use an intermediate box, so "dst" does not have to be initialized

diff --git a/src/lib/util/calc.c b/src/lib/util/calc.c
index 6de3dbf1c0daef3d538b13629ec4f92f8aa763a4..f5966b9a0ee77de9845c01cc8517e841c748886a 100644 (file)
--- a/src/lib/util/calc.c
+++ b/src/lib/util/calc.c
@@ -404,7 +404,6 @@ static int calc_octets(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                memcpy(buf, b->vb_octets, b->vb_length);
                memcpy(buf + b->vb_length, a->vb_octets, a->vb_length);
 
-               fr_value_box_clear_value(dst);
                fr_value_box_memdup_shallow(dst, dst->enumv, buf, len, a->tainted | b->tainted);
                break;
 
@@ -415,7 +414,6 @@ static int calc_octets(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                memcpy(buf, a->vb_octets, a->vb_length);
                memcpy(buf + a->vb_length, b->vb_octets, b->vb_length);
 
-               fr_value_box_clear_value(dst);
                fr_value_box_memdup_shallow(dst, dst->enumv, buf, len, a->tainted | b->tainted);
                break;
 
@@ -439,7 +437,6 @@ static int calc_octets(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
 
                memcpy(buf, a->vb_strvalue, len);
 
-               fr_value_box_clear_value(dst);
                fr_value_box_memdup_shallow(dst, dst->enumv, buf, len, a->tainted | b->tainted);
                break;
 
@@ -457,7 +454,6 @@ static int calc_octets(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                        buf[len] = a->vb_octets[len] & b->vb_octets[len];
                }
 
-               fr_value_box_clear_value(dst);
                fr_value_box_memdup_shallow(dst, dst->enumv, buf, a->vb_length, a->tainted | b->tainted);
                break;
 
@@ -471,7 +467,6 @@ static int calc_octets(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                        buf[len] = a->vb_octets[len] | b->vb_octets[len];
                }
 
-               fr_value_box_clear_value(dst);
                fr_value_box_memdup_shallow(dst, dst->enumv, buf, a->vb_length, a->tainted | b->tainted);
                break;
 
@@ -518,7 +513,6 @@ static int calc_string(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                memcpy(buf + b->vb_length, a->vb_strvalue, a->vb_length);
                buf[a->vb_length + b->vb_length] = '\0';
 
-               fr_value_box_clear_value(dst);
                fr_value_box_strdup_shallow(dst, dst->enumv, buf, a->tainted | b->tainted);
                break;
 
@@ -530,7 +524,6 @@ static int calc_string(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                memcpy(buf + a->vb_length, b->vb_strvalue, b->vb_length);
                buf[a->vb_length + b->vb_length] = '\0';
 
-               fr_value_box_clear_value(dst);
                fr_value_box_strdup_shallow(dst, dst->enumv, buf, a->tainted | b->tainted);
                break;
 
@@ -555,7 +548,6 @@ static int calc_string(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_value_box_t cons
                memcpy(buf, a->vb_strvalue, len);
                buf[len] = '\0';
 
-               fr_value_box_clear_value(dst);
                fr_value_box_strdup_shallow(dst, dst->enumv, buf, a->tainted | b->tainted);
                break;
 
@@ -1072,6 +1064,7 @@ int fr_value_calc_binary_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_type_t hint
 {
        int rcode = -1;
        fr_value_box_t one, two;
+       fr_value_box_t out;
 
        fr_assert(fr_type_is_leaf(a->type));
        fr_assert(fr_type_is_leaf(b->type));
@@ -1203,20 +1196,15 @@ int fr_value_calc_binary_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_type_t hint
        case T_OP_LT:
                if (hint != FR_TYPE_BOOL) {
                        fr_strerror_printf("Invalid destination type '%s' for comparison operator",
-                                          fr_table_str_by_value(fr_value_box_type_table, dst->type, "<INVALID>"));
+                                          fr_table_str_by_value(fr_value_box_type_table, hint, "<INVALID>"));
                        goto done;
                }
 
-               fr_value_box_clear_value(dst);
-               fr_value_box_init(dst, FR_TYPE_BOOL, NULL, false);      // just force it...
-
                rcode = fr_value_box_cmp_op(op, a, b);
-               if (rcode < 0) {
-                       goto done;
-               }
+               if (rcode < 0) goto done;
 
+               fr_value_box_init(dst, FR_TYPE_BOOL, NULL, false);
                dst->vb_bool = (rcode > 0);
-               rcode = 0;
                break;
 
        case T_ADD:
@@ -1228,23 +1216,25 @@ int fr_value_calc_binary_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_type_t hint
        case T_OP_PREPEND:
                fr_assert(hint != FR_TYPE_NULL);
 
