view rust/hg-core/src/re2/rust_re2.cpp @ 44420:6329ce04c69f

rust-nodemap: accounting for dead blocks By the very append-only nature of the `NodeTree`, inserting new blocks has the effect of making some of the older ones useless as they become unreachable. Therefore some automatic housekeeping will need to be provided. This is standard procedure in the word of databases, under names such as "repack" or "vacuum". The new `masked_readonly_blocks()` will provide callers with useful information to decide if the nodetree is ripe for repacking, but all the `NodeTree` can provide is how many blocks have been masked in the currently mutable part. Analysing the readonly part would be way too long to do it for each transaction and defeat the whole purpose of nodemap persistence. Serializing callers (from the Python layer) will get this figure before each extraction and maintain an aggregate counter of unreachable blocks separately. Note: at this point, the most efficient repacking is just to restart afresh with a full rescan. Differential Revision: https://phab.mercurial-scm.org/D8097
author Georges Racinet <georges.racinet@octobus.net>
date Tue, 18 Feb 2020 19:11:17 +0100
parents d8d4fa9a7f18
children
line wrap: on
line source

/*
rust_re2.cpp

C ABI export of Re2's C++ interface for Rust FFI.

Copyright 2020 Valentin Gatien-Baron

This software may be used and distributed according to the terms of the
GNU General Public License version 2 or any later version.
*/

#include <re2/re2.h>
using namespace re2;

extern "C" {
	RE2* rust_re2_create(const char* data, size_t len) {
		RE2::Options o;
		o.set_encoding(RE2::Options::Encoding::EncodingLatin1);
		o.set_log_errors(false);
		o.set_max_mem(50000000);

		return new RE2(StringPiece(data, len), o);
	}

	void rust_re2_destroy(RE2* re) {
		delete re;
	}

	bool rust_re2_ok(RE2* re) {
		return re->ok();
	}

	void rust_re2_error(RE2* re, const char** outdata, size_t* outlen) {
		const std::string& e = re->error();
		*outdata = e.data();
		*outlen = e.length();
	}

	bool rust_re2_match(RE2* re, char* data, size_t len, int ianchor) {
		const StringPiece sp = StringPiece(data, len);

		RE2::Anchor anchor =
			ianchor == 0 ? RE2::Anchor::UNANCHORED :
			(ianchor == 1 ? RE2::Anchor::ANCHOR_START :
			 RE2::Anchor::ANCHOR_BOTH);

		return re->Match(sp, 0, len, anchor, NULL, 0);
	}
}