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path: root/target/linux/generic-2.6/patches-2.6.28/981-vsprintf_backport.patch
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--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -170,6 +170,8 @@ int strict_strtoul(const char *cp, unsig
 		return -EINVAL;
 
 	val = simple_strtoul(cp, &tail, base);
+	if (tail == cp)
+		return -EINVAL;
 	if ((*tail == '\0') ||
 		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
 		*res = val;
@@ -241,6 +243,8 @@ int strict_strtoull(const char *cp, unsi
 		return -EINVAL;
 
 	val = simple_strtoull(cp, &tail, base);
+	if (tail == cp)
+		return -EINVAL;
 	if ((*tail == '\0') ||
 		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
 		*res = val;
@@ -392,7 +396,38 @@ static noinline char* put_dec(char *buf,
 #define SMALL	32		/* Must be 32 == 0x20 */
 #define SPECIAL	64		/* 0x */
 
-static char *number(char *buf, char *end, unsigned long long num, int base, int size, int precision, int type)
+enum format_type {
+	FORMAT_TYPE_NONE, /* Just a string part */
+	FORMAT_TYPE_WIDTH,
+	FORMAT_TYPE_PRECISION,
+	FORMAT_TYPE_CHAR,
+	FORMAT_TYPE_STR,
+	FORMAT_TYPE_PTR,
+	FORMAT_TYPE_PERCENT_CHAR,
+	FORMAT_TYPE_INVALID,
+	FORMAT_TYPE_LONG_LONG,
+	FORMAT_TYPE_ULONG,
+	FORMAT_TYPE_LONG,
+	FORMAT_TYPE_USHORT,
+	FORMAT_TYPE_SHORT,
+	FORMAT_TYPE_UINT,
+	FORMAT_TYPE_INT,
+	FORMAT_TYPE_NRCHARS,
+	FORMAT_TYPE_SIZE_T,
+	FORMAT_TYPE_PTRDIFF
+};
+
+struct printf_spec {
+	enum format_type	type;
+	int			flags;		/* flags to number() */
+	int			field_width;	/* width of output field */
+	int			base;
+	int			precision;	/* # of digits/chars */
+	int			qualifier;
+};
+
+static char *number(char *buf, char *end, unsigned long long num,
+			struct printf_spec spec)
 {
 	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
 	static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
@@ -400,32 +435,32 @@ static char *number(char *buf, char *end
 	char tmp[66];
 	char sign;
 	char locase;
-	int need_pfx = ((type & SPECIAL) && base != 10);
+	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 	int i;
 
 	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
 	 * produces same digits or (maybe lowercased) letters */
-	locase = (type & SMALL);
-	if (type & LEFT)
-		type &= ~ZEROPAD;
+	locase = (spec.flags & SMALL);
+	if (spec.flags & LEFT)
+		spec.flags &= ~ZEROPAD;
 	sign = 0;
-	if (type & SIGN) {
+	if (spec.flags & SIGN) {
 		if ((signed long long) num < 0) {
 			sign = '-';
 			num = - (signed long long) num;
-			size--;
-		} else if (type & PLUS) {
+			spec.field_width--;
+		} else if (spec.flags & PLUS) {
 			sign = '+';
-			size--;
-		} else if (type & SPACE) {
+			spec.field_width--;
+		} else if (spec.flags & SPACE) {
 			sign = ' ';
-			size--;
+			spec.field_width--;
 		}
 	}
 	if (need_pfx) {
-		size--;
-		if (base == 16)
-			size--;
+		spec.field_width--;
+		if (spec.base == 16)
+			spec.field_width--;
 	}
 
 	/* generate full string in tmp[], in reverse order */
@@ -437,10 +472,10 @@ static char *number(char *buf, char *end
 		tmp[i++] = (digits[do_div(num,base)] | locase);
 	} while (num != 0);
 	*/
-	else if (base != 10) { /* 8 or 16 */
-		int mask = base - 1;
+	else if (spec.base != 10) { /* 8 or 16 */
+		int mask = spec.base - 1;
 		int shift = 3;
-		if (base == 16) shift = 4;
+		if (spec.base == 16) shift = 4;
 		do {
 			tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
 			num >>= shift;
@@ -450,12 +485,12 @@ static char *number(char *buf, char *end
 	}
 
