From 7a6cc97f3c2fe8c01ac71e39514a73c0674b9061 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Miha=20Rihtar=C5=A1i=C4=8D?= Date: Tue, 19 Oct 2021 18:41:13 +0200 Subject: [PATCH] Avoid excessive specbinding in all-completions * src/minibuf.c (match_regexps): (Ftry_completion): (Fall_completions): (Ftest_completion): Use fast_string_match_internal to match against regexps in completion-regexp-list without having to bind case-fold-search. --- src/minibuf.c | 105 +++++++++++++++----------------------------------- 1 file changed, 32 insertions(+), 73 deletions(-) diff --git a/src/minibuf.c b/src/minibuf.c index 0dc340e9670..6c0cd358c50 100644 --- a/src/minibuf.c +++ b/src/minibuf.c @@ -1545,6 +1545,27 @@ minibuf_conform_representation (Lisp_Object string, Lisp_Object basis) return Fstring_make_multibyte (string); } +static bool +match_regexps (Lisp_Object string, Lisp_Object regexps, + bool ignore_case) +{ + ptrdiff_t val; + for (; CONSP (regexps); regexps = XCDR (regexps)) + { + CHECK_STRING (XCAR (regexps)); + + val = fast_string_match_internal + (XCAR (regexps), string, + (ignore_case ? BVAR (current_buffer, case_canon_table) : Qnil)); + + if (val == -2) + error ("Stack overflow in regexp matcher"); + if (val < 0) + return false; + } + return true; +} + DEFUN ("try-completion", Ftry_completion, Stry_completion, 2, 3, 0, doc: /* Return common substring of all completions of STRING in COLLECTION. Test each possible completion specified by COLLECTION @@ -1578,6 +1599,7 @@ Additionally to this predicate, `completion-regexp-list' is used to further constrain the set of candidates. */) (Lisp_Object string, Lisp_Object collection, Lisp_Object predicate) { + Lisp_Object bestmatch, tail, elt, eltstring; /* Size in bytes of BESTMATCH. */ ptrdiff_t bestmatchsize = 0; @@ -1591,7 +1613,6 @@ is used to further constrain the set of candidates. */) ? list_table : function_table)); ptrdiff_t idx = 0, obsize = 0; int matchcount = 0; - ptrdiff_t bindcount = -1; Lisp_Object bucket, zero, end, tem; CHECK_STRING (string); @@ -1670,27 +1691,10 @@ is used to further constrain the set of candidates. */) completion_ignore_case ? Qt : Qnil), EQ (Qt, tem))) { - /* Yes. */ - Lisp_Object regexps; - /* Ignore this element if it fails to match all the regexps. */ - { - for (regexps = Vcompletion_regexp_list; CONSP (regexps); - regexps = XCDR (regexps)) - { - if (bindcount < 0) - { - bindcount = SPECPDL_INDEX (); - specbind (Qcase_fold_search, - completion_ignore_case ? Qt : Qnil); - } - tem = Fstring_match (XCAR (regexps), eltstring, zero, Qnil); - if (NILP (tem)) - break; - } - if (CONSP (regexps)) - continue; - } + if (!match_regexps (eltstring, Vcompletion_regexp_list, + completion_ignore_case)) + continue; /* Ignore this element if there is a predicate and the predicate doesn't like it. */ @@ -1701,11 +1705,6 @@ is used to further constrain the set of candidates. */) tem = Fcommandp (elt, Qnil); else { - if (bindcount >= 0) - { - unbind_to (bindcount, Qnil); - bindcount = -1; - } tem = (type == hash_table ? call2 (predicate, elt, HASH_VALUE (XHASH_TABLE (collection), @@ -1787,9 +1786,6 @@ is used to further constrain the set of candidates. */) } } - if (bindcount >= 0) - unbind_to (bindcount, Qnil); - if (NILP (bestmatch)) return Qnil; /* No completions found. */ /* If we are ignoring case, and there is no exact match, @@ -1849,7 +1845,6 @@ with a space are ignored unless STRING itself starts with a space. */) : VECTORP (collection) ? 2 : NILP (collection) || (CONSP (collection) && !FUNCTIONP (collection)); ptrdiff_t idx = 0, obsize = 0; - ptrdiff_t bindcount = -1; Lisp_Object bucket, tem, zero; CHECK_STRING (string); @@ -1934,27 +1929,10 @@ with a space are ignored unless STRING itself starts with a space. */) completion_ignore_case ? Qt : Qnil), EQ (Qt, tem))) { - /* Yes. */ - Lisp_Object regexps; - /* Ignore this element if it fails to match all the regexps. */ - { - for (regexps = Vcompletion_regexp_list; CONSP (regexps); - regexps = XCDR (regexps)) - { - if (bindcount < 0) - { - bindcount = SPECPDL_INDEX (); - specbind (Qcase_fold_search, - completion_ignore_case ? Qt : Qnil); - } - tem = Fstring_match (XCAR (regexps), eltstring, zero, Qnil); - if (NILP (tem)) - break; - } - if (CONSP (regexps)) - continue; - } + if (!match_regexps (eltstring, Vcompletion_regexp_list, + completion_ignore_case)) + continue; /* Ignore this element if there is a predicate and the predicate doesn't like it. */ @@ -1965,11 +1943,6 @@ with a space are ignored unless STRING itself starts with a space. */) tem = Fcommandp (elt, Qnil); else { - if (bindcount >= 0) - { - unbind_to (bindcount, Qnil); - bindcount = -1; - } tem = type == 3 ? call2 (predicate, elt, HASH_VALUE (XHASH_TABLE (collection), idx - 1)) @@ -1982,9 +1955,6 @@ with a space are ignored unless STRING itself starts with a space. */) } } - if (bindcount >= 0) - unbind_to (bindcount, Qnil); - return Fnreverse (allmatches); } @@ -2068,7 +2038,7 @@ If COLLECTION is a function, it is called with three arguments: the values STRING, PREDICATE and `lambda'. */) (Lisp_Object string, Lisp_Object collection, Lisp_Object predicate) { - Lisp_Object regexps, tail, tem = Qnil; + Lisp_Object tail, tem = Qnil; ptrdiff_t i = 0; CHECK_STRING (string); @@ -2154,20 +2124,9 @@ the values STRING, PREDICATE and `lambda'. */) return call3 (collection, string, predicate, Qlambda); /* Reject this element if it fails to match all the regexps. */ - if (CONSP (Vcompletion_regexp_list)) - { - ptrdiff_t count = SPECPDL_INDEX (); - specbind (Qcase_fold_search, completion_ignore_case ? Qt : Qnil); - for (regexps = Vcompletion_regexp_list; CONSP (regexps); - regexps = XCDR (regexps)) - { - /* We can test against STRING, because if we got here, then - the element is equivalent to it. */ - if (NILP (Fstring_match (XCAR (regexps), string, Qnil, Qnil))) - return unbind_to (count, Qnil); - } - unbind_to (count, Qnil); - } + if (!match_regexps (string, Vcompletion_regexp_list, + completion_ignore_case)) + return Qnil; /* Finally, check the predicate. */ if (!NILP (predicate)) -- 2.39.2