1.\" 2.\" Copyright (c) 2016 Adam Starak <starak.adam@gmail.com> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.Dd June 18, 2018 27.Dt CNV 9 28.Os 29.Sh NAME 30.Nm cnvlist_get , 31.Nm cnvlist_take , 32.Nm cnvlist_free 33.Nd "API for managing name/value pairs by cookie." 34.Sh LIBRARY 35.Lb libnv 36.Sh SYNOPSIS 37.In sys/cnv.h 38.Ft const char * 39.Fn cnvlist_name "const void *cookie" 40.Ft int 41.Fn cnvlist_type "const void *cookie" 42.\" 43.Ft bool 44.Fn cnvlist_get_bool "const void *cookie" 45.Ft uint64_t 46.Fn cnvlist_get_number "const void *cookie" 47.Ft "const char *" 48.Fn cnvlist_get_string "const void *cookie" 49.Ft "const nvlist_t *" 50.Fn cnvlist_get_nvlist "const void *cookie" 51.Ft "const void *" 52.Fn cnvlist_get_binary "const void *cookie" "size_t *sizep" 53.Ft "const bool *" 54.Fn cnvlist_get_bool_array "const void *cookie" "size_t *nitemsp" 55.Ft "const uint64_t *" 56.Fn cnvlist_get_number_array "const void *cookie" "size_t *nitemsp" 57.Ft "const char * const *" 58.Fn cnvlist_get_string_array "const void *cookie" "size_t *nitemsp" 59.Ft "const nvlist_t * const *" 60.Fn cnvlist_get_nvlist_array "const void *cookie" "size_t *nitemsp" 61.Ft int 62.Fn cnvlist_get_descriptor "const void *cookie" 63.Ft "const int *" 64.Fn cnvlist_get_descriptor_array "const void *cookie" "size_t *nitemsp" 65.\" 66.Ft bool 67.Fn cnvlist_take_bool "void *cookie" 68.Ft uint64_t 69.Fn cnvlist_take_number "void *cookie" 70.Ft "const char *" 71.Fn cnvlist_take_string "void *cookie" 72.Ft "const nvlist_t *" 73.Fn cnvlist_take_nvlist "void *cookie" 74.Ft "const void *" 75.Fn cnvlist_take_binary "void *cookie" "size_t *sizep" 76.Ft "const bool *" 77.Fn cnvlist_take_bool_array "void *cookie" "size_t *nitemsp" 78.Ft "const uint64_t *" 79.Fn cnvlist_take_number_array "void *cookie" "size_t *nitemsp" 80.Ft "const char * const *" 81.Fn cnvlist_take_string_array "void *cookie" "size_t *nitemsp" 82.Ft "const nvlist_t * const *" 83.Fn cnvlist_take_nvlist_array "void *cookie" "size_t *nitemsp" 84.Ft int 85.Fn cnvlist_take_descriptor "void *cookie" 86.Ft "const int *" 87.Fn cnvlist_take_descriptor_array "void *cookie" "size_t *nitemsp" 88.\" 89.Ft void 90.Fn cnvlist_free_null "void *cookie" 91.Ft void 92.Fn cnvlist_free_bool "void *cookie" 93.Ft void 94.Fn cnvlist_free_number "void *cookie" 95.Ft void 96.Fn cnvlist_free_string "void *cookie" 97.Ft void 98.Fn cnvlist_free_nvlist "void *cookie" 99.Ft void 100.Fn cnvlist_free_descriptor "void *cookie" 101.Ft void 102.Fn cnvlist_free_binary "void *cookie" 103.Ft void 104.Fn cnvlist_free_bool_array "void *cookie" 105.Ft void 106.Fn cnvlist_free_number_array "void *cookie" 107.Ft void 108.Fn cnvlist_free_string_array "void *cookie" 109.Ft void 110.Fn cnvlist_free_nvlist_array "void *cookie" 111.Ft void 112.Fn cnvlist_free_descriptor_array "void *cookie" 113.Sh DESCRIPTION 114The 115.Nm libnv 116library permits easy management of name/value pairs and can send and receive 117them over sockets. 118For more information, also see 119.Xr nv 9 . 120.Pp 121The concept of cookies is explained in 122.Fn nvlist_next , 123.Fn nvlist_get_parent , 124and 125.Fn nvlist_get_pararr 126from 127.Xr nv 9 . 128.Pp 129The 130.Fn cnvlist_name 131function returns the name of an element associated with the given cookie. 132.Pp 133The 134.Fn cnvlist_type 135function returns the type of an element associated with the given cookie. 136Types which can be returned are described in 137.Xr nv 9 . 138.Pp 139The 140.Nm cnvlist_get 141family of functions obtains the value associated with the given cookie. 142Returned strings, nvlists, descriptors, binaries, or arrays must not be modified 143by the user, since they still belong to the nvlist. 144The nvlist must not be in an error state. 145.Pp 146The 147.Nm cnvlist_take 148family of functions returns the value associated with the given cookie and 149removes the element from the nvlist. 150When the value is a string, binary, or array value, the caller is responsible 151for freeing the returned memory with 152.Fn free 3 . 153When the value is an nvlist, the caller is responsible for destroying the 154returned nvlist with 155.Fn nvlist_destroy . 156When the value is a descriptor, the caller is responsible for closing the 157returned descriptor with the 158.Fn close 2 . 159.Pp 160The 161.Nm cnvlist_free 162family of functions removes an element of the supplied cookie and frees all 163resources. 164If an element of the given cookie has the wrong type or does not exist, the 165program 166is aborted. 167.Sh EXAMPLES 168The following example demonstrates how to deal with cnvlist API. 169.Bd -literal 170int type; 171void *cookie, *scookie, *bcookie; 172nvlist_t *nvl; 173char *name; 174 175nvl = nvlist_create(0); 176nvlist_add_bool(nvl, "test", 1 == 2); 177nvlist_add_string(nvl, "test2", "cnvlist"); 178cookie = NULL; 179 180while (nvlist_next(nvl, &type, &cookie) != NULL) { 181 switch (type) { 182 case NV_TYPE_BOOL: 183 printf("test: %d\\n", cnvlist_get_bool(cookie)); 184 bcookie = cookie; 185 break; 186 case NV_TYPE_STRING: 187 printf("test2: %s\\n", cnvlist_get_string(cookie)); 188 scookie = cookie; 189 break; 190 } 191} 192 193name = cnvlist_take_string(scookie); 194cnvlist_free_bool(bcookie); 195 196printf("test2: %s\\n", name); 197free(name); 198 199printf("nvlist_empty = %d\\n", nvlist_empty(nvl)); 200nvlist_destroy(nvl); 201 202return (0); 203.Ed 204.Sh SEE ALSO 205.Xr close 2 , 206.Xr free 3 , 207.Xr nv 9 208.Sh AUTHORS 209The 210.Nm cnv 211API was created during the Google Summer Of Code 2016 by 212.An Adam Starak . 213