Re: ptsname_r on OSF/1

[Bruno Haible]

Let's try to deal with the compilation error first:

> * OSF/1 5.1:
> 
> Compilation error
> 
> cc -O -DHAVE_CONFIG_H -I. -I..  -DGNULIB_STRICT_CHECKING=1  
> -DIN_GNULIB_TESTS=1  -I. -I.  -I.. -I./..  -I../gllib -I./../gllib     -c 
> test-ptsname_r.c
> cc: Error: test-ptsname_r.c, line 22: In the initializer for 
> signature_check22, "ptsname_r" is not declared. (undeclared)
> SIGNATURE_CHECK (ptsname_r, int, (int, char *, size_t));
> ^
> *** Exit 1

OSF/1 has a function
  extern int ptsname_r __((int, char *, int));

and the manual page says:

  [Tru64 UNIX]  The ptsname_r() function is an obsolete reentrant version of
  the ptsname() function.  It is supported in order to maintain backward com-
  patibility with previous versions of the operating system and should not be
  used in new designs.

This function returns -1, not errno. This is allowed by the glibc documentation
and the Linux man page.

But this function ignores its buflen argument. I get trace output like this from
fprintf (stderr, "buflen=%d -> %d %d %s\n", (int)buflen, result, errno, buffer);

calling with buflen=0
buflen=0 -> 0 0 /dev/pts/9
calling with buflen=1
buflen=1 -> 0 0 /dev/pts/9
calling with buflen=2
buflen=2 -> 0 0 /dev/pts/9
calling with buflen=3
buflen=3 -> 0 0 /dev/pts/9
calling with buflen=4
buflen=4 -> 0 0 /dev/pts/9
calling with buflen=5
buflen=5 -> 0 0 /dev/pts/9
calling with buflen=6
buflen=6 -> 0 0 /dev/pts/9
calling with buflen=7
buflen=7 -> 0 0 /dev/pts/9
calling with buflen=8
buflen=8 -> 0 0 /dev/pts/9
calling with buflen=9
buflen=9 -> 0 0 /dev/pts/9
calling with buflen=10
buflen=10 -> 0 0 /dev/pts/9
calling with buflen=11
calling with buflen=12
calling with buflen=13
calling with buflen=14
calling with buflen=15
calling with buf=NULL
Segmentation fault (core dumped)

So we cannot use this function. I'm applying this fix, which makes it use the
same replacement as on other platforms. Still, the test fails:

PASS: test-ptsname
test-ptsname_r.c:77: assertion failed
FAIL: test-ptsname_r

Cause: ptsname_r fails with errno = ENOENT.


2011-11-10  Bruno Haible  <address@hidden>

        ptsname_r: Avoid compilation error on OSF/1 5.1.
        * lib/stdlib.in.h (ptsname_r): Override if REPLACE_PTSNAME_R is 1.
        * m4/stdlib_h.m4 (gl_STDLIB_H_DEFAULTS): Initialize REPLACE_PTSNAME_R.
        * m4/ptsname_r.m4 (gl_FUNC_PTSNAME_R): Set REPLACE_PTSNAME_R if the
        function is not declared or incompatibly declared.
        * modules/stdlib (Makefile.am): Substitute REPLACE_PTSNAME_R.
        * modules/ptsname_r (Depends-on, configure.ac): Update.
        * doc/glibc-functions/ptsname_r.texi: Mention the OSF/1 problems.

--- doc/glibc-functions/ptsname_r.texi.orig     Thu Nov 10 13:43:36 2011
+++ doc/glibc-functions/ptsname_r.texi  Thu Nov 10 13:35:40 2011
@@ -11,6 +11,13 @@
 MacOS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8,
 AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 11 2010-11, Cygwin 1.7.9, mingw,
 MSVC 9, BeOS.
address@hidden
+This function is not declared unless @code{_REENTRANT} is defined,
+on some platforms:
+OSF/1 5.1.
address@hidden
+This function has an incompatible declaration on some platforms:
+OSF/1 5.1.
 @end itemize
 
