[Shapelib] Memory issue reading string field?

[Brian Peschel]

  I think I just found it.  I was loading the value into an std::string, 
so the length shouldn't matter, but then loading it back to to char* 
with a newline and didn't account for the newline. <sigh>

> I'm really "out", but if the "size" of the string can cause memory
> corruptions, so, maybe, the program have a "limit" to the size of the
> string, but is not checking if this limite is been observed...
>
> If the code is in C or C++, probably you are writting after the size of the
> variable.
>
> Like if I declare a variable as char name [5]
>
> And then try to put "PESCHEL" in it.
>
> If the program don't check this, you will write over memory that was not
> meant to.
>
> Well.
>
> Only an "educated guess" I think...
>
> 2010/8/19 Brian Peschel<brianp at occinc.com>
>
>>   I have a simple DBF file I am trying to read:
>>
>> dBase Reader and Converter V. 0.8, (c) 2002 - 2003 by Bjoern Berg
>>
>> -- File statistics
>> dBase version.........:          FoxBase+/dBASE III+ (without memo)
>> Date of last update...:          1995-07-26
>> Number of records.....:          1414347 (001594cbd)
>> Length of header......:          97 (0061d)
>> Record length.........:          81 (0051d)
>> Columns in file.......:          2
>> Rows in file..........:          1414347
>>
>> +---------------+-------+---------------+---------------+---------------+
>> | field name    | type  | field adress  | length        | field dec.    |
>> +---------------+-------+---------------+---------------+---------------+
>> |           ID  |   N   |        0      |  10           |   0           |
>> |       String  |   C   |        0      |  70           |   0           |
>> +---------------+-------+---------------+---------------+---------------+
>>
>> I am seeing memory corruption in my program after reading this combo from
>> the DBF.
>>           ID:    1374067
>>       String: UNITED STATES DEPARTMENT OF THE INTERIOR PATUXENT WILDLIFE
>> RESEARCH CE
>> What makes this interesting is the string is 70 characters long (which is
>> the width of the field).
>>
>> If I change the string in the DBF to:
>>           ID:    1374067
>>       String: US DEPT OF THE INTERIOR PATUXENT WILDLIFE RESEARCH CENTER
>> (which is 57 characters) I no longer have any memory corruption.
>>
>> I tries this on both 1.2.10 and 1.3.0b2.  Any ideas?
>>
>> - B