1 files changed, 88 insertions, 0 deletions
diff --git a/pc-bios/s390-ccw/libc.c b/pc-bios/s390-ccw/libc.c
new file mode 100644
index 0000000000..38ea77d7aa
--- /dev/null
+++ b/pc-bios/s390-ccw/libc.c
@@ -0,0 +1,88 @@
+/*
+ * libc-style definitions and functions
+ *
+ * Copyright 2018 IBM Corp.
+ * Author(s): Collin L. Walling <walling@linux.vnet.ibm.com>
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include "libc.h"
+#include "s390-ccw.h"
+
+/**
+ * atoui:
+ * @str: the string to be converted.
+ *
+ * Given a string @str, convert it to an integer. Leading spaces are
+ * ignored. Any other non-numerical value will terminate the conversion
+ * and return 0. This function only handles numbers between 0 and
+ * UINT64_MAX inclusive.
+ *
+ * Returns: an integer converted from the string @str, or the number 0
+ * if an error occurred.
+ */
+uint64_t atoui(const char *str)
+{
+    int val = 0;
+
+    if (!str || !str[0]) {
+        return 0;
+    }
+
+    while (*str == ' ') {
+        str++;
+    }
+
+    while (*str) {
+        if (!isdigit(*str)) {
+            break;
+        }
+        val = val * 10 + *str - '0';
+        str++;
+    }
+
+    return val;
+}
+
+/**
+ * uitoa:
+ * @num: an integer (base 10) to be converted.
+ * @str: a pointer to a string to store the conversion.
+ * @len: the length of the passed string.
+ *
+ * Given an integer @num, convert it to a string. The string @str must be
+ * allocated beforehand. The resulting string will be null terminated and
+ * returned. This function only handles numbers between 0 and UINT64_MAX
+ * inclusive.
+ *
+ * Returns: the string @str of the converted integer @num
+ */
+char *uitoa(uint64_t num, char *str, size_t len)
+{
+    size_t num_idx = 1; /* account for NUL */
+    uint64_t tmp = num;
+
+    IPL_assert(str != NULL, "uitoa: no space allocated to store string");
+
+    /* Count indices of num */
+    while ((tmp /= 10) != 0) {
+        num_idx++;
+    }
+
+    /* Check if we have enough space for num and NUL */
+    IPL_assert(len > num_idx, "uitoa: array too small for conversion");
+
+    str[num_idx--] = '\0';
+
+    /* Convert int to string */
+    while (num_idx >= 0) {
+        str[num_idx--] = num % 10 + '0';
+        num /= 10;
+    }
+
+    return str;
+}