 Portability problems not fixed by Gnulib:
--- lib/stdlib.in.h.orig        Thu Nov 10 13:43:36 2011
+++ lib/stdlib.in.h     Thu Nov 10 12:41:37 2011
@@ -459,10 +459,19 @@
 /* Set the pathname of the pseudo-terminal slave associated with
    the master FD is open on and return 0, or set errno and return
    non-zero on errors.  */
-# if address@hidden@
+# if @REPLACE_PTSNAME_R@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef ptsname_r
+#   define ptsname_r rpl_ptsname_r
+#  endif
+_GL_FUNCDECL_RPL (ptsname_r, int, (int fd, char *buf, size_t len));
+_GL_CXXALIAS_RPL (ptsname_r, int, (int fd, char *buf, size_t len));
+# else
+#  if address@hidden@
 _GL_FUNCDECL_SYS (ptsname_r, int, (int fd, char *buf, size_t len));
-# endif
+#  endif
 _GL_CXXALIAS_SYS (ptsname_r, int, (int fd, char *buf, size_t len));
+# endif
 _GL_CXXALIASWARN (ptsname_r);
 #elif defined GNULIB_POSIXCHECK
 # undef ptsname_r
--- m4/ptsname_r.m4.orig        Thu Nov 10 13:43:36 2011
+++ m4/ptsname_r.m4     Thu Nov 10 13:34:27 2011
@@ -1,4 +1,4 @@
-# ptsname_r.m4 serial 1
+# ptsname_r.m4 serial 2
 dnl Copyright (C) 2010-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -14,6 +14,33 @@
   AC_CHECK_FUNCS_ONCE([ptsname_r])
   if test $ac_cv_func_ptsname_r = no; then
     HAVE_PTSNAME_R=0
+  else
+    dnl On OSF/1 5.1, the type of the third argument is 'int', not 'size_t',
+    dnl and the declaration is missing if _REENTRANT is not defined.
+    AC_CACHE_CHECK([whether ptsname_r has the same signature as in glibc],
+      [gl_cv_func_ptsname_r_signature_ok],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <stddef.h>
+              #include <stdlib.h>
+              /* Test whether ptsname_r is declared at all.  */
+              int (*f) (int, char *, size_t) = ptsname_r;
+              /* Test whether it has the same declaration as in glibc.  */
+              #undef ptsname_r
+              extern
+              #ifdef __cplusplus
+              "C"
+              #endif
+              int ptsname_r (int, char *, size_t);
+            ]],
+            [[return f (0, NULL, 0);]])
+         ],
+         [gl_cv_func_ptsname_r_signature_ok=yes],
+         [gl_cv_func_ptsname_r_signature_ok=no])
+      ])
+    if test $gl_cv_func_ptsname_r_signature_ok = no; then
+      REPLACE_PTSNAME_R=1
+    fi
   fi
 ])
 
--- m4/stdlib_h.m4.orig Thu Nov 10 13:43:36 2011
+++ m4/stdlib_h.m4      Thu Nov 10 12:42:08 2011
@@ -1,4 +1,4 @@
-# stdlib_h.m4 serial 38
+# stdlib_h.m4 serial 39
 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -99,6 +99,7 @@
   REPLACE_MALLOC=0;          AC_SUBST([REPLACE_MALLOC])
   REPLACE_MBTOWC=0;          AC_SUBST([REPLACE_MBTOWC])
   REPLACE_MKSTEMP=0;         AC_SUBST([REPLACE_MKSTEMP])
+  REPLACE_PTSNAME_R=0;       AC_SUBST([REPLACE_PTSNAME_R])
   REPLACE_PUTENV=0;          AC_SUBST([REPLACE_PUTENV])
   REPLACE_REALLOC=0;         AC_SUBST([REPLACE_REALLOC])
   REPLACE_REALPATH=0;        AC_SUBST([REPLACE_REALPATH])
--- modules/ptsname_r.orig      Thu Nov 10 13:43:36 2011
+++ modules/ptsname_r   Thu Nov 10 13:23:40 2011
@@ -8,11 +8,11 @@
 Depends-on:
 stdlib
 extensions
-ttyname_r       [test $HAVE_PTSNAME_R = 0]
+ttyname_r       [test $HAVE_PTSNAME_R = 0 || test $REPLACE_PTSNAME_R = 1]
 
 configure.ac:
 gl_FUNC_PTSNAME_R
-if test $HAVE_PTSNAME_R = 0; then
+if test $HAVE_PTSNAME_R = 0 || test $REPLACE_PTSNAME_R = 1; then
   AC_LIBOBJ([ptsname_r])
   gl_PREREQ_PTSNAME_R
 fi
--- modules/stdlib.orig Thu Nov 10 13:43:36 2011
+++ modules/stdlib      Thu Nov 10 12:42:32 2011
@@ -93,6 +93,7 @@
              -e 's|@''REPLACE_MALLOC''@|$(REPLACE_MALLOC)|g' \
              -e 's|@''REPLACE_MBTOWC''@|$(REPLACE_MBTOWC)|g' \
              -e 's|@''REPLACE_MKSTEMP''@|$(REPLACE_MKSTEMP)|g' \
+             -e 's|@''REPLACE_PTSNAME_R''@|$(REPLACE_PTSNAME_R)|g' \
              -e 's|@''REPLACE_PUTENV''@|$(REPLACE_PUTENV)|g' \
              -e 's|@''REPLACE_REALLOC''@|$(REPLACE_REALLOC)|g' \
              -e 's|@''REPLACE_REALPATH''@|$(REPLACE_REALPATH)|g' \

-- 
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