command_util.sh: Don't replace newlines by spaces.
[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 [SI_LYRICS_ID] = "lyrics_id"
84 };
85
86 static void dump_stat_client_list(void)
87 {
88 struct stat_client *sc;
89
90 if (!initialized)
91 return;
92 list_for_each_entry(sc, &client_list, node)
93 PARA_INFO_LOG("stat client on fd %d\n", sc->fd);
94 }
95 /**
96 * add a status client to the list
97 *
98 * \param fd the file descriptor of the client
99 * \param mask bitfield of status items for this client
100 *
101 * Only those status items having the bit set in \a mask will be
102 * sent to the client.
103 *
104 * \return Positive value on success, or -E_TOO_MANY_CLIENTS if
105 * the number of connected clients exceeds #MAX_STAT_CLIENTS.
106 */
107 int stat_client_add(int fd, long unsigned mask)
108 {
109 struct stat_client *new_client;
110
111 if (num_clients >= MAX_STAT_CLIENTS) {
112 PARA_ERROR_LOG("maximal number of stat clients (%d) exceeded\n",
113 MAX_STAT_CLIENTS);
114 return -E_TOO_MANY_CLIENTS;
115 }
116 if (!initialized) {
117 INIT_LIST_HEAD(&client_list);
118 initialized = 1;
119 }
120 PARA_INFO_LOG("adding client on fd %d\n", fd);
121 new_client = para_malloc(sizeof(struct stat_client));
122 new_client->fd = fd;
123 new_client->item_mask = mask;
124 para_list_add(&new_client->node, &client_list);
125 dump_stat_client_list();
126 num_clients++;
127 return 1;
128 }
129 /**
130 * write a message to all connected status clients
131 *
132 * \param msg a \p NULL terminated buffer
133 * \param itemnum The number of the status item of \a msg
134 *
135 * On write errors, remove the status client from the client list and close its
136 * file descriptor.
137 */
138 void stat_client_write(const char *msg, int itemnum)
139 {
140 struct stat_client *sc, *tmp;
141 size_t len = strlen(msg);
142 struct timeval tv = {0 , 0};
143
144 if (!initialized || !len)
145 return;
146 list_for_each_entry_safe(sc, tmp, &client_list, node) {
147 int fd = sc->fd, ret;
148 fd_set wfds;
149
150 if (!((1 << itemnum) & sc->item_mask))
151 continue;
152 FD_ZERO(&wfds);
153 FD_SET(fd, &wfds);
154 // PARA_DEBUG_LOG("%s: p=%lx\n", __func__, (long)p);
155 ret = para_select(fd + 1, NULL, &wfds, &tv);
156 if (ret > 0) {
157 ret = write(fd, msg, len);
158 PARA_DEBUG_LOG("dumped %s to fd %d, ret = %d\n", msg, fd, ret);
159 if (ret == len )
160 continue;
161 }
162 /* write error or fd not ready for writing */
163 close(fd);
164 num_clients--;
165 PARA_INFO_LOG("deleting client on fd %d\n", fd);
166 list_del(&sc->node);
167 free(sc);
168 dump_stat_client_list();
169 }
170 PARA_DEBUG_LOG("%d client(s)\n", num_clients);
171 }
172
173 /**
174 * check if string is a known status item.
175 *
176 * \param item buffer containing the text to check
177 *
178 * \return If \a item is a valid status item, the number of that status item is
179 * returned. Otherwise, this function returns \p -E_UNKNOWN_STAT_ITEM.
180 */
181 int stat_item_valid(const char *item)
182 {
183 int i;
184 if (!item || !*item) {
185 PARA_ERROR_LOG("%s\n", "no item");
186 return -E_UNKNOWN_STAT_ITEM;
187 }
188 FOR_EACH_STAT_ITEM(i)
189 if (!strcmp(status_item_list[i], item))
190 return i;
191 PARA_ERROR_LOG("invalid stat item: %s\n", item);
192 return -E_UNKNOWN_STAT_ITEM;
193 }
194
195 /**
196 * check if line starts with known status item.
197 *
198 * \param line buffer containing the line
199 *
200 * \return If the beginning of \a line matches any paraslash status item and is
201 * followed by a colon, the number of that status item is returned. Otherwise,
202 * this function returns \p -E_UNKNOWN_STAT_ITEM.
203 */
204 int stat_line_valid(const char *line)
205 {
206 int i;
207 size_t line_len;
208
209 if (!line || !*line)
210 return -E_UNKNOWN_STAT_ITEM;
211 line_len = strlen(line);
212 FOR_EACH_STAT_ITEM(i) {
213 const char *s = status_item_list[i];
214 size_t item_len = strlen(s);
215
216 if (line_len > item_len && line[item_len] == ':' &&
217 !strncmp(line, s, item_len))
218 return i;
219 }
220 return -E_UNKNOWN_STAT_ITEM;
221 }
222