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POC++ using cdb_read returns extra characters on some reads
 

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  1. POC++ using cdb_read returns extra characters on some reads
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    <p>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)). </p> <p>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.</p> <p>I get the character if I use cdb_read() or cdb_getdata() (the commented out code below).</p> <p>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.</p> <p>Any advice or assistance is greatly appreciated. </p> <pre><code>char* HashReducer::getValueFromDb(const string &amp;id, vector &lt;struct cdb *&gt; &amp;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,&amp;hex_len); char *value = NULL; vector &lt;struct cdb *&gt;::iterator my_iter = myHashFiles.begin(); vector &lt;struct cdb *&gt;::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 &amp;&amp; !value ; my_iter++) { //cerr &lt;&lt; "\n looking for this MD5:" &lt;&lt; id &lt;&lt; " hex(" &lt;&lt; hex_value &lt;&lt; ") \n"; if (cdb_find(*my_iter, hex_value, hex_len)){ //cerr &lt;&lt; "\n\nI found the key " &lt;&lt; id &lt;&lt; " and it is " &lt;&lt; cdb_datalen(*my_iter) &lt;&lt; " 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 &lt;&lt; "\n\nThe value is:" &lt;&lt; value &lt;&lt; " len is:" &lt;&lt; strlen(value)&lt;&lt; "\n\n"; }; } } catch (...){} return value; } </code></pre>
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