime(formatted_log_time, FORMATTED_TS_LEN,
+	/* leave room for milliseconds... */
+				"%Y-%m-%d %H:%M:%S     %Z",
+				pg_localtime(&stamp_time, log_timezone));
+
+	/* 'paste' milliseconds into place... */
+	sprintf(msbuf, ".%03d", (int) (saved_timeval.tv_usec / 1000));
+	memcpy(formatted_log_time + 19, msbuf, 4);
+
+	return formatted_log_time;
+}
+
+/*
+ * reset_formatted_start_time -- reset the start timestamp
+ */
+void
+reset_formatted_start_time(void)
+{
+	formatted_start_time[0] = '\0';
+}
+
+/*
+ * get_formatted_start_time -- compute and get the start timestamp.
+ *
+ * The timestamp is computed if not set yet.  Note that the computed
+ * timestamp is returned in a static buffer, not palloc()'d.
+ */
+char *
+get_formatted_start_time(void)
+{
+	pg_time_t	stamp_time = (pg_time_t) MyStartTime;
+
+	/* leave if already computed */
+	if (formatted_start_time[0] != '\0')
+		return formatted_start_time;
+
+	/*
+	 * Note: we expect that guc.c will ensure that log_timezone is set up (at
+	 * least with a minimal GMT value) before Log_line_prefix can become
+	 * nonempty or CSV mode can be selected.
+	 */
+	pg_strftime(formatted_start_time, FORMATTED_TS_LEN,
+				"%Y-%m-%d %H:%M:%S %Z",
+				pg_localtime(&stamp_time, log_timezone));
+
+	return formatted_start_time;
+}
+
+/*
+ * check_log_of_query -- check if a query can be logged
+ */
+bool
+check_log_of_query(ErrorData *edata)
+{
+	/* log required? */
+	if (!is_log_level_output(edata->elevel, log_min_error_statement))
+		return false;
+
+	/* query log wanted? */
+	if (edata->hide_stmt)
+		return false;
+
+	/* query string available? */
+	if (debug_query_string == NULL)
+		return false;
+
+	return true;
+}
+
+/*
+ * get_backend_type_for_log -- backend type for log entries
+ *
+ * Returns a pointer to a static buffer, not palloc()'d.
+ */
+const char *
+get_backend_type_for_log(void)
+{
+	const char *backend_type_str;
+
+	if (MyProcPid == PostmasterPid)
+		backend_type_str = "postmaster";
+	else if (MyBackendType == B_BG_WORKER)
+		backend_type_str = MyBgworkerEntry->bgw_type;
+	else
+		backend_type_str = GetBackendTypeDesc(MyBackendType);
+
+	return backend_type_str;
+}
+
+/*
+ * process_log_prefix_padding --- helper function for processing the format
+ * string in log_line_prefix
+ *
+ * Note: This function returns NULL if it finds something which
+ * it deems invalid in the format string.
+ */
+static const char *
+process_log_prefix_padding(const char *p, int *ppadding)
+{
+	int			paddingsign = 1;
+	int			padding = 0;
+
+	if (*p == '-')
+	{
+		p++;
+
+		if (*p == '\0')			/* Did the buf end in %- ? */
+			return NULL;
+		paddingsign = -1;
+	}
+
+	/* generate an int version of the numerical string */
+	while (*p >= '0' && *p <= '9')
+		padding = padding * 10 + (*p++ - '0');
+
+	/* format is invalid if it ends with the padding number */
+	if (*p == '\0')
+		return NULL;
+
+	padding *= paddingsign;
+	*ppadding = padding;
+	return p;
+}
+
+/*
+ * Format tag info for log lines; append to the provided buffer.
+ */
+static void
+log_line_prefix(StringInfo buf, ErrorData *edata)
+{
+	/* static counter for line numbers */
+	static long log_line_number = 0;
+
+	/* has counter been reset in current process? */
+	static int	log_my_pid = 0;
+	int			padding;
+	const char *p;
+
+	/*
+	 * This is one of the few places where we'd rather not inherit a static
+	 * variable's value from the postmaster.  But since we will, reset it when
+	 * MyProcPid changes. MyStartTime also changes when MyProcPid does, so
+	 * reset the formatted start timestamp too.
