Python code coverage for Modules/binascii.c

#	count	content
1	n/a	/*
2	n/a	** Routines to represent binary data in ASCII and vice-versa
3	n/a	**
4	n/a	** This module currently supports the following encodings:
5	n/a	** uuencode:
6	n/a	** each line encodes 45 bytes (except possibly the last)
7	n/a	** First char encodes (binary) length, rest data
8	n/a	** each char encodes 6 bits, as follows:
9	n/a	** binary: 01234567 abcdefgh ijklmnop
10	n/a	** ascii: 012345 67abcd efghij klmnop
11	n/a	** ASCII encoding method is "excess-space": 000000 is encoded as ' ', etc.
12	n/a	** short binary data is zero-extended (so the bits are always in the
13	n/a	** right place), this does not reflect in the length.
14	n/a	** base64:
15	n/a	** Line breaks are insignificant, but lines are at most 76 chars
16	n/a	** each char encodes 6 bits, in similar order as uucode/hqx. Encoding
17	n/a	** is done via a table.
18	n/a	** Short binary data is filled (in ASCII) with '='.
19	n/a	** hqx:
20	n/a	** File starts with introductory text, real data starts and ends
21	n/a	** with colons.
22	n/a	** Data consists of three similar parts: info, datafork, resourcefork.
23	n/a	** Each part is protected (at the end) with a 16-bit crc
24	n/a	** The binary data is run-length encoded, and then ascii-fied:
25	n/a	** binary: 01234567 abcdefgh ijklmnop
26	n/a	** ascii: 012345 67abcd efghij klmnop
27	n/a	** ASCII encoding is table-driven, see the code.
28	n/a	** Short binary data results in the runt ascii-byte being output with
29	n/a	** the bits in the right place.
30	n/a	**
31	n/a	** While I was reading dozens of programs that encode or decode the formats
32	n/a	** here (documentation? hihi:-) I have formulated Jansen's Observation:
33	n/a	**
34	n/a	** Programs that encode binary data in ASCII are written in
35	n/a	** such a style that they are as unreadable as possible. Devices used
36	n/a	** include unnecessary global variables, burying important tables
37	n/a	** in unrelated sourcefiles, putting functions in include files,
38	n/a	** using seemingly-descriptive variable names for different purposes,
39	n/a	** calls to empty subroutines and a host of others.
40	n/a	**
41	n/a	** I have attempted to break with this tradition, but I guess that that
42	n/a	** does make the performance sub-optimal. Oh well, too bad...
43	n/a	**
44	n/a	** Jack Jansen, CWI, July 1995.
45	n/a	**
46	n/a	** Added support for quoted-printable encoding, based on rfc 1521 et al
47	n/a	** quoted-printable encoding specifies that non printable characters (anything
48	n/a	** below 32 and above 126) be encoded as =XX where XX is the hexadecimal value
49	n/a	** of the character. It also specifies some other behavior to enable 8bit data
50	n/a	** in a mail message with little difficulty (maximum line sizes, protecting
51	n/a	** some cases of whitespace, etc).
52	n/a	**
53	n/a	** Brandon Long, September 2001.
54	n/a	*/
55	n/a
56	n/a	#define PY_SSIZE_T_CLEAN
57	n/a
58	n/a	#include "Python.h"
59	n/a	#include "pystrhex.h"
60	n/a	#ifdef USE_ZLIB_CRC32
61	n/a	#include "zlib.h"
62	n/a	#endif
63	n/a
64	n/a	static PyObject *Error;
65	n/a	static PyObject *Incomplete;
66	n/a
67	n/a	/*
68	n/a	** hqx lookup table, ascii->binary.
69	n/a	*/
70	n/a
71	n/a	#define RUNCHAR 0x90
72	n/a
73	n/a	#define DONE 0x7F
74	n/a	#define SKIP 0x7E
75	n/a	#define FAIL 0x7D
76	n/a
77	n/a	static const unsigned char table_a2b_hqx[256] = {
78	n/a	/* ^@ ^A ^B ^C ^D ^E ^F ^G */
79	n/a	/* 0*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
80	n/a	/* \b \t \n ^K ^L \r ^N ^O */
81	n/a	/* 1*/ FAIL, FAIL, SKIP, FAIL, FAIL, SKIP, FAIL, FAIL,
82	n/a	/* ^P ^Q ^R ^S ^T ^U ^V ^W */
83	n/a	/* 2*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
84	n/a	/* ^X ^Y ^Z ^[ ^\ ^] ^^ ^_ */
85	n/a	/* 3*/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
86	n/a	/* ! " # $ % & ' */
87	n/a	/* 4*/ FAIL, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
88	n/a	/* ( ) * + , - . / */
89	n/a	/* 5*/ 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, FAIL, FAIL,
90	n/a	/* 0 1 2 3 4 5 6 7 */
91	n/a	/* 6*/ 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, 0x13, FAIL,
92	n/a	/* 8 9 : ; < = > ? */
93	n/a	/* 7*/ 0x14, 0x15, DONE, FAIL, FAIL, FAIL, FAIL, FAIL,
94	n/a	/* @ A B C D E F G */
95	n/a	/* 8*/ 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D,
96	n/a	/* H I J K L M N O */
97	n/a	/* 9*/ 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, FAIL,
98	n/a	/* P Q R S T U V W */
99	n/a	/10/ 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, FAIL,
100	n/a	/* X Y Z [ \ ] ^ _ */
101	n/a	/11/ 0x2C, 0x2D, 0x2E, 0x2F, FAIL, FAIL, FAIL, FAIL,
102	n/a	/* ` a b c d e f g */
103	n/a	/12/ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, FAIL,
104	n/a	/* h i j k l m n o */
105	n/a	/13/ 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, FAIL, FAIL,
106	n/a	/* p q r s t u v w */
107	n/a	/14/ 0x3D, 0x3E, 0x3F, FAIL, FAIL, FAIL, FAIL, FAIL,
108	n/a	/* x y z { \| } ~ ^? */
109	n/a	/15/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
110	n/a	/16/ FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
111	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
112	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
113	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
114	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
115	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
116	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
117	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
118	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
119	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
120	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
121	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
122	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
123	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
124	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
125	n/a	FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL, FAIL,
126	n/a	};
127	n/a
128	n/a	static const unsigned char table_b2a_hqx[] =
129	n/a	"!\"#$%&'()*+,-012345689@ABCDEFGHIJKLMNPQRSTUVXYZ[`abcdefhijklmpqr";
130	n/a
131	n/a	static const char table_a2b_base64[] = {
132	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
133	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
134	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63,
135	n/a	52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1, 0,-1,-1, /* Note PAD->0 */
136	n/a	-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14,
