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.\" $FreeBSD$ 27.\" 28.Dd August 27, 2016 29.Dt CNV 9 30.Os 31.Sh NAME 32.Nm cnvlist_get, 33.Nm cnvlist_take, 34.Nm cnvlist_free, 35.Nd "API for managing name/value pairs by cookie." 36.Sh LIBRARY 37.Lb libnv 38.Sh SYNOPSIS 39.In sys/cnv.h 40.Ft bool 41.Fn cnvlist_get_bool "void *cookiep" 42.Ft uint64_t 43.Fn cnvlist_get_number "void *cookiep" 44.Ft "const char *" 45.Fn cnvlist_get_string "void *cookiep" 46.Ft "const nvlist_t *" 47.Fn cnvlist_get_nvlist "void *cookiep" 48.Ft "const void *" 49.Fn cnvlist_get_binary "void *cookiep" "size_t *sizep" 50.Ft "const bool *" 51.Fn cnvlist_get_bool_array "void *cookiep" "size_t *nitemsp" 52.Ft "const uint64_t *" 53.Fn cnvlist_get_number_array "void *cookiep" "size_t *nitemsp" 54.Ft "const char * const *" 55.Fn cnvlist_get_string_array "void *cookiep" "size_t *nitemsp" 56.Ft "const nvlist_t * const *" 57.Fn cnvlist_get_nvlist_array "void *cookiep" "size_t *nitemsp" 58.Ft int 59.Fn cnvlist_get_descriptor "void *cookiep" 60.Ft "const int *" 61.Fn cnvlist_get_descriptor_array "void *cookiep" "size_t *nitemsp" 62.\" 63.Ft bool 64.Fn cnvlist_take_bool "void *cookiep" 65.Ft uint64_t 66.Fn cnvlist_take_number "void *cookiep" 67.Ft "const char *" 68.Fn cnvlist_take_string "void *cookiep" 69.Ft "const nvlist_t *" 70.Fn cnvlist_take_nvlist "void *cookiep" 71.Ft "const void *" 72.Fn cnvlist_take_binary "void *cookiep" "size_t *sizep" 73.Ft "const bool *" 74.Fn cnvlist_take_bool_array "void *cookiep" "size_t *nitemsp" 75.Ft "const uint64_t *" 76.Fn cnvlist_take_number_array "void *cookiep" "size_t *nitemsp" 77.Ft "const char * const *" 78.Fn cnvlist_take_string_array "void *cookiep" "size_t *nitemsp" 79.Ft "const nvlist_t * const *" 80.Fn cnvlist_take_nvlist_array "void *cookiep" "size_t *nitemsp" 81.Ft int 82.Fn cnvlist_take_descriptor "void *cookiep" 83.Ft "const int *" 84.Fn cnvlist_take_descriptor_array "void *cookiep" "size_t *nitemsp" 85.\" 86.Ft void 87.Fn cnvlist_free_null "nvlist_t *nvl" "void *cookiep" 88.Ft void 89.Fn cnvlist_free_bool "nvlist_t *nvl" "void *cookiep" 90.Ft void 91.Fn cnvlist_free_number "nvlist_t *nvl" "void *cookiep" 92.Ft void 93.Fn cnvlist_free_string "nvlist_t *nvl" "void *cookiep" 94.Ft void 95.Fn cnvlist_free_nvlist "nvlist_t *nvl" "void *cookiep" 96.Ft void 97.Fn cnvlist_free_descriptor "nvlist_t *nvl" "void *cookiep" 98.Ft void 99.Fn cnvlist_free_binary "nvlist_t *nvl" "void *cookiep" 100.Ft void 101.Fn cnvlist_free_bool_array "nvlist_t *nvl" "void *cookiep" 102.Ft void 103.Fn cnvlist_free_number_array "nvlist_t *nvl" "void *cookiep" 104.Ft void 105.Fn cnvlist_free_string_array "nvlist_t *nvl" "void *cookiep" 106.Ft void 107.Fn cnvlist_free_nvlist_array "nvlist_t *nvl" "void *cookiep" 108.Ft void 109.Fn cnvlist_free_descriptor_array "nvlist_t *nvl" "void *cookiep" 110.Sh DESCRIPTION 111The 112.Nm libnv 113library permits easy management of name/value pairs and can send and receive 114them over sockets. 115For more information, also see 116.Xr nv 9 . 117.Pp 118The concept of cookies is explained in 119.Fn nvlist_next , 120.Fn nvlist_get_parent , 121and 122.Fn nvlist_get_pararr 123from 124.Xr nv 9 . 125.Pp 126The 127.Nm cnvlist_get 128family of functions obtains the value associated with the given cookie. 129Returned strings, nvlists, descriptors, binaries, or arrays must not be modified 130by the user, since they still belong to the nvlist. 131The nvlist must not be in an error state. 132.Pp 133The 134.Nm cnvlist_take 135family of functions returns the value associated with the given cookie and 136removes the element from the nvlist. 137When the value is a string, binary, or array value, the caller is responsible 138for freeing the returned memory with 139.Fn free 3 . 140When the value is an nvlist, the caller is responsible for destroying the 141returned nvlist with 142.Fn nvlist_destroy . 143When the value is a descriptor, the caller is responsible for closing the 144returned descriptor with the 145.Fn close 2 . 146.Pp 147The 148.Nm cnvlist_free 149family of functions removes an element of the supplied cookie and frees all 150resources. 151If an element of the given cookie has the wrong type or does not exist, the 152program 153is aborted. 154.Sh EXAMPLE 155The following example demonstrates how to deal with cnvlist API. 156.Bd -literal 157int type; 158void *cookie, *scookie, *bcookie; 159nvlist_t *nvl; 160char *name; 161 162nvl = nvlist_create(0); 163nvlist_add_bool(nvl, "test", 1 == 2); 164nvlist_add_string(nvl, "test2", "cnvlist"); 165cookie = NULL; 166 167while (nvlist_next(nvl, &type, &cookie) != NULL) { 168 switch (type) { 169 case NV_TYPE_BOOL: 170 printf("test: %d\\n", cnvlist_get_bool(cookie)); 171 bcookie = cookie; 172 break; 173 case NV_TYPE_STRING: 174 printf("test2: %s\\n", cnvlist_get_string(cookie)); 175 scookie = cookie; 176 break; 177 } 178} 179 180name = cnvlist_take_string(nvl, scookie); 181cnvlist_free_bool(nvl, bcookie); 182 183printf("test2: %s\\n", name); 184free(name); 185 186printf("nvlist_empty = %d\\n", nvlist_empty(nvl)); 187nvlist_destroy(nvl); 188 189return (0); 190.Ed 191.Sh SEE ALSO 192.Xr close 2 , 193.Xr free 3 , 194.Xr nv 9 195.Sh AUTHORS 196The 197.Nm cnv 198API was created during the Google Summer Of Code 2016 by 199.An Adam Starak . 200