ruby: Translate C examples into Ruby and include documentation.

5 files changed, 231 insertions, 0 deletions

diff --git a/ruby/examples/LICENSE b/ruby/examples/LICENSE
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+++ b/ruby/examples/LICENSE
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+All the examples in the 'ruby/examples' subdirectory may be freely
+copied, modified and distributed without any restrictions.
diff --git a/ruby/examples/Makefile.am b/ruby/examples/Makefile.am
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+++ b/ruby/examples/Makefile.am
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+# libguestfs Ruby examples
+# Copyright (C) 2010 Red Hat 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 2 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+EXTRA_DIST = \
+	LICENSE \
+	create_disk.rb \
+	inspect_vm.rb \
+	guestfs-ruby.pod
+
+CLEANFILES = stamp-guestfs-ruby.pod
+
+man_MANS = guestfs-ruby.3
+noinst_DATA = $(top_builddir)/html/guestfs-ruby.3.html
+
+guestfs-ruby.3 $(top_builddir)/html/guestfs-ruby.3.html: stamp-guestfs-ruby.pod
+
+stamp-guestfs-ruby.pod: guestfs-ruby.pod create_disk.rb inspect_vm.rb
+	$(top_srcdir)/podwrapper.sh \
+	  --section 3 \
+	  --man guestfs-ruby.3 \
+	  --html $(top_builddir)/html/guestfs-ruby.3.html \
+	  --verbatim create_disk.rb:@EXAMPLE1@ \
+	  --verbatim inspect_vm.rb:@EXAMPLE2@ \
+	  $<
+	touch $@
diff --git a/ruby/examples/create_disk.rb b/ruby/examples/create_disk.rb
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+++ b/ruby/examples/create_disk.rb
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+# Example showing how to create a disk image.
+
+require 'guestfs'
+
+output = "disk.img"
+
+g = Guestfs::Guestfs.new()
+
+# Create a raw-format sparse disk image, 512 MB in size.
+File.open(output, "w") {
+  |f| f.truncate(512 * 1024 * 1024)
+}
+
+# Set the trace flag so that we can see each libguestfs call.
+g.set_trace(1)
+
+# Set the autosync flag so that the disk will be synchronized
+# automatically when the libguestfs handle is closed.
+g.set_autosync(1)
+
+# Attach the disk image to libguestfs.
+g.add_drive_opts(output, :format => "raw")
+
+# Run the libguestfs back-end.
+g.launch();
+
+# Get the list of devices.  Because we only added one drive
+# above, we expect that this list should contain a single
+# element.
+devices = g.list_devices()
+if devices.length != 1 then
+  raise "error: expected a single device from list-devices"
+end
+
+# Partition the disk as one single MBR partition.
+g.part_disk(devices[0], "mbr")
+
+# Get the list of partitions.  We expect a single element, which
+# is the partition we have just created.
+partitions = g.list_partitions()
+if partitions.length != 1 then
+  raise "error: expected a single partition from list-partitions"
+end
+
+# Create a filesystem on the partition.
+g.mkfs("ext4", partitions[0])
+
+# Now mount the filesystem so that we can add files.
+g.mount_options("", partitions[0], "/")
+
+# Create some files and directories.
+g.touch("/empty")
+message = "Hello, world\n"
+g.write("/hello", message)
+g.mkdir("/foo")
+
+# This one uploads the local file /etc/resolv.conf into
+# the disk image.
+g.upload("/etc/resolv.conf", "/foo/resolv.conf")
+
+# Because 'autosync' was set (above) we can just close the handle
+# and the disk contents will be synchronized.  You can also do
+# this manually by calling g#umount_all and g#sync.
+g.close()
diff --git a/ruby/examples/guestfs-ruby.pod b/ruby/examples/guestfs-ruby.pod
new file mode 100644
index 00000000..d3ce9287
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+++ b/ruby/examples/guestfs-ruby.pod
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+=encoding utf8
+
+=head1 NAME
+
+guestfs-ruby - How to use libguestfs from Ruby
+
+=head1 SYNOPSIS
+
+ require 'guestfs'
+ g = Guestfs::Guestfs.new()
+ g.add_drive_opts("disk.img",
+                  :readonly => 1, :format => "raw")
+ g.launch()
+
+=head1 DESCRIPTION
+
+This manual page documents how to call libguestfs from the Ruby
+programming language.  This page just documents the differences from
+the C API and gives some examples.  If you are not familiar with using
+libguestfs, you also need to read L<guestfs(3)>.
+
+=head2 EXCEPTIONS
+
+Errors from libguestfs functions are mapped into the C<Error>
+exception.  This has a single parameter which is the error message (a
+string).
+
+=head1 EXAMPLE 1: CREATE A DISK IMAGE
+
+@EXAMPLE1@
+
+=head1 EXAMPLE 2: INSPECT A VIRTUAL MACHINE DISK IMAGE
+
+@EXAMPLE2@
+
+=head1 SEE ALSO
+
+L<guestfs(3)>,
+L<guestfs-examples(3)>,
+L<guestfs-ocaml(3)>,
+L<guestfs-python(3)>,
+L<http://libguestfs.org/>.
+
+=head1 AUTHORS
+
+Richard W.M. Jones (C<rjones at redhat dot com>)
+
+=head1 COPYRIGHT
+
+Copyright (C) 2010 Red Hat Inc. L<http://libguestfs.org/>
+
+The examples in this manual page may be freely copied, modified and
+distributed without any restrictions.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+This library 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
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
diff --git a/ruby/examples/inspect_vm.rb b/ruby/examples/inspect_vm.rb
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+++ b/ruby/examples/inspect_vm.rb
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+# Example showing how to inspect a virtual machine disk.
+
+require 'guestfs'
+
+if ARGV.length == 0
+  puts "usage: inspect_vm disk.img"
+  exit 1
+end
+disk = ARGV[0]
+
+g = Guestfs::Guestfs.new()
+
+# Attach the disk image read-only to libguestfs.
+g.add_drive_opts(disk, :readonly => 1)
+
+# Run the libguestfs back-end.
+g.launch()
+
+# Ask libguestfs to inspect for operating systems.
+roots = g.inspect_os()
+if roots.length == 0
+  puts "inspect_vm: no operating systems found"
+  exit 1
+end
+
+for root in roots do
+  printf("Root device: %s\n", root)
+
+  # Print basic information about the operating system.
+  printf("  Product name: %s\n", g.inspect_get_product_name(root))
+  printf("  Version:      %d.%d\n",
+         g.inspect_get_major_version(root),
+         g.inspect_get_minor_version(root))
+  printf("  Type:         %s\n", g.inspect_get_type(root))
+  printf("  Distro:       %s\n", g.inspect_get_distro(root))
+
+  # Mount up the disks, like guestfish -i.
+  #
+  # Sort keys by length, shortest first, so that we end up
+  # mounting the filesystems in the correct order.
+  mps = g.inspect_get_mountpoints(root)
+  mps = mps.sort {|a,b| a[0].length <=> b[0].length}
+  for mp in mps do
+    g.mount_ro(mp[1], mp[0])
+  end
+
+  # If /etc/issue.net file exists, print up to 3 lines.
+  filename = "/etc/issue.net"
+  if g.is_file filename then
+    printf("--- %s ---\n", filename)
+    lines = g.head_n(3, filename)
+    for line in lines do
+      puts line
+    end
+  end
+
+  # Unmount everything.
+  g.umount_all()
+end