+	 */
+	if (log_my_pid != MyProcPid)
+	{
+		log_line_number = 0;
+		log_my_pid = MyProcPid;
+		reset_formatted_start_time();
+	}
+	log_line_number++;
+
+	if (Log_line_prefix == NULL)
+		return;					/* in case guc hasn't run yet */
+
+	for (p = Log_line_prefix; *p != '\0'; p++)
+	{
+		if (*p != '%')
+		{
+			/* literal char, just copy */
+			appendStringInfoChar(buf, *p);
+			continue;
+		}
+
+		/* must be a '%', so skip to the next char */
+		p++;
+		if (*p == '\0')
+			break;				/* format error - ignore it */
+		else if (*p == '%')
+		{
+			/* string contains %% */
+			appendStringInfoChar(buf, '%');
+			continue;
+		}
+
+
+		/*
+		 * Process any formatting which may exist after the '%'.  Note that
+		 * process_log_prefix_padding moves p past the padding number if it
+		 * exists.
+		 *
+		 * Note: Since only '-', '0' to '9' are valid formatting characters we
+		 * can do a quick check here to pre-check for formatting. If the char
+		 * is not formatting then we can skip a useless function call.
+		 *
+		 * Further note: At least on some platforms, passing %*s rather than
+		 * %s to appendStringInfo() is substantially slower, so many of the
+		 * cases below avoid doing that unless non-zero padding is in fact
+		 * specified.
+		 */
+		if (*p > '9')
+			padding = 0;
+		else if ((p = process_log_prefix_padding(p, &padding)) == NULL)
+			break;
+
+		/* process the option */
+		switch (*p)
+		{
+			case 'a':
+				if (MyProcPort)
+				{
+					const char *appname = application_name;
+
+					if (appname == NULL || *appname == '\0')
+						appname = _("[unknown]");
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, appname);
+					else
+						appendStringInfoString(buf, appname);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+
+				break;
+			case 'b':
+				{
+					const char *backend_type_str = get_backend_type_for_log();
+
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, backend_type_str);
+					else
+						appendStringInfoString(buf, backend_type_str);
+					break;
+				}
+			case 'u':
+				if (MyProcPort)
+				{
+					const char *username = MyProcPort->user_name;
+
+					if (username == NULL || *username == '\0')
+						username = _("[unknown]");
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, username);
+					else
+						appendStringInfoString(buf, username);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+			case 'd':
+				if (MyProcPort)
+				{
+					const char *dbname = MyProcPort->database_name;
+
+					if (dbname == NULL || *dbname == '\0')
+						dbname = _("[unknown]");
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, dbname);
+					else
+						appendStringInfoString(buf, dbname);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+			case 'c':
+				if (padding != 0)
+				{
+					char		strfbuf[128];
+
+					snprintf(strfbuf, sizeof(strfbuf) - 1, "%lx.%x",
+							 (long) (MyStartTime), MyProcPid);
+					appendStringInfo(buf, "%*s", padding, strfbuf);
+				}
+				else
+					appendStringInfo(buf, "%lx.%x", (long) (MyStartTime), MyProcPid);
+				break;
+			case 'p':
+				if (padding != 0)
+					appendStringInfo(buf, "%*d", padding, MyProcPid);
+				else
+					appendStringInfo(buf, "%d", MyProcPid);
+				break;
+
+			case 'P':
+				if (MyProc)
+				{
+					PGPROC	   *leader = MyProc->lockGroupLeader;
+
+					/*
+					 * Show the leader only for active parallel workers. This
+					 * leaves out the leader of a parallel group.
