[Libguestfs] [libnbd PATCH 2/2] RFC: generator: Handle shared callbacks in Python
Eric Blake
eblake at redhat.com
Tue Jul 16 04:38:12 UTC 2019
[RFC because generated OCaml code needs the same treatment, but I ran
out of time to play with that. At least 'make -C python check' passes,
although coverage is not complete yet, as there is no
python/t/5XX-pread-structured-callback.py...]
[Also RFC because I'm not sure if the use of a record type for
'callback' is the best approach or most idiomatic OCaml - but hey, it
taught me a lot about OCaml. Writing a 'string * callback list' proved
to be a rather interesting exercise]
Our C code has a couple of functions that want to take multiple
callback functions that share a single opaque data
(nbd_aio_pread_structured_callback; nbd_aio_block_status_callback).
However, the mapping of this construct to Python passed only the
opaque handle of the first function to the second callback wrapper,
which means we would invoke the wrong Python Callable; better is
tracking a single malloc()d structure containing the Python opaque
object, and ALL of the Python Callables that reuse that same opaque
object.
We could either add lots of static checking that a
Callback/CallbackPersist cannot appear in the argument list until
after an earlier Opaque, and that the argument name for top-level
Opaque also appears as the first argument for the callback function.
Or, we could bundle the construct through a better constructor that
tracks that an opaque argument and one or more callback functions must
be handled as a unit, where the callback function automatically
outputs the opaque argument first. This patch attempts the latter.
It may also be worth comparing a diff of the generated
python/methods.c before and after this patch, to see what changes.
---
generator/generator | 542 ++++++++++++++++++++++----------------------
1 file changed, 272 insertions(+), 270 deletions(-)
diff --git a/generator/generator b/generator/generator
index ad12b36..e48b1ad 100755
--- a/generator/generator
+++ b/generator/generator
@@ -841,6 +841,13 @@ type call = {
*)
may_set_error : bool;
}
+and callback = {
+ name : string; (* callback name *)
+ cbargs : arg list; (* parameters (except opaque) *)
+ (* For now, all callbacks return int; we could list a return type here if
+ * more variety is needed.
+ *)
+}
and arg =
| ArrayAndLen of arg * string (* array + number of entries *)
| Bool of string (* bool *)
@@ -849,13 +856,14 @@ and arg =
written by the function *)
| BytesPersistIn of string * string (* same as above, but buffer persists *)
| BytesPersistOut of string * string
-| Callback of string * arg list (* callback function returning int *)
-| CallbackPersist of string * arg list (* as above, but callback persists *)
| Flags of string (* NBD_CMD_FLAG_* flags *)
| Int of string (* small int *)
| Int64 of string (* 64 bit signed int *)
| Mutable of arg (* mutable argument, eg. int* *)
-| Opaque of string (* opaque object, void* in C *)
+| OpaqueAndCallbacks of string * callback list (* one or more callbacks
+ * sharing same opaque *)
+| OpaqueAndCallbacksPersist of string * callback list (* as above, but opaque
+ * persists *)
| Path of string (* filename or path *)
| SockAddrAndLen of string * string (* struct sockaddr * + socklen_t *)
| String of string (* string *)
@@ -915,9 +923,10 @@ Return the state of the debug flag on this handle.";
"set_debug_callback", {
default_call with
- args = [ Opaque "data";
- CallbackPersist ("debug_fn", [Opaque "data";
- String "context"; String "msg"]) ];
+ args = [ OpaqueAndCallbacksPersist ("data",
+ [ {name="debug_fn";
+ cbargs=[ String "context";
+ String "msg" ]}]) ];
ret = RErr;
shortdesc = "set the debug callback";
longdesc = "\
@@ -1345,10 +1354,11 @@ protocol extensions).";
"pread_structured", {
default_call with
args = [ BytesOut ("buf", "count"); UInt64 "offset";
- Opaque "data";
- Callback ("chunk", [ Opaque "data"; BytesIn ("subbuf", "count");
- UInt64 "offset"; Int "status";
- Mutable (Int "error"); ]);
+ OpaqueAndCallbacks ("data",
+ [ {name="chunk";
+ cbargs=[ BytesIn ("subbuf", "count");
+ UInt64 "offset"; Int "status";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RErr;
permitted_states = [ Connected ];
@@ -1534,12 +1544,13 @@ punching a hole.";
"block_status", {
default_call with
args = [ UInt64 "count"; UInt64 "offset";
- Opaque "data";
- Callback ("extent", [Opaque "data"; String "metacontext";
- UInt64 "offset";
- ArrayAndLen (UInt32 "entries",
- "nr_entries");
- Mutable (Int "error")]);
+ OpaqueAndCallbacks ("data",
+ [ {name="extent";
+ cbargs=[String "metacontext";
+ UInt64 "offset";
+ ArrayAndLen (UInt32 "entries",
+ "nr_entries");
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RErr;
permitted_states = [ Connected ];
@@ -1717,9 +1728,10 @@ C<nbd_pread>.";
"aio_pread_callback", {
default_call with
args = [ BytesPersistOut ("buf", "count"); UInt64 "offset";
- Opaque "data";
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -1747,12 +1759,12 @@ cause a deadlock.";
