Issue #29004: Merge crc_hqx() doc from 3.6

vadmium · vadmium · commit 9e40afe20a73 · 2016-12-24T07:45:56.000Z
diff --git a/Doc/library/binascii.rst b/Doc/library/binascii.rst
@@ -116,8 +116,10 @@ The :mod:`binascii` module defines the following functions:
 
 .. function:: crc_hqx(data, value)
 
-   Compute the binhex4 crc value of *data*, starting with *value* as the
-   initial crc, and return the result.
+   Compute a 16-bit CRC value of *data*, starting with *value* as the
+   initial CRC, and return the result.  This uses the CRC-CCITT polynomial
+   *x*:sup:`16` + *x*:sup:`12` + *x*:sup:`5` + 1, often represented as
+   0x1021.  This CRC is used in the binhex4 format.
 
 
 .. function:: crc32(data[, value])
diff --git a/Modules/binascii.c b/Modules/binascii.c
@@ -900,12 +900,12 @@ binascii.crc_hqx -> unsigned_int
     crc: unsigned_int(bitwise=True)
     /
 
-Compute hqx CRC incrementally.
+Compute CRC-CCITT incrementally.
 [clinic start generated code]*/
 
 static unsigned int
 binascii_crc_hqx_impl(PyObject *module, Py_buffer *data, unsigned int crc)
-/*[clinic end generated code: output=8ec2a78590d19170 input=add8c53712ccceda]*/
+/*[clinic end generated code: output=8ec2a78590d19170 input=f18240ff8c705b79]*/
 {
     const unsigned char *bin_data;
     Py_ssize_t len;
diff --git a/Modules/clinic/binascii.c.h b/Modules/clinic/binascii.c.h
@@ -263,7 +263,7 @@ PyDoc_STRVAR(binascii_crc_hqx__doc__,
 "crc_hqx($module, data, crc, /)\n"
 "--\n"
 "\n"
-"Compute hqx CRC incrementally.");
+"Compute CRC-CCITT incrementally.");
 
 #define BINASCII_CRC_HQX_METHODDEF    \
     {"crc_hqx", (PyCFunction)binascii_crc_hqx, METH_VARARGS, binascii_crc_hqx__doc__},
@@ -550,4 +550,4 @@ binascii_b2a_qp(PyObject *module, PyObject **args, Py_ssize_t nargs, PyObject *k
 
     return return_value;
 }
-/*[clinic end generated code: output=1f8d6e48f75f6d1e input=a9049054013a1b77]*/
+/*[clinic end generated code: output=458eb09731cb7877 input=a9049054013a1b77]*/

Original file line number	Diff line number	Diff line change
`@@ -900,12 +900,12 @@ binascii.crc_hqx -> unsigned_int`
`900`	`900`	`crc: unsigned_int(bitwise=True)`
`901`	`901`	`/`
`902`	`902`
`903`		`-Compute hqx CRC incrementally.`
	`903`	`+Compute CRC-CCITT incrementally.`
`904`	`904`	`[clinic start generated code]*/`
`905`	`905`
`906`	`906`	`static unsigned int`
`907`	`907`	`binascii_crc_hqx_impl(PyObject module, Py_buffer data, unsigned int crc)`
`908`		`-/[clinic end generated code: output=8ec2a78590d19170 input=add8c53712ccceda]/`
	`908`	`+/[clinic end generated code: output=8ec2a78590d19170 input=f18240ff8c705b79]/`
`909`	`909`	`{`
`910`	`910`	`const unsigned char *bin_data;`
`911`	`911`	`Py_ssize_t len;`