From 506e11a886d71f368f171c4bba61ca987f67b355 Mon Sep 17 00:00:00 2001 From: nobu Date: Tue, 13 Sep 2016 12:11:57 +0000 Subject: string.c: STR_EMBEDABLE_P * string.c (STR_EMBEDABLE_P): extract the predicate macro to tell if the given length is capable in an embedded string, and fix possible integer overflow. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56151 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- string.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'string.c') diff --git a/string.c b/string.c index 450a5590e6..726938cae2 100644 --- a/string.c +++ b/string.c @@ -165,6 +165,9 @@ VALUE rb_cSymbol; #define SHARABLE_SUBSTRING_P(beg, len, end) 1 #endif +#define STR_EMBEDABLE_P(len, termlen) \ + ((len) <= RSTRING_EMBED_LEN_MAX + 1 - (termlen)) + static VALUE str_replace_shared_without_enc(VALUE str2, VALUE str); static VALUE str_new_shared(VALUE klass, VALUE str); static VALUE str_new_frozen(VALUE klass, VALUE orig); @@ -1068,7 +1071,7 @@ str_replace_shared_without_enc(VALUE str2, VALUE str) long len; RSTRING_GETMEM(str, ptr, len); - if (len+termlen <= RSTRING_EMBED_LEN_MAX+1) { + if (STR_EMBEDABLE_P(len, termlen)) { char *ptr2 = RSTRING(str2)->as.ary; STR_SET_EMBED(str2); memcpy(ptr2, RSTRING_PTR(str), len); @@ -2524,14 +2527,14 @@ rb_str_resize(VALUE str, long len) const int termlen = TERM_LEN(str); if (STR_EMBED_P(str)) { if (len == slen) return str; - if (len + termlen <= RSTRING_EMBED_LEN_MAX + 1) { + if (STR_EMBEDABLE_P(len, termlen)) { STR_SET_EMBED_LEN(str, len); TERM_FILL(RSTRING(str)->as.ary + len, termlen); return str; } str_make_independent_expand(str, slen, len - slen, termlen); } - else if (len + termlen <= RSTRING_EMBED_LEN_MAX + 1) { + else if (STR_EMBEDABLE_P(len, termlen)) { char *ptr = STR_HEAP_PTR(str); STR_SET_EMBED(str); if (slen > len) slen = len; -- cgit v1.2.3