+					 */
+					if (leader == NULL || leader->pid == MyProcPid)
+						appendStringInfoSpaces(buf,
+											   padding > 0 ? padding : -padding);
+					else if (padding != 0)
+						appendStringInfo(buf, "%*d", padding, leader->pid);
+					else
+						appendStringInfo(buf, "%d", leader->pid);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+
+			case 'l':
+				if (padding != 0)
+					appendStringInfo(buf, "%*ld", padding, log_line_number);
+				else
+					appendStringInfo(buf, "%ld", log_line_number);
+				break;
+			case 'm':
+				/* force a log timestamp reset */
+				formatted_log_time[0] = '\0';
+				(void) get_formatted_log_time();
+
+				if (padding != 0)
+					appendStringInfo(buf, "%*s", padding, formatted_log_time);
+				else
+					appendStringInfoString(buf, formatted_log_time);
+				break;
+			case 't':
+				{
+					pg_time_t	stamp_time = (pg_time_t) time(NULL);
+					char		strfbuf[128];
+
+					pg_strftime(strfbuf, sizeof(strfbuf),
+								"%Y-%m-%d %H:%M:%S %Z",
+								pg_localtime(&stamp_time, log_timezone));
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, strfbuf);
+					else
+						appendStringInfoString(buf, strfbuf);
+				}
+				break;
+			case 'n':
+				{
+					char		strfbuf[128];
+
+					if (!saved_timeval_set)
+					{
+						gettimeofday(&saved_timeval, NULL);
+						saved_timeval_set = true;
+					}
+
+					snprintf(strfbuf, sizeof(strfbuf), "%ld.%03d",
+							 (long) saved_timeval.tv_sec,
+							 (int) (saved_timeval.tv_usec / 1000));
+
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, strfbuf);
+					else
+						appendStringInfoString(buf, strfbuf);
+				}
+				break;
+			case 's':
+				{
+					char	   *start_time = get_formatted_start_time();
+
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, start_time);
+					else
+						appendStringInfoString(buf, start_time);
+				}
+				break;
+			case 'i':
+				if (MyProcPort)
+				{
+					const char *psdisp;
+					int			displen;
+
+					psdisp = get_ps_display(&displen);
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, psdisp);
+					else
+						appendBinaryStringInfo(buf, psdisp, displen);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+			case 'r':
+				if (MyProcPort && MyProcPort->remote_host)
+				{
+					if (padding != 0)
+					{
+						if (MyProcPort->remote_port && MyProcPort->remote_port[0] != '\0')
+						{
+							/*
+							 * This option is slightly special as the port
+							 * number may be appended onto the end. Here we
+							 * need to build 1 string which contains the
+							 * remote_host and optionally the remote_port (if
+							 * set) so we can properly align the string.
+							 */
+
+							char	   *hostport;
+
+							hostport = psprintf("%s(%s)", MyProcPort->remote_host, MyProcPort->remote_port);
+							appendStringInfo(buf, "%*s", padding, hostport);
+							pfree(hostport);
+						}
+						else
+							appendStringInfo(buf, "%*s", padding, MyProcPort->remote_host);
+					}
+					else
+					{
+						/* padding is 0, so we don't need a temp buffer */
+						appendStringInfoString(buf, MyProcPort->remote_host);
+						if (MyProcPort->remote_port &&
+							MyProcPort->remote_port[0] != '\0')
+							appendStringInfo(buf, "(%s)",
+											 MyProcPort->remote_port);
+					}
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+			case 'h':
+				if (MyProcPort && MyProcPort->remote_host)
+				{
+					if (padding != 0)
+						appendStringInfo(buf, "%*s", padding, MyProcPort->remote_host);
+					else
+						appendStringInfoString(buf, MyProcPort->remote_host);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+			case 'q':
+				/* in postmaster and friends, stop if %q is seen */
+				/* in a backend, just ignore */
+				if (MyProcPort == NULL)
+					return;
+				break;
+			case 'v':
+				/* keep VXID format in sync with lockfuncs.c */
+				if (MyProc != NULL && MyProc->backendId != InvalidBackendId)
+				{
+					if (padding != 0)
+					{
+						char		strfbuf[128];
+
+						snprintf(strfbuf, sizeof(strfbuf) - 1, "%d/%u",
+								 MyProc->backendId, MyProc->lxid);
+						appendStringInfo(buf, "%*s", padding, strfbuf);
+					}
+					else
+						appendStringInfo(buf, "%d/%u", MyProc->backendId, MyProc->lxid);
+				}
+				else if (padding != 0)
+					appendStringInfoSpaces(buf,
+										   padding > 0 ? padding : -padding);
+				break;
+			case 'x':
+				if (padding != 0)
+					appendStringInfo(buf, "%*u", padding, GetTopTransactionIdIfAny());
+				else
+					appendStringInfo(buf, "%u", GetTopTransactionIdIfAny());
+				break;
+			case 'e':
+				if (padding != 0)
+					appendStringInfo(buf, "%*s", padding, unpack_sql_state(edata->sqlerrcode));
+				else
+					appendStringInfoString(buf, unpack_sql_state(edata->sqlerrcode));
+				break;
+			case 'Q':
+				if (padding != 0)
+					appendStringInfo(buf, "%*lld", padding,
+									 (long long) pgstat_get_my_query_id());
+				else
+					appendStringInfo(buf, "%lld",
+									 (long long) pgstat_get_my_query_id());
+				break;
+			default:
+				/* format error - ignore it */
+				break;
+		}
+	}
+}
+
+/*
+ * Unpack MAKE_SQLSTATE code. Note that this returns a pointer to a
+ * static buffer.