137	n/a	15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1,
138	n/a	-1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40,
139	n/a	41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1
140	n/a	};
141	n/a
142	n/a	#define BASE64_PAD '='
143	n/a
144	n/a	/* Max binary chunk size; limited only by available memory */
145	n/a	#define BASE64_MAXBIN ((PY_SSIZE_T_MAX - 3) / 2)
146	n/a
147	n/a	static const unsigned char table_b2a_base64[] =
148	n/a	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
149	n/a
150	n/a
151	n/a
152	n/a	static const unsigned short crctab_hqx[256] = {
153	n/a	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
154	n/a	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
155	n/a	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
156	n/a	0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
157	n/a	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
158	n/a	0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
159	n/a	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
160	n/a	0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
161	n/a	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
162	n/a	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
163	n/a	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
164	n/a	0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
165	n/a	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
166	n/a	0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
167	n/a	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
168	n/a	0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
169	n/a	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
170	n/a	0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
171	n/a	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
172	n/a	0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
173	n/a	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
174	n/a	0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
175	n/a	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
176	n/a	0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
177	n/a	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
178	n/a	0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
179	n/a	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
180	n/a	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
181	n/a	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
182	n/a	0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
183	n/a	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
184	n/a	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
185	n/a	};
186	n/a
187	n/a	/*[clinic input]
188	n/a	module binascii
189	n/a	[clinic start generated code]*/
190	n/a	/[clinic end generated code: output=da39a3ee5e6b4b0d input=de89fb46bcaf3fec]/
191	n/a
192	n/a	/*[python input]
193	n/a
194	n/a	class ascii_buffer_converter(CConverter):
195	n/a	type = 'Py_buffer'
196	n/a	converter = 'ascii_buffer_converter'
197	n/a	impl_by_reference = True
198	n/a	c_default = "{NULL, NULL}"
199	n/a
200	n/a	def cleanup(self):
201	n/a	name = self.name
202	n/a	return "".join(["if (", name, ".obj)\n PyBuffer_Release(&", name, ");\n"])
203	n/a
204	n/a	[python start generated code]*/
205	n/a	/[python end generated code: output=da39a3ee5e6b4b0d input=3eb7b63610da92cd]/
206	n/a
207	n/a	static int
208	n/a	ascii_buffer_converter(PyObject arg, Py_buffer buf)
209	n/a	{
210	n/a	if (arg == NULL) {
211	n/a	PyBuffer_Release(buf);
212	n/a	return 1;
213	n/a	}
214	n/a	if (PyUnicode_Check(arg)) {
215	n/a	if (PyUnicode_READY(arg) < 0)
216	n/a	return 0;
217	n/a	if (!PyUnicode_IS_ASCII(arg)) {
218	n/a	PyErr_SetString(PyExc_ValueError,
219	n/a	"string argument should contain only ASCII characters");
220	n/a	return 0;
221	n/a	}
222	n/a	assert(PyUnicode_KIND(arg) == PyUnicode_1BYTE_KIND);
223	n/a	buf->buf = (void *) PyUnicode_1BYTE_DATA(arg);
224	n/a	buf->len = PyUnicode_GET_LENGTH(arg);
225	n/a	buf->obj = NULL;
226	n/a	return 1;
227	n/a	}
228	n/a	if (PyObject_GetBuffer(arg, buf, PyBUF_SIMPLE) != 0) {
229	n/a	PyErr_Format(PyExc_TypeError,
230	n/a	"argument should be bytes, buffer or ASCII string, "
231	n/a	"not '%.100s'", Py_TYPE(arg)->tp_name);
232	n/a	return 0;
233	n/a	}
234	n/a	if (!PyBuffer_IsContiguous(buf, 'C')) {
235	n/a	PyErr_Format(PyExc_TypeError,
236	n/a	"argument should be a contiguous buffer, "
237	n/a	"not '%.100s'", Py_TYPE(arg)->tp_name);
238	n/a	PyBuffer_Release(buf);
239	n/a	return 0;
240	n/a	}
241	n/a	return Py_CLEANUP_SUPPORTED;
242	n/a	}
243	n/a
244	n/a	#include "clinic/binascii.c.h"
245	n/a
246	n/a	/*[clinic input]
247	n/a	binascii.a2b_uu
248	n/a
249	n/a	data: ascii_buffer
250	n/a	/
251	n/a
252	n/a	Decode a line of uuencoded data.
253	n/a	[clinic start generated code]*/
254	n/a
255	n/a	static PyObject *
256	n/a	binascii_a2b_uu_impl(PyObject module, Py_buffer data)
257	n/a	/[clinic end generated code: output=e027f8e0b0598742 input=7cafeaf73df63d1c]/
258	n/a	{
259	n/a	const unsigned char *ascii_data;
260	n/a	unsigned char *bin_data;
261	n/a	int leftbits = 0;
262	n/a	unsigned char this_ch;
263	n/a	unsigned int leftchar = 0;
264	n/a	PyObject *rv;
265	n/a	Py_ssize_t ascii_len, bin_len;
266	n/a
267	n/a	ascii_data = data->buf;
268	n/a	ascii_len = data->len;
269	n/a
270	n/a	assert(ascii_len >= 0);
271	n/a
272	n/a	/* First byte: binary data length (in bytes) */
273	n/a	bin_len = (*ascii_data++ - ' ') & 077;
274	n/a	ascii_len--;
275	n/a
276	n/a	/* Allocate the buffer */
277	n/a	if ( (rv=PyBytes_FromStringAndSize(NULL, bin_len)) == NULL )
278	n/a	return NULL;
279	n/a	bin_data = (unsigned char *)PyBytes_AS_STRING(rv);
280	n/a
281	n/a	for( ; bin_len > 0 ; ascii_len--, ascii_data++ ) {
282	n/a	/* XXX is it really best to add NULs if there's no more data */
283	n/a	this_ch = (ascii_len > 0) ? *ascii_data : 0;
284	n/a	if ( this_ch == '\n' \|\| this_ch == '\r' \|\| ascii_len <= 0) {
285	n/a	/*
286	n/a	** Whitespace. Assume some spaces got eaten at
287	n/a	** end-of-line. (We check this later)
288	n/a	*/
289	n/a	this_ch = 0;
290	n/a	} else {
291	n/a	/* Check the character for legality
292	n/a	** The 64 in stead of the expected 63 is because
293	n/a	** there are a few uuencodes out there that use
294	n/a	** '`' as zero instead of space.
295	n/a	*/
296	n/a	if ( this_ch < ' ' \|\| this_ch > (' ' + 64)) {
297	n/a	PyErr_SetString(Error, "Illegal char");
298	n/a	Py_DECREF(rv);
299	n/a	return NULL;
300	n/a	}
301	n/a	this_ch = (this_ch - ' ') & 077;
302	n/a	}
303	n/a	/*
304	n/a	** Shift it in on the low end, and see if there's
305	n/a	** a byte ready for output.
