Changelog

All notable changes to this project will be documented in this file.

0.12.0 (2025-08-18)

Added

• Add yyjson_write_number() and yyjson_mut_write_number() to write a number value to a string buffer.
• Add YYJSON_READ_ALLOW_EXT_NUMBER to support extended number formats, such as 0x7B, +.123.
• Add YYJSON_READ_ALLOW_EXT_ESCAPE to support extended escape, such as \a, \0, \x7B.
• Add YYJSON_READ_ALLOW_EXT_WHITESPACE to support extended whitespace, such as \v, \u2028.
• Add YYJSON_READ_ALLOW_SINGLE_QUOTED_STR to support single-quoted strings, such as 'ab'.
• Add YYJSON_READ_ALLOW_UNQUOTED_KEY to allow unquoted keys, such as {a:1,b:2}.
• Add YYJSON_READ_JSON5 to enable full JSON5 support.

Changed

• Removed support for non-standard JSON in the incremental reader yyjson_incr_read().

0.11.1 (2025-05-14)

Fixed

• Fix errors when unaligned access is disallowed (no impact if your build was already successful).

0.11.0 (2025-05-05)

Added

• Add YYJSON_READ_ALLOW_BOM flag to allow UTF-8 BOM.
• Add YYJSON_WRITE_FP_TO_FLOAT flag to write real numbers using single-precison.
• Add YYJSON_WRITE_FP_TO_FIXED(prec) flag to write real numbers using fix-point notation.
• Add set_fp_to_float() and set_fp_to_fixed() functions to control the output format of a specific number.
• Add set_str_noesc() function to skip escaping for a specific string during writing.
• Add yyjson_incr_read(), yyjson_incr_new(), yyjson_incr_free() functions for incremental DOM reading.

Changed

• Rewrite the floating-point number to string functions with a new fast path.
• When comments are allowed, return UNEXPECTED_END instead of INVALID_COMMENT for unclosed comments.
• Truncated escape sequences now report the error position at the sequence start rather than the end.

Fixed

• Fix some warnings when directly including yyjson.c: #177
• Fix missing indent for YYJSON_TYPE_RAW in prettify function: #178
• Fix bug in yyjson_mut_arr_iter_remove(): #194
• Fix clang 19 documentation warnings.
• Fix cmake 4 and cmake 3.5 warnings.

0.10.0 (2024-07-09)

Added

• Add yyjson_locate_pos() function to locate the line and column number for error position: #166

Changed

• Improve error messages for JSON reader: #168

Fixed

• Fix YYJSON_READ_NUMBER_AS_RAW not overriding YYJSON_READ_BIGNUM_AS_RAW as per documentation: #170

0.9.0 (2024-04-08)

Added

• Add YYJSON_WRITE_NEWLINE_AT_END flag for JSON writer: #147

Changed

• Add auto-type conversion (uint<->sint) to yyjson_ptr_get_uint/sint(): #152

Fixed

• Fix incorrect output in environments lacking native bool type support: #161

0.8.0 (2023-09-13)

Added

• Add YYJSON_SUBTYPE_NOESC subtype to mark strings that do not need to be escaped.
• Add YYJSON_DISABLE_UTF8_VALIDATION flag to allow disable UTF-8 validation at compile-time.
• Add dynamic allocator API: yyjson_alc_dyn_new(), yyjson_alc_dyn_free().
• Add the missing yyjson_mut_obj_add_arr/obj() API: #140

Changed

• Improve the write performance of strings with YYJSON_SUBTYPE_NOESC.

Fixed

• Fix clang-16 valgrind fail: #134
• Fix compile break when both FAST_FP and READER are disabled

0.7.0 (2023-05-25)

Added

• Add YYJSON_WRITE_PRETTY_TWO_SPACES option to allow 2 spaces instead of 4 spaces when writing pretty JSON: #99
• Add YYJSON_READ_BIGNUM_AS_RAW option to read big numbers as raw strings: #124
• Add yyjson_get_num() function to convert and return any number value as double: #108
• Add support for Loongarch: #112
• Add functions to get type-specific values specified by JSON Pointer: #116
• Add functions to read/write JSON with file pointer FILE *: #122
• Add functions to support modifying memory pool size of yyjson_mut_doc.
• Add convenience functions iter_with() for creating iterator.
• Add functions to modify JSON using JSON Pointer, such as ptr_set() and ptr_remove().
• Add support for JSON Patch (RFC 6902).

