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1 /*
2  * Copyright 2019-2021 Hans-Kristian Arntzen
3  * SPDX-License-Identifier: Apache-2.0 OR MIT
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 /*
19  * At your option, you may choose to accept this material under either:
20  *  1. The Apache License, Version 2.0, found at <http://www.apache.org/licenses/LICENSE-2.0>, or
21  *  2. The MIT License, found at <http://opensource.org/licenses/MIT>.
22  */
23 
24 #ifndef SPIRV_CROSS_CONTAINERS_HPP
25 #define SPIRV_CROSS_CONTAINERS_HPP
26 
27 #include "spirv_cross_error_handling.hpp"
28 #include <algorithm>
29 #include <functional>
30 #include <iterator>
31 #include <limits>
32 #include <memory>
33 #include <stack>
34 #include <stddef.h>
35 #include <stdint.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <type_traits>
39 #include <unordered_map>
40 #include <unordered_set>
41 #include <utility>
42 #include <vector>
43 
44 #ifdef SPIRV_CROSS_NAMESPACE_OVERRIDE
45 #define SPIRV_CROSS_NAMESPACE SPIRV_CROSS_NAMESPACE_OVERRIDE
46 #else
47 #define SPIRV_CROSS_NAMESPACE spirv_cross
48 #endif
49 
50 namespace SPIRV_CROSS_NAMESPACE
51 {
52 #ifndef SPIRV_CROSS_FORCE_STL_TYPES
53 // std::aligned_storage does not support size == 0, so roll our own.
54 template <typename T, size_t N>
55 class AlignedBuffer
56 {
57 public:
data()58 	T *data()
59 	{
60 #if defined(_MSC_VER) && _MSC_VER < 1900
61 		// MSVC 2013 workarounds, sigh ...
62 		// Only use this workaround on MSVC 2013 due to some confusion around default initialized unions.
63 		// Spec seems to suggest the memory will be zero-initialized, which is *not* what we want.
64 		return reinterpret_cast<T *>(u.aligned_char);
65 #else
66 		return reinterpret_cast<T *>(aligned_char);
67 #endif
68 	}
69 
70 private:
71 #if defined(_MSC_VER) && _MSC_VER < 1900
72 	// MSVC 2013 workarounds, sigh ...
73 	union
74 	{
75 		char aligned_char[sizeof(T) * N];
76 		double dummy_aligner;
77 	} u;
78 #else
79 	alignas(T) char aligned_char[sizeof(T) * N];
80 #endif
81 };
82 
83 template <typename T>
84 class AlignedBuffer<T, 0>
85 {
86 public:
data()87 	T *data()
88 	{
89 		return nullptr;
90 	}
91 };
92 
93 // An immutable version of SmallVector which erases type information about storage.
94 template <typename T>
95 class VectorView
96 {
97 public:
operator [](size_t i)98 	T &operator[](size_t i) SPIRV_CROSS_NOEXCEPT
99 	{
100 		return ptr[i];
101 	}
102 
operator [](size_t i) const103 	const T &operator[](size_t i) const SPIRV_CROSS_NOEXCEPT
104 	{
105 		return ptr[i];
106 	}
107 
empty() const108 	bool empty() const SPIRV_CROSS_NOEXCEPT
109 	{
110 		return buffer_size == 0;
111 	}
112 
size() const113 	size_t size() const SPIRV_CROSS_NOEXCEPT
114 	{
115 		return buffer_size;
116 	}
117 
data()118 	T *data() SPIRV_CROSS_NOEXCEPT
119 	{
120 		return ptr;
121 	}
122 
data() const123 	const T *data() const SPIRV_CROSS_NOEXCEPT
124 	{
125 		return ptr;
126 	}
127 
begin()128 	T *begin() SPIRV_CROSS_NOEXCEPT
129 	{
130 		return ptr;
131 	}
132 
end()133 	T *end() SPIRV_CROSS_NOEXCEPT
134 	{
135 		return ptr + buffer_size;
136 	}
137 
begin() const138 	const T *begin() const SPIRV_CROSS_NOEXCEPT
139 	{
140 		return ptr;
141 	}
142 
end() const143 	const T *end() const SPIRV_CROSS_NOEXCEPT
144 	{
145 		return ptr + buffer_size;
146 	}
147 
front()148 	T &front() SPIRV_CROSS_NOEXCEPT
149 	{
150 		return ptr[0];
151 	}
152 
front() const153 	const T &front() const SPIRV_CROSS_NOEXCEPT
154 	{
155 		return ptr[0];
156 	}
157 
back()158 	T &back() SPIRV_CROSS_NOEXCEPT
159 	{
160 		return ptr[buffer_size - 1];
161 	}
162 
back() const163 	const T &back() const SPIRV_CROSS_NOEXCEPT
164 	{
165 		return ptr[buffer_size - 1];
166 	}
167 
168 	// Makes it easier to consume SmallVector.