+ */
+char *
+unpack_sql_state(int sql_state)
+{
+	static char buf[12];
+	int			i;
+
+	for (i = 0; i < 5; i++)
+	{
+		buf[i] = PGUNSIXBIT(sql_state);
+		sql_state >>= 6;
+	}
+
+	buf[i] = '\0';
+	return buf;
+}
+
+
+/*
+ * Write error report to server's log
+ */
+static void
+send_message_to_server_log(ErrorData *edata)
+{
+	StringInfoData buf;
+	bool		fallback_to_stderr = false;
+
+	initStringInfo(&buf);
+
+	saved_timeval_set = false;
+	formatted_log_time[0] = '\0';
+
+	log_line_prefix(&buf, edata);
+	appendStringInfo(&buf, "%s:  ", _(error_severity(edata->elevel)));
+
+	if (Log_error_verbosity >= PGERROR_VERBOSE)
+		appendStringInfo(&buf, "%s: ", unpack_sql_state(edata->sqlerrcode));
+
+	if (edata->message)
+		append_with_tabs(&buf, edata->message);
+	else
+		append_with_tabs(&buf, _("missing error text"));
+
+	if (edata->cursorpos > 0)
+		appendStringInfo(&buf, _(" at character %d"),
+						 edata->cursorpos);
+	else if (edata->internalpos > 0)
+		appendStringInfo(&buf, _(" at character %d"),
+						 edata->internalpos);
+
+	appendStringInfoChar(&buf, '\n');
+
+	if (Log_error_verbosity >= PGERROR_DEFAULT)
+	{
+		if (edata->detail_log)
+		{
+			log_line_prefix(&buf, edata);
+			appendStringInfoString(&buf, _("DETAIL:  "));
+			append_with_tabs(&buf, edata->detail_log);
+			appendStringInfoChar(&buf, '\n');
+		}
+		else if (edata->detail)
+		{
+			log_line_prefix(&buf, edata);
+			appendStringInfoString(&buf, _("DETAIL:  "));
+			append_with_tabs(&buf, edata->detail);
+			appendStringInfoChar(&buf, '\n');
+		}
+		if (edata->hint)
+		{
+			log_line_prefix(&buf, edata);
+			appendStringInfoString(&buf, _("HINT:  "));
+			append_with_tabs(&buf, edata->hint);
+			appendStringInfoChar(&buf, '\n');
+		}
+		if (edata->internalquery)
+		{
+			log_line_prefix(&buf, edata);
+			appendStringInfoString(&buf, _("QUERY:  "));
+			append_with_tabs(&buf, edata->internalquery);
+			appendStringInfoChar(&buf, '\n');
+		}
+		if (edata->context && !edata->hide_ctx)
+		{
+			log_line_prefix(&buf, edata);
+			appendStringInfoString(&buf, _("CONTEXT:  "));
+			append_with_tabs(&buf, edata->context);
+			appendStringInfoChar(&buf, '\n');
+		}
+		if (Log_error_verbosity >= PGERROR_VERBOSE)
+		{
+			/* assume no newlines in funcname or filename... */
+			if (edata->funcname && edata->filename)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("LOCATION:  %s, %s:%d\n"),
+								 edata->funcname, edata->filename,
+								 edata->lineno);
+			}
+			else if (edata->filename)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("LOCATION:  %s:%d\n"),
+								 edata->filename, edata->lineno);
+			}
+		}
+		if (edata->backtrace)
+		{
+			log_line_prefix(&buf, edata);
+			appendStringInfoString(&buf, _("BACKTRACE:  "));
+			append_with_tabs(&buf, edata->backtrace);
+			appendStringInfoChar(&buf, '\n');
+		}
+	}
+
+	/*
+	 * If the user wants the query that generated this error logged, do it.