 	/* printing 100 using %2d gives "100", not "00" */
-	if (i > precision)
-		precision = i;
+	if (i > spec.precision)
+		spec.precision = i;
 	/* leading space padding */
-	size -= precision;
-	if (!(type & (ZEROPAD+LEFT))) {
-		while(--size >= 0) {
+	spec.field_width -= spec.precision;
+	if (!(spec.flags & (ZEROPAD+LEFT))) {
+		while(--spec.field_width >= 0) {
 			if (buf < end)
 				*buf = ' ';
 			++buf;
@@ -472,23 +507,23 @@ static char *number(char *buf, char *end
 		if (buf < end)
 			*buf = '0';
 		++buf;
-		if (base == 16) {
+		if (spec.base == 16) {
 			if (buf < end)
 				*buf = ('X' | locase);
 			++buf;
 		}
 	}
 	/* zero or space padding */
-	if (!(type & LEFT)) {
-		char c = (type & ZEROPAD) ? '0' : ' ';
-		while (--size >= 0) {
+	if (!(spec.flags & LEFT)) {
+		char c = (spec.flags & ZEROPAD) ? '0' : ' ';
+		while (--spec.field_width >= 0) {
 			if (buf < end)
 				*buf = c;
 			++buf;
 		}
 	}
 	/* hmm even more zero padding? */
-	while (i <= --precision) {
+	while (i <= --spec.precision) {
 		if (buf < end)
 			*buf = '0';
 		++buf;
@@ -500,7 +535,7 @@ static char *number(char *buf, char *end
 		++buf;
 	}
 	/* trailing space padding */
-	while (--size >= 0) {
+	while (--spec.field_width >= 0) {
 		if (buf < end)
 			*buf = ' ';
 		++buf;
@@ -508,17 +543,17 @@ static char *number(char *buf, char *end
 	return buf;
 }
 
-static char *string(char *buf, char *end, char *s, int field_width, int precision, int flags)
+static char *string(char *buf, char *end, char *s, struct printf_spec spec)
 {
 	int len, i;
 
 	if ((unsigned long)s < PAGE_SIZE)
 		s = "<NULL>";
 
-	len = strnlen(s, precision);
+	len = strnlen(s, spec.precision);
 
-	if (!(flags & LEFT)) {
-		while (len < field_width--) {
+	if (!(spec.flags & LEFT)) {
+		while (len < spec.field_width--) {
 			if (buf < end)
 				*buf = ' ';
 			++buf;
@@ -529,7 +564,7 @@ static char *string(char *buf, char *end
 			*buf = *s;
 		++buf; ++s;
 	}
-	while (len < field_width--) {
+	while (len < spec.field_width--) {
 		if (buf < end)
 			*buf = ' ';
 		++buf;
@@ -537,21 +572,24 @@ static char *string(char *buf, char *end
 	return buf;
 }
 
-static char *symbol_string(char *buf, char *end, void *ptr, int field_width, int precision, int flags)
+static char *symbol_string(char *buf, char *end, void *ptr,
+				struct printf_spec spec)
 {
 	unsigned long value = (unsigned long) ptr;
 #ifdef CONFIG_KALLSYMS
 	char sym[KSYM_SYMBOL_LEN];
 	sprint_symbol(sym, value);
-	return string(buf, end, sym, field_width, precision, flags);
+	return string(buf, end, sym, spec);
 #else
-	field_width = 2*sizeof(void *);
-	flags |= SPECIAL | SMALL | ZEROPAD;
-	return number(buf, end, value, 16, field_width, precision, flags);
+	spec.field_width = 2*sizeof(void *);
+	spec.flags |= SPECIAL | SMALL | ZEROPAD;
+	spec.base = 16;
+	return number(buf, end, value, spec);
 #endif
 }
 