"aio_pread_structured", {
default_call with
args = [ BytesPersistOut ("buf", "count"); UInt64 "offset";
- Opaque "data";
- CallbackPersist ("chunk", [ Opaque "data";
- BytesIn ("subbuf", "count");
- UInt64 "offset";
- Int "status";
- Mutable (Int "error"); ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="chunk";
+ cbargs=[ BytesIn ("subbuf", "count");
+ UInt64 "offset";
+ Int "status";
+ Mutable (Int "error"); ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -1769,14 +1781,15 @@ documented in C<nbd_pread_structured>.";
"aio_pread_structured_callback", {
default_call with
args = [ BytesPersistOut ("buf", "count"); UInt64 "offset";
- Opaque "data";
- CallbackPersist ("chunk", [ Opaque "data";
- BytesIn ("subbuf", "count");
- UInt64 "offset";
- Int "status";
- Mutable (Int "error"); ]);
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="chunk";
+ cbargs=[ BytesIn ("subbuf", "count");
+ UInt64 "offset";
+ Int "status";
+ Mutable (Int "error"); ]};
+ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -1819,9 +1832,10 @@ C<nbd_pwrite>.";
"aio_pwrite_callback", {
default_call with
args = [ BytesPersistIn ("buf", "count"); UInt64 "offset";
- Opaque "data";
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -1884,9 +1898,10 @@ Parameters behave as documented in C<nbd_flush>.";
"aio_flush_callback", {
default_call with
- args = [ Opaque "data";
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ args = [ OpaqueAndCallbacksPersist ("data",
+ [ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -1927,9 +1942,10 @@ Parameters behave as documented in C<nbd_trim>.";
"aio_trim_callback", {
default_call with
args = [ UInt64 "count"; UInt64 "offset";
- Opaque "data";
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -1970,9 +1986,10 @@ Parameters behave as documented in C<nbd_cache>.";
"aio_cache_callback", {
default_call with
args = [ UInt64 "count"; UInt64 "offset";
- Opaque "data";
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -2013,9 +2030,10 @@ Parameters behave as documented in C<nbd_zero>.";
"aio_zero_callback", {
default_call with
args = [ UInt64 "count"; UInt64 "offset";
- Opaque "data";
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -2042,12 +2060,13 @@ cause a deadlock.";
"aio_block_status", {
default_call with
args = [ UInt64 "count"; UInt64 "offset";
- Opaque "data";
- CallbackPersist ("extent", [Opaque "data"; String "metacontext";
- UInt64 "offset";
- ArrayAndLen (UInt32 "entries",
- "nr_entries");
- Mutable (Int "error")]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="extent";
+ cbargs=[ String "metacontext";
+ UInt64 "offset";
+ ArrayAndLen (UInt32 "entries",
+ "nr_entries");
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -2063,14 +2082,16 @@ Parameters behave as documented in C<nbd_block_status>.";
"aio_block_status_callback", {
default_call with
args = [ UInt64 "count"; UInt64 "offset";
- Opaque "data";
- CallbackPersist ("extent", [Opaque "data"; String "metacontext";
- UInt64 "offset";
- ArrayAndLen (UInt32 "entries",
- "nr_entries");
- Mutable (Int "error") ]);
- CallbackPersist ("callback", [ Opaque "data"; Int64 "cookie";
- Mutable (Int "error") ]);
+ OpaqueAndCallbacksPersist ("data",
+ [ {name="extent";
+ cbargs=[ String "metacontext";
+ UInt64 "offset";
+ ArrayAndLen (UInt32 "entries",
+ "nr_entries");
+ Mutable (Int "error") ]};
+ {name="callback";
+ cbargs=[ Int64 "cookie";
+ Mutable (Int "error") ]}]);
Flags "flags" ];
ret = RInt64;
permitted_states = [ Connected ];
@@ -3150,11 +3171,11 @@ let rec name_of_arg = function
| BytesOut (n, len) -> [n; len]
| BytesPersistIn (n, len) -> [n; len]
| BytesPersistOut (n, len) -> [n; len]
-| Callback (n, _) | CallbackPersist (n, _) -> [n]
| Flags n -> [n]
| Int n -> [n]
| Int64 n -> [n]
-| Opaque n -> [n]
+| OpaqueAndCallbacks (n, cbs) | OpaqueAndCallbacksPersist (n, cbs) ->
+ [n] @ List.map (fun cb -> cb.name) cbs
| Mutable arg -> name_of_arg arg
| Path n -> [n]
| SockAddrAndLen (n, len) -> [n; len]
@@ -3185,15 +3206,17 @@ let rec print_c_arg_list ?(handle = None) args =
| BytesPersistIn (n, len) -> pr "const void *%s, size_t %s" n len
| BytesOut (n, len)
| BytesPersistOut (n, len) -> pr "void *%s, size_t %s" n len
- | Callback (n, args)
- | CallbackPersist (n, args) ->
- pr "int (*%s) " n; print_c_arg_list args
| Flags n -> pr "uint32_t %s" n
| Int n -> pr "int %s" n
| Int64 n -> pr "int64_t %s" n
| Mutable (Int n) -> pr "int *%s" n
| Mutable arg -> assert false
- | Opaque n -> pr "void *%s" n
+ | OpaqueAndCallbacks (n, cbs) | OpaqueAndCallbacksPersist (n, cbs) ->
+ pr "void *%s" n;
+ List.iter (fun cb ->
+ let first = "void *" ^ n in
+ pr ", int (*%s)" cb.name;
+ print_c_arg_list ~handle:(Some first) cb.cbargs) cbs
| Path n
| String n -> pr "const char *%s" n
| StringList n -> pr "char **%s" n
@@ -3715,155 +3738,138 @@ let print_python_binding name { args; ret } =
* have to generate a wrapper function which translates the
* callback parameters back to Python.
