Add --help-config facility to dump information about GUC parameters

without needing a running backend.  Reorder postgresql.conf.sample
to match new layout of runtime.sgml.  This commit re-adds work lost
in Wednesday's crash.

src/include/utils/guc_tables.h

@@ -0,0 +1,178 @@
+/*-------------------------------------------------------------------------
+ *
+ * guc_tables.h
+ *		Declarations of tables used by GUC.
+ *
+ * See src/backend/utils/misc/README for design notes.
+ *
+ * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ *
+ *	  $Id: guc_tables.h,v 1.1 2003/07/04 16:41:22 tgl Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef GUC_TABLES
+#define GUC_TABLES 1
+
+/*
+ * Groupings to help organize all the run-time options for display.
+ *
+ * Keep this in sync with config_group_names[] in guc.c.
+ */
+enum config_group
+{
+	UNGROUPED,
+	CONN_AUTH,
+	CONN_AUTH_SETTINGS,
+	CONN_AUTH_SECURITY,
+	RESOURCES,
+	RESOURCES_MEM,
+	RESOURCES_FSM,
+	RESOURCES_KERNEL,
+	WAL,
+	WAL_SETTINGS,
+	WAL_CHECKPOINTS,
+	QUERY_TUNING,
+	QUERY_TUNING_METHOD,
+	QUERY_TUNING_COST,
+	QUERY_TUNING_GEQO,
+	QUERY_TUNING_OTHER,
+	LOGGING,
+	LOGGING_SYSLOG,
+	LOGGING_WHEN,
+	LOGGING_WHAT,
+	STATS,
+	STATS_MONITORING,
+	STATS_COLLECTOR,
+	CLIENT_CONN,
+	CLIENT_CONN_STATEMENT,
+	CLIENT_CONN_LOCALE,
+	CLIENT_CONN_OTHER,
+	LOCK_MANAGEMENT,
+	COMPAT_OPTIONS,
+	COMPAT_OPTIONS_PREVIOUS,
+	COMPAT_OPTIONS_CLIENT,
+	DEVELOPER_OPTIONS
+};
+
+
+/*
+ * GUC supports these types of variables:
+ */
+enum config_type
+{
+	PGC_BOOL,
+	PGC_INT,
+	PGC_REAL,
+	PGC_STRING
+};
+
+/*
+ * Generic fields applicable to all types of variables
+ *
+ * The short description should be less than 80 chars in length. Some
+ * applications may use the long description as well, and will append 
+ * it to the short description. (separated by a newline or '. ') 
+ */
+struct config_generic
+{
+	/* constant fields, must be set correctly in initial value: */
+	const char *name;			/* name of variable - MUST BE FIRST */
+	GucContext	context;		/* context required to set the variable */
+	enum config_group group;    /* to help organize variables by function */
+	const char *short_desc;     /* short desc. of this variable's purpose */
+	const char *long_desc;      /* long desc. of this variable's purpose */
+	int			flags;			/* flag bits, see below */
+	/* variable fields, initialized at runtime: */
+	enum config_type vartype;	/* type of variable (set only at startup) */
+	int			status;			/* status bits, see below */
+	GucSource	reset_source;	/* source of the reset_value */
+	GucSource	session_source; /* source of the session_value */
+	GucSource	tentative_source;		/* source of the tentative_value */
+	GucSource	source;			/* source of the current actual value */
+};
+
+/* bit values in flags field */
+#define GUC_LIST_INPUT			0x0001	/* input can be list format */
+#define GUC_LIST_QUOTE			0x0002	/* double-quote list elements */
+#define GUC_NO_SHOW_ALL			0x0004	/* exclude from SHOW ALL */
+#define GUC_NO_RESET_ALL		0x0008	/* exclude from RESET ALL */
+#define GUC_REPORT				0x0010	/* auto-report changes to client */
+#define GUC_NOT_IN_SAMPLE 		0x0020	/* not in postgresql.conf.sample */
+#define GUC_DISALLOW_IN_FILE	0x0040	/* can't set in postgresql.conf */ 
+
+/* bit values in status field */
+#define GUC_HAVE_TENTATIVE	0x0001		/* tentative value is defined */
+#define GUC_HAVE_LOCAL		0x0002		/* a SET LOCAL has been executed */
+
+
+/* GUC records for specific variable types */
+
+struct config_bool
+{
+	struct config_generic gen;
+	/* these fields must be set correctly in initial value: */
+	/* (all but reset_val are constants) */
+	bool	   *variable;
+	bool		reset_val;
+	bool		(*assign_hook) (bool newval, bool doit, bool interactive);
+	const char *(*show_hook) (void);
+	/* variable fields, initialized at runtime: */
+	bool		session_val;
+	bool		tentative_val;
+};
+
+struct config_int
+{
+	struct config_generic gen;
+	/* these fields must be set correctly in initial value: */
+	/* (all but reset_val are constants) */
+	int		   *variable;
+	int			reset_val;
+	int			min;
+	int			max;
+	bool		(*assign_hook) (int newval, bool doit, bool interactive);
+	const char *(*show_hook) (void);
+	/* variable fields, initialized at runtime: */
+	int			session_val;
+	int			tentative_val;
+};
+
+struct config_real
+{
+	struct config_generic gen;
+	/* these fields must be set correctly in initial value: */
+	/* (all but reset_val are constants) */
+	double	   *variable;
+	double		reset_val;
+	double		min;
+	double		max;
+	bool		(*assign_hook) (double newval, bool doit, bool interactive);
+	const char *(*show_hook) (void);
+	/* variable fields, initialized at runtime: */
+	double		session_val;
+	double		tentative_val;
+};
+
+struct config_string
+{
+	struct config_generic gen;
+	/* these fields must be set correctly in initial value: */
+	/* (all are constants) */
+	char	  **variable;
+	const char *boot_val;
+	const char *(*assign_hook) (const char *newval, bool doit, bool interactive);
+	const char *(*show_hook) (void);
+	/* variable fields, initialized at runtime: */
+	char	   *reset_val;
+	char	   *session_val;
+	char	   *tentative_val;
+};
+
+extern const char * const config_group_names[];
+extern struct config_generic **guc_variables;
+extern int	num_guc_variables;
+
+extern void build_guc_variables(void);
+
+#endif

src/include/utils/help_config.h

@@ -0,0 +1,17 @@
+/*-------------------------------------------------------------------------
+ *
+ * help_config.h
+ *		Interface to the --help-config option of main.c 
+ * 
+ * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ *
+ *	  $Id: help_config.h,v 1.1 2003/07/04 16:41:22 tgl Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef HELP_CONFIG_H
+#define HELP_CONFIG_H 1
+
+extern int	GucInfoMain(int argc, char *argv[]);
+
+#endif