granicus.if.org Git - postgresql/blob - src/backend/parser/keywords.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * keywords.c
   4  *        lexical token lookup for reserved words in PostgreSQL
   5  *
   6  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.89 2001/02/21 18:53:46 tgl Exp $
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15 #include "postgres.h"
  16
  17 #include <ctype.h>
  18
  19 #include "nodes/parsenodes.h"
  20 #include "parser/keywords.h"
  21 #include "parser/parse.h"
  22
  23 /*
  24  * List of (keyword-name, keyword-token-value) pairs.
  25  *
  26  * !!WARNING!!: This list must be sorted, because binary
  27  *               search is used to locate entries.
  28  */
  29 static ScanKeyword ScanKeywords[] = {
  30         /* name, value */
  31         {"abort", ABORT_TRANS},
  32         {"absolute", ABSOLUTE},
  33         {"access", ACCESS},
  34         {"action", ACTION},
  35         {"add", ADD},
  36         {"after", AFTER},
  37         {"aggregate", AGGREGATE},
  38         {"all", ALL},
  39         {"alter", ALTER},
  40         {"analyse", ANALYSE}, /* British spelling */
  41         {"analyze", ANALYZE},
  42         {"and", AND},
  43         {"any", ANY},
  44         {"as", AS},
  45         {"asc", ASC},
  46         {"at", AT},
  47         {"backward", BACKWARD},
  48         {"before", BEFORE},
  49         {"begin", BEGIN_TRANS},
  50         {"between", BETWEEN},
  51         {"binary", BINARY},
  52         {"bit", BIT},
  53         {"both", BOTH},
  54         {"by", BY},
  55         {"cache", CACHE},
  56         {"cascade", CASCADE},
  57         {"case", CASE},
  58         {"cast", CAST},
  59         {"chain", CHAIN},
  60         {"char", CHAR},
  61         {"character", CHARACTER},
  62         {"characteristics", CHARACTERISTICS},
  63         {"check", CHECK},
  64         {"checkpoint", CHECKPOINT},
  65         {"close", CLOSE},
  66         {"cluster", CLUSTER},
  67         {"coalesce", COALESCE},
  68         {"collate", COLLATE},
  69         {"column", COLUMN},
  70         {"comment", COMMENT},
  71         {"commit", COMMIT},
  72         {"committed", COMMITTED},
  73         {"constraint", CONSTRAINT},
  74         {"constraints", CONSTRAINTS},
  75         {"copy", COPY},
  76         {"create", CREATE},
  77         {"createdb", CREATEDB},
  78         {"createuser", CREATEUSER},
  79         {"cross", CROSS},
  80         {"current_date", CURRENT_DATE},
  81         {"current_time", CURRENT_TIME},
  82         {"current_timestamp", CURRENT_TIMESTAMP},
  83         {"current_user", CURRENT_USER},
  84         {"cursor", CURSOR},
  85         {"cycle", CYCLE},
  86         {"database", DATABASE},
  87         {"day", DAY_P},
  88         {"dec", DEC},
  89         {"decimal", DECIMAL},
  90         {"declare", DECLARE},
  91         {"default", DEFAULT},
  92         {"deferrable", DEFERRABLE},
  93         {"deferred", DEFERRED},
  94         {"delete", DELETE},
  95         {"delimiters", DELIMITERS},
  96         {"desc", DESC},
  97         {"distinct", DISTINCT},
  98         {"do", DO},
  99         {"double", DOUBLE},
 100         {"drop", DROP},
 101         {"each", EACH},
 102         {"else", ELSE},
 103         {"encoding", ENCODING},
 104         {"end", END_TRANS},
 105         {"escape", ESCAPE},
 106         {"except", EXCEPT},
 107         {"exclusive", EXCLUSIVE},
 108         {"execute", EXECUTE},
 109         {"exists", EXISTS},
 110         {"explain", EXPLAIN},
 111         {"extend", EXTEND},
 112         {"extract", EXTRACT},
 113         {"false", FALSE_P},
 114         {"fetch", FETCH},
 115         {"float", FLOAT},
 116         {"for", FOR},
 117         {"force", FORCE},
 118         {"foreign", FOREIGN},
 119         {"forward", FORWARD},
 120         {"from", FROM},
 121         {"full", FULL},
 122         {"function", FUNCTION},
 123         {"global", GLOBAL},
 124         {"grant", GRANT},
 125         {"group", GROUP},
