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/*
* smslib.m
*
* SMSLib Sudden Motion Sensor Access Library
* Copyright (c) 2010 Suitable Systems
* All rights reserved.
*
* Developed by: Daniel Griscom
* Suitable Systems
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal with the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimers.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimers in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the names of Suitable Systems nor the names of its
* contributors may be used to endorse or promote products derived from
* this Software without specific prior written permission.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE SOFTWARE.
*
* For more information about SMSLib, see
* or contact
* Daniel Griscom
* Suitable Systems
* 1 Centre Street, Suite 204
* Wakefield, MA 01880
* (781) 665-0053
*
*/
#import <IOKit/IOKitLib.h>
#import <sys/sysctl.h>
#import <math.h>
#import "smslib.h"
#pragma mark Internal structures
// Represents a single axis of a type of sensor.
typedef struct axisStruct {
int enabled; // Non-zero if axis is valid in this sensor
int index; // Location in struct of first byte
int size; // Number of bytes
float zerog; // Value meaning "zero g"
float oneg; // Change in value meaning "increase of one g"
// (can be negative if axis sensor reversed)
} axisStruct;
// Represents the configuration of a type of sensor.
typedef struct sensorSpec {
const char* model; // Prefix of model to be tested
const char* name; // Name of device to be read
unsigned int function; // Kernel function index
int recordSize; // Size of record to be sent/received
axisStruct axes[3]; // Description of three axes (X, Y, Z)
} sensorSpec;
// Configuration of all known types of sensors. The configurations are
// tried in order until one succeeds in returning data.
// All default values are set here, but each axis' zerog and oneg values
// may be changed to saved (calibrated) values.
//
// These values came from SeisMaCalibrate calibration reports. In general I've
// found the following:
// - All Intel-based SMSs have 250 counts per g, centered on 0, but the signs
// are different (and in one case two axes are swapped)
// - PowerBooks and iBooks all have sensors centered on 0, and reading 50-53
// steps per gravity (but with differing polarities!)
// - PowerBooks and iBooks of the same model all have the same axis polarities
// - PowerBook and iBook access methods are model- and OS version-specific
//
// So, the sequence of tests is:
// - Try model-specific access methods. Note that the test is for a match to the
// beginning of the model name, e.g. the record with model name "MacBook"
// matches computer models "MacBookPro1,2" and "MacBook1,1" (and "" matches
// any model).
// - If no model-specific record's access fails, then try each model-independent
// method in order, stopping when one works.
static const sensorSpec sensors[] = {
// ****** Model-dependent methods ******
// The PowerBook5,6 is one of the G4 models that seems to lose
// SMS access until the next reboot.
{"PowerBook5,6",
"IOI2CMotionSensor",
21,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, -51.5}, {1, 2, 1, 0, -51.5}}},
// The PowerBook5,7 is one of the G4 models that seems to lose
// SMS access until the next reboot.
{"PowerBook5,7",
"IOI2CMotionSensor",
21,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, 51.5}, {1, 2, 1, 0, 51.5}}},
// Access seems to be reliable on the PowerBook5,8
{"PowerBook5,8",
"PMUMotionSensor",
21,
60,
{{1, 0, 1, 0, -51.5}, {1, 1, 1, 0, 51.5}, {1, 2, 1, 0, -51.5}}},
// Access seems to be reliable on the PowerBook5,9
{"PowerBook5,9",
"PMUMotionSensor",
21,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, -51.5}, {1, 2, 1, 0, -51.5}}},
// The PowerBook6,7 is one of the G4 models that seems to lose
// SMS access until the next reboot.
{"PowerBook6,7",
"IOI2CMotionSensor",
21,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, 51.5}, {1, 2, 1, 0, 51.5}}},
// The PowerBook6,8 is one of the G4 models that seems to lose
// SMS access until the next reboot.
{"PowerBook6,8",
"IOI2CMotionSensor",
21,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, 51.5}, {1, 2, 1, 0, 51.5}}},
// MacBook Pro Core 2 Duo 17". Note the reversed Y and Z axes.
{"MacBookPro2,1",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, 251}, {1, 2, 2, 0, -251}, {1, 4, 2, 0, -251}}},
// MacBook Pro Core 2 Duo 15" AND 17" with LED backlight, introduced June
// '07.
