CoreAudio/PublicUtility/CASettingsStorage.cpp

/*
     File: CASettingsStorage.cpp
 Abstract: CASettingsStorage.h
  Version: 1.1
 
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*/
//==================================================================================================
//  Includes
//==================================================================================================
 
//  Self Include
#include "CASettingsStorage.h"
 
//  PublicUtility Includes
#include "CAAutoDisposer.h"
#include "CACFArray.h"
#include "CACFData.h"
#include "CACFDictionary.h"
#include "CACFDistributedNotification.h"
#include "CACFNumber.h"
 
//  Stamdard Library Includes
#include <string.h>
#include <sys/fcntl.h>
 
//==================================================================================================
//  CASettingsStorage
//==================================================================================================
 
CASettingsStorage::CASettingsStorage(const char* inSettingsFilePath, mode_t inSettingsFileAccessMode, CFPropertyListFormat inSettingsCacheFormat, bool inIsSingleProcessOnly, bool inIsReadOnly)
:
    mSettingsFilePath(NULL),
    mSettingsFileAccessMode(inSettingsFileAccessMode),
    mSettingsCache(CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks)),
    mSettingsCacheFormat(inSettingsCacheFormat),
    mSettingsCacheTime(),
    mSettingsCacheForceRefresh(true),
    mIsSingleProcessOnly(inIsSingleProcessOnly),
    mIsReadOnly(inIsReadOnly)
{
    size_t theLength = strlen(inSettingsFilePath);
    mSettingsFilePath = new char[theLength + 2];
    strlcpy(mSettingsFilePath, inSettingsFilePath, theLength + 2);
    
    mSettingsCacheTime.tv_sec = 0;
    mSettingsCacheTime.tv_nsec = 0;
    
    mSettingsCacheForceRefresh = true;
}
 
CASettingsStorage::~CASettingsStorage()
{
    delete[] mSettingsFilePath;
    
    if(mSettingsCache != NULL)
    {
        CFRelease(mSettingsCache);
    }
}
 
UInt32  CASettingsStorage::GetNumberKeys() const
{
    //  make sure our cache is up to date
    const_cast<CASettingsStorage*>(this)->RefreshSettings();
 
    return ToUInt32(CFDictionaryGetCount(mSettingsCache));
}
 
void    CASettingsStorage::GetKeys(UInt32 inNumberKeys, UInt32& outNumberKeys, CFStringRef* outKeys) const
{
    //  make sure our cache is up to date
    const_cast<CASettingsStorage*>(this)->RefreshSettings();
 
    CFDictionaryGetKeysAndValues(mSettingsCache, reinterpret_cast<const void**>(outKeys), NULL);
    outNumberKeys = inNumberKeys;
}
 
void    CASettingsStorage::CopyBoolValue(CFStringRef inKey, bool& outValue, bool inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  bools can be made from either CFBooleans or CFNumbers
        if(CFGetTypeID(theValue) == CFBooleanGetTypeID())
        {
            //  get the return value from the CF object
            outValue = CFBooleanGetValue(static_cast<CFBooleanRef>(theValue));
        }
        else if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the numeric value
            SInt32 theNumericValue = 0;
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt32Type, &theNumericValue);
            
            //  non-zero indicates true
            outValue = theNumericValue != 0;
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopySInt32Value(CFStringRef inKey, SInt32& outValue, SInt32 inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the return value from the CF object
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt32Type, &outValue);
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopyUInt32Value(CFStringRef inKey, UInt32& outValue, UInt32 inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the return value from the CF object
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt32Type, &outValue);
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopySInt64Value(CFStringRef inKey, SInt64& outValue, SInt64 inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the return value from the CF object
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt64Type, &outValue);
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopyUInt64Value(CFStringRef inKey, UInt64& outValue, UInt64 inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the return value from the CF object
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt64Type, &outValue);
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopyFloat32Value(CFStringRef inKey, Float32& outValue, Float32 inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the return value from the CF object
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberFloat32Type, &outValue);
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopyFloat64Value(CFStringRef inKey, Float64& outValue, Float64 inDefaultValue) const
{
    //  initialize the return value
    outValue = inDefaultValue;
    
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, NULL);
    
    //  for this type, NULL is an invalid value
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  get the return value from the CF object
            CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberFloat64Type, &outValue);
        }
        
