def create(self):
"""Creates new database"""
f = self.file
head = util.read_meta(f,"hDatabases")
#Generate ID
ID = util.read_meta(f,"cDatabases")+1
util.write_meta(f,"cDatabases",ID)
db = self.find_last()
bdata = struct.pack("=I32sQQ",ID,self.name,db.addr,0)
f.seek(0,2)
self.addr = f.tell()
#Write data
f.write(bdata)
#Bind tail
util.write_meta(f,"tDatabases",self.addr)
#Bind previous node
db.next = self.addr
f.seek(db.addr+44)
bdata = struct.pack("=I",db.next)
f.write(bdata)
return Result(0,"Database created")
def init(self):
"""
Initialization
1. Create file
2. Write all meta with defaults
3. Write credentials
"""
if os.path.isfile(self.file_name):
return Result(3,"Initialization is already done")
self.file = open(self.file_name,"wb")
self.file.close()
self.file = open(self.file_name,"rb+")
f = self.file
#Write meta
for key,value in self.meta.iteritems():
util.write_meta(f,key,value[3])
#Write default database
db = Database(f,"_default")
db.prev = self.meta["hDatabases"][1]
db.id = 0
db.next = 0
bdata = struct.pack("=I32sQQ",db.id, db.name, db.prev, db.next)
f.seek(0,2)
db.addr = f.tell()
f.write(bdata)
#Write head and tail
util.write_meta(f,"hDatabases",db.addr)
util.write_meta(f,"tDatabases",db.addr)
f.flush()
return Result(0,"Initialization has beend done")
def init():
"""
Initialization
1. Create file
2. Write all meta with zero
3. Write credentials
"""
if os.path.isfile("data.db"):
return Result(3,"Initialization is already done")
f = open("data.db","wb")
name = settings.credentials["name"]
fx.set_name(f,name)
version_a = settings.credeantials["version_a"]
version_b = settings.credeantials["version_b"]
fx.set_version(f,version_a,version_b)
util.write_meta(f,"hDatabases",0)
util.write_meta(f,"hTables",0)
util.write_meta(f,"hColumns",0)
util.write_meta(f,"hKeys",0)
util.write_meta(f,"hSerials",0)
util.write_meta(f,"cDatabases",0)
util.write_meta(f,"cTables",0)
util.write_meta(f,"cKeys",0)
util.write_meta(f,"cSerials",0)
f.close()
return Result(0,"Initialized")
