C++ using cdb_read returns extra characters on some reads
- by Moe Be
Hi All,
I am using the following function to loop through a couple of open CDB hash tables. Sometimes the value for a given key is returned along with an additional character (specifically a CTRL-P (a DLE character/0x16/0o020)).
I have checked the cdb key/value pairs with a couple of different utilities and none of them show any additional characters appended to the values.
I get the character if I use cdb_read() or cdb_getdata() (the commented out code below).
If I had to guess I would say I am doing something wrong with the buffer I create to get the result from the cdb functions.
Any advice or assistance is greatly appreciated.
char* HashReducer::getValueFromDb(const string &id, vector <struct cdb *> &myHashFiles)
{
unsigned char hex_value[BUFSIZ];
size_t hex_len;
//construct a real hex (not ascii-hex) value to use for database lookups
atoh(id,hex_value,&hex_len);
char *value = NULL;
vector <struct cdb *>::iterator my_iter = myHashFiles.begin();
vector <struct cdb *>::iterator my_end = myHashFiles.end();
try
{
//while there are more databases to search and we have not found a match
for(; my_iter != my_end && !value ; my_iter++)
{
//cerr << "\n looking for this MD5:" << id << " hex(" << hex_value << ") \n";
if (cdb_find(*my_iter, hex_value, hex_len)){
//cerr << "\n\nI found the key " << id << " and it is " << cdb_datalen(*my_iter) << " long\n\n";
value = (char *)malloc(cdb_datalen(*my_iter));
cdb_read(*my_iter,value,cdb_datalen(*my_iter),cdb_datapos(*my_iter));
//value = (char *)cdb_getdata(*my_iter);
//cerr << "\n\nThe value is:" << value << " len is:" << strlen(value)<< "\n\n";
};
}
}
catch (...){}
return value;
}
