[Qemu-devel] [PATCH v1 1/9] cutils: add qemu_strtod() and qemu_strtod_finite()

[David Hildenbrand <david@redhat.com>]

Let's provide a wrapper for strtod().

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 include/qemu/cutils.h |  2 ++
 util/cutils.c         | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/include/qemu/cutils.h b/include/qemu/cutils.h
index 7071bfe2d4..756b41c193 100644
--- a/include/qemu/cutils.h
+++ b/include/qemu/cutils.h
@@ -146,6 +146,8 @@ int qemu_strtoi64(const char *nptr, const char **endptr, int base,
                   int64_t *result);
 int qemu_strtou64(const char *nptr, const char **endptr, int base,
                   uint64_t *result);
+int qemu_strtod(const char *nptr, const char **endptr, double *result);
+int qemu_strtod_finite(const char *nptr, const char **endptr, double *result);
 
 int parse_uint(const char *s, unsigned long long *value, char **endptr,
                int base);
diff --git a/util/cutils.c b/util/cutils.c
index 698bd315bd..7868a683e8 100644
--- a/util/cutils.c
+++ b/util/cutils.c
@@ -544,6 +544,44 @@ int qemu_strtou64(const char *nptr, const char **endptr, int base,
     return check_strtox_error(nptr, ep, endptr, errno);
 }
 
+/**
+ * Convert string @nptr to a double.
+ *
+ * Works like qemu_strtoul(), except it stores +/-HUGE_VAL on
+ * overflow/underflow.
+ */
+int qemu_strtod(const char *nptr, const char **endptr, double *result)
+{
+    char *ep;
+
+    if (!nptr) {
+        if (endptr) {
+            *endptr = nptr;
+        }
+        return -EINVAL;
+    }
+
+    errno = 0;
+    *result = strtod(nptr, &ep);
+    return check_strtox_error(nptr, ep, endptr, errno);
+}
+
+/**
+ * Convert string @nptr to a finite double.
+ *
+ * Works like qemu_strtoul(), except it stores +/-HUGE_VAL on
+ * overflow/underflow. "NaN" or "inf" are rejcted with -EINVAL.
+ */
+int qemu_strtod_finite(const char *nptr, const char **endptr, double *result)
+{
+    int ret = qemu_strtod(nptr, endptr, result);
+
+    if (!ret && !isfinite(*result)) {
+        return -EINVAL;
+    }
+    return ret;
+}
+
 /**
  * Searches for the first occurrence of 'c' in 's', and returns a pointer
  * to the trailing null byte if none was found.
-- 
2.17.2