nghttp2/lib/nghttp2_buf.h

386 lines
12 KiB
C

/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2014 Tatsuhiro Tsujikawa
*
* 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.
*/
#ifndef NGHTTP2_BUF_H
#define NGHTTP2_BUF_H
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /* HAVE_CONFIG_H */
#include <nghttp2/nghttp2.h>
#include "nghttp2_int.h"
#include "nghttp2_mem.h"
typedef struct {
/* This points to the beginning of the buffer. The effective range
of buffer is [begin, end). */
uint8_t *begin;
/* This points to the memory one byte beyond the end of the
buffer. */
uint8_t *end;
/* The position indicator for effective start of the buffer. pos <=
last must be hold. */
uint8_t *pos;
/* The position indicator for effective one beyond of the end of the
buffer. last <= end must be hold. */
uint8_t *last;
/* Mark arbitrary position in buffer [begin, end) */
uint8_t *mark;
} nghttp2_buf;
#define nghttp2_buf_len(BUF) ((ssize_t)((BUF)->last - (BUF)->pos))
#define nghttp2_buf_avail(BUF) ((ssize_t)((BUF)->end - (BUF)->last))
#define nghttp2_buf_mark_avail(BUF) ((ssize_t)((BUF)->mark - (BUF)->last))
#define nghttp2_buf_cap(BUF) ((ssize_t)((BUF)->end - (BUF)->begin))
#define nghttp2_buf_pos_offset(BUF) ((ssize_t)((BUF)->pos - (BUF)->begin))
#define nghttp2_buf_last_offset(BUF) ((ssize_t)((BUF)->last - (BUF)->begin))
#define nghttp2_buf_shift_right(BUF, AMT) \
do { \
(BUF)->pos += AMT; \
(BUF)->last += AMT; \
} while (0)
#define nghttp2_buf_shift_left(BUF, AMT) \
do { \
(BUF)->pos -= AMT; \
(BUF)->last -= AMT; \
} while (0)
/*
* Initializes the |buf|. No memory is allocated in this function. Use
* nghttp2_buf_reserve() or nghttp2_buf_reserve2() to allocate memory.
*/
void nghttp2_buf_init(nghttp2_buf *buf);
/*
* Initializes the |buf| and allocates at least |initial| bytes of
* memory.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_buf_init2(nghttp2_buf *buf, size_t initial, nghttp2_mem *mem);
/*
* Frees buffer in |buf|.
*/
void nghttp2_buf_free(nghttp2_buf *buf, nghttp2_mem *mem);
/*
* Extends buffer so that nghttp2_buf_cap() returns at least
* |new_cap|. If extensions took place, buffer pointers in |buf| will
* change.
*
* This function returns 0 if it succeeds, or one of the followings
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_buf_reserve(nghttp2_buf *buf, size_t new_cap, nghttp2_mem *mem);
/*
* Resets pos, last, mark member of |buf| to buf->begin.
*/
void nghttp2_buf_reset(nghttp2_buf *buf);
/*
* Initializes |buf| using supplied buffer |begin| of length
* |len|. Semantically, the application should not call *_reserve() or
* nghttp2_free() functions for |buf|.
*/
void nghttp2_buf_wrap_init(nghttp2_buf *buf, uint8_t *begin, size_t len);
struct nghttp2_buf_chain;
typedef struct nghttp2_buf_chain nghttp2_buf_chain;
/* Chains 2 buffers */
struct nghttp2_buf_chain {
/* Points to the subsequent buffer. NULL if there is no such
buffer. */
nghttp2_buf_chain *next;
nghttp2_buf buf;
};
typedef struct {
/* Points to the first buffer */
nghttp2_buf_chain *head;
/* Buffer pointer where write occurs. */
nghttp2_buf_chain *cur;
/* Memory allocator */
nghttp2_mem *mem;
/* The buffer capacity of each buf */
size_t chunk_length;
/* The maximum number of nghttp2_buf_chain */
size_t max_chunk;
/* The number of nghttp2_buf_chain allocated */
size_t chunk_used;
/* The number of nghttp2_buf_chain to keep on reset */
size_t chunk_keep;
/* pos offset from begin in each buffers. On initialization and
reset, buf->pos and buf->last are positioned at buf->begin +
offset. */
size_t offset;
} nghttp2_bufs;
/*
* This is the same as calling nghttp2_bufs_init2 with the given
* arguments and offset = 0.
*/
int nghttp2_bufs_init(nghttp2_bufs *bufs, size_t chunk_length, size_t max_chunk,
nghttp2_mem *mem);
/*
* This is the same as calling nghttp2_bufs_init3 with the given
* arguments and chunk_keep = max_chunk.
*/
int nghttp2_bufs_init2(nghttp2_bufs *bufs, size_t chunk_length,
size_t max_chunk, size_t offset, nghttp2_mem *mem);
/*
* Initializes |bufs|. Each buffer size is given in the
* |chunk_length|. The maximum number of buffers is given in the
* |max_chunk|. On reset, first |chunk_keep| buffers are kept and
* remaining buffers are deleted. Each buffer will have bufs->pos and
* bufs->last shifted to left by |offset| bytes on creation and reset.
*
* This function allocates first buffer. bufs->head and bufs->cur
* will point to the first buffer after this call.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_INVALID_ARGUMENT
* chunk_keep is 0; or max_chunk < chunk_keep; or offset is too
* long.
*/
int nghttp2_bufs_init3(nghttp2_bufs *bufs, size_t chunk_length,
size_t max_chunk, size_t chunk_keep, size_t offset,
nghttp2_mem *mem);
/*
* Frees any related resources to the |bufs|.