*)
- let find_callback opaque_id =
- let cb =
- try
- List.find (
- function
- | Callback (_, args) | CallbackPersist (_, args) ->
- List.mem (Opaque opaque_id) args
- | _ -> false
- ) args
- with
- Not_found ->
- failwithf "%s: couldn't find callback associated with Opaque %s"
- name opaque_id in
- match cb with
- | Callback (name, _) | CallbackPersist (name, _) -> name
- | _ -> assert false
+ let print_callback cb =
+ pr "static int\n";
+ pr "%s_%s_wrapper " name cb.name;
+ print_c_arg_list ~handle:(Some "void *_data") cb.cbargs;
+ pr "\n";
+ pr "{\n";
+ pr " int ret;\n";
+ pr " PyGILState_STATE py_save = PyGILState_UNLOCKED;\n";
+ pr " PyObject *py_args, *py_ret;\n";
+ pr " struct %s_data *data = _data;\n" name;
+ List.iter (
+ function
+ | ArrayAndLen (UInt32 n, len) ->
+ pr " PyObject *py_%s = PyList_New (%s);\n" n len;
+ pr " for (size_t i = 0; i < %s; ++i)\n" len;
+ pr " PyList_SET_ITEM (py_%s, i, PyLong_FromUnsignedLong (%s[i]));\n" n n
+ | BytesIn _
+ | Int _
+ | Int64 _ -> ()
+ | Mutable (Int n) ->
+ pr " PyObject *py_%s_modname = PyUnicode_FromString (\"ctypes\");\n" n;
+ pr " if (!py_%s_modname) { PyErr_PrintEx (0); return -1; }\n" n;
+ pr " PyObject *py_%s_mod = PyImport_Import (py_%s_modname);\n" n n;
+ pr " Py_DECREF (py_%s_modname);\n" n;
+ pr " if (!py_%s_mod) { PyErr_PrintEx (0); return -1; }\n" n;
+ pr " PyObject *py_%s = PyObject_CallMethod (py_%s_mod, \"c_int\", \"i\", *%s);\n" n n n;
+ pr " if (!py_%s) { PyErr_PrintEx (0); return -1; }\n" n;
+ | String n
+ | UInt64 n -> ()
+ (* The following not yet implemented for callbacks XXX *)
+ | ArrayAndLen _ | Bool _ | BytesOut _
+ | BytesPersistIn _ | BytesPersistOut _
+ | Flags _ | Mutable _
+ | OpaqueAndCallbacks _ | OpaqueAndCallbacksPersist _
+ | Path _ | SockAddrAndLen _ | StringList _
+ | UInt _ | UInt32 _ -> assert false
+ ) cb.cbargs;
+ pr "\n";
+
+ pr " py_args = Py_BuildValue (\"(O\"";
+ List.iter (
+ function
+ | ArrayAndLen (UInt32 n, len) -> pr " \"O\""
+ | BytesIn (n, len) -> pr " \"y#\""
+ | Int n -> pr " \"i\""
+ | Int64 n -> pr " \"L\""
+ | Mutable (Int n) -> pr " \"O\""
+ | String n -> pr " \"s\""
+ | UInt64 n -> pr " \"K\""
+ (* The following not yet implemented for callbacks XXX *)
+ | ArrayAndLen _ | Bool _ | BytesOut _
+ | BytesPersistIn _ | BytesPersistOut _
+ | Flags _ | Mutable _
+ | OpaqueAndCallbacks _ | OpaqueAndCallbacksPersist _
+ | Path _ | SockAddrAndLen _ | StringList _
+ | UInt _ | UInt32 _ -> assert false
+ ) cb.cbargs;
+ pr " \")\", data->data";
+ List.iter (
+ function
+ | ArrayAndLen (UInt32 n, _) -> pr ", py_%s" n
+ | BytesIn (n, len) -> pr ", %s, (int) %s" n len
+ | Mutable (Int n) -> pr ", py_%s" n
+ | Int n | Int64 n
+ | String n
+ | UInt64 n -> pr ", %s" n
+ (* The following not yet implemented for callbacks XXX *)
+ | ArrayAndLen _ | Bool _ | BytesOut _
+ | BytesPersistIn _ | BytesPersistOut _
+ | Flags _ | Mutable _
+ | OpaqueAndCallbacks _ | OpaqueAndCallbacksPersist _
+ | Path _ | SockAddrAndLen _ | StringList _
+ | UInt _ | UInt32 _ -> assert false
+ ) cb.cbargs;
+ pr ");\n";
+ pr " Py_INCREF (py_args);\n";
+ pr "\n";
+ pr " if (PyEval_ThreadsInitialized ())\n";
+ pr " py_save = PyGILState_Ensure ();\n";
+ pr "\n";
