]> sigrok.org Git - libsigrokdecode.git/blame - decoder.c
srd: decoder class structure check belongs in module loader
[libsigrokdecode.git] / decoder.c
CommitLineData
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1/*
2 * This file is part of the sigrok project.
3 *
4 * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
5 * Copyright (C) 2011 Bert Vermeulen <bert@biot.com>
6 *
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21#include "config.h"
73191416 22#include "sigrokdecode.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
15969949 23#include "sigrokdecode-internal.h"
eb2bbd66 24#include <glib.h>
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25
26/* The list of protocol decoders. */
e5080882 27GSList *pd_list = NULL;
b2c19614 28
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29/* lives in module_sigrokdecode.c */
30extern PyObject *mod_sigrokdecode;
31
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32
33/**
34 * Returns the list of supported/loaded protocol decoders.
35 *
36 * This is a GSList containing the names of the decoders as strings.
37 *
38 * @return List of decoders, NULL if none are supported or loaded.
39 */
40GSList *srd_list_decoders(void)
41{
42
e5080882 43 return pd_list;
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44}
45
46
47/**
48 * Get the decoder with the specified ID.
49 *
50 * @param id The ID string of the decoder to return.
51 * @return The decoder with the specified ID, or NULL if not found.
52 */
53struct srd_decoder *srd_get_decoder_by_id(const char *id)
54{
55 GSList *l;
56 struct srd_decoder *dec;
57
58 for (l = srd_list_decoders(); l; l = l->next) {
59 dec = l->data;
60 if (!strcmp(dec->id, id))
61 return dec;
62 }
63
64 return NULL;
65}
66
67
68/**
64c29e28 69 * Load a protocol decoder module into the embedded Python interpreter.
b2c19614 70 *
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71 * @param name The module name to be loaded.
72 * @param dec Pointer to the struct srd_decoder filled with the loaded module.
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73 *
74 * @return SRD_OK upon success, a (negative) error code otherwise.
75 */
76int srd_load_decoder(const char *name, struct srd_decoder **dec)
77{
11ea8ae1 78 PyObject *py_basedec, *py_method, *py_attr, *py_annlist, *py_ann;
b2c19614 79 struct srd_decoder *d;
451680f1 80 int alen, ret, i;
15969949 81 char **ann;
b2c19614 82
11ea8ae1 83 py_basedec = py_method = py_attr = NULL;
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84
85 srd_dbg("decoder: %s: loading module '%s'", __func__, name);
b2c19614 86
451680f1 87 if (!(d = g_try_malloc0(sizeof(struct srd_decoder)))) {
64c29e28 88 srd_err("decoder: %s: d malloc failed", __func__);
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89 ret = SRD_ERR_MALLOC;
90 goto err_out;
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91 }
92
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93 ret = SRD_ERR_PYTHON;
94
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95 /* Import the Python module. */
96 if (!(d->py_mod = PyImport_ImportModule(name))) {
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97 /* TODO: Report exception message/traceback to err/dbg. */
98 srd_warn("decoder: %s: import of '%s' failed", __func__, name);
99 PyErr_Print();
451680f1 100 PyErr_Clear();
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101 goto err_out;
102 }
b2c19614 103
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104 /* Get the 'Decoder' class as Python object. */
105 if (!(d->py_dec = PyObject_GetAttrString(d->py_mod, "Decoder"))) {
106 /* This generated an AttributeError exception. */
64c29e28 107 PyErr_Print();
451680f1 108 PyErr_Clear();
1d552cd3 109 srd_err("Decoder class not found in protocol decoder %s", name);
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110 goto err_out;
111 }
b2c19614 112