 126         {"handler", HANDLER},
 127         {"having", HAVING},
 128         {"hour", HOUR_P},
 129         {"ilike", ILIKE},
 130         {"immediate", IMMEDIATE},
 131         {"in", IN},
 132         {"increment", INCREMENT},
 133         {"index", INDEX},
 134         {"inherits", INHERITS},
 135         {"initially", INITIALLY},
 136         {"inner", INNER_P},
 137         {"inout", INOUT},
 138         {"insensitive", INSENSITIVE},
 139         {"insert", INSERT},
 140         {"instead", INSTEAD},
 141         {"intersect", INTERSECT},
 142         {"interval", INTERVAL},
 143         {"into", INTO},
 144         {"is", IS},
 145         {"isnull", ISNULL},
 146         {"isolation", ISOLATION},
 147         {"join", JOIN},
 148         {"key", KEY},
 149         {"lancompiler", LANCOMPILER},
 150         {"language", LANGUAGE},
 151         {"leading", LEADING},
 152         {"left", LEFT},
 153         {"level", LEVEL},
 154         {"like", LIKE},
 155         {"limit", LIMIT},
 156         {"listen", LISTEN},
 157         {"load", LOAD},
 158         {"local", LOCAL},
 159         {"location", LOCATION},
 160         {"lock", LOCK_P},
 161         {"match", MATCH},
 162         {"maxvalue", MAXVALUE},
 163         {"minute", MINUTE_P},
 164         {"minvalue", MINVALUE},
 165         {"mode", MODE},
 166         {"month", MONTH_P},
 167         {"move", MOVE},
 168         {"names", NAMES},
 169         {"national", NATIONAL},
 170         {"natural", NATURAL},
 171         {"nchar", NCHAR},
 172         {"new", NEW},
 173         {"next", NEXT},
 174         {"no", NO},
 175         {"nocreatedb", NOCREATEDB},
 176         {"nocreateuser", NOCREATEUSER},
 177         {"none", NONE},
 178         {"not", NOT},
 179         {"nothing", NOTHING},
 180         {"notify", NOTIFY},
 181         {"notnull", NOTNULL},
 182         {"null", NULL_P},
 183         {"nullif", NULLIF},
 184         {"numeric", NUMERIC},
 185         {"of", OF},
 186         {"off", OFF},
 187         {"offset", OFFSET},
 188         {"oids", OIDS},
 189         {"old", OLD},
 190         {"on", ON},
 191         {"only", ONLY},
 192         {"operator", OPERATOR},
 193         {"option", OPTION},
 194         {"or", OR},
 195         {"order", ORDER},
 196         {"out", OUT},
 197         {"outer", OUTER_P},
 198         {"overlaps", OVERLAPS},
 199         {"owner", OWNER},
 200         {"partial", PARTIAL},
 201         {"password", PASSWORD},
 202         {"path", PATH_P},
 203         {"pendant", PENDANT},
 204         {"position", POSITION},
 205         {"precision", PRECISION},
 206         {"primary", PRIMARY},
 207         {"prior", PRIOR},
 208         {"privileges", PRIVILEGES},
 209         {"procedural", PROCEDURAL},
 210         {"procedure", PROCEDURE},
 211         {"public", PUBLIC},
 212         {"read", READ},
 213         {"references", REFERENCES},
 214         {"reindex", REINDEX},
 215         {"relative", RELATIVE},
 216         {"rename", RENAME},
 217         {"reset", RESET},
 218         {"restrict", RESTRICT},
 219         {"returns", RETURNS},
 220         {"revoke", REVOKE},
 221         {"right", RIGHT},
 222         {"rollback", ROLLBACK},
 223         {"row", ROW},
 224         {"rule", RULE},
 225         {"schema", SCHEMA},
 226         {"scroll", SCROLL},
 227         {"second", SECOND_P},
 228         {"select", SELECT},
 229         {"sequence", SEQUENCE},
 230         {"serial", SERIAL},
 231         {"serializable", SERIALIZABLE},
 232         {"session", SESSION},
 233         {"session_user", SESSION_USER},
 234         {"set", SET},
 235         {"setof", SETOF},
 236         {"share", SHARE},
 237         {"show", SHOW},
 238         {"some", SOME},
 239         {"start", START},
 240         {"statement", STATEMENT},
 241         {"stdin", STDIN},
 242         {"stdout", STDOUT},
 243         {"substring", SUBSTRING},
 244         {"sysid", SYSID},
 245         {"table", TABLE},