306	n/a	*/
307	n/a	leftchar = (leftchar << 6) \| (this_ch);
308	n/a	leftbits += 6;
309	n/a	if ( leftbits >= 8 ) {
310	n/a	leftbits -= 8;
311	n/a	*bin_data++ = (leftchar >> leftbits) & 0xff;
312	n/a	leftchar &= ((1 << leftbits) - 1);
313	n/a	bin_len--;
314	n/a	}
315	n/a	}
316	n/a	/*
317	n/a	** Finally, check that if there's anything left on the line
318	n/a	** that it's whitespace only.
319	n/a	*/
320	n/a	while( ascii_len-- > 0 ) {
321	n/a	this_ch = *ascii_data++;
322	n/a	/* Extra '`' may be written as padding in some cases */
323	n/a	if ( this_ch != ' ' && this_ch != ' '+64 &&
324	n/a	this_ch != '\n' && this_ch != '\r' ) {
325	n/a	PyErr_SetString(Error, "Trailing garbage");
326	n/a	Py_DECREF(rv);
327	n/a	return NULL;
328	n/a	}
329	n/a	}
330	n/a	return rv;
331	n/a	}
332	n/a
333	n/a	/*[clinic input]
334	n/a	binascii.b2a_uu
335	n/a
336	n/a	data: Py_buffer
337	n/a	/
338	n/a
339	n/a	Uuencode line of data.
340	n/a	[clinic start generated code]*/
341	n/a
342	n/a	static PyObject *
343	n/a	binascii_b2a_uu_impl(PyObject module, Py_buffer data)
344	n/a	/[clinic end generated code: output=0070670e52e4aa6b input=00fdf458ce8b465b]/
345	n/a	{
346	n/a	unsigned char *ascii_data;
347	n/a	const unsigned char *bin_data;
348	n/a	int leftbits = 0;
349	n/a	unsigned char this_ch;
350	n/a	unsigned int leftchar = 0;
351	n/a	Py_ssize_t bin_len, out_len;
352	n/a	_PyBytesWriter writer;
353	n/a
354	n/a	_PyBytesWriter_Init(&writer);
355	n/a	bin_data = data->buf;
356	n/a	bin_len = data->len;
357	n/a	if ( bin_len > 45 ) {
358	n/a	/* The 45 is a limit that appears in all uuencode's */
359	n/a	PyErr_SetString(Error, "At most 45 bytes at once");
360	n/a	return NULL;
361	n/a	}
362	n/a
363	n/a	/* We're lazy and allocate to much (fixed up later) */
364	n/a	out_len = 2 + (bin_len + 2) / 3 * 4;
365	n/a	ascii_data = _PyBytesWriter_Alloc(&writer, out_len);
366	n/a	if (ascii_data == NULL)
367	n/a	return NULL;
368	n/a
369	n/a	/* Store the length */
370	n/a	*ascii_data++ = ' ' + (bin_len & 077);
371	n/a
372	n/a	for( ; bin_len > 0 \|\| leftbits != 0 ; bin_len--, bin_data++ ) {
373	n/a	/* Shift the data (or padding) into our buffer */
374	n/a	if ( bin_len > 0 ) /* Data */
375	n/a	leftchar = (leftchar << 8) \| *bin_data;
376	n/a	else /* Padding */
377	n/a	leftchar <<= 8;
378	n/a	leftbits += 8;
379	n/a
380	n/a	/* See if there are 6-bit groups ready */
381	n/a	while ( leftbits >= 6 ) {
382	n/a	this_ch = (leftchar >> (leftbits-6)) & 0x3f;
383	n/a	leftbits -= 6;
384	n/a	*ascii_data++ = this_ch + ' ';
385	n/a	}
386	n/a	}
387	n/a	ascii_data++ = '\n'; / Append a courtesy newline */
388	n/a
389	n/a	return _PyBytesWriter_Finish(&writer, ascii_data);
390	n/a	}
391	n/a
392	n/a
393	n/a	static int
394	n/a	binascii_find_valid(const unsigned char *s, Py_ssize_t slen, int num)
395	n/a	{
396	n/a	/* Finds & returns the (num+1)th
397	n/a	** valid character for base64, or -1 if none.
398	n/a	*/
399	n/a
400	n/a	int ret = -1;
401	n/a	unsigned char c, b64val;
402	n/a
403	n/a	while ((slen > 0) && (ret == -1)) {
404	n/a	c = *s;
405	n/a	b64val = table_a2b_base64[c & 0x7f];
406	n/a	if ( ((c <= 0x7f) && (b64val != (unsigned char)-1)) ) {
407	n/a	if (num == 0)
408	n/a	ret = *s;
409	n/a	num--;
410	n/a	}
411	n/a
412	n/a	s++;
413	n/a	slen--;
414	n/a	}
415	n/a	return ret;
416	n/a	}
417	n/a
418	n/a	/*[clinic input]
419	n/a	binascii.a2b_base64
420	n/a
421	n/a	data: ascii_buffer
422	n/a	/
423	n/a
424	n/a	Decode a line of base64 data.
425	n/a	[clinic start generated code]*/
426	n/a
427	n/a	static PyObject *
428	n/a	binascii_a2b_base64_impl(PyObject module, Py_buffer data)
429	n/a	/[clinic end generated code: output=0628223f19fd3f9b input=5872acf6e1cac243]/
430	n/a	{
431	n/a	const unsigned char *ascii_data;
432	n/a	unsigned char *bin_data;
433	n/a	int leftbits = 0;
434	n/a	unsigned char this_ch;
435	n/a	unsigned int leftchar = 0;
436	n/a	Py_ssize_t ascii_len, bin_len;
437	n/a	int quad_pos = 0;
438	n/a	_PyBytesWriter writer;
439	n/a
440	n/a	ascii_data = data->buf;
441	n/a	ascii_len = data->len;
442	n/a
443	n/a	assert(ascii_len >= 0);
444	n/a
445	n/a	if (ascii_len > PY_SSIZE_T_MAX - 3)
446	n/a	return PyErr_NoMemory();
447	n/a
448	n/a	bin_len = ((ascii_len+3)/4)3; / Upper bound, corrected later */
449	n/a
450	n/a	_PyBytesWriter_Init(&writer);
451	n/a
452	n/a	/* Allocate the buffer */
453	n/a	bin_data = _PyBytesWriter_Alloc(&writer, bin_len);
454	n/a	if (bin_data == NULL)
455	n/a	return NULL;
456	n/a
457	n/a	for( ; ascii_len > 0; ascii_len--, ascii_data++) {
458	n/a	this_ch = *ascii_data;
459	n/a
460	n/a	if (this_ch > 0x7f \|\|
461	n/a	this_ch == '\r' \|\| this_ch == '\n' \|\| this_ch == ' ')
462	n/a	continue;
463	n/a
464	n/a	/* Check for pad sequences and ignore
465	n/a	** the invalid ones.
