@@ -18,6 +18,7 @@ typedef struct pstream {
typedef struct strprops {
char pad;
int npad;
+ bool alternate;
} strprops_t;
static void addchar(pstream_t *p, char c)
@@ -94,7 +95,7 @@ void print_int(pstream_t *ps, long long n, int base, strprops_t props)
void print_unsigned(pstream_t *ps, unsigned long long n, int base,
strprops_t props)
{
- char buf[sizeof(long) * 3 + 1], *p = buf;
+ char buf[sizeof(long) * 3 + 3], *p = buf;
int i;
while (n) {
@@ -104,6 +105,10 @@ void print_unsigned(pstream_t *ps, unsigned long long n, int base,
if (p == buf)
*p++ = '0';
+ else if (props.alternate && base == 16) {
+ *p++ = 'x';
+ *p++ = '0';
+ }
for (i = 0; i < (p - buf) / 2; ++i) {
char tmp;
@@ -225,7 +230,7 @@ int vsnprintf(char *buf, int size, const char *fmt, va_list va)
}
break;
case 'p':
- print_str(&s, "0x", props);
+ props.alternate = true;
print_unsigned(&s, (unsigned long)va_arg(va, void *), 16, props);
break;
case 's':
A simple test: printf(".%8p.\n", (void *)0); printf(".%-8p.\n", (void *)0); printf(".%8p.\n", (void *)1); printf(".%-8p.\n", (void *)1); printf(".%8p.\n", (void *)0x123456); printf(".%-8p.\n", (void *)0x123456); printf(".%2p.\n", (void *)0); printf(".%-2p.\n", (void *)0); printf(".%2p.\n", (void *)1); printf(".%-2p.\n", (void *)1); glibc: . (nil). .(nil) . . 0x1. .0x1 . .0x123456. .0x123456. .(nil). .(nil). .0x1. .0x1. before patch: . 0x 0. .0x 0 . . 0x 1. .0x 1 . . 0x 123456. .0x 123456 . .0x 0. .0x0 . .0x 1. .0x1 . after patch: . 0. .0 . . 0x1. .0x1 . .0x123456. .0x123456. . 0. .0 . .0x1. .0x1. (nil) would be possible with a small change, but the standard leaves it to the implementation and 0 is acceptable, IMO. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> --- lib/printf.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)