Fix a couple of issues in recent patch to print updates to postgresql.conf

settings: avoid calling superuser() in contexts where it's not defined,
don't leak the transient copies of GetConfigOption output, and avoid the
whole exercise in postmaster child processes.

I found that actually no current caller of GetConfigOption has any use for
its internal check of GUC_SUPERUSER_ONLY.  But rather than just remove
that entirely, it seemed better to add a parameter indicating whether to
enforce the check.

Per report from Simon and subsequent testing.

diff --git a/src/backend/utils/misc/guc-file.l b/src/backend/utils/misc/guc-file.l
index a425cd48ac0f490c1e2221e5f79382717f6a7d06..424caea13f5858d06a6249c5f9a6ee320fd106b7 100644 (file)
--- a/src/backend/utils/misc/guc-file.l
+++ b/src/backend/utils/misc/guc-file.l
@@ -4,7 +4,7 @@
  *
  * Copyright (c) 2000-2009, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/backend/utils/misc/guc-file.l,v 1.61 2009/09/17 21:15:18 petere Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/misc/guc-file.l,v 1.62 2009/10/03 18:04:57 tgl Exp $
  */
 
 %{
@@ -312,21 +312,26 @@ ProcessConfigFile(GucContext context)
    /* If we got here all the options checked out okay, so apply them. */
    for (item = head; item; item = item->next)
    {
-       char *pre_value = NULL;
+       char   *pre_value = NULL;
 
-       if (context == PGC_SIGHUP)
-           pre_value = pstrdup(GetConfigOption(item->name));
+       /* In SIGHUP cases in the postmaster, report changes */
+       if (context == PGC_SIGHUP && !IsUnderPostmaster)
+           pre_value = pstrdup(GetConfigOption(item->name, false));
 
        if (set_config_option(item->name, item->value, context,
                                 PGC_S_FILE, GUC_ACTION_SET, true))
        {
-           if (pre_value && strcmp(pre_value, GetConfigOption(item->name)) != 0)
+           set_config_sourcefile(item->name, item->filename,
+                                 item->sourceline);
+           if (pre_value &&
+               strcmp(pre_value, GetConfigOption(item->name, false)) != 0)
                ereport(elevel,
                        (errmsg("parameter \"%s\" changed to \"%s\"",
                                item->name, item->value)));
-           set_config_sourcefile(item->name, item->filename,
-                                 item->sourceline);
        }
+
+       if (pre_value)
+           pfree(pre_value);
    }
 
    /* Remember when we last successfully loaded the config file. */

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index cb743bb55ef4219dc311cf967aeb4aade81bd629..4d5aeee85ce023a128643691b0d72e844956c345 100644 (file)
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.519 2009/09/22 23:43:38 tgl Exp $
+ *   $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.520 2009/10/03 18:04:57 tgl Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -5197,11 +5197,15 @@ SetConfigOption(const char *name, const char *value,
  * Fetch the current value of the option `name'. If the option doesn't exist,
  * throw an ereport and don't return.
  *
+ * If restrict_superuser is true, we also enforce that only superusers can
+ * see GUC_SUPERUSER_ONLY variables.  This should only be passed as true
+ * in user-driven calls.
+ *
  * The string is *not* allocated for modification and is really only
  * valid until the next call to configuration related functions.
  */
 const char *
-GetConfigOption(const char *name)
+GetConfigOption(const char *name, bool restrict_superuser)
 {
    struct config_generic *record;
    static char buffer[256];
@@ -5211,7 +5215,9 @@ GetConfigOption(const char *name)
        ereport(ERROR,
                (errcode(ERRCODE_UNDEFINED_OBJECT),
               errmsg("unrecognized configuration parameter \"%s\"", name)));
-   if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
+   if (restrict_superuser &&
+       (record->flags & GUC_SUPERUSER_ONLY) &&
+       !superuser())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("must be superuser to examine \"%s\"", name)));

diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 435a722aa0b6b7f93657e5eade41a9ba1a35f00a..ef93d0f27cd1128fc62c0683555abf93aae852b4 100644 (file)
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -7,7 +7,7 @@
  * Copyright (c) 2000-2009, PostgreSQL Global Development Group
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
- * $PostgreSQL: pgsql/src/include/utils/guc.h,v 1.105 2009/09/22 23:43:41 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/guc.h,v 1.106 2009/10/03 18:04:57 tgl Exp $
  *--------------------------------------------------------------------
  */
 #ifndef GUC_H
@@ -249,7 +249,7 @@ extern void DefineCustomEnumVariable(
 
 extern void EmitWarningsOnPlaceholders(const char *className);
 
-extern const char *GetConfigOption(const char *name);
+extern const char *GetConfigOption(const char *name, bool restrict_superuser);
 extern const char *GetConfigOptionResetString(const char *name);
 extern void ProcessConfigFile(GucContext context);
 extern void InitializeGUCOptions(void);

diff --git a/src/timezone/pgtz.c b/src/timezone/pgtz.c
index 82a02438780d39a72e78a532d15c3b81b566b6cf..ea26bbd3d3984f56e3f16da5beaf6e1eb01750f0 100644 (file)
--- a/src/timezone/pgtz.c
+++ b/src/timezone/pgtz.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/timezone/pgtz.c,v 1.63 2009/06/11 14:49:15 momjian Exp $
+ *   $PostgreSQL: pgsql/src/timezone/pgtz.c,v 1.64 2009/10/03 18:04:57 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1366,7 +1366,7 @@ pg_timezone_initialize(void)
    pg_tz      *def_tz = NULL;
 
    /* Do we need to try to figure the session timezone? */
-   if (pg_strcasecmp(GetConfigOption("timezone"), "UNKNOWN") == 0)
+   if (pg_strcasecmp(GetConfigOption("timezone", false), "UNKNOWN") == 0)
    {
        /* Select setting */
        def_tz = select_default_timezone();
@@ -1377,7 +1377,7 @@ pg_timezone_initialize(void)
    }
 
    /* What about the log timezone? */
-   if (pg_strcasecmp(GetConfigOption("log_timezone"), "UNKNOWN") == 0)
+   if (pg_strcasecmp(GetConfigOption("log_timezone", false), "UNKNOWN") == 0)
    {
        /* Select setting, but don't duplicate work */
        if (!def_tz)