On 26 Oct 2009, kris.slowin...@gmail.com wrote:
> I have the following function declaration: void
> createCiphertext(char* plaintext, char**ciphertext); which is
> supposed to allocate memory to *ciphertext. I have a Splint warning
> that *ciphertext may be null and that createCiphertext needs to
> annotate that in the declaration, but I dont know how to annotate
> *ciphertext. Any help?
Does createCiphertext() have anything like this,
if(ciphertext == NULL)
return;
You might want to check that this value is non-NULL depending on the
circumstances. I don't know if this is an API that many programmers
will use or if it is local to the module (in which case you should use
static).
Another thing is that you can easily change the API so that this error
can not occur. Ie,
/* returns ciphertext */
/*...@only@*/ /*...@null@*/ char * createCiphertext(char* plaintext);
The /*...@only@*/ and /*...@null@*/ portions are splint annotations.
Back to your original question, I am not quite sure which portion of
the pointer needs to be null/non-null. I am guessing that with things
the way you have them the annoation is one of,
void
createCiphertext(char* plaintext, /*...@notnull@*/ char**ciphertext);
void
createCiphertext(char* plaintext, /*...@null@*/ char**ciphertext);
typedef /*...@notnull@*/ char * good_ptr;
void createCiphertext(char* plaintext, good_ptr *ciphertext);
typedef /*...@null@*/ char * bad_ptr;
void createCiphertext(char* plaintext, bad_ptr *ciphertext);
I think you have given too little context to know which version and it
is better if you known what you are doing than being spoon feed.
The null annotations are detailed in sections 2 of the manual.
http://www.splint.org/manual/html/sec2.html
http://www.splint.org/manual/html/appC.html
hth,
Bill Pringlemeir.
--
I believe that sex is one of the most beautiful, natural, wholesome things
that money can buy. - Steve Martin
_______________________________________________
splint-discuss mailing list
splint-discuss@mail.cs.virginia.edu
http://www.cs.virginia.edu/mailman/listinfo/splint-discuss
