From 889550b36b057fb8ad5c825c7a17e46fde4ebbf6 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Wed, 14 Jul 2010 19:01:25 +0200 Subject: [PATCH] hush: make pun_pipe loop clearer; fix "cmd | var=`cmd` | cmd" handling function old new delta free_strings - 38 +38 pseudo_exec_argv 161 171 +10 free_pipe 227 205 -22 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/1 up/down: 48/-22) Total: 26 bytes Signed-off-by: Denys Vlasenko --- shell/hush.c | 42 ++++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 16 deletions(-) diff --git a/shell/hush.c b/shell/hush.c index 31ca22a2e..8a467be80 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -3713,11 +3713,17 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save, { char **new_env; - /* Case when we are here: ... | var=val | ... */ - if (!argv[assignment_cnt]) + new_env = expand_assignments(argv, assignment_cnt); + + if (!argv[assignment_cnt]) { + /* Case when we are here: ... | var=val | ... + * (note that we do not exit early, i.e., do not optimize out + * expand_assignments(): think about ... | var=`sleep 1` | ... + */ + free_strings(new_env); _exit(EXIT_SUCCESS); + } - new_env = expand_assignments(argv, assignment_cnt); #if BB_MMU set_vars_and_save_old(new_env); free(new_env); /* optional */ @@ -3727,6 +3733,7 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save, nommu_save->new_env = new_env; nommu_save->old_vars = set_vars_and_save_old(new_env); #endif + if (argv_expanded) { argv = argv_expanded; } else { @@ -4145,8 +4152,9 @@ static int checkjobs_and_fg_shell(struct pipe* fg_pipe) static NOINLINE int run_pipe(struct pipe *pi) { static const char *const null_ptr = NULL; - int i; - int nextin; + + int cmd_no; + int next_infd; struct command *command; char **argv_expanded; char **argv; @@ -4160,7 +4168,7 @@ static NOINLINE int run_pipe(struct pipe *pi) IF_HUSH_JOB(pi->pgrp = -1;) pi->stopped_cmds = 0; - command = &(pi->cmds[0]); + command = &pi->cmds[0]; argv_expanded = NULL; if (pi->num_cmds != 1 @@ -4358,9 +4366,10 @@ static NOINLINE int run_pipe(struct pipe *pi) /* Going to fork a child per each pipe member */ pi->alive_cmds = 0; - nextin = 0; + next_infd = 0; - for (i = 0; i < pi->num_cmds; i++) { + cmd_no = 0; + while (cmd_no < pi->num_cmds) { struct fd_pair pipefds; #if !BB_MMU volatile nommu_save_t nommu_save; @@ -4369,7 +4378,8 @@ static NOINLINE int run_pipe(struct pipe *pi) nommu_save.argv = NULL; nommu_save.argv_from_re_execing = NULL; #endif - command = &(pi->cmds[i]); + command = &pi->cmds[cmd_no]; + cmd_no++; if (command->argv) { debug_printf_exec(": pipe member '%s' '%s'...\n", command->argv[0], command->argv[1]); @@ -4380,7 +4390,7 @@ static NOINLINE int run_pipe(struct pipe *pi) /* pipes are inserted between pairs of commands */ pipefds.rd = 0; pipefds.wr = 1; - if ((i + 1) < pi->num_cmds) + if (cmd_no < pi->num_cmds) xpiped_pair(pipefds); command->pid = BB_MMU ? fork() : vfork(); @@ -4413,7 +4423,7 @@ static NOINLINE int run_pipe(struct pipe *pi) if (open(bb_dev_null, O_RDONLY)) xopen("/", O_RDONLY); } else { - xmove_fd(nextin, 0); + xmove_fd(next_infd, 0); } xmove_fd(pipefds.wr, 1); if (pipefds.rd > 1) @@ -4460,12 +4470,12 @@ static NOINLINE int run_pipe(struct pipe *pi) #endif } - if (i) - close(nextin); - if ((i + 1) < pi->num_cmds) + if (cmd_no > 1) + close(next_infd); + if (cmd_no < pi->num_cmds) close(pipefds.wr); /* Pass read (output) pipe end to next iteration */ - nextin = pipefds.rd; + next_infd = pipefds.rd; } if (!pi->alive_cmds) { @@ -7153,7 +7163,7 @@ int hush_main(int argc, char **argv) #endif case 'n': case 'x': - if (!set_mode('-', opt)) + if (set_mode('-', opt) == 0) /* no error */ break; default: #ifndef BB_VER -- 2.25.1