A high performance JSON library written in ANSI C.
- Fast: can read or write gigabytes per second JSON data on modern CPU.
- Portable: compliant with ANSI C (C89).
- Standard: compliant with RFC 8259 and ECMA-404 standard.
- Safe: complete JSON form, number format and UTF-8 validation.
- Accuracy: can read and write
int64
,uint64
anddouble
number accurately. - No Limit: support large data size, unlimited JSON level,
\u0000
string. - Extendable: options to allow comments, trailing commas, nan/inf, custom memory allocator.
- Developer Friendly: only one
h
and onec
file, easy to use API.
Benchmark project and dataset: yyjson_benchmark
twitter.json | parse (GB/s) | stringify (GB/s) |
---|---|---|
yyjson(insitu) | 1.80 | 1.51 |
yyjson | 1.72 | 1.42 |
simdjson | 1.52 | 0.61 |
sajson | 1.16 | |
rapidjson(insitu) | 0.77 | |
rapidjson(utf8) | 0.26 | 0.39 |
cjson | 0.32 | 0.17 |
jansson | 0.05 | 0.11 |
twitter.json | parse (GB/s) | stringify (GB/s) |
---|---|---|
yyjson(insitu) | 3.51 | 2.41 |
yyjson | 2.39 | 2.01 |
simdjson | 2.19 | 0.80 |
sajson | 1.74 | |
rapidjson(insitu) | 0.75 | |
rapidjson(utf8) | 0.30 | 0.58 |
cjson | 0.48 | 0.33 |
jansson | 0.09 | 0.24 |
More benchmark reports with interactive charts (update 2020-12-12)
Platform | CPU | Compiler | OS | Report |
---|---|---|---|---|
Intel NUC 8i5 | Core i5-8259U | msvc 2019 | Windows 10 2004 | Charts |
Intel NUC 8i5 | Core i5-8259U | clang 10.0 | Ubuntu 20.04 | Charts |
Intel NUC 8i5 | Core i5-8259U | gcc 9.3 | Ubuntu 20.04 | Charts |
AWS EC2 c5a.large | AMD EPYC 7R32 | gcc 9.3 | Ubuntu 20.04 | Charts |
AWS EC2 t4g.medium | Graviton2 (ARM64) | gcc 9.3 | Ubuntu 20.04 | Charts |
Apple iPhone 12 Pro | A14 (ARM64) | clang 12.0 | iOS 14 | Charts |
- A modern processor with:
- high instruction level parallelism
- excellent branch predictor
- low penalty for misaligned memory access
- A modern compiler with good optimization.
Just copy yyjson.h
and yyjson.c
to your project and start using it.
Since yyjson is ANSI C compatible, no other configuration is needed typically.
We have tested yyjson
with the following compilers: gcc, clang, msvc, icc, tcc. If you find a compile error, please report a bug.
yyjson includes all features by default, but you can trim out some of them by adding compile flags to get higher performance and/or smaller binary. See compile flags for details.
Clone repository and create build directory:
git clone https://github.com/ibireme/yyjson.git
mkdir build
cd build
Build static library:
cmake ..
cmake --build .
Build static library and run tests:
cmake .. -DYYJSON_BUILD_TESTS=ON
cmake --build .
ctest
Supported CMake options:
-DYYJSON_BUILD_TESTS=ON
Build all tests.-DBUILD_SHARED_LIBS=ON
Build shared library instead of static library.-DYYJSON_ENABLE_COVERAGE=ON
Enable code coverage for tests.-DYYJSON_ENABLE_VALGRIND=ON
Enable valgrind memory checker for tests.-DYYJSON_ENABLE_SANITIZE=ON
Enable sanitizer for tests.-DYYJSON_DISABLE_READER=ON
Disable JSON reader if you don't need it.-DYYJSON_DISABLE_WRITER=ON
Disable JSON writer if you don't need it.-DYYJSON_DISABLE_FP_READER=ON
Disable custom double number reader to reduce binary size.-DYYJSON_DISABLE_FP_WRITER=ON
Disable custom double number writer to reduce binary size.-DYYJSON_DISABLE_COMMENT_READER=ON
Disable non-standard comment support at compile time.-DYYJSON_DISABLE_INF_AND_NAN_READER=ON
Disable non-standard nan/inf support at compile time.
