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hush: fix "... pattern) cmd;; esac" case

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This commit is contained in:
Denis Vlasenko 2008-07-14 08:26:47 +00:00
parent 395ae45216
commit 757361f9f5
2 changed files with 27 additions and 3 deletions
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6
shell/hush.c
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@ -2986,7 +2986,9 @@ static int done_word(o_string *word, struct p_context *ctx)
}
#if HAS_KEYWORDS
#if ENABLE_HUSH_CASE
if (ctx->ctx_dsemicolon) {
if (ctx->ctx_dsemicolon
&& strcmp(word->data, "esac") != 0 /* not "... pattern) cmd;; esac" */
) {
/* already done when ctx_dsemicolon was set to 1: */
/* ctx->ctx_res_w = RES_MATCH; */
ctx->ctx_dsemicolon = 0;
@ -3112,7 +3114,7 @@ static void done_pipe(struct p_context *ctx, pipe_style type)
if (not_null IF_HAS_KEYWORDS(|| ctx->ctx_res_w != RES_NONE)) {
struct pipe *new_p;
debug_printf_parse("done_pipe: adding new pipe: "
" not_null:%d ctx->ctx_res_w:%d\n",
"not_null:%d ctx->ctx_res_w:%d\n",
not_null, ctx->ctx_res_w);
new_p = new_pipe();
ctx->pipe->next = new_p;

24
shell/hush_doc.txt
View File

@ -72,10 +72,32 @@ Dummy trailing pipes with no commands are artifacts of imperfect
parsing algorithm - done_pipe() appends new pipe struct beforehand
and last one ends up empty and unused.
"for" and "case" statements (ab)use progs[] to keep their data
instead of argv vector progs[] usually do. "for" keyword is forcing
pipe termination after first word, which makes hush see
"for v in..." as "for v; in...". "case" keyword does the same.
Other judiciuosly placed hacks make hush see
"case word in a) cmd1;; b) cmd2;; esac" as if it was
"case word; match a; cmd; match b; cmd2; esac"
("match" is a fictitious keyword here):
"case word in a) cmd1;; b) cmd2; esac" -
pipe 0 res_word=NONE followup=1 SEQ
prog 0 group {}:
pipe 0 res_word=CASE followup=SEQ prog[0] 'word'
pipe 1 res_word=MATCH followup=SEQ prog[0] 'a'
pipe 2 res_word=CASEI followup=SEQ prog[0] 'cmd1'
pipe 3 res_word=MATCH followup=SEQ prog[0] 'b'
pipe 4 res_word=CASEI followup=SEQ prog[0] 'cmd2'
pipe 5 res_word=CASEI followup=SEQ prog[0] 'cmd3'
pipe 6 res_word=ESAC followup=SEQ
pipe 7 res_word=NONE followup=(null)
pipe 1 res_word=NONE followup=1 SEQ
2008-01
This is how hush runs commands:
Command execution
/* callsite: process_command_subs */
generate_stream_from_list(struct pipe *head) - handles `cmds`