1 #ifndef footxtlisthfoo
2 #define footxtlisthfoo
3 
4 /***
5   This file is part of avahi.
6 
7   avahi is free software; you can redistribute it and/or modify it
8   under the terms of the GNU Lesser General Public License as
9   published by the Free Software Foundation; either version 2.1 of the
10   License, or (at your option) any later version.
11 
12   avahi is distributed in the hope that it will be useful, but WITHOUT
13   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
15   Public License for more details.
16 
17   You should have received a copy of the GNU Lesser General Public
18   License along with avahi; if not, write to the Free Software
19   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
20   USA.
21 ***/
22 
23 /** \file strlst.h Implementation of a data type to store lists of strings */
24 
25 #include <sys/types.h>
26 #include <inttypes.h>
27 #include <stdarg.h>
28 
29 #include <avahi-common/cdecl.h>
30 #include <avahi-common/gccmacro.h>
31 
32 AVAHI_C_DECL_BEGIN
33 
34 /** Linked list of strings that can contain any number of binary
35  * characters, including NUL bytes. An empty list is created by
36  * assigning a NULL to a pointer to AvahiStringList. The string list
37  * is stored in reverse order, so that appending to the string list is
38  * effectively a prepending to the linked list.  This object is used
39  * primarily for storing DNS TXT record data. */
40 typedef struct AvahiStringList {
41     struct AvahiStringList *next; /**< Pointer to the next linked list element */
42     size_t size;  /**< Size of text[] */
43     uint8_t text[1]; /**< Character data */
44 } AvahiStringList;
45 
46 /** @{ \name Construction and destruction */
47 
48 /** Create a new string list by taking a variable list of NUL
49  * terminated strings. The strings are copied using g_strdup(). The
50  * argument list must be terminated by a NULL pointer. */
51 AvahiStringList *avahi_string_list_new(const char *txt, ...) AVAHI_GCC_SENTINEL;
52 
53 /** \cond fulldocs */
54 /** Same as avahi_string_list_new() but pass a va_list structure */
55 AvahiStringList *avahi_string_list_new_va(va_list va);
56 /** \endcond */
57 
58 /** Create a new string list from a string array. The strings are
59  * copied using g_strdup(). length should contain the length of the
60  * array, or -1 if the array is NULL terminated*/
61 AvahiStringList *avahi_string_list_new_from_array(const char **array, int length);
62 
63 /** Free a string list */
64 void avahi_string_list_free(AvahiStringList *l);
65 
66 /** @} */
67 
68 /** @{ \name Adding strings */
69 
70 /** Append a NUL terminated string to the specified string list. The
71  * passed string is copied using g_strdup(). Returns the new list
72  * start. */
73 AvahiStringList *avahi_string_list_add(AvahiStringList *l, const char *text);
74 
75 /** Append a new NUL terminated formatted string to the specified string list */
76 AvahiStringList *avahi_string_list_add_printf(AvahiStringList *l, const char *format, ...) AVAHI_GCC_PRINTF_ATTR23;
77 
78 /** \cond fulldocs */
79 /** Append a new NUL terminated formatted string to the specified string list */
80 AvahiStringList *avahi_string_list_add_vprintf(AvahiStringList *l, const char *format, va_list va);
81 /** \endcond */
82 
83 /** Append an arbitrary length byte string to the list. Returns the
84  * new list start. */
85 AvahiStringList *avahi_string_list_add_arbitrary(AvahiStringList *l, const uint8_t *text, size_t size);
86 
87 /** Append a new entry to the string list. The string is not filled
88 with data. The caller should fill in string data afterwards by writing
89 it to l->text, where l is the pointer returned by this function. This
90 function exists solely to optimize a few operations where otherwise
91 superfluous string copying would be necessary. */
