From 325178506187df037f9a85eb2e09100eb794f4f9 Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Sat, 22 Jul 2023 23:27:02 -0600 Subject: Pull the json-hex-encoding from shortsum to jsonutil --- lib/jsonutil/hex_string.go | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100644 lib/jsonutil/hex_string.go (limited to 'lib/jsonutil/hex_string.go') diff --git a/lib/jsonutil/hex_string.go b/lib/jsonutil/hex_string.go new file mode 100644 index 0000000..06970ce --- /dev/null +++ b/lib/jsonutil/hex_string.go @@ -0,0 +1,42 @@ +// Copyright (C) 2023 Luke Shumaker +// +// SPDX-License-Identifier: GPL-2.0-or-later + +// Package jsonutil provides utilities for implementing the interfaces +// consumed by the "git.lukeshu.com/go/lowmemjson" package. +package jsonutil + +import ( + "io" + + "git.lukeshu.com/go/lowmemjson" +) + +func EncodeHexString[T ~[]byte | ~string](w io.Writer, str T) error { + const hextable = "0123456789abcdef" + var buf [2]byte + buf[0] = '"' + if _, err := w.Write(buf[:1]); err != nil { + return err + } + for i := 0; i < len(str); i++ { + buf[0] = hextable[str[i]>>4] + buf[1] = hextable[str[i]&0x0f] + if _, err := w.Write(buf[:]); err != nil { + return err + } + } + buf[0] = '"' + if _, err := w.Write(buf[:1]); err != nil { + return err + } + return nil +} + +func DecodeHexString(r io.RuneScanner, dst io.ByteWriter) error { + dec := &hexDecoder{dst: dst} + if err := lowmemjson.DecodeString(r, dec); err != nil { + return err + } + return dec.Close() +} -- cgit v1.2.3-2-g168b From c65d6effc26c3d97a6193f65c5b7698c830d9ff0 Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Fri, 6 Jan 2023 00:52:43 -0700 Subject: btrfssum: Don't emit JSON strings that are too long Split it, and wrap it in an array. --- lib/jsonutil/hex_string.go | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'lib/jsonutil/hex_string.go') diff --git a/lib/jsonutil/hex_string.go b/lib/jsonutil/hex_string.go index 06970ce..3e0b154 100644 --- a/lib/jsonutil/hex_string.go +++ b/lib/jsonutil/hex_string.go @@ -40,3 +40,47 @@ func DecodeHexString(r io.RuneScanner, dst io.ByteWriter) error { } return dec.Close() } + +func EncodeSplitHexString[T ~[]byte | ~string](w io.Writer, str T, maxStrLen int) error { + if maxStrLen <= 0 || len(str) <= maxStrLen/2 { + return EncodeHexString(w, str) + } + var buf [1]byte + buf[0] = '[' + if _, err := w.Write(buf[:]); err != nil { + return err + } + for len(str) > maxStrLen/2 { + if err := EncodeHexString(w, str[:maxStrLen/2]); err != nil { + return err + } + str = str[maxStrLen/2:] + if len(str) > 0 { + buf[0] = ',' + if _, err := w.Write(buf[:]); err != nil { + return err + } + } + } + if len(str) > 0 { + if err := EncodeHexString(w, str); err != nil { + return err + } + } + buf[0] = ']' + if _, err := w.Write(buf[:]); err != nil { + return err + } + return nil +} + +func DecodeSplitHexString(r io.RuneScanner, dst io.ByteWriter) error { + c, _, _ := r.ReadRune() + _ = r.UnreadRune() + if c == '"' { + return DecodeHexString(r, dst) + } + return lowmemjson.DecodeArray(r, func(r io.RuneScanner) error { + return DecodeHexString(r, dst) + }) +} -- cgit v1.2.3-2-g168b