1import math
2import os
3
4import infra.basetest
5
6
7class TestBc(infra.basetest.BRTest):
8    config = infra.basetest.BASIC_TOOLCHAIN_CONFIG + \
9        """
10        BR2_PACKAGE_BC=y
11        BR2_TARGET_ROOTFS_CPIO=y
12        # BR2_TARGET_ROOTFS_TAR is not set
13        """
14
15    def test_run(self):
16        cpio_file = os.path.join(self.builddir, "images", "rootfs.cpio")
17        self.emulator.boot(arch="armv5",
18                           kernel="builtin",
19                           options=["-initrd", cpio_file])
20        self.emulator.login()
21
22        # Check the program executes.
23        self.assertRunOk("bc --version")
24
25        # We check a square root function of a number slightly larger
26        # than 32 bits.
27        value = 123456
28        squared_value = value ** 2
29        bc_expr = f"sqrt({squared_value})"
30        cmd = f"echo '{bc_expr}' | bc"
31        output, exit_code = self.emulator.run(cmd)
32        self.assertEqual(exit_code, 0)
33        self.assertEqual(int(output[0]), value)
34
35        # Perform an integer exponentiation producing a large number.
36        base = 3
37        exponent = 4567
38        expected_value = base ** exponent
39        bc_expr = f"{base} ^ {exponent}"
40        cmd = f"echo '{bc_expr}' | BC_LINE_LENGTH=0 bc"
41        output, exit_code = self.emulator.run(cmd)
42        self.assertEqual(exit_code, 0)
43        self.assertEqual(int(output[0]), expected_value)
44
45        # Test a basic output base conversion of a large number.
46        hex_str = "DEADBEEF0000ABADC0DE00008BADF00D"
47        hex_base = 16
48        value = int(hex_str, base=hex_base)
49        bc_expr = f"obase={hex_base} ; {value}"
50        cmd = f"echo '{bc_expr}' | bc"
51        output, exit_code = self.emulator.run(cmd)
52        self.assertEqual(exit_code, 0)
53        self.assertEqual(output[0], hex_str)
54
55        # Test a floating point computation by estimating Pi. Since we
56        # use the bc arc-tangent a() function, we need the '-l'
57        # option.
58        bc_expr = "4 * a(1)"
59        cmd = f"echo '{bc_expr}' | bc -l"
60        output, exit_code = self.emulator.run(cmd)
61        self.assertEqual(exit_code, 0)
62        self.assertAlmostEqual(float(output[0]), math.pi, places=16)
63