Merge branch 'master' into my-osx
[paraslash.git] / stat.c
1 /*
2 * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /**
20 * \file stat.c functions used for sending/receiving the status of para_server
21 * and para_audiod
22 */
23 #include "para.h"
24 #include "close_on_fork.h"
25 #include "list.h"
26 #include "error.h"
27 #include "string.h"
28 #include "fd.h"
29
30 /** the maximal number of simultaneous connections */
31 #define MAX_STAT_CLIENTS 50
32
33 /**
34 * The structure associated with a connected client that sent the 'stat' command
35 *
36 *
37 * A status client is identified by its file descriptor. para_audiod
38 * keeps a list of connected status clients.
39 */
40 struct stat_client {
41 /**
42 *
43 *
44 * the stat client's file descriptor
45 */
46 int fd;
47 long unsigned item_mask;
48 /**
49 *
50 * its entry in the list of stat clients
51 */
52 struct list_head node;
53 };
54
55 static struct list_head client_list;
56 static int initialized;
57 static int num_clients;
58
59 /**
60 * the list of all status items sent by para_server/para_audiod
61 */
62 const char *status_item_list[NUM_STAT_ITEMS] = {
63 [SI_STATUS_BAR] = "status_bar",
64 [SI_STATUS] = "status",
65 [SI_NUM_PLAYED] = "num_played",
66
67 [SI_MTIME] = "mtime",
68 [SI_LENGTH_MIN] = "length_min",
69 [SI_LENGTH_SEC] = "length_sec",
70
71 [SI_FILE_SIZE] = "file_size",
72 [SI_STATUS_FLAGS] = "status_flags",
73 [SI_FORMAT] = "format",
74
75 [SI_SCORE] = "score",
76 [SI_AUDIO_INFO1] = "audio_file_info1",
77 [SI_AUDIO_INFO2] = "audio_file_info2",
78
79 [SI_AUDIO_INFO3] = "audio_file_info3",
80 [SI_DBINFO1] = "dbinfo1",
81 [SI_DBINFO2] = "dbinfo2",
82
83 [SI_DBINFO3] = "dbinfo3",
84 [SI_DECODER_FLAGS] = "decoder_flags",
85 [SI_AUDIOD_STATUS] = "audiod_status",
86
87 [SI_PLAY_TIME] = "play_time",
88 [SI_UPTIME] = "uptime",
89 [SI_OFFSET] = "offset",
90
91 [SI_LENGTH] = "length",
92 [SI_STREAM_START] = "stream_start",
93 [SI_CURRENT_TIME] = "current_time",
94
95 [SI_AUDIOD_UPTIME] = "audiod_uptime",
96 [SI_SELECTOR] = "dbtool"
97 };
98 #define FOR_EACH_STAT_ITEM(i) for (i = 0; i < NUM_STAT_ITEMS; i++)
99
100 static void dump_stat_client_list(void)
101 {
102 struct stat_client *sc;
103
104 if (!initialized)
105 return;
106 list_for_each_entry(sc, &client_list, node)
107 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
108 }
109 /**
110 * add a status client to the list
111 *
112 * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
113 * the number of connected clients exceeds #MAX_STAT_CLIENTS
114 */
115 int stat_client_add(int fd, long unsigned mask)
116 {
117 struct stat_client *new_client;
118
119 if (num_clients >= MAX_STAT_CLIENTS) {
120 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
121 MAX_STAT_CLIENTS);
122 return -E_TOO_MANY_CLIENTS;
123 }
124 if (!initialized) {
125 INIT_LIST_HEAD(&client_list);
126 initialized = 1;
127 }
128 PARA_INFO_LOG("adding client on fd %d\n", fd);
129 new_client = para_malloc(sizeof(struct stat_client));
130 new_client->fd = fd;
131 new_client->item_mask = mask;
132 list_add(&new_client->node, &client_list);
133 dump_stat_client_list();
134 num_clients++;
135 return 1;
136 }
137 /**
138 * write a message to all connected status clients
139 *
140 * \param msg a \p NULL terminated buffer
141 * \param itemnum The number of the status item of \a msg
142 *
143 * On write errors, remove the status client from the client list and close its
144 * file descriptor.
