TLA  Line data    Source code

       1                 : /*-------------------------------------------------------------------------
       2                 :  *
       3                 :  * stringinfo_mb.c
       4                 :  *      Multibyte encoding-aware additional StringInfo facilities
       5                 :  *
       6                 :  * This is separate from common/stringinfo.c so that frontend users
       7                 :  * of that file need not pull in unnecessary multibyte-encoding support
       8                 :  * code.
       9                 :  *
      10                 :  *
      11                 :  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
      12                 :  * Portions Copyright (c) 1994, Regents of the University of California
      13                 :  *
      14                 :  *
      15                 :  * IDENTIFICATION
      16                 :  *    src/backend/utils/mb/stringinfo_mb.c
      17                 :  *
      18                 :  *-------------------------------------------------------------------------
      19                 :  */
      20                 : #include "postgres.h"
      21                 : 
      22                 : #include "mb/stringinfo_mb.h"
      23                 : #include "mb/pg_wchar.h"
      24                 : 
      25                 : 
      26                 : /*
      27                 :  * appendStringInfoStringQuoted
      28                 :  *
      29                 :  * Append up to maxlen bytes from s to str, or the whole input string if
      30                 :  * maxlen < 0, adding single quotes around it and doubling all single quotes.
      31                 :  * Add an ellipsis if the copy is incomplete.
      32                 :  */
      33                 : void
      34 CBC        4003 : appendStringInfoStringQuoted(StringInfo str, const char *s, int maxlen)
      35                 : {
      36            4003 :     char       *copy = NULL;
      37                 :     const char *chunk_search_start,
      38                 :                *chunk_copy_start,
      39                 :                *chunk_end;
      40                 :     int         slen;
      41                 :     bool        ellipsis;
      42                 : 
      43            4003 :     Assert(str != NULL);
      44                 : 
      45            4003 :     slen = strlen(s);
      46            4003 :     if (maxlen >= 0 && maxlen < slen)
      47               6 :     {
      48               6 :         int         finallen = pg_mbcliplen(s, slen, maxlen);
      49                 : 
      50               6 :         copy = pnstrdup(s, finallen);
      51               6 :         chunk_search_start = copy;
      52               6 :         chunk_copy_start = copy;
      53                 : 
      54               6 :         ellipsis = true;
      55                 :     }
      56                 :     else
      57                 :     {
      58            3997 :         chunk_search_start = s;
      59            3997 :         chunk_copy_start = s;
      60                 : 
      61            3997 :         ellipsis = false;
      62                 :     }
      63                 : 
      64            4003 :     appendStringInfoCharMacro(str, '\'');
      65                 : 
      66            4034 :     while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
      67                 :     {
      68                 :         /* copy including the found delimiting ' */
      69              31 :         appendBinaryStringInfoNT(str,
      70                 :                                  chunk_copy_start,
      71              31 :                                  chunk_end - chunk_copy_start + 1);
      72                 : 
      73                 :         /* in order to double it, include this ' into the next chunk as well */
      74              31 :         chunk_copy_start = chunk_end;
      75              31 :         chunk_search_start = chunk_end + 1;
      76                 :     }
      77                 : 
      78                 :     /* copy the last chunk and terminate */
      79            4003 :     if (ellipsis)
      80               6 :         appendStringInfo(str, "%s...'", chunk_copy_start);
      81                 :     else
      82            3997 :         appendStringInfo(str, "%s'", chunk_copy_start);
      83                 : 
      84            4003 :     if (copy)
      85               6 :         pfree(copy);
      86            4003 : }