OpenRCT2/src/openrct2/util/Util.cpp

895 lines
26 KiB
C++

/*****************************************************************************
* Copyright (c) 2014-2020 OpenRCT2 developers
*
* For a complete list of all authors, please refer to contributors.md
* Interested in contributing? Visit https://github.com/OpenRCT2/OpenRCT2
*
* OpenRCT2 is licensed under the GNU General Public License version 3.
*****************************************************************************/
#include "Util.h"
#include "../common.h"
#include "../core/Guard.hpp"
#include "../interface/Window.h"
#include "../localisation/Localisation.h"
#include "../platform/platform.h"
#include "../title/TitleScreen.h"
#include "zlib.h"
#include <algorithm>
#include <cctype>
#include <cmath>
#include <ctime>
#include <random>
int32_t squaredmetres_to_squaredfeet(int32_t squaredMetres)
{
// 1 metre squared = 10.7639104 feet squared
// RCT2 approximates as 11
return squaredMetres * 11;
}
int32_t metres_to_feet(int32_t metres)
{
// 1 metre = 3.2808399 feet
// RCT2 approximates as 3.28125
return (metres * 840) / 256;
}
int32_t mph_to_kmph(int32_t mph)
{
// 1 mph = 1.60934 kmph
// RCT2 approximates as 1.609375
return (mph * 1648) >> 10;
}
int32_t mph_to_dmps(int32_t mph)
{
// 1 mph = 4.4704 decimeters/s
return (mph * 73243) >> 14;
}
bool filename_valid_characters(const utf8* filename)
{
for (int32_t i = 0; filename[i] != '\0'; i++)
{
if (filename[i] == '\\' || filename[i] == '/' || filename[i] == ':' || filename[i] == '?' || filename[i] == '*'
|| filename[i] == '<' || filename[i] == '>' || filename[i] == '|')
return false;
}
return true;
}
utf8* path_get_directory(const utf8* path)
{
// Find the last slash or backslash in the path
char* filename = const_cast<char*>(strrchr(path, *PATH_SEPARATOR));
char* filename_posix = const_cast<char*>(strrchr(path, '/'));
filename = filename < filename_posix ? filename_posix : filename;
// If the path is invalid (e.g. just a file name), return NULL
if (filename == nullptr)
{
return nullptr;
}
char* directory = _strdup(path);
safe_strtrunc(directory, strlen(path) - strlen(filename) + 2);
return directory;
}
const char* path_get_filename(const utf8* path)
{
// Find last slash or backslash in the path
char* filename = const_cast<char*>(strrchr(path, *PATH_SEPARATOR));
char* filename_posix = const_cast<char*>(strchr(path, '/'));
filename = filename < filename_posix ? filename_posix : filename;
// Checks if the path is valid (e.g. not just a file name)
if (filename == nullptr)
{
// Return the input string to keep things working
return path;
}
// Increase pointer by one, to get rid of the slashes
filename++;
return filename;
}
// Returns the extension (dot inclusive) from the given path, or the end of the
// string when no extension was found.
const char* path_get_extension(const utf8* path)
{
// Get the filename from the path
const char* filename = path_get_filename(path);
// Try to find the most-right dot in the filename
char* extension = const_cast<char*>(strrchr(filename, '.'));
// When no dot was found, return a pointer to the null-terminator
if (extension == nullptr)
extension = const_cast<char*>(strrchr(filename, '\0'));
return extension;
}
void path_set_extension(utf8* path, const utf8* newExtension, size_t size)
{
// Remove existing extension (check first if there is one)
if (path_get_extension(path) < strrchr(path, '\0'))
path_remove_extension(path);
// Append new extension
path_append_extension(path, newExtension, size);
}
void path_append_extension(utf8* path, const utf8* newExtension, size_t size)
{
// Skip to the dot if the extension starts with a pattern (starts with "*.")
if (newExtension[0] == '*')
newExtension++;
// Append a dot to the filename if the new extension doesn't start with it
if (newExtension[0] != '.')
