From d18147940f8e330881681c7ef68505ac4463e652 Mon Sep 17 00:00:00 2001 From: "Daniel P. Berrange" Date: Fri, 21 Dec 2012 13:15:19 +0000 Subject: Introduce an LXC specific public API & library This patch introduces support for LXC specific public APIs. In common with what was done for QEMU, this creates a libvirt_lxc.so library and libvirt/libvirt-lxc.h header file. The actual APIs are int virDomainLxcOpenNamespace(virDomainPtr domain, int **fdlist, unsigned int flags); int virDomainLxcEnterNamespace(virDomainPtr domain, unsigned int nfdlist, int *fdlist, unsigned int *noldfdlist, int **oldfdlist, unsigned int flags); which provide a way to use the setns() system call to move the calling process into the container's namespace. It is not practical to write in a generically applicable manner. The nearest that we could get to such an API would be an API which allows to pass a command + argv to be executed inside a container. Even if we had such a generic API, this LXC specific API is still useful, because it allows the caller to maintain the current process context, in particular any I/O streams they have open. NB the virDomainLxcEnterNamespace() API is special in that it runs client side, so does not involve the internal driver API. Signed-off-by: Daniel P. Berrange --- libvirt-lxc-override.c | 141 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 141 insertions(+) create mode 100644 libvirt-lxc-override.c (limited to 'libvirt-lxc-override.c') diff --git a/libvirt-lxc-override.c b/libvirt-lxc-override.c new file mode 100644 index 0000000..c80668e --- /dev/null +++ b/libvirt-lxc-override.c @@ -0,0 +1,141 @@ +/* + * libvir.c: this modules implements the main part of the glue of the + * libvir library and the Python interpreter. It provides the + * entry points where an automatically generated stub is + * unpractical + * + * Copyright (C) 2012-2013 Red Hat, Inc. + * + * Daniel Veillard + */ + +#include + +/* Horrible kludge to work around even more horrible name-space pollution + via Python.h. That file includes /usr/include/python2.5/pyconfig*.h, + which has over 180 autoconf-style HAVE_* definitions. Shame on them. */ +#undef HAVE_PTHREAD_H + +#include +#include "libvirt/libvirt-lxc.h" +#include "libvirt/virterror.h" +#include "typewrappers.h" +#include "libvirt-lxc.h" +#include "viralloc.h" +#include "virfile.h" + +#ifndef __CYGWIN__ +extern void initlibvirtmod_lxc(void); +#else +extern void initcygvirtmod_lxc(void); +#endif + +#if 0 +# define DEBUG_ERROR 1 +#endif + +#if DEBUG_ERROR +# define DEBUG(fmt, ...) \ + printf(fmt, __VA_ARGS__) +#else +# define DEBUG(fmt, ...) \ + do {} while (0) +#endif + +/* The two-statement sequence "Py_INCREF(Py_None); return Py_None;" + is so common that we encapsulate it here. Now, each use is simply + return VIR_PY_NONE; */ +#define VIR_PY_NONE (Py_INCREF (Py_None), Py_None) +#define VIR_PY_INT_FAIL (libvirt_intWrap(-1)) +#define VIR_PY_INT_SUCCESS (libvirt_intWrap(0)) + +/************************************************************************ + * * + * Statistics * + * * + ************************************************************************/ + +static PyObject * +libvirt_lxc_virDomainLxcOpenNamespace(PyObject *self ATTRIBUTE_UNUSED, + PyObject *args) { + PyObject *py_retval; + virDomainPtr domain; + PyObject *pyobj_domain; + unsigned int flags; + int c_retval; + int *fdlist = NULL; + int i; + + if (!PyArg_ParseTuple(args, (char *)"Oi:virDomainLxcOpenNamespace", + &pyobj_domain, &flags)) + return NULL; + domain = (virDomainPtr) PyvirDomain_Get(pyobj_domain); + + if (domain == NULL) + return VIR_PY_NONE; + LIBVIRT_BEGIN_ALLOW_THREADS; + c_retval = virDomainLxcOpenNamespace(domain, &fdlist, flags); + LIBVIRT_END_ALLOW_THREADS; + + if (c_retval < 0) + return VIR_PY_NONE; + + py_retval = PyList_New(c_retval); + for (i = 0 ; i < c_retval ; i++) { + PyObject *item = NULL; + + if ((item = PyInt_FromLong(fdlist[i])) == NULL) + goto error; + + if (PyList_Append(py_retval, item) < 0) { + Py_DECREF(item); + goto error; + } + } + return py_retval; + +error: + for (i = 0 ; i < c_retval ; i++) { + VIR_FORCE_CLOSE(fdlist[i]); + } + VIR_FREE(fdlist); + return VIR_PY_NONE; +} +/************************************************************************ + * * + * The registration stuff * + * * + ************************************************************************/ +static PyMethodDef libvirtLxcMethods[] = { +#include "libvirt-lxc-export.c" + {(char *) "virDomainLxcOpenNamespace", libvirt_lxc_virDomainLxcOpenNamespace, METH_VARARGS, NULL}, + {NULL, NULL, 0, NULL} +}; + +void +#ifndef __CYGWIN__ +initlibvirtmod_lxc +#else +initcygvirtmod_lxc +#endif + (void) +{ + static int initialized = 0; + + if (initialized != 0) + return; + + if (virInitialize() < 0) + return; + + /* initialize the python extension module */ + Py_InitModule((char *) +#ifndef __CYGWIN__ + "libvirtmod_lxc" +#else + "cygvirtmod_lxc" +#endif + , libvirtLxcMethods); + + initialized = 1; +} -- cgit v1.2.1