| ... | ... | @@ -148,12 +148,56 @@ const CAllocator = struct { |
| 148 | 148 | } |
| 149 | 149 | }; |
| 150 | 150 | |
| 151 | /// Supports the full Allocator interface, including alignment, and exploiting |
| 152 | /// `malloc_usable_size` if available. For an allocator that directly calls |
| 153 | /// `malloc`/`free`, see `raw_c_allocator`. |
| 151 | 154 | pub const c_allocator = &c_allocator_state; |
| 152 | 155 | var c_allocator_state = Allocator{ |
| 153 | 156 | .allocFn = CAllocator.alloc, |
| 154 | 157 | .resizeFn = CAllocator.resize, |
| 155 | 158 | }; |
| 156 | 159 | |
| 160 | /// Asserts allocations are within `@alignOf(std.c.max_align_t)` and directly calls |
| 161 | /// `malloc`/`free`. Does not attempt to utilize `malloc_usable_size`. |
| 162 | /// This allocator is safe to use as the backing allocator with |
| 163 | /// `ArenaAllocator` and `GeneralPurposeAllocator`, and is more optimal in these cases |
| 164 | /// than to using `c_allocator`. |
| 165 | pub const raw_c_allocator = &raw_c_allocator_state; |
| 166 | var raw_c_allocator_state = Allocator{ |
| 167 | .allocFn = rawCAlloc, |
| 168 | .resizeFn = rawCResize, |
| 169 | }; |
| 170 | |
| 171 | fn rawCAlloc( |
| 172 | self: *Allocator, |
| 173 | len: usize, |
| 174 | ptr_align: u29, |
| 175 | len_align: u29, |
| 176 | ret_addr: usize, |
| 177 | ) Allocator.Error![]u8 { |
| 178 | assert(ptr_align <= @alignOf(std.c.max_align_t)); |
| 179 | const ptr = @ptrCast([*]u8, c.malloc(len) orelse return error.OutOfMemory); |
| 180 | return ptr[0..len]; |
| 181 | } |
| 182 | |
| 183 | fn rawCResize( |
| 184 | self: *Allocator, |
| 185 | buf: []u8, |
| 186 | old_align: u29, |
| 187 | new_len: usize, |
| 188 | len_align: u29, |
| 189 | ret_addr: usize, |
| 190 | ) Allocator.Error!usize { |
| 191 | if (new_len == 0) { |
| 192 | c.free(buf.ptr); |
| 193 | return 0; |
| 194 | } |
| 195 | if (new_len <= buf.len) { |
| 196 | return mem.alignAllocLen(buf.len, new_len, len_align); |
| 197 | } |
| 198 | return error.OutOfMemory; |
| 199 | } |
| 200 | |
| 157 | 201 | /// This allocator makes a syscall directly for every allocation and free. |
| 158 | 202 | /// Thread-safe and lock-free. |
| 159 | 203 | pub const page_allocator = if (std.Target.current.isWasm()) |
| ... | ... | @@ -804,6 +848,12 @@ test "c_allocator" { |
| 804 | 848 | } |
| 805 | 849 | } |
| 806 | 850 | |
| 851 | test "raw_c_allocator" { |
| 852 | if (builtin.link_libc) { |
| 853 | try testAllocator(raw_c_allocator); |
| 854 | } |
| 855 | } |
| 856 | |
| 807 | 857 | test "WasmPageAllocator internals" { |
| 808 | 858 | if (comptime std.Target.current.isWasm()) { |
| 809 | 859 | const conventional_memsize = WasmPageAllocator.conventional.totalPages() * mem.page_size; |
| ... | ... | @@ -958,6 +1008,7 @@ test "ThreadSafeFixedBufferAllocator" { |
| 958 | 1008 | try testAllocatorAlignedShrink(&fixed_buffer_allocator.allocator); |
| 959 | 1009 | } |
| 960 | 1010 | |
| 1011 | /// This one should not try alignments that exceed what C malloc can handle. |
| 961 | 1012 | pub fn testAllocator(base_allocator: *mem.Allocator) !void { |
| 962 | 1013 | var validationAllocator = mem.validationWrap(base_allocator); |
| 963 | 1014 | const allocator = &validationAllocator.allocator; |
Andrew Kelley <andrew@ziglang.org> 2020-11-18 22:09:34-07:00