Changed

• BREAKING CHANGE: Change the allocator's realloc function signature, add old_size parameter for custom allocator: #100
• BREAKING CHANGE: Change yyjson_read_number() function, add alc parameter.
• DEPRECATED: Deprecate get_pointer() functions, rename to ptr_get().
• Improve performance of yyjson_mut_write() function.

Fixed

• Fix inaccurate error code for truncated JSON: #103

0.6.0 (2022-12-12)

Added

• Add functions to modify the content of a JSON value, such as yyjson_set_int(yyjson_val *val, int num).
• Add functions to copy from mutable doc to immutable doc.
• Add functions to support renaming an object's key.
• Add the yyjson_read_number() function to parse numeric strings.
• Add a placeholder allocator if yyjson_alc_pool_init() fails.

Fixed

• Fix quite NaN on MIPS and HPPA arch.
• Fixed compile error before GCC 4.5, which doesn't support empty optional extended asm label.
• When the built-in floating point conversion is disabled, the sprintf() output for floating point numbers is missing a decimal point, for example 123 should be 123.0.

0.5.1 (2022-06-17)

Fixed

• Fix run-time error when compiling as cpp and 32-bit (g++-5 -m32 -fPIC) #85
• Fix incurrect output number format, remove unnecessary digits (e.g. 2.0e34 -> 2e34).

0.5.0 (2022-05-25)

Added

• Add LibFuzzer support.
• Add Doxygen support.
• Add functions to support serializing a single JSON value.
• Add yyjson_mut_doc_mut_copy(), yyjson_mut_val_mut_copy(), yyjson_mut_merge_patch() functions for mutable input.
• Add yyjson_equals() and yyjson_mut_equals() functions to compare two values.
• Add yyjson_mut_obj_remove_key() and yyjson_mut_obj_remove_keyn() functions to simplify key removal.
• Add YYJSON_READ_NUMBER_AS_RAW option and RAW type support.
• Add YYJSON_READ_ALLOW_INVALID_UNICODE and YYJSON_WRITE_ALLOW_INVALID_UNICODE options to allow invalid unicode.

Changed

• Change yyjson_mut_obj_remove() return type from bool to yyjson_mut_val *.
• Rewrite string serialization function, validate unicode encoding by default.
• Rewrite the JSON Pointer implementation, remove internal malloc() calls.

Fixed

• Make the code work correctly with setlocale() function and -ffast-math flag: #54
• Fix negative infinity literals read error: #64
• Fix non null-terminated string write error.
• Fix incorrect behavior of YYJSON_DISABLE_NON_STANDARD flag: #80

0.4.0 (2021-12-12)

Added

• Add YYJSON_WRITE_INF_AND_NAN_AS_NULL flag for JSON writer.
• Add yyjson_merge_patch() function for JSON Merge-Path API (RFC 7386).
• Add yyjson_mut_obj_replace() and yyjson_mut_obj_insert() functions for object modification.
• Add yyjson_obj_iter_get() and yyjson_mut_obj_iter_get() functions for faster object search.
• Add yyjson_version() function.

Changed

• Replace YYJSON_DISABLE_COMMENT_READER and YYJSON_DISABLE_INF_AND_NAN_READER with YYJSON_DISABLE_NON_STANDARD compile-time flag.
• Replace YYJSON_DISABLE_FP_READER and YYJSON_DISABLE_FP_WRITER with YYJSON_DISABLE_FAST_FP_CONV compile-time flag.

Fixed

• Fix compiler warning with -Wconversion
• Fix compiler error for GCC 4.4 (#53) and MSVC 6.0 (#55)

0.3.0 (2021-05-25)

Added

• Add JSON Pointer support.
• Add CMake install target.

Changed

• Improve performance for some architectures that don't support unaligned memory access.

Fixed

• Fix some compiler warnings for GCC and Clang.
• Fix MSVC build error on UWP (uninitialized local variable).
• Fix stream file reading error on some platforms.

0.2.0 (2020-12-12)

Added

• Add swift package manager support.

Changed

• Improve JSON reader performance for gcc.
• Improve double number reader performance with a fast path.
• Rewrite double number writer with Schubfach algorithm: #4.
• Strict UTF-8 validation for JSON reader.

Removed

• Remove YYJSON_READ_FASTFP compile-time flag.

Fixed

• Fix a compile error for old version gcc on linux: #7.

0.1.0 (2020-10-26)

Added

• Initial release.
• Add the basic JSON reader and writer (RFC 8259).
• Add CMake support.
• Add GitHub CI workflow.
• Add test code and test data.
• Add sanitizer and valgrind memory checker.
• Add API and DataStructure documentation.