nghttp2/lib/nghttp2_hd.h

242 lines
8.4 KiB
C

/*
* nghttp2 - HTTP/2.0 C Library
*
* Copyright (c) 2013 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_HD_COMP_H
#define NGHTTP2_HD_COMP_H
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */
#include <nghttp2/nghttp2.h>
#define NGHTTP2_INITIAL_HD_TABLE_SIZE 128
#define NGHTTP2_INITIAL_EMIT_SET_SIZE 128
#define NGHTTP2_HD_MAX_BUFFER_SIZE 4096
#define NGHTTP2_HD_MAX_ENTRY_SIZE 3072
#define NGHTTP2_HD_ENTRY_OVERHEAD 32
/* This value is sensible to NGHTTP2_HD_MAX_BUFFER_SIZE. Currently,
the index is at most 128, so 255 is good choice */
#define NGHTTP2_HD_INVALID_INDEX 255
typedef enum {
NGHTTP2_HD_SIDE_CLIENT = 0,
NGHTTP2_HD_SIDE_SERVER = 1
} nghttp2_hd_side;
typedef enum {
NGHTTP2_HD_ROLE_DEFLATE,
NGHTTP2_HD_ROLE_INFLATE
} nghttp2_hd_role;
typedef enum {
NGHTTP2_HD_FLAG_NONE = 0,
/* Indicates name was dynamically allocated and must be freed */
NGHTTP2_HD_FLAG_NAME_ALLOC = 1,
/* Indicates value was dynamically allocated and must be freed */
NGHTTP2_HD_FLAG_VALUE_ALLOC = 1 << 1,
/* Indicates that the entry is in the reference set */
NGHTTP2_HD_FLAG_REFSET = 1 << 2,
/* Indicates that the entry is emitted in the current header
processing. */
NGHTTP2_HD_FLAG_EMIT = 1 << 3,
NGHTTP2_HD_FLAG_IMPLICIT_EMIT = 1 << 4
} nghttp2_hd_flags;
typedef struct {
nghttp2_nv nv;
/* Reference count */
uint8_t ref;
/* Index in the header table */
uint8_t index;
uint8_t flags;
} nghttp2_hd_entry;
typedef struct {
/* Header table */
nghttp2_hd_entry **hd_table;
/* Holding emitted entry in deflating header block to retain
reference count. */
nghttp2_hd_entry **emit_set;
/* The capacity of the |hd_table| */
uint16_t hd_table_capacity;
/* The number of entry the |hd_table| contains */
uint16_t hd_tablelen;
/* The capacity of the |emit_set| */
uint16_t emit_set_capacity;
/* The number of entry the |emit_set| contains */
uint16_t emit_setlen;
/* Abstract buffer size of hd_table as described in the spec. This
is the sum of length of name/value in hd_table +
NGHTTP2_HD_ENTRY_OVERHEAD bytes overhead per each entry. */
uint16_t hd_table_bufsize;
/* If inflate/deflate error occurred, this value is set to 1 and
further invocation of inflate/deflate will fail with
NGHTTP2_ERR_HEADER_COMP. */
uint8_t bad;
/* Role of this context; deflate or infalte */
nghttp2_hd_role role;
} nghttp2_hd_context;
/*
* Initializes the |ent| members. If NGHTTP2_HD_FLAG_NAME_ALLOC bit
* set in the |flags|, the content pointed by the |name| with length
* |namelen| is copied. Likewise, if NGHTTP2_HD_FLAG_VALUE_ALLOC bit
* set in the |flags|, the content pointed by the |value| with length
* |valuelen| is copied.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_hd_entry_init(nghttp2_hd_entry *ent, uint8_t index, uint8_t flags,
uint8_t *name, uint16_t namelen,
uint8_t *value, uint16_t valuelen);
void nghttp2_hd_entry_free(nghttp2_hd_entry *ent);
/*
* Initializes |deflater| for deflating name/values pairs.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_hd_deflate_init(nghttp2_hd_context *deflater,
nghttp2_hd_side side);
/*
* Initializes |inflater| for inflating name/values pairs.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
int nghttp2_hd_inflate_init(nghttp2_hd_context *inflater,
nghttp2_hd_side side);
/*
* Deallocates any resources allocated for |deflater|.
*/
void nghttp2_hd_deflate_free(nghttp2_hd_context *deflater);
/*
* Deallocates any resources allocated for |inflater|.
*/
void nghttp2_hd_inflate_free(nghttp2_hd_context *inflater);
/*
* Deflates the |nva|, which has the |nvlen| name/value pairs, into
* the buffer pointed by the |*buf_ptr| with the length |*buflen_ptr|.
* The output starts after |nv_offset| bytes from |*buf_ptr|.
*
* This function expands |*buf_ptr| as necessary to store the
* result. When expansion occurred, memory previously pointed by
* |*buf_ptr| may change. |*buf_ptr| and |*buflen_ptr| are updated
* accordingly.
*
* This function copies necessary data into |*buf_ptr|. After this
* function returns, it is safe to delete the |nva|.
*
* TODO: The rest of the code call nghttp2_hd_end_headers() after this
* call, but it is just a regacy of the first implementation. Now it
* is not required to be called as of now.
*
* This function returns the number of bytes outputted if it succeeds,
* or one of the following negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_HEADER_COMP
* Deflation process has failed.
*/
ssize_t nghttp2_hd_deflate_hd(nghttp2_hd_context *deflater,
uint8_t **buf_ptr, size_t *buflen_ptr,
size_t nv_offset,
nghttp2_nv *nva, size_t nvlen);
/*
* Inflates name/value block stored in |in| with length |inlen|. This
* function performs decompression. The |*nva_ptr| points to the final
* result on successful decompression. The caller must free |*nva_ptr|
* using nghttp2_nv_array_del().
*
* The |*nva_ptr| includes pointers to the memory region in the
* |in|. The caller must retain the |in| while the |*nva_ptr| is
* used. After the use of |*nva_ptr| is over, if the caller intends to
* inflate another set of headers, the caller must call
* nghttp2_hd_end_headers().
*
* This function returns the number of name/value pairs in |*nva_ptr|
* if it succeeds, or one of the following negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
* NGHTTP2_ERR_HEADER_COMP
* Inflation process has failed.
*/
ssize_t nghttp2_hd_inflate_hd(nghttp2_hd_context *inflater,
nghttp2_nv **nva_ptr,
uint8_t *in, size_t inlen);
/*
* Signals the end of processing one header block.
*
* This function returns 0 if it succeeds. Currently this function
* always succeeds.
*/
int nghttp2_hd_end_headers(nghttp2_hd_context *deflater_or_inflater);
/* For unittesting purpose */
int nghttp2_hd_emit_indname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, size_t index,
const uint8_t *value, size_t valuelen,
int inc_indexing);
/* For unittesting purpose */
int nghttp2_hd_emit_newname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, nghttp2_nv *nv,
int inc_indexing);
/* For unittesting purpose */
int nghttp2_hd_emit_subst_indname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, size_t index,
const uint8_t *value, size_t valuelen,
size_t subindex);
/* For unittesting purpose */
int nghttp2_hd_emit_subst_newname_block(uint8_t **buf_ptr, size_t *buflen_ptr,
size_t *offset_ptr, nghttp2_nv *nv,
size_t subindex);
#endif /* NGHTTP2_HD_COMP_H */