+ pr " py_ret = PyObject_CallObject (data->%s, py_args);\n" cb.name;
+ pr "\n";
+ pr " if (PyEval_ThreadsInitialized ())\n";
+ pr " PyGILState_Release (py_save);\n";
+ pr "\n";
+ pr " Py_DECREF (py_args);\n";
+ pr "\n";
+ pr " if (py_ret != NULL) {\n";
+ pr " ret = 0;\n";
+ pr " Py_DECREF (py_ret); /* return value is discarded */\n";
+ pr " }\n";
+ pr " else {\n";
+ pr " ret = -1;\n";
+ pr " PyErr_PrintEx (0); /* print exception */\n";
+ pr " };\n";
+ pr "\n";
+ List.iter (
+ function
+ | ArrayAndLen (UInt32 n, _) ->
+ pr " Py_DECREF (py_%s);\n" n
+ | Mutable (Int n) ->
+ pr " PyObject *py_%s_ret = PyObject_GetAttrString (py_%s, \"value\");\n" n n;
+ pr " *%s = PyLong_AsLong (py_%s_ret);\n" n n;
+ pr " Py_DECREF (py_%s_ret);\n" n;
+ pr " Py_DECREF (py_%s);\n" n
+ | BytesIn _
+ | Int _ | Int64 _
+ | String _
+ | UInt64 _ -> ()
+ (* The following not yet implemented for callbacks XXX *)
+ | ArrayAndLen _ | Bool _ | BytesOut _
+ | BytesPersistIn _ | BytesPersistOut _
+ | Flags _ | Mutable _
+ | OpaqueAndCallbacks _ | OpaqueAndCallbacksPersist _
+ | Path _ | SockAddrAndLen _ | StringList _
+ | UInt _ | UInt32 _ -> assert false
+ ) cb.cbargs;
+ pr " return ret;\n";
+ pr "}\n";
+ pr "\n"
in
List.iter (
function
- | Callback (cb_name, args) | CallbackPersist (cb_name, args) ->
- pr "struct %s_%s_data {\n" name cb_name;
- pr " PyObject *fn;\n";
+ | OpaqueAndCallbacks (data, cbs) | OpaqueAndCallbacksPersist (data, cbs) ->
+ pr "struct %s_data {\n" name;
pr " PyObject *data;\n";
+ List.iter (fun cb ->
+ pr " PyObject *%s;\n" cb.name) cbs;
pr "};\n";
pr "\n";
- pr "static int\n";
- pr "%s_%s_wrapper " name cb_name;
- print_c_arg_list args;
- pr "\n";
- pr "{\n";
- pr " int ret;\n";
- pr " PyGILState_STATE py_save = PyGILState_UNLOCKED;\n";
- pr " PyObject *py_args, *py_ret;\n";
- List.iter (
- function
- | ArrayAndLen (UInt32 n, len) ->
- pr " PyObject *py_%s = PyList_New (%s);\n" n len;
- pr " for (size_t i = 0; i < %s; ++i)\n" len;
- pr " PyList_SET_ITEM (py_%s, i, PyLong_FromUnsignedLong (%s[i]));\n" n n
- | BytesIn _
- | Int _
- | Int64 _ -> ()
- | Mutable (Int n) ->
- pr " PyObject *py_%s_modname = PyUnicode_FromString (\"ctypes\");\n" n;
- pr " if (!py_%s_modname) { PyErr_PrintEx (0); return -1; }\n" n;
- pr " PyObject *py_%s_mod = PyImport_Import (py_%s_modname);\n" n n;
- pr " Py_DECREF (py_%s_modname);\n" n;
- pr " if (!py_%s_mod) { PyErr_PrintEx (0); return -1; }\n" n;
- pr " PyObject *py_%s = PyObject_CallMethod (py_%s_mod, \"c_int\", \"i\", *%s);\n" n n n;
- pr " if (!py_%s) { PyErr_PrintEx (0); return -1; }\n" n;
- | Opaque n ->
- pr " struct %s_%s_data *_data = %s;\n" name cb_name n
- | String n
- | UInt64 n -> ()
- (* The following not yet implemented for callbacks XXX *)
- | ArrayAndLen _ | Bool _ | BytesOut _
- | BytesPersistIn _ | BytesPersistOut _
- | Callback _ | CallbackPersist _
- | Flags _ | Mutable _
- | Path _ | SockAddrAndLen _ | StringList _
- | UInt _ | UInt32 _ -> assert false
- ) args;
- pr "\n";
-
- pr " py_args = Py_BuildValue (\"(\"";
- List.iter (
- function
- | ArrayAndLen (UInt32 n, len) -> pr " \"O\""
- | BytesIn (n, len) -> pr " \"y#\""
- | Int n -> pr " \"i\""
- | Int64 n -> pr " \"L\""
- | Mutable (Int n) -> pr " \"O\""
- | Opaque n -> pr " \"O\""