        //  release the value since we aren't returning it
        CFRelease(theValue);
    }
}
 
void    CASettingsStorage::CopyNumberValue(CFStringRef inKey, CFNumberRef& outValue, CFNumberRef inDefaultValue) const
{
    //  initialize the return value
    outValue = NULL;
 
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, inDefaultValue);
    
    //  for this type, NULL is a valid value, but requires less work
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFNumberGetTypeID())
        {
            //  set the return value to the CF object we are returning
            outValue = static_cast<CFNumberRef>(theValue);
        }
        else
        {
            //  release the value since we aren't returning it
            CFRelease(theValue);
            
            //  set the return value to the default value
            outValue = inDefaultValue;
            
            //  and retain it
            CFRetain(outValue);
        }
    }
}
    
void    CASettingsStorage::CopyStringValue(CFStringRef inKey, CFStringRef& outValue, CFStringRef inDefaultValue) const
{
    //  initialize the return value
    outValue = NULL;
 
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, inDefaultValue);
    
    //  for this type, NULL is a valid value, but requires less work
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFStringGetTypeID())
        {
            //  set the return value to the CF object we are returning
            outValue = static_cast<CFStringRef>(theValue);
        }
        else
        {
            //  release the value since we aren't returning it
            CFRelease(theValue);
            
            //  set the return value to the default value
            outValue = inDefaultValue;
            
            //  and retain it
            CFRetain(outValue);
        }
    }
}
    
void    CASettingsStorage::CopyArrayValue(CFStringRef inKey, CFArrayRef& outValue, CFArrayRef inDefaultValue) const
{
    //  initialize the return value
    outValue = NULL;
 
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, inDefaultValue);
    
    //  for this type, NULL is a valid value, but requires less work
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFArrayGetTypeID())
        {
            //  set the return value to the CF object we are returning
            outValue = static_cast<CFArrayRef>(theValue);
        }
        else
        {
            //  release the value since we aren't returning it
            CFRelease(theValue);
            
            //  set the return value to the default value
            outValue = inDefaultValue;
            
            //  and retain it
            CFRetain(outValue);
        }
    }
}
    
void    CASettingsStorage::CopyDictionaryValue(CFStringRef inKey, CFDictionaryRef& outValue, CFDictionaryRef inDefaultValue) const
{
    //  initialize the return value
    outValue = NULL;
 
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, inDefaultValue);
    
    //  for this type, NULL is a valid value, but requires less work
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFDictionaryGetTypeID())
        {
            //  set the return value to the CF object we are returning
            outValue = static_cast<CFDictionaryRef>(theValue);
        }
        else
        {
            //  release the value since we aren't returning it
            CFRelease(theValue);
            
            //  set the return value to the default value
            outValue = inDefaultValue;
            
            //  and retain it
            CFRetain(outValue);
        }
    }
}
    
void    CASettingsStorage::CopyDataValue(CFStringRef inKey, CFDataRef& outValue, CFDataRef inDefaultValue) const
{
    //  initialize the return value
    outValue = NULL;
 
    //  get the raw value
    CFTypeRef theValue = NULL;
    CopyCFTypeValue(inKey, theValue, inDefaultValue);
    
    //  for this type, NULL is a valid value, but requires less work
    if(theValue != NULL)
    {
        //  make sure we are dealing with the right kind of CF object
        if(CFGetTypeID(theValue) == CFDataGetTypeID())
        {
            //  set the return value to the CF object we are returning
            outValue = static_cast<CFDataRef>(theValue);
        }
        else
        {
            //  release the value since we aren't returning it
            CFRelease(theValue);
            
            //  set the return value to the default value
            outValue = inDefaultValue;
            
            //  and retain it
            CFRetain(outValue);
        }
    }
}
 
void    CASettingsStorage::CopyCFTypeValue(CFStringRef inKey, CFTypeRef& outValue, CFTypeRef inDefaultValue) const
{
    //  make sure our cache is up to date
    const_cast<CASettingsStorage*>(this)->RefreshSettings();
 
    //  check to see if we have a value for the given key
    if(!CFDictionaryGetValueIfPresent(mSettingsCache, inKey, &outValue))
    {
        //  the key wasn't in the cache, so return the default value
        outValue = inDefaultValue;
    }
        
