diff options
Diffstat (limited to 'src/common/include/buffer.h')
-rw-r--r-- | src/common/include/buffer.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/src/common/include/buffer.h b/src/common/include/buffer.h new file mode 100644 index 0000000..0d6cfbf --- /dev/null +++ b/src/common/include/buffer.h @@ -0,0 +1,41 @@ +#pragma once + +#include <stdint.h> +#include <stddef.h> +#include <stdbool.h> + +// The buffer_t type is a simple reference-counted buffer type +// enabling the creation, sharing, slicing and concatenation of buffers +// without having to copy everything each time + +// Buffers are always allocated on the core kernel heap (kmalloc/kfree) + +// Once a buffer is allocated, its contents is immutable + +// Encoding and decoding functions for buffer contents are provided in +// a separate file (encode.h) + +struct buffer; +typedef struct buffer buffer_t; + +void buffer_ref(buffer_t*); // increase reference counter +void buffer_unref(buffer_t*); // decrease reference counter + +size_t buffer_len(buffer_t* buf); +size_t read_buffer(buffer_t* buf, char* to, size_t begin, size_t n); // returns num of bytes read + +buffer_t* buffer_from_bytes(const char* data, size_t n); // bytes are COPIED +buffer_t* buffer_from_bytes_nocopy(const char* data, size_t n, bool own_bytes); // bytes are NOT COPIED + +// these functions GIVE the buffer in order to create the new buffer, ie they do not increase RC +// the buffer is NOT GIVED if the new buffer could not be created (ie retval == 0) +buffer_t* buffer_slice(buffer_t* b, size_t begin, size_t n); +buffer_t* buffer_concat(buffer_t* a, buffer_t* b); + +// these functions KEEP a reference on the buffer (ie RC is incremented) +// the RC is NOT INCREMENTED if the new buffer cannot be created +buffer_t* buffer_slice_k(buffer_t* b, size_t begin, size_t n); +buffer_t* buffer_concat_k(buffer_t* a, buffer_t* b); + + +/* vim: set ts=4 sw=4 tw=0 noet :*/ |