- | String n -> pr " \"s\""
- | UInt64 n -> pr " \"K\""
- (* The following not yet implemented for callbacks XXX *)
- | ArrayAndLen _ | Bool _ | BytesOut _
- | BytesPersistIn _ | BytesPersistOut _
- | Callback _ | CallbackPersist _
- | Flags _ | Mutable _
- | Path _ | SockAddrAndLen _ | StringList _
- | UInt _ | UInt32 _ -> assert false
- ) args;
- pr " \")\"";
- List.iter (
- function
- | ArrayAndLen (UInt32 n, _) -> pr ", py_%s" n
- | BytesIn (n, len) -> pr ", %s, (int) %s" n len
- | Mutable (Int n) -> pr ", py_%s" n
- | Opaque _ -> pr ", _data->data"
- | Int n | Int64 n
- | String n
- | UInt64 n -> pr ", %s" n
- (* The following not yet implemented for callbacks XXX *)
- | ArrayAndLen _ | Bool _ | BytesOut _
- | BytesPersistIn _ | BytesPersistOut _
- | Callback _ | CallbackPersist _
- | Flags _ | Mutable _
- | Path _ | SockAddrAndLen _ | StringList _
- | UInt _ | UInt32 _ -> assert false
- ) args;
- pr ");\n";
- pr " Py_INCREF (py_args);\n";
- pr "\n";
- pr " if (PyEval_ThreadsInitialized ())\n";
- pr " py_save = PyGILState_Ensure ();\n";
- pr "\n";
- pr " py_ret = PyObject_CallObject (_data->fn, py_args);\n";
- pr "\n";
- pr " if (PyEval_ThreadsInitialized ())\n";
- pr " PyGILState_Release (py_save);\n";
- pr "\n";
- pr " Py_DECREF (py_args);\n";
- pr "\n";
- pr " if (py_ret != NULL) {\n";
- pr " ret = 0;\n";
- pr " Py_DECREF (py_ret); /* return value is discarded */\n";
- pr " }\n";
- pr " else {\n";
- pr " ret = -1;\n";
- pr " PyErr_PrintEx (0); /* print exception */\n";
- pr " };\n";
- pr "\n";
- List.iter (
- function
- | ArrayAndLen (UInt32 n, _) ->
- pr " Py_DECREF (py_%s);\n" n
- | Mutable (Int n) ->
- pr " PyObject *py_%s_ret = PyObject_GetAttrString (py_%s, \"value\");\n" n n;
- pr " *%s = PyLong_AsLong (py_%s_ret);\n" n n;
- pr " Py_DECREF (py_%s_ret);\n" n;
- pr " Py_DECREF (py_%s);\n" n
- | BytesIn _
- | Int _ | Int64 _
- | Opaque _
- | String _
- | UInt64 _ -> ()
- (* The following not yet implemented for callbacks XXX *)
- | ArrayAndLen _ | Bool _ | BytesOut _
- | BytesPersistIn _ | BytesPersistOut _
- | Callback _ | CallbackPersist _
- | Flags _ | Mutable _
- | Path _ | SockAddrAndLen _ | StringList _
- | UInt _ | UInt32 _ -> assert false
- ) args;
- pr " return ret;\n";
- pr "}\n";
- pr "\n"
+ List.iter (fun cb -> print_callback cb) cbs
| _ -> ()
) args;
@@ -3901,10 +3907,6 @@ let print_python_binding name { args; ret } =
pr " PyObject *%s; /* PyCapsule pointing to struct py_aio_buffer */\n"
n;
pr " struct py_aio_buffer *%s_buf;\n" n
- | Callback (n, _) ->
- pr " struct %s_%s_data _%s_data, *%s_data = &_%s_data;\n" name n n n n
- | CallbackPersist (n, _) ->
- pr " struct %s_%s_data *%s_data;\n" name n n
| Flags n ->
pr " uint32_t %s_u32;\n" n;
pr " unsigned int %s; /* really uint32_t */\n" n
@@ -3914,7 +3916,10 @@ let print_python_binding name { args; ret } =
pr " long long %s; /* really int64_t */\n" n
| Mutable arg ->
pr " PyObject *%s;\n" (List.hd (name_of_arg arg))
- | Opaque _ -> ()
+ | OpaqueAndCallbacks (n, _) ->
+ pr " struct %s_data _%s, *%s = &_%s;\n" name n n n
+ | OpaqueAndCallbacksPersist (n, _) ->
+ pr " struct %s_data *%s;\n" name n
| Path n ->
pr " PyObject *py_%s = NULL;\n" n;
pr " char *%s = NULL;\n" n