466	n/a	*/
467	n/a	if (this_ch == BASE64_PAD) {
468	n/a	if ( (quad_pos < 2) \|\|
469	n/a	((quad_pos == 2) &&
470	n/a	(binascii_find_valid(ascii_data, ascii_len, 1)
471	n/a	!= BASE64_PAD)) )
472	n/a	{
473	n/a	continue;
474	n/a	}
475	n/a	else {
476	n/a	/* A pad sequence means no more input.
477	n/a	** We've already interpreted the data
478	n/a	** from the quad at this point.
479	n/a	*/
480	n/a	leftbits = 0;
481	n/a	break;
482	n/a	}
483	n/a	}
484	n/a
485	n/a	this_ch = table_a2b_base64[*ascii_data];
486	n/a	if ( this_ch == (unsigned char) -1 )
487	n/a	continue;
488	n/a
489	n/a	/*
490	n/a	** Shift it in on the low end, and see if there's
491	n/a	** a byte ready for output.
492	n/a	*/
493	n/a	quad_pos = (quad_pos + 1) & 0x03;
494	n/a	leftchar = (leftchar << 6) \| (this_ch);
495	n/a	leftbits += 6;
496	n/a
497	n/a	if ( leftbits >= 8 ) {
498	n/a	leftbits -= 8;
499	n/a	*bin_data++ = (leftchar >> leftbits) & 0xff;
500	n/a	leftchar &= ((1 << leftbits) - 1);
501	n/a	}
502	n/a	}
503	n/a
504	n/a	if (leftbits != 0) {
505	n/a	PyErr_SetString(Error, "Incorrect padding");
506	n/a	_PyBytesWriter_Dealloc(&writer);
507	n/a	return NULL;
508	n/a	}
509	n/a
510	n/a	return _PyBytesWriter_Finish(&writer, bin_data);
511	n/a	}
512	n/a
513	n/a
514	n/a	/*[clinic input]
515	n/a	binascii.b2a_base64
516	n/a
517	n/a	data: Py_buffer
518	n/a	*
519	n/a	newline: int(c_default="1") = True
520	n/a
521	n/a	Base64-code line of data.
522	n/a	[clinic start generated code]*/
523	n/a
524	n/a	static PyObject *
525	n/a	binascii_b2a_base64_impl(PyObject module, Py_buffer data, int newline)
526	n/a	/[clinic end generated code: output=4ad62c8e8485d3b3 input=7b2ea6fa38d8924c]/
527	n/a	{
528	n/a	unsigned char *ascii_data;
529	n/a	const unsigned char *bin_data;
530	n/a	int leftbits = 0;
531	n/a	unsigned char this_ch;
532	n/a	unsigned int leftchar = 0;
533	n/a	Py_ssize_t bin_len, out_len;
534	n/a	_PyBytesWriter writer;
535	n/a
536	n/a	bin_data = data->buf;
537	n/a	bin_len = data->len;
538	n/a	_PyBytesWriter_Init(&writer);
539	n/a
540	n/a	assert(bin_len >= 0);
541	n/a
542	n/a	if ( bin_len > BASE64_MAXBIN ) {
543	n/a	PyErr_SetString(Error, "Too much data for base64 line");
544	n/a	return NULL;
545	n/a	}
546	n/a
547	n/a	/* We're lazy and allocate too much (fixed up later).
548	n/a	"+2" leaves room for up to two pad characters.
549	n/a	Note that 'b' gets encoded as 'Yg==\n' (1 in, 5 out). */
550	n/a	out_len = bin_len*2 + 2;
551	n/a	if (newline)
552	n/a	out_len++;
553	n/a	ascii_data = _PyBytesWriter_Alloc(&writer, out_len);
554	n/a	if (ascii_data == NULL)
555	n/a	return NULL;
556	n/a
557	n/a	for( ; bin_len > 0 ; bin_len--, bin_data++ ) {
558	n/a	/* Shift the data into our buffer */
559	n/a	leftchar = (leftchar << 8) \| *bin_data;
560	n/a	leftbits += 8;
561	n/a
562	n/a	/* See if there are 6-bit groups ready */
563	n/a	while ( leftbits >= 6 ) {
564	n/a	this_ch = (leftchar >> (leftbits-6)) & 0x3f;
565	n/a	leftbits -= 6;
566	n/a	*ascii_data++ = table_b2a_base64[this_ch];
567	n/a	}
568	n/a	}
569	n/a	if ( leftbits == 2 ) {
570	n/a	*ascii_data++ = table_b2a_base64[(leftchar&3) << 4];
571	n/a	*ascii_data++ = BASE64_PAD;
572	n/a	*ascii_data++ = BASE64_PAD;
573	n/a	} else if ( leftbits == 4 ) {
574	n/a	*ascii_data++ = table_b2a_base64[(leftchar&0xf) << 2];
575	n/a	*ascii_data++ = BASE64_PAD;
576	n/a	}
577	n/a	if (newline)
578	n/a	ascii_data++ = '\n'; / Append a courtesy newline */
579	n/a
580	n/a	return _PyBytesWriter_Finish(&writer, ascii_data);
581	n/a	}
582	n/a
583	n/a	/*[clinic input]
584	n/a	binascii.a2b_hqx
585	n/a
586	n/a	data: ascii_buffer
587	n/a	/
588	n/a
589	n/a	Decode .hqx coding.
590	n/a	[clinic start generated code]*/
591	n/a
592	n/a	static PyObject *
593	n/a	binascii_a2b_hqx_impl(PyObject module, Py_buffer data)
594	n/a	/[clinic end generated code: output=4d6d8c54d54ea1c1 input=0d914c680e0eed55]/
595	n/a	{
596	n/a	const unsigned char *ascii_data;
597	n/a	unsigned char *bin_data;
598	n/a	int leftbits = 0;
599	n/a	unsigned char this_ch;
600	n/a	unsigned int leftchar = 0;
601	n/a	PyObject *res;
602	n/a	Py_ssize_t len;
603	n/a	int done = 0;
604	n/a	_PyBytesWriter writer;
605	n/a
606	n/a	ascii_data = data->buf;
607	n/a	len = data->len;
608	n/a	_PyBytesWriter_Init(&writer);
609	n/a
610	n/a	assert(len >= 0);
611	n/a
612	n/a	if (len > PY_SSIZE_T_MAX - 2)
613	n/a	return PyErr_NoMemory();
614	n/a
615	n/a	/* Allocate a string that is too big (fixed later)
616	n/a	Add two to the initial length to prevent interning which
617	n/a	would preclude subsequent resizing. */
618	n/a	bin_data = _PyBytesWriter_Alloc(&writer, len + 2);
619	n/a	if (bin_data == NULL)
620	n/a	return NULL;
621	n/a
622	n/a	for( ; len > 0 ; len--, ascii_data++ ) {
623	n/a	/* Get the byte and look it up */
624	n/a	this_ch = table_a2b_hqx[*ascii_data];
625	n/a	if ( this_ch == SKIP )
626	n/a	continue;
627	n/a	if ( this_ch == FAIL ) {
628	n/a	PyErr_SetString(Error, "Illegal char");
629	n/a	_PyBytesWriter_Dealloc(&writer);
630	n/a	return NULL;
631	n/a	}
632	n/a	if ( this_ch == DONE ) {
633	n/a	/* The terminating colon */
634	n/a	done = 1;
635	n/a	break;
636	n/a	}
637	n/a
638	n/a	/* Shift it into the buffer and see if any bytes are ready */
639	n/a	leftchar = (leftchar << 6) \| (this_ch);
640	n/a	leftbits += 6;
641	n/a	if ( leftbits >= 8 ) {
642	n/a	leftbits -= 8;
643	n/a	*bin_data++ = (leftchar >> leftbits) & 0xff;
644	n/a	leftchar &= ((1 << leftbits) - 1);
645	n/a	}
646	n/a	}
647	n/a
648	n/a	if ( leftbits && !done ) {
649	n/a	PyErr_SetString(Incomplete,
650	n/a	"String has incomplete number of bytes");
651	n/a	_PyBytesWriter_Dealloc(&writer);
652	n/a	return NULL;
653	n/a	}
654	n/a
655	n/a	res = _PyBytesWriter_Finish(&writer, bin_data);
656	n/a	if (res == NULL)
657	n/a	return NULL;
658	n/a	return Py_BuildValue("Ni", res, done);
659	n/a	}
660	n/a
661	n/a
662	n/a	/*[clinic input]
663	n/a	binascii.rlecode_hqx
664	n/a
665	n/a	data: Py_buffer
666	n/a	/
667	n/a
668	n/a	Binhex RLE-code binary data.
