le_json.h File Reference

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Typedefs
typedef void(*	le_json_EventHandler_t) (le_json_Event_t event)
typedef void(*	le_json_ErrorHandler_t) (le_json_Error_t error, const char *msg)
typedef struct le_json_ParsingSession *	le_json_ParsingSessionRef_t

Enumerations
enum	le_json_Event_t {   LE_JSON_OBJECT_START, LE_JSON_OBJECT_MEMBER, LE_JSON_OBJECT_END, LE_JSON_ARRAY_START,   LE_JSON_ARRAY_END, LE_JSON_STRING, LE_JSON_NUMBER, LE_JSON_TRUE,   LE_JSON_FALSE, LE_JSON_NULL, LE_JSON_DOC_END }
enum	le_json_Error_t { LE_JSON_SYNTAX_ERROR, LE_JSON_READ_ERROR }
enum	le_json_ContextType_t {   LE_JSON_CONTEXT_DOC, LE_JSON_CONTEXT_OBJECT, LE_JSON_CONTEXT_MEMBER, LE_JSON_CONTEXT_ARRAY,   LE_JSON_CONTEXT_STRING, LE_JSON_CONTEXT_NUMBER, LE_JSON_CONTEXT_TRUE, LE_JSON_CONTEXT_FALSE,   LE_JSON_CONTEXT_NULL }

Functions
le_json_ParsingSessionRef_t	le_json_Parse (int fd, le_json_EventHandler_t eventHandler, le_json_ErrorHandler_t errorHandler, void *opaquePtr)
void	le_json_Cleanup (le_json_ParsingSessionRef_t session)
void	le_json_SetEventHandler (le_json_EventHandler_t callbackFunc)
le_json_ContextType_t	le_json_GetContextType (void)
void	le_json_SetOpaquePtr (void *ptr)
void *	le_json_GetOpaquePtr (void)
void	le_json_SetErrorHandler (le_json_ErrorHandler_t callbackFunc)
const char *	le_json_GetString (void)
double	le_json_GetNumber (void)
const char *	le_json_GetEventName (le_json_Event_t event)
const char *	le_json_GetContextName (le_json_ContextType_t context)
size_t	le_json_GetBytesRead (le_json_ParsingSessionRef_t session)
le_json_ParsingSessionRef_t	le_json_GetSession (void)

Detailed Description

Legato JSON Parsing API include file.

Copyright (C) Sierra Wireless Inc. Use of this work is subject to license.

Typedef Documentation

typedef void(* le_json_ErrorHandler_t) (le_json_Error_t error, const char *msg)

Callbacks for errors look like this.

Parameters

error	[in] Indicates what type of error occured.
msg	[in] Human-readable message describing the error. (Valid until handler returns.)

typedef void(* le_json_EventHandler_t) (le_json_Event_t event)

Callbacks for (non-error) parsing events look like this.

Parameters

event

[in] Indicates what type of event occured.

typedef struct le_json_ParsingSession* le_json_ParsingSessionRef_t

Parsing session reference. Refers to a parsing session started by le_json_Parse(). Pass this to le_json_Cleanup() to stop the parsing and clean up memory allocated by the parser.

Enumeration Type Documentation

enum le_json_ContextType_t

Enumeration of the different types of "contexts" that can exist during a parsing session.

Enumerator
LE_JSON_CONTEXT_DOC	Top level of document, outside the main object/array.
LE_JSON_CONTEXT_OBJECT	Parsing an object (set of named members).
LE_JSON_CONTEXT_MEMBER	Parsing a member of an object.
LE_JSON_CONTEXT_ARRAY	Parsing an array (list of unnamed elements).
LE_JSON_CONTEXT_STRING	Parsing a string value.
LE_JSON_CONTEXT_NUMBER	Parsing number value.
LE_JSON_CONTEXT_TRUE	Parsing a true value.
LE_JSON_CONTEXT_FALSE	Parsing a false value.
LE_JSON_CONTEXT_NULL	Parsing a null value.

enum le_json_Error_t

Enumeration of the different types of errors that can be reported during JSON document parsing.

