/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1999-2018. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* %CopyrightEnd%
*/
#ifndef __ERL_BITS_H__
#define __ERL_BITS_H__
/*
* This structure represents a SUB_BINARY.
*
* Note: The last field (orig) is not counted in arityval in the header.
* This simplifies garbage collection.
*/
typedef struct erl_sub_bin {
Eterm thing_word; /* Subtag SUB_BINARY_SUBTAG. */
Uint size; /* Binary size in bytes. */
Uint offs; /* Offset into original binary. */
byte bitsize;
byte bitoffs;
byte is_writable; /* The underlying binary is writable */
Eterm orig; /* Original binary (REFC or HEAP binary). */
} ErlSubBin;
/*
* This structure represents a binary to be matched.
*/
typedef struct erl_bin_match_buffer {
Eterm orig; /* Original binary term. */
byte* base; /* Current position in binary. */
Uint offset; /* Offset in bits. */
size_t size; /* Size of binary in bits. */
} ErlBinMatchBuffer;
struct erl_bits_state {
/*
* Used for building binaries.
*/
byte *byte_buf_;
int byte_buf_len_;
/*
* Used for building binaries using the new instruction set.
*/
byte* erts_current_bin_; /* Pointer to beginning of current binary. */
/*
* Offset in bits into the current binary (new instruction set) or
* buffer (old instruction set).
*/
Uint erts_bin_offset_;
/*
* Whether the current binary is writable.
*/
unsigned erts_writable_bin_;
};
typedef struct erl_bin_match_struct{
Eterm thing_word;
ErlBinMatchBuffer mb; /* Present match buffer */
Eterm save_offset[1]; /* Saved offsets, only valid for contexts
* created through bs_start_match2. */
} ErlBinMatchState;
#define ERL_BIN_MATCHSTATE_SIZE(_Max) \
((offsetof(ErlBinMatchState, save_offset) + (_Max)*sizeof(Eterm))/sizeof(Eterm))
#define HEADER_BIN_MATCHSTATE(_Max) \
_make_header(ERL_BIN_MATCHSTATE_SIZE((_Max)) - 1, _TAG_HEADER_BIN_MATCHSTATE)
#define HEADER_NUM_SLOTS(hdr) \
(header_arity(hdr) - (offsetof(ErlBinMatchState, save_offset) / sizeof(Eterm)) + 1)
#define make_matchstate(_Ms) make_boxed((Eterm*)(_Ms))
#define ms_matchbuffer(_Ms) &(((ErlBinMatchState*) boxed_val(_Ms))->mb)
/*
* Reentrant API with the state passed as a parameter.
* (Except when the current Process* already is a parameter.)
*/
/* the state resides in the current process' scheduler data */
#define ERL_BITS_DECLARE_STATEP struct erl_bits_state *EBS
#define ERL_BITS_RELOAD_STATEP(P) do{EBS = &erts_proc_sched_data((P))->erl_bits_state;}while(0)
#define ERL_BITS_DEFINE_STATEP(P) struct erl_bits_state *EBS = &erts_proc_sched_data((P))->erl_bits_state
#define ErlBitsState (*EBS)
#define ERL_BITS_PROTO_0 struct erl_bits_state *EBS
#define ERL_BITS_PROTO_1(PARM1) struct erl_bits_state *EBS, PARM1
#define ERL_BITS_PROTO_2(PARM1,PARM2) struct erl_bits_state *EBS, PARM1, PARM2
#define ERL_BITS_PROTO_3(PARM1,PARM2,PARM3) struct erl_bits_state *EBS, PARM1, PARM2, PARM3
#define ERL_BITS_ARGS_0 EBS
#define ERL_BITS_ARGS_1(ARG1) EBS, ARG1
#define ERL_BITS_ARGS_2(ARG1,ARG2) EBS, ARG1, ARG2
#define ERL_BITS_ARGS_3(ARG1,ARG2,ARG3) EBS, ARG1, ARG2, ARG3
#define erts_bin_offset (ErlBitsState.erts_bin_offset_)
#define erts_current_bin (ErlBitsState.erts_current_bin_)
#define erts_writable_bin (ErlBitsState.erts_writable_bin_)
#define copy_binary_to_buffer(DstBuffer, DstBufOffset, SrcBuffer, SrcBufferOffset, NumBits) \
do { \
if (BIT_OFFSET(DstBufOffset) == 0 && (SrcBufferOffset == 0) && \
(BIT_OFFSET(NumBits)==0) && (NumBits != 0)) { \
sys_memcpy(((byte*)DstBuffer)+BYTE_OFFSET(DstBufOffset), \
SrcBuffer, NBYTES(NumBits)); \
} else { \
erts_copy_bits(SrcBuffer, SrcBufferOffset, 1, \
(byte*)DstBuffer, DstBufOffset, 1, NumBits); \
} \
} while (0)
void erts_init_bits(void); /* Initialization once. */
void erts_bits_init_state(ERL_BITS_PROTO_0);
void erts_bits_destroy_state(ERL_BITS_PROTO_0);
/*
* NBYTES(x) returns the number of bytes needed to store x bits.