@@ -3946,17 +3951,16 @@ let print_python_binding name { args; ret } =
| BytesPersistIn _
| BytesOut _
| BytesPersistOut _
- | Callback _ -> ()
- | CallbackPersist (n, _) ->
- pr " %s_data = malloc (sizeof *%s_data);\n" n n;
- pr " if (%s_data == NULL) {\n" n;
- pr " PyErr_NoMemory ();\n";
- pr " return NULL;\n";
- pr " }\n"
| Flags _
| Int _
| Int64 _
- | Opaque _
+ | OpaqueAndCallbacks _ -> ()
+ | OpaqueAndCallbacksPersist (n, _) ->
+ pr " %s = malloc (sizeof *%s);\n" n n;
+ pr " if (%s == NULL) {\n" n;
+ pr " PyErr_NoMemory ();\n";
+ pr " return NULL;\n";
+ pr " }\n"
| Mutable _
| Path _
| SockAddrAndLen _
@@ -3977,12 +3981,13 @@ let print_python_binding name { args; ret } =
| BytesPersistIn (n, _) -> pr " \"O\""
| BytesOut (_, count) -> pr " \"n\""
| BytesPersistOut (_, count) -> pr " \"O\""
- | Callback (n, _) | CallbackPersist (n, _) -> pr " \"O\""
| Flags n -> pr " \"I\""
| Int n -> pr " \"i\""
| Int64 n -> pr " \"L\""
| Mutable _ -> pr " \"O\""
- | Opaque _ -> pr " \"O\""
+ | OpaqueAndCallbacks (n, cbs) | OpaqueAndCallbacksPersist (n, cbs) ->
+ pr " \"O\"";
+ List.iter (fun _ -> pr " \"O\"") cbs
| Path n -> pr " \"O&\""
| SockAddrAndLen (n, _) -> pr " \"O\""
| String n -> pr " \"s\""
@@ -4002,12 +4007,13 @@ let print_python_binding name { args; ret } =
| BytesIn (n, _) | BytesPersistIn (n, _)
| BytesPersistOut (n, _) -> pr ", &%s" n
| BytesOut (_, count) -> pr ", &%s" count
- | Callback (n, _) | CallbackPersist (n, _) -> pr ", &%s_data->fn" n
| Flags n -> pr ", &%s" n
| Int n -> pr ", &%s" n
| Int64 n -> pr ", &%s" n
| Mutable arg -> pr ", &%s" (List.hd (name_of_arg arg))
- | Opaque n -> pr ", &%s_data->data" (find_callback n)
+ | OpaqueAndCallbacks (n, cbs) | OpaqueAndCallbacksPersist (n, cbs) ->
+ pr ", &%s->data" n;
+ List.iter (fun cb -> pr ", &%s->%s" n cb.name) cbs
| Path n -> pr ", PyUnicode_FSConverter, &py_%s" n
| SockAddrAndLen (n, _) -> pr ", &%s" n
| String n -> pr ", &%s" n
@@ -4046,19 +4052,20 @@ let print_python_binding name { args; ret } =
pr " %s = malloc (%s);\n" n count
| BytesPersistIn (n, _) | BytesPersistOut (n, _) ->
pr " %s_buf = nbd_internal_py_get_aio_buffer (%s);\n" n n
- | Callback (n, _) | CallbackPersist (n, _) ->
- pr " if (!PyCallable_Check (%s_data->fn)) {\n" n;
- pr " PyErr_SetString (PyExc_TypeError,\n";
- pr " \"callback parameter %s is not callable\");\n"
- n;
- pr " return NULL;\n";
- pr " }\n"
| Flags n -> pr " %s_u32 = %s;\n" n n
| Int _ -> ()
| Int64 n -> pr " %s_i64 = %s;\n" n n
| Mutable _ ->
pr " abort (); /* Mutable for normal Python parameters not impl */\n"
- | Opaque n -> ()
+ | OpaqueAndCallbacks (n, cbs) | OpaqueAndCallbacksPersist (n, cbs) ->
+ List.iter (fun cb ->
+ pr " if (!PyCallable_Check (%s->%s)) {\n" n cb.name;
+ pr " PyErr_SetString (PyExc_TypeError,\n";
+ pr " \"callback parameter %s is not callable\");\n"
+ cb.name;
+ pr " return NULL;\n";
+ pr " }\n"
+ ) cbs
| Path n ->
pr " %s = PyBytes_AS_STRING (py_%s);\n" n n;
pr " assert (%s != NULL);\n" n
@@ -4084,12 +4091,13 @@ let print_python_binding name { args; ret } =
| BytesOut (n, count) -> pr ", %s, %s" n count
| BytesPersistIn (n, _)
| BytesPersistOut (n, _) -> pr ", %s_buf->data, %s_buf->len" n n
