Index: uspace/lib/posix/source/strings.c
===================================================================
--- uspace/lib/posix/source/strings.c	(revision 33c29521d96b892e096419a2fd8beb867e2596f6)
+++ uspace/lib/posix/source/strings.c	(revision 33c29521d96b892e096419a2fd8beb867e2596f6)
@@ -0,0 +1,187 @@
+/*
+ * Copyright (c) 2011 Jiri Zarevucky
+ * Copyright (c) 2011 Petr Koupy
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - 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.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+
+/** @addtogroup libposix
+ * @{
+ */
+/** @file Additional string manipulation.
+ */
+
+#define LIBPOSIX_INTERNAL
+
+#include "internal/common.h"
+#include "posix/strings.h"
+
+#include "posix/string.h"
+#include "posix/ctype.h"
+
+#include "libc/mem.h"
+
+/**
+ * Find first set bit (beginning with the least significant bit).
+ *
+ * @param i Integer in which to look for the first set bit.
+ * @return Index of first set bit. Bits are numbered starting at one.
+ */
+int posix_ffs(int i)
+{
+	if (i == 0) {
+		return 0;
+	}
+
+	int result = 0;
+
+	// XXX: assumes at most 32-bit int
+	if (!(i & 0xFFFF)) {
+		result |= 16;
+		i >>= 16;
+	}
+	if (!(i & 0xFF)) {
+		result |= 8;
+		i >>= 8;
+	}
+	if (!(i & 0xF)) {
+		result |= 4;
+		i >>= 4;
+	}
+	if (!(i & 0x3)) {
+		result |= 2;
+		i >>= 2;
+	}
+	if (!(i & 0x1)) {
+		result |= 1;
+	}
+
+	return result + 1;
+}
+
+/**
+ * Compare two strings (case-insensitive).
+ *
+ * @param s1 First string to be compared.
+ * @param s2 Second string to be compared.
+ * @return Difference of the first pair of inequal characters,
+ *     or 0 if strings have the same content.
+ */
+int posix_strcasecmp(const char *s1, const char *s2)
+{
+	return posix_strncasecmp(s1, s2, STR_NO_LIMIT);
+}
+
+/**
+ * Compare part of two strings (case-insensitive).
+ *
+ * @param s1 First string to be compared.
+ * @param s2 Second string to be compared.
+ * @param n Maximum number of characters to be compared.
+ * @return Difference of the first pair of inequal characters,
+ *     or 0 if strings have the same content.
+ */
+int posix_strncasecmp(const char *s1, const char *s2, size_t n)
+{
+	for (size_t i = 0; i < n; ++i) {
+		int cmp = tolower(s1[i]) - tolower(s2[i]);
+		if (cmp != 0) {
+			return cmp;
+		}
+		
+		if (s1[i] == 0) {
+			return 0;
+		}
+	}
+	
+	return 0;
+}
+
+/**
+ * Compare two memory areas.
+ *
+ * @param mem1 Pointer to the first area to compare.
+ * @param mem2 Pointer to the second area to compare.
+ * @param n Common size of both areas.
+ * @return If n is 0, return zero. If the areas match, return
+ *     zero. Otherwise return non-zero.
+ */
+int posix_bcmp(const void *mem1, const void *mem2, size_t n)
+{
+	return bcmp(mem1, mem2, n);
+}
+
+/**
+ * Copy bytes in memory with overlapping areas.
+ *
+ * @param src Source area.
+ * @param dest Destination area.
+ * @param n Number of bytes to copy.
+ */
+void posix_bcopy(const void *src, void *dest, size_t n)
+{
+	/* Note that memmove has different order of arguments. */
+	memmove(dest, src, n);
+}
+
+/**
+ * Reset bytes in memory area to zero.
+ *
+ * @param mem Memory area to be zeroed.
+ * @param n Number of bytes to reset.
+ */
+void posix_bzero(void *mem, size_t n)
+{
+	bzero(mem, n);
+}
+
+/**
+ * Scan string for a first occurence of a character.
+ *
+ * @param s String in which to look for the character.
+ * @param c Character to look for.
+ * @return Pointer to the specified character on success,
+ *     NULL pointer otherwise.
+ */
+char *posix_index(const char *s, int c)
+{
+	return posix_strchr(s, c);
+}
+
+/**
+ * Scan string for a last occurence of a character.
+ *
+ * @param s String in which to look for the character.
+ * @param c Character to look for.
+ * @return Pointer to the specified character on success,
+ *     NULL pointer otherwise.
+ */
+char *posix_rindex(const char *s, int c)
+{
+	return posix_strrchr(s, c);
+}
+
+/** @}
+ */