#pragma once
#include "llama.h"
#include <map>
#include <regex>
#include <string>
#include <vector>
struct llama_vocab;
// grammar element type
enum llama_gretype {
// end of rule definition
LLAMA_GRETYPE_END = 0,
// start of alternate definition for rule
LLAMA_GRETYPE_ALT = 1,
// non-terminal element: reference to rule
LLAMA_GRETYPE_RULE_REF = 2,
// terminal element: character (code point)
LLAMA_GRETYPE_CHAR = 3,
// inverse char(s) ([^a], [^a-b] [^abc])
LLAMA_GRETYPE_CHAR_NOT = 4,
// modifies a preceding LLAMA_GRETYPE_CHAR or LLAMA_GRETYPE_CHAR_ALT to
// be an inclusive range ([a-z])
LLAMA_GRETYPE_CHAR_RNG_UPPER = 5,
// modifies a preceding LLAMA_GRETYPE_CHAR or
// LLAMA_GRETYPE_CHAR_RNG_UPPER to add an alternate char to match ([ab], [a-zA])
LLAMA_GRETYPE_CHAR_ALT = 6,
// any character (.)
LLAMA_GRETYPE_CHAR_ANY = 7,
// terminal element: token (<[token-id]>)
LLAMA_GRETYPE_TOKEN = 8,
// inverse token (!<[token-id]>)
LLAMA_GRETYPE_TOKEN_NOT = 9,
};
typedef struct llama_grammar_element {
enum llama_gretype type;
uint32_t value; // Unicode code point, rule ID, or token ID
} llama_grammar_element;
struct llama_partial_utf8 {
uint32_t value; // bit value so far (unshifted)
int n_remain; // num bytes remaining; -1 indicates invalid sequence
};
struct llama_grammar_candidate {
size_t index;
const uint32_t * code_points;
llama_partial_utf8 partial_utf8;
llama_token id;
};
using llama_grammar_rule = std::vector< llama_grammar_element>;
using llama_grammar_stack = std::vector<const llama_grammar_element *>;
using llama_grammar_rules = std::vector<llama_grammar_rule>;
using llama_grammar_stacks = std::vector<llama_grammar_stack>;
using llama_grammar_candidates = std::vector<llama_grammar_candidate>;
// TODO: remove, needed for tests atm
const llama_grammar_rules & llama_grammar_get_rules (const struct llama_grammar * grammar);
llama_grammar_stacks & llama_grammar_get_stacks( struct llama_grammar * grammar);
// takes a set of possible pushdown stacks on a grammar, which are required to
// be positioned at a character range (see `llama_grammar_advance_stack`), and
// produces the N possible stacks if the given char is accepted at those
// positions
void llama_grammar_accept(struct llama_grammar * grammar, uint32_t chr);
std::vector<llama_grammar_candidate> llama_grammar_reject_candidates_for_stack(
const llama_grammar_rules & rules,
const llama_grammar_stack & stack,
const llama_grammar_candidates & candidates);
struct llama_grammar_parser {
const llama_vocab * vocab;
std::map<std::string, uint32_t> symbol_ids;
llama_grammar_rules rules;
llama_grammar_parser(const struct llama_vocab * vocab = nullptr) : vocab(vocab) {}
llama_grammar_stack c_rules() const;
uint32_t get_symbol_id(const char * src, size_t len);
uint32_t generate_symbol_id(const std::string & base_name);
void add_rule(uint32_t rule_id, const llama_grammar_rule & rule);
const char * parse_alternates(
const char * src,
const std::string & rule_name,
uint32_t rule_id,
bool is_nested);
const char * parse_sequence(
const char * src,
const std::string & rule_name,
llama_grammar_rule & rule,
bool is_nested);
const char * parse_rule(const char * src);
bool parse(const char * src);
void print(FILE * file);
};
struct llama_grammar_trigger_pattern {
std::string pattern;
std::regex regex;
size_t find(const std::string & input) const;
};
struct llama_grammar {
// maintain a list of llama_tokens and their positions in the trigger_buffer
using token_pos = std::pair<llama_token, std::pair<size_t, size_t>>;
// note: allow null vocab for testing (not great)
const llama_vocab * vocab;
const llama_grammar_rules rules; // TODO: shared ptr
llama_grammar_stacks stacks;
// buffer for partially generated UTF-8 sequence from accepted tokens
llama_partial_utf8 partial_utf8;
// lazy grammars wait for trigger words or tokens before constraining the sampling.
// we still have trigger_tokens for non-lazy grammars to force printing of special trigger tokens.
// (useful e.g. for tool_choice=required)
bool lazy = false;
bool awaiting_trigger = false; // Initialized to true for lazy grammars only
std::string trigger_buffer; // Output buffered by lazy grammar. Will be cleared once trigger is found.
std::vector<token_pos> trigger_buffer_positions; // Tokens buffered by lazy grammar. Used to replay when a trigger is found.
std::vector<llama_token> trigger_tokens; // Tokens that trigger a lazy grammar, or tokens to force printing of (even if special).
std::vector<llama_grammar_trigger_pattern>
trigger_patterns; // Regular expressions that trigger a lazy grammar. Must be a full match of the entire generated
// string, and the grammar will be given the string from the first match group onwards.
};
//
// internal API
//
// note: needed for tests (not great)
struct llama_grammar * llama_grammar_init_impl(
const struct llama_vocab * vocab,
const llama_grammar_element ** rules,
size_t n_rules,
size_t start_rule_index);
struct llama_grammar * llama_grammar_init_impl(
const struct llama_vocab * vocab,
const char * grammar_str,
const char * grammar_root,
bool lazy,
const char ** trigger_patterns,
size_t num_trigger_patterns,
const llama_token * trigger_tokens,
size_t num_trigger_tokens);
void llama_grammar_free_impl(struct llama_grammar * grammar);
struct llama_grammar * llama_grammar_clone_impl(const struct llama_grammar & grammar);
// TODO: move the API below as member functions of llama_grammar
void llama_grammar_apply_impl(
const struct llama_grammar & grammar,
llama_token_data_array * cur_p);
void llama_grammar_accept_impl(
struct llama_grammar & grammar,
llama_token token);
void llama_grammar_accept_str(
struct llama_grammar & grammar,
const std::string & piece);
void llama_grammar_accept_token(
struct llama_grammar & grammar,
llama_token token,
const std::string & piece);