    //  make sure we retain the return value
    if(outValue != NULL)
    {
        CFRetain(outValue);
    }
}
 
void    CASettingsStorage::SetSInt32Value(CFStringRef inKey, SInt32 inValue)
{
    CACFNumber theValue(inValue);
    SetCFTypeValue(inKey, theValue.GetCFNumber());
}
 
void    CASettingsStorage::SetUInt32Value(CFStringRef inKey, UInt32 inValue)
{
    CACFNumber theValue(inValue);
    SetCFTypeValue(inKey, theValue.GetCFNumber());
}
 
void    CASettingsStorage::SetSInt64Value(CFStringRef inKey, SInt64 inValue)
{
    CACFNumber theValue(inValue);
    SetCFTypeValue(inKey, theValue.GetCFNumber());
}
 
void    CASettingsStorage::SetUInt64Value(CFStringRef inKey, UInt64 inValue)
{
    CACFNumber theValue(inValue);
    SetCFTypeValue(inKey, theValue.GetCFNumber());
}
 
void    CASettingsStorage::SetFloat32Value(CFStringRef inKey, Float32 inValue)
{
    CACFNumber theValue(inValue);
    SetCFTypeValue(inKey, theValue.GetCFNumber());
}
 
void    CASettingsStorage::SetFloat64Value(CFStringRef inKey, Float64 inValue)
{
    CACFNumber theValue(inValue);
    SetCFTypeValue(inKey, theValue.GetCFNumber());
}
 
void    CASettingsStorage::SetNumberValue(CFStringRef inKey, CFNumberRef inValue)
{
    SetCFTypeValue(inKey, inValue);
}
 
void    CASettingsStorage::SetStringValue(CFStringRef inKey, CFStringRef inValue)
{
    SetCFTypeValue(inKey, inValue);
}
 
void    CASettingsStorage::SetArrayValue(CFStringRef inKey, CFArrayRef inValue)
{
    SetCFTypeValue(inKey, inValue);
}
 
void    CASettingsStorage::SetDictionaryValue(CFStringRef inKey, CFDictionaryRef inValue)
{
    SetCFTypeValue(inKey, inValue);
}
 
void    CASettingsStorage::SetDataValue(CFStringRef inKey, CFDataRef inValue)
{
    SetCFTypeValue(inKey, inValue);
}
 
void    CASettingsStorage::SetCFTypeValue(CFStringRef inKey, CFTypeRef inValue)
{
    //  make sure our cache is up to date
    RefreshSettings();
    
    //  add the new key/value to the dictionary
    CFDictionarySetValue(mSettingsCache, inKey, inValue);
    
    //  write the settings to the file
    SaveSettings();
}
 
void    CASettingsStorage::RemoveValue(CFStringRef inKey)
{
    //  make sure our cache is up to date
    RefreshSettings();
    
    //  remove the given key
    CFDictionaryRemoveValue(mSettingsCache, inKey);
    
    //  write the settings to the file
    SaveSettings();
}
 
void    CASettingsStorage::RemoveAllValues()
{
    //  make sure our cache is up to date
    RefreshSettings();
    
    //  remove the given key
    CFDictionaryRemoveAllValues(mSettingsCache);
    
    //  write the settings to the file
    SaveSettings();
}
 
void    CASettingsStorage::SendNotification(CFStringRef inName, CFDictionaryRef inData, bool inPostToAllSessions) const
{
    CACFDistributedNotification::PostNotification(inName, inData, inPostToAllSessions);
}
 
void    CASettingsStorage::ForceRefresh()
{
    mSettingsCacheForceRefresh = true;
}
 
inline bool operator<(const struct timespec& inX, const struct timespec& inY)
{
    return ((inX.tv_sec < inY.tv_sec) || ((inX.tv_sec == inY.tv_sec) && (inX.tv_nsec < inY.tv_nsec)));
}
 
void    CASettingsStorage::RefreshSettings()
{
    //  if this storage is only supporting a single process, there is no need to hit the disk unless
    //  required to by it being the first time or if the refresh is specifically forced for some reason
    if(!mIsSingleProcessOnly || (mSettingsCache == NULL) || ((mSettingsCacheTime.tv_sec == 0) && (mSettingsCacheTime.tv_nsec == 0)) || mSettingsCacheForceRefresh)
    {
        //  first, we need to stat the file to check the mod date, this has the side effect of also
        //  telling us if the file exisits
        struct stat theFileInfo;
        int theStatError = stat(mSettingsFilePath, &theFileInfo);
        
