Replace status item SELECTOR by IMAGE_ID.
[paraslash.git] / stat.c
1 /*
2 * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /**
8 * \file stat.c functions used for sending/receiving the status of para_server
9 * and para_audiod
10 */
11
12
13 #include <sys/types.h>
14 #include <dirent.h>
15
16 #include "para.h"
17 #include "close_on_fork.h"
18 #include "list.h"
19 #include "error.h"
20 #include "string.h"
21 #include "fd.h"
22
23 /** the maximal number of simultaneous connections */
24 #define MAX_STAT_CLIENTS 50
25
26 /**
27 * describes a status client of para_audiod
28 *
29 * There's one such structure per audiod client that sent the 'stat' command.
30 *
31 * A status client is identified by its file descriptor. para_audiod
32 * keeps a list of connected status clients.
33 */
34 struct stat_client {
35 /** the stat client's file descriptor */
36 int fd;
37 /** bitmask of those status items the client is interested in */
38 long unsigned item_mask;
39 /** its entry in the list of stat clients */
40 struct list_head node;
41 };
42
43 static struct list_head client_list;
44 static int initialized;
45 static int num_clients;
46
47 /** The list of all status items used by para_server/para_audiod. */
48 const char *status_item_list[NUM_STAT_ITEMS] = {
49 [SI_BASENAME] = "basename",
50 [SI_STATUS] = "status",
51 [SI_NUM_PLAYED] = "num_played",
52
53 [SI_MTIME] = "mtime",
54 [SI_LENGTH_MIN] = "length_min",
55 [SI_LENGTH_SEC] = "length_sec",
56
57 [SI_FILE_SIZE] = "file_size",
58 [SI_STATUS_FLAGS] = "status_flags",
59 [SI_FORMAT] = "format",
60
61 [SI_SCORE] = "score",
62 [SI_AUDIO_INFO1] = "audio_file_info1",
63 [SI_AUDIO_INFO2] = "audio_file_info2",
64
65 [SI_AUDIO_INFO3] = "audio_file_info3",
66 [SI_AFS_MODE] = "afs_mode",
67 [SI_ATTRIBUTES] = "attributes",
68
69 [SI_DIRECTORY] = "dir",
70 [SI_DECODER_FLAGS] = "decoder_flags",
71 [SI_AUDIOD_STATUS] = "audiod_status",
72
73 [SI_PLAY_TIME] = "play_time",
74 [SI_UPTIME] = "uptime",
75 [SI_OFFSET] = "offset",
76
77 [SI_LENGTH] = "length",
78 [SI_STREAM_START] = "stream_start",
79 [SI_CURRENT_TIME] = "current_time",
80
81 [SI_AUDIOD_UPTIME] = "audiod_uptime",
82 [SI_IMAGE_ID] = "image_id"
83 };
84
85 static void dump_stat_client_list(void)
86 {
87 struct stat_client *sc;
88
89 if (!initialized)
90 return;
91 list_for_each_entry(sc, &client_list, node)
92 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
93 }
94 /**
95 * add a status client to the list
96 *
97 * \param fd the file descriptor of the client
98 * \param mask bitfield of status items for this client
99 *
100 * Only those status items having the bit set in \a mask will be
101 * sent to the client.
102 *
103 * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
104 * the number of connected clients exceeds #MAX_STAT_CLIENTS.
105 */
106 int stat_client_add(int fd, long unsigned mask)
107 {
108 struct stat_client *new_client;
109
110 if (num_clients >= MAX_STAT_CLIENTS) {
111 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
112 MAX_STAT_CLIENTS);
113 return -E_TOO_MANY_CLIENTS;
114 }
115 if (!initialized) {
116 INIT_LIST_HEAD(&client_list);
117 initialized = 1;
118 }
119 PARA_INFO_LOG("adding client on fd %d\n", fd);
120 new_client = para_malloc(sizeof(struct stat_client));
121 new_client->fd = fd;
122 new_client->item_mask = mask;
123 para_list_add(&new_client->node, &client_list);
124 dump_stat_client_list();
125 num_clients++;
126 return 1;
127 }
128 /**
129 * write a message to all connected status clients
130 *
131 * \param msg a \p NULL terminated buffer
132 * \param itemnum The number of the status item of \a msg
133 *
134 * On write errors, remove the status client from the client list and close its
135 * file descriptor.
136 */
137 void stat_client_write(const char *msg, int itemnum)
138 {
139 struct stat_client *sc, *tmp;
140 size_t len = strlen(msg);
141 struct timeval tv = {0 , 0};
142
143 if (!initialized || !len)
144 return;
145 list_for_each_entry_safe(sc, tmp, &client_list, node) {
146 int fd = sc->fd, ret;
147 fd_set wfds;
148
149 if (!((1 << itemnum) & sc->item_mask))
150 continue;
151 FD_ZERO(&wfds);
152 FD_SET(fd, &wfds);
153 // PARA_DEBUG_LOG("%s: p=%lx\n", __func__, (long)p);
154 ret = para_select(fd + 1, NULL, &wfds, &tv);
155 if (ret > 0) {
156 ret = write(fd, msg, len);
157 PARA_DEBUG_LOG("dumped %s to fd %d, ret = %d\n", msg, fd, ret);
158 if (ret == len )
159 continue;
160 }
161 /* write error or fd not ready for writing */
162 close(fd);
163 num_clients--;
164 PARA_INFO_LOG("deleting client on fd %d\n", fd);
165 list_del(&sc->node);
166 free(sc);
167 dump_stat_client_list();
168 }
169 PARA_DEBUG_LOG("%d client(s)\n", num_clients);
170 }
171
172 /**
173 * check if string is a known status item.
174 *
175 * \param item buffer containing the text to check
176 *
177 * \return If \a item is a valid status item, the number of that status item is
178 * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
179 */
180 int stat_item_valid(const char *item)
181 {
182 int i;
183 if (!item || !*item) {
184 PARA_ERROR_LOG("%s\n", "no item");
185 return -E_UNKNOWN_STAT_ITEM;
186 }
187 FOR_EACH_STAT_ITEM(i)
188 if (!strcmp(status_item_list[i], item))
189 return i;
190 PARA_ERROR_LOG("invalid stat item: %s\n", item);
191 return -E_UNKNOWN_STAT_ITEM;
192 }
193
194 /**
195 * check if line starts with known status item.
196 *
197 * \param line buffer containing the line
198 *
199 * \return If the beginning of \a line matches any paraslash status item and is
200 * followed by a colon, the number of that status item is returned. Otherwise,
201 * this function returns \p -E_UNKNOWN_STAT_ITEM.
202 */
203 int stat_line_valid(const char *line)
204 {
205 int i;
206 size_t line_len;
207
208 if (!line || !*line)
209 return -E_UNKNOWN_STAT_ITEM;
210 line_len = strlen(line);
211 FOR_EACH_STAT_ITEM(i) {
212 const char *s = status_item_list[i];
213 size_t item_len = strlen(s);
214
215 if (line_len > item_len && line[item_len] == ':' &&
216 !strncmp(line, s, item_len))
217 return i;
218 }
219 return -E_UNKNOWN_STAT_ITEM;
220 }
221