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113 if (!(py_basedec = PyObject_GetAttrString(mod_sigrokdecode, "Decoder"))) {
114 srd_dbg("sigrokdecode module not loaded");
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115 goto err_out;
116 }
b2c19614 117
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118 if (!PyObject_IsSubclass(d->py_dec, py_basedec)) {
119 srd_err("Decoder class in protocol decoder module %s is not "
120 "a subclass of sigrokdecode.Decoder", name);
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121 goto err_out;
122 }
123 Py_DecRef(py_basedec);
b2c19614 124
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125 /* Check for a proper start() method. */
126 if (!PyObject_HasAttrString(d->py_dec, "start")) {
127 srd_err("Protocol decoder %s has no start() method Decoder "
128 "class.", name);
129 goto err_out;
130 }
131 py_method = PyObject_GetAttrString(d->py_dec, "start");
132 if (!PyFunction_Check(py_method)) {
133 srd_err("Protocol decoder %s Decoder class attribute 'start'"
134 "is not a method.", name);
135 goto err_out;
136 }
137 Py_DecRef(py_method);
138
139 /* Check for a proper decode() method. */
140 if (!PyObject_HasAttrString(d->py_dec, "decode")) {
141 srd_err("Protocol decoder %s has no decode() method Decoder "
142 "class.", name);
143 goto err_out;
144 }
145 py_method = PyObject_GetAttrString(d->py_dec, "decode");
146 if (!PyFunction_Check(py_method)) {
147 srd_err("Protocol decoder %s Decoder class attribute 'decode' "
148 "is not a method.", name);
149 goto err_out;
150 }
151 Py_DecRef(py_method);
152
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153 /* If present, options must be a dictionary. */
154 if (PyObject_HasAttrString(d->py_dec, "options")) {
155 py_attr = PyObject_GetAttrString(d->py_dec, "options");
156 if (!PyDict_Check(py_attr)) {
157 srd_err("Protocol decoder %s options attribute is not "
158 "a dictionary.", d->name);
159 goto err_out;
160 }
161 Py_DecRef(py_attr);
162 }
163
21481b66 164 if (py_attr_as_str(d->py_dec, "id", &(d->id)) != SRD_OK)
451680f1 165 goto err_out;
b2c19614 166
21481b66 167 if (py_attr_as_str(d->py_dec, "name", &(d->name)) != SRD_OK)
451680f1 168 goto err_out;
b2c19614 169
21481b66 170 if (py_attr_as_str(d->py_dec, "longname", &(d->longname)) != SRD_OK)
451680f1 171 goto err_out;
b2c19614 172
21481b66 173 if (py_attr_as_str(d->py_dec, "desc", &(d->desc)) != SRD_OK)
451680f1 174 goto err_out;
b2c19614 175
21481b66 176 if (py_attr_as_str(d->py_dec, "license", &(d->license)) != SRD_OK)
451680f1 177 goto err_out;
b2c19614 178
451680f1 179 /* TODO: Handle inputformats, outputformats. */
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180 d->inputformats = NULL;
181 d->outputformats = NULL;
182
15969949 183 /* Convert class annotation attribute to GSList of **char */
e97b6ef5 184 d->annotations = NULL;
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185 if (PyObject_HasAttrString(d->py_dec, "annotations")) {
186 py_annlist = PyObject_GetAttrString(d->py_dec, "annotations");
15969949 187 if (!PyList_Check(py_annlist)) {
e97b6ef5 188 srd_err("Protocol decoder module %s annotations should be a list", name);
451680f1 189 goto err_out;
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190 }
191 alen = PyList_Size(py_annlist);
192 for (i = 0; i < alen; i++) {
193 py_ann = PyList_GetItem(py_annlist, i);
194 if (!PyList_Check(py_ann) || PyList_Size(py_ann) != 2) {
195 srd_err("Protocol decoder module %s annotation %d should be a list with two elements",
196 name, i+1);
451680f1 197 goto err_out;
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198 }
199
451680f1 200 if (py_strlist_to_char(py_ann, &ann) != SRD_OK) {
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201 goto err_out;
202 }
e97b6ef5 203 d->annotations = g_slist_append(d->annotations, ann);
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204 }
