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std/mem ​

Memory mapping and bump allocation primitives.

This is the raw bump allocator. For a generational arena with typed Handle<T>, see std/arena — that module owns the name Arena.

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from "std/mem" import { MappedMemory, Bump, mmapAnon, mmapFile }

Types ​

MappedMemory ​

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struct MappedMemory {
    ptr: i64,
    len: i64,
}

A region of memory-mapped address space.

Bump ​

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struct Bump {
    base: i64,
    cap: i64,
    used: i64,
}

A bump allocator backed by a contiguous heap region. All allocations are 8-byte aligned and the whole region is freed on drop.

Functions ​

mmapAnon ​

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fn mmapAnon(len: i64): Result<MappedMemory>

Maps len bytes of anonymous (zero-filled) memory.

mmapFile ​

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fn mmapFile(fd: i32, len: i64): Result<MappedMemory>

Memory-maps len bytes from file descriptor fd.

Bump.new ​

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fn Bump.new(capacity: i64): Result<Bump>

Creates a bump allocator with the given byte capacity.

Bump.alloc ​

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fn Bump.alloc(self: &mut Bump, size: i64): Result<i64>

Bump-allocates size bytes, returning a pointer. Fails if the allocator is full.

Bump.reset ​

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fn Bump.reset(self: &mut Bump): void

Resets the used counter to zero, reclaiming every allocation at once.

Bump.remaining ​

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fn Bump.remaining(self: &Bump): i64

Bytes still available.