On Wed, 2016-02-03 at 22:14 +0100, Jason A. Donenfeld wrote:
> The idea here is to be able to printk a sockaddr_in6, and have it show
> something that looks like what the user would naturally pass to
> getaddrinfo(3), which is entirely complete.
>
> However, I could be convinced that this kind of behavior belongs in
> it's own flag. Maybe I'll cook up a flag for that instead.
I think that'd be best.
Maybe using something like %pISG for this that
would optionally show these flow and scope values
only when non-zero.
Something like:
---
lib/vsprintf.c | 30 +++++++++++++++++++-----------
1 file changed, 19 insertions(+), 11 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 6dc4288..2003c6f 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1147,7 +1147,8 @@ static noinline_for_stack
char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
struct printf_spec spec, const char *fmt)
{
- bool have_p = false, have_s = false, have_f = false, have_c = false;
+ u8 show_p = 0, show_s = 0, show_f = 0;
+ bool use_c = false;
char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]")
+
sizeof(":12345") + sizeof("/123456789") +
sizeof("%1234567890")];
@@ -1160,43 +1161,50 @@ char *ip6_addr_string_sa(char *buf, char *end, const
struct sockaddr_in6 *sa,
while (isalpha(*++fmt)) {
switch (*fmt) {
case 'p':
- have_p = true;
+ show_p = 1;
break;
case 'f':
- have_f = true;
+ show_f = 1;
break;
case 's':
- have_s = true;
+ show_s = 1;
+ break;
+ case 'G':
+ show_p = 2;
+ show_f = 2;
+ show_s = 2;
break;
case 'c':
- have_c = true;
+ use_c = true;
break;
}
}
- if (have_p || have_s || have_f) {
+ if (show_p || show_s || show_f) {
*p = '[';
off = 1;
}
- if (fmt6[0] == 'I' && have_c)
+ if (fmt6[0] == 'I' && use_c)
p = ip6_compressed_string(ip6_addr + off, addr);
else
p = ip6_string(ip6_addr + off, addr, fmt6);
- if (have_p || have_s || have_f)
+ if (show_p || show_s || show_f)
*p++ = ']';
- if (have_p) {
+ if (show_p) {
*p++ = ':';
p = number(p, pend, ntohs(sa->sin6_port), spec);
}
- if (have_f) {
+ if (show_f == 1 ||
+ (show_f == 2 && (sa->sin6_flowinfo & IPV6_FLOWINFO_MASK))) {
*p++ = '/';
p = number(p, pend, ntohl(sa->sin6_flowinfo &
IPV6_FLOWINFO_MASK), spec);
}
- if (have_s) {
+ if (show_s == 1 ||
+ (show_s == 2 && sa->sin6_scope_id)) {
*p++ = '%';
p = number(p, pend, sa->sin6_scope_id, spec);
}
