WizziLab / WizziCom

WizziLab's serial protocol library

Dependents:   modem_ref_helper_for_v5_3_217 modem_ref_helper

kal_buf_circ.cpp@10:c87566aded6e, 2021-01-25 (annotated)

Committer:
Jeej
Date:
Mon Jan 25 11:23:32 2021 +0000
Revision:
10:c87566aded6e
Parent:
9:0140247bab90 
Added space function in buffer

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jeej 9:0140247bab90 1 /// @copyright
Jeej 9:0140247bab90 2 /// ========================================================================={{{
Jeej 9:0140247bab90 3 /// Copyright (c) 2019 WizziLab /
Jeej 9:0140247bab90 4 /// All rights reserved /
Jeej 9:0140247bab90 5 /// /
Jeej 9:0140247bab90 6 /// IMPORTANT: This Software may not be modified, copied or distributed unless /
Jeej 9:0140247bab90 7 /// embedded on a WizziLab product. Other than for the foregoing purpose, this /
Jeej 9:0140247bab90 8 /// Software and/or its documentation may not be used, reproduced, copied, /
Jeej 9:0140247bab90 9 /// prepared derivative works of, modified, performed, distributed, displayed /
Jeej 9:0140247bab90 10 /// or sold for any purpose. For the sole purpose of embedding this Software /
Jeej 9:0140247bab90 11 /// on a WizziLab product, copy, modification and distribution of this /
Jeej 9:0140247bab90 12 /// Software is granted provided that the following conditions are respected: /
Jeej 9:0140247bab90 13 /// /
Jeej 9:0140247bab90 14 /// * Redistributions of source code must retain the above copyright notice, /
Jeej 9:0140247bab90 15 /// this list of conditions and the following disclaimer /
Jeej 9:0140247bab90 16 /// /
Jeej 9:0140247bab90 17 /// * Redistributions in binary form must reproduce the above copyright /
Jeej 9:0140247bab90 18 /// notice, this list of conditions and the following disclaimer in the /
Jeej 9:0140247bab90 19 /// documentation and/or other materials provided with the distribution. /
Jeej 9:0140247bab90 20 /// /
Jeej 9:0140247bab90 21 /// * The name of WizziLab can not be used to endorse or promote products /
Jeej 9:0140247bab90 22 /// derived from this software without specific prior written permission. /
Jeej 9:0140247bab90 23 /// /
Jeej 9:0140247bab90 24 /// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS /
Jeej 9:0140247bab90 25 /// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED /
Jeej 9:0140247bab90 26 /// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR /
Jeej 9:0140247bab90 27 /// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR /
Jeej 9:0140247bab90 28 /// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, /
Jeej 9:0140247bab90 29 /// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, /
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Jeej 9:0140247bab90 32 /// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING /
Jeej 9:0140247bab90 33 /// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS /
Jeej 9:0140247bab90 34 /// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. /
Jeej 9:0140247bab90 35 /// WIZZILAB HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, /
Jeej 9:0140247bab90 36 /// ENHANCEMENTS OR MODIFICATIONS. /
Jeej 9:0140247bab90 37 /// /
Jeej 9:0140247bab90 38 /// Should you have any questions regarding your right to use this Software, /
Jeej 9:0140247bab90 39 /// contact WizziLab at www.wizzilab.com. /
Jeej 9:0140247bab90 40 /// /
Jeej 9:0140247bab90 41 /// =========================================================================}}}
Jeej 9:0140247bab90 42 /// @endcopyright
Jeej 9:0140247bab90 43
Jeej 9:0140247bab90 44 /// XXX: New code for reference. Still to be tested.
