diff options
| -rw-r--r-- | ChangeLog | 4 | ||||
| -rw-r--r-- | include/ruby/intern.h | 1 | ||||
| -rw-r--r-- | string.c | 34 |
3 files changed, 39 insertions, 0 deletions
@@ -1,3 +1,7 @@ +Tue Aug 12 19:07:02 2008 Nobuyoshi Nakada <nobu@ruby-lang.org> + + * string.c (rb_str_drop): new function to drop first bytes. + Tue Aug 12 18:58:48 2008 Koichi Sasada <ko1@atdot.net> * vm.c, vm_insnhelper.c (vm_define_method): move diff --git a/include/ruby/intern.h b/include/ruby/intern.h index 58432e3fe8..fb5e1380f3 100644 --- a/include/ruby/intern.h +++ b/include/ruby/intern.h @@ -580,6 +580,7 @@ int rb_str_hash_cmp(VALUE,VALUE); int rb_str_comparable(VALUE, VALUE); int rb_str_cmp(VALUE, VALUE); VALUE rb_str_equal(VALUE str1, VALUE str2); +VALUE rb_str_drop(VALUE, long); void rb_str_update(VALUE, long, long, VALUE); VALUE rb_str_inspect(VALUE); VALUE rb_str_dump(VALUE); @@ -2829,9 +2829,43 @@ rb_str_aref_m(int argc, VALUE *argv, VALUE str) return rb_str_aref(str, argv[0]); } +VALUE +rb_str_drop(VALUE str, long len) +{ + char *ptr = RSTRING_PTR(str); + long olen = RSTRING_LEN(str), nlen; + + str_modifiable(str); + if (len > olen) len = olen; + nlen = olen - len; + if (nlen <= RSTRING_EMBED_LEN_MAX) { + char *oldptr = ptr; + int fl = (RBASIC(str)->flags & (STR_NOEMBED|ELTS_SHARED)); + STR_SET_EMBED(str); + STR_SET_EMBED_LEN(str, nlen); + ptr = RSTRING(str)->as.ary; + memcpy(ptr, oldptr + len, nlen); + if (fl == STR_NOEMBED) xfree(oldptr); + } + else { + if (!STR_SHARED_P(str)) rb_str_new4(str); + ptr = RSTRING(str)->as.heap.ptr += len; + RSTRING(str)->as.heap.len = nlen; + } + ptr[nlen] = 0; + ENC_CODERANGE_CLEAR(str); + return str; +} + static void rb_str_splice_0(VALUE str, long beg, long len, VALUE val) { + if (beg == 0 && RSTRING_LEN(val) == 0) { + rb_str_drop(str, len); + OBJ_INFECT(str, val); + return; + } + rb_str_modify(str); if (len < RSTRING_LEN(val)) { /* expand string */ |