Merge pull request #1528 from antonio-nino-diaz-arm/an/libc

libc: Cleanup library

21 files changed, 463 insertions, 826 deletions

diff --git a/lib/libc/abort.c b/lib/libc/abort.c
index 65ce4cca..c9d16ccc 100644
--- a/lib/libc/abort.c
+++ b/lib/libc/abort.c
@@ -7,10 +7,7 @@
 #include <debug.h>
 #include <stdlib.h>
 
-/*
- * This is a basic implementation. This could be improved.
- */
-void abort (void)
+void abort(void)
 {
 	ERROR("ABORT\n");
 	panic();
diff --git a/lib/libc/assert.c b/lib/libc/assert.c
index 97fab4b0..fa12cb6b 100644
--- a/lib/libc/assert.c
+++ b/lib/libc/assert.c
@@ -1,30 +1,32 @@
 /*
- * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
 #include <assert.h>
+#include <cdefs.h>
 #include <console.h>
 #include <debug.h>
 #include <platform.h>
+#include <stdio.h>
 
 /*
-* Only print the output if PLAT_LOG_LEVEL_ASSERT is higher or equal to
-* LOG_LEVEL_INFO, which is the default value for builds with DEBUG=1.
-*/
+ * Only print the output if PLAT_LOG_LEVEL_ASSERT is higher or equal to
+ * LOG_LEVEL_INFO, which is the default value for builds with DEBUG=1.
+ */
 
 #if PLAT_LOG_LEVEL_ASSERT >= LOG_LEVEL_VERBOSE
 void __assert(const char *file, unsigned int line, const char *assertion)
 {
-	tf_printf("ASSERT: %s:%d:%s\n", file, line, assertion);
+	printf("ASSERT: %s:%d:%s\n", file, line, assertion);
 	console_flush();
 	plat_panic_handler();
 }
 #elif PLAT_LOG_LEVEL_ASSERT >= LOG_LEVEL_INFO
 void __assert(const char *file, unsigned int line)
 {
-	tf_printf("ASSERT: %s:%d\n", file, line);
+	printf("ASSERT: %s:%d\n", file, line);
 	console_flush();
 	plat_panic_handler();
 }
diff --git a/lib/libc/libc.mk b/lib/libc/libc.mk
index ded3d745..554f36bb 100644
--- a/lib/libc/libc.mk
+++ b/lib/libc/libc.mk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -8,18 +8,20 @@ LIBC_SRCS	:=	$(addprefix lib/libc/,	\
 			abort.c				\
 			assert.c			\
 			exit.c				\
-			mem.c				\
+			memchr.c			\
+			memcmp.c			\
+			memcpy.c			\
+			memmove.c			\
+			memset.c			\
 			printf.c			\
 			putchar.c			\
 			puts.c				\
-			sscanf.c			\
+			snprintf.c			\
 			strchr.c			\
 			strcmp.c			\
 			strlen.c			\
 			strncmp.c			\
-			strnlen.c			\
-			subr_prf.c			\
-			timingsafe_bcmp.c)
+			strnlen.c)
 
