Error on IOS : malloc: *** error for object 0x12bc17cc0: pointer being freed was not allocated

[maksimus1982]

Hello !
I have python class, which reads dafa from DBF file:

from os.path import exists, join, split
import sys
import struct, datetime, decimal, itertools
FILE_ENCODING = 'windows-1251'

class DBF:
@staticmethod
def dbfreader(f, encoding='windows-1251'):
numrec, lenheader = struct.unpack('<xxxxLH22x', f.read(32))
numfields = (lenheader - 33) // 32

    fields = []
    for _ in range(numfields):
        name, typ, size, deci = struct.unpack('<11sc4xBB14x', f.read(32))
        name = name.decode(encoding).replace('\0', '')
        typ = typ.decode(encoding)
        fields.append((name, typ, size, deci))
        print("fields: ",name, typ, size, deci)
    yield [field[0] for field in fields]
    yield [tuple(field[1:]) for field in fields]
    
    terminator = f.read(1)
    assert terminator == b'\r'

    fields.insert(0, ('DeletionFlag', 'C', 1, 0))
    fmt = ''.join(['%ds' % fieldinfo[2] for fieldinfo in fields])
    fmtsiz = struct.calcsize(fmt)

    for _ in range(numrec):
        record = struct.unpack(fmt, f.read(fmtsiz))
        if record[0] != b' ':
            continue
        result = []
        for (name, typ, size, deci), value in zip(fields, record):
            if name == 'DeletionFlag':
                continue
            if typ == "N":
                value = value.decode(encoding).replace('\0', '').lstrip()
                if value == '':
                    value = 0
                elif deci:
                    value = decimal.Decimal(value)
                else:
                    value = int(value)
            elif typ == "C":
                value = value.decode(encoding).rstrip()
            elif typ == 'D':
                y, m, d = int(value[:4]), int(value[4:6]), int(value[6:8])
                value = datetime.date(y, m, d)
            elif typ == 'L':
                value = (value.decode(encoding) in 'YyTt' and 'T') or \
                        (value.decode(encoding) in 'NnFf' and 'F') or '?'
            result.append(value)
        yield result
       
def __init__(self, filename):
    filename = join( split( sys._getframe().f_code.co_filename )[0], filename )
  
    if not exists( filename ):
        print("filename not found",filename)
        fError( error_DBFfileNE + " '" + filename + "'." )

    try:
        f = open(filename, 'rb')
    except IOError:
        print("filename can open",filename)
        fError( error_DBFfileNO + " '" + filename + "'." )


    try:
        recordList = list(self.dbfreader(f))
        print("Records :",recordList)
    except Exception as e:
        print("Record list failed for file",e)
        fError( error_DBFfileNO + " '" + filename + "'." )

    f.close()

    self.fieldnames, self.fieldspecs, self.records = recordList[0], recordList[1], recordList[2:]
    self.fieldnamesDict = {}
    for name in self.fieldnames:
        self.fieldnamesDict[name] = self.fieldnames.index(name)

def __call__(self):
    for record in self.records:
        record_dict = {}
        for name in self.fieldnamesDict:
            record_dict[name] = record[self.fieldnamesDict[name]]
        yield record_dict

and class usage like this : globals()['db'] = DBF(filename)

On IOS i catch a bug :
// run app
let file = fopen(appPath, "r")
let result = PyRun_SimpleFileEx(file, appPath, 1)
if (result != 0) {
print("Python program completed with error.")
}

Py_Finalize()

flutter: Finished unpacking application archive in 0:00:00.158748
Swift runPython(appPath: /Users/shadmin/Library/Developer/CoreSimulator/Devices/088C3E3D-281F-4AAE-B109-8C030C09390B/data/Containers/Data/Application/ECD9A428-784D-4A62-98A6-C9532A6ACBE8/Library/Application Support/flet/app/_02_111_gear_calc.py, modulePaths: [])
Runner(65895,0x11b409280) malloc: *** error for object 0x12bc17cc0: pointer being freed was not allocated
Runner(65895,0x11b409280) malloc: *** set a breakpoint in malloc_error_break to debug

But on Android all works fine. I can print all DBF content to console for example.

Please help :)

[FeodorFitsner]

Does "hello world" work on iOS simulator for you?

[maksimus1982]

Yes! Basically everything works on iOS. And I think I found what causes the error.
If i remove "import decimal" and change #value = decimal.Decimal(value) to value = float(value) in DBF python class - everything works fine :)

I don't no why