+	 */
+	if (check_log_of_query(edata))
+	{
+		log_line_prefix(&buf, edata);
+		appendStringInfoString(&buf, _("STATEMENT:  "));
+		append_with_tabs(&buf, debug_query_string);
+		appendStringInfoChar(&buf, '\n');
+	}
+
+#ifdef HAVE_SYSLOG
+	/* Write to syslog, if enabled */
+	if (Log_destination & LOG_DESTINATION_SYSLOG)
+	{
+		int			syslog_level;
+
+		switch (edata->elevel)
+		{
+			case DEBUG5:
+			case DEBUG4:
+			case DEBUG3:
+			case DEBUG2:
+			case DEBUG1:
+				syslog_level = LOG_DEBUG;
+				break;
+			case LOG:
+			case LOG_SERVER_ONLY:
+			case INFO:
+				syslog_level = LOG_INFO;
+				break;
+			case NOTICE:
+			case WARNING:
+			case WARNING_CLIENT_ONLY:
+				syslog_level = LOG_NOTICE;
+				break;
+			case ERROR:
+				syslog_level = LOG_WARNING;
+				break;
+			case FATAL:
+				syslog_level = LOG_ERR;
+				break;
+			case PANIC:
+			default:
+				syslog_level = LOG_CRIT;
+				break;
+		}
+
+		write_syslog(syslog_level, buf.data);
+	}
+#endif							/* HAVE_SYSLOG */
+
+#ifdef WIN32
+	/* Write to eventlog, if enabled */
+	if (Log_destination & LOG_DESTINATION_EVENTLOG)
+	{
+		write_eventlog(edata->elevel, buf.data, buf.len);
+	}
+#endif							/* WIN32 */
+
+	/* Write to csvlog, if enabled */
+	if (Log_destination & LOG_DESTINATION_CSVLOG)
+	{
+		/*
+		 * Send CSV data if it's safe to do so (syslogger doesn't need the
+		 * pipe).  If this is not possible, fallback to an entry written to
+		 * stderr.
+		 */
+		if (redirection_done || MyBackendType == B_LOGGER)
+			write_csvlog(edata);
+		else
+			fallback_to_stderr = true;
+	}
+
+	/* Write to JSON log, if enabled */
+	if (Log_destination & LOG_DESTINATION_JSONLOG)
+	{
+		/*
+		 * Send JSON data if it's safe to do so (syslogger doesn't need the
+		 * pipe).  If this is not possible, fallback to an entry written to
+		 * stderr.
+		 */
+		if (redirection_done || MyBackendType == B_LOGGER)
+		{
+			write_jsonlog(edata);
+		}
+		else
+			fallback_to_stderr = true;
+	}
+
+	/*
+	 * Write to stderr, if enabled or if required because of a previous
+	 * limitation.
+	 */
+	if ((Log_destination & LOG_DESTINATION_STDERR) ||
+		whereToSendOutput == DestDebug ||
+		fallback_to_stderr)
+	{
+		/*
+		 * Use the chunking protocol if we know the syslogger should be
+		 * catching stderr output, and we are not ourselves the syslogger.
+		 * Otherwise, just do a vanilla write to stderr.
+		 */
+		if (redirection_done && MyBackendType != B_LOGGER)
+			write_pipe_chunks(buf.data, buf.len, LOG_DESTINATION_STDERR);
+#ifdef WIN32
+
+		/*
+		 * In a win32 service environment, there is no usable stderr. Capture
+		 * anything going there and write it to the eventlog instead.
+		 *
+		 * If stderr redirection is active, it was OK to write to stderr above
+		 * because that's really a pipe to the syslogger process.
+		 */
+		else if (pgwin32_is_service())
+			write_eventlog(edata->elevel, buf.data, buf.len);
+#endif
+		else
+			write_console(buf.data, buf.len);
+	}
+
+	/* If in the syslogger process, try to write messages direct to file */
+	if (MyBackendType == B_LOGGER)
+		write_syslogger_file(buf.data, buf.len, LOG_DESTINATION_STDERR);
+
+	/* No more need of the message formatted for stderr */
+	pfree(buf.data);
+}
+
+/*
+ * Send data to the syslogger using the chunked protocol
+ *
+ * Note: when there are multiple backends writing into the syslogger pipe,
+ * it's critical that each write go into the pipe indivisibly, and not
+ * get interleaved with data from other processes.  Fortunately, the POSIX
+ * spec requires that writes to pipes be atomic so long as they are not
+ * more than PIPE_BUF bytes long.  So we divide long messages into chunks
+ * that are no more than that length, and send one chunk per write() call.
+ * The collector process knows how to reassemble the chunks.