See compile flags for details.
const char *json = "{\"name\":\"Mash\",\"star\":4,\"hits\":[2,2,1,3]}";
yyjson_doc *doc = yyjson_read(json, strlen(json), 0);
yyjson_val *root = yyjson_doc_get_root(doc);
yyjson_val *name = yyjson_obj_get(root, "name");
printf("name: %s\n", yyjson_get_str(name));
printf("name length:%d\n", (int)yyjson_get_len(name));
yyjson_val *star = yyjson_obj_get(root, "star");
printf("star: %d\n", (int)yyjson_get_int(star));
yyjson_val *hits = yyjson_obj_get(root, "hits");
size_t idx, max;
yyjson_val *hit;
yyjson_arr_foreach(hits, idx, max, hit) {
printf("hit%d: %d\n", (int)idx, (int)yyjson_get_int(hit));
}
yyjson_doc_free(doc);
yyjson_mut_doc *doc = yyjson_mut_doc_new(NULL);
yyjson_mut_val *root = yyjson_mut_obj(doc);
yyjson_mut_doc_set_root(doc, root);
yyjson_mut_obj_add_str(doc, root, "name", "Mash");
yyjson_mut_obj_add_int(doc, root, "star", 4);
int hits_arr[] = {2, 2, 1, 3};
yyjson_mut_val *hits = yyjson_mut_arr_with_sint32(doc, hits_arr, 4);
yyjson_mut_obj_add_val(doc, root, "hits", hits);
const char *json = yyjson_mut_write(doc, 0, NULL);
if (json) {
printf("json: %s\n", json); // {"name":"Mash","star":4,"hits":[2,2,1,3]}
free((void *)json);
}
yyjson_mut_doc_free(doc);
yyjson_read_err err;
yyjson_read_flag flg = YYJSON_READ_ALLOW_COMMENTS | YYJSON_READ_ALLOW_TRAILING_COMMAS;
yyjson_doc *doc = yyjson_read_file("/tmp/test.json", flg, NULL, &err);
if (doc) {
yyjson_val *obj = yyjson_doc_get_root(doc);
yyjson_obj_iter iter;
yyjson_obj_iter_init(obj, &iter);
yyjson_val *key, *val;
while ((key = yyjson_obj_iter_next(&iter))) {
val = yyjson_obj_iter_get_val(key);
printf("%s: %s\n", yyjson_get_str(key), yyjson_get_type_desc(val));
}
yyjson_doc_free(doc);
} else {
printf("read error: %s at position: %ld\n", err.msg, err.pos);
}
yyjson_mut_doc *doc = yyjson_mut_read_file("/tmp/test.json", 0, NULL, NULL);
yyjson_mut_val *obj = yyjson_mut_doc_get_root(doc);
yyjson_mut_obj_iter iter;
yyjson_mut_obj_iter_init(obj, &iter);
yyjson_mut_val *key, *val;
while ((key = yyjson_mut_obj_iter_next(&iter))) {
val = yyjson_mut_obj_iter_get_val(key);
if (yyjson_mut_is_null(val)) {
yyjson_mut_obj_iter_remove(&iter);
}
}
yyjson_write_err err;
yyjson_write_flag flg = YYJSON_WRITE_PRETTY | YYJSON_WRITE_ESCAPE_UNICODE;
yyjson_mut_write_file("/tmp/test.json", doc, flg, NULL, &err);
if (err.code) {
printf("write error: %d, message: %s\n", err.code, err.msg);
}
yyjson_mut_doc_free(doc);
- Add documentation page.
- Add GitHub workflow for CI and codecov.
- Add more tests: valgrind, sanitizer.
- Support JSON Pointer to query value from document.
- Add fuzzer.
- Add
RAW
type for JSON reader and writer. - Add streaming API for JSON reader and writer.
- Add documentation about performance.
- Optimize performance for 32-bit processor.
This project is released under the MIT license.