BSON_DECIMAL128_T(3)

🌸 BSON Decimal128 Abstraction 🌸

okay bestie, so this is the BSON_DECIMAL128_T(3) page from libbson — it's giving "tiny struct, huge personality" and honestly it ate 💅

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✨ SYNOPSIS ✨

first things first, you gotta pull in the header, no cap:

#include <bson/bson.h>

then boom, these defines are your besties:

#define BSON_DECIMAL128_STRING 43
#define BSON_DECIMAL128_INF "Infinity"
#define BSON_DECIMAL128_NAN "NaN"

and here's the actual struct, look at her 👑

typedef struct {
#if BSON_BYTE_ORDER == BSON_LITTLE_ENDIAN
   uint64_t low;
   uint64_t high;
#elif BSON_BYTE_ORDER == BSON_BIG_ENDIAN
   uint64_t high;
   uint64_t low;
#endif
} bson_decimal128_t;

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💖 DESCRIPTION 💖

so the bson_decimal128_t structure is literally the IEEE-754 Decimal128 data type, periodt. she's an aggregate that holds two uint64_ts, named high and low — iconic duo fr fr 🫶

here's the tea though: the declaration and layout order between them depends on the endian order of the target platform. and the way that works is:

• low will always correspond to the low-order bits of the Decimal128 object 🌸
• high corresponds to the high-order bits ⭐

and like, the bson_decimal128_t always has a size of sixteen (16) — yes, always — and can be bit-cast to/from a _Decimal128. no notes, she's just built different 💀✨

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🎀 EXAMPLE 🎀

here's a whole little program, go off:

#include <bson/bson.h>
#include <stdio.h>

int
main (int argc, char *argv[])
{
   char string[BSON_DECIMAL128_STRING];
   bson_decimal128_t decimal128;

   bson_decimal128_from_string ("100.00", &decimal128);
   bson_decimal128_to_string (&decimal128, string);
   printf ("Decimal128 value: %s\n", string);

   return 0;
}

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👑 AUTHOR 👑

MongoDB, Inc — the main characters, honestly 🧚

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🌈 COPYRIGHT 🌈

2009-present, MongoDB, Inc. 💜

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okay that's the whole vibe check bestie, hope this slayed for you 🦋

and since we can't forget the footer: this page is from libbson version 2.5.6, dated Oct 09, 2026 — screenshot it, bookmark it, tape it to your mirror, whatever works 💖🎀✨