iconv prototype (was: Re: lftp-pre3.0.0-20040115)

2004-01-16 Thread Alexander V. Lukyanov 
It seems that char** is correct, according to Ulrich Drepper:
   http://sources.redhat.com/ml/bug-glibc/2000-10/msg6.html
I was under impression of the reverse, sorry about that.

There was also some iconv discussion on abiword mailing list back in 2001:
   http://www.abisource.com/mailinglists/abiword-dev/01/August/0543.html

--
   Alexander.  | http://www.yars.free.net/~lav/

Re: lftp-pre3.0.0-20040115

2004-01-15 Thread Glenn Maynard 
On Thu, Jan 15, 2004 at 09:51:22AM +0300, Alexander V. Lukyanov wrote:
 What's new:

Had some trouble building from CVS:

automake outputs:

Makefile.am:3: AM_GNU_GETTEXT in `configure.ac' but `intl' not in SUBDIRS
src/Makefile.am:42: variable `SOCKSLIBS' not defined

The second is just an AC_SUBST.  I'm not sure about the first, but it's
apparently not fatal.

My system has socklen_t, and socklen.m4 is defining lftp_socklen_t to nothing,
instead of leaving it undefined.

buffer.cc is missing errno.h.

buffer.cc:307: error: invalid conversion from `const char**' to `char**'
iconv takes a char**, not const char**.

Now I'm getting

make: *** No rule to make target `libpty.la', needed by `all-am'.  Stop.

I don't feel like stepping through libtool (this is why I hate libtool;
it's brittle and impossible to diagnose).  If config.log or something
will help, let me know.

-- 
Glenn Maynard
Index: configure.ac
===
RCS file: /home/lav/cvsroot/lftp/configure.ac,v
retrieving revision 1.19
diff -p -u -r1.19 configure.ac
--- configure.ac17 Dec 2003 08:33:52 -  1.19
+++ configure.ac15 Jan 2004 08:22:10 -
@@ -162,6 +162,7 @@ if test x$with_socksdante = xyes; then
AC_CHECK_LIB(socks, main, [SOCKSLIBS=-lsocks],
   [AC_MSG_ERROR(cannot find -lsocks library)])
 fi
+AC_SUBST(SOCKSLIBS)
 LIBS=$LIBS $SOCKSLIBS
 if test -n $SOCKSLIBS; then
AC_CHECK_FUNCS([Rpoll])
Index: m4/socklen.m4
===
RCS file: /home/lav/cvsroot/lftp/m4/socklen.m4,v
retrieving revision 1.3
diff -p -u -r1.3 socklen.m4
--- m4/socklen.m4   17 Dec 2003 06:37:42 -  1.3
+++ m4/socklen.m4   15 Jan 2004 08:22:10 -
@@ -44,7 +44,7 @@ AC_DEFUN(TYPE_SOCKLEN_T,
 AC_LANG_POP(C++)
   ])
   AC_MSG_RESULT($lftp_cv_socklen_t_equiv)
+ AC_DEFINE_UNQUOTED(lftp_socklen_t, $lftp_cv_socklen_t_equiv,
+[type to use in place of socklen_t if not defined])
fi
-   AC_DEFINE_UNQUOTED(lftp_socklen_t, $lftp_cv_socklen_t_equiv,
- [type to use in place of socklen_t if not defined])
 ])
Index: src/buffer.cc
===
RCS file: /home/lav/cvsroot/lftp/src/buffer.cc,v
retrieving revision 1.38
diff -p -u -r1.38 buffer.cc
--- src/buffer.cc   14 Jan 2004 16:16:59 -  1.38
+++ src/buffer.cc   15 Jan 2004 08:22:13 -
@@ -19,6 +19,7 @@
  */
 
 #include config.h
+#include errno.h
 #include buffer.h
 #include xmalloc.h
 #include FileAccess.h
@@ -303,7 +304,7 @@ try_again:
store_size=buffer_allocated-(store_buf-buffer);
const char *base_buf=put_buf;
// do the translation
-   size_t res=iconv(backend_translate,put_buf,put_size,store_buf,store_size);
+   size_t 
res=iconv(backend_translate,(char**)put_buf,put_size,store_buf,store_size);
in_buffer+=store_buf-(buffer+buffer_ptr+in_buffer);
if(from_untranslated)
   untranslated-Skip(put_buf-base_buf);