 INCLUDES	+=	-Iinclude/lib/libc		\
-			-Iinclude/lib/libc/sys
+			-Iinclude/lib/libc/$(ARCH)	\
diff --git a/lib/libc/mem.c b/lib/libc/mem.c
deleted file mode 100644
index 65b62fde..00000000
--- a/lib/libc/mem.c
+++ /dev/null
@@ -1,97 +0,0 @@
-/*
- * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
- *
- * SPDX-License-Identifier: BSD-3-Clause
- */
-
-#include <stddef.h> /* size_t */
-
-/*
- * Fill @count bytes of memory pointed to by @dst with @val
- */
-void *memset(void *dst, int val, size_t count)
-{
-	char *ptr = dst;
-
-	while (count--)
-		*ptr++ = val;
-
-	return dst;
-}
-
-/*
- * Compare @len bytes of @s1 and @s2
- */
-int memcmp(const void *s1, const void *s2, size_t len)
-{
-	const unsigned char *s = s1;
-	const unsigned char *d = s2;
-	unsigned char sc;
-	unsigned char dc;
-
-	while (len--) {
-		sc = *s++;
-		dc = *d++;
-		if (sc - dc)
-			return (sc - dc);
-	}
-
-	return 0;
-}
-
-/*
- * Copy @len bytes from @src to @dst
- */
-void *memcpy(void *dst, const void *src, size_t len)
-{
-	const char *s = src;
-	char *d = dst;
-
-	while (len--)
-		*d++ = *s++;
-
-	return dst;
-}
-
-/*
- * Move @len bytes from @src to @dst
- */
-void *memmove(void *dst, const void *src, size_t len)
-{
-	/*
-	 * The following test makes use of unsigned arithmetic overflow to
-	 * more efficiently test the condition !(src <= dst && dst < str+len).
-	 * It also avoids the situation where the more explicit test would give
-	 * incorrect results were the calculation str+len to overflow (though
-	 * that issue is probably moot as such usage is probably undefined
-	 * behaviour and a bug anyway.
-	 */
-	if ((size_t)dst - (size_t)src >= len) {
-		/* destination not in source data, so can safely use memcpy */
-		return memcpy(dst, src, len);
-	} else {
-		/* copy backwards... */
-		const char *end = dst;
-		const char *s = (const char *)src + len;
-		char *d = (char *)dst + len;
-		while (d != end)
-			*--d = *--s;
-	}
-	return dst;
-}
-
-/*
- * Scan @len bytes of @src for value @c
- */
-void *memchr(const void *src, int c, size_t len)
-{
-	const char *s = src;
-
-	while (len--) {
-		if (*s == c)
-			return (void *) s;
-		s++;
-	}
-
-	return NULL;
-}
diff --git a/lib/libc/memchr.c b/lib/libc/memchr.c
new file mode 100644
index 00000000..2eba47c9
--- /dev/null
+++ b/lib/libc/memchr.c
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+
+void *memchr(const void *src, int c, size_t len)
+{
+	const char *s = src;
+
+	while (len--) {
+		if (*s == c)
+			return (void *) s;
+		s++;
+	}
+
+	return NULL;
+}
diff --git a/lib/libc/memcmp.c b/lib/libc/memcmp.c
new file mode 100644
index 00000000..a4c798b0
--- /dev/null
+++ b/lib/libc/memcmp.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+	const unsigned char *s = s1;
+	const unsigned char *d = s2;
+	unsigned char sc;
+	unsigned char dc;
+
+	while (len--) {
+		sc = *s++;
+		dc = *d++;
+		if (sc - dc)
+			return (sc - dc);
+	}
+
+	return 0;
+}
diff --git a/lib/libc/memcpy.c b/lib/libc/memcpy.c
new file mode 100644
index 00000000..fc0c9fe8
--- /dev/null
+++ b/lib/libc/memcpy.c
@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+
+void *memcpy(void *dst, const void *src, size_t len)
+{
+	const char *s = src;
+	char *d = dst;
+
+	while (len--)
+		*d++ = *s++;
+
+	return dst;
+}
diff --git a/lib/libc/memmove.c b/lib/libc/memmove.c
new file mode 100644
index 00000000..63acf267
--- /dev/null
+++ b/lib/libc/memmove.c
@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <string.h>
+
+void *memmove(void *dst, const void *src, size_t len)
+{
+	/*
+	 * The following test makes use of unsigned arithmetic overflow to
+	 * more efficiently test the condition !(src <= dst && dst < str+len).
+	 * It also avoids the situation where the more explicit test would give
+	 * incorrect results were the calculation str+len to overflow (though
+	 * that issue is probably moot as such usage is probably undefined
+	 * behaviour and a bug anyway.
+	 */
+	if ((size_t)dst - (size_t)src >= len) {
+		/* destination not in source data, so can safely use memcpy */
+		return memcpy(dst, src, len);
+	} else {
+		/* copy backwards... */
+		const char *end = dst;
+		const char *s = (const char *)src + len;
+		char *d = (char *)dst + len;
+		while (d != end)
+			*--d = *--s;
+	}
+	return dst;
+}
diff --git a/lib/libc/memset.c b/lib/libc/memset.c
new file mode 100644
index 00000000..03aa8096
--- /dev/null
+++ b/lib/libc/memset.c
@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+
+void *memset(void *dst, int val, size_t count)
+{
+	char *ptr = dst;
+
+	while (count--)
+		*ptr++ = val;
+
+	return dst;
+}
diff --git a/lib/libc/printf.c b/lib/libc/printf.c
index f6156414..4f4a722f 100644
--- a/lib/libc/printf.c
+++ b/lib/libc/printf.c
@@ -1,36 +1,190 @@
 /*
- * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
-
-#include <stdio.h>
+#include <assert.h>
+#include <debug.h>
 #include <stdarg.h>
+#include <stdint.h>
 
-/* Choose max of 128 chars for now. */
-#define PRINT_BUFFER_SIZE 128
-int printf(const char *fmt, ...)
+/***********************************************************
+ * The printf implementation for all BL stages
+ ***********************************************************/
+
+#define get_num_va_args(_args, _lcount) \
+	(((_lcount) > 1) ? va_arg(_args, long long int) :	\
+	((_lcount) ? va_arg(_args, long int) : va_arg(_args, int)))
+
+#define get_unum_va_args(_args, _lcount) \
+	(((_lcount) > 1) ? va_arg(_args, unsigned long long int) :	\
+	((_lcount) ? va_arg(_args, unsigned long int) : va_arg(_args, unsigned int)))
+
+static int string_print(const char *str)
 {
-	va_list args;
-	char buf[PRINT_BUFFER_SIZE];
-	int count;
+	int count = 0;
+
+	assert(str);
+
+	while (*str) {
+		putchar(*str++);
+		count++;
+	}
+
+	return count;
+}
 
