JSON

Utilities

Get the current parent Object or Array token.

This returns the current parent Object or Array token.

Parameters

context

Pointer to initialized context

Returns

pointer to parent token, NULL else

Retrieve a token from the JSON context.

After calling gos_json_parse_chunked(), the gos_json_parse_context_t may have one or more tokens. This retrieves a given token from the context.

If the 'str_val' parameter is specified then this finds the first string token with the given value. If the 'offset_tok' parameter is specified then it starts searching from 'offset_tok' token onward. If both parameters are NULL then return the head token. If the token isn't found or there are no tokens in the context then return NULL.

Note

This returns a 'token'. It has no concept of key/value. Refer to gos_json_context_get_value() if the value of a given key is required.

Parameters

context	Initialized JSON context
str_val	Optional string value to search for, leave NULL if unused
offset_tok	Starting token to begin search, leave NULL if unused

Returns

pointer to found token, NULL else

Examples:

network/http_server/requests/json_parser.c, utility/json_parser/parse_all_examples.c, utility/json_parser/parse_example1.c, and utility/json_parser/parse_example3.c.

Return the value token for a specified key.

After calling json_parse_chunked(), the gos_json_parse_context_t may have one or more tokens. This returns a corresponding value token for the specified key.

This searches linearly starting at the first token in the context (or 'offset_tok' if supplied) for the first GOS_JSON_TYPE_STRING token with its value equal to 'str_key'. It then returns the key token's value (i.e. the token following the found key token).

If the key token is not found or the context is empty then NULL is returned.

Note

'offset_tok' must be either a GOS_JSON_TYPE_OBJECT or GOS_JSON_TYPE_ARRAY. If it's any other type, the API will automatically begin searching for a GOS_JSON_TYPE_OBJECT or GOS_JSON_TYPE_ARRAY starting at offset_tok.

Parameters

context	Initialized JSON context
str_key	String key value to search
offset_tok	Starting token to begin search, leave NULL if unused

Returns

pointer to value of found key token, NULL else

Examples:

utility/json_parser/parse_example2.c.

Skip past specified number of tokens in context.

After calling json_parse_chunked(), the gos_json_parse_context_t may have one or more tokens. This is a helper API for skipping past a specified number of tokens.

If current_tok is given as an argument, then this will return current_tok + count tokens. If current_tok is NOT given, then this will return the first token in the context + count tokens. If the count token is not available then this returns NULL.

Parameters

context	Initialized JSON context
current_tok	Optional token to begin from, begin from first token in context otherwise
count	Number of tokens to skip

Returns

pointer to first token after skipped tokens, NULL if not available

Decoding delimited JSON data to original representation.

The decoding is done in-place. The gos_buffer_t will be updated to reflect the new data size.

Parameters

fragment

Buffer contain data to JSON decode

Returns

result of decoding

Delimit any JSON special characters in supplied buffer.

This backslash delimits any special JSON characters in the supplied buffer data in-place. The given buffer must be larger enough to hold the additional backslash characters (if necessary). The size of the gos_buffer_t will be updated to reflect the new data size.

Parameters

fragment

Buffer hold data to JSON encode, buffer must be large enough to hold additional backslash characters

Parse JSON formatted data in chunks.

This will parse JSON data and optionally allocate tokens. This may be called multiple times for a given set of JSON data.

Call json_parse_context_init() first to initialize a parsing context.

After parsing call json_context_get_token() to retrieve a token.

Parameters

context	Previously initialize JSON context
user	Optional user data to be passed to gos_json_parse_reader_t and gos_json_token_callback_t

Returns

gos_result_t result of api call

Examples:

network/http_server/requests/json_parser.c, utility/json_parser/parse_all_examples.c, utility/json_parser/parse_example1.c, utility/json_parser/parse_example2.c, utility/json_parser/parse_example3.c, and utility/json_parser/parse_example9.c.

Cleanup JSON parser context.

This cleans up the allocated parsing context. This also de-allocates any allocated tokens from parsing.

Parameters

context

JSON parsing context to de-initialize

Returns

gos_result_t result of api call

Examples:

network/http_server/requests/json_parser.c, utility/json_parser/parse_all_examples.c, utility/json_parser/parse_example1.c, utility/json_parser/parse_example2.c, utility/json_parser/parse_example3.c, and utility/json_parser/parse_example9.c.

Initialize JSON parsing context.

This allocates a JSON parsing context configured with the given configuration.

Call json_parse_context_deinit() to cleanup this context.

Parameters

context_ptr	Pointer to hold pointer to allocated context
config	Context configuration

Returns

gos_result_t result of api call

Examples:

network/http_server/requests/json_parser.c, utility/json_parser/parse_all_examples.c, utility/json_parser/parse_example1.c, utility/json_parser/parse_example2.c, utility/json_parser/parse_example3.c, and utility/json_parser/parse_example9.c.