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authorPeter S. Mazinger <ps.m@gmx.net>2005-11-11 22:41:52 +0000
committerPeter S. Mazinger <ps.m@gmx.net>2005-11-11 22:41:52 +0000
commit0b09d1e5ed195662e8df3246ca4cc450947cc0f8 (patch)
treef9b284000c0b9777f2681a5b15f9cac00d13b661 /libc/string/i386/strncpy.c
parent7500403c7b05536eafb0597613284416096be2a2 (diff)
Split up string.c, make internals hidden
Diffstat (limited to 'libc/string/i386/strncpy.c')
-rw-r--r--libc/string/i386/strncpy.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/libc/string/i386/strncpy.c b/libc/string/i386/strncpy.c
new file mode 100644
index 000000000..1e7257e95
--- /dev/null
+++ b/libc/string/i386/strncpy.c
@@ -0,0 +1,57 @@
+/*
+ * This string-include defines all string functions as inline
+ * functions. Use gcc. It also assumes ds=es=data space, this should be
+ * normal. Most of the string-functions are rather heavily hand-optimized,
+ * see especially strtok,strstr,str[c]spn. They should work, but are not
+ * very easy to understand. Everything is done entirely within the register
+ * set, making the functions fast and clean. String instructions have been
+ * used through-out, making for "slightly" unclear code :-)
+ *
+ * NO Copyright (C) 1991, 1992 Linus Torvalds,
+ * consider these trivial functions to be PD.
+ */
+
+/*
+ * Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/*
+ * Modified for uClibc by Erik Andersen <andersen@codepoet.org>
+ * These make no attempt to use nifty things like mmx/3dnow/etc.
+ * These are not inline, and will therefore not be as fast as
+ * modifying the headers to use inlines (and cannot therefore
+ * do tricky things when dealing with const memory). But they
+ * should (I hope!) be faster than their generic equivalents....
+ *
+ * More importantly, these should provide a good example for
+ * others to follow when adding arch specific optimizations.
+ * -Erik
+ */
+
+#define _GNU_SOURCE
+#include <string.h>
+
+char attribute_hidden *__strncpy(char * dest, const char * src, size_t count)
+{
+ int d0, d1, d2, d3;
+ __asm__ __volatile__(
+ "incl %2\n"
+ "1:\n"
+ "decl %2\n"
+ "jz 2f\n"
+ "lodsb\n\t"
+ "stosb\n\t"
+ "testb %%al,%%al\n\t"
+ "jne 1b\n\t"
+ "decl %2\n"
+ "rep\n\t"
+ "stosb\n"
+ "2:"
+ : "=&S" (d0), "=&D" (d1), "=&c" (d2), "=&a" (d3)
+ :"0" (src),"1" (dest),"2" (count) : "memory");
+ return dest;
+}
+
+strong_alias(__strncpy, strncpy)