similar to: [PATCH libnbd v2] python: Raise a custom exception containing error string and errno.

Following Eric's suggestions from v2, this adds .string, .errno and .__str__ properties. The .string property returns the error string. The .errno property returns the errno (from the errno module), or None. The __str__ property makes the exception nicely printable. Rich.

I spent a good few hours this morning trying to make this work and came up with the following patch. It's not quite right though. The exception I've created exists in the libnbdmod module (ie. the underlying C module that we use for the Python bindings). Ideally we'd define and throw an exception from the normal nbd module, but I couldn't work out how to do that. Probably

Previously errors caused a RuntimeException to be raised. This commit defines a custom exception (nbd.Error) which has two parameters, the required error string, and the optional errno (which may be 0 if unavailable). For example: $ ./run nbdsh -c 'h.pread(0, 0)' Traceback (most recent call last): File "/usr/lib64/python3.7/runpy.py", line 193, in _run_module_as_main

Previously errors caused a RuntimeException to be raised. This commit defines a custom exception (nbd.Error) which has two parameters, the required error string, and the optional errno (which may be 0 if unavailable). For example: $ ./run nbdsh -c 'h.pread(0, 0)' Traceback (most recent call last): File "/usr/lib64/python3.7/runpy.py", line 193, in _run_module_as_main

On 6/28/19 1:27 PM, Richard W.M. Jones wrote: > Previously errors caused a RuntimeException to be raised. This commit > defines a custom exception (nbd.Error) which has two parameters, the > required error string, and the optional errno (which may be 0 if > unavailable). > > For example: > > $ ./run nbdsh -c 'h.pread(0, 0)' > Traceback (most recent call last):

On 8/13/19 5:06 AM, Richard W.M. Jones wrote: > An optional Closure parameter, but otherwise works the same way as > Closure. > @@ -3778,6 +3777,7 @@ let generate_lib_api_c () = > ) args; > List.iter ( > function > + | OClosure { cbname } -> pr ", %s_callback ? \"<fun>\" : \"NULL\"" cbname Well, it also permits a

This doesn't yet work. However it does make me more convinced than ever that we really need to sort out persistent buffer lifetimes in the library (similar to what we did for closures). Rich.

I noticed these while working on adding fua support into python, these are independent enough to push now (and I'll have to rebase my 'optional may_trim' patch on top of this). Eric Blake (2): python: Use Py_XDEFREF() python: Simplify calling into plugin plugins/python/python.c | 106 ++++++++---------------------------------------- 1 file changed, 18 insertions(+), 88

The current need for #ifdef's based on the presence of PyString_FromString makes both the OCaml code of the generator, and the generated C code a mess to read. Hence, add three simple wrappers to make both the OCaml, and C code more readable, and easier to tweak in the future. --- generator/python.ml | 72 ++++++++++++----------------------------------------- python/handle.c | 65

v1: https://www.redhat.com/archives/libguestfs/2019-November/msg00153.html v2: - Fix implementation of can_cache. - Add implementation of can_fua. - Add a very thorough test suite which tests every command + flag combination.

v1 was here: https://www.redhat.com/archives/libguestfs/2019-August/msg00103.html In v2 I've made several changes: - Fix Python callbacks so if they don't return something which is int-like, we assume they mean to return 0. - Add nbd.Buffer free() method. Read commit message in patch 2 to see what this is about. - Fixed the asynch copy test to deal with the unbelievably

This series addresses the issue where non UTF8 file names in a guest image lead to libguestfs segfault with Python 3 APIs. The core issue is the APIs are not checking the return value when constructing a new PyObject. Therefore NULL pointers are added to Python collections (lists and dictionaries) crashing the application. Few notes regarding the comments on the previous patch. - Added a

Fix some things I noticed while reviewing v1, and follow Rich's idea to add a new nbdkit_set_error() utility function with a binding for Python users to request a particular error (rather than being forced to live with whatever stale value is in errno after all the intermediate binding glue code). I could not easily find out how to register a C function callable from perl bindings, and have

Verify the returned values of Python Object constructor functions are not NULL before adding them to a collection. This is particularly relevant when constructing Unicode strings in Python 3 as they will return NULL if non UTF-8 characters are present. Signed-off-by: Matteo Cafasso <noxdafox@gmail.com> --- generator/python.ml | 102 ++++++++++++++++++++++++++---------------

And fill out most of the missing bits of the API. Rich.

Begin the language binding followups to my new .zero callback, since Rich was indeed correct that we want them. I'm more familiar with python and perl (at least to the point that I was able to modify the appropriate example files and prove to myself that the bindings worked), so I've started with those. I'm less familiar with ruby and ocaml, so I've left those for tomorrow (it

On Mon, Mar 23, 2020 at 12:28:12PM +0000, Richard W.M. Jones wrote: > From: Yifan Gu <gyf304@gmail.com> > > The create_nbdkit_module function is intended to be exported, therefore > the static keyword is not needed and prevents building on MSYS2. > --- > plugins/python/python.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git

In preparation for adding other optional flag arguments to the python bindings, start by making the existing 'may_trim' flag to 'zero' be optional. That is, the plugin need not define the parameter if it does not make any semantic difference (ie. if the plugin ignores the hint and never trims); while if the parameter exists, we now pass it as a keyword argument rather than as a

This fixes Github issue #2 reported by "kupiakos". <https://github.com/libguestfs/hivex/issues/2> --- generator/generator.ml | 2 +- python/t/210-setvalue.py | 26 +++++++++++++++++--------- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/generator/generator.ml b/generator/generator.ml index 908c5f3..02aaf12 100755 --- a/generator/generator.ml +++

This patch proposes to drop support for Python 2 in nbdkit. Rather than abruptly drop it everywhere, my proposal is that we point people to nbdkit 1.14 (the current stable version) if they want to continue with Python 2 plugins, while gently reminding them of the upcoming Python 2.7 end of life announcement. Libnbd never supported Python 2. Libguestfs in theory supports Python 2 but I dropped