- | Callback (n, _) | CallbackPersist (n, _) -> pr ", %s_%s_wrapper" name n
| Flags n -> pr ", %s_u32" n
| Int n -> pr ", %s" n
| Int64 n -> pr ", %s_i64" n
| Mutable arg -> pr ", /* XXX */ (void *) %s" (List.hd (name_of_arg arg))
- | Opaque n -> pr ", %s_data" (find_callback n)
+ | OpaqueAndCallbacks (n, cbs) | OpaqueAndCallbacksPersist (n, cbs) ->
+ pr ", %s" n;
+ List.iter (fun cb -> pr ", %s_%s_wrapper" name cb.name) cbs
| Path n -> pr ", %s" n
| SockAddrAndLen (n, _) -> pr ", /* XXX */ (void *) %s, 0" n
| String n -> pr ", %s" n
@@ -4119,12 +4127,11 @@ let print_python_binding name { args; ret } =
| Bool _
| BytesIn _
| BytesPersistIn _ | BytesPersistOut _
- | Callback _ | CallbackPersist _
| Flags _
| Int _
| Int64 _
| Mutable _
- | Opaque _
+ | OpaqueAndCallbacks _ | OpaqueAndCallbacksPersist _
| Path _
| SockAddrAndLen _
| String _
@@ -4162,15 +4169,14 @@ let print_python_binding name { args; ret } =
| Bool _ -> ()
| BytesIn (n, _) -> pr " PyBuffer_Release (&%s);\n" n
| BytesPersistIn _ | BytesOut _ | BytesPersistOut _ -> ()
- | Callback _ -> ()
- | CallbackPersist (n, _) ->
- pr " /* This ensures the callback data is freed eventually. */\n";
- pr " nbd_add_close_callback (h, free, %s_data);\n" n
| Flags _ -> ()
| Int _ -> ()
| Int64 _ -> ()
| Mutable _ -> ()
- | Opaque _ -> ()
+ | OpaqueAndCallbacks _ -> ()
+ | OpaqueAndCallbacksPersist (n, _) ->
+ pr " /* This ensures the callback data is freed eventually. */\n";
+ pr " nbd_add_close_callback (h, free, %s);\n" n
| Path n ->
pr " Py_XDECREF (py_%s);\n" n
| SockAddrAndLen _ -> ()
@@ -4312,12 +4318,13 @@ class NBD (object):
| BytesIn (n, _) | BytesPersistIn (n, _) -> n, None
| BytesPersistOut (n, _) -> n, None
| BytesOut (_, count) -> count, None
- | Callback (n, _) | CallbackPersist (n, _) -> n, None
| Flags n -> n, Some "0"
| Int n -> n, None
| Int64 n -> n, None
| Mutable arg -> List.hd (name_of_arg arg), None
- | Opaque n -> n, None
+ | OpaqueAndCallbacks (n, cbs)
+ | OpaqueAndCallbacksPersist (n, cbs) ->
+ n ^ ", " ^ String.concat ", " (List.map (fun cb -> cb.name) cbs), None
| Path n -> n, None
| SockAddrAndLen (n, _) -> n, None
| String n -> n, None
@@ -4399,16 +4406,12 @@ and ocaml_arg_to_string = function
| OCamlArg (BytesPersistIn _) -> "Buffer.t"
| OCamlArg (BytesOut _) -> "bytes"
| OCamlArg (BytesPersistOut _) -> "Buffer.t"
- | OCamlArg (Callback (_, args))
- | OCamlArg (CallbackPersist (_, args)) ->
- sprintf "(%s)"
- (ocaml_fundecl_to_string (List.map (fun a -> OCamlArg a) args)
- RErr)
| OCamlArg (Flags _) -> assert false (* see above *)
| OCamlArg (Int _) -> "int"
| OCamlArg (Int64 _) -> "int64"
| OCamlArg (Mutable arg) -> ocaml_arg_to_string (OCamlArg arg) ^ " ref"
- | OCamlArg (Opaque n) -> sprintf "'%s" n
+ | OCamlArg (OpaqueAndCallbacks _) | OCamlArg (OpaqueAndCallbacksPersist _) ->
+ sprintf "string" (* XXX not impl *)
| OCamlArg (Path _) -> "string"
| OCamlArg (SockAddrAndLen _) -> "string" (* XXX not impl *)
| OCamlArg (String _) -> "string"
@@ -4574,22 +4577,13 @@ external close : t -> unit = \"nbd_internal_ocaml_nbd_close\"
let print_ocaml_binding (name, { args; ret }) =
(* Functions with a callback parameter require special handling. *)
- let find_callback opaque_id =
- try
- List.find (
- function
