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[Qemu-devel] [PATCH v2 1/9] cutils: Add qemu_strtod() and qemu_strtod_fi
From: |
David Hildenbrand |
Subject: |
[Qemu-devel] [PATCH v2 1/9] cutils: Add qemu_strtod() and qemu_strtod_finite() |
Date: |
Tue, 20 Nov 2018 10:25:34 +0100 |
Let's provide a wrapper for strtod().
Reviewed-by: Eric Blake <address@hidden>
Signed-off-by: David Hildenbrand <address@hidden>
---
include/qemu/cutils.h | 2 ++
util/cutils.c | 65 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 67 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..c965dbfcad 100644
--- a/util/cutils.c
+++ b/util/cutils.c
@@ -544,6 +544,71 @@ 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.
+ *
+ * This is a wrapper around strtod() that is harder to misuse.
+ * Semantics of @nptr and @endptr match strtod() with differences
+ * noted below.
+ *
+ * @nptr may be null, and no conversion is performed then.
+ *
+ * If no conversion is performed, store @nptr in address@hidden and return
+ * -EINVAL.
+ *
+ * If @endptr is null, and the string isn't fully converted, return
+ * -EINVAL. This is the case when the pointer that would be stored in
+ * a non-null @endptr points to a character other than '\0'.
+ *
+ * If the conversion overflows, store +/-HUGE_VAL in @result, depending
+ * on the sign, and return -ERANGE.
+ *
+ * If the conversion underflows, store ±0.0 in @result, depending on the
+ * sign, and return -ERANGE.
+ *
+ * Else store the converted value in @result, and return zero.
+ */
+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_strtod(), except that "NaN" and "inf" are rejected
+ * with -EINVAL and no conversion is performed.
+ */
+int qemu_strtod_finite(const char *nptr, const char **endptr, double *result)
+{
+ double tmp;
+ int ret;
+
+ ret = qemu_strtod(nptr, endptr, &tmp);
+ if (ret) {
+ return ret;
+ } else if (!isfinite(tmp)) {
+ if (endptr) {
+ *endptr = nptr;
+ }
+ return -EINVAL;
+ }
+
+ *result = tmp;
+ 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
[Qemu-devel] [PATCH v2 3/9] qapi: Fix string-input-visitor to reject NaN and infinities, David Hildenbrand, 2018/11/20
[Qemu-devel] [PATCH v2 4/9] qapi: Use qemu_strtod_finite() in qobject-input-visitor, David Hildenbrand, 2018/11/20
[Qemu-devel] [PATCH v2 5/9] test-string-input-visitor: Add more tests, David Hildenbrand, 2018/11/20