Zvikomborero VIncent Zvikaramba | afe3e87 | 2016-07-24 20:53:15 -0400 | [diff] [blame] | 1 | /* Copyright (c) 2011, The Linux Foundation. All rights reserved. |
| 2 | * |
| 3 | * Redistribution and use in source and binary forms, with or without |
| 4 | * modification, are permitted provided that the following conditions are |
| 5 | * met: |
| 6 | * * Redistributions of source code must retain the above copyright |
| 7 | * notice, this list of conditions and the following disclaimer. |
| 8 | * * Redistributions in binary form must reproduce the above |
| 9 | * copyright notice, this list of conditions and the following |
| 10 | * disclaimer in the documentation and/or other materials provided |
| 11 | * with the distribution. |
| 12 | * * Neither the name of The Linux Foundation nor the names of its |
| 13 | * contributors may be used to endorse or promote products derived |
| 14 | * from this software without specific prior written permission. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED |
| 17 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 18 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT |
| 19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS |
| 20 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
| 23 | * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 24 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE |
| 25 | * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN |
| 26 | * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | */ |
| 28 | |
| 29 | #ifndef __MSG_Q_H__ |
| 30 | #define __MSG_Q_H__ |
| 31 | |
| 32 | #ifdef __cplusplus |
| 33 | extern "C" { |
| 34 | #endif /* __cplusplus */ |
| 35 | |
| 36 | #include <stdlib.h> |
| 37 | |
| 38 | /** Linked List Return Codes */ |
| 39 | typedef enum |
| 40 | { |
| 41 | eMSG_Q_SUCCESS = 0, |
| 42 | /**< Request was successful. */ |
| 43 | eMSG_Q_FAILURE_GENERAL = -1, |
| 44 | /**< Failed because of a general failure. */ |
| 45 | eMSG_Q_INVALID_PARAMETER = -2, |
| 46 | /**< Failed because the request contained invalid parameters. */ |
| 47 | eMSG_Q_INVALID_HANDLE = -3, |
| 48 | /**< Failed because an invalid handle was specified. */ |
| 49 | eMSG_Q_UNAVAILABLE_RESOURCE = -4, |
| 50 | /**< Failed because an there were not enough resources. */ |
| 51 | eMSG_Q_INSUFFICIENT_BUFFER = -5, |
| 52 | /**< Failed because an the supplied buffer was too small. */ |
| 53 | }msq_q_err_type; |
| 54 | |
| 55 | /*=========================================================================== |
| 56 | FUNCTION msg_q_init |
| 57 | |
| 58 | DESCRIPTION |
| 59 | Initializes internal structures for message queue. |
| 60 | |
| 61 | msg_q_data: pointer to an opaque Q handle to be returned; NULL if fails |
| 62 | |
| 63 | DEPENDENCIES |
| 64 | N/A |
| 65 | |
| 66 | RETURN VALUE |
| 67 | Look at error codes above. |
| 68 | |
| 69 | SIDE EFFECTS |
| 70 | N/A |
| 71 | |
| 72 | ===========================================================================*/ |
| 73 | msq_q_err_type msg_q_init(void** msg_q_data); |
| 74 | |
| 75 | /*=========================================================================== |
| 76 | FUNCTION msg_q_init2 |
| 77 | |
| 78 | DESCRIPTION |
| 79 | Initializes internal structures for message queue. |
| 80 | |
| 81 | DEPENDENCIES |
| 82 | N/A |
| 83 | |
| 84 | RETURN VALUE |
| 85 | opaque handle to the Q created; NULL if create fails |
| 86 | |
| 87 | SIDE EFFECTS |
| 88 | N/A |
| 89 | |
| 90 | ===========================================================================*/ |
| 91 | const void* msg_q_init2(); |
| 92 | |
| 93 | /*=========================================================================== |
| 94 | FUNCTION msg_q_destroy |
| 95 | |
| 96 | DESCRIPTION |
| 97 | Releases internal structures for message queue. |
