@@ -123,6 +123,14 @@ pub fn contains(self: Pack, sha: SHA) ?u32 {
return self.containsPrefix(sha.bin[0..]) catch unreachable;
}
fn orderSha(lhs: []const u8, rhs: []const u8) std.math.Order {
for (lhs, rhs) |l, r| {
if (l > r) return .gt;
if (l < r) return .lt;
}
return .eq;
}
pub fn containsPrefix(self: Pack, par_sha: []const u8) !?u32 {
std.debug.assert(par_sha.len <= 20);
const count: usize = self.fanOutCount(par_sha[0]);
@@ -132,15 +140,43 @@ pub fn containsPrefix(self: Pack, par_sha: []const u8) !?u32 {
const objnames = @as([*][20]u8, @ptrCast(self.objnames[start * 20 ..][0 .. count * 20]))[0..count];
for (0..count) |i| {
const objname = objnames[i];
if (eql(u8, par_sha, objname[0..par_sha.len])) {
if (objnames.len > i + 1 and eql(u8, par_sha, objnames[i + 1][0..par_sha.len])) {
return error.AmbiguousRef;
}
return @byteSwap(self.offsets[i + start]);
var left: usize = 0;
var right: usize = objnames.len;
//var b_idx: usize = 0;
var found: ?usize = null;
while (left < right) {
const mid = left + (right - left) / 2;
switch (orderSha(par_sha, objnames[mid][0..par_sha.len])) {
.eq => {
found = mid;
break;
},
.gt => left = mid + 1,
.lt => right = mid,
}
}
if (found) |f| {
if (objnames.len > f + 1 and eql(u8, par_sha, objnames[f + 1][0..par_sha.len])) {
return error.AmbiguousRef;
}
if (f > 1 and eql(u8, par_sha, objnames[f - 1][0..par_sha.len])) {
return error.AmbiguousRef;
}
return @byteSwap(self.offsets[f + start]);
}
//for (0..count) |i| {
// const objname = objnames[i];
// if (eql(u8, par_sha, objname[0..par_sha.len])) {
// if (objnames.len > i + 1 and eql(u8, par_sha, objnames[i + 1][0..par_sha.len])) {
// return error.AmbiguousRef;
// }
// return @byteSwap(self.offsets[i + start]);
// }
//}
return null;
}