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The ;& operator allows execution to continue to the next case pattern without re-evaluating the switch expression Signed-off-by: Arav Verma --- src/eval.c | 35 +++++++++++++++++++++++++---------- src/mktokens | 1 + src/parser.c | 14 ++++++++++---- 3 files changed, 36 insertions(+), 14 deletions(-) diff --git a/src/eval.c b/src/eval.c index 0f2a7ba..f9acea5 100644 --- a/src/eval.c +++ b/src/eval.c @@ -451,6 +451,7 @@ evalcase(union node *n, int flags) union node *patp; struct arglist arglist; int status = 0; + int fallthrough = 0; errlinno = lineno = n->ncase.linno; if (funcline) @@ -460,19 +461,33 @@ evalcase(union node *n, int flags) expandarg(n->ncase.expr, &arglist, FNMATCH_IS_ENABLED ? EXP_TILDE : EXP_TILDE | EXP_MBCHAR); for (cp = n->ncase.cases ; cp && evalskip == 0 ; cp = cp->nclist.next) { - for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) { - if (casematch(patp, arglist.list->text)) { - /* Ensure body is non-empty as otherwise - * EV_EXIT may prevent us from setting the - * exit status. - */ - if (evalskip == 0 && cp->nclist.body) { - status = evaltree(cp->nclist.body, - flags); + int matched = 0; + + if (fallthrough) { + matched = 1; + } else { + for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) { + if (casematch(patp, arglist.list->text)) { + matched = 1; + break; } - goto out; } } + if (matched) { + int terminator = cp->type >> 8; + if (evalskip == 0 && cp->nclist.body) { + int eval_flags = flags; + if (terminator == TFALLTHRU) + eval_flags &= ~EV_EXIT; + status = evaltree(cp->nclist.body, eval_flags); + if (terminator != TFALLTHRU) + goto out; + } else if (terminator != TFALLTHRU) + goto out; + + if (terminator == TFALLTHRU) + fallthrough = 1; + } } out: return status; diff --git a/src/mktokens b/src/mktokens index dcef676..b7cd0ff 100644 --- a/src/mktokens +++ b/src/mktokens @@ -51,6 +51,7 @@ TPIPE 0 "|" TLP 0 "(" TRP 1 ")" TENDCASE 1 ";;" +TFALLTHRU 1 ";&" TENDBQUOTE 1 "`" TREDIR 0 redirection TWORD 0 word diff --git a/src/parser.c b/src/parser.c index e44b3c3..ede908f 100644 --- a/src/parser.c +++ b/src/parser.c @@ -463,10 +463,12 @@ next_case: checkkwd = CHKNL | CHKKWD; if ((t = readtoken()) != TESAC) { - if (t != TENDCASE) + if (t != TENDCASE && t != TFALLTHRU) synexpect(TENDCASE); - else + else { + cp->type = NCLIST | (t << 8); goto next_case; + } } } *cpp = NULL; @@ -833,11 +835,15 @@ xxreadtoken(void) RETURN(TOR); pungetc(); RETURN(TPIPE); - case ';': - if (pgetc_eatbnl() == ';') + case ';': { + int nextc = pgetc_eatbnl(); + if (nextc == ';') RETURN(TENDCASE); + else if (nextc == '&') + RETURN(TFALLTHRU); pungetc(); RETURN(TSEMI); + } case '(': RETURN(TLP); case ')': -- 2.47.3