Commit aa46a63e authored by Harvey Harrison's avatar Harvey Harrison Committed by Linus Torvalds
Browse files

lib: pull base-guessing logic to helper function 



The default base is 10 unless there is a leading zero, in which
case the base will be guessed as 8.

The base will only be guesed as 16 when the string starts with '0x'
the third character is a valid hex digit.

Signed-off-by: default avatarHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 73b4a24f

lib/vsprintf.c

+42 −38
Original line number Diff line number Diff line
@@ -32,6 +32,18 @@ 
/* Works only for digits and letters, but small and fast */

#define TOLOWER(x) ((x) | 0x20)



static unsigned int simple_guess_base(const char *cp)

{

	if (cp[0] == '0') {

		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))

			return 16;

		else

			return 8;

	} else {

		return 10;

	}

}



/**

 * simple_strtoul - convert a string to an unsigned long

 * @cp: The start of the string
@@ -40,32 +52,28 @@ 
 */

unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base)

{

	unsigned long result = 0,value;

	unsigned long result = 0;



	if (!base) {

		base = 10;

		if (*cp == '0') {

			base = 8;

			cp++;

			if ((TOLOWER(*cp) == 'x') && isxdigit(cp[1])) {

				cp++;

				base = 16;

			}

		}

	} else if (base == 16) {

		if (cp[0] == '0' && TOLOWER(cp[1]) == 'x')

	if (!base)

		base = simple_guess_base(cp);



	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')

		cp += 2;

	}

	while (isxdigit(*cp) &&

	       (value = isdigit(*cp) ? *cp-'0' : TOLOWER(*cp)-'a'+10) < base) {



	while (isxdigit(*cp)) {

		unsigned int value;



		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;

		if (value >= base)

			break;

		result = result * base + value;

		cp++;

	}



	if (endp)

		*endp = (char *)cp;

	return result;

}



EXPORT_SYMBOL(simple_strtoul);



/**
@@ -91,32 +99,28 @@ EXPORT_SYMBOL(simple_strtol); 
 */

unsigned long long simple_strtoull(const char *cp,char **endp,unsigned int base)

{

	unsigned long long result = 0,value;

	unsigned long long result = 0;



	if (!base) {

		base = 10;

		if (*cp == '0') {

			base = 8;

			cp++;

			if ((TOLOWER(*cp) == 'x') && isxdigit(cp[1])) {

				cp++;

				base = 16;

			}

		}

	} else if (base == 16) {

		if (cp[0] == '0' && TOLOWER(cp[1]) == 'x')

	if (!base)

		base = simple_guess_base(cp);



	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')

		cp += 2;

	}

	while (isxdigit(*cp)

	 && (value = isdigit(*cp) ? *cp-'0' : TOLOWER(*cp)-'a'+10) < base) {



	while (isxdigit(*cp)) {

		unsigned int value;



		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;

		if (value >= base)

			break;

		result = result * base + value;

		cp++;

	}



	if (endp)

		*endp = (char *)cp;

	return result;

}



EXPORT_SYMBOL(simple_strtoull);



/**

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