authorgravatar for samy2014@free.frsamy007 <samy2014@free.fr> 2025-03-24 22:05:57+01:00
committergravatar for samy2014@free.frsamy007 <samy2014@free.fr> 2025-03-24 22:05:57+01:00
logbe483dabc8fade06ad21b1e45c2bc731c4c4dd4f
treeb8e95591c17afdd822eb61ef6fe48dbaf6983b79
parent539f3effd38fac03cacd81338949650297071491

fix: Allocator.remap now handles zero-bytes sized types

2 files changed, 20 insertions(+), 0 deletions(-)

lib/std/mem.zig+12
...@@ -228,6 +228,18 @@ test "Allocator.resize" {...@@ -228,6 +228,18 @@ test "Allocator.resize" {
228 }228 }
229}229}
230230
231test "Allocator alloc and remap with zero-bit type" {
232 var values = try testing.allocator.alloc(void, 10);
233 defer testing.allocator.free(values);
234
235 try testing.expectEqual(10, values.len);
236 const remaped = testing.allocator.remap(values, 200);
237 try testing.expect(remaped != null);
238
239 values = remaped.?;
240 try testing.expectEqual(200, values.len);
241}
242
231/// Copy all of source into dest at position 0.243/// Copy all of source into dest at position 0.
232/// dest.len must be >= source.len.244/// dest.len must be >= source.len.
233/// If the slices overlap, dest.ptr must be <= src.ptr.245/// If the slices overlap, dest.ptr must be <= src.ptr.
lib/std/mem/Allocator.zig+8
...@@ -311,12 +311,15 @@ pub fn resize(self: Allocator, allocation: anytype, new_len: usize) bool {...@@ -311,12 +311,15 @@ pub fn resize(self: Allocator, allocation: anytype, new_len: usize) bool {
311/// `allocation` may be an empty slice, in which case a new allocation is made.311/// `allocation` may be an empty slice, in which case a new allocation is made.
312///312///
313/// `new_len` may be zero, in which case the allocation is freed.313/// `new_len` may be zero, in which case the allocation is freed.
314///
315/// If the allocation's elements' type is zero bytes sized, `allocation.len` is set to `new_len`.
314pub fn remap(self: Allocator, allocation: anytype, new_len: usize) t: {316pub fn remap(self: Allocator, allocation: anytype, new_len: usize) t: {
315 const Slice = @typeInfo(@TypeOf(allocation)).pointer;317 const Slice = @typeInfo(@TypeOf(allocation)).pointer;
316 break :t ?[]align(Slice.alignment) Slice.child;318 break :t ?[]align(Slice.alignment) Slice.child;
317} {319} {
318 const Slice = @typeInfo(@TypeOf(allocation)).pointer;320 const Slice = @typeInfo(@TypeOf(allocation)).pointer;
319 const T = Slice.child;321 const T = Slice.child;
322
320 const alignment = Slice.alignment;323 const alignment = Slice.alignment;
321 if (new_len == 0) {324 if (new_len == 0) {
322 self.free(allocation);325 self.free(allocation);
...@@ -325,6 +328,11 @@ pub fn remap(self: Allocator, allocation: anytype, new_len: usize) t: {...@@ -325,6 +328,11 @@ pub fn remap(self: Allocator, allocation: anytype, new_len: usize) t: {
325 if (allocation.len == 0) {328 if (allocation.len == 0) {
326 return null;329 return null;
327 }330 }
331 if (@sizeOf(T) == 0) {
332 var new_memory = allocation;
333 new_memory.len = new_len;
334 return new_memory;
335 }
328 const old_memory = mem.sliceAsBytes(allocation);336 const old_memory = mem.sliceAsBytes(allocation);
329 // I would like to use saturating multiplication here, but LLVM cannot lower it337 // I would like to use saturating multiplication here, but LLVM cannot lower it
330 // on WebAssembly: https://github.com/ziglang/zig/issues/9660338 // on WebAssembly: https://github.com/ziglang/zig/issues/9660