json.h File Reference

JSON parsing and encoding. More...

Data Structures

struct  spdk_json_val
 
struct  spdk_json_object_decoder
 

Macros

#define SPDK_JSON_VAL_ANY   SPDK_JSON_VAL_INVALID
 
#define SPDK_JSON_PARSE_INVALID   -1
 Invalid JSON syntax.
 
#define SPDK_JSON_PARSE_INCOMPLETE   -2
 JSON was valid up to the end of the current buffer, but did not represent a complete JSON value.
 
#define SPDK_JSON_PARSE_MAX_DEPTH_EXCEEDED   -3
 
#define SPDK_JSON_PARSE_FLAG_DECODE_IN_PLACE   0x000000001
 Decode JSON strings and names in place (modify the input buffer).
 
#define SPDK_JSON_PARSE_FLAG_ALLOW_COMMENTS   0x000000002
 Allow parsing of comments. More...
 
#define SPDK_JSON_WRITE_FLAG_FORMATTED   0x00000001
 

Typedefs

typedef int(* spdk_json_decode_fn) (const struct spdk_json_val *val, void *out)
 
typedef int(* spdk_json_write_cb) (void *cb_ctx, const void *data, size_t size)
 

Enumerations

enum  spdk_json_val_type {
  SPDK_JSON_VAL_INVALID = 0, SPDK_JSON_VAL_NULL = 1U << 1, SPDK_JSON_VAL_TRUE = 1U << 2, SPDK_JSON_VAL_FALSE = 1U << 3,
  SPDK_JSON_VAL_NUMBER = 1U << 4, SPDK_JSON_VAL_STRING = 1U << 5, SPDK_JSON_VAL_ARRAY_BEGIN = 1U << 6, SPDK_JSON_VAL_ARRAY_END = 1U << 7,
  SPDK_JSON_VAL_OBJECT_BEGIN = 1U << 8, SPDK_JSON_VAL_OBJECT_END = 1U << 9, SPDK_JSON_VAL_NAME = 1U << 10
}
 

Functions

ssize_t spdk_json_parse (void *json, size_t size, struct spdk_json_val *values, size_t num_values, void **end, uint32_t flags)
 
int spdk_json_decode_object (const struct spdk_json_val *values, const struct spdk_json_object_decoder *decoders, size_t num_decoders, void *out)
 
int spdk_json_decode_array (const struct spdk_json_val *values, spdk_json_decode_fn decode_func, void *out, size_t max_size, size_t *out_size, size_t stride)
 
int spdk_json_decode_bool (const struct spdk_json_val *val, void *out)
 
int spdk_json_decode_uint16 (const struct spdk_json_val *val, void *out)
 
int spdk_json_decode_int32 (const struct spdk_json_val *val, void *out)
 
int spdk_json_decode_uint32 (const struct spdk_json_val *val, void *out)
 
int spdk_json_decode_uint64 (const struct spdk_json_val *val, void *out)
 
int spdk_json_decode_string (const struct spdk_json_val *val, void *out)
 
size_t spdk_json_val_len (const struct spdk_json_val *val)
 Get length of a value in number of values. More...
 
bool spdk_json_strequal (const struct spdk_json_val *val, const char *str)
 Compare JSON string with null terminated C string. More...
 
char * spdk_json_strdup (const struct spdk_json_val *val)
 Equivalent of strdup() for JSON string values. More...
 
int spdk_json_number_to_uint16 (const struct spdk_json_val *val, uint16_t *num)
 
int spdk_json_number_to_int32 (const struct spdk_json_val *val, int32_t *num)
 
int spdk_json_number_to_uint32 (const struct spdk_json_val *val, uint32_t *num)
 
int spdk_json_number_to_uint64 (const struct spdk_json_val *val, uint64_t *num)
 
struct spdk_json_write_ctx * spdk_json_write_begin (spdk_json_write_cb write_cb, void *cb_ctx, uint32_t flags)
 
int spdk_json_write_end (struct spdk_json_write_ctx *w)
 
int spdk_json_write_null (struct spdk_json_write_ctx *w)
 
int spdk_json_write_bool (struct spdk_json_write_ctx *w, bool val)
 
int spdk_json_write_int32 (struct spdk_json_write_ctx *w, int32_t val)
 
int spdk_json_write_uint32 (struct spdk_json_write_ctx *w, uint32_t val)
 
int spdk_json_write_int64 (struct spdk_json_write_ctx *w, int64_t val)
 
int spdk_json_write_uint64 (struct spdk_json_write_ctx *w, uint64_t val)
 
int spdk_json_write_string (struct spdk_json_write_ctx *w, const char *val)
 
int spdk_json_write_string_raw (struct spdk_json_write_ctx *w, const char *val, size_t len)
 
int spdk_json_write_string_utf16le (struct spdk_json_write_ctx *w, const uint16_t *val)
 Write null-terminated UTF-16LE string. More...
 
