.TH LIBJ2_STR_TO_J2I 3 LIBJ2
.SH NAME
libj2_str_to_j2i \- Parse ASCII-encoded double-max precision integer

.SH SYNOPSIS
.nf
#include <libj2.h>

int \fBlibj2_str_to_j2i\fP(
        const char *\fIs\fP, size_t \fIslen\fP, char **\fIend\fP,
        const char *\fIdigits1\fP, const char *\fIdigits2\fP,
        struct libj2_j2i *\fIa\fP);

int \fBlibj2_str_to_j2u\fP(
        const char *\fIs\fP, size_t \fIslen\fP, char **\fIend\fP,
        const char *\fIdigits1\fP, const char *\fIdigits2\fP,
        struct libj2_j2u *\fIa\fP)

int \fBlibj2_str_to_j2u_sign\fP(
        const char *\fIs\fP, size_t \fIslen\fP, char **\fIend\fP,
        const char *\fIdigits1\fP, const char *\fIdigits2\fP,
        struct libj2_j2u *\fIa\fP, int *\fInegative\fP);
.fi
.PP
Link with
.IR -lj2 .

.SH DESCRIPTION
The
.BR libj2_str_to_j2i ()
function parses
.I s
as a signed double-max precision integer.
The result is stored in
.I a
or discarded if
.I a
is
.IR NULL .
The function will read
.I s
until it finds the end of the integer,
a null byte, or has read
.I slen
bytes; whichever comes first.
Unless
.I end
is
.IR NULL ,
.I *end
will be set to
.I s
offset by the number of read bytes that
was part of the integer or leading
characters.
.PP
Any leading ASCII whitespace, as well
as any leading ASCII plus sign
.RB ( + ),
will be ignored, the all digits will be
parsed until any other character is
encountered; additionally, the if the parity
of the number of ASCII minus signs
.RB ( - )
intermixed with the leading characters is
odd, the result will be negative.
.PP
The
.BR libj2_str_to_j2u ()
function is like the
.BR libj2_str_to_j2i ()
function, except the parsed integer is
unsigned, and any ASCII minus sign
.RB ( - )
will terminate parsing.
.PP
The
.BR libj2_str_to_j2u_sign ()
function behaves like the
.BR libj2_str_to_j2u ()
function if
.I negative
is
.IR NULL ,
and like the
.BR libj2_str_to_j2i ()
function otherwise, except the
.I a
is unsigned, and
.I *negative
is set to 1 if the integer had an odd
number of ASCII minus signs
.RB ( - )
and 0 otherwise.
.PP
.I digits1
shall either be
.I NULL
(equivalent to
.BR \(dq0123456789\(dq )
for the decimal system, or the digits to use
in order of value (zero first). The radix
will be the length of
.IR digits1 ,
which must be atleast 2. Any listed digit
will be removed from the list of ignored
leading characters (including the minus sign).
The list may not contain any duplicates.
.PP
.I digits2
can be either
.IR NULL ,
for unused, or
another set of digits similar to
.IR digits1 :
symbols that will be recognised as
synonyms for the symbols at the same
position in
.IR digits1 .
.I digits2
may contain symbols found in
.IR digits1 ,
but only at the same positions.
.I digits2
must also be the same length as
.IR digits1 .
.IR digits2 's
intended purpose is to allow case-insensitivity,
for example, for hexadecimal
.I digits1
can be set to
.B \(dq0123456789abcdef\(dq
and
.I digits2
set to
.B \(dq0123456789ABCDEF\(dq .
.PP
.I digits2
must be
.I NULL
if
.I digits1
is
.IR NULL .

.SH RETURN VALUE
The
.BR libj2_str_to_j2i (),
.BR libj2_str_to_j2u (),
and
.BR libj2_str_to_j2u_sign ()
functions return 0 on success on an
error code,
.I without
setting
.IR errno ,
on failure.

.SH ERRORS
The
.BR libj2_str_to_j2i (),
.BR libj2_str_to_j2u (),
and
.BR libj2_str_to_j2u_sign ()
functions will fail if:
.TP
.B EINVAL
.I digits1
or
.IR digits2 ,
or the combination of the two,
is misconfigured.
.TP
.B EINVAL
No digit was encountered.
.IR a ,
unless
.IR NULL ,
will be set to the value zero.
.TP
.B ERANGE
The value is too large to be represented.
.IR a ,
unless
.IR NULL ,
will be set to the maximum value if the
value is positive, or minimum value if the
value is negative. (The value cannot be
for the
.BR libj2_str_to_j2u ()
function or the
.BR libj2_str_to_j2u_sign ()
function if
.I negative
is
.IR NULL .)

.SH HISTORY
The
.BR libj2_str_to_j2i (),
.BR libj2_str_to_j2u (),
and
.BR libj2_str_to_j2u_sign ()
functions were added in version 1.1 of
.BR libj2 .

.SH SEE ALSO
.BR libj2 (7),
.BR libj2_j2i_to_str (3),
.BR libj2_ju_to_j2i (3)