// NOTE! The 17" machines have the signs of their X and Y axes reversed
// from this calibration, but there's no clear way to discriminate between
// the two machines.
{"MacBookPro3,1",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, -251}, {1, 2, 2, 0, 251}, {1, 4, 2, 0, -251}}},
// ... specs?
{"MacBook5,2",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, -251}, {1, 2, 2, 0, 251}, {1, 4, 2, 0, -251}}},
// ... specs?
{"MacBookPro5,1",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, -251}, {1, 2, 2, 0, -251}, {1, 4, 2, 0, 251}}},
// ... specs?
{"MacBookPro5,2",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, -251}, {1, 2, 2, 0, -251}, {1, 4, 2, 0, 251}}},
// This is speculative, based on a single user's report. Looks like the X
// and Y axes
// are swapped. This is true for no other known Appple laptop.
{"MacBookPro5,3",
"SMCMotionSensor",
5,
40,
{{1, 2, 2, 0, -251}, {1, 0, 2, 0, -251}, {1, 4, 2, 0, -251}}},
// ... specs?
{"MacBookPro5,4",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, -251}, {1, 2, 2, 0, -251}, {1, 4, 2, 0, 251}}},
// ****** Model-independent methods ******
// Seen once with PowerBook6,8 under system 10.3.9; I suspect
// other G4-based 10.3.* systems might use this
{"",
"IOI2CMotionSensor",
24,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, 51.5}, {1, 2, 1, 0, 51.5}}},
// PowerBook5,6 , PowerBook5,7 , PowerBook6,7 , PowerBook6,8
// under OS X 10.4.*
{"",
"IOI2CMotionSensor",
21,
60,
{{1, 0, 1, 0, 51.5}, {1, 1, 1, 0, 51.5}, {1, 2, 1, 0, 51.5}}},
// PowerBook5,8 , PowerBook5,9 under OS X 10.4.*
{"",
"PMUMotionSensor",
21,
60,
{// Each has two out of three gains negative, but it's different
// for the different models. So, this will be right in two out
// of three axis for either model.
{1, 0, 1, 0, -51.5},
{1, 1, 1, -6, -51.5},
{1, 2, 1, 0, -51.5}}},
// All MacBook, MacBookPro models. Hardware (at least on early MacBookPro
// 15")
// is Kionix KXM52-1050 three-axis accelerometer chip. Data is at
// models
// that use this are:
// MacBook1,1
// MacBook2,1
// MacBook3,1
// MacBook4,1
// MacBook5,1
// MacBook6,1
// MacBookAir1,1
// MacBookPro1,1
// MacBookPro1,2
// MacBookPro4,1
// MacBookPro5,5
{"",
"SMCMotionSensor",
5,
40,
{{1, 0, 2, 0, 251}, {1, 2, 2, 0, 251}, {1, 4, 2, 0, 251}}}};
#define SENSOR_COUNT (sizeof(sensors) / sizeof(sensorSpec))
#pragma mark Internal prototypes
static int getData(sms_acceleration* accel, int calibrated, id logObject,
SEL logSelector);
static float getAxis(int which, int calibrated);
static int signExtend(int value, int size);
static NSString* getModelName(void);
static NSString* getOSVersion(void);
static BOOL loadCalibration(void);
static void storeCalibration(void);
static void defaultCalibration(void);
static void deleteCalibration(void);
static int prefIntRead(NSString* prefName, BOOL* success);
static void prefIntWrite(NSString* prefName, int prefValue);
static float prefFloatRead(NSString* prefName, BOOL* success);
static void prefFloatWrite(NSString* prefName, float prefValue);
static void prefDelete(NSString* prefName);
static void prefSynchronize(void);
// static long getMicroseconds(void);
float fakeData(NSTimeInterval time);
#pragma mark Static variables
static int debugging = NO; // True if debugging (synthetic data)
static io_connect_t connection; // Connection for reading accel values
static int running = NO; // True if we successfully started
static unsigned int sensorNum = 0; // The current index into sensors[]
static const char* serviceName; // The name of the current service
static char *iRecord, *oRecord; // Pointers to read/write records for sensor
static int recordSize; // Size of read/write records
static unsigned int function; // Which kernel function should be used
static float zeros[3]; // X, Y and Z zero calibration values
static float onegs[3]; // X, Y and Z one-g calibration values
#pragma mark Defines
// Pattern for building axis letter from axis number
#define INT_TO_AXIS(a) (a == 0 ? @"X" : a == 1 ? @"Y" : @"Z")
// Name of configuration for given axis' zero (axis specified by integer)
#define ZERO_NAME(a) [NSString stringWithFormat:@"%@-Axis-Zero", INT_TO_AXIS(a)]
// Name of configuration for given axis' oneg (axis specified by integer)
#define ONEG_NAME(a) \
[NSString stringWithFormat:@"%@-Axis-One-g", INT_TO_AXIS(a)]
// Name of "Is calibrated" preference
#define CALIBRATED_NAME (@"Calibrated")
// Application domain for SeisMac library
#define APP_ID ((CFStringRef) @"com.suitable.SeisMacLib")
// These #defines make the accelStartup code a LOT easier to read.