| 98 | |
| 99 | msg_q_data: State of message queue to be released. |
| 100 | |
| 101 | DEPENDENCIES |
| 102 | N/A |
| 103 | |
| 104 | RETURN VALUE |
| 105 | Look at error codes above. |
| 106 | |
| 107 | SIDE EFFECTS |
| 108 | N/A |
| 109 | |
| 110 | ===========================================================================*/ |
| 111 | msq_q_err_type msg_q_destroy(void** msg_q_data); |
| 112 | |
| 113 | /*=========================================================================== |
| 114 | FUNCTION msg_q_snd |
| 115 | |
| 116 | DESCRIPTION |
| 117 | Sends data to the message queue. The passed in data pointer |
| 118 | is not modified or freed. Passed in msg_obj is expected to live throughout |
| 119 | the use of the msg_q (i.e. data is not allocated internally) |
| 120 | |
| 121 | msg_q_data: Message Queue to add the element to. |
| 122 | msgp: Pointer to data to add into message queue. |
| 123 | dealloc: Function used to deallocate memory for this element. Pass NULL |
| 124 | if you do not want data deallocated during a flush operation |
| 125 | |
| 126 | DEPENDENCIES |
| 127 | N/A |
| 128 | |
| 129 | RETURN VALUE |
| 130 | Look at error codes above. |
| 131 | |
| 132 | SIDE EFFECTS |
| 133 | N/A |
| 134 | |
| 135 | ===========================================================================*/ |
| 136 | msq_q_err_type msg_q_snd(void* msg_q_data, void* msg_obj, void (*dealloc)(void*)); |
| 137 | |
| 138 | /*=========================================================================== |
| 139 | FUNCTION msg_q_rcv |
| 140 | |
| 141 | DESCRIPTION |
| 142 | Retrieves data from the message queue. msg_obj is the oldest message received |
| 143 | and pointer is simply removed from message queue. |
| 144 | |
| 145 | msg_q_data: Message Queue to copy data from into msgp. |
| 146 | msg_obj: Pointer to space to copy msg_q contents to. |
| 147 | |
| 148 | DEPENDENCIES |
| 149 | N/A |
| 150 | |
| 151 | RETURN VALUE |
| 152 | Look at error codes above. |
| 153 | |
| 154 | SIDE EFFECTS |
| 155 | N/A |
| 156 | |
| 157 | ===========================================================================*/ |
| 158 | msq_q_err_type msg_q_rcv(void* msg_q_data, void** msg_obj); |
| 159 | |
| 160 | /*=========================================================================== |
| 161 | FUNCTION msg_q_flush |
| 162 | |
| 163 | DESCRIPTION |
| 164 | Function removes all elements from the message queue. |
| 165 | |
| 166 | msg_q_data: Message Queue to remove elements from. |
| 167 | |
| 168 | DEPENDENCIES |
| 169 | N/A |
| 170 | |
| 171 | RETURN VALUE |
| 172 | Look at error codes above. |
| 173 | |
| 174 | SIDE EFFECTS |
| 175 | N/A |
| 176 | |
| 177 | ===========================================================================*/ |
| 178 | msq_q_err_type msg_q_flush(void* msg_q_data); |
| 179 | |
| 180 | /*=========================================================================== |
| 181 | FUNCTION msg_q_unblock |
| 182 | |
| 183 | DESCRIPTION |
| 184 | This function will stop use of the message queue. All waiters will wake up |
| 185 | and likely receive nothing from the queue resulting in a negative return |
| 186 | value. The message queue can no longer be used until it is destroyed |
| 187 | and initialized again after calling this function. |
| 188 | |
| 189 | msg_q_data: Message queue to unblock. |
| 190 | |
| 191 | DEPENDENCIES |
| 192 | N/A |
| 193 | |
| 194 | RETURN VALUE |
| 195 | Look at error codes above. |
| 196 | |
| 197 | SIDE EFFECTS |
| 198 | N/A |
| 199 | |
| 200 | ===========================================================================*/ |
| 201 | msq_q_err_type msg_q_unblock(void* msg_q_data); |
| 202 | |
| 203 | #ifdef __cplusplus |
| 204 | } |
| 205 | #endif /* __cplusplus */ |
| 206 | |
| 207 | #endif /* __MSG_Q_H__ */ |