ObjFW  Check-in [a7ebc72ac7]

	return _atEndOfStream;
}

- (size_t)lowlevelReadIntoBuffer: (void*)buffer
			  length: (size_t)length
{
	ssize_t ret;


	if (_fd == -1 || _atEndOfStream)
		@throw [OFReadFailedException exceptionWithObject: self
						  requestedLength: length];

#ifndef _WIN32
	if ((ret = read(_fd, buffer, length)) < 0)

 * `NSLibraryDirectory` directory.@n
 * On Windows, it uses the `APPDATA` environment variable.@n
 * On Haiku, it uses the `B_USER_SETTINGS_DIRECTORY` directory.
 *
 * @return The path where user configuration for the application can be stored
 */
+ (OFString*)userConfigPath;

/*!
 * @brief Returns the vendor of the CPU.
 *
 * If the vendor could not be determined, nil is returned instead.
 *
 * @return The vendor of the CPU
 */
+ (OFString*)CPUVendor;

/*!
 * @brief Returns whether the CPU supports MMX.
 *
 * @return Whether the CPU supports MMX
 */
+ (bool)supportsMMX;

/*!
 * @brief Returns whether the CPU supports SSE.
 *
 * @return Whether the CPU supports SSE
 */
+ (bool)supportsSSE;

/*!
 * @brief Returns whether the CPU supports SSE2.
 *
 * @return Whether the CPU supports SSE2
 */
+ (bool)supportsSSE2;

/*!
 * @brief Returns whether the CPU supports SSE3.
 *
 * @return Whether the CPU supports SSE3
 */
+ (bool)supportsSSE3;

/*!
 * @brief Returns whether the CPU supports SSSE3.
 *
 * @return Whether the CPU supports SSSE3
 */
+ (bool)supportsSSSE3;

/*!
 * @brief Returns whether the CPU supports SSE4.1.
 *
 * @return Whether the CPU supports SSE4.1
 */
+ (bool)supportsSSE41;

/*!
 * @brief Returns whether the CPU supports SSE4.2.
 *
 * @return Whether the CPU supports SSE4.2
 */
+ (bool)supportsSSE42;

/*!
 * @brief Returns whether the CPU supports AVX.
 *
 * @return Whether the CPU supports AVX
 */
+ (bool)supportsAVX;

/*!
 * @brief Returns whether the CPU supports AVX2.
 *
 * @return Whether the CPU supports AVX2
 */
+ (bool)supportsAVX2;
@end

#endif
#ifdef __HAIKU__
# include <FindDirectory.h>
#endif
#ifdef __QNX__
# include <sys/syspage.h>
#endif

struct cpuid_regs {
	uint32_t eax, ebx, ecx, edx;
};

static size_t pageSize;
static size_t numberOfCPUs;

static OF_INLINE struct cpuid_regs OF_CONST_FUNC
cpuid(uint32_t eax, uint32_t ecx)
{
	struct cpuid_regs regs;

#if defined(OF_X86_64_ASM) || defined(OF_X86_ASM)
	__asm__(
	    "cpuid"
	    : "=a"(regs.eax), "=b"(regs.ebx), "=c"(regs.ecx), "=d"(regs.edx)
	    : "a"(eax), "c"(ecx)
	);
#else
	regs.eax = regs.ebx = regs.ecx = regs.edx = 0;
#endif

	return regs;
}

@implementation OFSystemInfo
+ (void)initialize
{
	if (self != [OFSystemInfo class])
		return;

	var = [var stringByAppendingPathComponent: @".config"];

	[var retain];
	objc_autoreleasePoolPop(pool);
	return [var autorelease];
#endif
}

+ (OFString*)CPUVendor
{
	struct cpuid_regs regs = cpuid(0, 0);
	char buffer[12];

	if (regs.eax == 0)
		return nil;

	memcpy(buffer, &regs.ebx, 4);
	memcpy(buffer + 4, &regs.edx, 4);
	memcpy(buffer + 8, &regs.ecx, 4);

	return [OFString stringWithCString: buffer
				  encoding: OF_STRING_ENCODING_ASCII
				    length: 12];
}

+ (bool)supportsMMX
{
	return (cpuid(1, 0).edx & (1 << 23));
}

+ (bool)supportsSSE
{
	return (cpuid(1, 0).edx & (1 << 25));
}

+ (bool)supportsSSE2
{
	return (cpuid(1, 0).edx & (1 << 26));
}

+ (bool)supportsSSE3
{
	return (cpuid(1, 0).ecx & (1 << 0));
}

+ (bool)supportsSSSE3
{
	return (cpuid(1, 0).ecx & (1 << 9));
}

+ (bool)supportsSSE41
{
	return (cpuid(1, 0).ecx & (1 << 19));
}

+ (bool)supportsSSE42
{
	return (cpuid(1, 0).ecx & (1 << 20));
}

+ (bool)supportsAVX
{
	return (cpuid(1, 0).ecx & (1 << 28));
}

+ (bool)supportsAVX2
{
	return cpuid(0, 0).eax >= 7 && (cpuid(7, 0).ebx & (1 << 5));
}
@end