#undef LOG
#define LOG(message) \
if (logObject) { \
[logObject performSelector:logSelector withObject:message]; \
}
#define LOG_ARG(format, var1) \
if (logObject) { \
[logObject performSelector:logSelector \
withObject:[NSString stringWithFormat:format, var1]]; \
}
#define LOG_2ARG(format, var1, var2) \
if (logObject) { \
[logObject \
performSelector:logSelector \
withObject:[NSString stringWithFormat:format, var1, var2]]; \
}
#define LOG_3ARG(format, var1, var2, var3) \
if (logObject) { \
[logObject \
performSelector:logSelector \
withObject:[NSString stringWithFormat:format, var1, var2, var3]]; \
}
#pragma mark Function definitions
// This starts up the accelerometer code, trying each possible sensor
// specification. Note that for logging purposes it
// takes an object and a selector; the object's selector is then invoked
// with a single NSString as argument giving progress messages. Example
// logging method:
// - (void)logMessage: (NSString *)theString
// which would be used in accelStartup's invocation thusly:
// result = accelStartup(self, @selector(logMessage:));
// If the object is nil, then no logging is done. Sets calibation from built-in
// value table. Returns ACCEL_SUCCESS for success, and other (negative)
// values for various failures (returns value indicating result of
// most successful trial).
int smsStartup(id logObject, SEL logSelector) {
io_iterator_t iterator;
io_object_t device;
kern_return_t result;
sms_acceleration accel;
int failure_result = SMS_FAIL_MODEL;
running = NO;
debugging = NO;
NSString* modelName = getModelName();
LOG_ARG(@"Machine model: %@\n", modelName);
LOG_ARG(@"OS X version: %@\n", getOSVersion());
LOG_ARG(@"Accelerometer library version: %s\n", SMSLIB_VERSION);
for (sensorNum = 0; sensorNum < SENSOR_COUNT; sensorNum++) {
// Set up all specs for this type of sensor
serviceName = sensors[sensorNum].name;
recordSize = sensors[sensorNum].recordSize;
function = sensors[sensorNum].function;
LOG_3ARG(@"Trying service \"%s\" with selector %d and %d byte record:\n",
serviceName, function, recordSize);
NSString* targetName =
[NSString stringWithCString:sensors[sensorNum].model
encoding:NSMacOSRomanStringEncoding];
LOG_ARG(@" Comparing model name to target \"%@\": ", targetName);
if ([targetName length] == 0 || [modelName hasPrefix:targetName]) {
LOG(@"success.\n");
} else {
LOG(@"failure.\n");
// Don't need to increment failure_result.
