2000-05-28 13:40:48 +00:00
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;
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; Ullrich von Bassewitz, 31.05.1998
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;
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2017-03-05 01:09:12 +00:00
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; Note: strspn & strcspn call internally this function and rely on
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; the usage of only ptr1 here! Keep in mind when appling changes
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; and check the other implementations too!
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;
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2000-05-28 13:40:48 +00:00
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; int strlen (const char* s);
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;
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2013-05-09 11:56:54 +00:00
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.export _strlen
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.importzp ptr1
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2000-05-28 13:40:48 +00:00
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_strlen:
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2013-05-09 11:56:54 +00:00
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sta ptr1 ; Save s
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stx ptr1+1
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ldx #0 ; YX used as counter
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ldy #0
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2000-05-28 13:40:48 +00:00
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2013-05-09 11:56:54 +00:00
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L1: lda (ptr1),y
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beq L9
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iny
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bne L1
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inc ptr1+1
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inx
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bne L1
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2000-05-28 13:40:48 +00:00
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2013-05-09 11:56:54 +00:00
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L9: tya ; get low byte of counter, hi's all set
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rts
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