From d4b94b5e8388c744a1d879fecb5af957b170c4c1 Mon Sep 17 00:00:00 2001 From: Peter Stephenson Date: Wed, 26 Jul 2017 16:56:23 +0100 Subject: 41464, 41466: With POSIX_BUILTINS, exec only executes sexternal commands. Document the default behaviour and add a test. --- ChangeLog | 5 +++++ Doc/Zsh/builtins.yo | 8 +++++++- Doc/Zsh/options.yo | 4 ++++ Src/exec.c | 14 ++++++++++++-- Test/E01options.ztst | 14 ++++++++++++++ 5 files changed, 42 insertions(+), 3 deletions(-) diff --git a/ChangeLog b/ChangeLog index b885ac05d..b0dcb7e44 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,10 @@ 2017-07-26 Peter Stephenson + * 41464, 41466 (modified): Doc/Zsh/builtins.yo, + Doc/Zsh/options.yo, Src/exec.c, Test/E01options.ztst: + POSIX_BUILTINS stops "exec" finding builtins or shell + functions. Document existing behaviour. + * Jim: 41461: Doc/Zsh/seealso.yo: complete list of zsh manual pages in introduction. diff --git a/Doc/Zsh/builtins.yo b/Doc/Zsh/builtins.yo index 333db1c2c..99b1dd45b 100644 --- a/Doc/Zsh/builtins.yo +++ b/Doc/Zsh/builtins.yo @@ -667,7 +667,10 @@ if there are no var(args) or they contain no commands (i.e. are an empty string or whitespace) the return status is zero. ) item(tt(exec) [ tt(-cl) ] [ tt(-a) var(argv0) ] [ var(command) [ var(arg) ... ] ])( -Replace the current shell with an external var(command) rather than forking. +Replace the current shell with var(command) rather than forking. +If var(command) is a shell builtin command or a shell function, +the shell executes it, then immediately exits. + With tt(-c) clear the environment; with tt(-l) prepend tt(-) to the tt(argv[0]) string of the command executed (to simulate a login shell); with tt(-a) var(argv0) set the tt(argv[0]) string of the command @@ -675,6 +678,9 @@ executed. See ifzman(the section `Precommand Modifiers' in zmanref(zshmisc))\ ifnzman(noderef(Precommand Modifiers)). +If the option tt(POSIX_BUILTINS) is set, var(command) is never +interpreted as a shell builtin command or shell function. + cindex(redirection, current shell's I/O) If var(command) is omitted but any redirections are specified, then the redirections will take effect in the current shell. diff --git a/Doc/Zsh/options.yo b/Doc/Zsh/options.yo index cc6ae2a47..70092d681 100644 --- a/Doc/Zsh/options.yo +++ b/Doc/Zsh/options.yo @@ -2140,6 +2140,10 @@ In addition, various error conditions associated with the above builtins or tt(exec) cause a non-interactive shell to exit and an interactive shell to return to its top-level processing. +Furthermore, functions and shell builtins are not executed after +an tt(exec) prefix; the command to be executed must be an external +command found in the path. + Furthermore, the tt(getopts) builtin behaves in a POSIX-compatible fashion in that the associated variable tt(OPTIND) is not made local to functions. diff --git a/Src/exec.c b/Src/exec.c index 0a9687998..f339dd6d0 100644 --- a/Src/exec.c +++ b/Src/exec.c @@ -2778,6 +2778,12 @@ execcmd_exec(Estate state, Execcmd_params eparams, * Reserved words take precedence over shell functions. */ checked = 1; + } else if (isset(POSIXBUILTINS) && (cflags & BINF_EXEC)) { + /* + * POSIX doesn't allow "exec" to operate on builtins + * or shell functions. + */ + break; } else { if (!(cflags & (BINF_BUILTIN | BINF_COMMAND)) && (hn = shfunctab->getnode(shfunctab, cmdarg))) { @@ -3123,10 +3129,14 @@ execcmd_exec(Estate state, Execcmd_params eparams, * - we have determined there are options which would * require us to use the "command" builtin); or * - we aren't using POSIX and so BINF_COMMAND indicates a zsh - * precommand modifier is being used in place of the builtin + * precommand modifier is being used in place of the + * builtin + * - we are using POSIX and this is an EXEC, so we can't + * execute a builtin or function. */ if (errflag || checked || is_builtin || - (unset(POSIXBUILTINS) && (cflags & BINF_COMMAND))) + (isset(POSIXBUILTINS) ? + (cflags & BINF_EXEC) : (cflags & BINF_COMMAND))) break; cmdarg = (char *) peekfirst(args); diff --git a/Test/E01options.ztst b/Test/E01options.ztst index dac9430cc..f01d83567 100644 --- a/Test/E01options.ztst +++ b/Test/E01options.ztst @@ -831,6 +831,20 @@ >val2 >val2 + print "Contents of file" >cat_arg + ( + cat() { print Function with argument $1 } + print Without + (exec cat cat_arg; print Not reached) + print With + (setopt posixbuiltins; exec cat cat_arg; print Not reached) + ) +0:POSIX_BUILTINS and exec +>Without +>Function with argument cat_arg +>With +>Contents of file + # PRINTEXITVALUE only works if shell input is coming from standard input. # Goodness only knows why. $ZTST_testdir/../Src/zsh -f <<<' -- cgit 1.4.1