continue;
}
LOG(@" Fetching dictionary for service: ");
CFMutableDictionaryRef dict = IOServiceMatching(serviceName);
if (dict) {
LOG(@"success.\n");
} else {
LOG(@"failure.\n");
if (failure_result < SMS_FAIL_DICTIONARY) {
failure_result = SMS_FAIL_DICTIONARY;
}
continue;
}
LOG(@" Getting list of matching services: ");
result =
IOServiceGetMatchingServices(kIOMasterPortDefault, dict, &iterator);
if (result == KERN_SUCCESS) {
LOG(@"success.\n");
} else {
LOG_ARG(@"failure, with return value 0x%x.\n", result);
if (failure_result < SMS_FAIL_LIST_SERVICES) {
failure_result = SMS_FAIL_LIST_SERVICES;
}
continue;
}
LOG(@" Getting first device in list: ");
device = IOIteratorNext(iterator);
if (device == 0) {
LOG(@"failure.\n");
if (failure_result < SMS_FAIL_NO_SERVICES) {
failure_result = SMS_FAIL_NO_SERVICES;
}
continue;
} else {
LOG(@"success.\n");
LOG(@" Opening device: ");
}
result = IOServiceOpen(device, mach_task_self(), 0, &connection);
if (result != KERN_SUCCESS) {
LOG_ARG(@"failure, with return value 0x%x.\n", result);
IOObjectRelease(device);
if (failure_result < SMS_FAIL_OPENING) {
failure_result = SMS_FAIL_OPENING;
}
continue;
} else if (connection == 0) {
LOG_ARG(
@"'success', but didn't get a connection (return value was: 0x%x).\n",
result);
IOObjectRelease(device);
if (failure_result < SMS_FAIL_CONNECTION) {
failure_result = SMS_FAIL_CONNECTION;
}
continue;
} else {
IOObjectRelease(device);
LOG(@"success.\n");
}
LOG(@" Testing device.\n");
defaultCalibration();
iRecord = (char*)malloc(recordSize);
oRecord = (char*)malloc(recordSize);
running = YES;
result = getData(&accel, true, logObject, logSelector);
running = NO;
if (result) {
LOG_ARG(@" Failure testing device, with result 0x%x.\n", result);
free(iRecord);
iRecord = 0;
free(oRecord);
oRecord = 0;
if (failure_result < SMS_FAIL_ACCESS) {
failure_result = SMS_FAIL_ACCESS;
}
continue;
} else {
LOG(@" Success testing device!\n");
running = YES;
return SMS_SUCCESS;
}
}
return failure_result;
}
// This starts up the library in debug mode, ignoring the actual hardware.
// Returned data is in the form of 1Hz sine waves, with the X, Y and Z
// axes 120 degrees out of phase; "calibrated" data has range +/- (1.0/5);
// "uncalibrated" data has range +/- (256/5). X and Y axes centered on 0.0,
// Z axes centered on 1 (calibrated) or 256 (uncalibrated).
// Don't use smsGetBufferLength or smsGetBufferData. Always returns SMS_SUCCESS.
int smsDebugStartup(id logObject, SEL logSelector) {
LOG(@"Starting up in debug mode\n");
debugging = YES;
return SMS_SUCCESS;
}
// Returns the current calibration values.
void smsGetCalibration(sms_calibration* calibrationRecord) {
int x;
for (x = 0; x < 3; x++) {
calibrationRecord->zeros[x] = (debugging ? 0 : zeros[x]);
calibrationRecord->onegs[x] = (debugging ? 256 : onegs[x]);
}
}
// Sets the calibration, but does NOT store it as a preference. If the argument
// is nil then the current calibration is set from the built-in value table.
void smsSetCalibration(sms_calibration* calibrationRecord) {
int x;
if (!debugging) {
if (calibrationRecord) {
for (x = 0; x < 3; x++) {
zeros[x] = calibrationRecord->zeros[x];
onegs[x] = calibrationRecord->onegs[x];
}
} else {
defaultCalibration();
}
}
}
// Stores the current calibration values as a stored preference.
void smsStoreCalibration(void) {
if (!debugging) storeCalibration();
}
// Loads the stored preference values into the current calibration.
// Returns YES if successful.
