Mirror/zeek
1
0
Fork 0
mirror of https://github.com/zeek/zeek.git synced 2025-10-07 00:58:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 2

Merge remote-tracking branch 'origin/topic/jsiwek/string-slicing-fix'

Browse source 
* origin/topic/jsiwek/string-slicing-fix:
  Fix string slice notation, addresses BIT-1097.
This commit is contained in:
Robin Sommer 2013-12-04 11:22:31 -08:00
commit 18a23fbdb8
6 changed files with 200 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

38
src/Expr.cc
View file

@ -3037,6 +3037,16 @@ Val* IndexExpr::Eval(Frame* f) const
return result;
}
static int get_slice_index(int idx, int len)
{
if ( abs(idx) > len )
idx = idx > 0 ? len : 0; // Clamp maximum positive/negative indices.
else if ( idx < 0 )
idx += len; // Map to a positive index.
return idx;
}
Val* IndexExpr::Fold(Val* v1, Val* v2) const
{
if ( IsError() )
@ -3058,16 +3068,30 @@ Val* IndexExpr::Fold(Val* v1, Val* v2) const
const ListVal* lv = v2->AsListVal();
const BroString* s = v1->AsString();
int len = s->Len();
bro_int_t first = lv->Index(0)->AsInt();
bro_int_t last = lv->Length() > 1 ? lv->Index(1)->AsInt() : first;
BroString* substring = 0;
if ( first < 0 )
first += len;
if ( lv->Length() == 1 )
{
bro_int_t idx = lv->Index(0)->AsInt();
if ( last < 0 )
last += len;
if ( idx < 0 )
idx += len;
// Out-of-range index will return null pointer.
substring = s->GetSubstring(idx, 1);
}
else
{
bro_int_t first = get_slice_index(lv->Index(0)->AsInt(), len);
bro_int_t last = get_slice_index(lv->Index(1)->AsInt(), len);
int substring_len = last - first;
if ( substring_len < 0 )
substring = 0;
else
substring = s->GetSubstring(first, substring_len);
}
BroString* substring = s->GetSubstring(first, last - first + 1);
return new StringVal(substring ? substring : new BroString(""));
}