169 #if defined(_MSC_VER) && _MSC_VER < 1900
operator std::vector<T>() const170 	explicit operator std::vector<T>() const
171 	{
172 		// Another MSVC 2013 workaround. It does not understand lvalue/rvalue qualified operations.
173 		return std::vector<T>(ptr, ptr + buffer_size);
174 	}
175 #else
176 	// Makes it easier to consume SmallVector.
operator std::vector<T>() const177 	explicit operator std::vector<T>() const &
178 	{
179 		return std::vector<T>(ptr, ptr + buffer_size);
180 	}
181 
182 	// If we are converting as an r-value, we can pilfer our elements.
operator std::vector<T>()183 	explicit operator std::vector<T>() &&
184 	{
185 		return std::vector<T>(std::make_move_iterator(ptr), std::make_move_iterator(ptr + buffer_size));
186 	}
187 #endif
188 
189 	// Avoid sliced copies. Base class should only be read as a reference.
190 	VectorView(const VectorView &) = delete;
191 	void operator=(const VectorView &) = delete;
192 
193 protected:
194 	VectorView() = default;
195 	T *ptr = nullptr;
196 	size_t buffer_size = 0;
197 };
198 
199 // Simple vector which supports up to N elements inline, without malloc/free.
200 // We use a lot of throwaway vectors all over the place which triggers allocations.
201 // This class only implements the subset of std::vector we need in SPIRV-Cross.
202 // It is *NOT* a drop-in replacement in general projects.
203 template <typename T, size_t N = 8>
204 class SmallVector : public VectorView<T>
205 {
206 public:
SmallVector()207 	SmallVector() SPIRV_CROSS_NOEXCEPT
208 	{
209 		this->ptr = stack_storage.data();
210 		buffer_capacity = N;
211 	}
212 
SmallVector(const T * arg_list_begin,const T * arg_list_end)213 	SmallVector(const T *arg_list_begin, const T *arg_list_end) SPIRV_CROSS_NOEXCEPT : SmallVector()
214 	{
215 		auto count = size_t(arg_list_end - arg_list_begin);
216 		reserve(count);
217 		for (size_t i = 0; i < count; i++, arg_list_begin++)
218 			new (&this->ptr[i]) T(*arg_list_begin);
219 		this->buffer_size = count;
220 	}
221 
SmallVector(std::initializer_list<T> init)222 	SmallVector(std::initializer_list<T> init) SPIRV_CROSS_NOEXCEPT : SmallVector(init.begin(), init.end())
223 	{
224 	}
225 
SmallVector(SmallVector && other)226 	SmallVector(SmallVector &&other) SPIRV_CROSS_NOEXCEPT : SmallVector()
227 	{
228 		*this = std::move(other);
229 	}
230 
operator =(SmallVector && other)231 	SmallVector &operator=(SmallVector &&other) SPIRV_CROSS_NOEXCEPT
232 	{
233 		clear();
234 		if (other.ptr != other.stack_storage.data())
235 		{
236 			// Pilfer allocated pointer.
237 			if (this->ptr != stack_storage.data())
238 				free(this->ptr);
239 			this->ptr = other.ptr;
240 			this->buffer_size = other.buffer_size;
241 			buffer_capacity = other.buffer_capacity;
242 			other.ptr = nullptr;
243 			other.buffer_size = 0;
244 			other.buffer_capacity = 0;
245 		}
246 		else
247 		{
248 			// Need to move the stack contents individually.
