Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * kwlookup.h
       4             :  *    Key word lookup for PostgreSQL
       5             :  *
       6             :  *
       7             :  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
       8             :  * Portions Copyright (c) 1994, Regents of the University of California
       9             :  *
      10             :  * src/include/common/kwlookup.h
      11             :  *
      12             :  *-------------------------------------------------------------------------
      13             :  */
      14             : #ifndef KWLOOKUP_H
      15             : #define KWLOOKUP_H
      16             : 
      17             : /* Hash function used by ScanKeywordLookup */
      18             : typedef int (*ScanKeywordHashFunc) (const void *key, size_t keylen);
      19             : 
      20             : /*
      21             :  * This struct contains the data needed by ScanKeywordLookup to perform a
      22             :  * search within a set of keywords.  The contents are typically generated by
      23             :  * src/tools/gen_keywordlist.pl from a header containing PG_KEYWORD macros.
      24             :  */
      25             : typedef struct ScanKeywordList
      26             : {
      27             :     const char *kw_string;      /* all keywords in order, separated by \0 */
      28             :     const uint16 *kw_offsets;   /* offsets to the start of each keyword */
      29             :     ScanKeywordHashFunc hash;   /* perfect hash function for keywords */
      30             :     int         num_keywords;   /* number of keywords */
      31             :     int         max_kw_len;     /* length of longest keyword */
      32             : } ScanKeywordList;
      33             : 
      34             : 
      35             : extern int  ScanKeywordLookup(const char *str, const ScanKeywordList *keywords);
      36             : 
      37             : /* Code that wants to retrieve the text of the N'th keyword should use this. */
      38             : static inline const char *
      39    12092478 : GetScanKeyword(int n, const ScanKeywordList *keywords)
      40             : {
      41    12092478 :     return keywords->kw_string + keywords->kw_offsets[n];
      42             : }
      43             : 
      44             : #endif                          /* KWLOOKUP_H */