safe_strcat(path, ".", size);
// Append the extension to the path
safe_strcat(path, newExtension, size);
}
void path_remove_extension(utf8* path)
{
// Find last dot in filename, and replace it with a null-terminator
char* lastDot = const_cast<char*>(strrchr(path_get_filename(path), '.'));
if (lastDot != nullptr)
*lastDot = '\0';
else
log_warning("No extension found. (path = %s)", path);
}
void path_end_with_separator(utf8* path, size_t size)
{
size_t length = strnlen(path, size);
if (length >= size - 1)
return;
if ((length == 0) || ((path[length - 1] != *PATH_SEPARATOR) && path[length - 1] != '/'))
{
safe_strcat(path, PATH_SEPARATOR, size);
}
}
int32_t bitscanforward(int32_t source)
{
#if defined(_MSC_VER) && (_MSC_VER >= 1400) // Visual Studio 2005
DWORD i;
uint8_t success = _BitScanForward(&i, static_cast<uint32_t>(source));
return success != 0 ? i : -1;
#elif defined(__GNUC__)
int32_t success = __builtin_ffs(source);
return success - 1;
#else
# pragma message("Falling back to iterative bitscan forward, consider using intrinsics")
// This is a low-hanging optimisation boost, check if your compiler offers
// any intrinsic.
// cf. https://github.com/OpenRCT2/OpenRCT2/pull/2093
for (int32_t i = 0; i < 32; i++)
if (source & (1u << i))
return i;
return -1;
#endif
}
int32_t bitscanforward(int64_t source)
{
#if defined(_MSC_VER) && (_MSC_VER >= 1400) && defined(_M_X64) // Visual Studio 2005
DWORD i;
uint8_t success = _BitScanForward64(&i, static_cast<uint64_t>(source));
return success != 0 ? i : -1;
#elif defined(__GNUC__)
int32_t success = __builtin_ffsll(source);
return success - 1;
#else
# pragma message("Falling back to iterative bitscan forward, consider using intrinsics")
// This is a low-hanging optimisation boost, check if your compiler offers
// any intrinsic.
// cf. https://github.com/OpenRCT2/OpenRCT2/pull/2093
for (int32_t i = 0; i < 64; i++)
if (source & (1ull << i))
return i;
return -1;
#endif
}
#if defined(__GNUC__) && (defined(__x86_64__) || defined(__i386__))
# include <cpuid.h>
# define OpenRCT2_CPUID_GNUC_X86
#elif defined(_MSC_VER) && (_MSC_VER >= 1500) && (defined(_M_X64) || defined(_M_IX86)) // VS2008
# include <intrin.h>
# include <nmmintrin.h>
# define OpenRCT2_CPUID_MSVC_X86
#endif
#ifdef OPENRCT2_X86
static bool cpuid_x86(uint32_t* cpuid_outdata, int32_t eax)
{
# if defined(OpenRCT2_CPUID_GNUC_X86)
int ret = __get_cpuid(eax, &cpuid_outdata[0], &cpuid_outdata[1], &cpuid_outdata[2], &cpuid_outdata[3]);
return ret == 1;
# elif defined(OpenRCT2_CPUID_MSVC_X86)
__cpuid(reinterpret_cast<int*>(cpuid_outdata), static_cast<int>(eax));
return true;
# else
return false;
# endif
}
#endif // OPENRCT2_X86
bool sse41_available()
{
#ifdef OPENRCT2_X86
// SSE4.1 support is declared as the 19th bit of ECX with CPUID(EAX = 1).
uint32_t regs[4] = { 0 };
if (cpuid_x86(regs, 1))
{
return (regs[2] & (1 << 19));
}
#endif
return false;
}
bool avx2_available()
{
#ifdef OPENRCT2_X86
// For GCC and similar use the builtin function, as cpuid changed its semantics in
// https://github.com/gcc-mirror/gcc/commit/132fa33ce998df69a9f793d63785785f4b93e6f1
// which causes it to ignore subleafs, but the new function is unavailable on
// Ubuntu 18.04's toolchains.