249 			reserve(other.buffer_size);
250 			for (size_t i = 0; i < other.buffer_size; i++)
251 			{
252 				new (&this->ptr[i]) T(std::move(other.ptr[i]));
253 				other.ptr[i].~T();
254 			}
255 			this->buffer_size = other.buffer_size;
256 			other.buffer_size = 0;
257 		}
258 		return *this;
259 	}
260 
SmallVector(const SmallVector & other)261 	SmallVector(const SmallVector &other) SPIRV_CROSS_NOEXCEPT : SmallVector()
262 	{
263 		*this = other;
264 	}
265 
operator =(const SmallVector & other)266 	SmallVector &operator=(const SmallVector &other) SPIRV_CROSS_NOEXCEPT
267 	{
268 		if (this == &other)
269 			return *this;
270 
271 		clear();
272 		reserve(other.buffer_size);
273 		for (size_t i = 0; i < other.buffer_size; i++)
274 			new (&this->ptr[i]) T(other.ptr[i]);
275 		this->buffer_size = other.buffer_size;
276 		return *this;
277 	}
278 
SmallVector(size_t count)279 	explicit SmallVector(size_t count) SPIRV_CROSS_NOEXCEPT : SmallVector()
280 	{
281 		resize(count);
282 	}
283 
~SmallVector()284 	~SmallVector()
285 	{
286 		clear();
287 		if (this->ptr != stack_storage.data())
288 			free(this->ptr);
289 	}
290 
clear()291 	void clear() SPIRV_CROSS_NOEXCEPT
292 	{
293 		for (size_t i = 0; i < this->buffer_size; i++)
294 			this->ptr[i].~T();
295 		this->buffer_size = 0;
296 	}
297 
push_back(const T & t)298 	void push_back(const T &t) SPIRV_CROSS_NOEXCEPT
299 	{
300 		reserve(this->buffer_size + 1);
301 		new (&this->ptr[this->buffer_size]) T(t);
302 		this->buffer_size++;
303 	}
304 
push_back(T && t)305 	void push_back(T &&t) SPIRV_CROSS_NOEXCEPT
306 	{
307 		reserve(this->buffer_size + 1);
308 		new (&this->ptr[this->buffer_size]) T(std::move(t));
309 		this->buffer_size++;
310 	}
311 
pop_back()312 	void pop_back() SPIRV_CROSS_NOEXCEPT
313 	{
314 		// Work around false positive warning on GCC 8.3.
315 		// Calling pop_back on empty vector is undefined.
316 		if (!this->empty())
317 			resize(this->buffer_size - 1);
318 	}
319 
320 	template <typename... Ts>
emplace_back(Ts &&...ts)321 	void emplace_back(Ts &&... ts) SPIRV_CROSS_NOEXCEPT
322 	{
323 		reserve(this->buffer_size + 1);
324 		new (&this->ptr[this->buffer_size]) T(std::forward<Ts>(ts)...);
325 		this->buffer_size++;
326 	}
327 
reserve(size_t count)328 	void reserve(size_t count) SPIRV_CROSS_NOEXCEPT
329 	{
330 		if ((count > std::numeric_limits<size_t>::max() / sizeof(T)) ||
331 		    (count > std::numeric_limits<size_t>::max() / 2))
332 		{
333 			// Only way this should ever happen is with garbage input, terminate.
334 			std::terminate();
335 		}
336 
337 		if (count > buffer_capacity)
338 		{
339 			size_t target_capacity = buffer_capacity;
340 			if (target_capacity == 0)
341 				target_capacity = 1;
342 
343 			// Weird parens works around macro issues on Windows if NOMINMAX is not used.
344 			target_capacity = (std::max)(target_capacity, N);
345 
346 			// Need to ensure there is a POT value of target capacity which is larger than count,
347 			// otherwise this will overflow.
348 			while (target_capacity < count)
349 				target_capacity <<= 1u;
350 
351 			T *new_buffer =
352 			    target_capacity > N ? static_cast<T *>(malloc(target_capacity * sizeof(T))) : stack_storage.data();
353 
354 			// If we actually fail this malloc, we are hosed anyways, there is no reason to attempt recovery.
355 			if (!new_buffer)
356 				std::terminate();
357 
358 			// In case for some reason two allocations both come from same stack.
359 			if (new_buffer != this->ptr)
360 			{
361 				// We don't deal with types which can throw in move constructor.
