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Diffstat (limited to 'src/ring.c')
| -rw-r--r-- | src/ring.c | 224 |
1 files changed, 0 insertions, 224 deletions
diff --git a/src/ring.c b/src/ring.c deleted file mode 100644 index 13cf8c9..0000000 --- a/src/ring.c +++ /dev/null @@ -1,224 +0,0 @@ -/** - * coopgammad -- Cooperative gamma server - * Copyright (C) 2016 Mattias Andrée (maandree@kth.se) - * - * This program is free software: you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation, either version 3 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ -#include "ring.h" - -#include <stdlib.h> -#include <string.h> - - - -/** - * Initialise a ring buffer - * - * @param this The ring buffer - */ -void ring_initialise(struct ring* restrict this) -{ - this->start = 0; - this->end = 0; - this->size = 0; - this->buffer = NULL; -} - - -/** - * Release resource allocated to a ring buffer - * - * @param this The ring buffer - */ -void ring_destroy(struct ring* restrict this) -{ - free(this->buffer); -} - - - -#if defined(__clang__) -# pragma GCC diagnostic push -# pragma GCC diagnostic ignored "-Wcast-align" -#endif - - -/** - * Marshal a ring buffer - * - * @param this The ring buffer - * @param buf Output buffer for the marshalled data, - * `NULL` to only measure how large buffer - * is needed - * @return The number of marshalled bytes - */ -size_t ring_marshal(const struct ring* restrict this, void* restrict buf) -{ - size_t off = 0, n = this->end - this->start; - char* bs = buf; - - if (bs != NULL) - *(size_t*)(bs + off) = n; - off += sizeof(size_t); - - if (bs != NULL) - memcpy(bs + off, this->buffer + this->start, n); - off += n; - - return off; -} - - -/** - * Unmarshal a ring buffer - * - * @param this Output parameter for the ring buffer - * @param buf Buffer with the marshalled data - * @return The number of unmarshalled bytes, 0 on error - */ -size_t ring_unmarshal(struct ring* restrict this, const void* restrict buf) -{ - size_t off = 0; - const char* bs = buf; - - ring_initialise(this); - - this->size = this->end = *(const size_t*)(bs + off); - off += sizeof(size_t); - - if (this->end > 0) - { - if (!(this->buffer = malloc(this->end))) - return 0; - - memcpy(this->buffer, bs + off, this->end); - off += this->end; - } - - return off; -} - - -#if defined(__clang__) -# pragma GCC diagnostic pop -#endif - - - -/** - * Append data to a ring buffer - * - * @param this The ring buffer - * @param data The new data - * @param n The number of bytes in `data` - * @return Zero on success, -1 on error - */ -int ring_push(struct ring* restrict this, void* restrict data, size_t n) -{ - size_t used = 0; - - if (this->start == this->end) - { - if (this->buffer != NULL) - used = this->size; - } - else if (this->start > this->end) - used = this->size - this->start + this->end; - else - used = this->start - this->end; - - if (used + n > this->size) - { - char* restrict new = malloc(used + n); - if (new == NULL) - return -1; - if (this->buffer) - { - if (this->start < this->end) - memcpy(new, this->buffer + this->start, this->end - this->start); - else - { - memcpy(new, this->buffer + this->start, this->size - this->start); - memcpy(new + this->size - this->start, this->buffer, this->end); - } - } - memcpy(new + used, data, n); - this->buffer = new; - this->start = 0; - this->end = used + n; - this->size = used + n; - } - else if ((this->start >= this->end) || (this->end + n <= this->size)) - { - memcpy(this->buffer + this->end, data, n); - this->end += n; - } - else - { - memcpy(this->buffer + this->end, data, this->size - this->end); - data = (char*)data + (this->size - this->end); - n -= this->size - this->end; - memcpy(this->buffer, data, n); - this->end = n; - } - - return 0; -} - - -/** - * Get queued data from a ring buffer - * - * It can take up to two calls (with `ring_pop` between) - * to get all queued data - * - * @param this The ring buffer - * @param n Output parameter for the length - * of the returned segment - * @return The beginning of the queued data, - * `NULL` if there is nothing more - */ -void* ring_peek(struct ring* restrict this, size_t* restrict n) -{ - if (this->buffer == NULL) - return *n = 0, NULL; - - if (this->start < this->end) - *n = this->end - this->start; - else - *n = this->size - this->start; - return this->buffer + this->start; -} - - -/** - * Dequeue data from a ring bubber - * - * @param this The ring buffer - * @param n The number of bytes to dequeue - */ -void ring_pop(struct ring* restrict this, size_t n) -{ - this->start += n; - this->start %= this->size; - if (this->start == this->end) - { - free(this->buffer); - this->start = 0; - this->end = 0; - this->size = 0; - this->buffer = NULL; - } -} - |