92 AvahiStringList*avahi_string_list_add_anonymous(AvahiStringList *l, size_t size);
93 
94 /** Same as avahi_string_list_add(), but takes a variable number of
95  * NUL terminated strings. The argument list must be terminated by a
96  * NULL pointer. Returns the new list start. */
97 AvahiStringList *avahi_string_list_add_many(AvahiStringList *r, ...) AVAHI_GCC_SENTINEL;
98 
99 /** \cond fulldocs */
100 /** Same as avahi_string_list_add_many(), but use a va_list
101  * structure. Returns the new list start. */
102 AvahiStringList *avahi_string_list_add_many_va(AvahiStringList *r, va_list va);
103 /** \endcond */
104 
105 /** @} */
106 
107 /** @{ \name String list operations */
108 
109 /** Convert the string list object to a single character string,
110  * seperated by spaces and enclosed in "". avahi_free() the result! This
111  * function doesn't work well with strings that contain NUL bytes. */
112 char* avahi_string_list_to_string(AvahiStringList *l);
113 
114 /** \cond fulldocs */
115 /** Serialize the string list object in a way that is compatible with
116  * the storing of DNS TXT records. Strings longer than 255 bytes are truncated. */
117 size_t avahi_string_list_serialize(AvahiStringList *l, void * data, size_t size);
118 
119 /** Inverse of avahi_string_list_serialize() */
120 int avahi_string_list_parse(const void *data, size_t size, AvahiStringList **ret);
121 /** \endcond */
122 
123 /** Compare to string lists */
124 int avahi_string_list_equal(const AvahiStringList *a, const AvahiStringList *b);
125 
126 /** Copy a string list */
127 AvahiStringList *avahi_string_list_copy(const AvahiStringList *l);
128 
129 /** Reverse the string list. */
130 AvahiStringList* avahi_string_list_reverse(AvahiStringList *l);
131 
132 /** Return the number of elements in the string list */
133 unsigned avahi_string_list_length(const AvahiStringList *l);
134 
135 /** @} */
136 
137 /** @{ \name Accessing items */
138 
139 /** Returns the next item in the string list */
140 AvahiStringList *avahi_string_list_get_next(AvahiStringList *l);
141 
142 /** Returns the text for the current item */
143 uint8_t *avahi_string_list_get_text(AvahiStringList *l);
144 
145 /** Returns the size of the current text */
146 size_t avahi_string_list_get_size(AvahiStringList *l);
147 
148 /** @} */
149 
150 /** @{ \name DNS-SD TXT pair handling */
151 
152 /** Find the string list entry for the given DNS-SD TXT key */
153 AvahiStringList *avahi_string_list_find(AvahiStringList *l, const char *key);
154 
155 /** Return the DNS-SD TXT key and value for the specified string list
156  * item. If size is not NULL it will be filled with the length of
157  * value. (for strings containing NUL bytes). If the entry doesn't
158  * contain a value *value will be set to NULL. You need to
159  * avahi_free() the strings returned in *key and *value. */
160 int avahi_string_list_get_pair(AvahiStringList *l, char **key, char **value, size_t *size);
161 
162 /** Add a new DNS-SD TXT key value pair to the string list. value may
163  * be NULL in case you want to specify a key without a value */
164 AvahiStringList *avahi_string_list_add_pair(AvahiStringList *l, const char *key, const char *value);
165 
166 /** Same as avahi_string_list_add_pair() but allow strings containing NUL bytes in *value. */
167 AvahiStringList *avahi_string_list_add_pair_arbitrary(AvahiStringList *l, const char *key, const uint8_t *value, size_t size);
168 
169 /** @} */
170 
171 /** \cond fulldocs */
172 /** Try to find a magic service cookie in the specified DNS-SD string
173  * list. Or return AVAHI_SERVICE_COOKIE_INVALID if none is found. */
174 uint32_t avahi_string_list_get_service_cookie(AvahiStringList *l);
175 /** \endcond */
176 
177 AVAHI_C_DECL_END
178 
179 #endif
180 
181