diff options
| -rw-r--r-- | configure.ac | 10 | ||||
| -rwxr-xr-x | tests/features/glupy.t | 29 | ||||
| -rw-r--r-- | xlators/features/Makefile.am | 2 | ||||
| -rw-r--r-- | xlators/features/glupy/Makefile.am | 3 | ||||
| -rw-r--r-- | xlators/features/glupy/doc/README.md | 44 | ||||
| -rw-r--r-- | xlators/features/glupy/src/Makefile.am | 20 | ||||
| -rw-r--r-- | xlators/features/glupy/src/glupy.c | 405 | ||||
| -rw-r--r-- | xlators/features/glupy/src/glupy.h | 47 | ||||
| -rw-r--r-- | xlators/features/glupy/src/gluster.py | 118 | ||||
| -rw-r--r-- | xlators/features/glupy/src/helloworld.py | 19 | ||||
| -rw-r--r-- | xlators/features/glupy/src/negative.py | 93 |
11 files changed, 789 insertions, 1 deletions
diff --git a/configure.ac b/configure.ac index 6357b19fa8a..48237bc4001 100644 --- a/configure.ac +++ b/configure.ac @@ -95,6 +95,8 @@ AC_CONFIG_FILES([Makefile xlators/protocol/server/Makefile xlators/protocol/server/src/Makefile xlators/features/Makefile + xlators/features/glupy/Makefile + xlators/features/glupy/src/Makefile xlators/features/locks/Makefile xlators/features/locks/src/Makefile xlators/features/quota/Makefile @@ -632,6 +634,14 @@ if test "x$LIBAIO" != "x"; then fi +BUILD_GLUPY=no +AC_CHECK_LIB([python2.6],[PyImport_Import],[BUILD_GLUPY=yes]) + +if test "x$BUILD_GLUPY" = "xyes"; then + GLUPY_SUBDIR=glupy +fi +AC_SUBST(GLUPY_SUBDIR) + AC_SUBST(GF_HOST_OS) AC_SUBST([GF_GLUSTERFS_LIBS]) AC_SUBST(GF_GLUSTERFS_CFLAGS) diff --git a/tests/features/glupy.t b/tests/features/glupy.t new file mode 100755 index 00000000000..49bf11df516 --- /dev/null +++ b/tests/features/glupy.t @@ -0,0 +1,29 @@ +#!/bin/bash + +. $(dirname $0)/../include.rc + +cleanup; + +TEST mkdir -p $B0/glupytest +cat > $B0/glupytest.vol <<EOF +volume vol-posix + type storage/posix + option directory $B0/glupytest +end-volume + +volume vol-glupy + type features/glupy + option module-name helloworld + subvolumes vol-posix +end-volume +EOF + +TEST glusterfs -f $B0/glupytest.vol $M0; + +TEST touch $M0/filename; +EXPECT "filename" ls $M0 +TEST rm -f $M0/filename; + +TEST umount -l $M0; + +cleanup; diff --git a/xlators/features/Makefile.am b/xlators/features/Makefile.am index 09aab1293f0..6a73301d74e 100644 --- a/xlators/features/Makefile.am +++ b/xlators/features/Makefile.am @@ -1,4 +1,4 @@ SUBDIRS = locks quota read-only mac-compat quiesce marker index \ - protect # trash path-converter # filter + protect $(GLUPY_SUBDIR) # trash path-converter # filter CLEANFILES = diff --git a/xlators/features/glupy/Makefile.am b/xlators/features/glupy/Makefile.am new file mode 100644 index 00000000000..a985f42a877 --- /dev/null +++ b/xlators/features/glupy/Makefile.am @@ -0,0 +1,3 @@ +SUBDIRS = src + +CLEANFILES = diff --git a/xlators/features/glupy/doc/README.md b/xlators/features/glupy/doc/README.md new file mode 100644 index 00000000000..2d7b30ef694 --- /dev/null +++ b/xlators/features/glupy/doc/README.md @@ -0,0 +1,44 @@ +This is just the very start for a GlusterFS[1] meta-translator that will +allow translator code to be written in Python. It's based on the standard +Python embedding (not extending) techniques, plus a dash of the ctypes module. +The interface is a pretty minimal adaptation of the dispatches and callbacks +from the C API[2] to Python, as follows: + +* Dispatch functions and callbacks must be defined on an "xlator" class + derived from gluster.Translator so that they'll be auto-registered with + the C translator