From owner-freebsd-bugs Thu Feb 10 13:20:23 2000 Delivered-To: freebsd-bugs@freebsd.org Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [204.216.27.21]) by builder.freebsd.org (Postfix) with ESMTP id 287B34513 for ; Thu, 10 Feb 2000 13:20:19 -0800 (PST) Received: (from gnats@localhost) by freefall.freebsd.org (8.9.3/8.9.2) id NAA69877; Thu, 10 Feb 2000 13:20:02 -0800 (PST) (envelope-from gnats@FreeBSD.org) Date: Thu, 10 Feb 2000 13:20:02 -0800 (PST) Message-Id: <200002102120.NAA69877@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org Cc: From: Shawn Halpenny Subject: [PATCH] Re: bin/16393: /bin/sh doesn't strip comments on shebang line Reply-To: Shawn Halpenny Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org The following reply was made to PR bin/16393; it has been noted by GNATS. From: Shawn Halpenny To: freebsd-gnats-submit@FreeBSD.org, ryand@amazon.com Cc: Subject: [PATCH] Re: bin/16393: /bin/sh doesn't strip comments on shebang line Date: Thu, 10 Feb 2000 16:00:30 -0500 I've run into this, too. The problem seems to have two parts. First, the kernel parses the shebang line into white-space-separated tokens without any regard to the presence of a '#' character (which in the case we're interested in, denotes a comment). The first patch makes the parsing slurp up everthing from the '#' to the end-of-line and store it as a single word. This is necessary so that /bin/sh knows where the comment ends (otherwise (as it does currently), /bin/sh would receive the '#' and any comment-words as separate arguments and not know where the comment ended), because when the interpreter is started, the name of the script is tacked on as the the last argument. Second, /bin/sh will take the first non-option as a file name (according to sh(1)), which means it starts looking for a file named the first word of the comment on the shebang line. So, I modified (see second patch) /bin/sh to ignore any command line words that begin with '#' when searching for a file to interpret. This continues to allow things like: sh -c '# this is a nop' and also preservers the original command line for the interpreter. I'm not sure if this is the best way to fix things, but it appears to be consistent with current behavior and address the problem. Patches below. -- Shawn Halpenny | Maniacal@I Ache, Ohm | "Universal Danger!" +- - - - - - - - - - - - - - - - + - - - - - - - - - - - - - - \ | vi:G3kfM~lxfAPXh~l~2x2FirllpfcxlrifaprmfOX~Xp2hr.lrcelyl2p - - - - - - - -| fU~X~refsPprnlxppri2lxlpr,pFrpprrfaPlpfiprgllxp~3Xlpfndw --- /usr/src/sys/kern/imgact_shell.c~ Wed Feb 9 17:14:09 2000 +++ /usr/src/sys/kern/imgact_shell.c Wed Feb 9 17:14:13 2000 @@ -51,6 +51,7 @@ exec_shell_imgact(imgp) struct image_params *imgp; { + const char *comment = NULL; const char *image_header = imgp->image_header; const char *ihp, *line_endp; char *interp; @@ -112,7 +113,15 @@ * because this is at the front of the string buffer * and the maximum shell command length is tiny. */ - while ((ihp < line_endp) && (*ihp != ' ') && (*ihp != '\t')) { + while ((ihp < line_endp) && + ((*ihp != ' ') && (*ihp != '\t') || comment)) { + + /* Shell comment characters at the start of a token cause + * everything to EOL to be one token. + */ + if (*ihp == '#') + comment = ihp; + *imgp->stringp++ = *ihp++; imgp->stringspace--; } --- /usr/src/bin/sh/options.c~ Thu Feb 10 11:02:38 2000 +++ /usr/src/bin/sh/options.c Thu Feb 10 13:41:10 2000 @@ -108,6 +108,15 @@ optlist[i].val = 0; arg0 = argv[0]; if (sflag == 0 && minusc == NULL) { + /* Skip any arguments that start with shell-comment character + * since it is unlikely the filename of a script given on + * the command line will start with one. + */ + while (*argptr && **argptr == '#') + { + argptr++; + } + commandname = arg0 = *argptr++; setinputfile(commandname, 0); } To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message