-static char *resource_string(char *buf, char *end, struct resource *res, int field_width, int precision, int flags)
+static char *resource_string(char *buf, char *end, struct resource *res,
+				struct printf_spec spec)
 {
 #ifndef IO_RSRC_PRINTK_SIZE
 #define IO_RSRC_PRINTK_SIZE	4
@@ -560,7 +598,11 @@ static char *resource_string(char *buf, 
 #ifndef MEM_RSRC_PRINTK_SIZE
 #define MEM_RSRC_PRINTK_SIZE	8
 #endif
-
+	struct printf_spec num_spec = {
+		.base = 16,
+		.precision = -1,
+		.flags = SPECIAL | SMALL | ZEROPAD,
+	};
 	/* room for the actual numbers, the two "0x", -, [, ] and the final zero */
 	char sym[4*sizeof(resource_size_t) + 8];
 	char *p = sym, *pend = sym + sizeof(sym);
@@ -572,13 +614,73 @@ static char *resource_string(char *buf, 
 		size = MEM_RSRC_PRINTK_SIZE;
 
 	*p++ = '[';
-	p = number(p, pend, res->start, 16, size, -1, SPECIAL | SMALL | ZEROPAD);
+	num_spec.field_width = size;
+	p = number(p, pend, res->start, num_spec);
 	*p++ = '-';
-	p = number(p, pend, res->end, 16, size, -1, SPECIAL | SMALL | ZEROPAD);
+	p = number(p, pend, res->end, num_spec);
 	*p++ = ']';
 	*p = 0;
 
-	return string(buf, end, sym, field_width, precision, flags);
+	return string(buf, end, sym, spec);
+}
+
+static char *mac_address_string(char *buf, char *end, u8 *addr,
+				struct printf_spec spec)
+{
+	char mac_addr[6 * 3]; /* (6 * 2 hex digits), 5 colons and trailing zero */
+	char *p = mac_addr;
+	int i;
+
+	for (i = 0; i < 6; i++) {
+		p = pack_hex_byte(p, addr[i]);
+		if (!(spec.flags & SPECIAL) && i != 5)
+			*p++ = ':';
+	}
+	*p = '\0';
+	spec.flags &= ~SPECIAL;
+
+	return string(buf, end, mac_addr, spec);
+}
+
+static char *ip6_addr_string(char *buf, char *end, u8 *addr,
+				struct printf_spec spec)
+{
+	char ip6_addr[8 * 5]; /* (8 * 4 hex digits), 7 colons and trailing zero */
+	char *p = ip6_addr;
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		p = pack_hex_byte(p, addr[2 * i]);
+		p = pack_hex_byte(p, addr[2 * i + 1]);
+		if (!(spec.flags & SPECIAL) && i != 7)
+			*p++ = ':';
+	}
+	*p = '\0';
+	spec.flags &= ~SPECIAL;
+
+	return string(buf, end, ip6_addr, spec);
+}
+
+static char *ip4_addr_string(char *buf, char *end, u8 *addr,
+				struct printf_spec spec)
+{
+	char ip4_addr[4 * 4]; /* (4 * 3 decimal digits), 3 dots and trailing zero */
+	char temp[3];	/* hold each IP quad in reverse order */
+	char *p = ip4_addr;
+	int i, digits;
+
+	for (i = 0; i < 4; i++) {
+		digits = put_dec_trunc(temp, addr[i]) - temp;
+		/* reverse the digits in the quad */
+		while (digits--)
+			*p++ = temp[digits];
+		if (i != 3)
+			*p++ = '.';
+	}
+	*p = '\0';
+	spec.flags &= ~SPECIAL;
+
+	return string(buf, end, ip4_addr, spec);
 }
 
