Bound Input Parameter of type SQL_C_WCHAR containing surrogate pairs may be truncated [ODBC160]

Question

Bound Input Parameter of type SQL_C_WCHAR containing surrogate pairs may be truncated [ODBC160]

firebird-automations opened this issue 12 years ago · 15 comments

firebird-automations commented 12 years ago

Submitted by: Jojakim Stahl (jstahl)

Attachments:
bug-160-new.patch

Do the following (pseudo-code)

create table test (
strfield varchar(30) character set UTF8
)

SQLDriverConnect( ... CHARSET=UTF8 ...)

SQLPrepareW(hStmt, "insert into test values (?)", SQL_NTS)

SQLBindParameter(hStmt, 1, SQL_PARAM_INPUT, SQL_C_WCHAR, SQL_VARCHAR, 30, 0, str_field, sizeof(str_field), &str_field_len);

with str_field containing min 30 chars, and min. one of them beeing a surrogate pairs, means a string conating more than 30 wchar_t entities.
The string can be converted to the UTF8 field without any loss, because FB allows up to 30*4 bytes for the field. However, the driver does assume, that one wchar_t unit results in one char (covering up to 4 bytes in UTF8). The input value will be truncated to 30 wchar_t entities instead of 30 charachters.

Commits: 9fca7df d94a113

Answer 1 · 2013-02-06T16:40:05.000Z

Commented by: Jojakim Stahl (jstahl)

This patch solves the issue.
I tried to solve it with as minimal as possible code changes (at least I hope so).
The downside is one additional scan of the input string.
Otherwise I had to rework all the WcsToMbs function signatures in order to in- and output detailed string length and character count information to/from these functions.

Answer 2 · 2013-02-06T16:40:05.000Z

Modified by: Jojakim Stahl (jstahl)

Attachment: surrogate.patch [ 12285 ]

Answer 3 · 2013-02-28T19:38:07.000Z

Commented by: Jojakim Stahl (jstahl)

a second patch to apply after the first one.
tests revealed a bug in the first patch.

Answer 4 · 2013-02-28T19:38:07.000Z

Modified by: Jojakim Stahl (jstahl)

Attachment: surrogate2.patch [ 12291 ]

Answer 5 · 2014-10-31T15:46:05.000Z

Commented by: Jojakim Stahl (jstahl)

Summary patch based on current cvs-head
The patch invalidates all previously puplished patches.

Answer 6 · 2014-10-31T15:46:05.000Z

Modified by: Jojakim Stahl (jstahl)

Version: 2.0.2 [ 10465 ]

Attachment: bug-160.patch [ 12604 ]

Answer 7 · 2014-10-31T17:40:57.000Z

Commented by: Jojakim Stahl (jstahl)

Sorry, the summary patch contained changes for each line due to oel-style problem.
Please use only the "bug-160-new.patch".
The other attachments can be deleted. (I do not have permissions to do so)