Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * c_keywords.c
       4             :  *    lexical token lookup for reserved words in postgres embedded SQL
       5             :  *
       6             :  * src/interfaces/ecpg/preproc/c_keywords.c
       7             :  *
       8             :  *-------------------------------------------------------------------------
       9             :  */
      10             : #include "postgres_fe.h"
      11             : 
      12             : /* ScanKeywordList lookup data for C keywords */
      13             : #include "c_kwlist_d.h"
      14             : #include "preproc_extern.h"
      15             : #include "preproc.h"
      16             : 
      17             : /* Token codes for C keywords */
      18             : #define PG_KEYWORD(kwname, value) value,
      19             : 
      20             : static const uint16 ScanCKeywordTokens[] = {
      21             : #include "c_kwlist.h"
      22             : };
      23             : 
      24             : #undef PG_KEYWORD
      25             : 
      26             : 
      27             : /*
      28             :  * ScanCKeywordLookup - see if a given word is a keyword
      29             :  *
      30             :  * Returns the token value of the keyword, or -1 if no match.
      31             :  *
      32             :  * Do a hash search using plain strcmp() comparison.  This is much like
      33             :  * ScanKeywordLookup(), except we want case-sensitive matching.
      34             :  */
      35             : int
      36       20110 : ScanCKeywordLookup(const char *text)
      37             : {
      38             :     size_t      len;
      39             :     int         h;
      40             :     const char *kw;
      41             : 
      42             :     /*
      43             :      * Reject immediately if too long to be any keyword.  This saves useless
      44             :      * hashing work on long strings.
      45             :      */
      46       20110 :     len = strlen(text);
      47       20110 :     if (len > ScanCKeywords.max_kw_len)
      48        2754 :         return -1;
      49             : 
      50             :     /*
      51             :      * Compute the hash function.  Since it's a perfect hash, we need only
      52             :      * match to the specific keyword it identifies.
      53             :      */
      54       17356 :     h = ScanCKeywords_hash_func(text, len);
      55             : 
      56             :     /* An out-of-range result implies no match */
      57       17356 :     if (h < 0 || h >= ScanCKeywords.num_keywords)
      58        9808 :         return -1;
      59             : 
      60        7548 :     kw = GetScanKeyword(h, &ScanCKeywords);
      61             : 
      62        7548 :     if (strcmp(kw, text) == 0)
      63        1868 :         return ScanCKeywordTokens[h];
      64             : 
      65        5680 :     return -1;
      66             : }