diff options
| -rw-r--r-- | ChangeLog | 8 | ||||
| -rw-r--r-- | Src/exec.c | 145 |
2 files changed, 71 insertions, 82 deletions
diff --git a/ChangeLog b/ChangeLog index f93d3d654..8cbcc80bc 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2018-05-01 Peter Stephenson <p.stephenson@samsung.com> + + * from branch fork_early, c.f. 42702: Src/exec.c: Various changes + to make forking for a command work better. Move the fork even + earlier; add case of non-final pipeline elements; _exit when + forked; remove previous early fork in caller; replace fix for + leaked file descriptor in pipeline handling. + 2018-04-29 Oliver Kiddle <okiddle@yahoo.co.uk> * Matthew Martin: 42730: Completion/Unix/Command/_rmdir, diff --git a/Src/exec.c b/Src/exec.c index 64cf5ae46..08c4ea95a 100644 --- a/Src/exec.c +++ b/Src/exec.c @@ -1878,8 +1878,6 @@ static void execpline2(Estate state, wordcode pcode, int how, int input, int output, int last1) { - pid_t pid; - int pipes[2]; struct execcmd_params eparams; if (breaks || retflag) @@ -1900,65 +1898,21 @@ execpline2(Estate state, wordcode pcode, } if (WC_PIPE_TYPE(pcode) == WC_PIPE_END) { execcmd_analyse(state, &eparams); - execcmd_exec(state, &eparams, input, output, how, last1 ? 1 : 2); + execcmd_exec(state, &eparams, input, output, how, last1 ? 1 : 2, -1); } else { + int pipes[2]; int old_list_pipe = list_pipe; - int subsh_close = -1; - Wordcode next = state->pc + (*state->pc), start_pc; + Wordcode next = state->pc + (*state->pc); - start_pc = ++state->pc; + ++state->pc; execcmd_analyse(state, &eparams); if (mpipe(pipes) < 0) { /* FIXME */ } - /* if we are doing "foo | bar" where foo is a current * - * shell command, do foo in a subshell and do the * - * rest of the pipeline in the current shell. */ - if ((eparams.type >= WC_CURSH || !eparams.args) - && (how & Z_SYNC)) { - int synch[2]; - struct timeval bgtime; - - if (pipe(synch) < 0) { - zerr("pipe failed: %e", errno); - lastval = 1; - errflag |= ERRFLAG_ERROR; - return; - } else if ((pid = zfork(&bgtime)) == -1) { - close(synch[0]); - close(synch[1]); - lastval = 1; - errflag |= ERRFLAG_ERROR; - return; - } else if (pid) { - char dummy, *text; - - text = getjobtext(state->prog, start_pc); - addproc(pid, text, 0, &bgtime); - close(synch[1]); - read_loop(synch[0], &dummy, 1); - close(synch[0]); - } else { - zclose(pipes[0]); - close(synch[0]); - entersubsh(((how & Z_ASYNC) ? ESUB_ASYNC : 0) - | ESUB_PGRP | ESUB_KEEPTRAP); - close(synch[1]); - if (sigtrapped[SIGEXIT]) - { - unsettrap(SIGEXIT); - } - execcmd_exec(state, &eparams, input, pipes[1], how, 1); - _exit(lastval); - } - } else { - /* otherwise just do the pipeline normally. */ - addfilelist(NULL, pipes[0]); - subsh_close = pipes[0]; - execcmd_exec(state, &eparams, input, pipes[1], how, 0); - } + addfilelist(NULL, pipes[0]); + execcmd_exec(state, &eparams, input, pipes[1], how, 0, pipes[0]); zclose(pipes[1]); state->pc = next; @@ -1969,8 +1923,6 @@ execpline2(Estate state, wordcode pcode, execpline2(state, *state->pc++, how, pipes[0], output, last1); list_pipe = old_list_pipe; cmdpop(); - if (subsh_close != pipes[0]) - zclose(pipes[0]); } } @@ -2710,7 +2662,8 @@ static void execcmd_getargs(LinkList preargs, LinkList args, int expand) /**/ static int execcmd_fork(Estate state, int how, int type, Wordcode varspc, - LinkList *filelistp, char *text, int oautocont) + LinkList *filelistp, char *text, int oautocont, + int close_if_forked) { pid_t pid; int synch[2], flags; @@ -2766,6 +2719,7 @@ execcmd_fork(Estate state, int how, int type, Wordcode varspc, *filelistp = jobtab[thisjob].filelist; entersubsh(flags); close(synch[1]); + zclose(close_if_forked); if (sigtrapped[SIGINT] & ZSIG_IGNORED) holdintr(); @@ -2786,7 +2740,7 @@ execcmd_fork(Estate state, int how, int type, Wordcode varspc, /**/ static void execcmd_exec(Estate state, Execcmd_params eparams, - int input, int output, int how, int last1) + int input, int output, int how, int last1, int close_if_forked) { HashNode hn = NULL; LinkList filelist = NULL; @@ -2863,6 +2817,29 @@ execcmd_exec(Estate state, Execcmd_params eparams, pushnode(args, dupstring("fg")); } + if ((how & Z_ASYNC) || output) { + /* + * If running in the background, or not the last command in a + * pipeline, we don't need any of the rest of this function to + * affect the state in the main shell, so fork immediately. + * + * In other cases we may need to process the command line + * a bit further before we make the decision. + */ + text = getjobtext(state->prog, eparams->beg); + switch (execcmd_fork(state, how, type, varspc, &filelist, + text, oautocont, close_if_forked)) { + case -1: + goto fatal; + case 0: + break; + default: + return; + } + last1 = forked = 1; + } else + text = NULL; + /* Check if it's a builtin needing automatic MAGIC_EQUALS_SUBST * * handling. Things like typeset need this. We can't detect the * * command if it contains some tokens (e.g. x=ex; ${x}port), so this * @@ -2871,7 +2848,7 @@ execcmd_exec(Estate state, Execcmd_params eparams, if ((type == WC_SIMPLE || type == WC_TYPESET) && args) { /* * preargs contains args that have been expanded by prefork. - * Running execcmd_getargs() causes the any argument available + * Running execcmd_getargs() causes any argument available * in args to be exanded where necessary and transferred to * preargs. We call execcmd_getargs() every time we need to * analyse an argument not available in preargs, though there is @@ -2918,8 +2895,11 @@ execcmd_exec(Estate state, Execcmd_params eparams, is_builtin = 1; /* autoload the builtin if necessary */ - if (!(hn = resolvebuiltin(cmdarg, hn))) + if (!(hn = resolvebuiltin(cmdarg, hn))) { + if (forked) + _exit(lastval); return; + } if (type != WC_TYPESET) magic_assign = (hn->flags & BINF_MAGICEQUALS); break; @@ -3097,6 +3077,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, zerr("unknown exec flag -%c", *cmdopt); lastval = 1; errflag |= ERRFLAG_ERROR; + if (forked) + _exit(lastval); return; } } @@ -3146,28 +3128,6 @@ execcmd_exec(Estate state, Execcmd_params eparams, esprefork = (magic_assign || (isset(MAGICEQUALSUBST) && type != WC_TYPESET)) ? PREFORK_TYPESET : 0; - if (how & Z_ASYNC) { - /* - * If running in the background, we don't need any of - * the rest of this functino to affect the state in the - * main shell, so fork immediately. - * - * In other cases we may need to process the command line - * a bit further before we make the decision. - */ - text = getjobtext(state->prog, eparams->beg); - switch (execcmd_fork(state, how, type, varspc, &filelist, - text, oautocont)) { - case -1: - goto fatal; - case 0: - break; - default: - return; - } - forked = 1; - } else - text = NULL; if (args) { if (eparams->htok) @@ -3212,6 +3172,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, zerr("redirection with no command"); lastval = 1; errflag |= ERRFLAG_ERROR; + if (forked) + _exit(lastval); return; } else if (!nullcmd || !*nullcmd || opts[SHNULLCMD]) { if (!args) @@ -3230,6 +3192,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, } } else if ((cflags & BINF_PREFIX) && (cflags & BINF_COMMAND)) { lastval = 0; + if (forked) + _exit(lastval); return; } else { /* @@ -3240,6 +3204,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, if (badcshglob == 1) { zerr("no match"); lastval = 1; + if (forked) + _exit(lastval); return; } cmdoutval = use_cmdoutval ? lastval : 0; @@ -3253,12 +3219,16 @@ execcmd_exec(Estate state, Execcmd_params eparams, fputc('\n', xtrerr); fflush(xtrerr); } + if (forked) + _exit(lastval); return; } } else if (isset(RESTRICTED) && (cflags & BINF_EXEC) && do_exec) { zerrnam("exec", "%s: restricted", (char *) getdata(firstnode(args))); lastval = 1; + if (forked) + _exit(lastval); return; } @@ -3293,6 +3263,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, lastval = 1; if (oautocont >= 0) opts[AUTOCONTINUE] = oautocont; + if (forked) + _exit(lastval); return; } break; @@ -3301,8 +3273,11 @@ execcmd_exec(Estate state, Execcmd_params eparams, is_builtin = 1; /* autoload the builtin if necessary */ - if (!(hn = resolvebuiltin(cmdarg, hn))) + if (!(hn = resolvebuiltin(cmdarg, hn))) { + if (forked) + _exit(lastval); return; + } break; } cflags &= ~BINF_BUILTIN & ~BINF_COMMAND; @@ -3317,6 +3292,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, lastval = 1; if (oautocont >= 0) opts[AUTOCONTINUE] = oautocont; + if (forked) + _exit(lastval); return; } @@ -3394,6 +3371,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, lastval = 1; if (oautocont >= 0) opts[AUTOCONTINUE] = oautocont; + if (forked) + _exit(lastval); return; } } @@ -3422,6 +3401,8 @@ execcmd_exec(Estate state, Execcmd_params eparams, lastval = 1; if (oautocont >= 0) opts[AUTOCONTINUE] = oautocont; + if (forked) + _exit(lastval); return; } @@ -3497,7 +3478,7 @@ execcmd_exec(Estate state, Execcmd_params eparams, (!is_cursh && (last1 != 1 || nsigtrapped || havefiles() || fdtable_flocks)))) { switch (execcmd_fork(state, how, type, varspc, &filelist, - text, oautocont)) { + text, oautocont, close_if_forked)) { case -1: goto fatal; case 0: |