Fixed printf formating.

src/string.cpp

@@ -736,13 +736,28 @@ namespace bx
 				len = min(_param.width, len);
 			}
 
-			int32_t padding = _param.width > len ? _param.width - len : 0;
-			bool sign = _param.sign && len > 1 && _str[0] != '-';
-			padding = padding > 0 ? padding - sign : 0;
+			const bool hasSign = _param.sign || _str[0] == '-';
+			char sign = hasSign ? _str[0] == '-' ? '-' : '+' : '\0';
+
+			const char* str = _str;
+			if (str[0] == '-')
+			{
+				str++;
+				len--;
+			}
+
+			int32_t padding = _param.width > len ? _param.width - len - hasSign: 0;
 
 			if (!_param.left)
 			{
-				size += writeRep(_writer, _param.fill, padding, _err);
+				if (' '  != _param.fill
+				&&  '\0' != sign)
+				{
+					size += write(_writer, sign, _err);
+					sign = '\0';
+				}
+
+				size += writeRep(_writer, _param.fill, max(0, padding), _err);
 			}
 
 			if (NULL == _str)
@@ -753,17 +768,17 @@ namespace bx
 			{
 				for (int32_t ii = 0; ii < len; ++ii)
 				{
-					size += write(_writer, toUpper(_str[ii]), _err);
+					size += write(_writer, toUpper(str[ii]), _err);
 				}
 			}
-			else if (sign)
-			{
-				size += write(_writer, '+', _err);
-				size += write(_writer, _str, len, _err);
-			}
 			else
 			{
-				size += write(_writer, _str, len, _err);
+				if ('\0' != sign)
+				{
+					size += write(_writer, sign, _err);
+				}
+
+				size += write(_writer, str, len, _err);
 			}
 
 			if (_param.left)

tests/vsnprintf_test.cpp

@@ -92,6 +92,10 @@ TEST_CASE("vsnprintf d/i/o/u/x")
 	REQUIRE(test("1234ABCD            ", "%-20X",  0x1234abcd) );
 	REQUIRE(test("edcb5433            ", "%-20x", -0x1234abcd) );
 	REQUIRE(test("EDCB5433            ", "%-20X", -0x1234abcd) );
+	REQUIRE(test("            1234abcd", "% 20x",  0x1234abcd) );
+	REQUIRE(test("            1234ABCD", "% 20X",  0x1234abcd) );
+	REQUIRE(test("            edcb5433", "% 20x", -0x1234abcd) );
+	REQUIRE(test("            EDCB5433", "% 20X", -0x1234abcd) );
 	REQUIRE(test("0000000000001234abcd", "%020x",  0x1234abcd) );
 	REQUIRE(test("0000000000001234ABCD", "%020X",  0x1234abcd) );
 	REQUIRE(test("000000000000edcb5433", "%020x", -0x1234abcd) );
@@ -106,6 +110,18 @@ TEST_CASE("vsnprintf d/i/o/u/x")
 	REQUIRE(test("0xfffffff",  "0x%07x", -1) );
 	REQUIRE(test("0xffffffff", "0x%08x", -1) );
 
+	REQUIRE(test("  -1", "% 4i", -1) );
+	REQUIRE(test("  -1", "% 4i", -1) );
+	REQUIRE(test("   0", "% 4i",  0) );
+	REQUIRE(test("   1", "% 4i",  1) );
+	REQUIRE(test("  +1", "%+4i",  1) );
+	REQUIRE(test("  +0", "%+4i",  0) );
+	REQUIRE(test("  -1", "%+4i", -1) );
+	REQUIRE(test("0001", "%04i",  1) );
+	REQUIRE(test("0000", "%04i",  0) );
+	REQUIRE(test("-001", "%04i", -1) );
+	REQUIRE(test("+001", "%+04i", 1) );
+
 	if (BX_ENABLED(BX_ARCH_32BIT) )
 	{
 		REQUIRE(test("2147483647", "%jd", INTMAX_MAX) );