zzstoatzz.io
atproto relay implementation in zig
zlay.waow.tech
fix: URL-decode query parameters (cursor, did)
clients may percent-encode colons in DIDs (did%3Aplc%3A...), which
broke cursor-based pagination — the encoded cursor didn't match any
RocksDB key so the scan restarted from the beginning.
adds queryParamDecoded() with a hexVal helper for percent-decoding
into a caller-provided buffer. applied to cursor in
listReposByCollection and did in getRepoStatus/getLatestCommit.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
+56
-3
src/main.zig
+56
-3
src/main.zig
···
591
591
}
592
592
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593
fn handleGetRepoStatus(stream: std.net.Stream, query: []const u8, persist: *event_log_mod.DiskPersist) void {
594
-
const did = queryParam(query, "did") orelse {
594
+
var did_buf: [256]u8 = undefined;
595
+
const did = queryParamDecoded(query, "did", &did_buf) orelse {
595
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httpRespondJson(stream, "400 Bad Request", "{\"error\":\"BadRequest\",\"message\":\"did parameter required\"}");
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597
return;
597
598
};
···
651
652
}
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fn handleGetLatestCommit(stream: std.net.Stream, query: []const u8, persist: *event_log_mod.DiskPersist) void {
654
-
const did = queryParam(query, "did") orelse {
655
+
var did_buf: [256]u8 = undefined;
656
+
const did = queryParamDecoded(query, "did", &did_buf) orelse {
655
657
httpRespondJson(stream, "400 Bad Request", "{\"error\":\"BadRequest\",\"message\":\"did parameter required\"}");
656
658
return;
657
659
};
···
736
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return;
737
739
}
738
740
739
-
const cursor_did = queryParam(query, "cursor");
741
+
var cursor_buf: [256]u8 = undefined;
742
+
const cursor_did = queryParamDecoded(query, "cursor", &cursor_buf);
740
743
741
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// scan collection index
742
745
var did_buf: [65536]u8 = undefined;
···
783
786
}
784
787
}
785
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return null;
789
+
}
790
+
791
+
/// like queryParam but percent-decodes the value into buf.
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+
/// returns null if the param is missing, or a slice into buf with the decoded value.
793
+
fn queryParamDecoded(query: []const u8, name: []const u8, buf: []u8) ?[]const u8 {
794
+
const raw = queryParam(query, name) orelse return null;
795
+
var i: usize = 0;
796
+
var out: usize = 0;
797
+
while (i < raw.len) {
798
+
if (raw[i] == '%' and i + 2 < raw.len) {
799
+
const hi = hexVal(raw[i + 1]) orelse {
800
+
if (out >= buf.len) return null;
801
+
buf[out] = raw[i];
802
+
out += 1;
803
+
i += 1;
804
+
continue;
805
+
};
806
+
const lo = hexVal(raw[i + 2]) orelse {
807
+
if (out >= buf.len) return null;
808
+
buf[out] = raw[i];
809
+
out += 1;
810
+
i += 1;
811
+
continue;
812
+
};
813
+
if (out >= buf.len) return null;
814
+
buf[out] = (hi << 4) | lo;
815
+
out += 1;
816
+
i += 3;
817
+
} else if (raw[i] == '+') {
818
+
if (out >= buf.len) return null;
819
+
buf[out] = ' ';
820
+
out += 1;
821
+
i += 1;
822
+
} else {
823
+
if (out >= buf.len) return null;
824
+
buf[out] = raw[i];
825
+
out += 1;
826
+
i += 1;
827
+
}
828
+
}
829
+
return buf[0..out];
830
+
}
831
+
832
+
fn hexVal(c: u8) ?u4 {
833
+
return switch (c) {
834
+
'0'...'9' => @intCast(c - '0'),
835
+
'a'...'f' => @intCast(c - 'a' + 10),
836
+
'A'...'F' => @intCast(c - 'A' + 10),
837
+
else => null,
838
+
};
786
839
}
787
840
788
841
fn httpRespondJson(stream: std.net.Stream, status: []const u8, body: []const u8) void {