Initial revision

1 files changed, 99 insertions, 0 deletions

diff --git a/src/arch/i386/include/bits/string.h b/src/arch/i386/include/bits/string.h
new file mode 100644
index 000000000..3743d011e
--- /dev/null
+++ b/src/arch/i386/include/bits/string.h
@@ -0,0 +1,99 @@
+#ifndef ETHERBOOT_BITS_STRING_H
+#define ETHERBOOT_BITS_STRING_H
+/*
+ * Taken from Linux /usr/include/asm/string.h
+ * All except memcpy, memmove, memset and memcmp removed.
+ */
+
+/*
+ * 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.
+ */
+
+
+#define __HAVE_ARCH_MEMMOVE
+static inline void * memmove(void * dest,const void * src, size_t n)
+{
+int d0, d1, d2;
+if (dest<src)
+__asm__ __volatile__(
+	"cld\n\t"
+	"rep\n\t"
+	"movsb"
+	: "=&c" (d0), "=&S" (d1), "=&D" (d2)
+	:"0" (n),"1" (src),"2" (dest)
+	: "memory");
+else
+__asm__ __volatile__(
+	"std\n\t"
+	"rep\n\t"
+	"movsb\n\t"
+	"cld"
+	: "=&c" (d0), "=&S" (d1), "=&D" (d2)
+	:"0" (n),
+	 "1" (n-1+(const char *)src),
+	 "2" (n-1+(char *)dest)
+	:"memory");
+return dest;
+}
+
+#define __HAVE_ARCH_MEMSET
+static inline void *memset(void *s, int c,size_t count)
+{
+int d0, d1;
+__asm__ __volatile__(
+	"cld\n\t"
+	"rep\n\t"
+	"stosb"
+	: "=&c" (d0), "=&D" (d1)
+	:"a" (c),"1" (s),"0" (count)
+	:"memory");
+return s;
+}
+
+#define __HAVE_ARCH_STRNCMP
+static inline int strncmp(const char * cs,const char * ct,size_t count)
+{
+register int __res;
+int d0, d1, d2;
+__asm__ __volatile__(
+	"1:\tdecl %3\n\t"
+	"js 2f\n\t"
+	"lodsb\n\t"
+	"scasb\n\t"
+	"jne 3f\n\t"
+	"testb %%al,%%al\n\t"
+	"jne 1b\n"
+	"2:\txorl %%eax,%%eax\n\t"
+	"jmp 4f\n"
+	"3:\tsbbl %%eax,%%eax\n\t"
+	"orb $1,%%al\n"
+	"4:"
+		     :"=a" (__res), "=&S" (d0), "=&D" (d1), "=&c" (d2)
+		     :"1" (cs),"2" (ct),"3" (count));
+return __res;
+}
+
+#define __HAVE_ARCH_STRLEN
+static inline size_t strlen(const char * s)
+{
+int d0;
+register int __res;
+__asm__ __volatile__(
+	"repne\n\t"
+	"scasb\n\t"
+	"notl %0\n\t"
+	"decl %0"
+	:"=c" (__res), "=&D" (d0) :"1" (s),"a" (0), "0" (0xffffffff));
+return __res;
+}
+
+#endif /* ETHERBOOT_BITS_STRING_H */