LIRC libraries
LinuxInfraredRemoteControl
drv_admin.c
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1 
10 #ifdef HAVE_CONFIG_H
11 # include <config.h>
12 #endif
13 
14 #include <stdio.h>
15 #include <dirent.h>
16 #include <dlfcn.h>
17 
18 #include "lirc/driver.h"
19 #include "lirc/drv_admin.h"
20 #include "lirc/lirc_options.h"
21 #include "lirc_log.h"
22 
23 #include "driver.h"
24 
25 static const logchannel_t logchannel = LOG_LIB;
26 
27 static const char* const PLUGIN_FILE_EXTENSION = "so";
28 
29 
31 #define MAX_PLUGINS 256
32 
33 extern struct driver drv;
36 typedef struct {
37  char* array[MAX_PLUGINS];
38  int size;
39 } char_array;
40 
42 static void* last_plugin = NULL;
43 
45 const struct driver drv_null = {
46  .name = "null",
47  .device = "/dev/null",
48  .features = 0,
49  .send_mode = 0,
50  .rec_mode = 0,
51  .code_length = 0,
52  .init_func = NULL,
53  .deinit_func = NULL,
54  .send_func = NULL,
55  .rec_func = NULL,
56  .decode_func = NULL,
57  .readdata = NULL,
58  .drvctl_func = default_drvctl,
59  .open_func = default_open,
60  .close_func = default_close,
61  .api_version = 2,
62  .driver_version = "0.9.2"
63 };
64 
65 
71 static int ends_with_so(const char* str)
72 {
73  char* dot = strrchr(str, '.');
74 
75  return (NULL == dot) ? 0 : strcmp(dot + 1, PLUGIN_FILE_EXTENSION) == 0;
76 }
77 
78 
80 static int line_cmp(const void* arg1, const void* arg2)
81 {
82  return strcmp(*(const char**)arg1, *(const char**)arg2);
83 }
84 
85 
87 static struct driver* add_hw_name(struct driver* hw, void* arg)
88 {
89  char_array* a = (char_array*)arg;
90 
91  if (a->size >= MAX_PLUGINS) {
92  log_error("Too many plugins(%d)", MAX_PLUGINS);
93  return hw;
94  }
95  a->array[a->size] = strdup(hw->name);
96  a->size += 1;
97  return NULL;
98 }
99 
100 
101 static struct driver* match_hw_name(struct driver* drv, void* name)
102 {
103 // drv_guest_func. Returns hw if hw->name == name, else NULL.
104  if (drv == (struct driver*)NULL || name == NULL)
105  return (struct driver*)NULL;
106  if (strcasecmp(drv->name, (char*)name) == 0)
107  return drv;
108  return (struct driver*)NULL;
109 }
110 
111 
112 static struct driver*
113 visit_plugin(const char* path, drv_guest_func func, void* arg)
114 {
115 // Apply func(hw, arg) for all drivers found in plugin on path.
116  struct driver** drivers;
117  struct driver* result = (struct driver*)NULL;
118 
119  (void)dlerror();
120  if (last_plugin != NULL)
121  dlclose(last_plugin);
122  last_plugin = dlopen(path, RTLD_NOW);
123  if (last_plugin == NULL) {
124  log_error(dlerror());
125  return result;
126  }
127  drivers = (struct driver**)dlsym(last_plugin, "hardwares");
128  if (drivers == (struct driver**)NULL) {
129  log_warn("No hardwares entrypoint found in %s", path);
130  } else {
131  for (; *drivers; drivers++) {
132  if ((*drivers)->name == NULL) {
133  log_warn("No driver name in %s", path);
134  continue;
135  }
136  result = (*func)(*drivers, arg);
137  if (result != (struct driver*)NULL)
138  break;
139  }
140  }
141  return result;
142 }
143 
144 
145 /* Apply plugin_guest(path, drv_guest, arg) to all so-files in dir. */
146 static struct driver* for_each_plugin_in_dir(const char* dirpath,
147  plugin_guest_func plugin_guest,
148  drv_guest_func drv_guest,
149  void* arg)
150 {
151  DIR* dir;
152  struct dirent* ent;
153  struct driver* result = (struct driver*)NULL;
154  char path[128];
155  char buff[128];
156 
157  dir = opendir(dirpath);
158  if (dir == NULL) {
159  log_info("Cannot open plugindir %s", dirpath);
160  return (struct driver*)NULL;
161  }
162  while ((ent = readdir(dir)) != NULL) {
163  if (!ends_with_so(ent->d_name))
164  continue;
165  strncpy(buff, dirpath, sizeof(buff) - 1);
166  if (buff[strlen(buff) - 1] == '/')
167  buff[strlen(buff) - 1] = '\0';
168  snprintf(path, sizeof(path),
169  "%s/%s", buff, ent->d_name);
