Tribblix: manual page: kiconvstr.9f

KICONVSTR(9F) Kernel Functions for Drivers KICONVSTR(9F)

NAME

kiconvstr - string-based code conversion function

SYNOPSIS

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/sunddi.h>

size_t kiconvstr(const char *tocode, const char *fromcode, char *inarray,
size_t *inlen, char *outarray, size_t *outlen, int flag, int *errno);

INTERFACE LEVEL

illumos DDI specific (illumos DDI).

PARAMETERS

The parameters for the kiconvstr function are as follows:

tocode
Points to a target codeset name string. Supported names
are specified at kiconv_open().

fromcode
Points to a source codeset name string. Supported names
are specified at kiconv_open().

inarray
Points to a byte array containing a sequence of character
bytes in fromcode codeset to be converted.

inlen
As an input parameter, the number of bytes to be
converted in inarray. As an output parameter, the number
of bytes in inarray still not converted after the
conversion.

outarray
Points to a byte array where converted character bytes in
tocode codeset can be saved.

outlen
As an input parameter, the number of available bytes at
outarray where converted character bytes can be saved. As
an output parameter, the number of bytes still available
at outarray after the conversion.

flag
Indicates possible conversion options constructed by a
bitwise-inclusive-OR of the following values:

KICONV_IGNORE_NULL

Normally, kiconvstr() stops the conversion if it
encounters NULL byte even if the current inlen is
pointing to a value larger than zero.

If this option is set, a NULL byte does not stop the
conversion and the conversion continues until the
number of inarray bytes pointed by inlen are all
consumed for conversion or an error happened.

KICONV_REPLACE_INVALID

Normally, kiconvstr() stops the conversion if it
encounters illegal or incomplete characters with
corresponding errno values.

If this option is set, kiconvstr() does not stop the
conversion and instead treats such characters as non-
identical conversion cases.

errno
Indicates the error when conversion is not completed or
failed. The following are possible values:

EILSEQ
The input conversion was stopped due to an
input byte that does not belong to the input
codeset.

E2BIG
The input conversion was stopped due to lack
of space in the output array.

EINVAL
The input conversion was stopped due to an
incomplete character or shift sequence at
the end of the input array.

EBADF
The requested conversion is not supported.

DESCRIPTION

The kiconvstr() function converts the sequence of characters from one
codeset, in the array specified by inarray, into a sequence of
corresponding characters in another codeset, in the array specified
by outarray. The codesets are those specified in fromcode and tocode
parameters. The inarray parameter points to a character byte array to
the first character in the input array and inlen indicates the number
of bytes to the end of the array to be converted. The outarray
parameter points to a character byte array to the first available
byte in the output array and outlen indicates the number of the
available bytes to the end of the array. Unless KICONV_IGNORE_NULL is
specified at flag, kiconvstr() function normally stops when it
encounters NULL byte from the input array regardless of the current
inlen value.

If KICONV_REPLACE_INVALID is not specified at flag and if a sequence
of input bytes does not form a valid character in the specified
codeset, conversion stops after the previous successfully converted
character. If KICONV_REPLACE_INVALID is not specified in flag and if
the input array ends with an incomplete character or shift sequence,
conversion stops after the previous successfully converted bytes. If
the output array is not large enough to hold the entire converted
input, conversion stops just prior to the input bytes that would
cause the output array to overflow. The value pointed to by inlen is
decremented to reflect the number of bytes still not converted in the
input array. The value pointed to by outlen is decremented to reflect
the number of bytes still available in the output array.

If kiconvstr() encounters a character in the input array that is
legal, but for which an identical character does not exist in the
target codeset, kiconvstr() performs an implementation-defined
conversion (that is, a non-identical conversion) on this character.

If KICONV_REPLACE_INVALID is specified in flag and if kiconvstr()
encounters illegal or incomplete characters in the input array,
instead of stopping the conversion, kiconvstr() treats such
characters as if they are non-identical characters and does non-
identical conversions on such character bytes.

RETURN VALUES

The kiconvstr() function updates the values pointed to by the inlen
and outlen parameters to reflect the extent of the conversion and
returns the number of non-identical conversions performed. If the
entire string in the input array is converted, the value pointed to
by inlen is 0. If the input conversion is stopped due to any
conditions mentioned above, the value pointed to by inlen is non-zero
and errno is set to indicate the condition. If an error occurs,
kiconvstr() returns (size_t)-1 and sets errno to indicate the error.

CONTEXT

kiconvstr() can be called from user or interrupt context.

EXAMPLES

Example 1: Performing a Code Conversion

The following example converts a NULL-terminated ISO8859-2 pathname
string to a UTF-8 string and treats illegal and incomplete characters
as non-identical conversion cases. The conversion does not stop even
if it encounters a NULL byte from the input array.

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/sunddi.h>

:

size_t ret;
char ib[MAXPATHLEN];
char ob[MAXPATHLEN];
size_t il, ol;
int err;

:

/*
* We got the pathname from somewhere.
*
* Calculate the length of input string including the terminating
* NULL byte and prepare other parameters for the conversion.
*/
(void) strlcpy(ib, pathname, MAXPATHLEN);
il = strlen(ib) + 1;
ol = MAXPATHLEN;

/*
* Do the conversion. If the ret > 0, that's the number of
* non-identical character conversions happened during the conversion.
* Regardless of whether we have conversion failure or not,
* outarray could contain some converted characters.
*/
ret = kiconvstr("UTF-8", "ISO-8859-2", ib, &il, ob, &ol,
(KICONV_IGNORE_NULL|KICONV_REPLACE_INVALID), &err);
if (ret == (size_t)-1) {
/* Code conversion not supported? */
if (err == EBADF)
return (-1);

/* Output array too small? */
if (err == E2BIG)
return (-2);

/* Unknown error which isn't possible BTW. */
return (-3);
}

ATTRIBUTES