 /*
@@ -592,28 +694,244 @@ static char *resource_string(char *buf, 
  * - 'S' For symbolic direct pointers
  * - 'R' For a struct resource pointer, it prints the range of
  *       addresses (not the name nor the flags)
+ * - 'M' For a 6-byte MAC address, it prints the address in the
+ *       usual colon-separated hex notation
+ * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated
+ *       decimal for v4 and colon separated network-order 16 bit hex for v6)
+ * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is
+ *       currently the same
  *
  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
  * function pointers are really function descriptors, which contain a
  * pointer to the real address.
  */
-static char *pointer(const char *fmt, char *buf, char *end, void *ptr, int field_width, int precision, int flags)
+static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
+			struct printf_spec spec)
 {
+	if (!ptr)
+		return string(buf, end, "(null)", spec);
+
 	switch (*fmt) {
 	case 'F':
 		ptr = dereference_function_descriptor(ptr);
 		/* Fallthrough */
 	case 'S':
-		return symbol_string(buf, end, ptr, field_width, precision, flags);
+		return symbol_string(buf, end, ptr, spec);
 	case 'R':
-		return resource_string(buf, end, ptr, field_width, precision, flags);
+		return resource_string(buf, end, ptr, spec);
+	case 'm':
+		spec.flags |= SPECIAL;
+		/* Fallthrough */
+	case 'M':
+		return mac_address_string(buf, end, ptr, spec);
+	case 'i':
+		spec.flags |= SPECIAL;
+		/* Fallthrough */
+	case 'I':
+		if (fmt[1] == '6')
+			return ip6_addr_string(buf, end, ptr, spec);
+		if (fmt[1] == '4')
+			return ip4_addr_string(buf, end, ptr, spec);
+		spec.flags &= ~SPECIAL;
+		break;
 	}
-	flags |= SMALL;
-	if (field_width == -1) {
-		field_width = 2*sizeof(void *);
-		flags |= ZEROPAD;
+	spec.flags |= SMALL;
+	if (spec.field_width == -1) {
+		spec.field_width = 2*sizeof(void *);
+		spec.flags |= ZEROPAD;
 	}
-	return number(buf, end, (unsigned long) ptr, 16, field_width, precision, flags);
+	spec.base = 16;
+
+	return number(buf, end, (unsigned long) ptr, spec);
+}
+
+/*
+ * Helper function to decode printf style format.
+ * Each call decode a token from the format and return the
+ * number of characters read (or likely the delta where it wants
+ * to go on the next call).
+ * The decoded token is returned through the parameters
+ *
+ * 'h', 'l', or 'L' for integer fields
+ * 'z' support added 23/7/1999 S.H.
+ * 'z' changed to 'Z' --davidm 1/25/99
+ * 't' added for ptrdiff_t
+ *
+ * @fmt: the format string
+ * @type of the token returned
+ * @flags: various flags such as +, -, # tokens..
+ * @field_width: overwritten width
+ * @base: base of the number (octal, hex, ...)
+ * @precision: precision of a number
+ * @qualifier: qualifier of a number (long, size_t, ...)
+ */
+static int format_decode(const char *fmt, struct printf_spec *spec)
+{
+	const char *start = fmt;
+
+	/* we finished early by reading the field width */
+	if (spec->type == FORMAT_TYPE_WIDTH) {
+		if (spec->field_width < 0) {
+			spec->field_width = -spec->field_width;
+			spec->flags |= LEFT;
+		}
+		spec->type = FORMAT_TYPE_NONE;
+		goto precision;
+	}
+