362 				for (size_t i = 0; i < this->buffer_size; i++)
363 				{
364 					new (&new_buffer[i]) T(std::move(this->ptr[i]));
365 					this->ptr[i].~T();
366 				}
367 			}
368 
369 			if (this->ptr != stack_storage.data())
370 				free(this->ptr);
371 			this->ptr = new_buffer;
372 			buffer_capacity = target_capacity;
373 		}
374 	}
375 
insert(T * itr,const T * insert_begin,const T * insert_end)376 	void insert(T *itr, const T *insert_begin, const T *insert_end) SPIRV_CROSS_NOEXCEPT
377 	{
378 		auto count = size_t(insert_end - insert_begin);
379 		if (itr == this->end())
380 		{
381 			reserve(this->buffer_size + count);
382 			for (size_t i = 0; i < count; i++, insert_begin++)
383 				new (&this->ptr[this->buffer_size + i]) T(*insert_begin);
384 			this->buffer_size += count;
385 		}
386 		else
387 		{
388 			if (this->buffer_size + count > buffer_capacity)
389 			{
390 				auto target_capacity = this->buffer_size + count;
391 				if (target_capacity == 0)
392 					target_capacity = 1;
393 				if (target_capacity < N)
394 					target_capacity = N;
395 
396 				while (target_capacity < count)
397 					target_capacity <<= 1u;
398 
399 				// Need to allocate new buffer. Move everything to a new buffer.
400 				T *new_buffer =
401 				    target_capacity > N ? static_cast<T *>(malloc(target_capacity * sizeof(T))) : stack_storage.data();
402 
403 				// If we actually fail this malloc, we are hosed anyways, there is no reason to attempt recovery.
404 				if (!new_buffer)
405 					std::terminate();
406 
407 				// First, move elements from source buffer to new buffer.
408 				// We don't deal with types which can throw in move constructor.
409 				auto *target_itr = new_buffer;
410 				auto *original_source_itr = this->begin();
411 
412 				if (new_buffer != this->ptr)
413 				{
414 					while (original_source_itr != itr)
415 					{
416 						new (target_itr) T(std::move(*original_source_itr));
417 						original_source_itr->~T();
418 						++original_source_itr;
419 						++target_itr;
420 					}
421 				}
422 
423 				// Copy-construct new elements.
424 				for (auto *source_itr = insert_begin; source_itr != insert_end; ++source_itr, ++target_itr)
425 					new (target_itr) T(*source_itr);
426 
427 				// Move over the other half.
428 				if (new_buffer != this->ptr || insert_begin != insert_end)
429 				{
430 					while (original_source_itr != this->end())
431 					{
432 						new (target_itr) T(std::move(*original_source_itr));
433 						original_source_itr->~T();
434 						++original_source_itr;
435 						++target_itr;
436 					}
437 				}
438 
439 				if (this->ptr != stack_storage.data())
440 					free(this->ptr);
441 				this->ptr = new_buffer;
442 				buffer_capacity = target_capacity;
443 			}
444 			else
445 			{
446 				// Move in place, need to be a bit careful about which elements are constructed and which are not.
447 				// Move the end and construct the new elements.
448 				auto *target_itr = this->end() + count;
449 				auto *source_itr = this->end();
450 				while (target_itr != this->end() && source_itr != itr)
451 				{
452 					--target_itr;
453 					--source_itr;
454 					new (target_itr) T(std::move(*source_itr));
455 				}
456 
457 				// For already constructed elements we can move-assign.
458 				std::move_backward(itr, source_itr, target_itr);
459 
460 				// For the inserts which go to already constructed elements, we can do a plain copy.
461 				while (itr != this->end() && insert_begin != insert_end)
462 					*itr++ = *insert_begin++;
463 
464 				// For inserts into newly allocated memory, we must copy-construct instead.
