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* JSON data structures are defined at:
* [1]
* [2]
* The JSON-writer API allows one to build JSON data structures using a
* simple wrapper around a "struct strbuf" buffer. It is intended as a
* simple API to build output strings; it is not intended to be a general
* object model for JSON data. In particular, it does not re-order keys
* in an object (dictionary), it does not de-dup keys in an object, and
* it does not allow lookup or parsing of JSON data.
* All string values (both keys and string r-values) are properly quoted
* and escaped if they contain special characters.
* These routines create compact JSON data (with no unnecessary whitespace,
* newlines, or indenting). If you get an unexpected response, verify
* that you're not expecting a pretty JSON string.
* Both "JSON objects" (aka sets of k/v pairs) and "JSON array" can be
* constructed using a 'begin append* end' model.
* Nested objects and arrays can either be constructed bottom up (by
* creating sub object/arrays first and appending them to the super
* object/array) -or- by building them inline in one pass. This is a
* personal style and/or data shape choice.
* See t/helper/test-json-writer.c for various usage examples.
* ============
* The JSON specification [1,2] defines string values as Unicode data
* and probably UTF-8 encoded. The current json-writer API does not
* enforce this and will write any string as received. However, it will
* properly quote and backslash-escape them as necessary. It is up to
* the caller to UTF-8 encode their strings *before* passing them to this
* API. This layer should not have to try to guess the encoding or locale
* of the given strings.
#include "strbuf.h"
struct json_writer
* Buffer of the in-progress JSON currently being composed.
struct strbuf json;
* Simple stack of the currently open array and object forms.
* This is a string of '{' and '[' characters indicating the
* currently unterminated forms. This is used to ensure the
* properly closing character is used when popping a level and
* to know when the JSON is completely closed.
struct strbuf open_stack;
unsigned int need_comma:1;
unsigned int pretty:1;
#define JSON_WRITER_INIT { \
.json = STRBUF_INIT, \
.open_stack = STRBUF_INIT, \
void jw_init(struct json_writer *jw);
void jw_release(struct json_writer *jw);
void jw_object_begin(struct json_writer *jw, int pretty);
void jw_array_begin(struct json_writer *jw, int pretty);
void jw_object_string(struct json_writer *jw, const char *key,
const char *value);
void jw_object_intmax(struct json_writer *jw, const char *key, intmax_t value);
void jw_object_double(struct json_writer *jw, const char *key, int precision,
double value);
void jw_object_true(struct json_writer *jw, const char *key);
void jw_object_false(struct json_writer *jw, const char *key);
void jw_object_bool(struct json_writer *jw, const char *key, int value);
void jw_object_null(struct json_writer *jw, const char *key);
void jw_object_sub_jw(struct json_writer *jw, const char *key,
const struct json_writer *value);
void jw_object_inline_begin_object(struct json_writer *jw, const char *key);
void jw_object_inline_begin_array(struct json_writer *jw, const char *key);
void jw_array_string(struct json_writer *jw, const char *value);
void jw_array_intmax(struct json_writer *jw, intmax_t value);
void jw_array_double(struct json_writer *jw, int precision, double value);
void jw_array_true(struct json_writer *jw);
void jw_array_false(struct json_writer *jw);
void jw_array_bool(struct json_writer *jw, int value);
void jw_array_null(struct json_writer *jw);
void jw_array_sub_jw(struct json_writer *jw, const struct json_writer *value);
void jw_array_argc_argv(struct json_writer *jw, int argc, const char **argv);
void jw_array_argv(struct json_writer *jw, const char **argv);
void jw_array_inline_begin_object(struct json_writer *jw);
void jw_array_inline_begin_array(struct json_writer *jw);
int jw_is_terminated(const struct json_writer *jw);
void jw_end(struct json_writer *jw);
#endif /* JSON_WRITER_H */