# if defined(OpenRCT2_CPUID_GNUC_X86) && (!defined(__FreeBSD__) || (__FreeBSD__ > 10))
return __builtin_cpu_supports("avx2");
# else
// AVX2 support is declared as the 5th bit of EBX with CPUID(EAX = 7, ECX = 0).
uint32_t regs[4] = { 0 };
if (cpuid_x86(regs, 7))
{
bool avxCPUSupport = (regs[1] & (1 << 5)) != 0;
if (avxCPUSupport)
{
// Need to check if OS also supports the register of xmm/ymm
// This check has to be conditional, otherwise INVALID_INSTRUCTION exception.
uint64_t xcrFeatureMask = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
avxCPUSupport = (xcrFeatureMask & 0x6) || false;
}
return avxCPUSupport;
}
# endif
#endif
return false;
}
static bool bitcount_popcnt_available()
{
#ifdef OPENRCT2_X86
// POPCNT support is declared as the 23rd bit of ECX with CPUID(EAX = 1).
uint32_t regs[4] = { 0 };
if (cpuid_x86(regs, 1))
{
return (regs[2] & (1 << 23));
}
#endif
return false;
}
static int32_t bitcount_popcnt(uint32_t source)
{
// Use CPUID defines to figure out calling style
#if defined(OpenRCT2_CPUID_GNUC_X86)
// use asm directly in order to actually emit the instruction : using
// __builtin_popcount results in an extra call to a library function.
int32_t rv;
asm volatile("popcnt %1,%0" : "=r"(rv) : "rm"(source) : "cc");
return rv;
#elif defined(OpenRCT2_CPUID_MSVC_X86)
return _mm_popcnt_u32(source);
#else
openrct2_assert(false, "bitcount_popcnt() called, without support compiled in");
return INT_MAX;
#endif
}
static int32_t bitcount_lut(uint32_t source)
{
// https://graphics.stanford.edu/~seander/bithacks.html
static constexpr const uint8_t BitsSetTable256[256] = {
#define B2(n) n, (n) + 1, (n) + 1, (n) + 2
#define B4(n) B2(n), B2((n) + 1), B2((n) + 1), B2((n) + 2)
#define B6(n) B4(n), B4((n) + 1), B4((n) + 1), B4((n) + 2)
B6(0), B6(1), B6(1), B6(2)
};
return BitsSetTable256[source & 0xff] + BitsSetTable256[(source >> 8) & 0xff] + BitsSetTable256[(source >> 16) & 0xff]
+ BitsSetTable256[source >> 24];
}
static int32_t (*bitcount_fn)(uint32_t);
void bitcount_init()
{
bitcount_fn = bitcount_popcnt_available() ? bitcount_popcnt : bitcount_lut;
}
int32_t bitcount(uint32_t source)
{
return bitcount_fn(source);
}
/* case insensitive compare */
int32_t strcicmp(char const* a, char const* b)
{
for (;; a++, b++)
{
int32_t d = tolower(*a) - tolower(*b);
if (d != 0 || !*a)
return d;
}
}
/* Case insensitive logical compare */
// Example:
// - Guest 10
// - Guest 99
// - Guest 100
// - John v2.0
// - John v2.1
int32_t strlogicalcmp(const char* s1, const char* s2)
{
for (;;)
{
if (*s2 == '\0')
return *s1 != '\0';
if (*s1 == '\0')
return -1;
if (!(isdigit(*s1) && isdigit(*s2)))
{
if (toupper(*s1) != toupper(*s2))
return toupper(*s1) - toupper(*s2);
++s1;
++s2;
}
else
{
char *lim1, *lim2;
unsigned long n1 = strtoul(s1, &lim1, 10);
unsigned long n2 = strtoul(s2, &lim2, 10);
if (n1 > n2)
return 1;
if (n1 < n2)
return -1;
s1 = lim1;
s2 = lim2;
}
}
}
utf8* safe_strtrunc(utf8* text, size_t size)
{
assert(text != nullptr);
if (size == 0)
return text;
const char* sourceLimit = text + size - 1;
char* ch = text;
char* last = text;
while (utf8_get_next(ch, const_cast<const utf8**>(&ch)) != 0)
{
if (ch <= sourceLimit)
{
last = ch;
}
else
{
break;
}
}
*last = 0;
return text;
}
