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/*
* bpeg.h - Header file for the bpeg parser
*/
#include <ctype.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "utils.h"
const char *usage = (
"Usage:\n"
" bpeg [flags] <pattern> [<input files>...]\n\n"
"Flags:\n"
" -h --help\t print the usage and quit\n"
" -v --verbose\t print verbose debugging info\n"
" -s --slow\t run in slow mode for debugging\n"
" -r --replace <replacement> replace the input pattern with the given replacement\n"
" -g --grammar <grammar file> use the specified file as a grammar\n");
/*
* Pattern matching result object
*/
typedef struct match_s {
// Where the match starts and ends (end is after the last character)
const char *start, *end;
unsigned int is_capture:1, is_replacement:1;
const char *name_or_replacement;
struct match_s *child, *nextsibling;
} match_t;
/*
* BPEG virtual machine opcodes
*/
enum VMOpcode {
VM_EMPTY = 0,
VM_ANYCHAR = 1,
VM_ANYTHING_BUT,
VM_STRING,
VM_RANGE,
VM_NOT,
VM_UPTO_AND,
VM_REPEAT,
VM_BEFORE,
VM_AFTER,
VM_CAPTURE,
VM_OTHERWISE,
VM_CHAIN,
VM_REPLACE,
VM_REF,
};
/*
* A struct reperesenting a BPEG virtual machine operation
*/
typedef struct vm_op_s {
enum VMOpcode op;
unsigned int multiline:1;
const char *start, *end;
// Length of the match, if constant, otherwise -1
ssize_t len;
union {
const char *s;
struct {
char low, high;
} range;
struct {
ssize_t min, max;
struct vm_op_s *sep, *repeat_pat;
} repetitions;
// TODO: use a linked list instead of a binary tree
struct {
struct vm_op_s *first, *second;
} multiple;
struct {
struct vm_op_s *replace_pat;
const char *replacement;
} replace;
struct {
struct vm_op_s *capture_pat;
char *name;
} capture;
struct vm_op_s *pat;
} args;
} vm_op_t;
static inline const char *after_spaces(const char *str);
static match_t *free_match(match_t *m);
static match_t *match(const char *str, vm_op_t *op);
static vm_op_t *compile_bpeg(const char *source, const char *str);
static vm_op_t *load_grammar(const char *grammar);
static vm_op_t *add_def(const char *name, const char *source, vm_op_t *op);
static vm_op_t *load_def(const char *name, const char *source);
static vm_op_t *chain_together(vm_op_t *first, vm_op_t *second);
static vm_op_t *compile_bpeg_string(const char *source, const char *str);
static vm_op_t *expand_chain(const char *source, vm_op_t *first);
static vm_op_t *expand_choices(const char *source, vm_op_t *op);
static void print_match(match_t *m, const char *color);
static void set_range(vm_op_t *op, ssize_t min, ssize_t max, vm_op_t *pat, vm_op_t *sep);
typedef struct {
const char *name;
const char *source;
vm_op_t *op;
} def_t;
static def_t defs[1024] = {{NULL, NULL, NULL}};
size_t ndefs = 0;
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