granicus.if.org Git - postgresql/blob - src/backend/commands/proclang.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * proclang.c
   4  *        PostgreSQL PROCEDURAL LANGUAGE support code.
   5  *
   6  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * IDENTIFICATION
  10  *        $Header: /cvsroot/pgsql/src/backend/commands/proclang.c,v 1.29 2002/02/18 23:11:11 petere Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #include "postgres.h"
  15
  16 #include <ctype.h>
  17
  18 #include "access/heapam.h"
  19 #include "catalog/catname.h"
  20 #include "catalog/indexing.h"
  21 #include "catalog/pg_language.h"
  22 #include "catalog/pg_proc.h"
  23 #include "commands/proclang.h"
  24 #include "fmgr.h"
  25 #include "miscadmin.h"
  26 #include "utils/builtins.h"
  27 #include "utils/syscache.h"
  28
  29
  30 /*
  31  * Translate the input language name to lower case.
  32  */
  33 static void
  34 case_translate_language_name(const char *input, char *output)
  35 {
  36         int                     i;
  37
  38         for (i = 0; i < NAMEDATALEN && input[i]; ++i)
  39                 output[i] = tolower((unsigned char) input[i]);
  40
  41         output[i] = '\0';
  42 }
  43
  44
  45 /* ---------------------------------------------------------------------
  46  * CREATE PROCEDURAL LANGUAGE
  47  * ---------------------------------------------------------------------
  48  */
  49 void
  50 CreateProceduralLanguage(CreatePLangStmt *stmt)
  51 {
  52         char            languageName[NAMEDATALEN];
  53         HeapTuple       procTup;
  54
  55         Oid                     typev[FUNC_MAX_ARGS];
  56         char            nulls[Natts_pg_language];
  57         Datum           values[Natts_pg_language];
  58         Relation        rel;
  59         HeapTuple       tup;
  60         TupleDesc       tupDesc;
  61
  62         int                     i;
  63
  64         /*
  65          * Check permission
  66          */
  67         if (!superuser())
  68                 elog(ERROR, "Only users with Postgres superuser privilege are "
  69                          "permitted to create procedural languages");
  70
  71         /*
  72          * Translate the language name and check that this language doesn't
  73          * already exist
  74          */
  75         case_translate_language_name(stmt->plname, languageName);
  76
  77         if (SearchSysCacheExists(LANGNAME,
  78                                                          PointerGetDatum(languageName),
  79                                                          0, 0, 0))
  80                 elog(ERROR, "Language %s already exists", languageName);
  81
  82         /*
  83          * Lookup the PL handler function and check that it is of return type
  84          * Opaque
  85          */
  86         memset(typev, 0, sizeof(typev));
  87         procTup = SearchSysCache(PROCNAME,
  88                                                          PointerGetDatum(stmt->plhandler),
  89                                                          Int32GetDatum(0),
  90                                                          PointerGetDatum(typev),
  91                                                          0);
  92         if (!HeapTupleIsValid(procTup))
  93                 elog(ERROR, "PL handler function %s() doesn't exist",
  94                          stmt->plhandler);
  95         if (((Form_pg_proc) GETSTRUCT(procTup))->prorettype != InvalidOid)
  96                 elog(ERROR, "PL handler function %s() isn't of return type Opaque",
  97                          stmt->plhandler);
  98
  99         /*
 100          * Insert the new language into pg_language
 101          */
 102         for (i = 0; i < Natts_pg_language; i++)
 103         {
 104                 nulls[i] = ' ';
 105                 values[i] = (Datum) NULL;
 106         }
 107
 108         i = 0;
 109         values[i++] = PointerGetDatum(languageName);
 110         values[i++] = BoolGetDatum(true);       /* lanispl */
 111         values[i++] = BoolGetDatum(stmt->pltrusted);
 112         values[i++] = ObjectIdGetDatum(procTup->t_data->t_oid);
 113         values[i++] = DirectFunctionCall1(textin,
 114                                                                           CStringGetDatum(stmt->plcompiler));
 115         nulls[i] = 'n';                         /* lanacl */
 116
 117         ReleaseSysCache(procTup);
 118
 119         rel = heap_openr(LanguageRelationName, RowExclusiveLock);
 120
 121         tupDesc = rel->rd_att;
 122         tup = heap_formtuple(tupDesc, values, nulls);
 123
 124         heap_insert(rel, tup);
 125
 126         if (RelationGetForm(rel)->relhasindex)
 127         {
 128                 Relation        idescs[Num_pg_language_indices];
 129
 130                 CatalogOpenIndices(Num_pg_language_indices, Name_pg_language_indices, idescs);
 131                 CatalogIndexInsert(idescs, Num_pg_language_indices, rel, tup);
 132                 CatalogCloseIndices(Num_pg_language_indices, idescs);
 133         }
 134
 135         heap_close(rel, RowExclusiveLock);
 136 }
 137
 138
 139 /* ---------------------------------------------------------------------
 140  * DROP PROCEDURAL LANGUAGE
 141  * ---------------------------------------------------------------------
 142  */
 143 void
 144 DropProceduralLanguage(DropPLangStmt *stmt)
 145 {
 146         char            languageName[NAMEDATALEN];
 147         HeapTuple       langTup;
 148         Relation        rel;
 149
 150         /*
 151          * Check permission
 152          */
 153         if (!superuser())
 154                 elog(ERROR, "Only users with Postgres superuser privilege are "
 155                          "permitted to drop procedural languages");
 156
 157         /*
 158          * Translate the language name, check that this language exist and is
 159          * a PL
 160          */
 161         case_translate_language_name(stmt->plname, languageName);
 162
 163         rel = heap_openr(LanguageRelationName, RowExclusiveLock);
 164
 165         langTup = SearchSysCacheCopy(LANGNAME,
 166                                                                  PointerGetDatum(languageName),
 167                                                                  0, 0, 0);
 168         if (!HeapTupleIsValid(langTup))
 169                 elog(ERROR, "Language %s doesn't exist", languageName);
 170
 171         if (!((Form_pg_language) GETSTRUCT(langTup))->lanispl)
 172                 elog(ERROR, "Language %s isn't a created procedural language",
 173                          languageName);
 174
 175         simple_heap_delete(rel, &langTup->t_self);
 176
 177         heap_freetuple(langTup);
 178         heap_close(rel, RowExclusiveLock);
 179 }