diff options
| author | João Valverde <j@v6e.pt> | 2022-02-27 09:56:41 +0000 |
|---|---|---|
| committer | A Wireshark GitLab Utility <gerald+gitlab-utility@wireshark.org> | 2022-03-28 11:20:41 +0000 |
| commit | ac0a69636ba799f976c7fc01f137c0bbb89b0a17 (patch) | |
| tree | 67eacf57e0a627ed8da5053207e9d4ad0927414e /epan/ftypes/ftype-ipv4.c | |
| parent | 677b68aa3b58558d9062f2c80ef72cfc2ec0c4d8 (diff) | |
dfilter: Add support for unary arithmetic
This change implements a unary minus operator.
Filter: tcp.window_size_scalefactor == -tcp.dstport
Instructions:
00000 READ_TREE tcp.window_size_scalefactor -> reg#0
00001 IF_FALSE_GOTO 6
00002 READ_TREE tcp.dstport -> reg#1
00003 IF_FALSE_GOTO 6
00004 MK_MINUS -reg#1 -> reg#2
00005 ANY_EQ reg#0 == reg#2
00006 RETURN
It is supported for integer types, floats and relative time values.
The unsigned integer types are promoted to a 32 bit signed integer.
Unary plus is implemented as a no-op. The plus sign is simply ignored.
Constant arithmetic expressions are computed during compilation.
Overflow with constants is a compile time error. Overflow with
variables is a run time error and silently ignored. Only a debug
message will be printed to the console.
Related to #15504.
Diffstat (limited to 'epan/ftypes/ftype-ipv4.c')
| -rw-r--r-- | epan/ftypes/ftype-ipv4.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/epan/ftypes/ftype-ipv4.c b/epan/ftypes/ftype-ipv4.c index d3cf02a947..fe032cf7f4 100644 --- a/epan/ftypes/ftype-ipv4.c +++ b/epan/ftypes/ftype-ipv4.c @@ -172,6 +172,7 @@ ftype_register_ipv4(void) NULL, slice, bitwise_and, + NULL, /* unary_minus */ }; ftype_register(FT_IPv4, &ipv4_type); |