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-rw-r--r--bin/expr/expr.y215
1 files changed, 69 insertions, 146 deletions
diff --git a/bin/expr/expr.y b/bin/expr/expr.y
index a7f38f5898f5..f2053634e7e5 100644
--- a/bin/expr/expr.y
+++ b/bin/expr/expr.y
@@ -40,13 +40,16 @@ struct val {
} u;
} ;
+char **av;
+int nonposix;
struct val *result;
void assert_to_integer(struct val *);
-int chk_div(intmax_t, intmax_t);
-int chk_minus(intmax_t, intmax_t, intmax_t);
-int chk_plus(intmax_t, intmax_t, intmax_t);
-int chk_times(intmax_t, intmax_t, intmax_t);
+void assert_div(intmax_t, intmax_t);
+void assert_minus(intmax_t, intmax_t, intmax_t);
+void assert_plus(intmax_t, intmax_t, intmax_t);
+void assert_times(intmax_t, intmax_t, intmax_t);
+int compare_vals(struct val *, struct val *);
void free_value(struct val *);
int is_integer(const char *);
int isstring(struct val *);
@@ -73,8 +76,6 @@ int yyerror(const char *);
int yylex(void);
int yyparse(void);
-static int nonposix;
-char **av;
%}
%union
@@ -344,138 +345,77 @@ op_and(struct val *a, struct val *b)
}
}
-struct val *
-op_eq(struct val *a, struct val *b)
+int
+compare_vals(struct val *a, struct val *b)
{
- struct val *r;
+ int r;
- if (isstring (a) || isstring (b)) {
- to_string (a);
- to_string (b);
- r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) == 0));
+ if (isstring(a) || isstring(b)) {
+ to_string(a);
+ to_string(b);
+ r = strcoll(a->u.s, b->u.s);
} else {
assert_to_integer(a);
assert_to_integer(b);
- r = make_integer ((intmax_t)(a->u.i == b->u.i));
+ if (a->u.i > b->u.i)
+ r = 1;
+ else if (a->u.i < b->u.i)
+ r = -1;
+ else
+ r = 0;
}
- free_value (a);
- free_value (b);
- return r;
+ free_value(a);
+ free_value(b);
+ return (r);
}
struct val *
-op_gt(struct val *a, struct val *b)
+op_eq(struct val *a, struct val *b)
{
- struct val *r;
-
- if (isstring (a) || isstring (b)) {
- to_string (a);
- to_string (b);
- r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) > 0));
- } else {
- assert_to_integer(a);
- assert_to_integer(b);
- r = make_integer ((intmax_t)(a->u.i > b->u.i));
- }
+ return (make_integer((intmax_t)(compare_vals(a, b) == 0)));
+}
- free_value (a);
- free_value (b);
- return r;
+struct val *
+op_gt(struct val *a, struct val *b)
+{
+ return (make_integer((intmax_t)(compare_vals(a, b) > 0)));
}
struct val *
op_lt(struct val *a, struct val *b)
{
- struct val *r;
-
- if (isstring (a) || isstring (b)) {
- to_string (a);
- to_string (b);
- r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) < 0));
- } else {
- assert_to_integer(a);
- assert_to_integer(b);
- r = make_integer ((intmax_t)(a->u.i < b->u.i));
- }
-
- free_value (a);
- free_value (b);
- return r;
+ return (make_integer((intmax_t)(compare_vals(a, b) < 0)));
}
struct val *
op_ge(struct val *a, struct val *b)
{
- struct val *r;
-
- if (isstring (a) || isstring (b)) {
- to_string (a);
- to_string (b);
- r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) >= 0));
- } else {
- assert_to_integer(a);
- assert_to_integer(b);
- r = make_integer ((intmax_t)(a->u.i >= b->u.i));
- }
-
- free_value (a);
- free_value (b);
- return r;
+ return (make_integer((intmax_t)(compare_vals(a, b) >= 0)));
}
struct val *
op_le(struct val *a, struct val *b)
{
- struct val *r;
-
- if (isstring (a) || isstring (b)) {
- to_string (a);
- to_string (b);
- r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) <= 0));
- } else {
- assert_to_integer(a);
- assert_to_integer(b);
- r = make_integer ((intmax_t)(a->u.i <= b->u.i));
- }
-
- free_value (a);
- free_value (b);
- return r;
+ return (make_integer((intmax_t)(compare_vals(a, b) <= 0)));
}
struct val *
op_ne(struct val *a, struct val *b)
{
- struct val *r;
-
- if (isstring (a) || isstring (b)) {
- to_string (a);
