[src/trunk]: src/common/lib/libc/arch/arm/string Thumb versions of strcpy/str...

[matt <matt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5d1dbcbab937
branches:  trunk
changeset: 789500:5d1dbcbab937
user:      matt <matt%NetBSD.org@localhost>
date:      Tue Aug 20 21:32:50 2013 +0000

description:
Thumb versions of strcpy/strlcpy/strncpy

diffstat:

 common/lib/libc/arch/arm/string/strcpy_thumb.S |  102 +++++++++++++++++++++++++
 1 files changed, 102 insertions(+), 0 deletions(-)

diffs (106 lines):

diff -r cda43376173a -r 5d1dbcbab937 common/lib/libc/arch/arm/string/strcpy_thumb.S
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/common/lib/libc/arch/arm/string/strcpy_thumb.S    Tue Aug 20 21:32:50 2013 +0000
@@ -0,0 +1,102 @@
+/*-
+ * Copyright (c) 2013 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Matt Thomas of 3am Software Foundry.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <machine/asm.h>
+
+RCSID("$NetBSD: strcpy_thumb.S,v 1.1 2013/08/20 21:32:50 matt Exp $")
+
+#ifdef _LIBC
+#ifdef STRLCPY
+WEAK_ALIAS(strlcpy, _strlcpy)           
+#endif
+#include "namespace.h"
+#endif
+
+/*
+ * These are "naive" versions of the str*cpy routines designed to be simple
+ * and small.
+ */
+
+#if defined(STRLCPY)
+/* LINTSTUB: size_t strlcpy(char *, const char *, size_t) */
+ENTRY(strlcpy)
+       adds    r3, r1, #1              /* save src pointer (+ NUL) */
+       subs    r2, r2, #1              /* make sure there's room for a NUL */
+       blt     3f                      /*   no room, do the strlen */
+       adds    r2, r2, r0              /* get end of dst */
+       subs    r0, r0, r1              /* bias against r1 so one incr */
+1:     cmp     r0, r2                  /* room for another char? */
+       beq     2f                      /*   no, write NUL and do the strlen */
+       ldrb    r3, [r1]                /* read a byte */
+       strb    r3, [r0, r1]            /* write a byte */
+       adds    r1, r1, #1              /* advance to next byte */
+       cmp     r3, #0                  /* was it a NUL? */
+       bne     1b                      /*   no, do next byte */
+       b       4f                      /*   yes, end of string, so return */
+2:     movs    r3, #0                  /* NUL */
+       strb    r3, [r0]                /* write to end of string */
+3:     ldrb    r3, [r1]                /* read a byte */
+       adds    r1, r1, #1              /* advance to next byte */
+       cmp     r3, #0                  /* was it a NUL? */
+       bne     3b                      /*   no, get next byte */
+4:     subs    r0, r1, r3              /* return length of src string */
+       RET
+END(strlcpy)
+#elif defined(STRNCPY)
+/* LINTSTUB: char * strncpy(char *, const char *, size_t) */
+ENTRY(strncpy)
+       mov     ip, r0                  /* we want to preserve r0 */
+       adds    r2, r2, r0              /* get end of dst buffer */
+       subs    r1, r1, r0              /* allows to only increment once */
+1:     cmp     r0, r2                  /* are at the end of dst already? */
+       beq     3f                      /*   yes, just return. */
+       ldrb    r3, [r1, r0]            /* read a byte */
+       strb    r3, [r0]                /* write a byte */
+       adds    r0, r0, #1              /* advance a byte */
+       cmp     r3, #0                  /* was it a NUL? */
+       bne     1b                      /*   no, try next byte */
+2:     cmp     r0, r2                  /* are at the end of dst already? */
+       beq     3f                      /*   yes, exit loop
+       strb    r3, [r0]                /* write a NUL */
+       adds    r0, r0, #1              /* advance a bytes */
+       b       2b                      /* until dst is filled */
+3:     mov     r0, ip                  /* return dst pointer */
+       RET
+END(strncpy)
+#else
+/* LINTSTUB: char * strcpy(char *, const char *) */
+ENTRY(strcpy)
+       subs    r2, r0, r1              /* we want to preserve r0 */
+1:     ldrb    r3, [r1]                /* read a byte */
+       strb    r3, [r2, r1]            /* write a byte */
+       adds    r1, r1, #1              /* advance to next byte */
+       cmp     r3, #0                  /* was it a NUL? */
+       bne     1b                      /*   no, try next byte */
+       RET                             /* return dst pointer */
+END(strcpy)
+#endif