virsh fails to read files larger than BUFSIZ bytes

* src/util.c (fread_file_lim): Use VIR_REALLOC_N, not VIR_ALLOC_N.
Bug introduced in 895d0fdf5b.
* tests/Makefile.am (test_scripts): Add read-bufsiz.
* tests/read-bufsiz: New test for the above.

tests/Makefile.am

@@ -47,6 +47,7 @@ noinst_PROGRAMS = xmlrpctest xml2sexprtest sexpr2xmltest virshtest conftest \
 test_scripts = \
 	daemon-conf \
 	int-overflow \
+	read-bufsiz \
 	read-non-seekable \
 	vcpupin
 

tests/read-bufsiz

@@ -0,0 +1,43 @@
+#!/bin/sh
+# ensure that reading a file larger than BUFSIZ works
+
+# Copyright (C) 2008 Free Software Foundation, Inc.
+
+# 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 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, see <http://www.gnu.org/licenses/>.
+
+if test "$VERBOSE" = yes; then
+  set -x
+  virsh --version
+fi
+
+. $srcdir/test-lib.sh
+
+fail=0
+
+# Output a valid definition, to be used as input.
+virsh -c test:///default dumpxml 1 > xml || fail=1
+
+for i in before after; do
+  # The largest BUFSIZ I've seen is 128K.  This is slightly larger.
+  printf %132000s ' ' > sp || fail=1
+  in=in-$i
+  # Append or prepend enough spaces to push the size over the limit:
+  ( test $i = before && cat sp xml || cat xml sp ) > $in || fail=1
+
+  virsh --connect test:///default define $in > out || fail=1
+  printf "Domain test defined from $in\n\n" > exp || fail=1
+  compare out exp || fail=1
+done
+
+(exit $fail); exit $fail