xref: /aosp_15_r20/external/skia/src/base/SkContainers.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 // Copyright 2019 Google LLC.
2 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3 
4 #include "include/private/base/SkContainers.h"
5 
6 #include "include/private/base/SkAlign.h"
7 #include "include/private/base/SkAssert.h"
8 #include "include/private/base/SkMalloc.h"
9 #include "include/private/base/SkTo.h"
10 
11 #include <algorithm>
12 #include <cstddef>
13 
14 namespace {
15 // Return at least as many bytes to keep malloc aligned.
16 constexpr size_t kMinBytes = alignof(max_align_t);
17 
complete_size(void * ptr,size_t size)18 SkSpan<std::byte> complete_size(void* ptr, size_t size) {
19     if (ptr == nullptr) {
20         return {};
21     }
22 
23     return {static_cast<std::byte*>(ptr), sk_malloc_size(ptr, size)};
24 }
25 }  // namespace
26 
allocate(int capacity,double growthFactor)27 SkSpan<std::byte> SkContainerAllocator::allocate(int capacity, double growthFactor) {
28     SkASSERT(capacity >= 0);
29     SkASSERT(growthFactor >= 1.0);
30     SkASSERT_RELEASE(capacity <= fMaxCapacity);
31 
32     if (growthFactor > 1.0 && capacity > 0) {
33         capacity = this->growthFactorCapacity(capacity, growthFactor);
34     }
35 
36     return sk_allocate_throw(capacity * fSizeOfT);
37 }
38 
roundUpCapacity(int64_t capacity) const39 size_t SkContainerAllocator::roundUpCapacity(int64_t capacity) const {
40     SkASSERT(capacity >= 0);
41 
42     // If round will not go above fMaxCapacity return rounded capacity.
43     if (capacity < fMaxCapacity - kCapacityMultiple) {
44         return SkAlignTo(capacity, kCapacityMultiple);
45     }
46 
47     return SkToSizeT(fMaxCapacity);
48 }
49 
growthFactorCapacity(int capacity,double growthFactor) const50 size_t SkContainerAllocator::growthFactorCapacity(int capacity, double growthFactor) const {
51     SkASSERT(capacity >= 0);
52     SkASSERT(growthFactor >= 1.0);
53     // Multiply by the growthFactor. Remember this must be done in 64-bit ints and not
54     // size_t because size_t changes.
55     const int64_t capacityGrowth = static_cast<int64_t>(capacity * growthFactor);
56 
57     // Notice that for small values of capacity, rounding up will provide most of the growth.
58     return this->roundUpCapacity(capacityGrowth);
59 }
60 
61 
sk_allocate_canfail(size_t size)62 SkSpan<std::byte> sk_allocate_canfail(size_t size) {
63     // Make sure to ask for at least the minimum number of bytes.
64     const size_t adjustedSize = std::max(size, kMinBytes);
65     void* ptr = sk_malloc_canfail(adjustedSize);
66     return complete_size(ptr, adjustedSize);
67 }
68 
sk_allocate_throw(size_t size)69 SkSpan<std::byte> sk_allocate_throw(size_t size) {
70     if (size == 0) {
71         return {};
72     }
73     // Make sure to ask for at least the minimum number of bytes.
74     const size_t adjustedSize = std::max(size, kMinBytes);
75     void* ptr = sk_malloc_throw(adjustedSize);
76     return complete_size(ptr, adjustedSize);
77 }
78 
sk_report_container_overflow_and_die()79 void sk_report_container_overflow_and_die() {
80     SK_ABORT("Requested capacity is too large.");
81 }
82