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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/lib/strncpy_from_user.S
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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diff --git a/arch/arm/lib/strncpy_from_user.S b/arch/arm/lib/strncpy_from_user.S
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+/*
+ * linux/arch/arm/lib/strncpy_from_user.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+
+ .text
+ .align 5
+
+/*
+ * Copy a string from user space to kernel space.
+ * r0 = dst, r1 = src, r2 = byte length
+ * returns the number of characters copied (strlen of copied string),
+ * -EFAULT on exception, or "len" if we fill the whole buffer
+ */
+ENTRY(__arch_strncpy_from_user)
+ save_lr
+ mov ip, r1
+1: subs r2, r2, #1
+USER( ldrplbt r3, [r1], #1)
+ bmi 2f
+ strb r3, [r0], #1
+ teq r3, #0
+ bne 1b
+ sub r1, r1, #1 @ take NUL character out of count
+2: sub r0, r1, ip
+ restore_pc
+
+ .section .fixup,"ax"
+ .align 0
+9001: mov r3, #0
+ strb r3, [r0, #0] @ null terminate
+ mov r0, #-EFAULT
+ restore_pc
+ .previous
+