during initialization. + +* For each dispatch or callback function you want to intercept, you define a + Python function using the xxx\_fop\_t or xxx\_cbk\_t decorator. + +* The arguments for each operation are different, so you'll need to refer to + the C API. GlusterFS-specific types are used (though only loc\_t is fully + defined so far) and type correctness is enforced by ctypes. + +* If you do intercept a dispatch function, it is your responsibility to call + xxx\_wind (like STACK\_WIND in the C API but operation-specific) to pass + the request to the next translator. If you do not intercept a function, it + will default the same way as for C (pass through to the same operation with + the same arguments on the first child translator). + +* If you intercept a callback function, it is your responsibility to call + xxx\_unwind (like STACK\_UNWIND\_STRICT in the C API) to pass the request back + to the caller. + +So far only the lookup and create operations are handled this way, to support +the "negative lookup" example. Now that the basic infrastructure is in place, +adding more functions should be very quick, though with that much boilerplate I +might pause to write a code generator. I also plan to add structure +definitions and interfaces for some of the utility functions in libglusterfs +(especially those having to do with inode and fd context) in the fairly near +future. Note that you can also use ctypes to get at anything not explicitly +exposed to Python already. + +_If you're coming here because of the Linux Journal article, please note that +the code has evolved since that was written. The version that matches the +article is here:_ + +https://github.com/jdarcy/glupy/tree/4bbae91ba459ea46ef32f2966562492e4ca9187a + +[1] http://www.gluster.org +[2] http://hekafs.org/dist/xlator_api_2.html diff --git a/xlators/features/glupy/src/Makefile.am b/xlators/features/glupy/src/Makefile.am new file mode 100644 index 00000000000..ccecc7a4ff1 --- /dev/null +++ b/xlators/features/glupy/src/Makefile.am @@ -0,0 +1,20 @@ +xlator_LTLIBRARIES = glupy.la + +xlatordir = $(libdir)/glusterfs/$(PACKAGE_VERSION)/xlator/features + +glupydir = $(xlatordir)/glupy + +glupy_PYTHON = gluster.py negative.py helloworld.py + +glupy_la_LDFLAGS = -module -avoid-version -shared -nostartfiles +glupy_la_SOURCES = glupy.c +glupy_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la \ + -lpthread -lpython2.6 + +noinst_HEADERS = glupy.h + +AM_CPPFLAGS = $(GF_CPPFLAGS) -I$(top_srcdir)/libglusterfs/src + +AM_CFLAGS = -Wall -fno-strict-aliasing -DGLUSTER_PYTHON_PATH=\"$(glupydir)\" $(GF_CFLAGS) + +CLEANFILES = diff --git a/xlators/features/glupy/src/glupy.c b/xlators/features/glupy/src/glupy.c new file mode 100644 index 00000000000..9c06085b938 --- /dev/null +++ b/xlators/features/glupy/src/glupy.c @@ -0,0 +1,405 @@ +/* + Copyright (c) 2012 Red Hat, Inc. <http://www.redhat.com> + This file is part of GlusterFS. + + GlusterFS 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. + + GlusterFS 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/>. +*/ + +#include <ctype.h> +#include <sys/uio.h> +#include <python2.6/Python.h> + +#ifndef _CONFIG_H +#define _CONFIG_H +#include "config.h" +#endif + +#include "glusterfs.h" +#include "xlator.h" +#include "logging.h" +#include "defaults.h" + +#include "glupy.h" + +/* UTILITY FUNCTIONS FOR FOP-SPECIFIC CODE */ + +pthread_key_t gil_init_key; + +PyGILState_STATE +glupy_enter (void) +{ +#if 0 + if (!pthread_getspecific(gil_init_key)) { + PyEval_ReleaseLock(); + (void)pthread_setspecific(gil_init_key,(void *)1); + } +#endif + + return PyGILState_Ensure(); +} + +void +glupy_leave (PyGILState_STATE gstate) +{ + PyGILState_Release(gstate); +} + +/* FOP: LOOKUP */ + +int32_t +glupy_lookup_cbk (call_frame_t *frame, void *cookie, xlator_t *this, + int32_t op_ret, int32_t op_errno, inode_t *inode, + struct iatt *buf, dict_t *xdata, struct iatt *postparent) +{ + glupy_private_t *priv = this->private; + PyGILState_STATE gstate; + int32_t ret; + + if (!priv->cbks[GLUPY_LOOKUP]) { + goto unwind; + } + + gstate = glupy_enter(); + ret = ((fop_lookup_cbk_t)(priv->cbks[GLUPY_LOOKUP]))( + frame, cookie, this, op_ret, op_errno, + inode, buf, xdata, postparent); + glupy_leave(gstate); + + return ret; + +unwind: + frame->local = NULL; + STACK_UNWIND_STRICT (lookup, frame, op_ret, op_errno, inode, buf, + xdata, postparent); + return 0; +} + +int32_t +glupy_lookup (call_frame_t *frame, xlator_t *this, loc_t *loc, + dict_t *xdata) +{ + glupy_private_t *priv = this->private; + PyGILState_STATE gstate; + int32_t ret; + static long next_id = 0; + + if (!priv->fops[GLUPY_LOOKUP]) { + goto wind; + } + + gstate = glupy_enter(); + frame->local = (void *)++next_id; + ret = ((fop_lookup_t)(priv->fops[GLUPY_LOOKUP]))( + frame, this, loc, xdata); + glupy_leave(gstate); + + return ret; + +wind: + STACK_WIND (frame, glupy_lookup_cbk, FIRST_CHILD(this), + FIRST_CHILD(this)->fops->lookup, loc, xdata); + return 0; +} + +void +wind_lookup (call_frame_t *frame, xlator_t *xl, loc_t *loc, dict_t *xdata) +{ + + xlator_t *this = THIS; + + if (!xl || (xl == this)) { + xl = FIRST_CHILD(this); + } + + STACK_WIND(frame,glupy_lookup_cbk,xl,xl->fops->lookup,loc,xdata); +} + +void +unwind_lookup (call_frame_t *frame, long cookie, xlator_t *this, + int32_t op_ret, int32_t op_errno, inode_t *inode, + struct iatt *buf, dict_t *xdata, struct iatt *postparent) +{ + frame->local = NULL; + STACK_UNWIND_STRICT(lookup,frame,op_ret,op_errno, + inode,buf,xdata,postparent); +} + +void +set_lookup_fop (long py_this, fop_lookup_t fop) +{ + glupy_private_t *priv = ((xlator_t *)py_this)->private; + + priv->fops[GLUPY_LOOKUP] = (long)fop; +} + +void +set_lookup_cbk (long py_this, fop_lookup_cbk_t cbk) +{ + glupy_private_t *priv = ((xlator_t *)py_this)->private; + + priv->cbks[GLUPY_LOOKUP] = (long)cbk; +} + +/* FOP: CREATE */ + +int32_t +glupy_create_cbk (call_frame_t *frame, void *cookie, xlator_t *this, + int32_t op_ret, int32_t op_errno, fd_t *fd, inode_t *inode, + struct iatt *buf, struct iatt *preparent, + struct iatt *postparent, dict_t *xdata) +{ + glupy_private_t *priv = this->private; + PyGILState_STATE gstate; + int32_t ret; + + if (!priv->cbks[GLUPY_CREATE]) { + goto unwind; + } + + gstate = glupy_enter(); + ret = ((fop_create_cbk_t)(priv->cbks[GLUPY_CREATE]))( + frame, cookie, this, op_ret, op_errno, + fd, inode, buf, preparent, postparent, xdata); + glupy_leave(gstate); + + return ret; + +unwind: + frame->local = NULL; + STACK_UNWIND_STRICT (create, frame, op_ret, op_errno, fd, inode, buf, + preparent, postparent, xdata); + return 0; +} + +int32_t +glupy_create (call_frame_t *frame, xlator_t *this, loc_t *loc, int32_t flags, + mode_t mode, mode_t umask, fd_t *fd, dict_t *xdata) +{ + glupy_private_t *priv = this->private; + PyGILState_STATE gstate; + int32_t ret; + static long next_id = 0; + + if (!priv->fops[GLUPY_CREATE]) { + goto wind; + } + + gstate = glupy_enter(); + frame->local = (void *)++next_id; + ret = ((fop_create_t)(priv->fops[GLUPY_CREATE]))( + frame, this, loc, flags, mode, umask, fd, xdata); + glupy_leave(gstate); + + return ret; + +wind: + STACK_WIND (frame, glupy_create_cbk, FIRST_CHILD(this), + FIRST_CHILD(this)->fops->create, loc, flags, mode, umask, + fd, xdata); + return 0; +} + +void +wind_create (call_frame_t *frame, xlator_t *xl, loc_t *loc, int32_t flags, + mode_t mode, mode_t umask, fd_t *fd, dict_t *xdata) +{ + + xlator_t *this = THIS; + + if (!xl || (xl == this)) { + xl = FIRST_CHILD(this); + } + + STACK_WIND (frame, glupy_create_cbk,xl, xl->fops->create, + loc, flags, mode, umask, fd, xdata); +} + +void +unwind_create (call_frame_t *frame, long cookie, xlator_t *this, + int32_t op_ret, int32_t op_errno, fd_t *fd, inode_t *inode, + struct iatt *buf, struct iatt *preparent, + struct iatt *postparent, dict_t *xdata) +{ + frame->local = NULL; + STACK_UNWIND_STRICT (create, frame, op_ret, op_errno, fd, inode, buf, + preparent, postparent, xdata); +} + +void +set_create_fop (long py_this, fop_create_t fop) +{ + glupy_private_t *priv = ((xlator_t *)py_this)->private; + + priv->fops[GLUPY_CREATE] = (long)fop; +} + +void +set_create_cbk (long py_this, fop_create_cbk_t cbk) +{ + glupy_private_t *priv = ((xlator_t *)py_this)->private; + + priv->cbks[GLUPY_CREATE] = (long)cbk; +} + +/* NON-FOP-SPECIFIC CODE */ + +long +get_id (call_frame_t *frame) +{ + return (long)(frame->local); +} + +int32_t +init (xlator_t *this) +{ + glupy_private_t *priv = NULL; + char *module_name = NULL; + PyObject *py_mod_name = NULL; + PyObject *py_init_func = NULL; + PyObject *py_args = NULL; + PyObject *syspath = NULL; + PyObject *path = NULL; + static gf_boolean_t py_inited = _gf_false; + void * err_cleanup = &&err_return; + + if (dict_get_str(this->options,"module-name",&module_name) != 0) { + gf_log (this->name, GF_LOG_ERROR, "missing module-name"); + return -1; + } + + priv = GF_CALLOC (1, sizeof (glupy_private_t), gf_glupy_mt_priv); + if (!priv) { + goto *err_cleanup; + } + this->private = priv; + err_cleanup = &&err_free_priv; + + if (!py_inited) { + Py_Initialize(); + PyEval_InitThreads(); +#if 0 + (void)pthread_key_create(&gil_init_key,NULL); + (void)pthread_setspecific(gil_init_key,(void *)1); +#endif + /* PyEval_InitThreads takes this "for" us. No thanks. */ + PyEval_ReleaseLock(); + py_inited = _gf_true; + } + + /* Adjust python's path */ + syspath = PySys_GetObject("path"); + path = PyString_FromString(GLUSTER_PYTHON_PATH); + PyList_Append(syspath, path); + Py_DECREF(path); + + py_mod_name = PyString_FromString(module_name); + if (!py_mod_name) { + gf_log (this->name, GF_LOG_ERROR, "could not create name"); + if (PyErr_Occurred()) { + PyErr_Print(); + } + goto *err_cleanup; + } + + priv->py_module = PyImport_Import(py_mod_name); + Py_DECREF(py_mod_name); + if (!priv->py_module) { + gf_log (this->name, GF_LOG_ERROR, "Python import failed"); + if (PyErr_Occurred()) { + PyErr_Print(); + } + goto *err_cleanup; + } + err_cleanup = &&err_deref_module; + + py_init_func = PyObject_GetAttrString(priv->py_module, "xlator"); + if (!py_init_func || !PyCallable_Check(py_init_func)) { + gf_log (this->name, GF_LOG_ERROR, "missing init func"); + if (PyErr_Occurred()) { + PyErr_Print(); + } + goto *err_cleanup; + } + err_cleanup = &&err_deref_init; + + py_args = PyTuple_New(1); + if (!py_args) { + gf_log (this->name, GF_LOG_ERROR, "could not create args"); + if (PyErr_Occurred()) { + PyErr_Print(); + } + goto *err_cleanup; + } + PyTuple_SetItem(py_args,0,PyLong_FromLong((long)this)); + + /* TBD: pass in list of children */ + priv->py_xlator = PyObject_CallObject(py_init_func, py_args); + Py_DECREF(py_args); + if (!priv->py_xlator) { + gf_log (this->name, GF_LOG_ERROR, "Python init failed"); + if (PyErr_Occurred()) { + PyErr_Print(); + } + goto *err_cleanup; + } + gf_log (this->name, GF_LOG_INFO, "init returned %p", priv->py_xlator); + + return 0; + +err_deref_init: + Py_DECREF(py_init_func); +err_deref_module: + Py_DECREF(priv->py_module); +err_free_priv: + GF_FREE(priv); +err_return: + return -1; +} + +void +fini (xlator_t *this) +{ + int i = 0; + glupy_private_t *priv = this->private; + + if (!priv) + return; + for (i = 0; i < GLUPY_N_FUNCS; ++i) { + if (priv->fops[i]) { + Py_DECREF(priv->fops[i]); + } + if (priv->cbks[i]) { + Py_DECREF(priv->fops[i]); + } + } + Py_DECREF(priv->py_xlator); + Py_DECREF(priv->py_module); + this->private = NULL; + GF_FREE (priv); + + return; +} + +struct xlator_fops fops = { + .lookup = glupy_lookup, + .create = glupy_create, +}; + +struct xlator_cbks cbks = { +}; + +struct volume_options options[] = { + { .key = {NULL} }, +}; diff --git a/xlators/features/glupy/src/glupy.h b/xlators/features/glupy/src/glupy.h new file mode 100644 index 00000000000..e6d2ff4f32c --- /dev/null +++ b/xlators/features/glupy/src/glupy.h @@ -0,0 +1,47 @@ +/* + Copyright (c) 2006-2011 Gluster, Inc. <http://www.gluster.com> + This file is part of GlusterFS. + + GlusterFS 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. + + GlusterFS 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/>. +*/ + +#ifndef __GLUPY_H__ +#define __GLUPY_H__ + +#ifndef _CONFIG_H +#define _CONFIG_H +#include "config.h" +#endif +#include "mem-types.h" + +enum { + GLUPY_LOOKUP = 0, + GLUPY_CREATE, + GLUPY_N_FUNCS +}; + +typedef struct { + PyObject *py_module; + PyObject *py_xlator; + long fops[GLUPY_N_FUNCS]; + long cbks[GLUPY_N_FUNCS]; +} glupy_private_t; + +enum gf_glupy_mem_types_ { + gf_glupy_mt_priv = gf_common_mt_end + 1, + gf_glupy_mt_end +}; + +#endif /* __GLUPY_H__ */ diff --git a/xlators/features/glupy/src/gluster.py b/xlators/features/glupy/src/gluster.py new file mode 100644 index 00000000000..ac732fb1733 --- /dev/null +++ b/xlators/features/glupy/src/gluster.py @@ -0,0 +1,118 @@ +import sys +from ctypes import * + +dl = CDLL("",RTLD_GLOBAL) + +class call_frame_t (Structure): + pass + +class dict_t (Structure): + pass + +class fd_t (Structure): + pass + +class iatt_t (Structure): + pass + +class inode_t (Structure): + pass + +class loc_t (Structure): + _fields_ = [ + ( "path", c_char_p ), + ( "name", c_char_p ), + ( "inode", c_void_p ), + ( "parent", c_void_p ), + # Not quite correct, but easier to manipulate. + ( "gfid", c_uint * 4 ), + ( "pargfid", c_uint * 4 ), + ] + +class xlator_t (Structure): + pass + +def _init_op (a_class, fop, cbk, wind, unwind): + # Decorators, used by translators. We could pass the signatures as + # parameters, but it's actually kind of nice to keep them around for + # inspection. + a_class.fop_type = apply(CFUNCTYPE,a_class.fop_sig) + a_class.cbk_type = apply(CFUNCTYPE,a_class.cbk_sig) + # Dispatch-function registration. + fop.restype = None + fop.argtypes = [ c_long, a_class.fop_type ] + # Callback-function registration. + cbk.restype = None + cbk.argtypes = [ c_long, a_class.cbk_type ] + # STACK_WIND function. + wind.restype = None + wind.argtypes = list(a_class.fop_sig[1:]) + # STACK_UNWIND function. + unwind.restype = None + unwind.argtypes = list(a_class.cbk_sig[1:]) + +class OpLookup: + fop_sig = (c_int, POINTER(call_frame_t), POINTER(xlator_t), + POINTER(loc_t), POINTER(dict_t)) + cbk_sig = (c_int, POINTER(call_frame_t), c_long, POINTER(xlator_t), + c_int, c_int, POINTER(inode_t), POINTER(iatt_t), + POINTER(dict_t), POINTER(iatt_t)) +_init_op (OpLookup, dl.set_lookup_fop, dl.set_lookup_cbk, + dl.wind_lookup, dl.unwind_lookup) + +class OpCreate: + fop_sig = (c_int, POINTER(call_frame_t), POINTER(xlator_t), + POINTER(loc_t), c_int, c_uint, c_uint, POINTER(fd_t), + POINTER(dict_t)) + cbk_sig = (c_int, POINTER(call_frame_t), c_long, POINTER(xlator_t), + c_int, c_int, POINTER(fd_t), POINTER(inode_t), + POINTER(iatt_t), POINTER(iatt_t), POINTER(iatt_t), + POINTER(dict_t)) +_init_op (OpCreate, dl.set_create_fop, dl.set_create_cbk, + dl.wind_create, dl.unwind_create) + +class Translator: + def __init__ (self, c_this): + # This is only here to keep references to the stubs we create, + # because ctypes doesn't and glupy.so can't because it doesn't + # get a pointer to the actual Python object. It's a dictionary + # instead of a list in case we ever allow changing fops/cbks + # after initialization and need to look them up. + self.stub_refs = {} + funcs = dir(self.__class__) + if "lookup_fop" in funcs: + @OpLookup.fop_type + def stub (frame, this, loc, xdata, s=self): + return s.lookup_fop (frame, this, loc, xdata) + self.stub_refs["lookup_fop"] = stub + dl.set_lookup_fop(c_this,stub) + if "lookup_cbk" in funcs: + @OpLookup.cbk_type + def stub (frame, cookie, this, op_ret, op_errno, inode, + buf, xdata, postparent, s=self): + return s.lookup_cbk(frame, cookie, this, op_ret, + op_errno, inode, buf, xdata, + postparent) + self.stub_refs["lookup_cbk"] = stub + dl.set_lookup_cbk(c_this,stub) + if "create_fop" in funcs: + @OpCreate.fop_type + def stub (frame, this, loc, flags, mode, umask, fd, + xdata, s=self): + return s.create_fop (frame, this, loc, flags, + mode, umask, fd, xdata) + self.stub_refs["create_fop"] = stub + dl.set_create_fop(c_this,stub) + if "create_cbk" in funcs: + @OpCreate.cbk_type + def stub (frame, cookie, this, op_ret, op_errno, fd, + inode, buf, preparent, postparent, xdata, + s=self): + return s.create_cbk (frame, cookie, this, + op_ret, op_errno, fd, + inode, buf, preparent, + postparent, xdata) + return 0 + self.stub_refs["create_cbk"] = stub + dl.set_create_cbk(c_this,stub) + diff --git a/xlators/features/glupy/src/helloworld.py b/xlators/features/glupy/src/helloworld.py new file mode 100644 index 00000000000..8fe4037118e --- /dev/null +++ b/xlators/features/glupy/src/helloworld.py @@ -0,0 +1,19 @@ +import sys +from gluster import * + +class xlator (Translator): + + def __init__(self, c_this): + Translator.