From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2209) id 379F63885537; Wed, 26 Oct 2022 21:17:10 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 379F63885537 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1666819030; bh=LUWwGgxhLfhZA3tkMNxGdxdLUZuR/0EXECR8uGuJcSo=; h=From:To:Subject:Date:From; b=soPwlV6siIz2NwoRNOGJnbVAGstR72cAgipXs4VclBH+FA2/2nPzlfmTumR26OCou /e/j+g1JKWBKxiy/vd3hi39ciJUk9Yi4BebU5K/4g59Xb446W7nXqmZBpQjHXAqUCM vevhPWEtJuuwcTxDBhgnyys5trJcztWP9uEr/jpk= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: David Malcolm To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-3514] analyzer: add sm-fd.dot X-Act-Checkin: gcc X-Git-Author: David Malcolm X-Git-Refname: refs/heads/master X-Git-Oldrev: f7d28818179247685f3c101f9f2f16366f56309b X-Git-Newrev: 593254ae03a6c0db5946e44b2cfd90dbfc707a17 Message-Id: <20221026211710.379F63885537@sourceware.org> Date: Wed, 26 Oct 2022 21:17:10 +0000 (GMT) List-Id: https://gcc.gnu.org/g:593254ae03a6c0db5946e44b2cfd90dbfc707a17 commit r13-3514-g593254ae03a6c0db5946e44b2cfd90dbfc707a17 Author: David Malcolm Date: Wed Oct 26 16:44:23 2022 -0400 analyzer: add sm-fd.dot Add a .dot file to document the file descriptor state machine. gcc/analyzer/ChangeLog: * sm-fd.dot: New file. Signed-off-by: David Malcolm Diff: --- gcc/analyzer/sm-fd.dot | 109 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) diff --git a/gcc/analyzer/sm-fd.dot b/gcc/analyzer/sm-fd.dot new file mode 100644 index 00000000000..175daae44ae --- /dev/null +++ b/gcc/analyzer/sm-fd.dot @@ -0,0 +1,109 @@ +/* An overview of the state machine from sm-fd.cc. + Copyright (C) 2022 Free Software Foundation, Inc. + Contributed by David Malcolm . + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it +under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +. */ + +/* Keep this in-sync with sm-dot.cc */ + +digraph "fd" { + + /* STATES. */ + + /* Start state. */ + start; + + /* States representing a file descriptor that hasn't yet been + checked for validity after opening, for three different + access modes. */ + unchecked_read_write; + unchecked_read_only; + unchecked_write_only; + + /* States for representing a file descriptor that is known to be valid (>= + 0), for three different access modes. */ + valid_read_write; + valid_read_only; + valid_write_only; + + /* State for a file descriptor that is known to be invalid (< 0). */ + invalid; + + /* State for a file descriptor that has been closed. */ + closed; + + /* State for a file descriptor that we do not want to track anymore . */ + stop; + + /* TRANSITIONS. */ + + /* On "open". */ + start -> unchecked_read_only [label="on 'X = open(..., O_RDONLY);'"]; + start -> unchecked_write_only [label="on 'X = open(..., O_WRONLY);'"]; + start -> unchecked_read_write [label="on 'X = open(..., ...);'"]; + + /* On "creat". */ + start -> unchecked_write_only [label="on 'X = create(...);'"]; + + /* On "close". */ + start -> closed [label="on 'close(X);'"]; + unchecked_read_write -> closed [label="on 'close(X);'"]; + unchecked_read_only -> closed [label="on 'close(X);'"]; + unchecked_write_only -> closed [label="on 'close(X);'"]; + valid_read_write -> closed [label="on 'close(X);'"]; + valid_read_only -> closed [label="on 'close(X);'"]; + valid_write_only -> closed [label="on 'close(X);'"]; + constant_fd -> closed [label="on 'close(X);'"]; + closed -> stop [label="on 'close(X);':\nWarn('double close')"]; + + /* On "read". */ + closed -> closed [label="on 'read(X);':\nWarn('use after close')"]; + unchecked_read_write -> unchecked_read_write [label="on 'read(X);:\nWarn('use without check')'"]; + unchecked_read_only -> unchecked_read_only [label="on 'read(X);:\nWarn('use without check')'"]; + unchecked_write_only -> unchecked_write_only [label="on 'read(X);:\nWarn('use without check')'"]; + valid_write_only -> valid_write_only [label="on 'read(X);:\nWarn('access mode mismatch')'"]; + + /* On "write". */ + closed -> closed [label="on 'write(X);':\nWarn('use after close')"]; + unchecked_read_write -> unchecked_read_write [label="on 'write(X);:\nWarn('use without check')'"]; + unchecked_read_only -> unchecked_read_only [label="on 'write(X);:\nWarn('use without check')'"]; + unchecked_write_only -> unchecked_write_only [label="on 'write(X);:\nWarn('use without check')'"]; + valid_read_only -> valid_read_only [label="on 'write(X);:\nWarn('access mode mismatch')'"]; + + /* On "dup". */ + closed -> closed [label="on 'dup(X);':\nWarn('use after close')"]; + /* plus stuff for the new fd. */ + + /* On "pipe". */ + start -> valid_read_write [label="when 'pipe()' succeeds"]; + + /* on_condition. */ + unchecked_read_write -> valid_read_write [label="on 'X >= 0'"]; + unchecked_read_only -> valid_read_only [label="on 'X >= 0'"]; + unchecked_write_only -> valid_write_only [label="on 'X >= 0'"]; + unchecked_read_write -> invalid [label="on 'X < 0'"]; + unchecked_read_only -> invalid [label="on 'X < 0'"]; + unchecked_write_only -> invalid [label="on 'X < 0'"]; + + /* Leaks. */ + unchecked_read_write -> stop [label="on leak:\nWarn('leak')"]; + unchecked_read_only -> stop [label="on leak:\nWarn('leak')"]; + unchecked_write_only -> stop [label="on leak:\nWarn('leak')"]; + valid_read_write -> stop [label="on leak:\nWarn('leak')"]; + valid_read_only -> stop [label="on leak:\nWarn('leak')"]; + valid_write_only -> stop [label="on leak:\nWarn('leak')"]; +}