Jeej 9:0140247bab90 45
Jeej 9:0140247bab90 46 #include "kal_buf_circ.h"
Jeej 9:0140247bab90 47
Jeej 9:0140247bab90 48 #if defined(KAL_MALLOC) && defined(KAL_FREE)
Jeej 9:0140247bab90 49 #ifndef CIRCULAR_BUFFER_MALLOC
Jeej 9:0140247bab90 50 #define CIRCULAR_BUFFER_MALLOC(_s) KAL_MALLOC(_s)
Jeej 9:0140247bab90 51 #endif
Jeej 9:0140247bab90 52 #ifndef CIRCULAR_BUFFER_FREE
Jeej 9:0140247bab90 53 #define CIRCULAR_BUFFER_FREE(_p) KAL_FREE(_p)
Jeej 9:0140247bab90 54 #endif
Jeej 10:c87566aded6e 55 #define CIRCULAR_BUFFER_DYNAMIC
Jeej 9:0140247bab90 56 #endif
Jeej 9:0140247bab90 57
Jeej 9:0140247bab90 58 static __inline uint32_t kal_buf_circ_next_head(kal_buf_circ_static_handle_t* h, uint32_t nb_elements)
Jeej 9:0140247bab90 59 {
Jeej 9:0140247bab90 60 uint32_t next = h->head + (nb_elements * h->element_size);
Jeej 9:0140247bab90 61 return (next >= h->max_length)? next - h->max_length : next;
Jeej 9:0140247bab90 62 }
Jeej 9:0140247bab90 63
Jeej 9:0140247bab90 64 static __inline uint32_t kal_buf_circ_next_tail(kal_buf_circ_static_handle_t* h, uint32_t nb_elements)
Jeej 9:0140247bab90 65 {
Jeej 9:0140247bab90 66 uint32_t next = h->tail + (nb_elements * h->element_size);
Jeej 9:0140247bab90 67 return (next >= h->max_length)? next - h->max_length : next;
Jeej 9:0140247bab90 68 }
Jeej 9:0140247bab90 69
Jeej 10:c87566aded6e 70 #ifdef CIRCULAR_BUFFER_DYNAMIC
Jeej 9:0140247bab90 71 kal_buf_circ_handle_t kal_buf_circ_create(uint32_t nb_elements, uint32_t element_size)
Jeej 9:0140247bab90 72 {
Jeej 9:0140247bab90 73 // Malloc the h and the buffer
Jeej 9:0140247bab90 74 kal_buf_circ_static_handle_t* h = CIRCULAR_BUFFER_MALLOC(sizeof(kal_buf_circ_static_handle_t));
Jeej 9:0140247bab90 75
Jeej 9:0140247bab90 76 h->buffer = (uint8_t*)CIRCULAR_BUFFER_MALLOC((nb_elements + 1) * element_size);
Jeej 9:0140247bab90 77 h->head = 0;
Jeej 9:0140247bab90 78 h->tail = 0;
Jeej 9:0140247bab90 79 h->element_size = element_size;
Jeej 9:0140247bab90 80 h->max_length = (nb_elements + 1) * element_size;
Jeej 9:0140247bab90 81 h->is_static = false;
Jeej 9:0140247bab90 82
Jeej 9:0140247bab90 83 return (kal_buf_circ_handle_t)h;
Jeej 9:0140247bab90 84 }
Jeej 9:0140247bab90 85 #endif
Jeej 9:0140247bab90 86
Jeej 9:0140247bab90 87 int kal_buf_circ_create_static(kal_buf_circ_static_handle_t* static_handle, uint8_t* buffer, uint32_t nb_elements, uint32_t element_size)
Jeej 9:0140247bab90 88 {
Jeej 9:0140247bab90 89 // h and buffer are passed as parameters.
