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

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
......@@ -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')
cp += 2;
}
while (isxdigit(*cp) &&
(value = isdigit(*cp) ? *cp-'0' : TOLOWER(*cp)-'a'+10) < base) {
result = result*base + value;
if (!base)
base = simple_guess_base(cp);
if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
cp += 2;
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')
cp += 2;
}
while (isxdigit(*cp)
&& (value = isdigit(*cp) ? *cp-'0' : TOLOWER(*cp)-'a'+10) < base) {
result = result*base + value;
if (!base)
base = simple_guess_base(cp);
if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
cp += 2;
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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