BOOL smsLoadCalibration(void) {
if (debugging) {
return YES;
} else if (loadCalibration()) {
return YES;
} else {
defaultCalibration();
return NO;
}
}
// Deletes any stored calibration, and then takes the current calibration values
// from the built-in value table.
void smsDeleteCalibration(void) {
if (!debugging) {
deleteCalibration();
defaultCalibration();
}
}
// Fills in the accel record with calibrated acceleration data. Takes
// 1-2ms to return a value. Returns 0 if success, error number if failure.
int smsGetData(sms_acceleration* accel) {
NSTimeInterval time;
if (debugging) {
usleep(1500); // Usually takes 1-2 milliseconds
time = [NSDate timeIntervalSinceReferenceDate];
accel->x = fakeData(time) / 5;
accel->y = fakeData(time - 1) / 5;
accel->z = fakeData(time - 2) / 5 + 1.0;
return true;
} else {
return getData(accel, true, nil, nil);
}
}
// Fills in the accel record with uncalibrated acceleration data.
// Returns 0 if success, error number if failure.
int smsGetUncalibratedData(sms_acceleration* accel) {
NSTimeInterval time;
if (debugging) {
usleep(1500); // Usually takes 1-2 milliseconds
time = [NSDate timeIntervalSinceReferenceDate];
accel->x = fakeData(time) * 256 / 5;
accel->y = fakeData(time - 1) * 256 / 5;
accel->z = fakeData(time - 2) * 256 / 5 + 256;
return true;
} else {
return getData(accel, false, nil, nil);
}
}
// Returns the length of a raw block of data for the current type of sensor.
int smsGetBufferLength(void) {
if (debugging) {
return 0;
} else if (running) {
return sensors[sensorNum].recordSize;
} else {
return 0;
}
}
// Takes a pointer to accelGetRawLength() bytes; sets those bytes
// to return value from sensor. Make darn sure the buffer length is right!
void smsGetBufferData(char* buffer) {
IOItemCount iSize = recordSize;
IOByteCount oSize = recordSize;
kern_return_t result;
if (debugging || running == NO) {
return;
}
memset(iRecord, 1, iSize);
memset(buffer, 0, oSize);
#if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1050
const size_t InStructSize = recordSize;
size_t OutStructSize = recordSize;
result = IOConnectCallStructMethod(connection,
function, // magic kernel function number
(const void*)iRecord, InStructSize,
(void*)buffer, &OutStructSize);
#else // __MAC_OS_X_VERSION_MIN_REQUIRED 1050
result = IOConnectMethodStructureIStructureO(
connection,
function, // magic kernel function number
iSize, &oSize, iRecord, buffer);
#endif // __MAC_OS_X_VERSION_MIN_REQUIRED 1050
if (result != KERN_SUCCESS) {
running = NO;
}
}
// This returns an NSString describing the current calibration in
// human-readable form. Also include a description of the machine.
NSString* smsGetCalibrationDescription(void) {
BOOL success;
NSMutableString* s = [[NSMutableString alloc] init];
if (debugging) {
[s release];
return @"Debugging!";
}
[s appendString:@"---- SeisMac Calibration Record ----\n \n"];
[s appendFormat:@"Machine model: %@\n", getModelName()];
[s appendFormat:@"OS X build: %@\n", getOSVersion()];
[s appendFormat:@"SeisMacLib version %s, record %d\n \n", SMSLIB_VERSION,
sensorNum];
[s appendFormat:@"Using service \"%s\", function index %d, size %d\n \n",
serviceName, function, recordSize];
if (prefIntRead(CALIBRATED_NAME, &success) && success) {
[s appendString:@"Calibration values (from calibration):\n"];
} else {
[s appendString:@"Calibration values (from defaults):\n"];
}
[s appendFormat:@" X-Axis-Zero = %.2f\n", zeros[0]];
[s appendFormat:@" X-Axis-One-g = %.2f\n", onegs[0]];
[s appendFormat:@" Y-Axis-Zero = %.2f\n", zeros[1]];
[s appendFormat:@" Y-Axis-One-g = %.2f\n", onegs[1]];
[s appendFormat:@" Z-Axis-Zero = %.2f\n", zeros[2]];
[s appendFormat:@" Z-Axis-One-g = %.2f\n \n", onegs[2]];
[s appendString:@"---- End Record ----\n"];
return s;
}
// Shuts down the accelerometer.
void smsShutdown(void) {
if (!debugging) {
running = NO;
if (iRecord) free(iRecord);
if (oRecord) free(oRecord);
IOServiceClose(connection);
}
}
#pragma mark Internal functions
// Loads the current calibration from the stored preferences.
