Re: [Libguestfs] [PATCH 2/2] lib: utf16: Fix const-correctness issues in _hivex_recode function.

On Tuesday 31 December 2013 14:27:11 Richard W.M. Jones wrote: > This patch assumes that iconv doesn't actually modify the > input buffer, even though it is declared as char *. > --- > [...] > @@ -51,10 +51,11 @@ _hivex_recode (char *input_encoding, const char > *input, size_t input_len, errno = err; > return NULL; > } > - char *inp = input; > + const char *inp = input; > char *outp = out; > > - size_t r = iconv (ic, &inp, &inlen, &outp, &outlen); > + /* Surely iconv doesn't really modify the input buffer? XXX */ > + size_t r = iconv (ic, (char **) &inp, &inlen, &outp, &outlen); > if (r == (size_t) -1) { This (the constness of the input argument) is the difference between the iconv implementation provided in GNU libc and the other ones, even though it reflects POSIX [1].

The iconv.m4 module in gnulib checks for this too, and AC_DEFINE's ICONV_CONST as "const" (or empty) depending on the actual prototype of iconv(3). [1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/iconv.html