-	va_start(args, fmt);
-	vsnprintf(buf, sizeof(buf) - 1, fmt, args);
-	va_end(args);
+static int unsigned_num_print(unsigned long long int unum, unsigned int radix,
+			      char padc, int padn)
+{
+	/* Just need enough space to store 64 bit decimal integer */
+	unsigned char num_buf[20];
+	int i = 0, rem, count = 0;
 
-	/* Use putchar directly as 'puts()' adds a newline. */
-	buf[PRINT_BUFFER_SIZE - 1] = '\0';
-	count = 0;
-	while (buf[count])
-	{
-		if (putchar(buf[count]) != EOF) {
+	do {
+		rem = unum % radix;
+		if (rem < 0xa)
+			num_buf[i++] = '0' + rem;
+		else
+			num_buf[i++] = 'a' + (rem - 0xa);
+	} while (unum /= radix);
+
+	if (padn > 0) {
+		while (i < padn--) {
+			putchar(padc);
 			count++;
-		} else {
-			count = EOF;
-			break;
 		}
 	}
 
+	while (--i >= 0) {
+		putchar(num_buf[i]);
+		count++;
+	}
+
+	return count;
+}
+
+/*******************************************************************
+ * Reduced format print for Trusted firmware.
+ * The following type specifiers are supported by this print
+ * %x - hexadecimal format
+ * %s - string format
+ * %d or %i - signed decimal format
+ * %u - unsigned decimal format
+ * %p - pointer format
+ *
+ * The following length specifiers are supported by this print
+ * %l - long int (64-bit on AArch64)
+ * %ll - long long int (64-bit on AArch64)
+ * %z - size_t sized integer formats (64 bit on AArch64)
+ *
+ * The following padding specifiers are supported by this print
+ * %0NN - Left-pad the number with 0s (NN is a decimal number)
+ *
+ * The print exits on all other formats specifiers other than valid
+ * combinations of the above specifiers.
+ *******************************************************************/
+int vprintf(const char *fmt, va_list args)
+{
+	int l_count;
+	long long int num;
+	unsigned long long int unum;
+	char *str;
+	char padc = 0; /* Padding character */
+	int padn; /* Number of characters to pad */
+	int count = 0; /* Number of printed characters */
+
+	while (*fmt) {
+		l_count = 0;
+		padn = 0;
+
+		if (*fmt == '%') {
+			fmt++;
+			/* Check the format specifier */
+loop:
+			switch (*fmt) {
+			case 'i': /* Fall through to next one */
+			case 'd':
+				num = get_num_va_args(args, l_count);
+				if (num < 0) {
+					putchar('-');
+					unum = (unsigned long long int)-num;
+					padn--;
+				} else
+					unum = (unsigned long long int)num;
+
+				count += unsigned_num_print(unum, 10,
+							    padc, padn);
+				break;
+			case 's':
+				str = va_arg(args, char *);
+				count += string_print(str);
+				break;
+			case 'p':
+				unum = (uintptr_t)va_arg(args, void *);
+				if (unum) {
+					count += string_print("0x");
+					padn -= 2;
+				}
+
+				count += unsigned_num_print(unum, 16,
+							    padc, padn);
+				break;
+			case 'x':
+				unum = get_unum_va_args(args, l_count);
+				count += unsigned_num_print(unum, 16,
+							    padc, padn);
+				break;
+			case 'z':
+				if (sizeof(size_t) == 8)
+					l_count = 2;
+
+				fmt++;
+				goto loop;
+			case 'l':
+				l_count++;
+				fmt++;
+				goto loop;
+			case 'u':
+				unum = get_unum_va_args(args, l_count);
+				count += unsigned_num_print(unum, 10,
+							    padc, padn);
+				break;
+			case '0':
+				padc = '0';
+				padn = 0;
+				fmt++;
+
+				while (1) {
+					char ch = *fmt;
+					if (ch < '0' || ch > '9') {
+						goto loop;
+					}
+					padn = (padn * 10) + (ch - '0');
+					fmt++;
+				}
+			default:
+				/* Exit on any other format specifier */
+				return -1;
+			}
+			fmt++;
+			continue;
+		}
+		putchar(*fmt++);
+		count++;
+	}
+
+	return count;
+}
+
+int printf(const char *fmt, ...)
+{
+	int count;
+	va_list va;
+
+	va_start(va, fmt);
+	count = vprintf(fmt, va);
+	va_end(va);
+
 	return count;
 }
diff --git a/lib/libc/putchar.c b/lib/libc/putchar.c
index 8265667b..0beb625b 100644
--- a/lib/libc/putchar.c
+++ b/lib/libc/putchar.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -7,11 +7,6 @@
 #include <stdio.h>
 #include <console.h>
 
