tmc-parse.c

#include <ctype.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#include <str.h>

#include <tmc.h>
#include <tmc-parse.h>

enum id {
	tok_null,
	tok_eof,
	tok_err,
	tok_colon,
	tok_ignore,
	tok_invert,
	tok_left,
	tok_name,
	tok_pipe,
	tok_right,
	tok_semi,
};

enum context {
	st_error,
	st_name,
	st_write,
	st_shift,
	st_chld,
};

struct token {
	enum id type;
	uint8_t *value;
	size_t length;
};

/* lex - store the next token from buffer in token */
static size_t lex(struct token *token, uint8_t *buffer, size_t length);

size_t
lex(struct token *token, uint8_t *buffer, size_t length)
{
	static enum id table[256] = {
		[':'] = tok_colon,
		['|'] = tok_pipe,
		[';'] = tok_semi,
		['>'] = tok_left,
		['<'] = tok_right,
		['^'] = tok_invert,
		['_'] = tok_ignore,
	};
	size_t extent;

	*token = (struct token){0};

	extent = eat_spaces(buffer, length);

	if (extent == length) {
		token->type = tok_eof;
		return extent;
	}

	buffer += extent, length -= extent;

	token->value = buffer;

	token->type = table[buffer[extent]];
	if (token->type) {
		token->length = 1;
		return extent + 1;
	}

	token->type = tok_name;
	extent += token->length = eat_ident(buffer, length);
	return extent;
}
	
void
parse(struct parse *result, uint8_t *buffer, size_t length)
{
	struct token token[1];
	size_t offset=0;

	*result = (struct parse){0};

	if (!length) return;

	while (!result->error) {
		offset += lex(token, buffer, length);
		if (token->type == tok_eof) return;
	}

	return;
}

void
parse_error(struct parse *result, char *msg)
{
	return;
}