From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12792 invoked by alias); 2 May 2003 23:35:06 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 12715 invoked from network); 2 May 2003 23:35:02 -0000 Received: from unknown (HELO takamaka.act-europe.fr) (142.179.108.108) by sources.redhat.com with SMTP; 2 May 2003 23:35:02 -0000 Received: by takamaka.act-europe.fr (Postfix, from userid 507) id 79F95D34B8; Fri, 2 May 2003 16:34:58 -0700 (PDT) Date: Fri, 02 May 2003 23:35:00 -0000 From: Joel Brobecker To: gdb-patches@sources.redhat.com Subject: [RFA/RFC] Problem with '!' escaping with zsh/bash/ksh Message-ID: <20030502233458.GP992@gnat.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="Yylu36WmvOXNoKYn" Content-Disposition: inline User-Agent: Mutt/1.4i X-SW-Source: 2003-05/txt/msg00023.txt.bz2 --Yylu36WmvOXNoKYn Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-length: 1361 Hello, the following change introduced a problem when forking inferiors when the path to the executable contains '!' characters. This only occurs with sh-like shells, like zsh/bash/ksh. I have reproduced this on Linux and HP/UX. * fork-inferior.c (fork_inferior): Add '!' to the list of characters that need to be quoted when building a string for the shell. Quote '!' specifically with a backslash, since CSH chokes when trying to evaluate "str!str". Witness: (gdb) run Starting program: /home/brobecke/tmp/GEO_ENV!9.159/foo zsh: no such file or directory: /home/brobecke/tmp/GEO_ENV\!9.159/foo Program exited with code 01. You can't do that without a process to debug. As far as I can tell from the comments in fork_inferior and my own experiments, the bang should be escaped only for C shells. To reflect this, I have made the following change to fork-child.c. 2002-05-02 J. Brobecker * fork-child.c (escape_bang_in_quoted_argument): New function. (fork_inferior): Escape '!' characters in quoted arguments only when needed. Tested on HP/UX, with SHELL set to ZSH. No regression. Also tested by verifying that it does fix the problem without breaking csh. Ok to apply? Some better suggestions, maybe? Thanks, -- Joel --Yylu36WmvOXNoKYn Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="fork-child.c.diff" Content-length: 1979 Index: fork-child.c =================================================================== RCS file: /nile.c/cvs/Dev/gdb/gdb-5.3/gdb/fork-child.c,v retrieving revision 1.2 diff -c -3 -p -r1.2 fork-child.c *** fork-child.c 16 Jan 2003 10:40:02 -0000 1.2 --- fork-child.c 2 May 2003 23:31:34 -0000 *************** breakup_args (char *scratch, char **argv *** 93,98 **** --- 93,121 ---- } + /* When executing a command under the given shell, return non-zero + if the '!' character should be escaped when embedded in a quoted + command-line argument. */ + + static int + escape_bang_in_quoted_argument (const char *shell_file) + { + const int shell_file_len = strlen (shell_file); + + /* Bang should be escaped only in C Shells. For now, simply check + that the shell name ends with 'csh', which covers at least csh + and tcsh. This should be good enough for now. */ + + if (shell_file_len < 3) + return 0; + + if (shell_file[shell_file_len - 3] == 'c' + && shell_file[shell_file_len - 2] == 's' + && shell_file[shell_file_len - 1] == 'h') + return 1; + + return 0; + } /* Start an inferior Unix child process and sets inferior_ptid to its pid. EXEC_FILE is the file to run. *************** fork_inferior (char *exec_file_arg, char *** 176,181 **** --- 199,205 ---- char *p; int need_to_quote; + const int escape_bang = escape_bang_in_quoted_argument (shell_file); strcat (shell_command, "exec "); *************** fork_inferior (char *exec_file_arg, char *** 220,226 **** { if (*p == '\'') strcat (shell_command, "'\\''"); ! else if (*p == '!') strcat (shell_command, "\\!"); else strncat (shell_command, p, 1); --- 244,250 ---- { if (*p == '\'') strcat (shell_command, "'\\''"); ! else if (*p == '!' && escape_bang) strcat (shell_command, "\\!"); else strncat (shell_command, p, 1); --Yylu36WmvOXNoKYn--