extension_registry.h File Reference

Extension Registry – manages grammar extensions with rich metadata. More...

#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>

Go to the source code of this file.

Data Structures
struct	ExtensionOrder
	Result of dependency resolution: a sorted array of extension names in load order (dependencies before dependents). More...
struct	GrammarExtensionMetadata
	Metadata describing a grammar extension participant in the execution pipeline. More...
struct	OracleContext
	Context passed to an oracle callback when the system needs a disambiguation decision. More...

Typedefs
typedef struct ExtensionRegistry	ExtensionRegistry
	Opaque extension registry handle.
typedef bool(*	ExtensionVisitorFn) (const GrammarExtensionMetadata *meta, void *user_data)
	Visitor callback for extension iteration.
typedef int(*	OracleCallback) (const OracleContext *ctx)
	Oracle callback type.

Enumerations
enum	DisambiguationStrategy {   DISAMBIG_PRIORITY = 0 , DISAMBIG_FORK_RESOLVE , DISAMBIG_ORACLE , DISAMBIG_CONTEXT ,   DISAMBIG_NONE }
	How an extension prefers to resolve ambiguities introduced by its grammar modifications. More...
enum	ExecutionPolicy { EXEC_SEQUENTIAL = 0 , EXEC_PARALLEL , EXEC_PIPELINE , EXEC_LAZY }
	Controls how an extension's modifications are applied relative to other extensions. More...

Functions
void	extension_order_destroy (ExtensionOrder *order)
	Free an ExtensionOrder and all owned strings.
bool	extension_registry_check_dependencies (ExtensionRegistry *reg, char **error_out)
	Validate all dependency and conflict declarations.
uint32_t	extension_registry_count (const ExtensionRegistry *reg)
	Return the number of registered extensions.
ExtensionRegistry *	extension_registry_create (void)
	Create an empty extension registry.
void	extension_registry_destroy (ExtensionRegistry *reg)
	Destroy the registry and free all owned memory.
const GrammarExtensionMetadata *	extension_registry_find (ExtensionRegistry *reg, const char *name)
	Look up an extension by name.
void	extension_registry_foreach (const ExtensionRegistry *reg, ExtensionVisitorFn visitor, void *user_data)
	Iterate over all registered extensions.
bool	extension_registry_get_order (ExtensionRegistry *reg, ExtensionOrder *order_out, char **error_out)
	Produce a topological ordering of all registered extensions.
bool	extension_registry_register (ExtensionRegistry *reg, const GrammarExtensionMetadata *metadata)
	Register an extension with its metadata.
bool	extension_registry_unregister (ExtensionRegistry *reg, const char *name)
	Unregister an extension by name.

Detailed Description

Extension Registry – manages grammar extensions with rich metadata.

The extension registry manages grammar extensions with metadata including disambiguation strategies, execution policies, dependency tracking, and conflict declarations. It builds on the existing extension system (src/extension.h) by adding:

• Per-extension disambiguation strategy and priority
• Execution policy (sequential, parallel, pipeline, etc.)
• Oracle callbacks for runtime conflict resolution
• Declarative dependency and conflict relationships
• Topological ordering with cycle detection
• Hash-table-backed O(1) lookups by name

Usage Example

ExtensionRegistry *reg = extension_registry_create();
 
GrammarExtensionMetadata meta = {
    .name    = "jsonb",
    .version = "1.0.0",
    .strategy = DISAMBIG_PRIORITY,
    .priority = 100,
    .policy   = EXEC_SEQUENTIAL,
};
extension_registry_register(reg, &meta);
 
char *error = NULL;
extension_registry_check_dependencies(reg, &error);
 
extension_registry_destroy(reg);

See also

disambiguation.h for conflict resolution strategies.

execution_policy.h for execution policy details.

Definition in file extension_registry.h.