From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vultr.musolino.id.au ([45.76.123.158]) by ewsd; Mon Aug 3 09:46:06 EDT 2020 Received: from 58.170.204.252 ([58.170.204.252]) by vultr; Mon Aug 3 23:45:30 EST 2020 Message-ID: <2D6A76C7C50986C7669481E6D1A7D780@musolino.id.au> From: Alex Musolino Date: Mon, 3 Aug 2020 23:15:28 +0930 To: 9front@9front.org Subject: Re: [9front] Patch to fix test(1) expression parsing In-Reply-To: <8155F03D042A477BCB2881C5C2FD20E1@musolino.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit List-ID: <9front.9front.org> List-Help: X-Glyph: ➈ X-Bullshit: high-performance self-signing-based realtime-java shader-scale locator > Yeah, I did this in an updated patch I sent in a subsequent email. It turns out that the second patch is rubbish too. This one should be better. I've further amended the man page to also drop the description of an unimplemented feature. I'm using a test suite [1] derived from something joe9 posted in #cat-v which, in turn, was based on something from OpenBSD. [1] http://musolino.id.au/up/2020/08/03/test.testsuite.rc diff -r aa3d84fc81f6 sys/man/1/test --- a/sys/man/1/test Sun Aug 02 18:30:01 2020 +0930 +++ b/sys/man/1/test Mon Aug 03 23:11:04 2020 +0930 @@ -100,11 +100,6 @@ .BR -le may be used in place of .BR -eq . -The (nonstandard) construct -.BI -l " string\f1, -meaning the length of -.IR string , -may be used in place of an integer. .TP .IB a " -nt " b True if file @@ -209,10 +204,3 @@ .B /sys/src/cmd/test.c .SH "SEE ALSO" .IR rc (1) -.SH BUGS -Won't complain about extraneous arguments -since there may be arguments left unprocessed by -short-circuit evaluation of -.B -a -or -.BR -o . diff -r aa3d84fc81f6 sys/src/cmd/test.c --- a/sys/src/cmd/test.c Sun Aug 02 18:30:01 2020 +0930 +++ b/sys/src/cmd/test.c Mon Aug 03 23:11:04 2020 +0930 @@ -30,7 +30,7 @@ int isnewerthan(char *, char *); int hasmode(char *, ulong); int tio(char *, int); -int e(void), e1(void), e2(void), e3(void); +int e(int), e1(int), e2(int), e3(int); char *nxtarg(int); void @@ -47,12 +47,8 @@ argv[ac] = 0; if (ac<=1) exits("usage"); - r = e(); - /* - * nice idea but short-circuit -o and -a operators may have - * not consumed their right-hand sides. - */ - if(0 && (c = nxtarg(1)) != nil) + r = e(1); + if((c = nxtarg(1)) != nil) synbad("unexpected operator/operand: ", c); exits(r?0:"false"); } @@ -81,78 +77,128 @@ } int -e(void) +e(int eval) { + char *op; int p1; - p1 = e1(); - if (EQ(nxtarg(1), "-o")) - return(p1 || e()); - ap--; - return(p1); + p1 = e1(eval); + for(;;){ + op = nxtarg(1); + if(op == nil) + break; + if(!EQ(op, "-o")){ + ap--; + return p1; + } + if(!p1 && eval) + p1 |= e1(1); + else + e1(0); + } + return p1; } int -e1(void) +e1(int eval) { + char *op; int p1; - p1 = e2(); - if (EQ(nxtarg(1), "-a")) - return (p1 && e1()); - ap--; - return(p1); + p1 = e2(eval); + for(;;){ + op = nxtarg(1); + if(op == nil) + break; + if(!EQ(op, "-a")){ + ap--; + return p1; + } + if(p1 && eval) + p1 &= e2(1); + else + e2(0); + } + return p1; } int -e2(void) +e2(int eval) { - if (EQ(nxtarg(0), "!")) - return(!e2()); + char *op; + int p1; + + p1 = 0; + for(;;){ + op = nxtarg(1); + if(op == nil) + return p1 ^ 1; + if(!EQ(op, "!")) + break; + p1 ^= 1; + } ap--; - return(e3()); + return(p1^e3(eval)); } int -e3(void) +e3(int eval) { int p1, int1, int2; - char *a, *p2; + char *a, *b, *p2; a = nxtarg(0); if(EQ(a, "(")) { - p1 = e(); + p1 = e(eval); if(!EQ(nxtarg(0), ")")) synbad(") expected",""); return(p1); } - if(EQ(a, "-A")) - return(hasmode(nxtarg(0), DMAPPEND)); + if(EQ(a, "-A")){ + b = nxtarg(0); + return(eval && hasmode(b, DMAPPEND)); + } - if(EQ(a, "-L")) - return(hasmode(nxtarg(0), DMEXCL)); + if(EQ(a, "-L")){ + b = nxtarg(0); + return(eval && hasmode(b, DMEXCL)); + } - if(EQ(a, "-T")) - return(hasmode(nxtarg(0), DMTMP)); + if(EQ(a, "-T")){ + b = nxtarg(0); + return(eval && hasmode(b, DMTMP)); + } - if(EQ(a, "-f")) - return(isreg(nxtarg(0))); + if(EQ(a, "-f")){ + b = nxtarg(0); + return(eval && isreg(b)); + } - if(EQ(a, "-d")) - return(isdir(nxtarg(0))); + if(EQ(a, "-d")){ + b = nxtarg(0); + return(eval && isdir(b)); + } - if(EQ(a, "-r")) - return(tio(nxtarg(0), AREAD)); + if(EQ(a, "-r")){ + b = nxtarg(0); + return(eval && tio(b, AREAD)); + } - if(EQ(a, "-w")) - return(tio(nxtarg(0), AWRITE)); + if(EQ(a, "-w")){ + b = nxtarg(0); + return(eval && tio(b, AWRITE)); + } - if(EQ(a, "-x")) - return(tio(nxtarg(0), AEXEC)); + if(EQ(a, "-x")){ + b = nxtarg(0); + return(eval && tio(b, AEXEC)); + } - if(EQ(a, "-e")) - return(tio(nxtarg(0), AEXIST)); + if(EQ(a, "-e")){ + b = nxtarg(0); + return(eval && tio(b, AEXIST)); + } if(EQ(a, "-c")) return(0); @@ -166,14 +212,16 @@ if(EQ(a, "-g")) return(0); - if(EQ(a, "-s")) - return(fsizep(nxtarg(0))); + if(EQ(a, "-s")){ + b = nxtarg(0); + return(eval && fsizep(b)); + } if(EQ(a, "-t")) if(ap>=ac) - return(isatty(1)); + return(eval && isatty(1)); else if(nxtintarg(&int1)) - return(isatty(int1)); + return(eval && isatty(int1)); else synbad("not a valid file descriptor number ", ""); @@ -191,35 +239,40 @@ if(EQ(p2, "!=")) return(!EQ(nxtarg(0), a)); - if(EQ(p2, "-older")) - return(isolder(nxtarg(0), a)); - - if(EQ(p2, "-ot")) - return(isolderthan(nxtarg(0), a)); - - if(EQ(p2, "-nt")) - return(isnewerthan(nxtarg(0), a)); - - if(!isint(a, &int1)) - synbad("unexpected operator/operand: ", p2); - - if(nxtintarg(&int2)){ - if(EQ(p2, "-eq")) - return(int1==int2); - if(EQ(p2, "-ne")) - return(int1!=int2); - if(EQ(p2, "-gt")) - return(int1>int2); - if(EQ(p2, "-lt")) - return(int1=int2); - if(EQ(p2, "-le")) - return(int1<=int2); + if(EQ(p2, "-older")){ + b = nxtarg(0); + return(eval && isolder(b, a)); } - synbad("unknown operator ",p2); - return 0; /* to shut ken up */ + if(EQ(p2, "-ot")){ + b = nxtarg(0); + return(eval && isolderthan(b, a)); + } + + if(EQ(p2, "-nt")){ + b = nxtarg(0); + return(eval && isnewerthan(b, a)); + } + + if(isint(a, &int1)){ + if(nxtintarg(&int2)){ + if(EQ(p2, "-eq")) + return(int1==int2); + if(EQ(p2, "-ne")) + return(int1!=int2); + if(EQ(p2, "-gt")) + return(int1>int2); + if(EQ(p2, "-lt")) + return(int1=int2); + if(EQ(p2, "-le")) + return(int1<=int2); + ap--; + } + } + ap--; + return !EQ(a, ""); } int