669	n/a	[clinic start generated code]*/
670	n/a
671	n/a	static PyObject *
672	n/a	binascii_rlecode_hqx_impl(PyObject module, Py_buffer data)
673	n/a	/[clinic end generated code: output=393d79338f5f5629 input=e1f1712447a82b09]/
674	n/a	{
675	n/a	const unsigned char *in_data;
676	n/a	unsigned char *out_data;
677	n/a	unsigned char ch;
678	n/a	Py_ssize_t in, inend, len;
679	n/a	_PyBytesWriter writer;
680	n/a
681	n/a	_PyBytesWriter_Init(&writer);
682	n/a	in_data = data->buf;
683	n/a	len = data->len;
684	n/a
685	n/a	assert(len >= 0);
686	n/a
687	n/a	if (len > PY_SSIZE_T_MAX / 2 - 2)
688	n/a	return PyErr_NoMemory();
689	n/a
690	n/a	/* Worst case: output is twice as big as input (fixed later) */
691	n/a	out_data = _PyBytesWriter_Alloc(&writer, len * 2 + 2);
692	n/a	if (out_data == NULL)
693	n/a	return NULL;
694	n/a
695	n/a	for( in=0; in<len; in++) {
696	n/a	ch = in_data[in];
697	n/a	if ( ch == RUNCHAR ) {
698	n/a	/* RUNCHAR. Escape it. */
699	n/a	*out_data++ = RUNCHAR;
700	n/a	*out_data++ = 0;
701	n/a	} else {
702	n/a	/* Check how many following are the same */
703	n/a	for(inend=in+1;
704	n/a	inend<len && in_data[inend] == ch &&
705	n/a	inend < in+255;
706	n/a	inend++) ;
707	n/a	if ( inend - in > 3 ) {
708	n/a	/* More than 3 in a row. Output RLE. */
709	n/a	*out_data++ = ch;
710	n/a	*out_data++ = RUNCHAR;
711	n/a	*out_data++ = (unsigned char) (inend-in);
712	n/a	in = inend-1;
713	n/a	} else {
714	n/a	/* Less than 3. Output the byte itself */
715	n/a	*out_data++ = ch;
716	n/a	}
717	n/a	}
718	n/a	}
719	n/a
720	n/a	return _PyBytesWriter_Finish(&writer, out_data);
721	n/a	}
722	n/a
723	n/a
724	n/a	/*[clinic input]
725	n/a	binascii.b2a_hqx
726	n/a
727	n/a	data: Py_buffer
728	n/a	/
729	n/a
730	n/a	Encode .hqx data.
731	n/a	[clinic start generated code]*/
732	n/a
733	n/a	static PyObject *
734	n/a	binascii_b2a_hqx_impl(PyObject module, Py_buffer data)
735	n/a	/[clinic end generated code: output=d0aa5a704bc9f7de input=9596ebe019fe12ba]/
736	n/a	{
737	n/a	unsigned char *ascii_data;
738	n/a	const unsigned char *bin_data;
739	n/a	int leftbits = 0;
740	n/a	unsigned char this_ch;
741	n/a	unsigned int leftchar = 0;
742	n/a	Py_ssize_t len;
743	n/a	_PyBytesWriter writer;
744	n/a
745	n/a	bin_data = data->buf;
746	n/a	len = data->len;
747	n/a	_PyBytesWriter_Init(&writer);
748	n/a
749	n/a	assert(len >= 0);
750	n/a
751	n/a	if (len > PY_SSIZE_T_MAX / 2 - 2)
752	n/a	return PyErr_NoMemory();
753	n/a
754	n/a	/* Allocate a buffer that is at least large enough */
755	n/a	ascii_data = _PyBytesWriter_Alloc(&writer, len * 2 + 2);
756	n/a	if (ascii_data == NULL)
757	n/a	return NULL;
758	n/a
759	n/a	for( ; len > 0 ; len--, bin_data++ ) {
760	n/a	/* Shift into our buffer, and output any 6bits ready */
761	n/a	leftchar = (leftchar << 8) \| *bin_data;
762	n/a	leftbits += 8;
763	n/a	while ( leftbits >= 6 ) {
764	n/a	this_ch = (leftchar >> (leftbits-6)) & 0x3f;
765	n/a	leftbits -= 6;
766	n/a	*ascii_data++ = table_b2a_hqx[this_ch];
767	n/a	}
768	n/a	}
769	n/a	/* Output a possible runt byte */
770	n/a	if ( leftbits ) {
771	n/a	leftchar <<= (6-leftbits);
772	n/a	*ascii_data++ = table_b2a_hqx[leftchar & 0x3f];
773	n/a	}
774	n/a
775	n/a	return _PyBytesWriter_Finish(&writer, ascii_data);
776	n/a	}
777	n/a
778	n/a
779	n/a	/*[clinic input]
780	n/a	binascii.rledecode_hqx
781	n/a
782	n/a	data: Py_buffer
783	n/a	/
784	n/a
785	n/a	Decode hexbin RLE-coded string.
