bpo-30103: Allow Uuencode in Python using backtick as zero instead of space (#1326)

1 files changed, 12 insertions, 4 deletions

diff --git a/Modules/binascii.c b/Modules/binascii.c
index fbd2320..1f9ff5a 100644
--- a/Modules/binascii.c
+++ b/Modules/binascii.c
@@ -335,13 +335,15 @@ binascii.b2a_uu
 
     data: Py_buffer
     /
+    *
+    backtick: bool(accept={int}) = False
 
 Uuencode line of data.
 [clinic start generated code]*/
 
 static PyObject *
-binascii_b2a_uu_impl(PyObject *module, Py_buffer *data)
-/*[clinic end generated code: output=0070670e52e4aa6b input=00fdf458ce8b465b]*/
+binascii_b2a_uu_impl(PyObject *module, Py_buffer *data, int backtick)
+/*[clinic end generated code: output=b1b99de62d9bbeb8 input=b26bc8d32b6ed2f6]*/
 {
     unsigned char *ascii_data;
     const unsigned char *bin_data;
@@ -367,7 +369,10 @@ binascii_b2a_uu_impl(PyObject *module, Py_buffer *data)
         return NULL;
 
     /* Store the length */
-    *ascii_data++ = ' ' + (bin_len & 077);
+    if (backtick && !bin_len)
+        *ascii_data++ = '`';
+    else
+        *ascii_data++ = ' ' + bin_len;
 
     for( ; bin_len > 0 || leftbits != 0 ; bin_len--, bin_data++ ) {
         /* Shift the data (or padding) into our buffer */
@@ -381,7 +386,10 @@ binascii_b2a_uu_impl(PyObject *module, Py_buffer *data)
         while ( leftbits >= 6 ) {
             this_ch = (leftchar >> (leftbits-6)) & 0x3f;
             leftbits -= 6;
-            *ascii_data++ = this_ch + ' ';
+            if (backtick && !this_ch)
+                *ascii_data++ = '`';
+            else
+                *ascii_data++ = this_ch + ' ';
         }
     }
     *ascii_data++ = '\n';       /* Append a courtesy newline */