170  result = plugin_guest(path, drv_guest, arg);
171  if (result != (struct driver*)NULL)
172  break;
173  }
174  closedir(dir);
175  return result;
176 }
177 
178 
179 static struct driver* for_each_path(plugin_guest_func plg_guest,
180  drv_guest_func drv_guest,
181  void* arg,
182  const char* pluginpath_arg)
183 {
184  const char* pluginpath;
185  char* tmp_path;
186  char* s;
187  struct driver* result = (struct driver*)NULL;
188 
189  if (pluginpath_arg == NULL) {
190  pluginpath = ciniparser_getstring(lirc_options,
191  "lircd:plugindir",
192  getenv(PLUGINDIR_VAR));
193  if (pluginpath == NULL)
194  pluginpath = PLUGINDIR;
195  } else {
196  pluginpath = pluginpath_arg;
197  }
198  if (strchr(pluginpath, ':') == (char*)NULL) {
199  return for_each_plugin_in_dir(pluginpath,
200  plg_guest,
201  drv_guest,
202  arg);
203  }
204  tmp_path = alloca(strlen(pluginpath) + 1);
205  strncpy(tmp_path, pluginpath, strlen(pluginpath) + 1);
206  for (s = strtok(tmp_path, ":"); s != NULL; s = strtok(NULL, ":")) {
207  result = for_each_plugin_in_dir(s,
208  plg_guest,
209  drv_guest,
210  arg);
211  if (result != (struct driver*)NULL)
212  break;
213  }
214  return result;
215 }
216 
217 
219  void* arg,
220  const char* pluginpath)
221 {
222  return for_each_path(visit_plugin, func, arg, pluginpath);
223 }
224 
225 
227  void* arg,
228  const char* pluginpath)
229 {
230  for_each_path(plugin_guest, NULL, arg, pluginpath);
231 }
232 
233 
238 void hw_print_drivers(FILE* file)
239 {
240  char_array names;
241  int i;
242 
243  names.size = 0;
244  if (for_each_driver(add_hw_name, (void*)&names, NULL) != NULL) {
245  fprintf(stderr, "Too many plugins (%d)\n", MAX_PLUGINS);
246  return;
247  }
248  qsort(names.array, names.size, sizeof(char*), line_cmp);
249  for (i = 0; i < names.size; i += 1) {
250  fprintf(file, "%s\n", names.array[i]);
251  free(names.array[i]);
252  }
253 }
254 
255 
256 int hw_choose_driver(const char* name)
257 {
258  struct driver* found;
259 
260  if (name == NULL) {
261  memcpy(&drv, &drv_null, sizeof(struct driver));
262  return 0;
263  }
264  if (strcasecmp(name, "dev/input") == 0)
265  /* backwards compatibility */
266  name = "devinput";
267  found = for_each_driver(match_hw_name, (void*)name, NULL);
268  if (found != (struct driver*)NULL) {
269  memcpy(&drv, found, sizeof(struct driver));
270  return 0;
271  }
272  return -1;
273 }
const char * ciniparser_getstring(dictionary *d, const char *key, char *def)
Get the string associated to a key.
Definition: ciniparser.c:286
int default_close(void)
Definition: driver.c:79
struct driver *(* plugin_guest_func)(const char *, drv_guest_func, void *)
Definition: drv_admin.h:41
Logging functionality.
Interface to the userspace drivers.
#define log_warn(fmt,...)
Definition: lirc_log.h:109
#define MAX_PLUGINS
Definition: drv_admin.c:31
const struct driver drv_null
Definition: drv_admin.c:45
logchannel_t
Definition: lirc_log.h:53
#define PLUGINDIR
Definition: lirc_config.h:80
#define log_error(fmt,...)
Definition: lirc_log.h:104
void for_each_plugin(plugin_guest_func plugin_guest, void *arg, const char *pluginpath)
Definition: drv_admin.c:226
void hw_print_drivers(FILE *file)
Prints all drivers known to the system to the file given as argument.
Definition: drv_admin.c:238
struct driver drv
Definition: driver.c:22
struct driver *(* drv_guest_func)(struct driver *, void *)
Definition: drv_admin.h:32
#define PLUGINDIR_VAR
Definition: lirc_config.h:101
int default_drvctl(unsigned int fd, void *arg)
Definition: driver.c:84
struct driver * for_each_driver(drv_guest_func func, void *arg, const char *pluginpath)
Definition: drv_admin.c:218
Definition: driver.h:127
int hw_choose_driver(const char *name)
Definition: drv_admin.c:256
const char * name
Definition: driver.h:219
int default_open(const char *path)
Definition: driver.c:64
#define log_info(fmt,...)
Definition: lirc_log.h:114