Fix STRING_compare function to work correctly with strings containing zeros.

1 files changed, 11 insertions, 1 deletions

diff --git a/numpy/core/src/arraytypes.inc.src b/numpy/core/src/arraytypes.inc.src
index dbee57c33..fd43b4c58 100644
--- a/numpy/core/src/arraytypes.inc.src
+++ b/numpy/core/src/arraytypes.inc.src
@@ -1679,7 +1679,17 @@ OBJECT_compare(PyObject **ip1, PyObject **ip2, PyArrayObject *ap)
 static int
 STRING_compare(char *ip1, char *ip2, PyArrayObject *ap)
 {
-        return strncmp(ip1, ip2, ap->descr->elsize);
+    const unsigned char *c1 = (unsigned char *)ip1;
+    const unsigned char *c2 = (unsigned char *)ip2;
+    const size_t len = ap->descr->elsize;
+    size_t i;
+
+    for(i = 0; i < len; ++i) {
+        if (c1[i] != c2[i]) {
+            return (c1[i] > c2[i]) ? 1 : -1;
+        }
+    }
+    return 0;
 }
 
 /* taken from Python */