- to_string (b);
- r = make_integer ((intmax_t)(strcoll (a->u.s, b->u.s) != 0));
- } else {
- assert_to_integer(a);
- assert_to_integer(b);
- r = make_integer ((intmax_t)(a->u.i != b->u.i));
- }
-
- free_value (a);
- free_value (b);
- return r;
+ return (make_integer((intmax_t)(compare_vals(a, b) != 0)));
}
-int
-chk_plus(intmax_t a, intmax_t b, intmax_t r)
+void
+assert_plus(intmax_t a, intmax_t b, intmax_t r)
{
-
- /* sum of two positive numbers must be positive */
- if (a > 0 && b > 0 && r <= 0)
- return 1;
- /* sum of two negative numbers must be negative */
- if (a < 0 && b < 0 && r >= 0)
- return 1;
- /* all other cases are OK */
- return 0;
+ /*
+ * sum of two positive numbers must be positive,
+ * sum of two negative numbers must be negative
+ */
+ if ((a > 0 && b > 0 && r <= 0) ||
+ (a < 0 && b < 0 && r >= 0))
+ errx(ERR_EXIT, "overflow");
}
struct val *
@@ -487,28 +427,22 @@ op_plus(struct val *a, struct val *b)
assert_to_integer(b);
r = make_integer(a->u.i + b->u.i);
- if (chk_plus(a->u.i, b->u.i, r->u.i)) {
- errx(ERR_EXIT, "overflow");
- }
+ assert_plus(a->u.i, b->u.i, r->u.i);
free_value (a);
free_value (b);
return r;
}
-int
-chk_minus(intmax_t a, intmax_t b, intmax_t r)
+void
+assert_minus(intmax_t a, intmax_t b, intmax_t r)
{
/* special case subtraction of INTMAX_MIN */
- if (b == INTMAX_MIN) {
- if (a >= 0)
- return 1;
- else
- return 0;
- }
- /* this is allowed for b != INTMAX_MIN */
- return chk_plus (a, -b, r);
+ if (b == INTMAX_MIN && a < 0)
+ errx(ERR_EXIT, "overflow");
+ /* check addition of negative subtrahend */
+ assert_plus(a, -b, r);
}
struct val *
@@ -520,25 +454,22 @@ op_minus(struct val *a, struct val *b)
assert_to_integer(b);
r = make_integer(a->u.i - b->u.i);
- if (chk_minus(a->u.i, b->u.i, r->u.i)) {
- errx(ERR_EXIT, "overflow");
- }
+ assert_minus(a->u.i, b->u.i, r->u.i);
free_value (a);
free_value (b);
return r;
}
-int
-chk_times(intmax_t a, intmax_t b, intmax_t r)
+void
+assert_times(intmax_t a, intmax_t b, intmax_t r)
{
- /* special case: first operand is 0, no overflow possible */
- if (a == 0)
- return 0;
- /* verify that result of division matches second operand */
- if (r / a != b)
- return 1;
- return 0;
+ /*
+ * if first operand is 0, no overflow is possible,
+ * else result of division test must match second operand
+ */
+ if (a != 0 && r / a != b)
+ errx(ERR_EXIT, "overflow");
}
struct val *
@@ -550,24 +481,21 @@ op_times(struct val *a, struct val *b)
assert_to_integer(b);
r = make_integer(a->u.i * b->u.i);
- if (chk_times(a->u.i, b->u.i, r->u.i)) {
- errx(ERR_EXIT, "overflow");
- }
+ assert_times(a->u.i, b->u.i, r->u.i);
free_value (a);
free_value (b);
return (r);
}
-int
-chk_div(intmax_t a, intmax_t b)
+void
+assert_div(intmax_t a, intmax_t b)
{
- /* div by zero has been taken care of before */
+ if (b == 0)
+ errx(ERR_EXIT, "division by zero");
/* only INTMAX_MIN / -1 causes overflow */
if (a == INTMAX_MIN && b == -1)
- return 1;
- /* everything else is OK */
- return 0;
+ errx(ERR_EXIT, "overflow");
}
struct val *
@@ -578,12 +506,8 @@ op_div(struct val *a, struct val *b)
assert_to_integer(a);
assert_to_integer(b);
- if (b->u.i == 0) {
- errx(ERR_EXIT, "division by zero");
- }
- if (chk_div(a->u.i, b->u.i)) {
- errx(ERR_EXIT, "overflow");
- }
+ /* assert based on operands only, not on result */
+ assert_div(a->u.i, b->u.i);
r = make_integer(a->u.i / b->u.i);
free_value (a);
@@ -598,9 +522,8 @@ op_rem(struct val *a, struct val *b)
assert_to_integer(a);
assert_to_integer(b);
- if (b->u.i == 0) {
- errx(ERR_EXIT, "division by zero");
- }
+ /* pass a=1 to only check for div by zero */
+ assert_div(1, b->u.i);
r = make_integer(a->u.i % b->u.i);
free_value (a);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 00:37:16 +0000