786	n/a	[clinic start generated code]*/
787	n/a
788	n/a	static PyObject *
789	n/a	binascii_rledecode_hqx_impl(PyObject module, Py_buffer data)
790	n/a	/[clinic end generated code: output=9826619565de1c6c input=54cdd49fc014402c]/
791	n/a	{
792	n/a	const unsigned char *in_data;
793	n/a	unsigned char *out_data;
794	n/a	unsigned char in_byte, in_repeat;
795	n/a	Py_ssize_t in_len;
796	n/a	_PyBytesWriter writer;
797	n/a
798	n/a	in_data = data->buf;
799	n/a	in_len = data->len;
800	n/a	_PyBytesWriter_Init(&writer);
801	n/a
802	n/a	assert(in_len >= 0);
803	n/a
804	n/a	/* Empty string is a special case */
805	n/a	if ( in_len == 0 )
806	n/a	return PyBytes_FromStringAndSize("", 0);
807	n/a	else if (in_len > PY_SSIZE_T_MAX / 2)
808	n/a	return PyErr_NoMemory();
809	n/a
810	n/a	/* Allocate a buffer of reasonable size. Resized when needed */
811	n/a	out_data = _PyBytesWriter_Alloc(&writer, in_len);
812	n/a	if (out_data == NULL)
813	n/a	return NULL;
814	n/a
815	n/a	/* Use overallocation */
816	n/a	writer.overallocate = 1;
817	n/a
818	n/a	/*
819	n/a	** We need two macros here to get/put bytes and handle
820	n/a	** end-of-buffer for input and output strings.
821	n/a	*/
822	n/a	#define INBYTE(b) \
823	n/a	do { \
824	n/a	if ( --in_len < 0 ) { \
825	n/a	PyErr_SetString(Incomplete, ""); \
826	n/a	goto error; \
827	n/a	} \
828	n/a	b = *in_data++; \
829	n/a	} while(0)
830	n/a
831	n/a	/*
832	n/a	** Handle first byte separately (since we have to get angry
833	n/a	** in case of an orphaned RLE code).
834	n/a	*/
835	n/a	INBYTE(in_byte);
836	n/a
837	n/a	if (in_byte == RUNCHAR) {
838	n/a	INBYTE(in_repeat);
839	n/a	/* only 1 byte will be written, but 2 bytes were preallocated:
840	n/a	subtract 1 byte to prevent overallocation */
841	n/a	writer.min_size--;
842	n/a
843	n/a	if (in_repeat != 0) {
844	n/a	/* Note Error, not Incomplete (which is at the end
845	n/a	** of the string only). This is a programmer error.
846	n/a	*/
847	n/a	PyErr_SetString(Error, "Orphaned RLE code at start");
848	n/a	goto error;
849	n/a	}
850	n/a	*out_data++ = RUNCHAR;
851	n/a	} else {
852	n/a	*out_data++ = in_byte;
853	n/a	}
854	n/a
855	n/a	while( in_len > 0 ) {
856	n/a	INBYTE(in_byte);
857	n/a
858	n/a	if (in_byte == RUNCHAR) {
859	n/a	INBYTE(in_repeat);
860	n/a	/* only 1 byte will be written, but 2 bytes were preallocated:
861	n/a	subtract 1 byte to prevent overallocation */
862	n/a	writer.min_size--;
863	n/a
864	n/a	if ( in_repeat == 0 ) {
865	n/a	/* Just an escaped RUNCHAR value */
866	n/a	*out_data++ = RUNCHAR;
867	n/a	} else {
868	n/a	/* Pick up value and output a sequence of it */
869	n/a	in_byte = out_data[-1];
870	n/a
871	n/a	/* enlarge the buffer if needed */
872	n/a	if (in_repeat > 1) {
873	n/a	/* -1 because we already preallocated 1 byte */
874	n/a	out_data = _PyBytesWriter_Prepare(&writer, out_data,
875	n/a	in_repeat - 1);
876	n/a	if (out_data == NULL)
877	n/a	goto error;
878	n/a	}
879	n/a
880	n/a	while ( --in_repeat > 0 )
881	n/a	*out_data++ = in_byte;
882	n/a	}
883	n/a	} else {
884	n/a	/* Normal byte */
885	n/a	*out_data++ = in_byte;
886	n/a	}
887	n/a	}
888	n/a	return _PyBytesWriter_Finish(&writer, out_data);
889	n/a
890	n/a	error:
891	n/a	_PyBytesWriter_Dealloc(&writer);
892	n/a	return NULL;
893	n/a	}
894	n/a
895	n/a
896	n/a	/*[clinic input]
897	n/a	binascii.crc_hqx -> unsigned_int
898	n/a
899	n/a	data: Py_buffer
900	n/a	crc: unsigned_int(bitwise=True)
901	n/a	/
902	n/a
903	n/a	Compute CRC-CCITT incrementally.
904	n/a	[clinic start generated code]*/
905	n/a
906	n/a	static unsigned int
907	n/a	binascii_crc_hqx_impl(PyObject module, Py_buffer data, unsigned int crc)
908	n/a	/[clinic end generated code: output=8ec2a78590d19170 input=f18240ff8c705b79]/
909	n/a	{
910	n/a	const unsigned char *bin_data;
911	n/a	Py_ssize_t len;
912	n/a
913	n/a	crc &= 0xffff;
914	n/a	bin_data = data->buf;
915	n/a	len = data->len;
916	n/a
917	n/a	while(len-- > 0) {
918	n/a	crc = ((crc<<8)&0xff00) ^ crctab_hqx[(crc>>8)^*bin_data++];
919	n/a	}
920	n/a
921	n/a	return crc;
922	n/a	}
923	n/a
924	n/a	#ifndef USE_ZLIB_CRC32
925	n/a	/* Crc - 32 BIT ANSI X3.66 CRC checksum files
926	n/a	Also known as: ISO 3307
927	n/a	**********************************************************************\|
928	n/a	* *\|
929	n/a	* Demonstration program to compute the 32-bit CRC used as the frame *\|
930	n/a	* check sequence in ADCCP (ANSI X3.66, also known as FIPS PUB 71 *\|
931	n/a	* and FED-STD-1003, the U.S. versions of CCITT's X.25 link-level *\|
932	n/a	* protocol). The 32-bit FCS was added via the Federal Register, *\|
933	n/a	* 1 June 1982, p.23798. I presume but don't know for certain that *\|
934	n/a	* this polynomial is or will be included in CCITT V.41, which *\|
935	n/a	* defines the 16-bit CRC (often called CRC-CCITT) polynomial. FIPS *\|
936	n/a	* PUB 78 says that the 32-bit FCS reduces otherwise undetected *\|
937	n/a	* errors by a factor of 10^-5 over 16-bit FCS. *\|
938	n/a	* *\|
939	n/a	**********************************************************************\|
940	n/a
941	n/a	Copyright (C) 1986 Gary S. Brown. You may use this program, or
942	n/a	code or tables extracted from it, as desired without restriction.