        //  we use this boolean to make error recovery easier since we need a case for when there's no file anyway
        bool theSettingsWereCached = false;
        bool theSettingsNeedSaving = true;
        
        if(theStatError == 0)
        {
            //  stat says there is something there, only have to do work if we either don't have a cache or the cache is out of date
            if((mSettingsCache == NULL) || (mSettingsCacheTime < theFileInfo.st_mtimespec) || mSettingsCacheForceRefresh)
            {
                //  open the file
                FILE* theFile = fopen(mSettingsFilePath, "r");
                if(theFile != NULL)
                {
                    //  lock the file (this call blocks until the lock is taken)
                    int theError = flock(fileno(theFile), LOCK_EX);
                    if(theError == 0)
                    {
                        //  get the length of the file
                        fseek(theFile, 0, SEEK_END);
                        size_t theFileLength = static_cast<size_t>(ftell(theFile));
                        fseek(theFile, 0, SEEK_SET);
                        
                        if(theFileLength > 0)
                        {
                            //  allocate a block of memory to hold the data in the file
                            CAAutoFree<Byte> theRawFileData(theFileLength);
                            
                            //  read all the data in
                            fread(static_cast<Byte*>(theRawFileData), theFileLength, 1, theFile);
                            
                            //  release the lock
                            flock(fileno(theFile), LOCK_UN);
                            
                            //  put it into a CFData object
                            CACFData theRawFileDataCFData(static_cast<Byte*>(theRawFileData), static_cast<UInt32>(theFileLength));
                            
                            //  get rid of the existing cache
                            if(mSettingsCache != NULL)
                            {
                                CFRelease(mSettingsCache);
                                mSettingsCache = NULL;
                            }
                            
                            //  parse the data as a property list
                            mSettingsCache = (CFMutableDictionaryRef)CFPropertyListCreateWithData(NULL, theRawFileDataCFData.GetCFData(), kCFPropertyListMutableContainersAndLeaves, NULL, NULL);
                            
                            //  check to be sure we parsed a plist out of the file
                            if(mSettingsCache != NULL)
                            {
                                //  save the date of the cache
                                mSettingsCacheTime = theFileInfo.st_mtimespec;
                                
                                //  mark that we're done
                                theSettingsWereCached = true;
                                theSettingsNeedSaving = false;
                            }
                        }
                    }
                    
                    //  close the file
                    fclose(theFile);
                    mSettingsCacheForceRefresh = false;
                }
            }
            else
            {
                //  nothing to do since the file was older than the cached data
                theSettingsNeedSaving = false;
                theSettingsWereCached = true;
            }
        }
        
        //  if there was a failure, we need to clean up 
        if((theStatError != 0) || theSettingsNeedSaving || !theSettingsWereCached)
        {
            //  we get here if either there isn't a file or something wacky happenned while parsing it
            //  so, make sure we have a valid cache dictionary
            if(mSettingsCache == NULL)
            {
                mSettingsCache = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
            }
            
            mSettingsCacheTime.tv_sec = 0;
            mSettingsCacheTime.tv_nsec = 0;
            
            if((theStatError != 0) || theSettingsNeedSaving)
            {
                SaveSettings();
            }
        }
    }
}
 
void    CASettingsStorage::SaveSettings()
{
    if(!mIsReadOnly && (mSettingsCache != NULL))
    {
        //  make a CFData that contains the new settings
        CACFData theNewRawPrefsCFData(CFPropertyListCreateData(NULL, mSettingsCache, mSettingsCacheFormat, 0, NULL), true);
        
        //  open the file for writing
        FILE* theFile = fopen(mSettingsFilePath, "w+");
        if(theFile != NULL)
        {
            //  lock the file (this call blocks until the lock is taken)
            int theError = flock(fileno(theFile), LOCK_EX);
            if(theError == 0)
            {
                //  set the file access mode if necessary
                if(mSettingsFileAccessMode != 0)
                {
                    fchmod(fileno(theFile), mSettingsFileAccessMode);
                }
                
                //  write the data
                fwrite(theNewRawPrefsCFData.GetDataPtr(), theNewRawPrefsCFData.GetSize(), 1, theFile);
                
                //  flush the file to be sure it is all on disk
                fflush(theFile);
                
                //  release the lock
                flock(fileno(theFile), LOCK_UN);
            
                //  close the file
                fclose(theFile);
                
                //  stat the file to get the mod date
                struct stat theFileInfo;
                stat(mSettingsFilePath, &theFileInfo);
                
                //  save the mod date
                mSettingsCacheTime = theFileInfo.st_mtimespec;
            }
            else
            {
                //  close the file
                fclose(theFile);
            }
        }
    }
}


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