-/* Putchar() should either return the character printed or EOF in case of error.
- * Our current console_putc() function assumes success and returns the
- * character. Write all other printing functions in terms of putchar(), if
- * possible, so they all benefit when this is improved.
- */
 int putchar(int c)
 {
 	int res;
diff --git a/lib/libc/puts.c b/lib/libc/puts.c
index 284cf8c5..717b5228 100644
--- a/lib/libc/puts.c
+++ b/lib/libc/puts.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -9,15 +9,13 @@
 int puts(const char *s)
 {
 	int count = 0;
-	while(*s) {
+
+	while (*s) {
 		if (putchar(*s++) == EOF)
 			return EOF;
 		count++;
 	}
 
-	/* According to the puts(3) manpage, the function should write a
-	 * trailing newline.
-	 */
 	if (putchar('\n') == EOF)
 		return EOF;
 
diff --git a/lib/libc/snprintf.c b/lib/libc/snprintf.c
new file mode 100644
index 00000000..0738a869
--- /dev/null
+++ b/lib/libc/snprintf.c
@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <debug.h>
+#include <platform.h>
+#include <stdarg.h>
+
+static void string_print(char **s, size_t n, size_t *chars_printed,
+			 const char *str)
+{
+	while (*str) {
+		if (*chars_printed < n)
+			*(*s)++ = *str;
+		(*chars_printed)++;
+		str++;
+	}
+}
+
+static void unsigned_dec_print(char **s, size_t n, size_t *chars_printed,
+			       unsigned int unum)
+{
+	/* Enough for a 32-bit unsigned decimal integer (4294967295). */
+	unsigned char num_buf[10];
+	int i = 0, rem;
+
+	do {
+		rem = unum % 10;
+		num_buf[i++] = '0' + rem;
+	} while (unum /= 10);
+
+	while (--i >= 0) {
+		if (*chars_printed < n)
+			*(*s)++ = num_buf[i];
+		(*chars_printed)++;
+	}
+}
+
+/*******************************************************************
+ * Reduced snprintf to be used for Trusted firmware.
+ * The following type specifiers are supported:
+ *
+ * %d or %i - signed decimal format
+ * %s - string format
+ * %u - unsigned decimal format
+ *
+ * The function panics on all other formats specifiers.
+ *
+ * It returns the number of characters that would be written if the
+ * buffer was big enough. If it returns a value lower than n, the
+ * whole string has been written.
+ *******************************************************************/
+int snprintf(char *s, size_t n, const char *fmt, ...)
+{
+	va_list args;
+	int num;
+	unsigned int unum;
+	char *str;
+	size_t chars_printed = 0;
+
+	if (n == 1) {
+		/* Buffer is too small to actually write anything else. */
+		*s = '\0';
+		n = 0;
+	} else if (n >= 2) {
+		/* Reserve space for the terminator character. */
+		n--;
+	}
+
+	va_start(args, fmt);
+	while (*fmt) {
+
+		if (*fmt == '%') {
+			fmt++;
+			/* Check the format specifier. */
+			switch (*fmt) {
+			case 'i':
+			case 'd':
+				num = va_arg(args, int);
+
+				if (num < 0) {
+					if (chars_printed < n)
+						*s++ = '-';
+					chars_printed++;
+
+					unum = (unsigned int)-num;
+				} else {
+					unum = (unsigned int)num;
+				}
+
+				unsigned_dec_print(&s, n, &chars_printed, unum);
+				break;
+			case 's':
+				str = va_arg(args, char *);
+				string_print(&s, n, &chars_printed, str);
+				break;
+			case 'u':
+				unum = va_arg(args, unsigned int);
+				unsigned_dec_print(&s, n, &chars_printed, unum);
+				break;
+			default:
+				/* Panic on any other format specifier. */
+				ERROR("snprintf: specifier with ASCII code '%d' not supported.",
+				      *fmt);
+				plat_panic_handler();
+			}
+			fmt++;
+			continue;
+		}
+
+		if (chars_printed < n)
+			*s++ = *fmt;
+		fmt++;
+		chars_printed++;
+	}
+
+	va_end(args);
+
+	if (n > 0)
+		*s = '\0';
+
+	return chars_printed;
+}
diff --git a/lib/libc/sscanf.c b/lib/libc/sscanf.c
deleted file mode 100644
index a5876cff..00000000
--- a/lib/libc/sscanf.c
+++ /dev/null
@@ -1,27 +0,0 @@
-/*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
- *
- * SPDX-License-Identifier: BSD-3-Clause
- */
-
-#include <stdio.h>
-#include <sys/cdefs.h>
-
-/*
- * TODO: This is not a real implementation of the sscanf() function. It just
- * returns the number of expected arguments based on the number of '%' found
- * in the format string.
- */
-int
-sscanf(const char *__restrict str, char const *__restrict fmt, ...)
-{
-	int ret = 0;
-
-	while (*fmt != '\0') {
-		if (*fmt++ == '%') {
-			ret++;
-		}
-	}
-
-	return ret;
-}
diff --git a/lib/libc/strchr.c b/lib/libc/strchr.c
index 4247dcd3..d94bb9e0 100644
--- a/lib/libc/strchr.c
+++ b/lib/libc/strchr.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
  * Copyright (c) 1990, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -10,7 +12,7 @@
  * 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.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -28,11 +30,10 @@
  */
 