465 				while (insert_begin != insert_end)
466 				{
467 					new (itr) T(*insert_begin);
468 					++itr;
469 					++insert_begin;
470 				}
471 			}
472 
473 			this->buffer_size += count;
474 		}
475 	}
476 
insert(T * itr,const T & value)477 	void insert(T *itr, const T &value) SPIRV_CROSS_NOEXCEPT
478 	{
479 		insert(itr, &value, &value + 1);
480 	}
481 
erase(T * itr)482 	T *erase(T *itr) SPIRV_CROSS_NOEXCEPT
483 	{
484 		std::move(itr + 1, this->end(), itr);
485 		this->ptr[--this->buffer_size].~T();
486 		return itr;
487 	}
488 
erase(T * start_erase,T * end_erase)489 	void erase(T *start_erase, T *end_erase) SPIRV_CROSS_NOEXCEPT
490 	{
491 		if (end_erase == this->end())
492 		{
493 			resize(size_t(start_erase - this->begin()));
494 		}
495 		else
496 		{
497 			auto new_size = this->buffer_size - (end_erase - start_erase);
498 			std::move(end_erase, this->end(), start_erase);
499 			resize(new_size);
500 		}
501 	}
502 
resize(size_t new_size)503 	void resize(size_t new_size) SPIRV_CROSS_NOEXCEPT
504 	{
505 		if (new_size < this->buffer_size)
506 		{
507 			for (size_t i = new_size; i < this->buffer_size; i++)
508 				this->ptr[i].~T();
509 		}
510 		else if (new_size > this->buffer_size)
511 		{
512 			reserve(new_size);
513 			for (size_t i = this->buffer_size; i < new_size; i++)
514 				new (&this->ptr[i]) T();
515 		}
516 
517 		this->buffer_size = new_size;
518 	}
519 
520 private:
521 	size_t buffer_capacity = 0;
522 	AlignedBuffer<T, N> stack_storage;
523 };
524 
525 // A vector without stack storage.
526 // Could also be a typedef-ed to std::vector,
527 // but might as well use the one we have.
528 template <typename T>
529 using Vector = SmallVector<T, 0>;
530 
531 #else // SPIRV_CROSS_FORCE_STL_TYPES
532 
533 template <typename T, size_t N = 8>
534 using SmallVector = std::vector<T>;
535 template <typename T>
536 using Vector = std::vector<T>;
537 template <typename T>
538 using VectorView = std::vector<T>;
539 
540 #endif // SPIRV_CROSS_FORCE_STL_TYPES
541 
542 // An object pool which we use for allocating IVariant-derived objects.
543 // We know we are going to allocate a bunch of objects of each type,
544 // so amortize the mallocs.
545 class ObjectPoolBase
546 {
547 public:
548 	virtual ~ObjectPoolBase() = default;
549 	virtual void free_opaque(void *ptr) = 0;
550 };
551 
552 template <typename T>
553 class ObjectPool : public ObjectPoolBase
554 {
555 public:
ObjectPool(unsigned start_object_count_=16)556 	explicit ObjectPool(unsigned start_object_count_ = 16)
557 	    : start_object_count(start_object_count_)
558 	{
559 	}
560 
561 	template <typename... P>
allocate(P &&...p)562 	T *allocate(P &&... p)
563 	{
564 		if (vacants.empty())
565 		{
566 			unsigned num_objects = start_object_count << memory.size();
567 			T *ptr = static_cast<T *>(malloc(num_objects * sizeof(T)));
568 			if (!ptr)
569 				return nullptr;
570 
571 			for (unsigned i = 0; i < num_objects; i++)
572 				vacants.push_back(&ptr[i]);
573 
574 			memory.emplace_back(ptr);
575 		}
576 
577 		T *ptr = vacants.back();
578 		vacants.pop_back();
579 		new (ptr) T(std::forward<P>(p)...);
580 		return ptr;
581 	}
582 
free(T * ptr)583 	void free(T *ptr)
584 	{
585 		ptr->~T();
586 		vacants.push_back(ptr);
587 	}
588 
free_opaque(void * ptr)589 	void free_opaque(void *ptr) override
590 	{
591 		free(static_cast<T *>(ptr));
592 	}
593 
clear()594 	void clear()
595 	{
596 		vacants.clear();
597 		memory.clear();
598 	}
599 
600 protected:
601 	Vector<T *> vacants;
602 
603 	struct MallocDeleter
604 	{
operator ()SPIRV_CROSS_NAMESPACE::ObjectPool::MallocDeleter605 		void operator()(T *ptr)
606 		{
607 			::free(ptr);
608 		}
609 	};
610 
611 	SmallVector<std::unique_ptr<T, MallocDeleter>> memory;
612 	unsigned start_object_count;
613 };
614 
615 template <size_t StackSize = 4096, size_t BlockSize = 4096>
616 class StringStream
617 {
618 public:
StringStream()619 	StringStream()
620 	{
621 		reset();
622 	}
623 
~StringStream()624 	~StringStream()
625 	{
626 		reset();
627 	}
628 
629 	// Disable copies and moves. Makes it easier to implement, and we don't need it.
