[iproute PATCH v4 3/6] lib/inet_proto: Review inet_proto_{a2n,n2a}()
flat view
STALE3346d
From: Phil Sutter <phil@nwl.cc>
Date: 2017-08-24 09:52:28
Subsystem:
library code, the rest · Maintainers:
Andrew Morton, Linus Torvalds
Revision v4 of 3 in this series.
Revisions (3)
- v2 [diff vs current]
- v3 [diff vs current]
- v4 current
The original intent was to make sure strings written by those functions are NUL-terminated at all times, though it was suggested to get rid of the 15 char protocol name limit as well which this patch accomplishes. In addition to that, simplify inet_proto_a2n() a bit: Use the error checking in get_u8() to find out whether passed 'buf' contains a valid decimal number instead of checking the first character's value manually. Signed-off-by: Phil Sutter <phil@nwl.cc> --- lib/inet_proto.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/lib/inet_proto.c b/lib/inet_proto.c
index ceda082b12a2e..53c029039b6d5 100644
--- a/lib/inet_proto.c
+++ b/lib/inet_proto.c@@ -25,7 +25,7 @@ const char *inet_proto_n2a(int proto, char *buf, int len) { - static char ncache[16]; + static char *ncache; static int icache = -1; struct protoent *pe;
@@ -34,9 +34,12 @@ const char *inet_proto_n2a(int proto, char *buf, int len) pe = getprotobynumber(proto); if (pe) { + if (icache != -1) + free(ncache); icache = proto; - strncpy(ncache, pe->p_name, 16); - strncpy(buf, pe->p_name, len); + ncache = strdup(pe->p_name); + strncpy(buf, pe->p_name, len - 1); + buf[len - 1] = '\0'; return buf; } snprintf(buf, len, "ipproto-%d", proto);
@@ -45,24 +48,23 @@ const char *inet_proto_n2a(int proto, char *buf, int len) int inet_proto_a2n(const char *buf) { - static char ncache[16]; + static char *ncache; static int icache = -1; struct protoent *pe; + __u8 ret; - if (icache>=0 && strcmp(ncache, buf) == 0) + if (icache != -1 && strcmp(ncache, buf) == 0) return icache; - if (buf[0] >= '0' && buf[0] <= '9') { - __u8 ret; - if (get_u8(&ret, buf, 10)) - return -1; + if (!get_u8(&ret, buf, 10)) return ret; - } pe = getprotobyname(buf); if (pe) { + if (icache != -1) + free(ncache); icache = pe->p_proto; - strncpy(ncache, pe->p_name, 16); + ncache = strdup(pe->p_name); return pe->p_proto; } return -1;
--
2.13.1