Jeej 9:0140247bab90 90 kal_buf_circ_static_handle_t* h = static_handle;
Jeej 9:0140247bab90 91
Jeej 9:0140247bab90 92 h->buffer = buffer;
Jeej 9:0140247bab90 93 h->head = 0;
Jeej 9:0140247bab90 94 h->tail = 0;
Jeej 9:0140247bab90 95 h->element_size = element_size;
Jeej 9:0140247bab90 96 h->max_length = (nb_elements + 1) * element_size;
Jeej 9:0140247bab90 97 h->is_static = true;
Jeej 9:0140247bab90 98
Jeej 9:0140247bab90 99 return 0;
Jeej 9:0140247bab90 100 }
Jeej 9:0140247bab90 101
Jeej 9:0140247bab90 102 int kal_buf_circ_delete(kal_buf_circ_handle_t handle)
Jeej 9:0140247bab90 103 {
Jeej 9:0140247bab90 104 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 105
Jeej 9:0140247bab90 106 if (h->is_static)
Jeej 9:0140247bab90 107 {
Jeej 9:0140247bab90 108 // Set h to 0
Jeej 9:0140247bab90 109 memset(h->buffer, 0, h->max_length);
Jeej 9:0140247bab90 110 memset(h, 0, sizeof(kal_buf_circ_static_handle_t));
Jeej 9:0140247bab90 111 }
Jeej 10:c87566aded6e 112 #ifdef CIRCULAR_BUFFER_DYNAMIC
Jeej 9:0140247bab90 113 else
Jeej 9:0140247bab90 114 {
Jeej 9:0140247bab90 115 CIRCULAR_BUFFER_FREE(h->buffer);
Jeej 9:0140247bab90 116 CIRCULAR_BUFFER_FREE(h);
Jeej 9:0140247bab90 117 }
Jeej 9:0140247bab90 118 #endif
Jeej 9:0140247bab90 119
Jeej 9:0140247bab90 120 return 0;
Jeej 9:0140247bab90 121 }
Jeej 9:0140247bab90 122
Jeej 9:0140247bab90 123 int kal_buf_circ_reset(kal_buf_circ_handle_t handle)
Jeej 9:0140247bab90 124 {
Jeej 9:0140247bab90 125 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 126
Jeej 9:0140247bab90 127 h->head = 0;
Jeej 9:0140247bab90 128 h->tail = 0;
Jeej 9:0140247bab90 129 memset(h->buffer, 0, h->max_length);
Jeej 9:0140247bab90 130
Jeej 9:0140247bab90 131 return 0;
Jeej 9:0140247bab90 132 }
Jeej 9:0140247bab90 133
Jeej 10:c87566aded6e 134 int kal_buf_circ_full(kal_buf_circ_handle_t handle)
Jeej 9:0140247bab90 135 {
Jeej 9:0140247bab90 136 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 137
Jeej 9:0140247bab90 138 // if the next head is the tail, circular buffer is full
Jeej 9:0140247bab90 139 return (kal_buf_circ_next_head(h, 1) == h->tail)? true : false;
Jeej 9:0140247bab90 140 }
Jeej 9:0140247bab90 141
Jeej 10:c87566aded6e 142 int kal_buf_circ_empty(kal_buf_circ_handle_t handle)
Jeej 9:0140247bab90 143 {
Jeej 9:0140247bab90 144 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 145
Jeej 9:0140247bab90 146 // if the head isn't ahead of the tail, we don't have any elements
Jeej 9:0140247bab90 147 return (h->head == h->tail)? true : false;
Jeej 9:0140247bab90 148 }
Jeej 9:0140247bab90 149
Jeej 9:0140247bab90 150 uint32_t kal_buf_circ_size(kal_buf_circ_handle_t handle)
Jeej 9:0140247bab90 151 {
Jeej 9:0140247bab90 152 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 153
Jeej 9:0140247bab90 154 // head is ahead of tail
Jeej 9:0140247bab90 155 if (h->head >= h->tail)
Jeej 9:0140247bab90 156 {
Jeej 9:0140247bab90 157 // return the difference
Jeej 9:0140247bab90 158 return (h->head - h->tail) / h->element_size;
Jeej 9:0140247bab90 159 }
Jeej 9:0140247bab90 160 else
Jeej 9:0140247bab90 161 {
Jeej 9:0140247bab90 162 // else add max_length
Jeej 9:0140247bab90 163 return (h->max_length + h->head - h->tail) / h->element_size;
Jeej 9:0140247bab90 164 }
Jeej 9:0140247bab90 165 }
Jeej 9:0140247bab90 166
Jeej 10:c87566aded6e 167 uint32_t kal_buf_circ_space(kal_buf_circ_handle_t handle)
Jeej 10:c87566aded6e 168 {
Jeej 10:c87566aded6e 169 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 10:c87566aded6e 170
Jeej 10:c87566aded6e 171 return ((h->max_length / h->element_size) - 1) - kal_buf_circ_size(handle);
Jeej 10:c87566aded6e 172 }
Jeej 10:c87566aded6e 173
Jeej 9:0140247bab90 174 int kal_buf_circ_push(kal_buf_circ_handle_t handle, uint8_t* p)
Jeej 9:0140247bab90 175 {
Jeej 9:0140247bab90 176 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 177
Jeej 9:0140247bab90 178 // check if circular buffer is full
Jeej 9:0140247bab90 179 if (kal_buf_circ_full(handle))
Jeej 9:0140247bab90 180 {
Jeej 9:0140247bab90 181 return -1; // and return with an error.