char* safe_strcpy(char* destination, const char* source, size_t size)
{
assert(destination != nullptr);
assert(source != nullptr);
if (size == 0)
return destination;
char* result = destination;
bool truncated = false;
const char* sourceLimit = source + size - 1;
const char* ch = source;
uint32_t codepoint;
while ((codepoint = utf8_get_next(ch, &ch)) != 0)
{
if (ch <= sourceLimit)
{
destination = utf8_write_codepoint(destination, codepoint);
}
else
{
truncated = true;
}
}
*destination = 0;
if (truncated)
{
log_warning("Truncating string \"%s\" to %d bytes.", result, size);
}
return result;
}
char* safe_strcat(char* destination, const char* source, size_t size)
{
assert(destination != nullptr);
assert(source != nullptr);
if (size == 0)
{
return destination;
}
char* result = destination;
size_t i;
for (i = 0; i < size; i++)
{
if (*destination == '\0')
{
break;
}
destination++;
}
bool terminated = false;
for (; i < size; i++)
{
if (*source != '\0')
{
*destination++ = *source++;
}
else
{
*destination = *source;
terminated = true;
break;
}
}
if (!terminated)
{
result[size - 1] = '\0';
log_warning("Truncating string \"%s\" to %d bytes.", result, size);
}
return result;
}
char* safe_strcat_path(char* destination, const char* source, size_t size)
{
path_end_with_separator(destination, size);
if (source[0] == *PATH_SEPARATOR)
{
source = source + 1;
}
return safe_strcat(destination, source, size);
}
#if defined(_WIN32)
char* strcasestr(const char* haystack, const char* needle)
{
const char* p1 = haystack;
const char* p2 = needle;
const char* r = *p2 == 0 ? haystack : nullptr;
while (*p1 != 0 && *p2 != 0)
{
if (tolower(static_cast<unsigned char>(*p1)) == tolower(static_cast<unsigned char>(*p2)))
{
if (r == nullptr)
r = p1;
p2++;
}
else
{
p2 = needle;
if (r != nullptr)
p1 = r + 1;
if (tolower(static_cast<unsigned char>(*p1)) == tolower(static_cast<unsigned char>(*p2)))
{
r = p1;
p2++;
}
else
{
r = nullptr;
}
}
p1++;
}
return *p2 == 0 ? const_cast<char*>(r) : nullptr;
}
#endif
bool utf8_is_bom(const char* str)
{
return str[0] == static_cast<char>(static_cast<uint8_t>(0xEF)) && str[1] == static_cast<char>(static_cast<uint8_t>(0xBB))
&& str[2] == static_cast<char>(static_cast<uint8_t>(0xBF));
}
bool str_is_null_or_empty(const char* str)
{
return str == nullptr || str[0] == 0;
}
uint32_t util_rand()
{
thread_local std::mt19937 _prng(std::random_device{}());
return _prng();
}
constexpr size_t CHUNK = 128 * 1024;
constexpr int32_t MAX_ZLIB_REALLOC = 4 * 1024 * 1024;
/**
* @brief Inflates zlib-compressed data
* @param data Data to be decompressed
* @param data_in_size Size of data to be decompressed
* @param data_out_size Pointer to a variable where output size will be written. If not 0, it will be used to set initial output
* buffer size.
* @return Returns a pointer to memory holding decompressed data or NULL on failure.
* @note It is caller's responsibility to free() the returned pointer once done with it.
*/
uint8_t* util_zlib_inflate(const uint8_t* data, size_t data_in_size, size_t* data_out_size)
{
int32_t ret = Z_OK;
uLongf out_size = static_cast<uLong>(*data_out_size);
if (out_size == 0)
{
// Try to guesstimate the size needed for output data by applying the
// same ratio it would take to compress data_in_size.
