test/test_buffer.cpp

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
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 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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#include "cx/buffer.h"

#include <gtest/gtest.h>
#include "util_allocator.h"

TEST(BufferInit, WrapSpace) {
    CxTestingAllocator alloc;
    CxBuffer buf;
    void *space = cxMalloc(&alloc, 16);
    cxBufferInit(&buf, space, 16, &alloc, CX_BUFFER_DEFAULT);
    EXPECT_EQ(buf.space, space);
    EXPECT_EQ(buf.flags & CX_BUFFER_AUTO_EXTEND, 0);
    EXPECT_EQ(buf.flags & CX_BUFFER_FREE_CONTENTS, 0);
    EXPECT_EQ(buf.pos, 0);
    EXPECT_EQ(buf.size, 0);
    EXPECT_EQ(buf.capacity, 16);
    EXPECT_EQ(buf.allocator, &alloc);
    cxBufferDestroy(&buf);
    EXPECT_FALSE(alloc.verify());
    cxFree(&alloc, space);
    EXPECT_TRUE(alloc.verify());
}

TEST(BufferInit, WrapSpaceAutoFree) {
    CxTestingAllocator alloc;
    CxBuffer buf;
    void *space = cxMalloc(&alloc, 16);
    cxBufferInit(&buf, space, 16, &alloc, CX_BUFFER_FREE_CONTENTS);
    EXPECT_EQ(buf.space, space);
    EXPECT_EQ(buf.flags & CX_BUFFER_AUTO_EXTEND, 0);
    EXPECT_EQ(buf.flags & CX_BUFFER_FREE_CONTENTS, CX_BUFFER_FREE_CONTENTS);
    EXPECT_EQ(buf.pos, 0);
    EXPECT_EQ(buf.size, 0);
    EXPECT_EQ(buf.capacity, 16);
    EXPECT_EQ(buf.allocator, &alloc);
    EXPECT_FALSE(alloc.verify());
    cxBufferDestroy(&buf);
    EXPECT_TRUE(alloc.verify());
}

TEST(BufferInit, FreshSpace) {
    CxTestingAllocator alloc;
    CxBuffer buf;
    cxBufferInit(&buf, nullptr, 8, &alloc, CX_BUFFER_DEFAULT);
    EXPECT_NE(buf.space, nullptr);
    EXPECT_EQ(buf.flags & CX_BUFFER_AUTO_EXTEND, 0);
    EXPECT_EQ(buf.flags & CX_BUFFER_FREE_CONTENTS, CX_BUFFER_FREE_CONTENTS);
    EXPECT_EQ(buf.pos, 0);
    EXPECT_EQ(buf.size, 0);
    EXPECT_EQ(buf.capacity, 8);
    EXPECT_EQ(buf.allocator, &alloc);
    EXPECT_FALSE(alloc.verify()); // space is still allocated
    cxBufferDestroy(&buf);
    EXPECT_TRUE(alloc.verify());
}

class BufferShiftFixture : public ::testing::Test {
protected:
    void SetUp() override {
        ASSERT_TRUE(alloc.verify());
        cxBufferInit(&buf, nullptr, 16, &alloc, CX_BUFFER_DEFAULT);
        memcpy(buf.space, "test____________", 16);
        buf.capacity = 8; // purposely pretend that the buffer has less capacity s.t. we can test beyond the range
        buf.pos = 4;
        buf.size = 4;
    }

    void TearDown() override {
        cxBufferDestroy(&buf);
        EXPECT_TRUE(alloc.verify());
    }

    CxTestingAllocator alloc;
    CxBuffer buf{};
};

class BufferShiftLeft : public BufferShiftFixture {
};

TEST_F(BufferShiftLeft, Zero) {
    ASSERT_EQ(buf.pos, 4);
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShiftLeft(&buf, 0);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 4);
    EXPECT_EQ(buf.size, 4);
    EXPECT_TRUE(memcmp(buf.space, "test________", 8) == 0);
}

TEST_F(BufferShiftLeft, Standard) {
    ASSERT_EQ(buf.pos, 4);
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShiftLeft(&buf, 2);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 2);
    EXPECT_EQ(buf.size, 2);
    EXPECT_TRUE(memcmp(buf.space, "stst________", 8) == 0);
}

TEST_F(BufferShiftLeft, Overshift) {
    ASSERT_LT(buf.pos, 6);
    ASSERT_LT(buf.size, 6);
    int ret = cxBufferShiftLeft(&buf, 6);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 0);
    EXPECT_EQ(buf.size, 0);
    EXPECT_TRUE(memcmp(buf.space, "test________", 8) == 0);
}