// Returns true iff successful.
BOOL loadCalibration(void) {
BOOL thisSuccess, allSuccess;
int x;
prefSynchronize();
if (prefIntRead(CALIBRATED_NAME, &thisSuccess) && thisSuccess) {
// Calibrated. Set all values from saved values.
allSuccess = YES;
for (x = 0; x < 3; x++) {
zeros[x] = prefFloatRead(ZERO_NAME(x), &thisSuccess);
allSuccess &= thisSuccess;
onegs[x] = prefFloatRead(ONEG_NAME(x), &thisSuccess);
allSuccess &= thisSuccess;
}
return allSuccess;
}
return NO;
}
// Stores the current calibration into the stored preferences.
static void storeCalibration(void) {
int x;
prefIntWrite(CALIBRATED_NAME, 1);
for (x = 0; x < 3; x++) {
prefFloatWrite(ZERO_NAME(x), zeros[x]);
prefFloatWrite(ONEG_NAME(x), onegs[x]);
}
prefSynchronize();
}
// Sets the calibration to its default values.
void defaultCalibration(void) {
int x;
for (x = 0; x < 3; x++) {
zeros[x] = sensors[sensorNum].axes[x].zerog;
onegs[x] = sensors[sensorNum].axes[x].oneg;
}
}
// Deletes the stored preferences.
static void deleteCalibration(void) {
int x;
prefDelete(CALIBRATED_NAME);
for (x = 0; x < 3; x++) {
prefDelete(ZERO_NAME(x));
prefDelete(ONEG_NAME(x));
}
prefSynchronize();
}
// Read a named floating point value from the stored preferences. Sets
// the success boolean based on, you guessed it, whether it succeeds.
static float prefFloatRead(NSString* prefName, BOOL* success) {
float result = 0.0f;
CFPropertyListRef ref =
CFPreferencesCopyAppValue((CFStringRef)prefName, APP_ID);
// If there isn't such a preference, fail
if (ref == NULL) {
*success = NO;
return result;
}
CFTypeID typeID = CFGetTypeID(ref);
// Is it a number?
if (typeID == CFNumberGetTypeID()) {
// Is it a floating point number?
if (CFNumberIsFloatType((CFNumberRef)ref)) {
// Yup: grab it.
*success =
CFNumberGetValue((__CFNumber*)ref, kCFNumberFloat32Type, &result);
} else {
// Nope: grab as an integer, and convert to a float.
long num;
if (CFNumberGetValue((CFNumberRef)ref, kCFNumberLongType, &num)) {
result = num;
*success = YES;
} else {
*success = NO;
}
}
// Or is it a string (e.g. set by the command line "defaults" command)?
} else if (typeID == CFStringGetTypeID()) {
result = (float)CFStringGetDoubleValue((CFStringRef)ref);
*success = YES;
} else {
// Can't convert to a number: fail.
*success = NO;
}
CFRelease(ref);
return result;
}
// Writes a named floating point value to the stored preferences.
static void prefFloatWrite(NSString* prefName, float prefValue) {
CFNumberRef cfFloat =
CFNumberCreate(kCFAllocatorDefault, kCFNumberFloatType, &prefValue);
CFPreferencesSetAppValue((CFStringRef)prefName, cfFloat, APP_ID);
CFRelease(cfFloat);
}
// Reads a named integer value from the stored preferences.
static int prefIntRead(NSString* prefName, BOOL* success) {
Boolean internalSuccess;
CFIndex result = CFPreferencesGetAppIntegerValue((CFStringRef)prefName,
APP_ID, &internalSuccess);
*success = internalSuccess;
return result;
}
// Writes a named integer value to the stored preferences.
static void prefIntWrite(NSString* prefName, int prefValue) {
CFPreferencesSetAppValue((CFStringRef)prefName,
(CFNumberRef)[NSNumber numberWithInt:prefValue],
APP_ID);
}
// Deletes the named preference values.
static void prefDelete(NSString* prefName) {
CFPreferencesSetAppValue((CFStringRef)prefName, NULL, APP_ID);
}
// Synchronizes the local preferences with the stored preferences.
