From 64ee0bacb33ac4112f353a0d0771ff4f497d8fe3 Mon Sep 17 00:00:00 2001 From: Bruno Haible Date: Mon, 26 Apr 2010 00:18:10 +0200 Subject: [PATCH] ttyname_r: Make it work on Solaris 10. --- ChangeLog | 11 +++++++++ doc/posix-functions/ttyname_r.texi | 4 +++ lib/ttyname_r.c | 30 +++++++++++++++++++---- m4/ttyname_r.m4 | 50 ++++++++++++++++++++++++++++++++++++-- modules/ttyname_r | 1 + 5 files changed, 89 insertions(+), 7 deletions(-) diff --git a/ChangeLog b/ChangeLog index 6260fd3f2..9cdd83a51 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,16 @@ 2010-04-25 Bruno Haible + ttyname_r: Make it work on Solaris 10. + * m4/ttyname_r.m4 (gl_FUNC_TTYNAME_R): Define HAVE_POSIXDECL_TTYNAME_R + if the system function has the POSIX declaration. Test whether the + function fails if the buffer is less than 128 bytes large. + * lib/ttyname_r.c (ttyname_r): Handle both possible declarations of the + system's ttyname_r function. Provide a reasonably large buffer. + * modules/ttyname_r (Depends-on): Add extensions. + * doc/posix-functions/ttyname_r.texi: Mention the Solaris problem. + +2010-04-25 Bruno Haible + Use the 'extensions' module for some more functions on Solaris. * doc/posix-functions/asctime_r.texi: Recommend to use the 'extensions' module. diff --git a/doc/posix-functions/ttyname_r.texi b/doc/posix-functions/ttyname_r.texi index 4780390e2..877e4b2f6 100644 --- a/doc/posix-functions/ttyname_r.texi +++ b/doc/posix-functions/ttyname_r.texi @@ -14,6 +14,10 @@ NetBSD 3.0, mingw, BeOS. @item This function has an incompatible declaration on some platforms: MacOS X 10.4, Solaris 10 (when @code{_POSIX_PTHREAD_SEMANTICS} is not defined). +@item +This function refuses to do anything when the output buffer is less than 128 +bytes large, on some platforms: +Solaris 10. @end itemize Portability problems not fixed by Gnulib: diff --git a/lib/ttyname_r.c b/lib/ttyname_r.c index d3e58eb21..5b59547ca 100644 --- a/lib/ttyname_r.c +++ b/lib/ttyname_r.c @@ -29,12 +29,31 @@ int ttyname_r (int fd, char *buf, size_t buflen) #undef ttyname_r { - /* When ttyname_r exists and works, use it. - But on Solaris 10, ttyname_r is broken: it returns NULL in situations - when ttyname finds the result. */ -#if HAVE_TTYNAME_R && !defined __sun + /* When ttyname_r exists, use it. */ +#if HAVE_TTYNAME_R /* This code is multithread-safe. */ - char *name = ttyname_r (fd, buf, buflen <= INT_MAX ? buflen : INT_MAX); + /* On Solaris, ttyname_r always fails if buflen < 128. So provide a buffer + that is large enough. */ + char largerbuf[512]; +# if HAVE_POSIXDECL_TTYNAME_R + int err = + (buflen < sizeof (largerbuf) + ? ttyname_r (fd, largerbuf, sizeof (largerbuf)) + : ttyname_r (fd, buf, buflen <= INT_MAX ? buflen : INT_MAX)); + if (err != 0) + return err; + if (buflen < sizeof (largerbuf)) + { + size_t namelen = strlen (largerbuf); + if (namelen > buflen) + return ERANGE; + memcpy (buf, largerbuf, namelen); + } +# else + char *name = + (buflen < sizeof (largerbuf) + ? ttyname_r (fd, largerbuf, sizeof (largerbuf)) + : ttyname_r (fd, buf, buflen <= INT_MAX ? buflen : INT_MAX)); if (name == NULL) return errno; if (name != buf) @@ -44,6 +63,7 @@ ttyname_r (int fd, char *buf, size_t buflen) return ERANGE; memmove (buf, name, namelen); } +# endif return 0; #elif HAVE_TTYNAME /* Note: This is not multithread-safe. */ diff --git a/m4/ttyname_r.m4 b/m4/ttyname_r.m4 index ce4737498..c41d8ba81 100644 --- a/m4/ttyname_r.m4 +++ b/m4/ttyname_r.m4 @@ -1,4 +1,4 @@ -# ttyname_r.m4 serial 2 +# ttyname_r.m4 serial 3 dnl Copyright (C) 2010 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -8,11 +8,16 @@ AC_DEFUN([gl_FUNC_TTYNAME_R], [ AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + dnl Persuade Solaris to provide the POSIX compliant declaration of + dnl ttyname_r(). + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_CHECK_FUNCS([ttyname_r]) if test $ac_cv_func_ttyname_r = no; then HAVE_TTYNAME_R=0 else - dnl On MacOS X 10.4 and Solaris 10 the return type is 'char *', not 'int'. + dnl On MacOS X 10.4 (and Solaris 10 without gl_USE_SYSTEM_EXTENSIONS) + dnl the return type is 'char *', not 'int'. AC_CACHE_CHECK([whether ttyname_r is compatible with its POSIX signature], [gl_cv_func_ttyname_r_posix], [AC_COMPILE_IFELSE( @@ -26,6 +31,47 @@ AC_DEFUN([gl_FUNC_TTYNAME_R], ]) if test $gl_cv_func_ttyname_r_posix = no; then REPLACE_TTYNAME_R=1 + else + AC_DEFINE([HAVE_POSIXDECL_TTYNAME_R], [1], + [Define if the ttyname_r function has a POSIX compliant declaration.]) + dnl On Solaris 10, both ttyname_r functions (the one with the non-POSIX + dnl declaration and the one with the POSIX declaration) refuse to do + dnl anything when the output buffer is less than 128 bytes large. + AC_REQUIRE([AC_CANONICAL_HOST]) + AC_CACHE_CHECK([whether ttyname_r works with small buffers], + [gl_cv_func_ttyname_r_works], + [ + dnl Initial guess, used when cross-compiling or when /dev/tty cannot + dnl be opened. +changequote(,)dnl + case "$host_os" in + # Guess no on Solaris. + solaris*) gl_cv_func_ttyname_r_works="guessing no" ;; + # Guess yes otherwise. + *) gl_cv_func_ttyname_r_works="guessing yes" ;; + esac +changequote([,])dnl + AC_TRY_RUN([ +#include +#include +int +main (void) +{ + int fd; + char buf[31]; /* use any size < 128 here */ + + fd = open ("/dev/tty", O_RDONLY); + if (fd < 0) + return 1; + if (ttyname_r (fd, buf, sizeof (buf)) != 0) + return 1; + return 0; +}], [gl_cv_func_ttyname_r_works=yes], [:], [:]) + ]) + case "$gl_cv_func_ttyname_r_works" in + *yes) ;; + *) REPLACE_TTYNAME_R=1 ;; + esac fi fi if test $HAVE_TTYNAME_R = 0 || test $REPLACE_TTYNAME_R = 1; then diff --git a/modules/ttyname_r b/modules/ttyname_r index 1e74839ef..8e79bf32c 100644 --- a/modules/ttyname_r +++ b/modules/ttyname_r @@ -7,6 +7,7 @@ m4/ttyname_r.m4 Depends-on: unistd +extensions configure.ac: gl_FUNC_TTYNAME_R -- 2.11.0