| 1 | /* |
| 2 | * lib/handlers.c default netlink message handlers |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation version 2.1 |
| 7 | * of the License. |
| 8 | * |
| 9 | * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch> |
| 10 | */ |
| 11 | |
| 12 | /** |
| 13 | * @ingroup core |
| 14 | * @defgroup cb Callbacks/Customization |
| 15 | * |
| 16 | * @details |
| 17 | * @par 1) Setting up a callback set |
| 18 | * @code |
| 19 | * // Allocate a callback set and initialize it to the verbose default set |
| 20 | * struct nl_cb *cb = nl_cb_alloc(NL_CB_VERBOSE); |
| 21 | * |
| 22 | * // Modify the set to call my_func() for all valid messages |
| 23 | * nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, my_func, NULL); |
| 24 | * |
| 25 | * // Set the error message handler to the verbose default implementation |
| 26 | * // and direct it to print all errors to the given file descriptor. |
| 27 | * FILE *file = fopen(...); |
| 28 | * nl_cb_err(cb, NL_CB_VERBOSE, NULL, file); |
| 29 | * @endcode |
| 30 | * @{ |
| 31 | */ |
| 32 | |
| 33 | #include <netlink-local.h> |
| 34 | #include <netlink/netlink.h> |
| 35 | #include <netlink/utils.h> |
| 36 | #include <netlink/msg.h> |
| 37 | #include <netlink/handlers.h> |
| 38 | |
| 39 | /** |
| 40 | * @name Callback Handle Management |
| 41 | * @{ |
| 42 | */ |
| 43 | |
| 44 | /** |
| 45 | * Allocate a new callback handle |
| 46 | * @arg kind callback kind to be used for initialization |
| 47 | * @return Newly allocated callback handle or NULL |
| 48 | */ |
| 49 | struct nl_cb *nl_cb_alloc(enum nl_cb_kind kind) |
| 50 | { |
| 51 | int i; |
| 52 | struct nl_cb *cb; |
| 53 | |
| 54 | if (kind < 0 || kind > NL_CB_KIND_MAX) |
| 55 | return NULL; |
| 56 | |
| 57 | cb = calloc(1, sizeof(*cb)); |
| 58 | if (!cb) |
| 59 | return NULL; |
| 60 | |
| 61 | cb->cb_refcnt = 1; |
| 62 | |
| 63 | for (i = 0; i <= NL_CB_TYPE_MAX; i++) |
| 64 | nl_cb_set(cb, i, kind, NULL, NULL); |
| 65 | |
| 66 | nl_cb_err(cb, kind, NULL, NULL); |
| 67 | |
| 68 | return cb; |
| 69 | } |
| 70 | |
| 71 | /** |
| 72 | * Clone an existing callback handle |
| 73 | * @arg orig original callback handle |
| 74 | * @return Newly allocated callback handle being a duplicate of |
| 75 | * orig or NULL |
| 76 | */ |
| 77 | struct nl_cb *nl_cb_clone(struct nl_cb *orig) |
| 78 | { |
| 79 | struct nl_cb *cb; |
| 80 | |
| 81 | cb = nl_cb_alloc(NL_CB_DEFAULT); |
| 82 | if (!cb) |
| 83 | return NULL; |
| 84 | |
| 85 | memcpy(cb, orig, sizeof(*orig)); |
| 86 | cb->cb_refcnt = 1; |
| 87 | |
| 88 | return cb; |
| 89 | } |
| 90 | |
| 91 | void nl_cb_put(struct nl_cb *cb) |
| 92 | { |
| 93 | if (!cb) |
| 94 | return; |
| 95 | |
| 96 | cb->cb_refcnt--; |
| 97 | |
| 98 | if (cb->cb_refcnt < 0) |
| 99 | BUG(); |
| 100 | |
| 101 | if (cb->cb_refcnt <= 0) |
| 102 | free(cb); |
| 103 | } |
| 104 | |
| 105 | /** @} */ |
| 106 | |
| 107 | /** |
| 108 | * @name Callback Setup |
| 109 | * @{ |
| 110 | */ |
| 111 | |
| 112 | /** |
| 113 | * Set up a callback |
| 114 | * @arg cb callback set |
| 115 | * @arg type callback to modify |
| 116 | * @arg kind kind of implementation |
| 117 | * @arg func callback function (NL_CB_CUSTOM) |
| 118 | * @arg arg argument passed to callback |
| 119 | * |
| 120 | * @return 0 on success or a negative error code |
| 121 | */ |
| 122 | int nl_cb_set(struct nl_cb *cb, enum nl_cb_type type, enum nl_cb_kind kind, |
| 123 | nl_recvmsg_msg_cb_t func, void *arg) |
| 124 | { |
| 125 | if (type < 0 || type > NL_CB_TYPE_MAX) |
| 126 | return -NLE_RANGE; |
| 127 | |
| 128 | if (kind < 0 || kind > NL_CB_KIND_MAX) |
| 129 | return -NLE_RANGE; |
| 130 | |
| 131 | if (kind == NL_CB_CUSTOM) { |
| 132 | cb->cb_set[type] = func; |
| 133 | cb->cb_args[type] = arg; |
| 134 | } |
| 135 | |
| 136 | return 0; |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * Set up an error callback |
| 141 | * @arg cb callback set |
| 142 | * @arg kind kind of callback |
| 143 | * @arg func callback function |
| 144 | * @arg arg argument to be passed to callback function |
| 145 | */ |
| 146 | int nl_cb_err(struct nl_cb *cb, enum nl_cb_kind kind, |
| 147 | nl_recvmsg_err_cb_t func, void *arg) |
| 148 | { |
| 149 | if (kind < 0 || kind > NL_CB_KIND_MAX) |
| 150 | return -NLE_RANGE; |
| 151 | |
| 152 | if (kind == NL_CB_CUSTOM) { |
| 153 | cb->cb_err = func; |
| 154 | cb->cb_err_arg = arg; |
| 155 | } |
| 156 | |
| 157 | return 0; |
| 158 | } |
| 159 | |
| 160 | /** @} */ |
| 161 | |
| 162 | /** @} */ |
| 163 | |
