From ee553b929c81ae0051abfd54984aa0537f767d89 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 15 Jul 2017 22:51:55 +0200 Subject: [PATCH] hush: fix and_or_and_backgrounding.tests failure function old new delta done_pipe 133 218 +85 Signed-off-by: Denys Vlasenko --- .../and_or_and_backgrounding.right | 0 .../and_or_and_backgrounding.tests | 0 shell/hush.c | 37 ++++++++++++++++++- .../and_or_and_backgrounding.right | 4 ++ .../and_or_and_backgrounding.tests | 31 ++++++++++++++++ 5 files changed, 71 insertions(+), 1 deletion(-) rename shell/{hush_test/hush-bugs => ash_test/ash-parsing}/and_or_and_backgrounding.right (100%) rename shell/{hush_test/hush-bugs => ash_test/ash-parsing}/and_or_and_backgrounding.tests (100%) create mode 100644 shell/hush_test/hush-parsing/and_or_and_backgrounding.right create mode 100755 shell/hush_test/hush-parsing/and_or_and_backgrounding.tests diff --git a/shell/hush_test/hush-bugs/and_or_and_backgrounding.right b/shell/ash_test/ash-parsing/and_or_and_backgrounding.right similarity index 100% rename from shell/hush_test/hush-bugs/and_or_and_backgrounding.right rename to shell/ash_test/ash-parsing/and_or_and_backgrounding.right diff --git a/shell/hush_test/hush-bugs/and_or_and_backgrounding.tests b/shell/ash_test/ash-parsing/and_or_and_backgrounding.tests similarity index 100% rename from shell/hush_test/hush-bugs/and_or_and_backgrounding.tests rename to shell/ash_test/ash-parsing/and_or_and_backgrounding.tests diff --git a/shell/hush.c b/shell/hush.c index b76351fde..2a734f3de 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -3373,12 +3373,47 @@ static void done_pipe(struct parse_context *ctx, pipe_style type) debug_printf_parse("done_pipe entered, followup %d\n", type); /* Close previous command */ not_null = done_command(ctx); - ctx->pipe->followup = type; #if HAS_KEYWORDS ctx->pipe->pi_inverted = ctx->ctx_inverted; ctx->ctx_inverted = 0; ctx->pipe->res_word = ctx->ctx_res_w; #endif + if (type != PIPE_BG || ctx->list_head == ctx->pipe) { + no_conv: + ctx->pipe->followup = type; + } else { + /* Necessary since && and || have more precedence than &: + * "cmd1 && cmd2 &" must spawn both cmds, not only cmd2, + * in a backgrounded subshell. + */ + struct pipe *pi; + struct command *command; + + /* Is this actually the case? */ + pi = ctx->list_head; + while (pi != ctx->pipe) { + if (pi->followup != PIPE_AND && pi->followup != PIPE_OR) + goto no_conv; + pi = pi->next; + } + + debug_printf_parse("BG with more than one pipe, converting to { p1 &&...pN; } &\n"); + pi->followup = PIPE_SEQ; /* close pN _not_ with "&"! */ + pi = xzalloc(sizeof(*pi)); + pi->followup = PIPE_BG; + pi->num_cmds = 1; + pi->cmds = xzalloc(sizeof(pi->cmds[0])); + command = &pi->cmds[0]; + if (CMD_NORMAL != 0) /* "if xzalloc didn't do that already" */ + command->cmd_type = CMD_NORMAL; + command->group = ctx->list_head; +#if !BB_MMU +//TODO: is this correct?! + command->group_as_string = xstrdup(ctx->as_string.data); +#endif + /* Replace all pipes in ctx with one newly created */ + ctx->list_head = ctx->pipe = pi; + } /* Without this check, even just on command line generates * tree of three NOPs (!). Which is harmless but annoying. diff --git a/shell/hush_test/hush-parsing/and_or_and_backgrounding.right b/shell/hush_test/hush-parsing/and_or_and_backgrounding.right new file mode 100644 index 000000000..90ce63e01 --- /dev/null +++ b/shell/hush_test/hush-parsing/and_or_and_backgrounding.right @@ -0,0 +1,4 @@ +First +Second +Third +Done diff --git a/shell/hush_test/hush-parsing/and_or_and_backgrounding.tests b/shell/hush_test/hush-parsing/and_or_and_backgrounding.tests new file mode 100755 index 000000000..05acfb863 --- /dev/null +++ b/shell/hush_test/hush-parsing/and_or_and_backgrounding.tests @@ -0,0 +1,31 @@ +# UNFIXED BUG: hush thinks that ; && || & have the same precedence. +# According to this doc, && || have higher precedence than ; &. +# See example below. +# Precedence of ; is not a problem in practice. Precedence of & is. +# +#http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html +# +#2.9.3 Lists +# +#An AND-OR list is a sequence of one or more pipelines separated by +#the operators "&&" and "||" . +# +#A list is a sequence of one or more AND-OR lists separated by the operators +#';' and '&' and optionally terminated by ';', '&', or . +# +#The operators "&&" and "||" shall have equal precedence and shall be +#evaluated with left associativity. For example, both of the following +#commands write solely bar to standard output: +# +# false && echo foo || echo bar +# true || echo foo && echo bar +# +#A ';' or terminator shall cause the preceding AND-OR list +#to be executed sequentially; an '&' shall cause asynchronous execution +#of the preceding AND-OR list. + +echo First && sleep 0.2 && echo Third & +sleep 0.1 +echo Second +wait +echo Done -- 2.25.1