145 */
146 void stat_client_write(char *msg, int itemnum)
147 {
148 struct stat_client *sc, *tmp;
149 ssize_t len;
150 struct timeval tv = {0 , 0};
151
152 if (!initialized)
153 return;
154 len = strlen(msg);
155 list_for_each_entry_safe(sc, tmp, &client_list, node) {
156 int fd = sc->fd, ret;
157 fd_set wfds;
158
159 if (!((1 << itemnum) & sc->item_mask))
160 continue;
161 FD_ZERO(&wfds);
162 FD_SET(fd, &wfds);
163 // PARA_DEBUG_LOG("%s: p=%lx\n", __func__, (long)p);
164 ret = para_select(fd + 1, NULL, &wfds, &tv);
165 if (ret > 0) {
166 ret = write(fd, msg, len);
167 PARA_DEBUG_LOG("dumped %s to fd %d, ret = %d\n", msg, fd, ret);
168 if (ret == len )
169 continue;
170 }
171 /* write error or fd not ready for writing */
172 close(fd);
173 num_clients--;
174 PARA_INFO_LOG("deleting client on fd %d\n", fd);
175 list_del(&sc->node);
176 free(sc);
177 dump_stat_client_list();
178 }
179 PARA_DEBUG_LOG("%d client(s)\n", num_clients);
180 }
181
182 /**
183 * send empty status list
184 *
185 * Send to each connected client the full status item list
186 * with empty values.
187 */
188 void dump_empty_status(void)
189 {
190 int i;
191
192 if (!initialized)
193 return;
194 FOR_EACH_STAT_ITEM(i) {
195 char *tmp = make_message("%s:\n", status_item_list[i]);
196 stat_client_write(tmp, i);
197 free(tmp);
198 }
199 }
200
201 /**
202 * check if string is a known status item.
203 *
204 * \param item buffer containing the text to check
205 *
206 * \return If \a item is a valid status item, the number of that status item is
207 * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
208 */
209 int stat_item_valid(const char *item)
210 {
211 int i;
212 if (!item || !*item) {
213 PARA_ERROR_LOG("%s\n", "no item");
214 return -E_UNKNOWN_STAT_ITEM;
215 }
216 FOR_EACH_STAT_ITEM(i)
217 if (!strcmp(status_item_list[i], item))
218 return i;
219 return -E_UNKNOWN_STAT_ITEM;
220 }
221
222 /**
223 * check if line starts with known status item.
224 *
225 * \param line buffer containing the line
226 *
227 * \return If the beginning of \a line matches any paraslash status item and is
228 * followed by a colon, the number of that status item is returned. Otherwise,
229 * this function returns \p -E_UNKNOWN_STAT_ITEM.
230 */
231 int stat_line_valid(const char *line)
232 {
233 int i;
234 size_t line_len;
235
236 if (!line || !*line)
237 return -E_UNKNOWN_STAT_ITEM;
238 line_len = strlen(line);
239 FOR_EACH_STAT_ITEM(i) {
240 const char *s = status_item_list[i];
241 size_t item_len = strlen(s);
242
243 if (line_len > item_len && line[item_len] == ':' &&
244 !strncmp(line, s, item_len))
245 return i;
246 }
247 return -E_UNKNOWN_STAT_ITEM;
248 }
249
250 /**
251 * call a custom function for each complete line
252 *
253 * \param buf the buffer containing data seperated by newlines
254 * \param n the number of bytes in \a buf
255 * \param line_handler the custom function
256 *
257 * If \a line_handler is \p NULL, return number of complete lines in buf.
258 * Otherwise, call \a line_handler for each complete line. The rest of the
259 * buffer (last chunk containing incomplete line is moved to the beginning of
260 * the buffer.
261 *
262 * \return If line_handler is not NULL, this function returns the number
263 * of bytes not handled to \a line_handler.
264 */
265 unsigned for_each_line(char *buf, int n, void (*line_handler)(char *))
266 {
267 char *start = buf, *end;
268 int i, num_lines = 0;
269
270 // PARA_INFO_LOG("buf: %s", buf);
271 while (start < buf + n) {
272 char *next_null;
273 char *next_cr;
274
275 next_cr = memchr(start, '\n', buf + n - start);
276 next_null = memchr(start, '\0', buf + n - start);
277 if (!next_cr && !next_null)
278 break;
279 if (next_cr && next_null) {
280 end = next_cr < next_null? next_cr : next_null;
281 } else if (next_null) {
282 end = next_null;
283 } else
284 end = next_cr;
285 num_lines++;
286 if (line_handler) {
287 *end = '\0';
288 // PARA_INFO_LOG("calling line handler: %s\n", start);
289 line_handler(start);
290 start = ++end;
291 } else
292 start = ++end;
293 }
294 if (!line_handler)
295 return num_lines;
296 i = buf + n - start;
297 if (i && i != n)
298 memmove(buf, start, i);
299 return i;
300 }
301