 /*
- * Portions copyright (c) 2013-2014, ARM Limited and Contributors.
+ * Portions copyright (c) 2018, ARM Limited and Contributors.
  * All rights reserved.
  */
 
-#include <sys/cdefs.h>
 #include <stddef.h>
 #include <string.h>
 
diff --git a/lib/libc/strcmp.c b/lib/libc/strcmp.c
index bb86e0f2..b742f9b9 100644
--- a/lib/libc/strcmp.c
+++ b/lib/libc/strcmp.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
  * Copyright (c) 1990, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -13,7 +15,7 @@
  * 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.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -31,12 +33,10 @@
  */
 
 /*
- * Portions copyright (c) 2014, ARM Limited and Contributors.
+ * Portions copyright (c) 2018, ARM Limited and Contributors.
  * All rights reserved.
  */
 
-#include <sys/cdefs.h>
-#include <sys/ctype.h>
 #include <string.h>
 
 /*
@@ -47,20 +47,6 @@ strcmp(const char *s1, const char *s2)
 {
 	while (*s1 == *s2++)
 		if (*s1++ == '\0')
-			return 0;
-	return *(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1);
-}
-
-int
-strcasecmp(const char *s1, const char *s2)
-{
-	const unsigned char *us1 = (const unsigned char *)s1;
-	const unsigned char *us2 = (const unsigned char *)s2;
-
-	while (tolower(*us1) == tolower(*us2)) {
-		if (*us1++ == '\0')
-			return 0;
-		us2++;
-	}
-	return tolower(*us1) - tolower(*us2);
+			return (0);
+	return (*(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1));
 }
diff --git a/lib/libc/strlen.c b/lib/libc/strlen.c
index 23c3d392..3c276300 100644
--- a/lib/libc/strlen.c
+++ b/lib/libc/strlen.c
@@ -1,44 +1,17 @@
-/*-
- * Copyright (c) 1990, 1993
- *	The Regents of the University of California.  All rights reserved.
- *
- * 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.
- * 4. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
- */
-
 /*
- * Portions copyright (c) 2009-2014, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#include <stddef.h>
+#include <string.h>
 
-size_t
-strlen(str)
-	const char *str;
+size_t strlen(const char *s)
 {
-	register const char *s;
+	const char *cursor = s;
+
+	while (*cursor)
+		cursor++;
 
-	for (s = str; *s; ++s);
-	return(s - str);
+	return cursor - s;
 }
diff --git a/lib/libc/strncmp.c b/lib/libc/strncmp.c
index f45f4a22..ce9e5ed4 100644
--- a/lib/libc/strncmp.c
+++ b/lib/libc/strncmp.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
  * Copyright (c) 1989, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -10,7 +12,7 @@
  * 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.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -28,11 +30,10 @@
  */
 
 /*
- * Portions copyright (c) 2014, ARM Limited and Contributors.
+ * Portions copyright (c) 2018, ARM Limited and Contributors.
  * All rights reserved.
  */
 
-#include <sys/cdefs.h>
 #include <string.h>
 
 int
@@ -40,7 +41,7 @@ strncmp(const char *s1, const char *s2, size_t n)
 {
 
 	if (n == 0)
-		return 0;
+		return (0);
 	do {
 		if (*s1 != *s2++)
 			return (*(const unsigned char *)s1 -
@@ -48,5 +49,5 @@ strncmp(const char *s1, const char *s2, size_t n)
 		if (*s1++ == '\0')
 			break;
 	} while (--n != 0);
-	return 0;
+	return (0);
 }
diff --git a/lib/libc/strnlen.c b/lib/libc/strnlen.c
index d48502bd..b944e95b 100644
--- a/lib/libc/strnlen.c
+++ b/lib/libc/strnlen.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
  * Copyright (c) 2009 David Schultz <das@FreeBSD.org>
  * All rights reserved.
  *
@@ -25,11 +27,10 @@
  */
 
 /*
- * Portions copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ * Portions copyright (c) 2018, ARM Limited and Contributors.
+ * All rights reserved.
  */
 