+	/* we finished early by reading the precision */
+	if (spec->type == FORMAT_TYPE_PRECISION) {
+		if (spec->precision < 0)
+			spec->precision = 0;
+
+		spec->type = FORMAT_TYPE_NONE;
+		goto qualifier;
+	}
+
+	/* By default */
+	spec->type = FORMAT_TYPE_NONE;
+
+	for (; *fmt ; ++fmt) {
+		if (*fmt == '%')
+			break;
+	}
+
+	/* Return the current non-format string */
+	if (fmt != start || !*fmt)
+		return fmt - start;
+
+	/* Process flags */
+	spec->flags = 0;
+
+	while (1) { /* this also skips first '%' */
+		bool found = true;
+
+		++fmt;
+
+		switch (*fmt) {
+		case '-': spec->flags |= LEFT;    break;
+		case '+': spec->flags |= PLUS;    break;
+		case ' ': spec->flags |= SPACE;   break;
+		case '#': spec->flags |= SPECIAL; break;
+		case '0': spec->flags |= ZEROPAD; break;
+		default:  found = false;
+		}
+
+		if (!found)
+			break;
+	}
+
+	/* get field width */
+	spec->field_width = -1;
+
+	if (isdigit(*fmt))
+		spec->field_width = skip_atoi(&fmt);
+	else if (*fmt == '*') {
+		/* it's the next argument */
+		spec->type = FORMAT_TYPE_WIDTH;
+		return ++fmt - start;
+	}
+
+precision:
+	/* get the precision */
+	spec->precision = -1;
+	if (*fmt == '.') {
+		++fmt;
+		if (isdigit(*fmt)) {
+			spec->precision = skip_atoi(&fmt);
+			if (spec->precision < 0)
+				spec->precision = 0;
+		} else if (*fmt == '*') {
+			/* it's the next argument */
+			spec->type = FORMAT_TYPE_PRECISION;
+			return ++fmt - start;
+		}
+	}
+
+qualifier:
+	/* get the conversion qualifier */
+	spec->qualifier = -1;
+	if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
+	    *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
+		spec->qualifier = *fmt;
+		++fmt;
+		if (spec->qualifier == 'l' && *fmt == 'l') {
+			spec->qualifier = 'L';
+			++fmt;
+		}
+	}
+
+	/* default base */
+	spec->base = 10;
+	switch (*fmt) {
+	case 'c':
+		spec->type = FORMAT_TYPE_CHAR;
+		return ++fmt - start;
+
+	case 's':
+		spec->type = FORMAT_TYPE_STR;
+		return ++fmt - start;
+
+	case 'p':
+		spec->type = FORMAT_TYPE_PTR;
+		return fmt - start;
+		/* skip alnum */
+
+	case 'n':
+		spec->type = FORMAT_TYPE_NRCHARS;
+		return ++fmt - start;
+
+	case '%':
+		spec->type = FORMAT_TYPE_PERCENT_CHAR;
+		return ++fmt - start;
+
+	/* integer number formats - set up the flags and "break" */
+	case 'o':
+		spec->base = 8;
+		break;
+
+	case 'x':
+		spec->flags |= SMALL;
+
+	case 'X':
+		spec->base = 16;
+		break;
+
+	case 'd':
+	case 'i':
+		spec->flags |= SIGN;
+	case 'u':
+		break;
+
+	default:
+		spec->type = FORMAT_TYPE_INVALID;
+		return fmt - start;
+	}
+
+	if (spec->qualifier == 'L')
+		spec->type = FORMAT_TYPE_LONG_LONG;
+	else if (spec->qualifier == 'l') {
+		if (spec->flags & SIGN)
+			spec->type = FORMAT_TYPE_LONG;
+		else
+			spec->type = FORMAT_TYPE_ULONG;
+	} else if (spec->qualifier == 'Z' || spec->qualifier == 'z') {
+		spec->type = FORMAT_TYPE_SIZE_T;
+	} else if (spec->qualifier == 't') {
+		spec->type = FORMAT_TYPE_PTRDIFF;
+	} else if (spec->qualifier == 'h') {
+		if (spec->flags & SIGN)
+			spec->type = FORMAT_TYPE_SHORT;
+		else
+			spec->type = FORMAT_TYPE_USHORT;
+	} else {
+		if (spec->flags & SIGN)
+			spec->type = FORMAT_TYPE_INT;
+		else
+			spec->type = FORMAT_TYPE_UINT;
+	}
+
+	return ++fmt - start;
 }
 
