mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2025-12-16 03:03:09 +00:00
Code Issues Packages Projects Releases Wiki Activity

linux.bpf: expose map_get_next_key

Browse Source 
Returning a bool allows to conveniently use it as the condition
of a while loop.

Also remove restriction that ST cannot be double-word.
While imm is only 32-bit, this value is extended into a 64-bit
memory location.
This commit is contained in:
bfredl 2022-11-24 09:52:09 +01:00 committed by Andrew Kelley
parent 87a14f2b03
commit 0196010b0c
1 changed files with 31 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
lib/std/os/linux/bpf.zig
View File

@ -667,7 +667,6 @@ pub const Insn = packed struct {
}
pub fn st(comptime size: Size, dst: Reg, off: i16, imm: i32) Insn {
if (size == .double_word) @compileError("TODO: need to determine how to correctly handle double words");
return Insn{
.code = MEM | @enumToInt(size) | ST,
.dst = @enumToInt(dst),
@ -1585,6 +1584,27 @@ pub fn map_delete_elem(fd: fd_t, key: []const u8) !void {
}
}
pub fn map_get_next_key(fd: fd_t, key: []const u8, next_key: []u8) !bool {
var attr = Attr{
.map_elem = std.mem.zeroes(MapElemAttr),
};
attr.map_elem.map_fd = fd;
attr.map_elem.key = @ptrToInt(key.ptr);
attr.map_elem.result.next_key = @ptrToInt(next_key.ptr);
const rc = linux.bpf(.map_get_next_key, &attr, @sizeOf(MapElemAttr));
switch (errno(rc)) {
.SUCCESS => return true,
.BADF => return error.BadFd,
.FAULT => unreachable,
.INVAL => return error.FieldInAttrNeedsZeroing,
.NOENT => return false,
.PERM => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
test "map lookup, update, and delete" {
const key_size = 4;
const value_size = 4;
@ -1605,6 +1625,16 @@ test "map lookup, update, and delete" {
const second_key = [key_size]u8{ 0, 0, 0, 1 };
try expectError(error.ReachedMaxEntries, map_update_elem(map, &second_key, &value, 0));
// succeed at iterating all keys of map
var lookup_key = [_]u8{ 1, 0, 0, 0 };
var next_key = [_]u8{ 2, 3, 4, 5 }; // garbage value
const status = try map_get_next_key(map, &lookup_key, &next_key);
try expectEqual(status, true);
try expectEqual(next_key, key);
std.mem.copy(u8, &lookup_key, &next_key);
const status2 = try map_get_next_key(map, &lookup_key, &next_key);
try expectEqual(status2, false);
// succeed at deleting an existing elem
try map_delete_elem(map, &key);
try expectError(error.NotFound, map_lookup_elem(map, &key, &value));