+ *
+ * Because of the atomic write requirement, there are only two possible
+ * results from write() here: -1 for failure, or the requested number of
+ * bytes.  There is not really anything we can do about a failure; retry would
+ * probably be an infinite loop, and we can't even report the error usefully.
+ * (There is noplace else we could send it!)  So we might as well just ignore
+ * the result from write().  However, on some platforms you get a compiler
+ * warning from ignoring write()'s result, so do a little dance with casting
+ * rc to void to shut up the compiler.
+ */
+void
+write_pipe_chunks(char *data, int len, int dest)
+{
+	PipeProtoChunk p;
+	int			fd = fileno(stderr);
+	int			rc;
+
+	Assert(len > 0);
+
+	p.proto.nuls[0] = p.proto.nuls[1] = '\0';
+	p.proto.pid = MyProcPid;
+	p.proto.flags = 0;
+	if (dest == LOG_DESTINATION_STDERR)
+		p.proto.flags |= PIPE_PROTO_DEST_STDERR;
+	else if (dest == LOG_DESTINATION_CSVLOG)
+		p.proto.flags |= PIPE_PROTO_DEST_CSVLOG;
+	else if (dest == LOG_DESTINATION_JSONLOG)
+		p.proto.flags |= PIPE_PROTO_DEST_JSONLOG;
+
+	/* write all but the last chunk */
+	while (len > PIPE_MAX_PAYLOAD)
+	{
+		/* no need to set PIPE_PROTO_IS_LAST yet */
+		p.proto.len = PIPE_MAX_PAYLOAD;
+		memcpy(p.proto.data, data, PIPE_MAX_PAYLOAD);
+		rc = write(fd, &p, PIPE_HEADER_SIZE + PIPE_MAX_PAYLOAD);
+		(void) rc;
+		data += PIPE_MAX_PAYLOAD;
+		len -= PIPE_MAX_PAYLOAD;
+	}
+
+	/* write the last chunk */
+	p.proto.flags |= PIPE_PROTO_IS_LAST;
+	p.proto.len = len;
+	memcpy(p.proto.data, data, len);
+	rc = write(fd, &p, PIPE_HEADER_SIZE + len);
+	(void) rc;
+}
+
+
+/*
+ * Append a text string to the error report being built for the client.
+ *
+ * This is ordinarily identical to pq_sendstring(), but if we are in
+ * error recursion trouble we skip encoding conversion, because of the
+ * possibility that the problem is a failure in the encoding conversion
+ * subsystem itself.  Code elsewhere should ensure that the passed-in
+ * strings will be plain 7-bit ASCII, and thus not in need of conversion,
+ * in such cases.  (In particular, we disable localization of error messages
+ * to help ensure that's true.)
+ */
+static void
+err_sendstring(StringInfo buf, const char *str)
+{
+	if (in_error_recursion_trouble())
+		pq_send_ascii_string(buf, str);
+	else
+		pq_sendstring(buf, str);
+}
+
+/*
+ * Write error report to client
+ */
+static void
+send_message_to_frontend(ErrorData *edata)
+{
+	StringInfoData msgbuf;
+
+	/*
+	 * We no longer support pre-3.0 FE/BE protocol, except here.  If a client
+	 * tries to connect using an older protocol version, it's nice to send the
+	 * "protocol version not supported" error in a format the client
+	 * understands.  If protocol hasn't been set yet, early in backend
+	 * startup, assume modern protocol.
