Function resize [src]

Request to modify the size of an allocation. It is guaranteed to not move the pointer, however the allocator implementation may refuse the resize request by returning false. allocation may be an empty slice, in which case a new allocation is made. new_len may be zero, in which case the allocation is freed.

Prototype

pub fn resize(self: Allocator, allocation: anytype, new_len: usize) bool

Parameters

self: Allocatornew_len: usize

Source

  pub fn resize(self: Allocator, allocation: anytype, new_len: usize) bool {
    const Slice = @typeInfo(@TypeOf(allocation)).pointer;
    const T = Slice.child;
    const alignment = Slice.alignment;
    if (new_len == 0) {
        self.free(allocation);
        return true;
    }
    if (allocation.len == 0) {
        return false;
    }
    const old_memory = mem.sliceAsBytes(allocation);
    // I would like to use saturating multiplication here, but LLVM cannot lower it
    // on WebAssembly: https://github.com/ziglang/zig/issues/9660
    //const new_len_bytes = new_len *| @sizeOf(T);
    const new_len_bytes = math.mul(usize, @sizeOf(T), new_len) catch return false;
    return self.rawResize(old_memory, .fromByteUnits(alignment), new_len_bytes, @returnAddress());
}  