943	n/a
944	n/a	First, the polynomial itself and its table of feedback terms. The
945	n/a	polynomial is
946	n/a	X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0
947	n/a	Note that we take it "backwards" and put the highest-order term in
948	n/a	the lowest-order bit. The X^32 term is "implied"; the LSB is the
949	n/a	X^31 term, etc. The X^0 term (usually shown as "+1") results in
950	n/a	the MSB being 1.
951	n/a
952	n/a	Note that the usual hardware shift register implementation, which
953	n/a	is what we're using (we're merely optimizing it by doing eight-bit
954	n/a	chunks at a time) shifts bits into the lowest-order term. In our
955	n/a	implementation, that means shifting towards the right. Why do we
956	n/a	do it this way? Because the calculated CRC must be transmitted in
957	n/a	order from highest-order term to lowest-order term. UARTs transmit
958	n/a	characters in order from LSB to MSB. By storing the CRC this way,
959	n/a	we hand it to the UART in the order low-byte to high-byte; the UART
960	n/a	sends each low-bit to hight-bit; and the result is transmission bit
961	n/a	by bit from highest- to lowest-order term without requiring any bit
962	n/a	shuffling on our part. Reception works similarly.
963	n/a
964	n/a	The feedback terms table consists of 256, 32-bit entries. Notes:
965	n/a
966	n/a	1. The table can be generated at runtime if desired; code to do so
967	n/a	is shown later. It might not be obvious, but the feedback
968	n/a	terms simply represent the results of eight shift/xor opera-
969	n/a	tions for all combinations of data and CRC register values.
970	n/a
971	n/a	2. The CRC accumulation logic is the same for all CRC polynomials,
972	n/a	be they sixteen or thirty-two bits wide. You simply choose the
973	n/a	appropriate table. Alternatively, because the table can be
974	n/a	generated at runtime, you can start by generating the table for
975	n/a	the polynomial in question and use exactly the same "updcrc",
976	n/a	if your application needn't simultaneously handle two CRC
977	n/a	polynomials. (Note, however, that XMODEM is strange.)
978	n/a
979	n/a	3. For 16-bit CRCs, the table entries need be only 16 bits wide;
980	n/a	of course, 32-bit entries work OK if the high 16 bits are zero.
981	n/a
982	n/a	4. The values must be right-shifted by eight bits by the "updcrc"
983	n/a	logic; the shift must be unsigned (bring in zeroes). On some
984	n/a	hardware you could probably optimize the shift in assembler by
985	n/a	using byte-swap instructions.
986	n/a	********************************************************************/
987	n/a
988	n/a	static const unsigned int crc_32_tab[256] = {
989	n/a	0x00000000U, 0x77073096U, 0xee0e612cU, 0x990951baU, 0x076dc419U,
990	n/a	0x706af48fU, 0xe963a535U, 0x9e6495a3U, 0x0edb8832U, 0x79dcb8a4U,
991	n/a	0xe0d5e91eU, 0x97d2d988U, 0x09b64c2bU, 0x7eb17cbdU, 0xe7b82d07U,
992	n/a	0x90bf1d91U, 0x1db71064U, 0x6ab020f2U, 0xf3b97148U, 0x84be41deU,
993	n/a	0x1adad47dU, 0x6ddde4ebU, 0xf4d4b551U, 0x83d385c7U, 0x136c9856U,
994	n/a	0x646ba8c0U, 0xfd62f97aU, 0x8a65c9ecU, 0x14015c4fU, 0x63066cd9U,
995	n/a	0xfa0f3d63U, 0x8d080df5U, 0x3b6e20c8U, 0x4c69105eU, 0xd56041e4U,
996	n/a	0xa2677172U, 0x3c03e4d1U, 0x4b04d447U, 0xd20d85fdU, 0xa50ab56bU,
997	n/a	0x35b5a8faU, 0x42b2986cU, 0xdbbbc9d6U, 0xacbcf940U, 0x32d86ce3U,
998	n/a	0x45df5c75U, 0xdcd60dcfU, 0xabd13d59U, 0x26d930acU, 0x51de003aU,
999	n/a	0xc8d75180U, 0xbfd06116U, 0x21b4f4b5U, 0x56b3c423U, 0xcfba9599U,
1000	n/a	0xb8bda50fU, 0x2802b89eU, 0x5f058808U, 0xc60cd9b2U, 0xb10be924U,
1001	n/a	0x2f6f7c87U, 0x58684c11U, 0xc1611dabU, 0xb6662d3dU, 0x76dc4190U,
1002	n/a	0x01db7106U, 0x98d220bcU, 0xefd5102aU, 0x71b18589U, 0x06b6b51fU,
1003	n/a	0x9fbfe4a5U, 0xe8b8d433U, 0x7807c9a2U, 0x0f00f934U, 0x9609a88eU,
1004	n/a	0xe10e9818U, 0x7f6a0dbbU, 0x086d3d2dU, 0x91646c97U, 0xe6635c01U,
1005	n/a	0x6b6b51f4U, 0x1c6c6162U, 0x856530d8U, 0xf262004eU, 0x6c0695edU,
1006	n/a	0x1b01a57bU, 0x8208f4c1U, 0xf50fc457U, 0x65b0d9c6U, 0x12b7e950U,
1007	n/a	0x8bbeb8eaU, 0xfcb9887cU, 0x62dd1ddfU, 0x15da2d49U, 0x8cd37cf3U,
1008	n/a	0xfbd44c65U, 0x4db26158U, 0x3ab551ceU, 0xa3bc0074U, 0xd4bb30e2U,
1009	n/a	0x4adfa541U, 0x3dd895d7U, 0xa4d1c46dU, 0xd3d6f4fbU, 0x4369e96aU,
1010	n/a	0x346ed9fcU, 0xad678846U, 0xda60b8d0U, 0x44042d73U, 0x33031de5U,
1011	n/a	0xaa0a4c5fU, 0xdd0d7cc9U, 0x5005713cU, 0x270241aaU, 0xbe0b1010U,
1012	n/a	0xc90c2086U, 0x5768b525U, 0x206f85b3U, 0xb966d409U, 0xce61e49fU,
1013	n/a	0x5edef90eU, 0x29d9c998U, 0xb0d09822U, 0xc7d7a8b4U, 0x59b33d17U,
