Check the return value of libc's functions to make `_FORTIFY_SOURCE=2' work.

This fixes bug #24009 reported by Martin Pitt.

* libguile/threads.c (guilify_self_1): Check the return value of
  pipe(2).
  (scm_std_select): Use `full_read ()' instead of `read ()' when reading
  from WAKEUP_FD.

* libguile/async.c (scm_i_queue_async_cell): Use `full_write ()' instead
  of write(2) when writing to SLEEP_FD.

* libguile/fports.c (fport_flush): Likewise.

* libguile/posix.c (getgroups): Use the return value of getgroups(2) as
  NGROUPS.
  (scm_nice): Get the return value of nice(2) to make glibc happy.

* libguile/scmsigs.c (take_signal): Use `full_write ()' instead of
  write(2).

libguile/async.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002, 2004, 2006 Free Software Foundation, Inc.
+/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002, 2004, 2006, 2008 Free Software Foundation, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -41,6 +41,8 @@
 #include <unistd.h>
 #endif
 
+#include <full-write.h>
+
 
 /* {Asynchronous Events}
  *
@@ -241,13 +243,13 @@ scm_i_queue_async_cell (SCM c, scm_i_thread *t)
   if (sleep_fd >= 0)
     {
       char dummy = 0;
+
       /* Likewise, T might already been done with sleeping here, but
 	 interrupting it once too often does no harm.  T might also
 	 not yet have started sleeping, but this is no problem either
 	 since the data written to a pipe will not be lost, unlike a
-	 condition variable signal.
-      */
-      write (sleep_fd, &dummy, 1);
+	 condition variable signal.  */
+      full_write (sleep_fd, &dummy, 1);
     }
 
   /* This is needed to protect sleep_mutex.

libguile/fports.c

@@ -59,6 +59,8 @@
 # include <winsock2.h>
 #endif /* __MINGW32__ */
 
+#include <full-write.h>
+
 /* Mingw (version 3.4.5, circa 2006) has ftruncate as an alias for chsize
    already, but have this code here in case that wasn't so in past versions,
    or perhaps to help other minimal DOS environments.
@@ -826,9 +828,9 @@ fport_flush (SCM port)
 	      const char *msg = "Error: could not flush file-descriptor ";
 	      char buf[11];
 
-	      write (2, msg, strlen (msg));
+	      full_write (2, msg, strlen (msg));
 	      sprintf (buf, "%d\n", fp->fdes);
-	      write (2, buf, strlen (buf));
+	      full_write (2, buf, strlen (buf));
 
 	      count = remaining;
 	    }

libguile/posix.c

@@ -277,7 +277,7 @@ SCM_DEFINE (scm_getgroups, "getgroups", 0, 0, 0,
 
   size = ngroups * sizeof (GETGROUPS_T);
   groups = scm_malloc (size);
-  getgroups (ngroups, groups);
+  ngroups = getgroups (ngroups, groups);
 
   result = scm_c_make_vector (ngroups, SCM_BOOL_F);
   while (--ngroups >= 0) 
@@ -1563,12 +1563,15 @@ SCM_DEFINE (scm_nice, "nice", 1, 0, 0,
 	    "The return value is unspecified.")
 #define FUNC_NAME s_scm_nice
 {
+  int nice_value;
+
   /* nice() returns "prio-NZERO" on success or -1 on error, but -1 can arise
      from "prio-NZERO", so an error must be detected from errno changed */
   errno = 0;
-  nice (scm_to_int (incr));
+  nice_value = nice (scm_to_int (incr));
   if (errno != 0)
     SCM_SYSERROR;
+
   return SCM_UNSPECIFIED;
 }
 #undef FUNC_NAME

libguile/scmsigs.c

@@ -63,6 +63,9 @@
 #define pipe(fd) _pipe (fd, 256, O_BINARY)
 #endif
 
+#include <full-write.h>
+
+
 
 
 /* SIGRETTYPE is the type that signal handlers return.  See <signal.h> */
@@ -137,7 +140,7 @@ static SIGRETTYPE
 take_signal (int signum)
 {
   char sigbyte = signum;
-  write (signal_pipe[1], &sigbyte, 1);
+  full_write (signal_pipe[1], &sigbyte, 1);
 
 #ifndef HAVE_SIGACTION
   signal (signum, take_signal);

libguile/threads.c

@@ -61,6 +61,9 @@
 # define pipe(fd) _pipe (fd, 256, O_BINARY)
 #endif /* __MINGW32__ */
 
+#include <full-read.h>
+
+
 static void
 to_timespec (SCM t, scm_t_timespec *waittime)
 {
@@ -480,8 +483,13 @@ guilify_self_1 (SCM_STACKITEM *base)
   t->sleep_mutex = NULL;
   t->sleep_object = SCM_BOOL_F;
   t->sleep_fd = -1;
-  /* XXX - check for errors. */
-  pipe (t->sleep_pipe);
+
+  if (pipe (t->sleep_pipe) != 0)
+    /* FIXME: Error conditions during the initialization phase are handled
+       gracelessly since public functions such as `scm_init_guile ()'
+       currently have type `void'.  */
+    abort ();
+
   scm_i_pthread_mutex_init (&t->heap_mutex, NULL);
   scm_i_pthread_mutex_init (&t->admin_mutex, NULL);
   t->clear_freelists_p = 0;
@@ -1776,7 +1784,8 @@ scm_std_select (int nfds,
   if (res > 0 && FD_ISSET (wakeup_fd, readfds))
     {
       char dummy;
-      read (wakeup_fd, &dummy, 1);
+      full_read (wakeup_fd, &dummy, 1);
+
       FD_CLR (wakeup_fd, readfds);
       res -= 1;
       if (res == 0)