Jeej 9:0140247bab90 182 }
Jeej 9:0140247bab90 183
Jeej 9:0140247bab90 184 // next is where head will point to after this write.
Jeej 9:0140247bab90 185 uint32_t next = kal_buf_circ_next_head(h, 1);
Jeej 9:0140247bab90 186
Jeej 9:0140247bab90 187 // Load data and then move
Jeej 9:0140247bab90 188 memcpy(&(h->buffer[h->head]), p, h->element_size);
Jeej 9:0140247bab90 189
Jeej 9:0140247bab90 190 // head to next data offset.
Jeej 9:0140247bab90 191 h->head = next;
Jeej 9:0140247bab90 192
Jeej 9:0140247bab90 193 // return success to indicate successful push.
Jeej 9:0140247bab90 194 return 0;
Jeej 9:0140247bab90 195 }
Jeej 9:0140247bab90 196
Jeej 9:0140247bab90 197 int kal_buf_circ_pop(kal_buf_circ_handle_t handle, uint8_t* p)
Jeej 9:0140247bab90 198 {
Jeej 9:0140247bab90 199 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 200
Jeej 9:0140247bab90 201 // check if circular buffer is empty
Jeej 9:0140247bab90 202 if (kal_buf_circ_empty(handle))
Jeej 9:0140247bab90 203 {
Jeej 9:0140247bab90 204 return -1; // and return with an error
Jeej 9:0140247bab90 205 }
Jeej 9:0140247bab90 206
Jeej 9:0140247bab90 207 // next is where tail will point to after this read.
Jeej 9:0140247bab90 208 uint32_t next = kal_buf_circ_next_tail(h, 1);
Jeej 9:0140247bab90 209
Jeej 9:0140247bab90 210 if (p)
Jeej 9:0140247bab90 211 {
Jeej 9:0140247bab90 212 // Read data and then move
Jeej 9:0140247bab90 213 memcpy(p, &(h->buffer[h->tail]), h->element_size);
Jeej 9:0140247bab90 214 }
Jeej 9:0140247bab90 215
Jeej 9:0140247bab90 216 // tail to next data offset.
Jeej 9:0140247bab90 217 h->tail = next;
Jeej 9:0140247bab90 218
Jeej 9:0140247bab90 219 // return success to indicate successful pop.
Jeej 9:0140247bab90 220 return 0;
Jeej 9:0140247bab90 221 }
Jeej 9:0140247bab90 222
Jeej 9:0140247bab90 223 int kal_buf_circ_peek(kal_buf_circ_handle_t handle, uint8_t* p)
Jeej 9:0140247bab90 224 {
Jeej 9:0140247bab90 225 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 226
Jeej 9:0140247bab90 227 // check if circular buffer is empty
Jeej 9:0140247bab90 228 if (kal_buf_circ_empty(handle))
Jeej 9:0140247bab90 229 {
Jeej 9:0140247bab90 230 return -1; // and return with an error
Jeej 9:0140247bab90 231 }
Jeej 9:0140247bab90 232
Jeej 9:0140247bab90 233 // Read data
Jeej 9:0140247bab90 234 memcpy(p, &(h->buffer[h->tail]), h->element_size);
Jeej 9:0140247bab90 235
Jeej 9:0140247bab90 236 // return success to indicate successful peek.