__init__(self, c_this) + + def lookup_fop(self, frame, this, loc, xdata): + print "Python xlator: Hello!" + dl.wind_lookup(frame, POINTER(xlator_t)(), loc, xdata) + return 0 + + def lookup_cbk(self, frame, cookie, this, op_ret, op_errno, inode, buf, + xdata, postparent): + print "Python xlator: Hello again!" + dl.unwind_lookup(frame, cookie, this, op_ret, op_errno, inode, buf, + xdata, postparent) + return 0 diff --git a/xlators/features/glupy/src/negative.py b/xlators/features/glupy/src/negative.py new file mode 100644 index 00000000000..6ca855f72f0 --- /dev/null +++ b/xlators/features/glupy/src/negative.py @@ -0,0 +1,93 @@ +import sys +from gluster import * + +# Negative-lookup-caching example. If a file wasn't there the last time we +# looked, it's probably still not there. This translator keeps track of +# those failed lookups for us, and returns ENOENT without needing to pass the +# call any further for repeated requests. + +# If we were doing this for real, we'd need separate caches for each xlator +# instance. The easiest way to do this would be to have xlator.__init__ +# "register" each instance in a module-global dict, with the key as the C +# translator address and the value as the xlator object itself. For testing +# and teaching, it's sufficient just to have one cache. The keys are parent +# GFIDs, and the entries are lists of names within that parent that we know +# don't exist. +cache = {} + +# TBD: we need a better way of handling per-request data (frame->local in C). +dl.get_id.restype = c_long +dl.get_id.argtypes = [ POINTER(call_frame_t) ] + +def uuid2str (orig): + return "%08x%08x%08x%08x" % (orig[0], orig[1], orig[2], orig[3]) + +class xlator (Translator): + + def __init__ (self, c_this): + self.requests = {} + Translator.__init__(self,c_this) + + def lookup_fop (self, frame, this, loc, xdata): + pargfid = uuid2str(loc.contents.pargfid) + print "lookup FOP: %s:%s" % (pargfid, loc.contents.name) + # Check the cache. + if cache.has_key(pargfid): + if loc.contents.name in cache[pargfid]: + print "short-circuiting for %s:%s" % ( + pargfid, loc.contents.name) + dl.unwind_lookup(frame,0,this,-1,2,None,None, + None,None) + return 0 + key = dl.get_id(frame) + self.requests[key] = (pargfid, loc.contents.name[:]) + # TBD: get real child xl from init, pass it here + dl.wind_lookup(frame,POINTER(xlator_t)(),loc,xdata) + return 0 + + def lookup_cbk (self, frame, cookie, this, op_ret, op_errno, inode, buf, + xdata, postparent): + print "lookup CBK: %d (%d)" % (op_ret, op_errno) + key = dl.get_id(frame) + pargfid, name = self.requests[key] + # Update the cache. + if op_ret == 0: + print "found %s, removing from cache" % name + if cache.has_key(pargfid): + cache[pargfid].discard(name) + elif op_errno == 2: # ENOENT + print "failed to find %s, adding to cache" % name + if cache.has_key(pargfid): + cache[pargfid].add(name) + else: + cache[pargfid] = set([name]) + del self.requests[key] + dl.unwind_lookup(frame,cookie,this,op_ret,op_errno, + inode,buf,xdata,postparent) + return 0 + + def create_fop (self, frame, this, loc, flags, mode, umask, fd, xdata): + pargfid = uuid2str(loc.contents.pargfid) + print "create FOP: %s:%s" % (pargfid, loc.contents.name) + key = dl.get_id(frame) + self.requests[key] = (pargfid, loc.contents.name[:]) + # TBD: get real child xl from init, pass it here + dl.wind_create(frame,POINTER(xlator_t)(),loc,flags,mode,umask, + fd,xdata) + return 0 + + def create_cbk (self, frame, cookie, this, op_ret, op_errno, fd, inode, + buf, preparent, postparent, xdata): + print "create CBK: %d (%d)" % (op_ret, op_errno) + key = dl.get_id(frame) + pargfid, name = self.requests[key] + # Update the cache. + if op_ret == 0: + print "created %s, removing from cache" % name + if cache.has_key(pargfid): + cache[pargfid].discard(name) + del self.requests[key] + dl.unwind_create(frame,cookie,this,op_ret,op_errno,fd,inode,buf, + preparent,postparent,xdata) + return 0 + |