 246         {"temp", TEMP},
 247         {"template", TEMPLATE},
 248         {"temporary", TEMPORARY},
 249         {"then", THEN},
 250         {"time", TIME},
 251         {"timestamp", TIMESTAMP},
 252         {"timezone_hour", TIMEZONE_HOUR},
 253         {"timezone_minute", TIMEZONE_MINUTE},
 254         {"to", TO},
 255         {"toast", TOAST},
 256         {"trailing", TRAILING},
 257         {"transaction", TRANSACTION},
 258         {"trigger", TRIGGER},
 259         {"trim", TRIM},
 260         {"true", TRUE_P},
 261         {"truncate", TRUNCATE},
 262         {"trusted", TRUSTED},
 263         {"type", TYPE_P},
 264         {"union", UNION},
 265         {"unique", UNIQUE},
 266         {"unlisten", UNLISTEN},
 267         {"until", UNTIL},
 268         {"update", UPDATE},
 269         {"user", USER},
 270         {"using", USING},
 271         {"vacuum", VACUUM},
 272         {"valid", VALID},
 273         {"values", VALUES},
 274         {"varchar", VARCHAR},
 275         {"varying", VARYING},
 276         {"verbose", VERBOSE},
 277         {"version", VERSION},
 278         {"view", VIEW},
 279         {"when", WHEN},
 280         {"where", WHERE},
 281         {"with", WITH},
 282         {"without", WITHOUT},
 283         {"work", WORK},
 284         {"year", YEAR_P},
 285         {"zone", ZONE},
 286 };
 287
 288 /*
 289  * ScanKeywordLookup - see if a given word is a keyword
 290  *
 291  * Returns a pointer to the ScanKeyword table entry, or NULL if no match.
 292  *
 293  * The match is done case-insensitively.  Note that we deliberately use a
 294  * dumbed-down case conversion that will only translate 'A'-'Z' into 'a'-'z',
 295  * even if we are in a locale where tolower() would produce more or different
 296  * translations.  This is to conform to the SQL99 spec, which says that
 297  * keywords are to be matched in this way even though non-keyword identifiers
 298  * receive a different case-normalization mapping.
 299  */
 300 ScanKeyword *
 301 ScanKeywordLookup(char *text)
 302 {
 303         int                     len,
 304                                 i;
 305         char            word[NAMEDATALEN];
 306         ScanKeyword *low;
 307         ScanKeyword *high;
 308
 309         len = strlen(text);
 310         /* We assume all keywords are shorter than NAMEDATALEN. */
 311         if (len >= NAMEDATALEN)
 312                 return NULL;
 313
 314         /*
 315          * Apply an ASCII-only downcasing.  We must not use tolower() since
 316          * it may produce the wrong translation in some locales (eg, Turkish),
 317          * and we don't trust isupper() very much either.  In an ASCII-based
 318          * encoding the tests against A and Z are sufficient, but we also check
 319          * isupper() so that we will work correctly under EBCDIC.  The actual
 320          * case conversion step should work for either ASCII or EBCDIC.
 321          */
 322         for (i = 0; i < len; i++)
 323         {
 324                 char    ch = text[i];
 325
 326                 if (ch >= 'A' && ch <= 'Z' && isupper((unsigned char) ch))
 327                         ch += 'a' - 'A';
 328                 word[i] = ch;
 329         }
 330         word[len] = '\0';
 331
 332         /*
 333          * Now do a binary search using plain strcmp() comparison.
 334          */
 335         low = &ScanKeywords[0];
 336         high = endof(ScanKeywords) - 1;
 337         while (low <= high)
 338         {
 339                 ScanKeyword *middle;
 340                 int                     difference;
 341
 342                 middle = low + (high - low) / 2;
 343                 difference = strcmp(middle->name, word);
 344                 if (difference == 0)
 345                         return middle;
 346                 else if (difference < 0)
 347                         low = middle + 1;
 348                 else
 349                         high = middle - 1;
 350         }
 351
 352         return NULL;
 353 }