Jeej 9:0140247bab90 237 return 0;
Jeej 9:0140247bab90 238 }
Jeej 9:0140247bab90 239
Jeej 9:0140247bab90 240 int kal_buf_circ_put(kal_buf_circ_handle_t handle, uint8_t* p, uint32_t nb_elements)
Jeej 9:0140247bab90 241 {
Jeej 9:0140247bab90 242 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 243
Jeej 9:0140247bab90 244 // Check if there is enough available spots in the buffer
Jeej 9:0140247bab90 245 if (nb_elements + kal_buf_circ_size(handle) >= h->max_length / h->element_size)
Jeej 9:0140247bab90 246 {
Jeej 9:0140247bab90 247 return -1; // and return with an error
Jeej 9:0140247bab90 248 }
Jeej 9:0140247bab90 249
Jeej 9:0140247bab90 250 // check if write should be done in two parts
Jeej 9:0140247bab90 251 uint32_t available_now = (h->max_length - h->head) / h->element_size;
Jeej 9:0140247bab90 252 if (nb_elements > available_now)
Jeej 9:0140247bab90 253 {
Jeej 9:0140247bab90 254 // write first part up to max_length
Jeej 9:0140247bab90 255 if (kal_buf_circ_put(handle, p, available_now))
Jeej 9:0140247bab90 256 {
Jeej 9:0140247bab90 257 return -1;
Jeej 9:0140247bab90 258 }
Jeej 9:0140247bab90 259
Jeej 9:0140247bab90 260 // increment write pointer
Jeej 9:0140247bab90 261 p += available_now * h->element_size;
Jeej 9:0140247bab90 262 // subtract what we just wrote
Jeej 9:0140247bab90 263 nb_elements -= available_now;
Jeej 9:0140247bab90 264 }
Jeej 9:0140247bab90 265
Jeej 9:0140247bab90 266 // next is where head will point to after this write.
Jeej 9:0140247bab90 267 uint32_t next = kal_buf_circ_next_head(h, nb_elements);
Jeej 9:0140247bab90 268
Jeej 9:0140247bab90 269 // write data
Jeej 9:0140247bab90 270 memcpy(&(h->buffer[h->head]), p, nb_elements * h->element_size);
Jeej 9:0140247bab90 271
Jeej 9:0140247bab90 272 // head to next data offset.
Jeej 9:0140247bab90 273 h->head = next;
Jeej 9:0140247bab90 274
Jeej 9:0140247bab90 275 // return success to indicate successful get.
Jeej 9:0140247bab90 276 return 0;
Jeej 9:0140247bab90 277 }
Jeej 9:0140247bab90 278
Jeej 9:0140247bab90 279 int kal_buf_circ_get(kal_buf_circ_handle_t handle, uint8_t* p, uint32_t nb_elements)
Jeej 9:0140247bab90 280 {
Jeej 9:0140247bab90 281 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 282
Jeej 9:0140247bab90 283 // Check if there is enough elements in the buffer
Jeej 9:0140247bab90 284 if (nb_elements > kal_buf_circ_size(handle))
Jeej 9:0140247bab90 285 {
Jeej 9:0140247bab90 286 return -1; // and return with an error
Jeej 9:0140247bab90 287 }
Jeej 9:0140247bab90 288
Jeej 9:0140247bab90 289 // check if read should be done in two parts
Jeej 9:0140247bab90 290 uint32_t available_now = (h->max_length - h->tail) / h->element_size;
Jeej 9:0140247bab90 291 if (nb_elements > available_now)
Jeej 9:0140247bab90 292 {
Jeej 9:0140247bab90 293 // get first part up to max_length
Jeej 9:0140247bab90 294 if (kal_buf_circ_get(handle, p, available_now))
Jeej 9:0140247bab90 295 {
Jeej 9:0140247bab90 296 return -1;
Jeej 9:0140247bab90 297 }
Jeej 9:0140247bab90 298
Jeej 9:0140247bab90 299 if (p)
Jeej 9:0140247bab90 300 {
Jeej 9:0140247bab90 301 // increment read pointer
Jeej 9:0140247bab90 302 p += available_now * h->element_size;
Jeej 9:0140247bab90 303 }
Jeej 9:0140247bab90 304 // subtract what we just read
Jeej 9:0140247bab90 305 nb_elements -= available_now;
Jeej 9:0140247bab90 306 }
Jeej 9:0140247bab90 307
Jeej 9:0140247bab90 308 // next is where tail will point to after this read.
Jeej 9:0140247bab90 309 uint32_t next = kal_buf_circ_next_tail(h, nb_elements);
Jeej 9:0140247bab90 310
Jeej 9:0140247bab90 311 if (p)
Jeej 9:0140247bab90 312 {
Jeej 9:0140247bab90 313 // read data
Jeej 9:0140247bab90 314 memcpy(p, &(h->buffer[h->tail]), nb_elements * h->element_size);
Jeej 9:0140247bab90 315 }
Jeej 9:0140247bab90 316
Jeej 9:0140247bab90 317 // tail to next data offset.
