Implement constcharpsize2str in rffi.

2 files changed, 27 insertions, 0 deletions

diff --git a/rpython/rtyper/lltypesystem/rffi.py b/rpython/rtyper/lltypesystem/rffi.py
index 87e424522d..8c50b8b3b6 100644
--- a/rpython/rtyper/lltypesystem/rffi.py
+++ b/rpython/rtyper/lltypesystem/rffi.py
@@ -1038,6 +1038,16 @@ def constcharp2str(cp):
     return charp2str(cp)
 constcharp2str._annenforceargs_ = [lltype.SomePtr(CONST_CCHARP)]
 
+
+def constcharpsize2str(cp, size):
+    """
+    Like charpsize2str, but takes a CONST_CCHARP instead
+    """
+    cp = cast(CCHARP, cp)
+    return charpsize2str(cp, size)
+constcharpsize2str._annenforceargs_ = [lltype.SomePtr(CONST_CCHARP), int]
+
+
 @not_rpython
 def _deprecated_get_nonmovingbuffer(*args):
     raise Exception(
diff --git a/rpython/rtyper/lltypesystem/test/test_rffi.py b/rpython/rtyper/lltypesystem/test/test_rffi.py
index ed894ddc46..9218448182 100644
--- a/rpython/rtyper/lltypesystem/test/test_rffi.py
+++ b/rpython/rtyper/lltypesystem/test/test_rffi.py
@@ -169,6 +169,23 @@ class BaseTestRffi:
         xf = self.compile(f, [], backendopt=False)
         assert xf() == 3
 
+    def test_constcharpsize2str(self):
+        def f():
+            l_buf = lltype.malloc(CCHARP.TO, 5, flavor='raw')
+            l_buf[0] = 'A'
+            l_buf[1] = 'B'
+            l_buf[2] = 'C'
+            l_buf[3] = '\x00'
+            l_buf[4] = 'E'
+            l_constbuf = cast(CONST_CCHARP, l_buf)
+            res = constcharpsize2str(l_constbuf, 5)
+            lltype.free(l_buf, flavor='raw')
+            return res
+
+        assert f() == "ABC\x00E"
+        xf = self.compile(f, [], backendopt=False)
+        assert xf() == "ABC\x00E"
+
     def test_stringstar(self):
         c_source = """
         #include <string.h>