/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1996-2018. 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 __ATOM_H__
#define __ATOM_H__
#include "index.h"
#include "erl_atom_table.h"
#define MAX_ATOM_CHARACTERS 255
#define MAX_ATOM_SZ_FROM_LATIN1 (2*MAX_ATOM_CHARACTERS)
#define MAX_ATOM_SZ_LIMIT (4*MAX_ATOM_CHARACTERS) /* theoretical byte limit */
#define ATOM_LIMIT (1024*1024)
#define MIN_ATOM_TABLE_SIZE 8192
#define ATOM_BAD_ENCODING_ERROR -1
#define ATOM_MAX_CHARS_ERROR -2
#ifndef ARCH_32
/* Internal atom cache needs MAX_ATOM_TABLE_SIZE to be less than an
unsigned 32 bit integer. See external.c(erts_encode_ext_dist_header_setup)
for more details. */
#define MAX_ATOM_TABLE_SIZE ((MAX_ATOM_INDEX + 1 < (UWORD_CONSTANT(1) << 32)) ? MAX_ATOM_INDEX + 1 : ((UWORD_CONSTANT(1) << 31) - 1)) /* Here we use maximum signed interger value to avoid integer overflow */
#else
#define MAX_ATOM_TABLE_SIZE (MAX_ATOM_INDEX + 1)
#endif
/*
* Atom entry.
*/
typedef struct atom {
IndexSlot slot; /* MUST BE LOCATED AT TOP OF STRUCT!!! */
Sint16 len; /* length of atom name (UTF-8 encoded) */
Sint16 latin1_chars; /* 0-255 if atom can be encoded in latin1; otherwise, -1 */
int ord0; /* ordinal value of first 3 bytes + 7 bits */
byte* name; /* name of atom */
} Atom;
extern IndexTable erts_atom_table;
ERTS_GLB_INLINE Atom* atom_tab(Uint i);
ERTS_GLB_INLINE int erts_is_atom_utf8_bytes(byte *text, size_t len, Eterm term);
ERTS_GLB_INLINE int erts_is_atom_str(const char *str, Eterm term, int is_latin1);
#if ERTS_GLB_INLINE_INCL_FUNC_DEF
ERTS_GLB_INLINE Atom*
atom_tab(Uint i)
{
return (Atom *) erts_index_lookup(&erts_atom_table, i);
}
ERTS_GLB_INLINE int erts_is_atom_utf8_bytes(byte *text, size_t len, Eterm term)
{
Atom *a;
if (!is_atom(term))
return 0;
a = atom_tab(atom_val(term));
return (len == (size_t) a->len
&& sys_memcmp((void *) a->name, (void *) text, len) == 0);
}
ERTS_GLB_INLINE int erts_is_atom_str(const char *str, Eterm term, int is_latin1)
{
Atom *a;
int i, len;
const byte* aname;
const byte* s = (const byte*) str;
if (!is_atom(term))
return 0;
a = atom_tab(atom_val(term));
len = a->len;
aname = a->name;
if (is_latin1) {
for (i = 0; i < len; s++) {
if (aname[i] < 0x80) {
if (aname[i] != *s || *s == '\0')
return 0;
i++;
}
else {
if (aname[i] != (0xC0 | (*s >> 6)) ||
aname[i+1] != (0x80 | (*s & 0x3F))) {
return 0;
}
i += 2;
}
}
}
else {
for (i = 0; i < len; i++, s++)
if (aname[i] != *s || *s == '\0')
return 0;
}
return *s == '\0';
}
#endif
typedef enum {
ERTS_ATOM_ENC_7BIT_ASCII,
ERTS_ATOM_ENC_LATIN1,
ERTS_ATOM_ENC_UTF8
} ErtsAtomEncoding;
/*
* Note, ERTS_IS_ATOM_STR() expects the first argument to be a
* 7-bit ASCII string literal.
*/
#define ERTS_IS_ATOM_STR(LSTR, TERM) \
(erts_is_atom_utf8_bytes((byte *) LSTR, sizeof(LSTR) - 1, (TERM)))
#define ERTS_DECL_AM(S) Eterm AM_ ## S = am_atom_put(#S, sizeof(#S) - 1)
#define ERTS_INIT_AM(S) AM_ ## S = am_atom_put(#S, sizeof(#S) - 1)
#define ERTS_MAKE_AM(Str) am_atom_put(Str, sizeof(Str) - 1)
int atom_table_size(void); /* number of elements */
int atom_table_sz(void); /* table size in bytes, excluding stored objects */
Eterm am_atom_put(const char*, Sint); /* ONLY 7-bit ascii! */
Eterm erts_atom_put(const byte *name, Sint len, ErtsAtomEncoding enc, int trunc);
int erts_atom_put_index(const byte *name, Sint len, ErtsAtomEncoding enc, int trunc);
void init_atom_table(void);
void atom_info(fmtfn_t, void *);
void dump_atoms(fmtfn_t, void *);
Uint erts_get_atom_limit(void);
int erts_atom_get(const char* name, Uint len, Eterm* ap, ErtsAtomEncoding enc);
void erts_atom_get_text_space_sizes(Uint *reserved, Uint *used);
#endif