-#include <sys/cdefs.h>
-
 #include <string.h>
 
 size_t
diff --git a/lib/libc/subr_prf.c b/lib/libc/subr_prf.c
deleted file mode 100644
index c1035624..00000000
--- a/lib/libc/subr_prf.c
+++ /dev/null
@@ -1,548 +0,0 @@
-/*-
- * Copyright (c) 1986, 1988, 1991, 1993
- *	The Regents of the University of California.  All rights reserved.
- * (c) UNIX System Laboratories, Inc.
- * All or some portions of this file are derived from material licensed
- * to the University of California by American Telephone and Telegraph
- * Co. or Unix System Laboratories, Inc. and are reproduced herein with
- * the permission of UNIX System Laboratories, Inc.
- *
- * 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.
- * 4. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
- *
- *	@(#)subr_prf.c	8.3 (Berkeley) 1/21/94
- */
-
-/*
- * Portions copyright (c) 2009-2014, ARM Limited and Contributors.
- * All rights reserved.
- */
-
-#include <stdio.h>
-#include <stdint.h>
-#include <stdarg.h>
-#include <stddef.h>
-#include <string.h>
-#include <ctype.h>
-
-typedef unsigned char u_char;
-typedef unsigned int u_int;
-typedef int64_t quad_t;
-typedef uint64_t u_quad_t;
-typedef unsigned long u_long;
-typedef unsigned short u_short;
-
-static inline int imax(int a, int b) { return (a > b ? a : b); }
-
-/*
- * Note that stdarg.h and the ANSI style va_start macro is used for both
- * ANSI and traditional C compilers.
- */
-
-#define TOCONS	0x01
-#define TOTTY	0x02
-#define TOLOG	0x04
-
-/* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
-#define MAXNBUF	(sizeof(intmax_t) * 8 + 1)
-
-struct putchar_arg {
-	int	flags;
-	int	pri;
-	struct	tty *tty;
-	char	*p_bufr;
-	size_t	n_bufr;
-	char	*p_next;
-	size_t	remain;
-};
-
-struct snprintf_arg {
-	char	*str;
-	size_t	remain;
-};
-
-extern	int log_open;
-
-static char *ksprintn(char *nbuf, uintmax_t num, int base, int *len, int upper);
-static void  snprintf_func(int ch, void *arg);
-static int kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap);
-
-int vsnprintf(char *str, size_t size, const char *format, va_list ap);
-
-static char const hex2ascii_data[] = "0123456789abcdefghijklmnopqrstuvwxyz";
-#define hex2ascii(hex) (hex2ascii_data[hex])
-
-/*
- * Scaled down version of sprintf(3).
- */
-int
-sprintf(char *buf, const char *cfmt, ...)
-{
-	int retval;
-	va_list ap;
-
-	va_start(ap, cfmt);
-	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
-	buf[retval] = '\0';
-	va_end(ap);
-	return (retval);
-}
-
-/*
- * Scaled down version of vsprintf(3).
- */
-int
-vsprintf(char *buf, const char *cfmt, va_list ap)
-{
-	int retval;
-
-	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
-	buf[retval] = '\0';
-	return (retval);
-}
-
-/*
- * Scaled down version of snprintf(3).
- */
-int
-snprintf(char *str, size_t size, const char *format, ...)
-{
-	int retval;
-	va_list ap;
-
-	va_start(ap, format);
-	retval = vsnprintf(str, size, format, ap);
-	va_end(ap);
-	return(retval);
-}
-
-/*
- * Scaled down version of vsnprintf(3).
- */
-int
-vsnprintf(char *str, size_t size, const char *format, va_list ap)
-{
-	struct snprintf_arg info;
-	int retval;
-
-	info.str = str;
-	info.remain = size;
-	retval = kvprintf(format, snprintf_func, &info, 10, ap);
-	if (info.remain >= 1)
-		*info.str++ = '\0';
-	return (retval);
-}
-
-static void
-snprintf_func(int ch, void *arg)
-{
-	struct snprintf_arg *const info = arg;
-
-	if (info->remain >= 2) {
-		*info->str++ = ch;
-		info->remain--;
-	}
-}
-
-
-/*
- * Kernel version which takes radix argument vsnprintf(3).
- */
-int
-vsnrprintf(char *str, size_t size, int radix, const char *format, va_list ap)
-{
-	struct snprintf_arg info;
-	int retval;
-
-	info.str = str;
-	info.remain = size;
-	retval = kvprintf(format, snprintf_func, &info, radix, ap);
-	if (info.remain >= 1)
-		*info.str++ = '\0';
-	return (retval);
-}
-
-
-/*
- * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
- * order; return an optional length and a pointer to the last character
- * written in the buffer (i.e., the first character of the string).
- * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
