2 * This file is part of the sigrok project.
4 * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 #include <sigrokdecode.h> /* First, so we avoid a _POSIX_C_SOURCE warning. */
27 /* Re-define some string functions for Python >= 3.0. */
28 #if PY_VERSION_HEX >= 0x03000000
29 #define PyString_AsString PyBytes_AsString
30 #define PyString_FromString PyBytes_FromString
31 #define PyString_Check PyBytes_Check
34 /* The list of protocol decoders. */
35 GSList *list_pds = NULL;
38 * Here's a quick overview of Python/C API reference counting.
40 * Check the Python/C API docs for what type of reference a function returns.
42 * - If it returns a "new reference", you're responsible to Py_XDECREF() it.
44 * - If it returns a "borrowed reference", you MUST NOT Py_XDECREF() it.
46 * - If a function "steals" a reference, you no longer are responsible for
47 * Py_XDECREF()ing it (someone else will do it for you at some point).
51 * Initialize libsigrokdecode.
53 * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
55 int sigrokdecode_init(void)
61 /* Py_Initialize() returns void and usually cannot fail. */
64 /* Add search directory for the protocol decoders. */
65 /* FIXME: Check error code. */
66 /* FIXME: What happens if this function is called multiple times? */
67 PyRun_SimpleString("import sys;"
68 "sys.path.append(r'" DECODERS_DIR "');");
70 if (!(dir = opendir(DECODERS_DIR)))
71 return SIGROKDECODE_ERR_DECODERS_DIR;
73 while ((dp = readdir(dir)) != NULL) {
74 if (!g_str_has_suffix(dp->d_name, ".py"))
76 /* For now use the filename (without .py) as decoder name. */
77 if ((tmp = g_strndup(dp->d_name, strlen(dp->d_name) - 3)))
78 list_pds = g_slist_append(list_pds, tmp);
82 return SIGROKDECODE_OK;
86 * Returns the list of supported/loaded protocol decoders.
88 * This is a GSList containing the names of the decoders as strings.
90 * @return List of decoders, NULL if none are supported or loaded.
92 GSList *sigrokdecode_list_decoders(void)
98 * Helper function to handle Python strings.
100 * TODO: @param entries.
102 * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
103 * The 'outstr' argument points to a malloc()ed string upon success.
105 static int h_str(PyObject *py_res, PyObject *py_func, PyObject *py_mod,
106 const char *key, char **outstr)
112 py_str = PyMapping_GetItemString(py_res, (char *)key);
113 if (!py_str || !PyString_Check(py_str)) {
114 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
115 goto err_h_decref_func;
119 * PyString_AsString()'s returned string refers to an internal buffer
120 * (not a copy), i.e. the data must not be modified, and the memory
121 * must not be free()'d.
123 if (!(str = PyString_AsString(py_str))) {
124 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
125 goto err_h_decref_str;
128 if (!(*outstr = strdup(str))) {
129 ret = SIGROKDECODE_ERR_MALLOC;
130 goto err_h_decref_str;
135 return SIGROKDECODE_OK;
144 if (PyErr_Occurred())
145 PyErr_Print(); /* Returns void. */
155 * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
157 int sigrokdecode_load_decoder(const char *name,
158 struct sigrokdecode_decoder **dec)
160 struct sigrokdecode_decoder *d;
161 PyObject *py_name, *py_mod, *py_func, *py_res /* , *py_tuple */;
164 /* Get the name of the decoder module as Python string. */
165 if (!(py_name = PyString_FromString(name))) { /* NEWREF */
166 PyErr_Print(); /* Returns void. */
167 return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
170 /* "Import" the Python module. */
171 if (!(py_mod = PyImport_Import(py_name))) { /* NEWREF */
172 PyErr_Print(); /* Returns void. */
174 return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
178 /* Get the 'register' function name as Python callable object. */
179 py_func = PyObject_GetAttrString(py_mod, "register"); /* NEWREF */
180 if (!py_func || !PyCallable_Check(py_func)) {
181 if (PyErr_Occurred())
182 PyErr_Print(); /* Returns void. */
184 return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
187 /* Call the 'register' function without arguments, get the result. */
188 if (!(py_res = PyObject_CallFunction(py_func, NULL))) { /* NEWREF */
189 PyErr_Print(); /* Returns void. */
192 return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
195 if (!(d = malloc(sizeof(struct sigrokdecode_decoder))))
196 return SIGROKDECODE_ERR_MALLOC;
198 if ((r = h_str(py_res, py_func, py_mod, "id", &(d->id))) < 0)
201 if ((r = h_str(py_res, py_func, py_mod, "name", &(d->name))) < 0)
204 if ((r = h_str(py_res, py_func, py_mod, "desc", &(d->desc))) < 0)
212 /* Get the 'decode' function name as Python callable object. */
213 py_func = PyObject_GetAttrString(py_mod, "decode"); /* NEWREF */
214 if (!py_func || !PyCallable_Check(py_func)) {
215 if (PyErr_Occurred())
216 PyErr_Print(); /* Returns void. */
218 return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
221 d->py_func = py_func;
223 /* TODO: Handle inputformats, outputformats. */
227 return SIGROKDECODE_OK;
231 * Run the specified decoder function.
235 * @param inbuflen TODO
237 * @param outbuflen TODO
239 * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
241 int sigrokdecode_run_decoder(struct sigrokdecode_decoder *dec,
242 uint8_t *inbuf, uint64_t inbuflen,
243 uint8_t **outbuf, uint64_t *outbuflen)
245 PyObject *py_mod, *py_func, *py_args, *py_value, *py_res;
248 /* TODO: Use #defines for the return codes. */
250 /* Return an error upon unusable input. */
252 return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
254 return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
255 if (inbuflen == 0) /* No point in working on empty buffers. */
256 return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
258 return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
259 if (outbuflen == NULL)
260 return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
262 /* TODO: Error handling. */
263 py_mod = dec->py_mod;
265 py_func = dec->py_func;
268 /* Create a Python tuple of size 1. */
269 if (!(py_args = PyTuple_New(1))) { /* NEWREF */
270 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
271 goto err_run_decref_func;
274 /* Get the input buffer as Python "string" (byte array). */
275 /* TODO: int vs. uint64_t for 'inbuflen'? */
276 if (!(py_value = Py_BuildValue("s#", inbuf, inbuflen))) { /* NEWREF */
277 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
278 goto err_run_decref_args;
282 * IMPORTANT: PyTuple_SetItem() "steals" a reference to py_value!
283 * That means we are no longer responsible for Py_XDECREF()'ing it.
284 * It will automatically be free'd when the 'py_args' tuple is free'd.
286 if (PyTuple_SetItem(py_args, 0, py_value) != 0) { /* STEAL */
287 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
288 Py_XDECREF(py_value); /* TODO: Ref. stolen upon error? */
289 goto err_run_decref_args;
292 if (!(py_res = PyObject_CallObject(py_func, py_args))) { /* NEWREF */
293 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
294 goto err_run_decref_args;
297 if ((r = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
298 (Py_ssize_t *)outbuflen))) {
299 ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
301 goto err_run_decref_args;
304 ret = SIGROKDECODE_OK;
315 if (PyErr_Occurred())
316 PyErr_Print(); /* Returns void. */
322 * Shutdown libsigrokdecode.
324 * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
326 int sigrokdecode_shutdown(void)
328 /* Py_Finalize() returns void, any finalization errors are ignored. */
331 return SIGROKDECODE_OK;