 /**
@@ -642,18 +960,9 @@ static char *pointer(const char *fmt, ch
 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 {
 	unsigned long long num;
-	int base;
 	char *str, *end, c;
-
-	int flags;		/* flags to number() */
-
-	int field_width;	/* width of output field */
-	int precision;		/* min. # of digits for integers; max
-				   number of chars for from string */
-	int qualifier;		/* 'h', 'l', or 'L' for integer fields */
-				/* 'z' support added 23/7/1999 S.H.    */
-				/* 'z' changed to 'Z' --davidm 1/25/99 */
-				/* 't' added for ptrdiff_t */
+	int read;
+	struct printf_spec spec = {0};
 
 	/* Reject out-of-range values early.  Large positive sizes are
 	   used for unknown buffer sizes. */
@@ -674,184 +983,137 @@ int vsnprintf(char *buf, size_t size, co
 		size = end - buf;
 	}
 
-	for (; *fmt ; ++fmt) {
-		if (*fmt != '%') {
-			if (str < end)
-				*str = *fmt;
-			++str;
-			continue;
-		}
+	while (*fmt) {
+		const char *old_fmt = fmt;
 
-		/* process flags */
-		flags = 0;
-		repeat:
-			++fmt;		/* this also skips first '%' */
-			switch (*fmt) {
-				case '-': flags |= LEFT; goto repeat;
-				case '+': flags |= PLUS; goto repeat;
-				case ' ': flags |= SPACE; goto repeat;
-				case '#': flags |= SPECIAL; goto repeat;
-				case '0': flags |= ZEROPAD; goto repeat;
-			}
+		read = format_decode(fmt, &spec);
 
-		/* get field width */
-		field_width = -1;
-		if (isdigit(*fmt))
-			field_width = skip_atoi(&fmt);
-		else if (*fmt == '*') {
-			++fmt;
-			/* it's the next argument */
-			field_width = va_arg(args, int);
-			if (field_width < 0) {
-				field_width = -field_width;
-				flags |= LEFT;
-			}
-		}
+		fmt += read;
 
-		/* get the precision */
-		precision = -1;
-		if (*fmt == '.') {
-			++fmt;	
-			if (isdigit(*fmt))
-				precision = skip_atoi(&fmt);
-			else if (*fmt == '*') {
-				++fmt;
-				/* it's the next argument */
-				precision = va_arg(args, int);
+		switch (spec.type) {
+		case FORMAT_TYPE_NONE: {
+			int copy = read;
+			if (str < end) {
+				if (copy > end - str)
+					copy = end - str;
+				memcpy(str, old_fmt, copy);
 			}
-			if (precision < 0)
-				precision = 0;
+			str += read;
+			break;
 		}
 
-		/* get the conversion qualifier */
-		qualifier = -1;
-		if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
-		    *fmt =='Z' || *fmt == 'z' || *fmt == 't') {
-			qualifier = *fmt;
-			++fmt;
-			if (qualifier == 'l' && *fmt == 'l') {
-				qualifier = 'L';
-				++fmt;
-			}
-		}
+		case FORMAT_TYPE_WIDTH:
+			spec.field_width = va_arg(args, int);
+			break;
 
-		/* default base */
-		base = 10;
+		case FORMAT_TYPE_PRECISION:
+			spec.precision = va_arg(args, int);
+			break;
 
-		switch (*fmt) {
-			case 'c':
-				if (!(flags & LEFT)) {
-					while (--field_width > 0) {
-						if (str < end)
-							*str = ' ';
-						++str;
-					}
-				}
-				c = (unsigned char) va_arg(args, int);
-				if (str < end)
-					*str = c;
-				++str;
-				while (--field_width > 0) {
+		case FORMAT_TYPE_CHAR:
+			if (!(spec.flags & LEFT)) {
+				while (--spec.field_width > 0) {
 					if (str < end)
 						*str = ' ';
 					++str;
-				}
-				continue;
-
-			case 's':
-				str = string(str, end, va_arg(args, char *), field_width, precision, flags);
-				continue;
-
-			case 'p':
-				str = pointer(fmt+1, str, end,
-						va_arg(args, void *),
-						field_width, precision, flags);
-				/* Skip all alphanumeric pointer suffixes */
-				while (isalnum(fmt[1]))
-					fmt++;
-				continue;
 
-			case 'n':
-				/* FIXME:
-				* What does C99 say about the overflow case here? */
-				if (qualifier == 'l') {
-					long * ip = va_arg(args, long *);
-					*ip = (str - buf);
-				} else if (qualifier == 'Z' || qualifier == 'z') {
-					size_t * ip = va_arg(args, size_t *);
-					*ip = (str - buf);
-				} else {
-					int * ip = va_arg(args, int *);
-					*ip = (str - buf);
 				}
-				continue;
-
-			case '%':
+			}
+			c = (unsigned char) va_arg(args, int);
+			if (str < end)
+				*str = c;
+			++str;
+			while (--spec.field_width > 0) {
 				if (str < end)
-					*str = '%';
+					*str = ' ';
 				++str;
-				continue;
+			}
+			break;
 
