Repair core dump when trying to delete an entry from an already-NULL

datconfig or useconfig field.  Per report from Dustin Sallings.

diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 291770f98cc1c30a1af0597c16e840b65e290ab5..f2973d6b16551fae1583494476c95428c970a113 100644 (file)
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/commands/dbcommands.c,v 1.107 2002/11/02 18:41:21 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/commands/dbcommands.c,v 1.108 2002/12/02 05:20:47 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -561,7 +561,10 @@ AlterDatabaseSet(AlterDatabaseSetStmt *stmt)
        else
            a = GUCArrayDelete(a, stmt->variable);
 
-       repl_val[Anum_pg_database_datconfig - 1] = PointerGetDatum(a);
+       if (a)
+           repl_val[Anum_pg_database_datconfig - 1] = PointerGetDatum(a);
+       else
+           repl_null[Anum_pg_database_datconfig - 1] = 'n';
    }
 
    newtuple = heap_modifytuple(tuple, rel, repl_val, repl_null, repl_repl);

diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index a9b1e5d05f25dcf652afa80ec9e2b3508531f5e6..3bba3f6188727acfc64165f26c226d4f2ef67831 100644 (file)
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Header: /cvsroot/pgsql/src/backend/commands/user.c,v 1.113 2002/10/21 19:46:45 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/user.c,v 1.114 2002/12/02 05:20:47 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -915,8 +915,10 @@ AlterUserSet(AlterUserSetStmt *stmt)
 
    repl_repl[Anum_pg_shadow_useconfig - 1] = 'r';
    if (strcmp(stmt->variable, "all") == 0 && valuestr == NULL)
+   {
        /* RESET ALL */
        repl_null[Anum_pg_shadow_useconfig - 1] = 'n';
+   }
    else
    {
        Datum       datum;
@@ -935,7 +937,10 @@ AlterUserSet(AlterUserSetStmt *stmt)
        else
            array = GUCArrayDelete(array, stmt->variable);
 
-       repl_val[Anum_pg_shadow_useconfig - 1] = PointerGetDatum(array);
+       if (array)
+           repl_val[Anum_pg_shadow_useconfig - 1] = PointerGetDatum(array);
+       else
+           repl_null[Anum_pg_shadow_useconfig - 1] = 'n';
    }
 
    newtuple = heap_modifytuple(oldtuple, rel, repl_val, repl_null, repl_repl);

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index c26c4c740765309bcf78738955d331f48a6a16d2..02c78e0de016545a6a70252688eb681e99993712 100644 (file)
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -5,7 +5,7 @@
  * command, configuration file, and command line options.
  * See src/backend/utils/misc/README for more information.
  *
- * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.107 2002/11/21 00:42:19 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.108 2002/12/02 05:20:47 tgl Exp $
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  * Written by Peter Eisentraut .
@@ -2754,7 +2754,7 @@ assign_defaultxactisolevel(const char *newval, bool doit, bool interactive)
 
 /*
  * Handle options fetched from pg_database.datconfig or pg_shadow.useconfig.
- * The array parameter must be an array of TEXT.
+ * The array parameter must be an array of TEXT (it must not be NULL).
  */
 void
 ProcessGUCArray(ArrayType *array, GucSource source)
@@ -2809,7 +2809,10 @@ ProcessGUCArray(ArrayType *array, GucSource source)
 }
 
 
-
+/*
+ * Add an entry to an option array.  The array parameter may be NULL
+ * to indicate the current table entry is NULL.
+ */
 ArrayType *
 GUCArrayAdd(ArrayType *array, const char *name, const char *value)
 {
@@ -2880,7 +2883,11 @@ GUCArrayAdd(ArrayType *array, const char *name, const char *value)
 }
 
 
-
+/*
+ * Delete an entry from an option array.  The array parameter may be NULL
+ * to indicate the current table entry is NULL.  Also, if the return value
+ * is NULL then a null should be stored.
+ */
 ArrayType *
 GUCArrayDelete(ArrayType *array, const char *name)
 {
@@ -2889,16 +2896,17 @@ GUCArrayDelete(ArrayType *array, const char *name)
    int         index;
 
    Assert(name);
-   Assert(array);
 
    /* test if the option is valid */
    set_config_option(name, NULL,
                      superuser() ? PGC_SUSET : PGC_USERSET,
                      PGC_S_SESSION, false, false);
 
-   newarray = construct_array(NULL, 0,
-                              TEXTOID,
-                              -1, false, 'i');
+   /* if array is currently null, then surely nothing to delete */
+   if (!array)
+       return NULL;
+
+   newarray = NULL;
    index = 1;
 
    for (i = 1; i <= ARR_DIMS(array)[0]; i++)
@@ -2917,18 +2925,28 @@ GUCArrayDelete(ArrayType *array, const char *name)
            continue;
        val = DatumGetCString(DirectFunctionCall1(textout, d));
 
+       /* ignore entry if it's what we want to delete */
        if (strncmp(val, name, strlen(name)) == 0
            && val[strlen(name)] == '=')
            continue;
 
-       isnull = false;
-       newarray = array_set(newarray, 1, &index,
-                            d,
-                            -1 /* varlenarray */ ,
-                            -1 /* TEXT's typlen */ ,
-                            false /* TEXT's typbyval */ ,
-                            'i' /* TEXT's typalign */ ,
-                            &isnull);
+       /* else add it to the output array */
+       if (newarray)
+       {
+           isnull = false;
+           newarray = array_set(newarray, 1, &index,
+                                d,
+                                -1 /* varlenarray */ ,
+                                -1 /* TEXT's typlen */ ,
+                                false /* TEXT's typbyval */ ,
+                                'i' /* TEXT's typalign */ ,
+                                &isnull);
+       }
+       else
+           newarray = construct_array(&d, 1,
+                                      TEXTOID,
+                                      -1, false, 'i');
+
        index++;
    }