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mirror of https://github.com/janet-lang/janet synced 2024-11-14 20:54:48 +00:00
janet/core/buffer.c
2017-11-05 22:05:47 -05:00

142 lines
5.0 KiB
C

/*
* Copyright (c) 2017 Calvin Rose
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include <dst/dst.h>
/* Initialize a buffer */
DstBuffer *dst_buffer_init(DstBuffer *buffer, uint32_t capacity) {
uint8_t *data = malloc(sizeof(uint8_t) * capacity);
if (NULL == data) {
DST_OUT_OF_MEMORY;
}
buffer->count = 0;
buffer->capacity = capacity;
return buffer;
}
/* Deinitialize a buffer (free data memory) */
void dst_buffer_deinit(DstBuffer *buffer) {
free(buffer->data);
}
/* Initialize a buffer */
DstBuffer *dst_buffer(uint32_t capacity) {
DstBuffer *buffer = dst_alloc(DST_MEMORY_BUFFER, sizeof(DstBuffer));
return dst_buffer_init(buffer, capacity);
}
/* Ensure that the buffer has enough internal capacity */
void dst_buffer_ensure(DstBuffer *buffer, uint32_t capacity) {
uint8_t *newData;
uint8_t *old = buffer->data;
if (capacity <= buffer->capacity) return;
newData = realloc(old, capacity * sizeof(uint8_t));
if (NULL == newData) {
DST_OUT_OF_MEMORY;
}
buffer->data = newData;
buffer->capacity = capacity;
}
/* Adds capacity for enough extra bytes to the buffer. Ensures that the
* next n bytes pushed to the buffer will not cause a reallocation */
void dst_buffer_extra(DstBuffer *buffer, uint32_t n) {
uint32_t newCount = buffer->count + n;
if (newCount > buffer->capacity) {
uint32_t newCapacity = newCount * 2;
uint8_t *newData = realloc(buffer->data, newCapacity * sizeof(uint8_t));
if (NULL == newData) {
DST_OUT_OF_MEMORY;
}
buffer->data = newData;
buffer->capacity = newCapacity;
}
}
/* Push multiple bytes into the buffer */
void dst_buffer_push_bytes(DstBuffer *buffer, const uint8_t *string, uint32_t length) {
uint32_t newSize = buffer->count + length;
if (newSize > buffer->capacity) {
dst_buffer_ensure(buffer, 2 * newSize);
}
memcpy(buffer->data + buffer->count, string, length);
buffer->count = newSize;
}
/* Push a cstring to buffer */
void dst_buffer_push_cstring(DstBuffer *buffer, const char *cstring) {
uint32_t len = 0;
while (cstring[len]) ++len;
dst_buffer_push_bytes(buffer, (const uint8_t *) cstring, len);
}
/* Push a single byte to the buffer */
void dst_buffer_push_u8(DstBuffer *buffer, uint8_t byte) {
uint32_t newSize = buffer->count + 1;
if (newSize > buffer->capacity) {
dst_buffer_ensure(buffer, 2 * newSize);
}
buffer->data[buffer->count] = byte;
buffer->count = newSize;
}
/* Push a 16 bit unsigned integer to the buffer */
void dst_buffer_push_u16(DstBuffer *buffer, uint16_t x) {
uint32_t newSize = buffer->count + 2;
if (newSize > buffer->capacity) {
dst_buffer_ensure(buffer, 2 * newSize);
}
buffer->data[buffer->count] = x & 0xFF;
buffer->data[buffer->count + 1] = (x >> 8) & 0xFF;
buffer->count = newSize;
}
/* Push a 32 bit unsigned integer to the buffer */
void dst_buffer_push_u32(DstBuffer *buffer, uint32_t x) {
uint32_t newSize = buffer->count + 4;
if (newSize > buffer->capacity) {
dst_buffer_ensure(buffer, 2 * newSize);
}
buffer->data[buffer->count] = x & 0xFF;
buffer->data[buffer->count + 1] = (x >> 8) & 0xFF;
buffer->data[buffer->count + 2] = (x >> 16) & 0xFF;
buffer->data[buffer->count + 3] = (x >> 24) & 0xFF;
buffer->count = newSize;
}
/* Push a 64 bit unsigned integer to the buffer */
void dst_buffer_push_u64(DstBuffer *buffer, uint64_t x) {
uint32_t newSize = buffer->count + 8;
if (newSize > buffer->capacity) {
dst_buffer_ensure(buffer, 2 * newSize);
}
buffer->data[buffer->count] = x & 0xFF;
buffer->data[buffer->count + 1] = (x >> 8) & 0xFF;
buffer->data[buffer->count + 2] = (x >> 16) & 0xFF;
buffer->data[buffer->count + 3] = (x >> 24) & 0xFF;
buffer->data[buffer->count + 4] = (x >> 32) & 0xFF;
buffer->data[buffer->count + 5] = (x >> 40) & 0xFF;
buffer->data[buffer->count + 6] = (x >> 48) & 0xFF;
buffer->data[buffer->count + 7] = (x >> 56) & 0xFF;
buffer->count = newSize;
}