TEST_F(BufferShiftLeft, OvershiftPosOnly) {
    buf.pos = 2;
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShiftLeft(&buf, 3);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 0);
    EXPECT_EQ(buf.size, 1);
    EXPECT_TRUE(memcmp(buf.space, "test________", 8) == 0);
}

TEST_F(BufferShiftLeft, OffsetInterface) {
    buf.pos = 3;
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShift(&buf, -2);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 1);
    EXPECT_EQ(buf.size, 2);
    EXPECT_TRUE(memcmp(buf.space, "stst________", 8) == 0);
}

class BufferShiftRight : public BufferShiftFixture {
};

TEST_F(BufferShiftRight, Zero) {
    ASSERT_EQ(buf.pos, 4);
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShiftRight(&buf, 0);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 4);
    EXPECT_EQ(buf.size, 4);
    EXPECT_TRUE(memcmp(buf.space, "test________", 8) == 0);
}

TEST_F(BufferShiftRight, Standard) {
    ASSERT_EQ(buf.pos, 4);
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShiftRight(&buf, 3);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 7);
    EXPECT_EQ(buf.size, 7);
    EXPECT_TRUE(memcmp(buf.space, "testest_____", 8) == 0);
}

TEST_F(BufferShiftRight, OvershiftDiscard) {
    ASSERT_EQ(buf.pos, 4);
    ASSERT_EQ(buf.size, 4);
    ASSERT_EQ(buf.capacity, 8);
    int ret = cxBufferShiftRight(&buf, 6);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 8);
    EXPECT_EQ(buf.size, 8);
    EXPECT_EQ(buf.capacity, 8);
    EXPECT_TRUE(memcmp(buf.space, "test__te____", 8) == 0);
}

TEST_F(BufferShiftRight, OvershiftExtend) {
    ASSERT_EQ(buf.pos, 4);
    ASSERT_EQ(buf.size, 4);
    ASSERT_EQ(buf.capacity, 8);
    buf.flags |= CX_BUFFER_AUTO_EXTEND;
    int ret = cxBufferShiftRight(&buf, 6);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 10);
    EXPECT_EQ(buf.size, 10);
    EXPECT_GE(buf.capacity, 10);
    EXPECT_TRUE(memcmp(buf.space, "test__test__", 8) == 0);
}

TEST_F(BufferShiftRight, OffsetInterface) {
    buf.pos = 3;
    ASSERT_EQ(buf.size, 4);
    int ret = cxBufferShift(&buf, 2);
    EXPECT_EQ(ret, 0);
    EXPECT_EQ(buf.pos, 5);
    EXPECT_EQ(buf.size, 6);
    EXPECT_TRUE(memcmp(buf.space, "tetest______", 8) == 0);
}

TEST(BufferMinimumCapacity, Sufficient) {
    CxTestingAllocator alloc;
    auto space = cxMalloc(&alloc, 8);
    CxBuffer buf;
    cxBufferInit(&buf, space, 8, &alloc, CX_BUFFER_FREE_CONTENTS);
    memcpy(space, "Testing", 8);
    buf.size = 8;
    cxBufferMinimumCapacity(&buf, 6);
    EXPECT_EQ(buf.capacity, 8);
    EXPECT_EQ(buf.size, 8);
    EXPECT_TRUE(memcmp(buf.space, "Testing", 8) == 0);
    cxBufferDestroy(&buf);
    EXPECT_TRUE(alloc.verify());
}

TEST(BufferMinimumCapacity, Extend) {
    CxTestingAllocator alloc;
    auto space = cxMalloc(&alloc, 8);
    CxBuffer buf;
    cxBufferInit(&buf, space, 8, &alloc, CX_BUFFER_FREE_CONTENTS); // NO auto extend!
    memcpy(space, "Testing", 8);
    buf.size = 8;
    cxBufferMinimumCapacity(&buf, 16);
    EXPECT_EQ(buf.capacity, 16);
    EXPECT_EQ(buf.size, 8);
    EXPECT_TRUE(memcmp(buf.space, "Testing", 8) == 0);
    cxBufferDestroy(&buf);
    EXPECT_TRUE(alloc.verify());
}

TEST(BufferClear, Test) {
    char space[16];
    strcpy(space, "clear test");
    CxBuffer buf;
    cxBufferInit(&buf, space, 16, cxDefaultAllocator, CX_BUFFER_DEFAULT);
    ASSERT_EQ(buf.size, 0);
    // only clear the used part of the buffer
    cxBufferClear(&buf);
    EXPECT_EQ(memcmp(space, "clear test", 10), 0);
    buf.size = 5;
    buf.pos = 3;
    cxBufferClear(&buf);
    EXPECT_EQ(memcmp(space, "\0\0\0\0\0 test", 10), 0);
    EXPECT_EQ(buf.size, 0);
    EXPECT_EQ(buf.pos, 0);
}