src/port/quotes.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * quotes.c
   4  *        string quoting and escaping functions
   5  *
   6  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        src/port/quotes.c
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15
  16 #include "c.h"
  17
  18 /*
  19  * Escape (by doubling) any single quotes or backslashes in given string
  20  *
  21  * Note: this is used to process postgresql.conf entries and to quote
  22  * string literals in pg_basebackup for writing the recovery configuration.
  23  * Since postgresql.conf strings are defined to treat backslashes as escapes,
  24  * we have to double backslashes here.
  25  *
  26  * Since this function is only used for parsing or creating configuration
  27  * files, we do not care about encoding considerations.
  28  *
  29  * Returns a malloced() string that it's the responsibility of the caller
  30  * to free.
  31  */
  32 char *
  33 escape_single_quotes_ascii(const char *src)
  34 {
  35         int                     len = strlen(src),
  36                                 i,
  37                                 j;
  38         char       *result = malloc(len * 2 + 1);
  39
  40         if (!result)
  41                 return NULL;
  42
  43         for (i = 0, j = 0; i < len; i++)
  44         {
  45                 if (SQL_STR_DOUBLE(src[i], true))
  46                         result[j++] = src[i];
  47                 result[j++] = src[i];
  48         }
  49         result[j] = '\0';
  50         return result;
  51 }