int spdk_json_write_string_utf16le_raw (struct spdk_json_write_ctx *w, const uint16_t *val, size_t len)
 Write UTF-16LE string. More...
 
int spdk_json_write_string_fmt (struct spdk_json_write_ctx *w, const char *fmt,...)
 
int spdk_json_write_string_fmt_v (struct spdk_json_write_ctx *w, const char *fmt, va_list args)
 
int spdk_json_write_array_begin (struct spdk_json_write_ctx *w)
 
int spdk_json_write_array_end (struct spdk_json_write_ctx *w)
 
int spdk_json_write_object_begin (struct spdk_json_write_ctx *w)
 
int spdk_json_write_object_end (struct spdk_json_write_ctx *w)
 
int spdk_json_write_name (struct spdk_json_write_ctx *w, const char *name)
 
int spdk_json_write_name_raw (struct spdk_json_write_ctx *w, const char *name, size_t len)
 
int spdk_json_write_val (struct spdk_json_write_ctx *w, const struct spdk_json_val *val)
 
int spdk_json_write_val_raw (struct spdk_json_write_ctx *w, const void *data, size_t len)
 
int spdk_json_write_named_null (struct spdk_json_write_ctx *w, const char *name)
 
int spdk_json_write_named_bool (struct spdk_json_write_ctx *w, const char *name, bool val)
 
int spdk_json_write_named_int32 (struct spdk_json_write_ctx *w, const char *name, int32_t val)
 
int spdk_json_write_named_uint32 (struct spdk_json_write_ctx *w, const char *name, uint32_t val)
 
int spdk_json_write_named_uint64 (struct spdk_json_write_ctx *w, const char *name, uint64_t val)
 
int spdk_json_write_named_int64 (struct spdk_json_write_ctx *w, const char *name, int64_t val)
 
int spdk_json_write_named_string (struct spdk_json_write_ctx *w, const char *name, const char *val)
 
int spdk_json_write_named_string_fmt (struct spdk_json_write_ctx *w, const char *name, const char *fmt,...)
 
int spdk_json_write_named_string_fmt_v (struct spdk_json_write_ctx *w, const char *name, const char *fmt, va_list args)
 
int spdk_json_write_named_array_begin (struct spdk_json_write_ctx *w, const char *name)
 
int spdk_json_write_named_object_begin (struct spdk_json_write_ctx *w, const char *name)
 
int spdk_json_find (struct spdk_json_val *object, const char *key_name, struct spdk_json_val **key, struct spdk_json_val **val, enum spdk_json_val_type type)
 Return JSON value asociated with key key_name. More...
 
int spdk_json_find_string (struct spdk_json_val *object, const char *key_name, struct spdk_json_val **key, struct spdk_json_val **val)
 The same as calling spdk_json_find() function with type set to SPDK_JSON_VAL_STRING. More...
 
int spdk_json_find_array (struct spdk_json_val *object, const char *key_name, struct spdk_json_val **key, struct spdk_json_val **value)
 The same as calling spdk_json_key() function with type set to SPDK_JSON_VAL_ARRAY_BEGIN. More...
 
struct spdk_json_valspdk_json_object_first (struct spdk_json_val *object)
 Return first JSON value in given JSON object. More...
 
struct spdk_json_valspdk_json_array_first (struct spdk_json_val *array_begin)
 Return first JSON value in array. More...
 
struct spdk_json_valspdk_json_next (struct spdk_json_val *pos)
 Advance to the next JSON value in JSON object or array. More...
 

Detailed Description

JSON parsing and encoding.

Macro Definition Documentation

◆ SPDK_JSON_PARSE_FLAG_ALLOW_COMMENTS

#define SPDK_JSON_PARSE_FLAG_ALLOW_COMMENTS   0x000000002

Allow parsing of comments.

