ECPG support for string pseudo-type

Hi,

in a continued effort for better Informix ESQL/C compatibility,
we added the "string" pseudo-type handling to ECPG.
This type in ESQL/C is documented as:

--------------------------------------------------
The string Data Type

The string data type is an ESQL/C data type that holds character data
that is
null terminated and does not contain trailing blanks. When an application
reads a value from a CHAR column into a host variable of data type
string, it
strips the value of any trailing blanks and appends a null terminator. The
behavior is the same if an application reads a value from a VARCHAR column
into a host variable of data type string.
Declare the string data type with a length of [n+1] (where n is the size
of the
column with values that you want read) to allow for the null terminator. Use
the following syntax to declare a host variable of the string data type:
EXEC SQL BEGIN DECLARE SECTION;
string str_name[n + 1];
EXEC SQL END DECLARE SECTION;
--------------------------------------------------

So, we added it accordingly. This means the following:
- "string" has become a type name, reserved word in ECPG.
- When ECPG encounters "string", it will be transparently replaced by
"char" in the generated C source, but ECPGt_string will be passed
to ECPGdo()
- ecpg_get_data() right-trims the string value if ECPGt_string was passed.

Two regression tests had to be modified because "string" is now
a type name: preproc/define.pgc and preproc/type.pgc.

The attached patch is built upon our previous patch supporting
dynamic cursor and SQLDA.

Best regards,
Zoltán Böszörményi

--
Bible has answers for everything. Proof:
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than these cometh of evil." (Matthew 5:37) - basics of digital technology.
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----------------------------------
Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
http://www.postgresql.at/