Versioned key-value state serialization for processor presets. More...
#include <algorithm>#include <cassert>#include <cmath>#include <cstdint>#include <cstdio>#include <cstring>#include <string>#include <vector>
Go to the source code of this file.
Classes | |
| class | dspark::StateWriter |
| Serializes key/value parameters into a versioned blob. More... | |
| class | dspark::StateReader |
| Tolerant reader: missing keys yield defaults, unknown keys are skipped. More... | |
| struct | dspark::StateReader::Entry |
| Access for generic tooling (JSON rendering, preset browsers). More... | |
Namespaces | |
| namespace | dspark |
| Main namespace for the DSPark framework. | |
| namespace | dspark::detail |
Functions | |
| void | dspark::detail::appendStateJsonString (std::string &out, const std::string &s) |
| Appends a JSON string literal, escaping the characters JSON forbids. Keys follow the [A-Za-z0-9._] convention (so this normally emits verbatim), but the convention is not enforced on the writer or reader, and untrusted blobs can carry arbitrary key bytes; escaping keeps the emitted JSON valid and non-injectable in every case. | |
| void | dspark::detail::appendStateJsonNumber (std::string &out, float v) |
| Locale-independent float rendering ("%.9g" with a forced dot). Non-finite payloads (NaN/Inf – e.g. a corrupt blob or a bugged parameter) are emitted as JSON-legal 0 so the output always parses and round-trips. | |
| const char * | dspark::detail::parseStateJsonNumber (const char *s, const char *end, double &out) noexcept |
| Locale-independent number parse over [s, end); nullptr on failure. | |
| std::string | dspark::detail::stateToJsonImpl (const std::vector< uint8_t > &blob, int depth) |
| std::vector< uint8_t > | dspark::detail::stateFromJsonImpl (const std::string &json, int depth) |
| std::string | dspark::stateToJson (const std::vector< uint8_t > &blob) |
| Renders a state blob as a flat JSON object string. | |
| std::vector< uint8_t > | dspark::stateFromJson (const std::string &json) |
| Parses the JSON produced by stateToJson() back into a blob. | |
| constexpr uint32_t | dspark::stateId (const char(&tag)[5]) noexcept |
| Builds a FOURCC processor id, e.g. dspark::stateId("COMP"). | |
Variables | |
| constexpr int | dspark::detail::kMaxStateJsonDepth = 32 |
Detailed Description
Versioned key-value state serialization for processor presets.
The uniform getState()/setState() backbone: processors serialize their parameters as readable key/value entries into a compact, versioned binary blob, and restore tolerantly – unknown keys are ignored, missing keys keep their defaults, so presets survive both directions of version drift.
Layout (little-endian):
"DSPK" | format u16 | processorId u32 | processorVersion u16 | count u16 count x ( keyLen u8 | key bytes | type u8 | payload 4 bytes )
Types: 0 = float, 1 = int32, 2 = bool. Keys are short ASCII strings (letters, digits, '.', '_' – no quotes or backslashes, so the JSON helpers never need escaping), which keeps blobs self-describing: stateToJson() renders any blob as a flat JSON object and stateFromJson() parses that same subset back – no external libraries. Both are locale-independent: a host process running with a decimal-comma LC_NUMERIC (the classic plugin bug) cannot corrupt the number formatting or parsing.
Serialization is a setup/UI-thread operation (it allocates); never call it from the audio callback. That matches every plugin host's preset flow.
Dependencies: C++20 standard library only.
Definition in file StateBlob.h.