Re: lftp-pre3.0.0-20040115

2004-01-15 Thread Alexander V. Lukyanov 
On Thu, Jan 15, 2004 at 03:23:52AM -0500, Glenn Maynard wrote:
 On Thu, Jan 15, 2004 at 09:51:22AM +0300, Alexander V. Lukyanov wrote:
  What's new:

 Had some trouble building from CVS:

I have forgotten to commit some changes to CVS. Thanks for the fixes, I have
applied them.

The iconv case is the nastiest, since iconv should actually take const char**
as source string.

 Makefile.am:3: AM_GNU_GETTEXT in `configure.ac' but `intl' not in SUBDIRS

This is probably because of old version of automake. intl is optional now.

--
   Alexander.

Re: lftp-pre3.0.0-20040115

2004-01-15 Thread Alexander V. Lukyanov 
On Thu, Jan 15, 2004 at 07:14:10AM -0500, Glenn Maynard wrote:
 On Thu, Jan 15, 2004 at 02:19:41PM +0300, Alexander V. Lukyanov wrote:
  The iconv case is the nastiest, since iconv should actually take const char**
  as source string.
 
 I don't think so.  Try this:
 
 #include string.h
 void func( const char **p ) { }
 main()
 {
   char *str = strdup(abc);
   func( str );
 }
 
 test.cc:6: error: invalid conversion from `char**' to `const char**'

It's actually the reverse. I.e. iconv on your system is declared as
iconv(...,char **inbuf,...)

while correct prototype is
iconv(...,const char **inbuf,...)

 (If you can't figure out the reason for the above, I'll explain it, but
 it's far too late right now.  :)

I understand the reason. An autoconf test should be written to determine the iconv
prototype and depending on that test a const cast should be used.

BTW, if you install GNU libiconv which has correct iconv prototype, lftp would
compile just fine.

-- 
   Alexander.

Re: lftp-pre3.0.0-20040115

2004-01-15 Thread Alexander V. Lukyanov 
On Thu, Jan 15, 2004 at 04:51:48PM +0300, Alexander V. Lukyanov wrote:
 I understand the reason. An autoconf test should be written to determine the iconv
 prototype and depending on that test a const cast should be used.

I have found that AM_ICONV macro from gettext does the job and defines
ICONV_CONST to const if the const is needed.

So the cast become (ICONV_CONST char**)put_buf

--
   Alexander.  | http://www.yars.free.net/~lav/

Re: lftp-pre3.0.0-20040115

2004-01-15 Thread Glenn Maynard 
On Thu, Jan 15, 2004 at 04:51:48PM +0300, Alexander V. Lukyanov wrote:
  #include string.h
  void func( const char **p ) { }
  main()
  {
  char *str = strdup(abc);
  func( str );
  }
  
  test.cc:6: error: invalid conversion from `char**' to `const char**'
 
 It's actually the reverse. I.e. iconv on your system is declared as
   iconv(...,char **inbuf,...)
   
 while correct prototype is
   iconv(...,const char **inbuf,...)

Not inherently, since then you couldn't pass a pointer to a buffer that
*isn't* const, without another cast.  That's what I was showing.

Neither is correct--the desired constness can't be expressed in C++.

-- 
Glenn Maynard

Re: lftp-pre3.0.0-20040115

2004-01-15 Thread Glenn Maynard 
On Thu, Jan 15, 2004 at 06:29:59PM +0300, Alexander V. Lukyanov wrote:
 I have found that AM_ICONV macro from gettext does the job and defines
 ICONV_CONST to const if the const is needed.
 
 So the cast become (ICONV_CONST char**)put_buf

The safest way to do this is to use const_castconst char *(put_buf);
it'll catch unwanted type changes, and doesn't need an autoconf test:
it's harmless to do if not needed, since it'll still catch type errors.

-- 
Glenn Maynard