- | Callback (_, args) | CallbackPersist (_, args) ->
- List.mem (Opaque opaque_id) args
- | _ -> false
- ) args
- with
- Not_found ->
- failwithf "%s: couldn't find callback associated with Opaque %s"
- name opaque_id
- in
List.iter (
function
+ | OpaqueAndCallbacks (cb_name, cbs)
+ | OpaqueAndCallbacksPersist (cb_name, cbs) ->
+ pr " /* Callbacks not implemented yet... */\n"
+ (*
| Callback (cb_name, args) | CallbackPersist (cb_name, args) ->
let argnames =
List.map (
@@ -4642,7 +4636,7 @@ let print_ocaml_binding (name, { args; ret }) =
pr " %sv = *_%s->data;\n" n n
| Mutable (Int n) ->
pr " %sv = caml_alloc_tuple (1);\n" n;
- pr " Store_field (%sv, 0, Val_int (*%s));\n" n n
+ pr " Store_field (%sv, 0, Val_int (" ^ "*%s));\n" n n
(* The following not yet implemented for callbacks XXX *)
| ArrayAndLen _ | Bool _ | BytesOut _
| BytesPersistIn _ | BytesPersistOut _
@@ -4694,7 +4688,8 @@ let print_ocaml_binding (name, { args; ret }) =
pr " caml_enter_blocking_section ();\n";
pr " return ret;\n";
pr "}\n"
- | _ -> ()
+ *)
+ | _ -> ()
) args;
(* Convert the generic args to OCaml args. *)
@@ -4760,6 +4755,7 @@ let print_ocaml_binding (name, { args; ret }) =
pr " struct nbd_buffer %s_buf = NBD_buffer_val (%sv);\n" n n;
pr " void *%s = %s_buf.data;\n" n n;
pr " size_t %s = %s_buf.len;\n" count n
+ (*
| OCamlArg (Callback (n, _)) ->
pr " /* This is safe because we only call this while this stack\n";
pr " * frame is live.\n";
@@ -4777,12 +4773,14 @@ let print_ocaml_binding (name, { args; ret }) =
pr " nbd_add_close_callback (h, nbd_internal_ocaml_free_root, %s_cb);\n"
n;
pr " const void *%s = %s_%s_wrapper;\n" n name n
+ *)
| OCamlArg (Flags _) -> assert false (* see above *)
| OCamlArg (Int n) ->
pr " int %s = Int_val (%sv);\n" n n
| OCamlArg (Int64 n) ->
pr " int64_t %s = Int64_val (%sv);\n" n n
| OCamlArg (Mutable _) -> assert false
+ (*
| OCamlArg (Opaque n) ->
(match find_callback n with
| Callback (cb_name, _) ->
@@ -4801,6 +4799,9 @@ let print_ocaml_binding (name, { args; ret }) =
pr " nbd_add_close_callback (h, nbd_internal_ocaml_free_root, %s_data);\n" n
| _ -> assert false
)
+ *)
+ | OCamlArg (OpaqueAndCallbacks _) | OCamlArg (OpaqueAndCallbacksPersist _) ->
+ pr " /* callbacks not implemented yet */\n"
| OCamlArg (Path n) | OCamlArg (String n) ->
pr " const char *%s = String_val (%sv);\n" n n
| OCamlArg (SockAddrAndLen (n, len)) ->
@@ -4818,6 +4819,7 @@ let print_ocaml_binding (name, { args; ret }) =
) oargs;
(* Create wrapper data for callbacks. *)
+ (*
List.iter (
function
| OCamlArg (Opaque n) ->
@@ -4836,6 +4838,7 @@ let print_ocaml_binding (name, { args; ret }) =
)
| _ -> ()
) oargs;
+ *)
let errcode =
match ret with
@@ -4877,13 +4880,12 @@ let print_ocaml_binding (name, { args; ret }) =
| OCamlArg (BytesPersistIn _)
| OCamlArg (BytesOut _)
| OCamlArg (BytesPersistOut _)
- | OCamlArg (Callback _)
- | OCamlArg (CallbackPersist _)
| OCamlArg (Flags _)
| OCamlArg (Int _)
| OCamlArg (Int64 _)
| OCamlArg (Mutable _)
- | OCamlArg (Opaque _)
+ | OCamlArg (OpaqueAndCallbacks _)
+ | OCamlArg (OpaqueAndCallbacksPersist _)
| OCamlArg (Path _)
| OCamlArg (String _)
| OCamlArg (SockAddrAndLen _)
--
2.20.1
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