diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | array.c | 24 |
2 files changed, 20 insertions, 9 deletions
@@ -1,4 +1,7 @@ -Mon Aug 3 13:05:22 2009 Nobuyoshi Nakada <nobu@ruby-lang.org> +Mon Aug 3 15:48:40 2009 Nobuyoshi Nakada <nobu@ruby-lang.org> + + * array.c (rb_ary_{permutation,combination}): disallow reentrance + with continuation since work-buffers cannot restore. * array.c (rb_ary_{permutation,combination,product}): must not use ary_discard on strings. @@ -3647,6 +3647,9 @@ rb_ary_cycle(int argc, VALUE *argv, VALUE ary) } #define tmpbuf(n, size) rb_str_tmp_new((n)*(size)) +#define tmpbuf_discard(s) (rb_str_resize((s), 0L), RBASIC(s)->klass = rb_cString) +#define tmpary(n) rb_ary_tmp_new(n) +#define tmpary_discard(a) (ary_discard(a), RBASIC(a)->klass = rb_cArray) /* * Recursively compute permutations of r elements of the set [0..n-1]. @@ -3684,6 +3687,9 @@ permute0(long n, long r, long *p, long index, int *used, VALUE values) for (j = 0; j < r; j++) result_array[j] = values_array[p[j]]; ARY_SET_LEN(result, r); rb_yield(result); + if (RBASIC(values)->klass) { + rb_raise(rb_eRuntimeError, "permute reentered"); + } } } } @@ -3748,8 +3754,8 @@ rb_ary_permutation(int argc, VALUE *argv, VALUE ary) for (i = 0; i < n; i++) used[i] = 0; /* initialize array */ permute0(n, r, p, 0, used, ary0); /* compute and yield permutations */ - rb_str_resize(t0, 0L); - rb_str_resize(t1, 0L); + tmpbuf_discard(t0); + tmpbuf_discard(t1); RBASIC(ary0)->klass = rb_cArray; } return ary; @@ -3822,11 +3828,10 @@ rb_ary_combination(VALUE ary, VALUE num) volatile VALUE t0 = tmpbuf(n+1, sizeof(long)); long *stack = (long*)RSTRING_PTR(t0); long nlen = combi_len(len, n); - volatile VALUE cc = rb_ary_new2(n); + volatile VALUE cc = tmpary(n); VALUE *chosen = RARRAY_PTR(cc); long lev = 0; - RBASIC(cc)->klass = 0; MEMZERO(stack, long, n); stack[0] = -1; for (i = 0; i < nlen; i++) { @@ -3835,12 +3840,15 @@ rb_ary_combination(VALUE ary, VALUE num) chosen[lev] = RARRAY_PTR(ary)[stack[lev+1] = stack[lev]+1]; } rb_yield(rb_ary_new4(n, chosen)); + if (RBASIC(t0)->klass) { + rb_raise(rb_eRuntimeError, "combination reentered"); + } do { stack[lev--]++; } while (lev && (stack[lev+1]+n == len+lev+1)); } - rb_str_resize(t0, 0L); - ary_discard(cc); + tmpbuf_discard(t0); + tmpary_discard(cc); } return ary; } @@ -3918,8 +3926,8 @@ rb_ary_product(int argc, VALUE *argv, VALUE ary) counters[m]++; } } - rb_str_resize(t0, 0L); - rb_str_resize(t1, 0L); + tmpbuf_discard(t0); + tmpbuf_discard(t1); return result; } |