205 }
206
b2c19614 207 *dec = d;
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208 ret = SRD_OK;
209
210err_out:
211 if (ret != SRD_OK) {
1d552cd3 212 Py_XDECREF(py_method);
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213 Py_XDECREF(py_basedec);
214 Py_XDECREF(d->py_dec);
215 Py_XDECREF(d->py_mod);
216 g_free(d);
217 }
b2c19614 218
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219 return ret;
220}
221
222char *srd_decoder_doc(struct srd_decoder *dec)
223{
e7edca07 224 PyObject *py_str;
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225 char *doc;
226
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227 if (!PyObject_HasAttrString(dec->py_mod, "__doc__"))
228 return NULL;
229
230 if (!(py_str = PyObject_GetAttrString(dec->py_mod, "__doc__"))) {
231 PyErr_Clear();
232 return NULL;
233 }
234
451680f1 235 doc = NULL;
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236 if (py_str != Py_None)
237 py_str_as_str(py_str, &doc);
238 Py_DecRef(py_str);
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239
240 return doc;
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241}
242
243
244/**
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245 * Unload decoder module.
246 *
247 * @param dec The decoder struct to be unloaded.
248 *
249 * @return SRD_OK upon success, a (negative) error code otherwise.
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250 */
251int srd_unload_decoder(struct srd_decoder *dec)
252{
451680f1 253
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254 g_free(dec->id);
255 g_free(dec->name);
b231546d 256 g_free(dec->longname);
b2c19614 257 g_free(dec->desc);
b231546d 258 g_free(dec->license);
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259
260 /* TODO: Free everything in inputformats and outputformats. */
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261 if (dec->inputformats != NULL)
262 g_slist_free(dec->inputformats);
263 if (dec->outputformats != NULL)
264 g_slist_free(dec->outputformats);
265
451680f1 266 Py_XDECREF(dec->py_dec);
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267 Py_XDECREF(dec->py_mod);
268
269 /* TODO: (g_)free dec itself? */
270
271 return SRD_OK;
272}
273
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274int srd_load_all_decoders(void)
275{
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276 GDir *dir;
277 GError *error;
278 struct srd_decoder *dec;
b2c19614 279 int ret;
eb2bbd66 280 const gchar *direntry;
b2c19614 281 char *decodername;
b2c19614 282
eb2bbd66 283 if (!(dir = g_dir_open(DECODERS_DIR, 0, &error))) {
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284 return SRD_ERR_DECODERS_DIR;
285 }
286
eb2bbd66 287 while ((direntry = g_dir_read_name(dir)) != NULL) {
64c29e28 288 /* The decoder name is the PD directory name (e.g. "i2c"). */
eb2bbd66 289 decodername = g_strdup(direntry);
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290
291 /* TODO: Error handling. Use g_try_malloc(). */
292 if (!(dec = malloc(sizeof(struct srd_decoder)))) {
293 Py_Finalize(); /* Returns void. */
294 return SRD_ERR_MALLOC;
295 }
296
297 /* Load the decoder. */
298 /* TODO: Warning if loading fails for a decoder. */
299 if ((ret = srd_load_decoder(decodername, &dec)) == SRD_OK) {
300 /* Append it to the list of supported/loaded decoders. */
e5080882 301 pd_list = g_slist_append(pd_list, dec);
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302 }
303 }
eb2bbd66 304 g_dir_close(dir);
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305
306 return SRD_OK;
307}
308
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309/**
310 * TODO
311 */
312int srd_unload_all_decoders(void)
313{
314 GSList *l;
315 struct srd_decoder *dec;
316
317 for (l = srd_list_decoders(); l; l = l->next) {
318 dec = l->data;
319 /* TODO: Error handling. */
320 srd_unload_decoder(dec);
321 }
322
323 return SRD_OK;
324}
325
326
327