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#include "memstack.h"
#include "test.h"
#define NUM_INTS 10
#define CAPACITY (NUM_INTS * sizeof(int))
// Create and destroy a statically-backed stack.
TEST_CASE(memstack_create) {
int memory[CAPACITY];
memstack stack = {0};
memstack_make(&stack, CAPACITY, memory);
memstack_del(&stack);
}
// Create and destroy a dynamically-backed stack.
TEST_CASE(mem_create_dyn) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
memstack_del(&stack);
}
// Allocate all N ints.
TEST_CASE(memstack_allocate_until_full) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
for (int i = 0; i < NUM_INTS; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
}
TEST_TRUE(memstack_size(&stack) == CAPACITY);
memstack_del(&stack);
}
// Allocate all N ints, then free them.
TEST_CASE(memstack_fill_then_free) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
int* blocks[NUM_INTS] = {nullptr};
for (int i = 0; i < NUM_INTS; ++i) {
blocks[i] = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(blocks[i] != nullptr);
}
memstack_clear(&stack);
TEST_EQUAL(memstack_size(&stack), 0);
memstack_del(&stack);
}
// Attempt to allocate blocks past the maximum stack size.
// The stack should handle the failed allocations gracefully.
TEST_CASE(memstack_allocate_beyond_max_size) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
memstack_enable_traps(&stack, false);
// Fully allocate the stack.
for (int i = 0; i < NUM_INTS; ++i) {
TEST_TRUE(memstack_alloc(&stack, sizeof(int)) != nullptr);
}
// Past the end.
for (int i = 0; i < NUM_INTS; ++i) {
TEST_EQUAL(memstack_alloc(&stack, sizeof(int)), nullptr);
}
TEST_TRUE(memstack_size(&stack) == CAPACITY);
memstack_del(&stack);
}
// Free blocks should always remain zeroed out.
// This tests the invariant right after creating the stack.
TEST_CASE(memstack_zero_free_blocks_after_creation) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
for (int i = 0; i < NUM_INTS; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
TEST_EQUAL(*block, 0);
}
memstack_del(&stack);
}
// Free blocks should always remain zeroed out.
// This tests the invariant after clearing the stack and allocating a new block.
TEST_CASE(memstack_zero_free_block_after_free) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
for (int i = 0; i < NUM_INTS; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
TEST_EQUAL(*block, 0);
}
memstack_clear(&stack);
for (int i = 0; i < NUM_INTS; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
TEST_EQUAL(*block, 0);
}
memstack_del(&stack);
}
// Aligned allocations should be properly aligned.
TEST_CASE(memstack_alloc_aligned) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
// -1 because the base address of the memory storage might be unaligned.
for (int i = 0; i < NUM_INTS - 1; ++i) {
const int* block =
memstack_alloc_aligned(&stack, sizeof(int), alignof(int));
TEST_TRUE(block != nullptr);
TEST_EQUAL(*block, 0);
TEST_EQUAL((uintptr_t)block % alignof(int), 0);
}
memstack_del(&stack);
}
// Get and set the watermark.
TEST_CASE(memstack_watermark) {
memstack stack = {0};
memstack_make(&stack, CAPACITY, nullptr);
// Allocate N/2 ints.
for (int i = 0; i < NUM_INTS / 2; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
}
const size_t watermark = memstack_watermark(&stack);
// Allocate the remaining N/2 ints.
for (int i = 0; i < NUM_INTS / 2; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
}
// Now reset the watermark halfway through.
memstack_set_watermark(&stack, watermark);
// Allocate the remaining N/2 ints (again).
for (int i = 0; i < NUM_INTS / 2; ++i) {
const int* block = memstack_alloc(&stack, sizeof(int));
TEST_TRUE(block != nullptr);
}
memstack_del(&stack);
}
int main() { return 0; }
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