Jeej 9:0140247bab90 318 h->tail = next;
Jeej 9:0140247bab90 319
Jeej 9:0140247bab90 320 // return success to indicate successful get.
Jeej 9:0140247bab90 321 return 0;
Jeej 9:0140247bab90 322 }
Jeej 9:0140247bab90 323
Jeej 9:0140247bab90 324 int kal_buf_circ_fetch(kal_buf_circ_handle_t handle, uint8_t* p, uint32_t nb_elements)
Jeej 9:0140247bab90 325 {
Jeej 9:0140247bab90 326 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 327
Jeej 9:0140247bab90 328 // Check if there is enough elements in the buffer
Jeej 9:0140247bab90 329 if (nb_elements > kal_buf_circ_size(handle))
Jeej 9:0140247bab90 330 {
Jeej 9:0140247bab90 331 return -1; // and return with an error
Jeej 9:0140247bab90 332 }
Jeej 9:0140247bab90 333
Jeej 9:0140247bab90 334 // check if read should be done in two parts
Jeej 9:0140247bab90 335 uint32_t available_now = (h->max_length - h->tail) / h->element_size;
Jeej 9:0140247bab90 336 if (nb_elements > available_now)
Jeej 9:0140247bab90 337 {
Jeej 9:0140247bab90 338 // get first part from tail up to max_length
Jeej 9:0140247bab90 339 memcpy(p, &(h->buffer[h->tail]), available_now * h->element_size);
Jeej 9:0140247bab90 340
Jeej 9:0140247bab90 341 // increment read pointer
Jeej 9:0140247bab90 342 p += available_now * h->element_size;
Jeej 9:0140247bab90 343
Jeej 9:0140247bab90 344 // subtract what we just read
Jeej 9:0140247bab90 345 nb_elements -= available_now;
Jeej 9:0140247bab90 346
Jeej 9:0140247bab90 347 // get second part from 0 up to remaining length
Jeej 9:0140247bab90 348 memcpy(p, &(h->buffer[0]), nb_elements * h->element_size);
Jeej 9:0140247bab90 349 }
Jeej 9:0140247bab90 350 else
Jeej 9:0140247bab90 351 {
Jeej 9:0140247bab90 352 // get data from tail
Jeej 9:0140247bab90 353 memcpy(p, &(h->buffer[h->tail]), nb_elements * h->element_size);
Jeej 9:0140247bab90 354 }
Jeej 9:0140247bab90 355
Jeej 9:0140247bab90 356 // return success to indicate successful fetch.
Jeej 9:0140247bab90 357 return 0;
Jeej 9:0140247bab90 358 }
Jeej 9:0140247bab90 359
Jeej 9:0140247bab90 360 int kal_buf_circ_erase(kal_buf_circ_handle_t handle)
Jeej 9:0140247bab90 361 {
Jeej 9:0140247bab90 362 kal_buf_circ_static_handle_t* h = (kal_buf_circ_static_handle_t*)handle;
Jeej 9:0140247bab90 363
Jeej 9:0140247bab90 364 // check if circular buffer is empty
Jeej 9:0140247bab90 365 if (kal_buf_circ_empty(handle))
Jeej 9:0140247bab90 366 {
Jeej 9:0140247bab90 367 return -1; // and return with an error
Jeej 9:0140247bab90 368 }
Jeej 9:0140247bab90 369
Jeej 9:0140247bab90 370 // head is at 0, we wrap back
Jeej 9:0140247bab90 371 if (h->head == 0)
Jeej 9:0140247bab90 372 {
Jeej 9:0140247bab90 373 h->head = h->max_length - h->element_size;
Jeej 9:0140247bab90 374 }
Jeej 9:0140247bab90 375 // else go back one element
Jeej 9:0140247bab90 376 else
Jeej 9:0140247bab90 377 {
Jeej 9:0140247bab90 378 h->head = h->head - h->element_size;
Jeej 9:0140247bab90 379 }
Jeej 9:0140247bab90 380
Jeej 9:0140247bab90 381 // return success to indicate successful erase.
Jeej 9:0140247bab90 382 return 0;
Jeej 9:0140247bab90 383 }