9os

commit e6a49e347382074b4fc3e9c9088ef5c82244efea
parent 72132b63edb25a63073636e379749ee395666ed5
Author: Roberto Vargas <roberto.vargas@arm.com>
Date:   Fri,  2 Nov 2018 14:21:43 +0000

[libc] Add strtoull

Diffstat:
M
src/libc/stdlib/Makefile
 | 
1
+
A
src/libc/stdlib/strtoull.c
 | 
66
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 67 insertions(+), 0 deletions(-)
diff --git a/src/libc/stdlib/Makefile b/src/libc/stdlib/Makefile
@@ -22,5 +22,6 @@ OBJS = __abs.o\
        qsort.o\
        rand.o\
        realloc.o\
+       strtoull.o\
 
 all: $(OBJS)
diff --git a/src/libc/stdlib/strtoull.c b/src/libc/stdlib/strtoull.c
@@ -0,0 +1,66 @@
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+#undef strtoull
+
+unsigned long long
+strtoull(const char *s, char **end, int base)
+{
+	int d, sign = 1;
+	unsigned long long n;
+	static char digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+	const char *t, *p;
+
+	while (isspace(*s))
+		++s;
+
+	switch (*s) {
+	case '-':
+		sign = -1;
+	case '+':
+		++s;
+	}
+
+	if (base == 0) {
+		if (*s == '0' && toupper(s[1]) == 'x')
+			base = 16;
+		else if (*s == '0')
+			base = 8;
+		else
+			base = 10;
+	}
+
+	if (base == 16 && *s == '0' && toupper(s[1]) == 'X')
+		s += 2;
+	else if (base == 8 && *s == '0')
+		s++;
+
+	n = 0;
+	for (t = s; p = strchr(toupper(*t), digits); ++t) {
+		if ((d = p - digits) >= base)
+			break;
+		if (n > base/ULLONG_MAX)
+			goto overflow;
+		n *= base;
+		if (d > ULLONG_MAX - n)
+			goto overflow;
+		n += d;
+	}
+
+
+	if (end)
+		*end = t;
+	if (n == 0 && s == t)
+		errno = EINVAL;
+	return n*sign;;
+
+overflow:
+	if (end)
+		*end = t;
+	errno = ERANGE;
+
+	return ULLONG_MAX;
+}