-				/* integer number formats - set up the flags and "break" */
-			case 'o':
-				base = 8;
-				break;
+		case FORMAT_TYPE_STR:
+			str = string(str, end, va_arg(args, char *), spec);
+			break;
 
-			case 'x':
-				flags |= SMALL;
-			case 'X':
-				base = 16;
-				break;
+		case FORMAT_TYPE_PTR:
+			str = pointer(fmt+1, str, end, va_arg(args, void *),
+				      spec);
+			while (isalnum(*fmt))
+				fmt++;
+			break;
 
-			case 'd':
-			case 'i':
-				flags |= SIGN;
-			case 'u':
-				break;
+		case FORMAT_TYPE_PERCENT_CHAR:
+			if (str < end)
+				*str = '%';
+			++str;
+			break;
 
-			default:
-				if (str < end)
-					*str = '%';
-				++str;
-				if (*fmt) {
-					if (str < end)
-						*str = *fmt;
-					++str;
-				} else {
-					--fmt;
-				}
-				continue;
+		case FORMAT_TYPE_INVALID:
+			if (str < end)
+				*str = '%';
+			++str;
+			break;
+
+		case FORMAT_TYPE_NRCHARS: {
+			int qualifier = spec.qualifier;
+
+			if (qualifier == 'l') {
+				long *ip = va_arg(args, long *);
+				*ip = (str - buf);
+			} else if (qualifier == 'Z' ||
+					qualifier == 'z') {
+				size_t *ip = va_arg(args, size_t *);
+				*ip = (str - buf);
+			} else {
+				int *ip = va_arg(args, int *);
+				*ip = (str - buf);
+			}
+			break;
 		}
-		if (qualifier == 'L')
-			num = va_arg(args, long long);
-		else if (qualifier == 'l') {
-			num = va_arg(args, unsigned long);
-			if (flags & SIGN)
-				num = (signed long) num;
-		} else if (qualifier == 'Z' || qualifier == 'z') {
-			num = va_arg(args, size_t);
-		} else if (qualifier == 't') {
-			num = va_arg(args, ptrdiff_t);
-		} else if (qualifier == 'h') {
-			num = (unsigned short) va_arg(args, int);
-			if (flags & SIGN)
-				num = (signed short) num;
-		} else {
-			num = va_arg(args, unsigned int);
-			if (flags & SIGN)
-				num = (signed int) num;
+
+		default:
+			switch (spec.type) {
+			case FORMAT_TYPE_LONG_LONG:
+				num = va_arg(args, long long);
+				break;
+			case FORMAT_TYPE_ULONG:
+				num = va_arg(args, unsigned long);
+				break;
+			case FORMAT_TYPE_LONG:
+				num = va_arg(args, long);
+				break;
+			case FORMAT_TYPE_SIZE_T:
+				num = va_arg(args, size_t);
+				break;
+			case FORMAT_TYPE_PTRDIFF:
+				num = va_arg(args, ptrdiff_t);
+				break;
+			case FORMAT_TYPE_USHORT:
+				num = (unsigned short) va_arg(args, int);
+				break;
+			case FORMAT_TYPE_SHORT:
+				num = (short) va_arg(args, int);
+				break;
+			case FORMAT_TYPE_INT:
+				num = (int) va_arg(args, int);
+				break;
+			default:
+				num = va_arg(args, unsigned int);
+			}
+
+			str = number(str, end, num, spec);
 		}
-		str = number(str, end, num, base,
-				field_width, precision, flags);
 	}
+
 	if (size > 0) {
 		if (str < end)
 			*str = '\0';
 		else
 			end[-1] = '\0';
 	}
+
 	/* the trailing null byte doesn't count towards the total */
 	return str-buf;
+
 }
 EXPORT_SYMBOL(vsnprintf);