Proper constant parsing

1 files changed, 35 insertions, 0 deletions

diff --git a/caux.c b/caux.c
new file mode 100644
index 0000000..1602c55
--- /dev/null
+++ b/caux.c
@@ -0,0 +1,35 @@
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+#include <math.h>
+
+#include "export.h"
+
+#define PARSE_FP(fp_type, func, huge_val) \
+	fp_type parse_ ## fp_type (Pointer repr, int *status) {\
+		char *f = (char*)repr;\
+		char *tmp;\
+		fp_type result; \
+		int saved_errno = errno;\
+\
+		errno = 0;\
+		result = func(f, &tmp);\
+\
+		if (errno == ERANGE) {\
+			if (result == huge_val)\
+				*status = 1;\
+			else\
+				*status = -1;\
+		}\
+		errno = saved_errno;\
+\
+		if (f + strlen(f) != tmp)\
+			*status = 2;\
+		return result;\
+	}
+
+PARSE_FP(float, strtof, HUGE_VALF)
+PARSE_FP(double, strtod, HUGE_VAL)