static void prefSynchronize(void) { CFPreferencesAppSynchronize(APP_ID); }
// Internal version of accelGetData, with logging
int getData(sms_acceleration* accel, int calibrated, id logObject,
SEL logSelector) {
IOItemCount iSize = recordSize;
IOByteCount oSize = recordSize;
kern_return_t result;
if (running == NO) {
return -1;
}
memset(iRecord, 1, iSize);
memset(oRecord, 0, oSize);
LOG_2ARG(@" Querying device (%u, %d): ", sensors[sensorNum].function,
sensors[sensorNum].recordSize);
#if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1050
const size_t InStructSize = recordSize;
size_t OutStructSize = recordSize;
result = IOConnectCallStructMethod(connection,
function, // magic kernel function number
(const void*)iRecord, InStructSize,
(void*)oRecord, &OutStructSize);
#else // __MAC_OS_X_VERSION_MIN_REQUIRED 1050
result = IOConnectMethodStructureIStructureO(
connection,
function, // magic kernel function number
iSize, &oSize, iRecord, oRecord);
#endif // __MAC_OS_X_VERSION_MIN_REQUIRED 1050
if (result != KERN_SUCCESS) {
LOG(@"failed.\n");
running = NO;
return result;
} else {
LOG(@"succeeded.\n");
accel->x = getAxis(0, calibrated);
accel->y = getAxis(1, calibrated);
accel->z = getAxis(2, calibrated);
return 0;
}
}
// Given the returned record, extracts the value of the given axis. If
// calibrated, then zero G is 0.0, and one G is 1.0.
float getAxis(int which, int calibrated) {
// Get various values (to make code cleaner)
int indx = sensors[sensorNum].axes[which].index;
int size = sensors[sensorNum].axes[which].size;
float zerog = zeros[which];
float oneg = onegs[which];
// Storage for value to be returned
int value = 0;
// Although the values in the returned record should have the proper
// endianness, we still have to get it into the proper end of value.
#if (BYTE_ORDER == BIG_ENDIAN)
// On PowerPC processors
memcpy(((char*)&value) + (sizeof(int) - size), &oRecord[indx], size);
#endif
#if (BYTE_ORDER == LITTLE_ENDIAN)
// On Intel processors
memcpy(&value, &oRecord[indx], size);
#endif
value = signExtend(value, size);
if (calibrated) {
// Scale and shift for zero.
return ((float)(value - zerog)) / oneg;
} else {
return value;
}
}
// Extends the sign, given the length of the value.
int signExtend(int value, int size) {
// Extend sign
switch (size) {
case 1:
if (value & 0x00000080) value |= 0xffffff00;
break;
case 2:
if (value & 0x00008000) value |= 0xffff0000;
break;
case 3:
if (value & 0x00800000) value |= 0xff000000;
break;
}
return value;
}
// Returns the model name of the computer (e.g. "MacBookPro1,1")
NSString* getModelName(void) {
char model[32];
size_t len = sizeof(model);
int name[2] = {CTL_HW, HW_MODEL};
NSString* result;
if (sysctl(name, 2, &model, &len, NULL, 0) == 0) {
result = [NSString stringWithFormat:@"%s", model];
} else {
result = @"";
}
return result;
}
// Returns the current OS X version and build (e.g. "10.4.7 (build 8J2135a)")
NSString* getOSVersion(void) {
NSDictionary* dict =
[NSDictionary dictionaryWithContentsOfFile:
@"/System/Library/CoreServices/SystemVersion.plist"];
NSString* versionString = [dict objectForKey:@"ProductVersion"];
NSString* buildString = [dict objectForKey:@"ProductBuildVersion"];
NSString* wholeString =
[NSString stringWithFormat:@"%@ (build %@)", versionString, buildString];
return wholeString;
}
// Returns time within the current second in microseconds.
// long getMicroseconds() {
// struct timeval t;
// gettimeofday(&t, 0);
// return t.tv_usec;
//}
// Returns fake data given the time. Range is +/-1.
float fakeData(NSTimeInterval time) {
long secs = lround(floor(time));
int secsMod3 = secs % 3;
double angle = time * 10 * M_PI * 2;
double mag = exp(-(time - (secs - secsMod3)) * 2);
return sin(angle) * mag;
}