Commit 390bc0d6 authored by unknown's avatar unknown
Browse files

Add documentation to the escape_*() functions in mysys. 


mysys/charset.c:
  Add documentation for escape functions
  Minor style cleanup
parent 86d8abdb

mysys/charset.c

+52 −16
Original line number Diff line number Diff line
@@ -561,11 +561,30 @@ CHARSET_INFO *get_charset_by_csname(const char *cs_name, 
  DBUG_RETURN(cs);

}





/*

  Escape string with backslashes (\)



  SYNOPSIS

    escape_string_for_mysql()

    charset_info        Charset of the strings

    to                  Buffer for escaped string

    to_length           Length of destination buffer, or 0

    from                The string to escape

    length              The length of the string to escape



  DESCRIPTION

    This escapes the contents of a string by adding backslashes before special

    characters, and turning others into specific escape sequences, such as

    turning newlines into \n and null bytes into \0.



  NOTE

    to keep old C API, to_length may be 0 to mean "big enough"

  RETURN

    the length of the escaped string or ~0 if it did not fit.

    To maintain compatibility with the old C API, to_length may be 0 to mean

    "big enough"



  RETURN VALUES

    ~0          The escaped string did not fit in the to buffer

    >=0         The length of the escaped string

*/

ulong escape_string_for_mysql(CHARSET_INFO *charset_info,

                              char *to, ulong to_length,
@@ -573,7 +592,7 @@ ulong escape_string_for_mysql(CHARSET_INFO *charset_info, 
{

  const char *to_start= to;

  const char *end, *to_end=to_start + (to_length ? to_length-1 : 2*length);

  my_bool overflow=0;

  my_bool overflow= FALSE;

#ifdef USE_MB

  my_bool use_mb_flag= use_mb(charset_info);

#endif
@@ -586,7 +605,7 @@ ulong escape_string_for_mysql(CHARSET_INFO *charset_info, 
    {

      if (to + tmp_length > to_end)

      {

        overflow=1;

        overflow= TRUE;

        break;

      }

      while (tmp_length--)
@@ -636,7 +655,7 @@ ulong escape_string_for_mysql(CHARSET_INFO *charset_info, 
    {

      if (to + 2 > to_end)

      {

        overflow=1;

        overflow= TRUE;

        break;

      }

      *to++= '\\';
@@ -646,7 +665,7 @@ ulong escape_string_for_mysql(CHARSET_INFO *charset_info, 
    {

      if (to + 1 > to_end)

      {

        overflow=1;

        overflow= TRUE;

        break;

      }

      *to++= *from;
@@ -658,11 +677,28 @@ ulong escape_string_for_mysql(CHARSET_INFO *charset_info, 




/*

  Escape apostrophes by doubling them up



  SYNOPSIS

    escape_quotes_for_mysql()

    charset_info        Charset of the strings

    to                  Buffer for escaped string

    to_length           Length of destination buffer, or 0

    from                The string to escape

    length              The length of the string to escape



  DESCRIPTION

    This escapes the contents of a string by doubling up any apostrophes that

    it contains. This is used when the NO_BACKSLASH_ESCAPES SQL_MODE is in

    effect on the server.



  NOTE

    to be consistent with escape_string_for_mysql(), to_length may be 0 to

    To be consistent with escape_string_for_mysql(), to_length may be 0 to

    mean "big enough"

  RETURN

    the length of the escaped string or ~0 if it did not fit.



  RETURN VALUES

    ~0          The escaped string did not fit in the to buffer

    >=0         The length of the escaped string

*/

ulong escape_quotes_for_mysql(CHARSET_INFO *charset_info,

                              char *to, ulong to_length,
@@ -670,7 +706,7 @@ ulong escape_quotes_for_mysql(CHARSET_INFO *charset_info, 
{

  const char *to_start= to;

  const char *end, *to_end=to_start + (to_length ? to_length-1 : 2*length);

  my_bool overflow=0;

  my_bool overflow= FALSE;

#ifdef USE_MB

  my_bool use_mb_flag= use_mb(charset_info);

#endif
@@ -683,7 +719,7 @@ ulong escape_quotes_for_mysql(CHARSET_INFO *charset_info, 
    {

      if (to + tmp_length > to_end)

      {

        overflow=1;

        overflow= TRUE;

        break;

      }

      while (tmp_length--)
@@ -701,7 +737,7 @@ ulong escape_quotes_for_mysql(CHARSET_INFO *charset_info, 
    {

      if (to + 2 > to_end)

      {

        overflow=1;

        overflow= TRUE;

        break;

      }

      *to++= '\'';
@@ -711,7 +747,7 @@ ulong escape_quotes_for_mysql(CHARSET_INFO *charset_info, 
    {

      if (to + 1 > to_end)

      {

        overflow=1;

        overflow= TRUE;

        break;

      }

      *to++= *from;