# strchrnul_P.S

/* Copyright (c) 2007  Dmitry Xmelkov

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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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/* $Id$ */

/** \file */
/** \ingroup avr_pgmspace
\fn PGM_P strchrnul_P(PGM_P s, int c)

The strchrnul_P() function is like strchr_P() except that if \p c is
not found in \p s, then it returns a pointer to the null byte at the
end of \p s, rather than \c NULL. (Glibc, GNU extension.)

\return The strchrnul_P() function returns a pointer to the matched
character, or a pointer to the null byte at the end of \p s (i.e.,

#if !defined(__AVR_TINY__)

#if !defined(__DOXYGEN__)

#include "asmdef.h"

#define src_lo  r24
#define val     r22

#define ret_lo  r24

ENTRY strchrnul_P
X_movw  ZL, src_lo

1:      X_lpm   r0, Z+
cp      r0, val
cpse    r0, __zero_reg__
brne    1b

sbiw    ZL, 1           ; undo post-increment
X_movw  ret_lo, ZL
ret
ENDFUNC

#endif /* not __DOXYGEN__ */

#endif /* !defined(__AVR_TINY__) */