Comments are not allowed by the JSON RFC, so this is not enabled by default.

Function Documentation

◆ spdk_json_array_first()

struct spdk_json_val* spdk_json_array_first ( struct spdk_json_val array_begin)

Return first JSON value in array.

Parameters
array_beginpointer to JSON array begin
Returns
Pointer to first JSON value or NULL if array is empty or is not an JSON array.

◆ spdk_json_find()

int spdk_json_find ( struct spdk_json_val object,
const char *  key_name,
struct spdk_json_val **  key,
struct spdk_json_val **  val,
enum spdk_json_val_type  type 
)

Return JSON value asociated with key key_name.

Subobjects won't be searched.

Parameters
objectJSON object to be examined
key_namename of the key
keyoptional, will be set with found key
valoptional, will be set with value of the key
typesearch for specific value type. Pass SPDK_JSON_VAL_ANY to match any type.
Returns
0 if found or negative error code: -EINVAL - json object is invalid -ENOENT - key not found -EDOM - key exists but value type mismatch.

◆ spdk_json_find_array()

int spdk_json_find_array ( struct spdk_json_val object,
const char *  key_name,
struct spdk_json_val **  key,
struct spdk_json_val **  value 
)

The same as calling spdk_json_key() function with type set to SPDK_JSON_VAL_ARRAY_BEGIN.

Parameters
objectJSON object to be examined
key_namename of the key
keyoptional, will be set with found key
valueoptional, will be set with key value
Returns
See spdk_json_find

◆ spdk_json_find_string()

int spdk_json_find_string ( struct spdk_json_val object,
const char *  key_name,
struct spdk_json_val **  key,
struct spdk_json_val **  val 
)

The same as calling spdk_json_find() function with type set to SPDK_JSON_VAL_STRING.

Parameters
objectJSON object to be examined
key_namename of the key
keyoptional, will be set with found key
valoptional, will be set with value of the key
Returns
See spdk_json_find

◆ spdk_json_next()

struct spdk_json_val* spdk_json_next ( struct spdk_json_val pos)

Advance to the next JSON value in JSON object or array.

Warning
if pos is not JSON key or JSON array element behaviour is undefined.
Parameters
pospointer to JSON key if iterating over JSON object or array element
Returns
next JSON value or NULL if there is no more objects or array elements

◆ spdk_json_object_first()

struct spdk_json_val* spdk_json_object_first ( struct spdk_json_val object)

Return first JSON value in given JSON object.

Parameters
objectpointer to JSON object begin
Returns
Pointer to first object or NULL if object is empty or is not an JSON object

◆ spdk_json_strdup()

char* spdk_json_strdup ( const struct spdk_json_val val)

Equivalent of strdup() for JSON string values.

If val is not representable as a C string (contains embedded '\0' characters), returns NULL.

Caller is responsible for passing the result to free() when it is no longer needed.

◆ spdk_json_strequal()

bool spdk_json_strequal ( const struct spdk_json_val val,
const char *  str 
)

Compare JSON string with null terminated C string.

Returns
true if strings are equal or false if not

◆ spdk_json_val_len()

size_t spdk_json_val_len ( const struct spdk_json_val val)

Get length of a value in number of values.

This can be used to skip over a value while interpreting parse results.

For SPDK_JSON_VAL_ARRAY_BEGIN and SPDK_JSON_VAL_OBJECT_BEGIN, this returns the number of values contained within this value, plus the _BEGIN and _END values.

For all other values, this returns 1.

◆ spdk_json_write_string_utf16le()

int spdk_json_write_string_utf16le ( struct spdk_json_write_ctx *  w,
const uint16_t *  val 
)

Write null-terminated UTF-16LE string.

Parameters
wJSON write context.
valUTF-16LE string; must be null terminated.
Returns
0 on success or negative on failure.

◆ spdk_json_write_string_utf16le_raw()

int spdk_json_write_string_utf16le_raw ( struct spdk_json_write_ctx *  w,
const uint16_t *  val,
size_t  len 
)

Write UTF-16LE string.

Parameters
wJSON write context.
valUTF-16LE string; may contain embedded null characters.
lenLength of val in 16-bit code units (i.e. size of string in bytes divided by 2).
Returns
0 on success or negative on failure.