-               /*
-                *      It's OK to use one of the inputs as the
-                *      output.  But if we don't, ensure that the
-                *      output value box is initialized.
-                */
-               if ((dst != a) && (dst != b)) {
-                       fr_value_box_init(dst, hint, NULL, false);
-               }
-
-               if (!calc_type[dst->type]) {
+               if (!calc_type[hint]) {
                        fr_strerror_printf("Cannot perform any operations for destination type %s",
-                                          fr_table_str_by_value(fr_value_box_type_table, dst->type, "<INVALID>"));
+                                          fr_table_str_by_value(fr_value_box_type_table, hint, "<INVALID>"));
                        rcode = -1;
                        break;
                }
 
-               rcode = calc_type[dst->type](ctx, dst, a, op, b);
+               /*
+                *      It's OK to use one of the inputs as the
+                *      output.  In order to ensure that nothing bad
+                *      happens, we use an intermediate value-box.
+                */
+               fr_value_box_init(&out, hint, NULL, false);
+
+               rcode = calc_type[hint](ctx, &out, a, op, b);
+               if (rcode < 0) goto done;
+
+               fr_value_box_copy_shallow(NULL, dst, &out);
+               dst->tainted = a->tainted | b->tainted;
                break;
 
        default:
@@ -1252,19 +1242,17 @@ int fr_value_calc_binary_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_type_t hint
                break;
        }
 
+done:
        if (rcode == ERR_OVERFLOW) {
                fr_strerror_printf("Value overflows/underflows when calculating answer for %s",
-                                  fr_table_str_by_value(fr_value_box_type_table, dst->type, "<INVALID>"));
+                                  fr_table_str_by_value(fr_value_box_type_table, hint, "<INVALID>"));
 
        } else if (rcode == ERR_INVALID) {
                fr_strerror_printf("Invalid operator %s for destination type %s",
                                   fr_tokens[op],
-                                  fr_table_str_by_value(fr_value_box_type_table, dst->type, "<INVALID>"));
+                                  fr_table_str_by_value(fr_value_box_type_table, hint, "<INVALID>"));
        }
 
-done:
-       if (rcode == 0) dst->tainted = a->tainted | b->tainted;
-
        fr_value_box_clear_value(&one);
        fr_value_box_clear_value(&two);
 
@@ -1281,6 +1269,7 @@ done:
 int fr_value_calc_assignment_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_token_t op, fr_value_box_t const *src)
 {
        int rcode = -1;
+       fr_value_box_t out;
 
        if (!fr_type_is_leaf(dst->type)) {
                fr_strerror_printf("Cannot perform any operations for destination type %s",
@@ -1290,6 +1279,8 @@ int fr_value_calc_assignment_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_token_t
 
        if (!fr_assignment_op[op]) goto invalid;
 
+       fr_value_box_init(&out, dst->type, dst->enumv, false);
+
        switch (op) {
                /*
                 *      These operators are included here for testing
@@ -1301,8 +1292,7 @@ int fr_value_calc_assignment_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_token_t
        case T_OP_SET:
                fr_value_box_clear_value(dst);
                fr_value_box_cast(ctx, dst, dst->type, dst->enumv, src); /* cast, as the RHS might not (yet) be the same! */
-               rcode = 0;
-               break;
+               return 0;
 
                /*
                 *      Just call the binary op function.  It already
@@ -1311,11 +1301,11 @@ int fr_value_calc_assignment_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_token_t
                 *      final step
                 */
        case T_OP_ADD_EQ:
-               rcode = fr_value_calc_binary_op(ctx, dst, dst->type, dst, T_ADD, src);
+               rcode = fr_value_calc_binary_op(ctx, &out, dst->type, dst, T_ADD, src);
                break;
 
        case T_OP_SUB_EQ:
-               rcode = fr_value_calc_binary_op(ctx, dst, dst->type, dst, T_SUB, src);
+               rcode = fr_value_calc_binary_op(ctx, &out, dst->type, dst, T_SUB, src);
                break;
 
        case T_OP_PREPEND:
@@ -1323,11 +1313,11 @@ int fr_value_calc_assignment_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_token_t
                break;
 
        case T_OP_AND_EQ:
-               rcode = fr_value_calc_binary_op(ctx, dst, dst->type, dst, T_OR, src);
+               rcode = fr_value_calc_binary_op(ctx, &out, dst->type, dst, T_OR, src);
                break;
 
        case T_OP_OR_EQ:
-               rcode = fr_value_calc_binary_op(ctx, dst, dst->type, dst, T_AND, src);
+               rcode = fr_value_calc_binary_op(ctx, &out, dst->type, dst, T_AND, src);
                break;
 
        default:
@@ -1351,7 +1341,8 @@ int fr_value_calc_assignment_op(TALLOC_CTX *ctx, fr_value_box_t *dst, fr_token_t
         */
        if (rcode < 0) return -1;
 
-       dst->tainted |= src->tainted;
+       fr_value_box_clear_value(dst);
+       fr_value_box_copy_shallow(NULL, dst, &out);
        return 0;
 }
 
@@ -1436,6 +1427,7 @@ int fr_value_calc_unary_op(TALLOC_CTX *ctx, fr_value_box_t *box, fr_token_t op)
                break;
 
        default:
+               rcode = ERR_INVALID;
                goto invalid;
        }