mirrors/zig
1
0
Fork 0
mirror of https://codeberg.org/ziglang/zig.git synced 2025-12-06 13:54:21 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

std.mem.Allocator: add dupeSentinel

Browse source 
Here, because `dupeZ` is used a lot for null-terminated strings,
I believe it should stay. However, generic sentinel termination
would still be useful for, as I did in the test, making a `null`-terminated
slice of pointers. Could be useful especially for interacting
with c code.
This commit is contained in:
Rue04 2025-11-27 22:22:23 +01:00
parent c07041a253
commit c0e3fa32a9
2 changed files with 18 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
lib/std/mem.zig
View file

@ -4898,9 +4898,15 @@ test isAligned {
try testing.expect(!isAligned(4, 16));
}
test "freeing empty string with null-terminated sentinel" {
const empty_string = try testing.allocator.dupeZ(u8, "");
testing.allocator.free(empty_string);
test "freeing empty slices with sentinel termination" {
const gpa = testing.allocator;
const empty_string = try gpa.dupeZ(u8, "");
gpa.free(empty_string);
const empty_integers = try gpa.dupeSentinel(u4, &.{}, 0xf);
gpa.free(empty_integers);
const empty_pointers = try gpa.dupeSentinel(?*anyopaque, &.{}, null);
gpa.free(empty_pointers);
}
/// Returns a slice with the given new alignment,

13
lib/std/mem/Allocator.zig
View file

@ -452,12 +452,17 @@ pub fn dupe(allocator: Allocator, comptime T: type, m: []const T) Error![]T {
return new_buf;
}
/// Copies `m` to newly allocated memory, with a null-terminated element. Caller owns the memory.
pub fn dupeZ(allocator: Allocator, comptime T: type, m: []const T) Error![:0]T {
/// Copies `m` to newly allocated memory, with a sentinel-terminated element. Caller owns the memory.
pub fn dupeSentinel(allocator: Allocator, comptime T: type, m: []const T, comptime sentinel: T) Error![:sentinel]T {
const new_buf = try allocator.alloc(T, m.len + 1);
@memcpy(new_buf[0..m.len], m);
new_buf[m.len] = 0;
return new_buf[0..m.len :0];
new_buf[m.len] = sentinel;
return new_buf[0..m.len :sentinel];
}
/// Copies `m` to newly allocated memory, with a null-terminated element. Caller owns the memory.
pub fn dupeZ(allocator: Allocator, comptime T: type, m: []const T) Error![:0]T {
return dupeSentinel(allocator, T, m, 0);
}
/// An allocator that always fails to allocate.