+	 */
+	if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3 || FrontendProtocol == 0)
+	{
+		/* New style with separate fields */
+		const char *sev;
+		char		tbuf[12];
+
+		/* 'N' (Notice) is for nonfatal conditions, 'E' is for errors */
+		pq_beginmessage(&msgbuf, (edata->elevel < ERROR) ? 'N' : 'E');
+
+		sev = error_severity(edata->elevel);
+		pq_sendbyte(&msgbuf, PG_DIAG_SEVERITY);
+		err_sendstring(&msgbuf, _(sev));
+		pq_sendbyte(&msgbuf, PG_DIAG_SEVERITY_NONLOCALIZED);
+		err_sendstring(&msgbuf, sev);
+
+		pq_sendbyte(&msgbuf, PG_DIAG_SQLSTATE);
+		err_sendstring(&msgbuf, unpack_sql_state(edata->sqlerrcode));
+
+		/* M field is required per protocol, so always send something */
+		pq_sendbyte(&msgbuf, PG_DIAG_MESSAGE_PRIMARY);
+		if (edata->message)
+			err_sendstring(&msgbuf, edata->message);
+		else
+			err_sendstring(&msgbuf, _("missing error text"));
+
+		if (edata->detail)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_MESSAGE_DETAIL);
+			err_sendstring(&msgbuf, edata->detail);
+		}
+
+		/* detail_log is intentionally not used here */
+
+		if (edata->hint)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_MESSAGE_HINT);
+			err_sendstring(&msgbuf, edata->hint);
+		}
+
+		if (edata->context)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_CONTEXT);
+			err_sendstring(&msgbuf, edata->context);
+		}
+
+		if (edata->schema_name)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_SCHEMA_NAME);
+			err_sendstring(&msgbuf, edata->schema_name);
+		}
+
+		if (edata->table_name)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_TABLE_NAME);
+			err_sendstring(&msgbuf, edata->table_name);
+		}
+
+		if (edata->column_name)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_COLUMN_NAME);
+			err_sendstring(&msgbuf, edata->column_name);
+		}
+
+		if (edata->datatype_name)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_DATATYPE_NAME);
+			err_sendstring(&msgbuf, edata->datatype_name);
+		}
+
+		if (edata->constraint_name)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_CONSTRAINT_NAME);
+			err_sendstring(&msgbuf, edata->constraint_name);
+		}
+
+		if (edata->cursorpos > 0)
+		{
+			snprintf(tbuf, sizeof(tbuf), "%d", edata->cursorpos);
+			pq_sendbyte(&msgbuf, PG_DIAG_STATEMENT_POSITION);
+			err_sendstring(&msgbuf, tbuf);
+		}
+
+		if (edata->internalpos > 0)
+		{
+			snprintf(tbuf, sizeof(tbuf), "%d", edata->internalpos);
+			pq_sendbyte(&msgbuf, PG_DIAG_INTERNAL_POSITION);
+			err_sendstring(&msgbuf, tbuf);
+		}
+
+		if (edata->internalquery)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_INTERNAL_QUERY);
+			err_sendstring(&msgbuf, edata->internalquery);
+		}
+
+		if (edata->filename)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_SOURCE_FILE);
+			err_sendstring(&msgbuf, edata->filename);
+		}
+
+		if (edata->lineno > 0)
+		{
+			snprintf(tbuf, sizeof(tbuf), "%d", edata->lineno);
+			pq_sendbyte(&msgbuf, PG_DIAG_SOURCE_LINE);
+			err_sendstring(&msgbuf, tbuf);
+		}
+
+		if (edata->funcname)
+		{
+			pq_sendbyte(&msgbuf, PG_DIAG_SOURCE_FUNCTION);
+			err_sendstring(&msgbuf, edata->funcname);
+		}
+
+		pq_sendbyte(&msgbuf, '\0'); /* terminator */
+
+		pq_endmessage(&msgbuf);
+	}
+	else
+	{
+		/* Old style --- gin up a backwards-compatible message */
+		StringInfoData buf;
+
+		initStringInfo(&buf);
+
+		appendStringInfo(&buf, "%s:  ", _(error_severity(edata->elevel)));
+
+		if (edata->message)
+			appendStringInfoString(&buf, edata->message);
+		else
+			appendStringInfoString(&buf, _("missing error text"));
+
+		appendStringInfoChar(&buf, '\n');
+
+		/* 'N' (Notice) is for nonfatal conditions, 'E' is for errors */
+		pq_putmessage_v2((edata->elevel < ERROR) ? 'N' : 'E', buf.data, buf.len + 1);
+
+		pfree(buf.data);
+	}
+
+	/*
+	 * This flush is normally not necessary, since postgres.c will flush out
+	 * waiting data when control returns to the main loop. But it seems best
+	 * to leave it here, so that the client has some clue what happened if the
+	 * backend dies before getting back to the main loop ... error/notice
+	 * messages should not be a performance-critical path anyway, so an extra
+	 * flush won't hurt much ...
+	 */
+	pq_flush();
+}
+
+
+/*
+ * Support routines for formatting error messages.
+ */
+
+
+/*
+ * error_severity --- get string representing elevel
+ *
+ * The string is not localized here, but we mark the strings for translation
+ * so that callers can invoke _() on the result.
