getloadavg: use libperfstat on AIX5

[gnulib.git] / lib / fpurge.c

diff --git a/lib/fpurge.c b/lib/fpurge.c
index c4572fa..cc230fb 100644 (file)
--- a/lib/fpurge.c
+++ b/lib/fpurge.c
@@ -1,48 +1,121 @@
 /* Flushing buffers of a FILE stream.
    Copyright (C) 2007 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
-   You should have received a copy of the GNU General Public License along
-   with this program; if not, write to the Free Software Foundation,
-   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 
 /* Specification.  */
 #include "fpurge.h"
 
+#if HAVE___FPURGE                   /* glibc >= 2.2, Solaris >= 7 */
+# include <stdio_ext.h>
+#endif
+#include <stdlib.h>
+
 int
 fpurge (FILE *fp)
 {
+#if HAVE___FPURGE                   /* glibc >= 2.2, Solaris >= 7 */
+
+  __fpurge (fp);
+  /* The __fpurge function does not have a return value.  */
+  return 0;
+
+#elif HAVE_FPURGE                   /* FreeBSD, NetBSD, OpenBSD, MacOS X */
+
+  /* Call the system's fpurge function.  */
+# undef fpurge
+# if !HAVE_DECL_FPURGE
+  extern int fpurge (FILE *);
+# endif
+  int result = fpurge (fp);
+# if defined __sferror              /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
+  if (result == 0)
+    /* Correct the invariants that fpurge broke.
+       <stdio.h> on BSD systems says:
+         "The following always hold: if _flags & __SRD, _w is 0."
+       If this invariant is not fulfilled and the stream is read-write but
+       currently writing, subsequent putc or fputc calls will write directly
+       into the buffer, although they shouldn't be allowed to.  */
+    if ((fp->_flags & __SRD) != 0)
+      fp->_w = 0;
+# endif
+  return result;
+
+#else
+
   /* Most systems provide FILE as a struct and the necessary bitmask in
      <stdio.h>, because they need it for implementing getc() and putc() as
      fast macros.  */
-#if defined _IO_ferror_unlocked     /* GNU libc, BeOS */
+# if defined _IO_ferror_unlocked    /* GNU libc, BeOS */
   fp->_IO_read_end = fp->_IO_read_ptr;
   fp->_IO_write_ptr = fp->_IO_write_base;
+  /* Avoid memory leak when there is an active ungetc buffer.  */
+  if (fp->_IO_save_base != NULL)
+    {
+      free (fp->_IO_save_base);
+      fp->_IO_save_base = NULL;
+    }
   return 0;
-#elif defined __sferror             /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
+# elif defined __sferror            /* FreeBSD, NetBSD, OpenBSD, MacOS X, Cygwin */
   fp->_p = fp->_bf._base;
   fp->_r = 0;
-  fp->_w = ((fp->_flags & (__SLBF | __SNBF)) == 0 /* fully buffered? */
+  fp->_w = ((fp->_flags & (__SLBF | __SNBF | __SRD)) == 0 /* fully buffered and not currently reading? */
            ? fp->_bf._size
            : 0);
+  /* Avoid memory leak when there is an active ungetc buffer.  */
+#  if defined __NetBSD__ || defined __OpenBSD__ /* NetBSD, OpenBSD */
+   /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
+      and <http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> */
+#   define fp_ub ((struct { struct __sbuf _ub; } *) fp->_ext._base)->_ub
+#  else                                         /* FreeBSD, MacOS X, Cygwin */
+#   define fp_ub fp->_ub
+#  endif
+  if (fp_ub._base != NULL)
+    {
+      if (fp_ub._base != fp->_ubuf)
+       free (fp_ub._base);
+      fp_ub._base = NULL;
+    }
   return 0;
-#elif defined _IOERR                /* AIX, HP-UX, IRIX, OSF/1, Solaris, mingw */
+# elif defined _IOERR               /* AIX, HP-UX, IRIX, OSF/1, Solaris, mingw */
   fp->_ptr = fp->_base;
   if (fp->_ptr != NULL)
     fp->_cnt = 0;
   return 0;
-#else
- #error "Please port gnulib fpurge.c to your platform!"
+# elif defined __UCLIBC__           /* uClibc */
+#  ifdef __STDIO_BUFFERS
+  if (fp->__modeflags & __FLAG_WRITING)
+    fp->__bufpos = fp->__bufstart;
+  else if (fp->__modeflags & (__FLAG_READONLY | __FLAG_READING))
+    fp->__bufpos = fp->__bufread;
+#  endif
+  return 0;
+# elif defined __QNX__              /* QNX */
+  fp->_Rback = fp->_Back + sizeof (fp->_Back);
+  fp->_Rsave = NULL;
+  if (fp->_Mode & 0x2000 /* _MWRITE */)
+    /* fp->_Buf <= fp->_Next <= fp->_Wend */
+    fp->_Next = fp->_Buf;
+  else
+    /* fp->_Buf <= fp->_Next <= fp->_Rend */
+    fp->_Rend = fp->_Next;
+  return 0;
+# else
+ #error "Please port gnulib fpurge.c to your platform! Look at the definitions of fflush, setvbuf and ungetc on your system, then report this to bug-gnulib."
+# endif
+
 #endif
 }