*/
#define NBYTES(x) (((Uint64)(x) + (Uint64) 7) >> 3)
#define BYTE_OFFSET(ofs) ((Uint) (ofs) >> 3)
#define BIT_OFFSET(ofs) ((ofs) & 7)
/*
* Return number of Eterm words needed for allocation with HAlloc(),
* given a number of bytes.
*/
#define WSIZE(n) ((n + sizeof(Eterm) - 1) / sizeof(Eterm))
/*
* Binary matching.
*/
Eterm erts_bs_start_match_2(Process *p, Eterm Bin, Uint Max);
ErlBinMatchState *erts_bs_start_match_3(Process *p, Eterm Bin);
Eterm erts_bs_get_integer_2(Process *p, Uint num_bits, unsigned flags, ErlBinMatchBuffer* mb);
Eterm erts_bs_get_float_2(Process *p, Uint num_bits, unsigned flags, ErlBinMatchBuffer* mb);
/* These will create heap binaries when appropriate, so they require free space
* up to EXTRACT_SUB_BIN_HEAP_NEED. */
Eterm erts_bs_get_binary_2(Process *p, Uint num_bits, unsigned flags, ErlBinMatchBuffer* mb);
Eterm erts_bs_get_binary_all_2(Process *p, ErlBinMatchBuffer* mb);
/*
* Binary construction, new instruction set.
*/
int erts_new_bs_put_integer(ERL_BITS_PROTO_3(Eterm Integer, Uint num_bits, unsigned flags));
int erts_bs_put_utf8(ERL_BITS_PROTO_1(Eterm Integer));
int erts_bs_put_utf16(ERL_BITS_PROTO_2(Eterm Integer, Uint flags));
int erts_new_bs_put_binary(ERL_BITS_PROTO_2(Eterm Bin, Uint num_bits));
int erts_new_bs_put_binary_all(ERL_BITS_PROTO_2(Eterm Bin, Uint unit));
int erts_new_bs_put_float(Process *c_p, Eterm Float, Uint num_bits, int flags);
void erts_new_bs_put_string(ERL_BITS_PROTO_2(byte* iptr, Uint num_bytes));
Uint erts_bits_bufs_size(void);
Uint32 erts_bs_get_unaligned_uint32(ErlBinMatchBuffer* mb);
Eterm erts_bs_get_utf8(ErlBinMatchBuffer* mb);
Eterm erts_bs_get_utf16(ErlBinMatchBuffer* mb, Uint flags);
Eterm erts_bs_append(Process* p, Eterm* reg, Uint live, Eterm build_size_term,
Uint extra_words, Uint unit);
Eterm erts_bs_private_append(Process* p, Eterm bin, Eterm sz, Uint unit);
Eterm erts_bs_init_writable(Process* p, Eterm sz);
/*
* Common utilities.
*/
void erts_copy_bits(byte* src, size_t soffs, int sdir,
byte* dst, size_t doffs,int ddir, size_t n);
int erts_cmp_bits(byte* a_ptr, size_t a_offs, byte* b_ptr, size_t b_offs, size_t size);
/* Extracts a region from base_bin as a sub-binary or heap binary, whichever
* is the most appropriate.
*
* The caller must ensure that there's enough free space at *hp */
Eterm erts_extract_sub_binary(Eterm **hp, Eterm base_bin, byte *base_data,
Uint bit_offset, Uint num_bits);
/* Pessimistic estimate of the words required for erts_extract_sub_binary */
#define EXTRACT_SUB_BIN_HEAP_NEED (heap_bin_size(ERL_ONHEAP_BIN_LIMIT))
/*
* Flags for bs_get_* / bs_put_* / bs_init* instructions.
*/
#define BSF_ALIGNED 1 /* Field is guaranteed to be byte-aligned. */
#define BSF_LITTLE 2 /* Field is little-endian (otherwise big-endian). */
#define BSF_SIGNED 4 /* Field is signed (otherwise unsigned). */
#define BSF_EXACT 8 /* Size in bs_init is exact. */
#define BSF_NATIVE 16 /* Native endian. */
#endif /* __ERL_BITS_H__ */