630 	StringStream(const StringStream &) = delete;
631 	void operator=(const StringStream &) = delete;
632 
633 	template <typename T, typename std::enable_if<!std::is_floating_point<T>::value, int>::type = 0>
operator <<(const T & t)634 	StringStream &operator<<(const T &t)
635 	{
636 		auto s = std::to_string(t);
637 		append(s.data(), s.size());
638 		return *this;
639 	}
640 
641 	// Only overload this to make float/double conversions ambiguous.
operator <<(uint32_t v)642 	StringStream &operator<<(uint32_t v)
643 	{
644 		auto s = std::to_string(v);
645 		append(s.data(), s.size());
646 		return *this;
647 	}
648 
operator <<(char c)649 	StringStream &operator<<(char c)
650 	{
651 		append(&c, 1);
652 		return *this;
653 	}
654 
operator <<(const std::string & s)655 	StringStream &operator<<(const std::string &s)
656 	{
657 		append(s.data(), s.size());
658 		return *this;
659 	}
660 
operator <<(const char * s)661 	StringStream &operator<<(const char *s)
662 	{
663 		append(s, strlen(s));
664 		return *this;
665 	}
666 
667 	template <size_t N>
operator <<(const char (& s)[N])668 	StringStream &operator<<(const char (&s)[N])
669 	{
670 		append(s, strlen(s));
671 		return *this;
672 	}
673 
str() const674 	std::string str() const
675 	{
676 		std::string ret;
677 		size_t target_size = 0;
678 		for (auto &saved : saved_buffers)
679 			target_size += saved.offset;
680 		target_size += current_buffer.offset;
681 		ret.reserve(target_size);
682 
683 		for (auto &saved : saved_buffers)
684 			ret.insert(ret.end(), saved.buffer, saved.buffer + saved.offset);
685 		ret.insert(ret.end(), current_buffer.buffer, current_buffer.buffer + current_buffer.offset);
686 		return ret;
687 	}
688 
reset()689 	void reset()
690 	{
691 		for (auto &saved : saved_buffers)
692 			if (saved.buffer != stack_buffer)
693 				free(saved.buffer);
694 		if (current_buffer.buffer != stack_buffer)
695 			free(current_buffer.buffer);
696 
697 		saved_buffers.clear();
698 		current_buffer.buffer = stack_buffer;
699 		current_buffer.offset = 0;
700 		current_buffer.size = sizeof(stack_buffer);
701 	}
702 
703 private:
704 	struct Buffer
705 	{
706 		char *buffer = nullptr;
707 		size_t offset = 0;
708 		size_t size = 0;
709 	};
710 	Buffer current_buffer;
711 	char stack_buffer[StackSize];
712 	SmallVector<Buffer> saved_buffers;
713 
append(const char * s,size_t len)714 	void append(const char *s, size_t len)
715 	{
716 		size_t avail = current_buffer.size - current_buffer.offset;
717 		if (avail < len)
718 		{
719 			if (avail > 0)
720 			{
721 				memcpy(current_buffer.buffer + current_buffer.offset, s, avail);
722 				s += avail;
723 				len -= avail;
724 				current_buffer.offset += avail;
725 			}
726 
727 			saved_buffers.push_back(current_buffer);
728 			size_t target_size = len > BlockSize ? len : BlockSize;
729 			current_buffer.buffer = static_cast<char *>(malloc(target_size));
730 			if (!current_buffer.buffer)
731 				SPIRV_CROSS_THROW("Out of memory.");
732 
733 			memcpy(current_buffer.buffer, s, len);
734 			current_buffer.offset = len;
735 			current_buffer.size = target_size;
736 		}
737 		else
738 		{
739 			memcpy(current_buffer.buffer + current_buffer.offset, s, len);
740 			current_buffer.offset += len;
741 		}
742 	}
743 };
744 
745 } // namespace SPIRV_CROSS_NAMESPACE
746 
747 #endif
748