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# strchr() Author: Kees J. Bot 1 Jan 1994
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/*	strchr()					Author: Kees J. Bot */
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/*								1 Jan 1994 */
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# char *strchr(const char *s, int c)
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/* char *strchr(const char *s, int c) */
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# Look for a character in a string.
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/*	Look for a character in a string. */
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.intel_syntax
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/* */
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.globl _strchr
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#include "asm.h"
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.text
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           .align  16
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_strchr:
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ENTRY(strchr)
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           push    ebp
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	push	%ebp
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           mov     ebp, esp
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	movl	%esp, %ebp
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           push    edi
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	push	%edi
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           cld
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	cld
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           mov     edi, [ebp+8]    # edi = string
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	movl	8(%ebp), %edi	/* edi = string */
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           mov     edx, 16         # Look at small chunks of the string
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	movl	$16, %edx	/* Look at small chunks of the string */
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next:
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next:
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           shl     edx, 1          # Chunks become bigger each time
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	shll	$1, %edx	/* Chunks become bigger each time */
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           mov     ecx, edx
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	movl	%edx, %ecx
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	xorb	%al, %al	/* Look for the zero at the end */
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           xorb    al, al          # Look for the zero at the end
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	repne scasb
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	pushf	/* Remember the flags */
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	subl	%edx, %ecx
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	negl	%ecx	/* Some or all of the chunk */
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	subl	%ecx, %edi	/* Step back */
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           repne scasb
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           pushf                   # Remember the flags
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           sub     ecx, edx
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           neg     ecx             # Some or all of the chunk
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           sub     edi, ecx        # Step back
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	movb	12(%ebp), %al	/* The character to look for */
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           movb    al, [ebp+12]    # The character to look for
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           repne scasb
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           je      found
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	repne scasb
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           popf                    # Did we find the end of string earlier?
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	je	found
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           jne     next            # No, try again
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	popf	/* Did we find the end of string earlier? */
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	jne	next	/* No, try again */
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           xor     eax, eax        # Return NULL
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	xorl	%eax, %eax	/* Return NULL */
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           pop     edi
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	pop	%edi
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           pop     ebp
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	pop	%ebp
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           ret
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	ret
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found:
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found:
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           pop     eax             # Get rid of those flags
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	pop	%eax	/* Get rid of those flags */
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           lea     eax, [edi-1]    # Address of byte found
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	leal	-1(%edi), %eax	/* Address of byte found */
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           pop     edi
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	pop	%edi