diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | Doc/Zsh/redirect.yo | 25 | ||||
| -rw-r--r-- | Src/exec.c | 77 | ||||
| -rw-r--r-- | Test/A04redirect.ztst | 7 |
4 files changed, 104 insertions, 11 deletions
diff --git a/ChangeLog b/ChangeLog index 9c24ed7c4..d81404c24 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2005-04-14 Peter Stephenson <pws@csr.com> + + * 21141: Doc/Zsh/redirect.yo, Src/exec.c, Test/A04redirect.ztst: + make NO_CLOBBER apply to {myfd}>... redirections, improve + some error cases, fix bug that {myfd}>>(...) hung on a builtin. + 2005-04-13 Bart Schaefer <schaefer@zsh.org> * 21064: Test/D03procsubst.ztst: test case for 21049. diff --git a/Doc/Zsh/redirect.yo b/Doc/Zsh/redirect.yo index 3ce4b4369..ba4d17a55 100644 --- a/Doc/Zsh/redirect.yo +++ b/Doc/Zsh/redirect.yo @@ -174,6 +174,27 @@ parameter is readonly. However, it is not an error to read or write a file descriptor using tt(<&$)var(param) or tt(>&$)var(param) if var(param) is readonly. +If the option tt(CLOBBER) is unset, it is an error to open a file +descriptor using a parameter that is already set to an open file descriptor +previously allocated by this mechanism. Unsetting the parameter before +using it for allocating a file descriptor avoids the error. + +Note that this mechanism merely allocates or closes a file descriptor; it +does not perform any redirections from or to it. It is usually convenient +to allocate a file descriptor prior to use as an argument to tt(exec). The +following shows a typical sequence of allocation, use, and closing of a +file descriptor: + +example(integer myfd +exec {myfd}>~/logs/mylogfile.txt +print This is a log message. >&$myfd +exec {myfd}>&-) + +Note that the expansion of the variable in the expression tt(>&$myfd) +occurs at the point the redirection is opened. This is after the expansion +of command arguments and after any redirections to the left on the command +line have been processed. + The `tt(|&)' command separator described in ifzman(em(Simple Commands & Pipelines) in zmanref(zshmisc))\ ifnzman(noderef(Simple Commands & Pipelines)) @@ -230,6 +251,10 @@ example(sort <f{oo,ubar}) is equivalent to `tt(cat foo fubar | sort)'. +Expansion of the redirection argument occurs at the point the redirection +is opened, at the point described above for the expansion of the variable +in tt(>&$myfd). + Note that a pipe is an implicit redirection; thus example(cat bar | sort <foo) diff --git a/Src/exec.c b/Src/exec.c index e3555afd2..1ac3f50fd 100644 --- a/Src/exec.c +++ b/Src/exec.c @@ -1405,6 +1405,41 @@ untokenize(char *s) } } +/* Check that we can use a parameter for allocating a file descriptor. */ + +static int +checkclobberparam(struct redir *f) +{ + struct value vbuf; + Value v; + char *s = f->varid; + int fd; + + if (!s) + return 1; + + if (!(v = getvalue(&vbuf, &s, 0))) + return 1; + + if (v->pm->flags & PM_READONLY) { + zwarn("can't allocate file descriptor to readonly parameter %s", + f->varid, 0); + /* don't flag a system error for this */ + errno = 0; + return 0; + } + + if (!isset(CLOBBER) && (fd = (int)getintvalue(v)) && + fd <= max_zsh_fd && fdtable[fd] == FDT_EXTERNAL) { + zwarn("can't clobber parameter %s containing file descriptor %d", + f->varid, fd); + /* don't flag a system error for this */ + errno = 0; + return 0; + } + return 1; +} + /* Open a file for writing redirection */ /**/ @@ -2239,17 +2274,22 @@ execcmd(Estate state, int input, int output, int how, int last1) /* Do io redirections */ while (redir && nonempty(redir)) { fn = (Redir) ugetnode(redir); + DPUTS(fn->type == REDIR_HEREDOC || fn->type == REDIR_HEREDOCDASH, "BUG: unexpanded here document"); if (fn->type == REDIR_INPIPE) { - if (fn->fd2 == -1) { + if (!checkclobberparam(fn) || fn->fd2 == -1) { + if (fn->fd2 != -1) + zclose(fn->fd2); closemnodes(mfds); fixfds(save); execerr(); } addfd(forked, save, mfds, fn->fd1, fn->fd2, 0, fn->varid); } else if (fn->type == REDIR_OUTPIPE) { - if (fn->fd2 == -1) { + if (!checkclobberparam(fn) || fn->fd2 == -1) { + if (fn->fd2 != -1) + zclose(fn->fd2); closemnodes(mfds); fixfds(save); execerr(); @@ -2271,11 +2311,14 @@ execcmd(Estate state, int input, int output, int how, int last1) continue; switch(fn->type) { case REDIR_HERESTR: - fil = getherestr(fn); + if (!checkclobberparam(fn)) + fil = -1; + else + fil = getherestr(fn); if (fil == -1) { closemnodes(mfds); fixfds(save); - if (errno != EINTR) + if (errno && errno != EINTR) zwarn("%e", NULL, errno); execerr(); } @@ -2283,7 +2326,9 @@ execcmd(Estate state, int input, int output, int how, int last1) break; case REDIR_READ: case REDIR_READWRITE: - if (fn->type == REDIR_READ) + if (!checkclobberparam(fn)) + fil = -1; + else if (fn->type == REDIR_READ) fil = open(unmeta(fn->name), O_RDONLY | O_NOCTTY); else fil = open(unmeta(fn->name), @@ -2335,7 +2380,9 @@ execcmd(Estate state, int input, int output, int how, int last1) case REDIR_MERGEOUT: if (fn->fd2 < 10) closemn(mfds, fn->fd2); - if (fn->fd2 > 9 && + if (!checkclobberparam(fn)) + fil = -1; + else if (fn->fd2 > 9 && ((fdtable[fn->fd2] != FDT_UNUSED && fdtable[fn->fd2] != FDT_EXTERNAL) || fn->fd2 == coprocin || @@ -2355,14 +2402,18 @@ execcmd(Estate state, int input, int output, int how, int last1) fixfds(save); if (fn->fd2 != -2) sprintf(fdstr, "%d", fn->fd2); - zwarn("%s: %e", fn->fd2 == -2 ? "coprocess" : fdstr, errno); + if (errno) + zwarn("%s: %e", fn->fd2 == -2 ? "coprocess" : fdstr, + errno); execerr(); } addfd(forked, save, mfds, fn->fd1, fil, fn->type == REDIR_MERGEOUT, fn->varid); break; default: - if (IS_APPEND_REDIR(fn->type)) + if (!checkclobberparam(fn)) + fil = -1; + else if (IS_APPEND_REDIR(fn->type)) fil = open(unmeta(fn->name), (unset(CLOBBER) && !IS_CLOBBER_REDIR(fn->type)) ? O_WRONLY | O_APPEND | O_NOCTTY : @@ -2378,7 +2429,7 @@ execcmd(Estate state, int input, int output, int how, int last1) close(fil); closemnodes(mfds); fixfds(save); - if (errno != EINTR) + if (errno && errno != EINTR) zwarn("%e: %s", fn->name, errno); execerr(); } @@ -2387,7 +2438,10 @@ execcmd(Estate state, int input, int output, int how, int last1) addfd(forked, save, mfds, 2, dfil, 1, NULL); break; } + /* May be error in addfd due to setting parameter. */ if (errflag) { + closemnodes(mfds); + fixfds(save); execerr(); } } @@ -3234,6 +3288,9 @@ mpipe(int *pp) * If the second argument is 1, this is part of * an "exec < <(...)" or "exec > >(...)" and we shouldn't * wait for the job to finish before continuing. + * Likewise, we shouldn't wait if we are opening the file + * descriptor using the {fd}>>(...) notation since it stays + * valid for subsequent commands. */ /**/ @@ -3249,7 +3306,7 @@ spawnpipes(LinkList l, int nullexec) f = (Redir) getdata(n); if (f->type == REDIR_OUTPIPE || f->type == REDIR_INPIPE) { str = f->name; - f->fd2 = getpipe(str, nullexec); + f->fd2 = getpipe(str, nullexec || f->varid); } } } diff --git a/Test/A04redirect.ztst b/Test/A04redirect.ztst index 4ed65e189..66326008f 100644 --- a/Test/A04redirect.ztst +++ b/Test/A04redirect.ztst @@ -248,6 +248,11 @@ >Examining contents of logfile... >This is my logfile. + setopt noclobber + exec {myfd}>logfile2 +1q:NO_CLOBBER prevents overwriting parameter with allocated fd +?(eval):2: can't clobber parameter myfd containing file descriptor $myfd + exec {myfd}>&- print This message should disappear >&$myfd 1q:Closing file descriptor using brace syntax @@ -256,7 +261,7 @@ typeset -r myfd echo This should not appear {myfd}>nologfile 1:Error opening file descriptor using readonly variable -?(eval):2: read-only variable: myfd +?(eval):2: can't allocate file descriptor to readonly parameter myfd typeset +r myfd exec {myfd}>newlogfile |