Enumerator
LE_JSON_SYNTAX_ERROR	Syntax error, such as a missing comma or extra comma.
LE_JSON_READ_ERROR	Error when reading from the input byte stream.

enum le_json_Event_t

Enumeration of all the different events that can be reported during JSON document parsing.

Enumerator
LE_JSON_OBJECT_START	object started, subsequent object members are part of this object
LE_JSON_OBJECT_MEMBER	object member name received: Call le_json_GetString() to get name
LE_JSON_OBJECT_END	object finished, subsequent members/values are outside this object
LE_JSON_ARRAY_START	array started, upcoming values are elements of this array
LE_JSON_ARRAY_END	array finished, subsequent values are outside this array
LE_JSON_STRING	string value received: call le_json_GetString() to get value
LE_JSON_NUMBER	number value received: call le_json_GetNumber() to get value
LE_JSON_TRUE	true value received
LE_JSON_FALSE	false value received
LE_JSON_NULL	null value received
LE_JSON_DOC_END	End of the document reached. Parsing has stopped.

Function Documentation

void le_json_Cleanup

(

le_json_ParsingSessionRef_t

session

)

Stops parsing and cleans up memory allocated by the parser.

Warning

Be sure to stop parsing before closing the file descriptor.

Parameters

session

The parsing session to clean up (see le_json_Parse()).

size_t le_json_GetBytesRead

(

le_json_ParsingSessionRef_t

session

)

Returns

The number of bytes that have been read from the input stream so far.

Parameters

session

Parsing session.

const char* le_json_GetContextName

(

le_json_ContextType_t

context

)

Returns

Human readable string containing the name of a given JSON parsing context.

le_json_ContextType_t le_json_GetContextType

(

void

)

Get the type of parsing context that the parser is currently in.

Returns

The context type.

Warning

This function can only be called inside event or error handlers.

const char* le_json_GetEventName

(

le_json_Event_t

event

)

Returns

Human readable string containing the name of a given JSON parsing event.

double le_json_GetNumber

(

void

)

Fetches the value of a parsed number.

Warning

This function can only be called inside event handlers when LE_JSON_NUMBER events are being handled.

void* le_json_GetOpaquePtr

(

void

)

Get the opaque pointer attached to the parser.

Returns

The pointer previously set by le_json_Parse() or a subsequent call to le_json_SetOpaquePtr().

Warning

This function can only be called inside event or error handlers.

le_json_ParsingSessionRef_t le_json_GetSession

(

void

)

For use by an event handler or error handler to fetch the JSON parsing session reference for the session that called its handler function.

Returns

The session reference of the JSON parsing session.

Warning

This function can only be called inside event or error handlers.

const char* le_json_GetString

(

void

)

Fetches a pointer to a string value or object member name.

This pointer is only valid until the event handler returns.

Warning

This function can only be called inside event handlers when LE_JSON_OBJECT_MEMBER or LE_JSON_STRING events are being handled.

le_json_ParsingSessionRef_t le_json_Parse	(	int	fd,
		le_json_EventHandler_t	eventHandler,
		le_json_ErrorHandler_t	errorHandler,
		void *	opaquePtr
	)

Parse a JSON document received via a file descriptor.

Returns

Reference to the JSON parsing session started by this function call.

Parameters

fd	File descriptor to read the JSON document from.
eventHandler	Function to call when normal parsing events happen.
errorHandler	Function to call when errors happen.
opaquePtr	Opaque pointer to be fetched by handlers using le_json_GetOpaquePtr().

void le_json_SetErrorHandler

(

le_json_ErrorHandler_t

callbackFunc

)

Set the error handler function

Warning

This function can only be called inside event or error handlers.

Parameters

callbackFunc

Function to call when parsing errors happen.

void le_json_SetEventHandler

(

le_json_EventHandler_t

callbackFunc

)

Set the current context's event handler function.

Warning

This function can only be called inside event or error handlers.

Parameters

callbackFunc

Function to call when parsing events happen.

void le_json_SetOpaquePtr

(

void *

ptr

)

Set the opaque pointer attached to the parser.

Warning

This function can only be called inside event or error handlers.

Parameters

ptr	Opaque pointer to be fetched using le_json_GetOpaquePtr().