- */
-static char *
-ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
-{
-	char *p, c;
-
-	p = nbuf;
-	*p = '\0';
-	do {
-		c = hex2ascii(num % base);
-		*++p = upper ? toupper(c) : c;
-	} while (num /= base);
-	if (lenp)
-		*lenp = p - nbuf;
-	return (p);
-}
-
-/*
- * Scaled down version of printf(3).
- *
- * Two additional formats:
- *
- * The format %b is supported to decode error registers.
- * Its usage is:
- *
- *	printf("reg=%b\n", regval, "<base><arg>*");
- *
- * where <base> is the output base expressed as a control character, e.g.
- * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
- * the first of which gives the bit number to be inspected (origin 1), and
- * the next characters (up to a control character, i.e. a character <= 32),
- * give the name of the register.  Thus:
- *
- *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
- *
- * would produce output:
- *
- *	reg=3<BITTWO,BITONE>
- *
- * XXX:  %D  -- Hexdump, takes pointer and separator string:
- *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
- *		("%*D", len, ptr, " " -> XX XX XX XX ...
- */
-int
-kvprintf(char const *fmt, void (*func)(int, void*), void *arg, int radix, va_list ap)
-{
-#define PCHAR(c) {int cc=(c); if (func) (*func)(cc,arg); else *d++ = cc; retval++; }
-	char nbuf[MAXNBUF];
-	char *d;
-	const char *p, *percent, *q;
-	u_char *up;
-	int ch, n;
-	uintmax_t num;
-	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
-	int cflag, hflag, jflag, tflag, zflag;
-	int dwidth, upper;
-	char padc;
-	int stop = 0, retval = 0;
-
-	num = 0;
-	if (!func)
-		d = (char *) arg;
-	else
-		d = NULL;
-
-	if (fmt == NULL)
-		fmt = "(fmt null)\n";
-
-	if (radix < 2 || radix > 36)
-		radix = 10;
-
-	for (;;) {
-		padc = ' ';
-		width = 0;
-		while ((ch = (u_char)*fmt++) != '%' || stop) {
-			if (ch == '\0')
-				return (retval);
-			PCHAR(ch);
-		}
-		percent = fmt - 1;
-		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
-		sign = 0; dot = 0; dwidth = 0; upper = 0;
-		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
-reswitch:	switch (ch = (u_char)*fmt++) {
-		case '.':
-			dot = 1;
-			goto reswitch;
-		case '#':
-			sharpflag = 1;
-			goto reswitch;
-		case '+':
-			sign = 1;
-			goto reswitch;
-		case '-':
-			ladjust = 1;
-			goto reswitch;
-		case '%':
-			PCHAR(ch);
-			break;
-		case '*':
-			if (!dot) {
-				width = va_arg(ap, int);
-				if (width < 0) {
-					ladjust = !ladjust;
-					width = -width;
-				}
-			} else {
-				dwidth = va_arg(ap, int);
-			}
-			goto reswitch;
-		case '0':
-			if (!dot) {
-				padc = '0';
-				goto reswitch;
-			}
-		case '1': case '2': case '3': case '4':
-		case '5': case '6': case '7': case '8': case '9':
-				for (n = 0;; ++fmt) {
-					n = n * 10 + ch - '0';
-					ch = *fmt;
-					if (ch < '0' || ch > '9')
-						break;
-				}
-			if (dot)
-				dwidth = n;
-			else
-				width = n;
-			goto reswitch;
-		case 'b':
-			num = (u_int)va_arg(ap, int);
-			p = va_arg(ap, char *);
-			for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
-				PCHAR(*q--);
-
-			if (num == 0)
-				break;
-
-			for (tmp = 0; *p;) {
-				n = *p++;
-				if (num & (1 << (n - 1))) {
-					PCHAR(tmp ? ',' : '<');
-					for (; (n = *p) > ' '; ++p)
-						PCHAR(n);
-					tmp = 1;
-				} else
-					for (; *p > ' '; ++p)
-						continue;
-			}
-			if (tmp)
-				PCHAR('>');
-			break;
-		case 'c':
-			PCHAR(va_arg(ap, int));
-			break;
-		case 'D':
-			up = va_arg(ap, u_char *);
-			p = va_arg(ap, char *);
-			if (!width)
-				width = 16;
-			while(width--) {
-				PCHAR(hex2ascii(*up >> 4));
-				PCHAR(hex2ascii(*up & 0x0f));
-				up++;
-				if (width)
-					for (q=p;*q;q++)
-						PCHAR(*q);
-			}
-			break;
-		case 'd':
-		case 'i':
-			base = 10;
-			sign = 1;
-			goto handle_sign;
-		case 'h':
-			if (hflag) {
-				hflag = 0;
-				cflag = 1;
-			} else
-				hflag = 1;
-			goto reswitch;
-		case 'j':
-			jflag = 1;
-			goto reswitch;
-		case 'l':
-			if (lflag) {
-				lflag = 0;
-				qflag = 1;
-			} else
-				lflag = 1;
-			goto reswitch;
-		case 'n':
-			if (jflag)
