_helpers.c: be smarter when converting unknown integer types to python.

For now assume that long long and unsigned long long are always the
the largest integer types, and convert unknown size integers to Python
via PyLong_FromUnsignedLongLong() or PyLong_FromLongLong(), depending
on the value's sign.

Thanks to Thomas Klausner <tk@giga.or.at> for reporting the problem
and helping  track down the solution.

Signed-off-by: Rob Browning <rlb@defaultvalue.org>

diff --git a/lib/bup/_helpers.c b/lib/bup/_helpers.c
index 0da41562181602dad1f4b1ec2ad9d2abfd5d7b03..ca1053db2245530db3bee5b57a535b6b294a4c1b 100644 (file)
--- a/lib/bup/_helpers.c
+++ b/lib/bup/_helpers.c
@@ -986,13 +986,8 @@ static int normalize_timespec_values(const char *name,
 }
 
 
-#define CHECK_VALUE_FITS(name, value, src_type, dest_type, max_value) \
-if (sizeof(src_type) >= sizeof(dest_type) && (value) > (max_value)) \
-{ \
-    PyErr_SetString(PyExc_OverflowError, \
-                    name " cannot be converted to integer"); \
-    return NULL; \
-}
+#define INTEGER_TO_PY(x) \
+    (((x) >= 0) ? PyLong_FromUnsignedLongLong(x) : PyLong_FromLongLong(x))
 
 
 static PyObject *stat_struct_to_py(const struct stat *st,
@@ -1014,23 +1009,16 @@ static PyObject *stat_struct_to_py(const struct stat *st,
         return NULL;
 
     // We can check the known (via POSIX) signed and unsigned types at
-    // compile time, but not (easily) the unspecified types.  Ideally,
-    // some of these will be optimized out at compile time.
-    CHECK_VALUE_FITS("stat st_mode", st->st_mode, mode_t, PY_LONG_LONG, PY_LLONG_MAX);
-    CHECK_VALUE_FITS("stat st_dev", st->st_dev, dev_t, PY_LONG_LONG, PY_LLONG_MAX);
-    CHECK_VALUE_FITS("stat st_uid", st->st_uid, uid_t, PY_LONG_LONG, PY_LLONG_MAX);
-    CHECK_VALUE_FITS("stat st_gid", st->st_uid, uid_t, PY_LONG_LONG, PY_LLONG_MAX);
-    CHECK_VALUE_FITS("stat st_nlink", st->st_nlink, nlink_t, PY_LONG_LONG, PY_LLONG_MAX);
-    CHECK_VALUE_FITS("stat st_rdev", st->st_rdev, dev_t, PY_LONG_LONG, PY_LLONG_MAX);
-
-    return Py_BuildValue("LKLLLLLL(Ll)(Ll)(Ll)",
-                         (PY_LONG_LONG) st->st_mode,
+    // compile time, but not (easily) the unspecified types, so handle
+    // those via INTEGER_TO_PY().
+    return Py_BuildValue("OKOOOOOL(Ll)(Ll)(Ll)",
+                         INTEGER_TO_PY(st->st_mode),
                          (unsigned PY_LONG_LONG) st->st_ino,
-                         (PY_LONG_LONG) st->st_dev,
-                         (PY_LONG_LONG) st->st_nlink,
-                         (PY_LONG_LONG) st->st_uid,
-                         (PY_LONG_LONG) st->st_gid,
-                         (PY_LONG_LONG) st->st_rdev,
+                         INTEGER_TO_PY(st->st_dev),
+                         INTEGER_TO_PY(st->st_nlink),
+                         INTEGER_TO_PY(st->st_uid),
+                         INTEGER_TO_PY(st->st_gid),
+                         INTEGER_TO_PY(st->st_rdev),
                          (PY_LONG_LONG) st->st_size,
                          (PY_LONG_LONG) atime,
                          (long) atime_ns,