out_size = static_cast<uLong>(data_in_size) * static_cast<uLong>(data_in_size)
/ compressBound(static_cast<uLong>(data_in_size));
out_size = std::min(static_cast<uLongf>(MAX_ZLIB_REALLOC), out_size);
}
uLongf buffer_size = out_size;
uint8_t* buffer = static_cast<uint8_t*>(malloc(buffer_size));
do
{
if (ret == Z_BUF_ERROR)
{
buffer_size *= 2;
out_size = buffer_size;
buffer = static_cast<uint8_t*>(realloc(buffer, buffer_size));
}
else if (ret == Z_STREAM_ERROR)
{
log_error("Your build is shipped with broken zlib. Please use the official build.");
free(buffer);
return nullptr;
}
else if (ret < 0)
{
log_error("Error uncompressing data.");
free(buffer);
return nullptr;
}
ret = uncompress(buffer, &out_size, data, static_cast<uLong>(data_in_size));
} while (ret != Z_OK);
buffer = static_cast<uint8_t*>(realloc(buffer, out_size));
*data_out_size = out_size;
return buffer;
}
/**
* @brief Deflates input using zlib
* @param data Data to be compressed
* @param data_in_size Size of data to be compressed
* @return Returns an optional std::vector of bytes, which is equal to std::nullopt when deflate has failed
*/
std::optional<std::vector<uint8_t>> util_zlib_deflate(const uint8_t* data, size_t data_in_size)
{
int32_t ret = Z_OK;
uLongf out_size = 0;
uLong buffer_size = compressBound(static_cast<uLong>(data_in_size));
std::vector<uint8_t> buffer(buffer_size);
do
{
if (ret == Z_BUF_ERROR)
{
buffer_size *= 2;
out_size = buffer_size;
buffer.resize(buffer_size);
}
else if (ret == Z_STREAM_ERROR)
{
log_error("Your build is shipped with broken zlib. Please use the official build.");
return std::nullopt;
}
ret = compress(buffer.data(), &out_size, data, static_cast<uLong>(data_in_size));
} while (ret != Z_OK);
buffer.resize(out_size);
return buffer;
}
// Compress the source to gzip-compatible stream, write to dest.
// Mainly used for compressing the crashdumps
bool util_gzip_compress(FILE* source, FILE* dest)
{
if (source == nullptr || dest == nullptr)
{
return false;
}
int ret, flush;
size_t have;
z_stream strm{};
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
unsigned char in[CHUNK];
unsigned char out[CHUNK];
int windowBits = 15;
int GZIP_ENCODING = 16;
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, Z_DEFLATED, windowBits | GZIP_ENCODING, 8, Z_DEFAULT_STRATEGY);
if (ret != Z_OK)
{
log_error("Failed to initialise stream");
return false;
}
do
{
strm.avail_in = uInt(fread(in, 1, CHUNK, source));
if (ferror(source))
{
deflateEnd(&strm);
log_error("Failed to read data from source");
return false;
}
flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
strm.next_in = in;
do
{
strm.avail_out = CHUNK;
strm.next_out = out;
ret = deflate(&strm, flush);
if (ret == Z_STREAM_ERROR)
{
log_error("Failed to compress data");
return false;
}
have = CHUNK - strm.avail_out;
if (fwrite(out, 1, have, dest) != have || ferror(dest))
{
deflateEnd(&strm);
log_error("Failed to write data to destination");
return false;
}
} while (strm.avail_out == 0);
} while (flush != Z_FINISH);
deflateEnd(&strm);
return true;
}
std::vector<uint8_t> Gzip(const void* data, const size_t dataLen)
{
assert(data != nullptr);
std::vector<uint8_t> output;
z_stream strm{};
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
{
const auto ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 15 | 16, 8, Z_DEFAULT_STRATEGY);
if (ret != Z_OK)
{
throw std::runtime_error("deflateInit2 failed with error " + std::to_string(ret));
}
}
int flush = 0;
const auto* src = static_cast<const Bytef*>(data);
size_t srcRemaining = dataLen;
do
{
const auto nextBlockSize = std::min(srcRemaining, CHUNK);
srcRemaining -= nextBlockSize;
flush = srcRemaining == 0 ? Z_FINISH : Z_NO_FLUSH;
strm.avail_in = static_cast<uInt>(nextBlockSize);
strm.next_in = const_cast<Bytef*>(src);
do
{
output.resize(output.size() + nextBlockSize);
strm.avail_out = static_cast<uInt>(nextBlockSize);
strm.next_out = &output[output.size() - nextBlockSize];
const auto ret = deflate(&strm, flush);
if (ret == Z_STREAM_ERROR)
{
throw std::runtime_error("deflate failed with error " + std::to_string(ret));
}
output.resize(output.size() - strm.avail_out);
} while (strm.avail_out == 0);
src += nextBlockSize;
} while (flush != Z_FINISH);
deflateEnd(&strm);
return output;
}
std::vector<uint8_t> Ungzip(const void* data, const size_t dataLen)
{
assert(data != nullptr);
std::vector<uint8_t> output;
z_stream strm{};
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
{
const auto ret = inflateInit2(&strm, 15 | 16);
if (ret != Z_OK)
{
throw std::runtime_error("inflateInit2 failed with error " + std::to_string(ret));
}
}
int flush = 0;
const auto* src = static_cast<const Bytef*>(data);
size_t srcRemaining = dataLen;
do
{
const auto nextBlockSize = std::min(srcRemaining, CHUNK);
srcRemaining -= nextBlockSize;
flush = srcRemaining == 0 ? Z_FINISH : Z_NO_FLUSH;
strm.avail_in = static_cast<uInt>(nextBlockSize);
strm.next_in = const_cast<Bytef*>(src);
do
{
output.resize(output.size() + nextBlockSize);
strm.avail_out = static_cast<uInt>(nextBlockSize);
strm.next_out = &output[output.size() - nextBlockSize];
const auto ret = inflate(&strm, flush);
if (ret == Z_STREAM_ERROR)
{
throw std::runtime_error("deflate failed with error " + std::to_string(ret));
}
output.resize(output.size() - strm.avail_out);
} while (strm.avail_out == 0);
src += nextBlockSize;
} while (flush != Z_FINISH);
inflateEnd(&strm);
return output;
}
// Type-independent code left as macro to reduce duplicate code.