-				*(va_arg(ap, intmax_t *)) = retval;
-			else if (qflag)
-				*(va_arg(ap, quad_t *)) = retval;
-			else if (lflag)
-				*(va_arg(ap, long *)) = retval;
-			else if (zflag)
-				*(va_arg(ap, size_t *)) = retval;
-			else if (hflag)
-				*(va_arg(ap, short *)) = retval;
-			else if (cflag)
-				*(va_arg(ap, char *)) = retval;
-			else
-				*(va_arg(ap, int *)) = retval;
-			break;
-		case 'o':
-			base = 8;
-			goto handle_nosign;
-		case 'p':
-			base = 16;
-			sharpflag = (width == 0);
-			sign = 0;
-			num = (uintptr_t)va_arg(ap, void *);
-			goto number;
-		case 'q':
-			qflag = 1;
-			goto reswitch;
-		case 'r':
-			base = radix;
-			if (sign)
-				goto handle_sign;
-			goto handle_nosign;
-		case 's':
-			p = va_arg(ap, char *);
-			if (p == NULL)
-				p = "(null)";
-			if (!dot)
-				n = strlen (p);
-			else
-				for (n = 0; n < dwidth && p[n]; n++)
-					continue;
-
-			width -= n;
-
-			if (!ladjust && width > 0)
-				while (width--)
-					PCHAR(padc);
-			while (n--)
-				PCHAR(*p++);
-			if (ladjust && width > 0)
-				while (width--)
-					PCHAR(padc);
-			break;
-		case 't':
-			tflag = 1;
-			goto reswitch;
-		case 'u':
-			base = 10;
-			goto handle_nosign;
-		case 'X':
-			upper = 1;
-		case 'x':
-			base = 16;
-			goto handle_nosign;
-		case 'y':
-			base = 16;
-			sign = 1;
-			goto handle_sign;
-		case 'z':
-			zflag = 1;
-			goto reswitch;
-handle_nosign:
-			sign = 0;
-			if (jflag)
-				num = va_arg(ap, uintmax_t);
-			else if (qflag)
-				num = va_arg(ap, u_quad_t);
-			else if (tflag)
-				num = va_arg(ap, ptrdiff_t);
-			else if (lflag)
-				num = va_arg(ap, u_long);
-			else if (zflag)
-				num = va_arg(ap, size_t);
-			else if (hflag)
-				num = (u_short)va_arg(ap, int);
-			else if (cflag)
-				num = (u_char)va_arg(ap, int);
-			else
-				num = va_arg(ap, u_int);
-			goto number;
-handle_sign:
-			if (jflag)
-				num = va_arg(ap, intmax_t);
-			else if (qflag)
-				num = va_arg(ap, quad_t);
-			else if (tflag)
-				num = va_arg(ap, ptrdiff_t);
-			else if (lflag)
-				num = va_arg(ap, long);
-			else if (zflag)
-				num = va_arg(ap, ssize_t);
-			else if (hflag)
-				num = (short)va_arg(ap, int);
-			else if (cflag)
-				num = (char)va_arg(ap, int);
-			else
-				num = va_arg(ap, int);
-number:
-			if (sign && (intmax_t)num < 0) {
-				neg = 1;
-				num = -(intmax_t)num;
-			}
-			p = ksprintn(nbuf, num, base, &n, upper);
-			tmp = 0;
-			if (sharpflag && num != 0) {
-				if (base == 8)
-					tmp++;
-				else if (base == 16)
-					tmp += 2;
-			}
-			if (neg)
-				tmp++;
-
-			if (!ladjust && padc == '0')
-				dwidth = width - tmp;
-			width -= tmp + imax(dwidth, n);
-			dwidth -= n;
-			if (!ladjust)
-				while (width-- > 0)
-					PCHAR(' ');
-			if (neg)
-				PCHAR('-');
-			if (sharpflag && num != 0) {
-				if (base == 8) {
-					PCHAR('0');
-				} else if (base == 16) {
-					PCHAR('0');
-					PCHAR('x');
-				}
-			}
-			while (dwidth-- > 0)
-				PCHAR('0');
-
-			while (*p)
-				PCHAR(*p--);
-
-			if (ladjust)
-				while (width-- > 0)
-					PCHAR(' ');
-
-			break;
-		default:
-			while (percent < fmt)
-				PCHAR(*percent++);
-			/*
-			 * Since we ignore an formatting argument it is no 
-			 * longer safe to obey the remaining formatting
-			 * arguments as the arguments will no longer match
-			 * the format specs.
-			 */
-			stop = 1;
-			break;
-		}
-	}
-#undef PCHAR
-}
diff --git a/lib/libc/timingsafe_bcmp.c b/lib/libc/timingsafe_bcmp.c
deleted file mode 100644
index d0981580..00000000
--- a/lib/libc/timingsafe_bcmp.c
+++ /dev/null
@@ -1,36 +0,0 @@
-/*	$OpenBSD: timingsafe_bcmp.c,v 1.3 2015/08/31 02:53:57 guenther Exp $	*/
-/*
- * Copyright (c) 2010 Damien Miller.  All rights reserved.
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include <string.h>
-
-int __timingsafe_bcmp(const void *, const void *, size_t);
-
-int
-__timingsafe_bcmp(const void *b1, const void *b2, size_t n)
-{
-	const unsigned char *p1 = b1, *p2 = b2;
-	int ret = 0;
-
-	for (; n > 0; n--)
-		ret |= *p1++ ^ *p2++;
-	return (ret != 0);
-}
-
-__weak_reference(__timingsafe_bcmp, timingsafe_bcmp);