+ */
+const char *
+error_severity(int elevel)
+{
+	const char *prefix;
+
+	switch (elevel)
+	{
+		case DEBUG1:
+		case DEBUG2:
+		case DEBUG3:
+		case DEBUG4:
+		case DEBUG5:
+			prefix = gettext_noop("DEBUG");
+			break;
+		case LOG:
+		case LOG_SERVER_ONLY:
+			prefix = gettext_noop("LOG");
+			break;
+		case INFO:
+			prefix = gettext_noop("INFO");
+			break;
+		case NOTICE:
+			prefix = gettext_noop("NOTICE");
+			break;
+		case WARNING:
+		case WARNING_CLIENT_ONLY:
+			prefix = gettext_noop("WARNING");
+			break;
+		case ERROR:
+			prefix = gettext_noop("ERROR");
+			break;
+		case FATAL:
+			prefix = gettext_noop("FATAL");
+			break;
+		case PANIC:
+			prefix = gettext_noop("PANIC");
+			break;
+		default:
+			prefix = "???";
+			break;
+	}
+
+	return prefix;
+}
+
+
+/*
+ *	append_with_tabs
+ *
+ *	Append the string to the StringInfo buffer, inserting a tab after any
+ *	newline.
+ */
+static void
+append_with_tabs(StringInfo buf, const char *str)
+{
+	char		ch;
+
+	while ((ch = *str++) != '\0')
+	{
+		appendStringInfoCharMacro(buf, ch);
+		if (ch == '\n')
+			appendStringInfoCharMacro(buf, '\t');
+	}
+}
+
+
+/*
+ * Write errors to stderr (or by equal means when stderr is
+ * not available). Used before ereport/elog can be used
+ * safely (memory context, GUC load etc)
+ */
+void
+write_stderr(const char *fmt,...)
+{
+	va_list		ap;
+
+#ifdef WIN32
+	char		errbuf[2048];	/* Arbitrary size? */
+#endif
+
+	fmt = _(fmt);
+
+	va_start(ap, fmt);
+#ifndef WIN32
+	/* On Unix, we just fprintf to stderr */
+	vfprintf(stderr, fmt, ap);
+	fflush(stderr);
+#else
+	vsnprintf(errbuf, sizeof(errbuf), fmt, ap);
+
+	/*
+	 * On Win32, we print to stderr if running on a console, or write to
+	 * eventlog if running as a service
+	 */
+	if (pgwin32_is_service())	/* Running as a service */
+	{
+		write_eventlog(ERROR, errbuf, strlen(errbuf));
+	}
+	else
+	{
+		/* Not running as service, write to stderr */
+		write_console(errbuf, strlen(errbuf));
+		fflush(stderr);
+	}
+#endif
+	va_end(ap);
+}
+
+
+/*
+ * Write a message to STDERR using only async-signal-safe functions.  This can
+ * be used to safely emit a message from a signal handler.
+ *
+ * TODO: It is likely possible to safely do a limited amount of string
+ * interpolation (e.g., %s and %d), but that is not presently supported.
+ */
+void
+write_stderr_signal_safe(const char *str)
+{
+	int			nwritten = 0;
+	int			ntotal = strlen(str);
+
+	while (nwritten < ntotal)
+	{
+		int			rc;
+
+		rc = write(STDERR_FILENO, str + nwritten, ntotal - nwritten);
+
+		/* Just give up on error.  There isn't much else we can do. */
+		if (rc == -1)
+			return;
+
+		nwritten += rc;
+	}
+}
+
+
+/*
+ * Adjust the level of a recovery-related message per trace_recovery_messages.
+ *
+ * The argument is the default log level of the message, eg, DEBUG2.  (This
+ * should only be applied to DEBUGn log messages, otherwise it's a no-op.)
+ * If the level is >= trace_recovery_messages, we return LOG, causing the
+ * message to be logged unconditionally (for most settings of
+ * log_min_messages).  Otherwise, we return the argument unchanged.
+ * The message will then be shown based on the setting of log_min_messages.
+ *
+ * Intention is to keep this for at least the whole of the 9.0 production
+ * release, so we can more easily diagnose production problems in the field.
+ * It should go away eventually, though, because it's an ugly and
+ * hard-to-explain kluge.
+ */
+int
+trace_recovery(int trace_level)
+{
+	if (trace_level < LOG &&
+		trace_level >= trace_recovery_messages)
+		return LOG;
+
+	return trace_level;
+}