###Bug in mask###
Bug in mask
Your function doesn't actually do the right thing because of this line:
unsigned int mask = 1 << (sizeof (n) - 1);
On a 32-bit system, you wanted mask to be 1 << 31 but what you actually got was 1 << 3 because sizeof(unsigned int) is 4. The correct way would be:
unsigned int mask = 1 << (sizeof(n) * CHAR_BIT - 1);
because sizeof returns a number of bytes and CHAR_BIT is defined to be the number of bits per byte.
Of course, if you used the loop Peter Taylor suggested, you wouldn't even need mask.
###Bug in mask###
Your function doesn't actually do the right thing because of this line:
unsigned int mask = 1 << (sizeof (n) - 1);
On a 32-bit system, you wanted mask to be 1 << 31 but what you actually got was 1 << 3 because sizeof(unsigned int) is 4. The correct way would be:
unsigned int mask = 1 << (sizeof(n) * CHAR_BIT - 1);
because sizeof returns a number of bytes and CHAR_BIT is defined to be the number of bits per byte.
Of course, if you used the loop Peter Taylor suggested, you wouldn't even need mask.
Bug in mask
Your function doesn't actually do the right thing because of this line:
unsigned int mask = 1 << (sizeof (n) - 1);
On a 32-bit system, you wanted mask to be 1 << 31 but what you actually got was 1 << 3 because sizeof(unsigned int) is 4. The correct way would be:
unsigned int mask = 1 << (sizeof(n) * CHAR_BIT - 1);
because sizeof returns a number of bytes and CHAR_BIT is defined to be the number of bits per byte.
Of course, if you used the loop Peter Taylor suggested, you wouldn't even need mask.
###Bug in mask###
Your function doesn't actually do the right thing because of this line:
unsigned int mask = 1 << (sizeof (n) - 1);
On a 32-bit system, you wanted mask to be 1 << 31 but what you actually got was 1 << 3 because sizeof(unsigned int) is 4. The correct way would be:
unsigned int mask = 1 << (sizeof(n) * CHAR_BIT - 1);
because sizeof returns a number of bytes and CHAR_BIT is defined to be the number of bits per byte.
Of course, if you used the loop Peter Taylor suggested, you wouldn't even need mask.