*/
void nghttp2_bufs_free(nghttp2_bufs *bufs);
/*
* Initializes |bufs| using supplied buffer |begin| of length |len|.
* The first buffer bufs->head uses buffer |begin|. The buffer size
* is fixed and no allocate extra chunk buffer is allocated. In other
* words, max_chunk = chunk_keep = 1. To free the resource allocated
* for |bufs|, use nghttp2_bufs_wrap_free().
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_bufs_wrap_init(nghttp2_bufs *bufs, uint8_t *begin, size_t len,
nghttp2_mem *mem);
/*
* Frees any related resource to the |bufs|. This function does not
* free supplied buffer provided in nghttp2_bufs_wrap_init().
*/
void nghttp2_bufs_wrap_free(nghttp2_bufs *bufs);
/*
* Reallocates internal buffer using |chunk_length|. The max_chunk,
* chunk_keep and offset do not change. After successful allocation
* of new buffer, previous buffers are deallocated without copying
* anything into new buffers. chunk_used is reset to 1.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_INVALID_ARGUMENT
* chunk_length < offset
*/
int nghttp2_bufs_realloc(nghttp2_bufs *bufs, size_t chunk_length);
/*
* Appends the |data| of length |len| to the |bufs|. The write starts
* at bufs->cur->buf.last. A new buffers will be allocated to store
* all data.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_BUFFER_ERROR
* Out of buffer space.
*/
int nghttp2_bufs_add(nghttp2_bufs *bufs, const void *data, size_t len);
/*
* Appends a single byte |b| to the |bufs|. The write starts at
* bufs->cur->buf.last. A new buffers will be allocated to store all
* data.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_BUFFER_ERROR
* Out of buffer space.
*/
int nghttp2_bufs_addb(nghttp2_bufs *bufs, uint8_t b);
/*
* Behaves like nghttp2_bufs_addb(), but this does not update
* buf->last pointer.
*/
int nghttp2_bufs_addb_hold(nghttp2_bufs *bufs, uint8_t b);
#define nghttp2_bufs_fast_addb(BUFS, B) \
do { \
*(BUFS)->cur->buf.last++ = B; \
} while (0)
#define nghttp2_bufs_fast_addb_hold(BUFS, B) \
do { \
*(BUFS)->cur->buf.last = B; \
} while (0)
/*
* Performs bitwise-OR of |b| at bufs->cur->buf.last. A new buffers
* will be allocated if necessary.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_BUFFER_ERROR
* Out of buffer space.
*/
int nghttp2_bufs_orb(nghttp2_bufs *bufs, uint8_t b);
/*
* Behaves like nghttp2_bufs_orb(), but does not update buf->last
* pointer.
*/
int nghttp2_bufs_orb_hold(nghttp2_bufs *bufs, uint8_t b);
#define nghttp2_bufs_fast_orb(BUFS, B) \
do { \
*(BUFS)->cur->buf.last++ |= B; \
} while (0)
#define nghttp2_bufs_fast_orb_hold(BUFS, B) \
do { \
*(BUFS)->cur->buf.last |= B; \
} while (0)
/*
* Copies all data stored in |bufs| to the contagious buffer. This
* function allocates the contagious memory to store all data in
* |bufs| and assigns it to |*out|.
*
* The contents of |bufs| is left unchanged.
*
* This function returns the length of copied data and assigns the
* pointer to copied data to |*out| if it succeeds, or one of the
* following negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
ssize_t nghttp2_bufs_remove(nghttp2_bufs *bufs, uint8_t **out);
/*
* Copies all data stored in |bufs| to |out|. This function assumes
* that the buffer space pointed by |out| has at least
* nghttp2_bufs(bufs) bytes.
*
* The contents of |bufs| is left unchanged.
*
* This function returns the length of copied data.
*/
size_t nghttp2_bufs_remove_copy(nghttp2_bufs *bufs, uint8_t *out);
/*
* Resets |bufs| and makes the buffers empty.
*/
void nghttp2_bufs_reset(nghttp2_bufs *bufs);
/*
* Moves bufs->cur to bufs->cur->next. If resulting bufs->cur is
* NULL, this function allocates new buffers and bufs->cur points to
* it.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
* NGHTTP2_ERR_BUFFER_ERROR
* Out of buffer space.
*/
int nghttp2_bufs_advance(nghttp2_bufs *bufs);
/* Sets bufs->cur to bufs->head */
#define nghttp2_bufs_rewind(BUFS) \
do { \
(BUFS)->cur = (BUFS)->head; \
} while (0)
/*
* Move bufs->cur, from the current position, using next member, to
* the last buf which has nghttp2_buf_len(buf) > 0 without seeing buf
* which satisfies nghttp2_buf_len(buf) == 0. If
* nghttp2_buf_len(&bufs->cur->buf) == 0 or bufs->cur->next is NULL,
* bufs->cur is unchanged.
*/
void nghttp2_bufs_seek_last_present(nghttp2_bufs *bufs);
/*
* Returns nonzero if bufs->cur->next is not emtpy.
*/
int nghttp2_bufs_next_present(nghttp2_bufs *bufs);
#define nghttp2_bufs_cur_avail(BUFS) nghttp2_buf_avail(&(BUFS)->cur->buf)
/*
* Returns the buffer length of |bufs|.
*/
ssize_t nghttp2_bufs_len(nghttp2_bufs *bufs);
#endif /* NGHTTP2_BUF_H */