#define add_clamp_body(value, value_to_add, min_cap, max_cap) \
if ((value_to_add > 0) && (value > (max_cap - (value_to_add)))) \
{ \
value = max_cap; \
} \
else if ((value_to_add < 0) && (value < (min_cap - (value_to_add)))) \
{ \
value = min_cap; \
} \
else \
{ \
value += value_to_add; \
}
int8_t add_clamp_int8_t(int8_t value, int8_t value_to_add)
{
add_clamp_body(value, value_to_add, INT8_MIN, INT8_MAX);
return value;
}
int16_t add_clamp_int16_t(int16_t value, int16_t value_to_add)
{
add_clamp_body(value, value_to_add, INT16_MIN, INT16_MAX);
return value;
}
int32_t add_clamp_int32_t(int32_t value, int32_t value_to_add)
{
add_clamp_body(value, value_to_add, INT32_MIN, INT32_MAX);
return value;
}
int64_t add_clamp_int64_t(int64_t value, int64_t value_to_add)
{
add_clamp_body(value, value_to_add, INT64_MIN, INT64_MAX);
return value;
}
money32 add_clamp_money32(money32 value, money32 value_to_add)
{
// This function is intended only for clarity, as money32
// is technically the same as int32_t
assert_struct_size(money32, sizeof(int32_t));
return add_clamp_int32_t(value, value_to_add);
}
money32 add_clamp_money64(money64 value, money64 value_to_add)
{
// This function is intended only for clarity, as money64
// is technically the same as int64_t
assert_struct_size(money64, sizeof(int64_t));
return add_clamp_int64_t(value, value_to_add);
}
#undef add_clamp_body
uint8_t lerp(uint8_t a, uint8_t b, float t)
{
if (t <= 0)
return a;
if (t >= 1)
return b;
int32_t range = b - a;
int32_t amount = static_cast<int32_t>(range * t);
return static_cast<uint8_t>(a + amount);
}
float flerp(float a, float b, float f)
{
return (a * (1.0f - f)) + (b * f);
}
uint8_t soft_light(uint8_t a, uint8_t b)
{
float fa = a / 255.0f;
float fb = b / 255.0f;
float fr;
if (fb < 0.5f)
{
fr = (2 * fa * fb) + ((fa * fa) * (1 - (2 * fb)));
}
else
{
fr = (2 * fa * (1 - fb)) + (std::sqrt(fa) * ((2 * fb) - 1));
}
return static_cast<uint8_t>(std::clamp(fr, 0.0f, 1.0f) * 255.0f);
}
/**
* strftime wrapper which appends to an existing string.
*/
size_t strcatftime(char* buffer, size_t bufferSize, const char* format, const struct tm* tp)
{
size_t stringLen = strnlen(buffer, bufferSize);
if (stringLen < bufferSize)
{
char* dst = buffer + stringLen;
size_t dstMaxSize = bufferSize - stringLen;
return strftime(dst, dstMaxSize, format, tp);
}
return 0;
}