1014	n/a	0x2eb40d81U, 0xb7bd5c3bU, 0xc0ba6cadU, 0xedb88320U, 0x9abfb3b6U,
1015	n/a	0x03b6e20cU, 0x74b1d29aU, 0xead54739U, 0x9dd277afU, 0x04db2615U,
1016	n/a	0x73dc1683U, 0xe3630b12U, 0x94643b84U, 0x0d6d6a3eU, 0x7a6a5aa8U,
1017	n/a	0xe40ecf0bU, 0x9309ff9dU, 0x0a00ae27U, 0x7d079eb1U, 0xf00f9344U,
1018	n/a	0x8708a3d2U, 0x1e01f268U, 0x6906c2feU, 0xf762575dU, 0x806567cbU,
1019	n/a	0x196c3671U, 0x6e6b06e7U, 0xfed41b76U, 0x89d32be0U, 0x10da7a5aU,
1020	n/a	0x67dd4accU, 0xf9b9df6fU, 0x8ebeeff9U, 0x17b7be43U, 0x60b08ed5U,
1021	n/a	0xd6d6a3e8U, 0xa1d1937eU, 0x38d8c2c4U, 0x4fdff252U, 0xd1bb67f1U,
1022	n/a	0xa6bc5767U, 0x3fb506ddU, 0x48b2364bU, 0xd80d2bdaU, 0xaf0a1b4cU,
1023	n/a	0x36034af6U, 0x41047a60U, 0xdf60efc3U, 0xa867df55U, 0x316e8eefU,
1024	n/a	0x4669be79U, 0xcb61b38cU, 0xbc66831aU, 0x256fd2a0U, 0x5268e236U,
1025	n/a	0xcc0c7795U, 0xbb0b4703U, 0x220216b9U, 0x5505262fU, 0xc5ba3bbeU,
1026	n/a	0xb2bd0b28U, 0x2bb45a92U, 0x5cb36a04U, 0xc2d7ffa7U, 0xb5d0cf31U,
1027	n/a	0x2cd99e8bU, 0x5bdeae1dU, 0x9b64c2b0U, 0xec63f226U, 0x756aa39cU,
1028	n/a	0x026d930aU, 0x9c0906a9U, 0xeb0e363fU, 0x72076785U, 0x05005713U,
1029	n/a	0x95bf4a82U, 0xe2b87a14U, 0x7bb12baeU, 0x0cb61b38U, 0x92d28e9bU,
1030	n/a	0xe5d5be0dU, 0x7cdcefb7U, 0x0bdbdf21U, 0x86d3d2d4U, 0xf1d4e242U,
1031	n/a	0x68ddb3f8U, 0x1fda836eU, 0x81be16cdU, 0xf6b9265bU, 0x6fb077e1U,
1032	n/a	0x18b74777U, 0x88085ae6U, 0xff0f6a70U, 0x66063bcaU, 0x11010b5cU,
1033	n/a	0x8f659effU, 0xf862ae69U, 0x616bffd3U, 0x166ccf45U, 0xa00ae278U,
1034	n/a	0xd70dd2eeU, 0x4e048354U, 0x3903b3c2U, 0xa7672661U, 0xd06016f7U,
1035	n/a	0x4969474dU, 0x3e6e77dbU, 0xaed16a4aU, 0xd9d65adcU, 0x40df0b66U,
1036	n/a	0x37d83bf0U, 0xa9bcae53U, 0xdebb9ec5U, 0x47b2cf7fU, 0x30b5ffe9U,
1037	n/a	0xbdbdf21cU, 0xcabac28aU, 0x53b39330U, 0x24b4a3a6U, 0xbad03605U,
1038	n/a	0xcdd70693U, 0x54de5729U, 0x23d967bfU, 0xb3667a2eU, 0xc4614ab8U,
1039	n/a	0x5d681b02U, 0x2a6f2b94U, 0xb40bbe37U, 0xc30c8ea1U, 0x5a05df1bU,
1040	n/a	0x2d02ef8dU
1041	n/a	};
1042	n/a	#endif /* USE_ZLIB_CRC32 */
1043	n/a
1044	n/a	/*[clinic input]
1045	n/a	binascii.crc32 -> unsigned_int
1046	n/a
1047	n/a	data: Py_buffer
1048	n/a	crc: unsigned_int(bitwise=True) = 0
1049	n/a	/
1050	n/a
1051	n/a	Compute CRC-32 incrementally.
1052	n/a	[clinic start generated code]*/
1053	n/a
1054	n/a	static unsigned int
1055	n/a	binascii_crc32_impl(PyObject module, Py_buffer data, unsigned int crc)
1056	n/a	/[clinic end generated code: output=52cf59056a78593b input=bbe340bc99d25aa8]/
1057	n/a
1058	n/a	#ifdef USE_ZLIB_CRC32
1059	n/a	/* This was taken from zlibmodule.c PyZlib_crc32 (but is PY_SSIZE_T_CLEAN) */
1060	n/a	{
1061	n/a	const Byte *buf;
1062	n/a	Py_ssize_t len;
1063	n/a	int signed_val;
1064	n/a
1065	n/a	buf = (Byte*)data->buf;
1066	n/a	len = data->len;
1067	n/a	signed_val = crc32(crc, buf, len);
1068	n/a	return (unsigned int)signed_val & 0xffffffffU;
1069	n/a	}
1070	n/a	#else /* USE_ZLIB_CRC32 */
1071	n/a	{ /* By Jim Ahlstrom; All rights transferred to CNRI */
1072	n/a	const unsigned char *bin_data;
1073	n/a	Py_ssize_t len;
1074	n/a	unsigned int result;
1075	n/a
1076	n/a	bin_data = data->buf;
1077	n/a	len = data->len;
1078	n/a
1079	n/a	crc = ~ crc;
1080	n/a	while (len-- > 0) {
1081	n/a	crc = crc_32_tab[(crc ^ *bin_data++) & 0xff] ^ (crc >> 8);
1082	n/a	/* Note: (crc >> 8) MUST zero fill on left */
1083	n/a	}
1084	n/a
1085	n/a	result = (crc ^ 0xFFFFFFFF);
1086	n/a	return result & 0xffffffff;
1087	n/a	}
1088	n/a	#endif /* USE_ZLIB_CRC32 */
1089	n/a
1090	n/a	/*[clinic input]
1091	n/a	binascii.b2a_hex
1092	n/a
1093	n/a	data: Py_buffer
1094	n/a	/
1095	n/a
1096	n/a	Hexadecimal representation of binary data.
1097	n/a
1098	n/a	The return value is a bytes object. This function is also
1099	n/a	available as "hexlify()".
1100	n/a	[clinic start generated code]*/
1101	n/a
1102	n/a	static PyObject *
1103	n/a	binascii_b2a_hex_impl(PyObject module, Py_buffer data)
1104	n/a	/[clinic end generated code: output=92fec1a95c9897a0 input=96423cfa299ff3b1]/
1105	n/a	{
1106	n/a	return _Py_strhex_bytes((const char *)data->buf, data->len);
1107	n/a	}
1108	n/a
1109	n/a	/*[clinic input]
1110	n/a	binascii.hexlify = binascii.b2a_hex
1111	n/a
1112	n/a	Hexadecimal representation of binary data.
1113	n/a
1114	n/a	The return value is a bytes object.
1115	n/a	[clinic start generated code]*/
1116	n/a
1117	n/a	static PyObject *
1118	n/a	binascii_hexlify_impl(PyObject module, Py_buffer data)
1119	n/a	/[clinic end generated code: output=749e95e53c14880c input=2e3afae7f083f061]/
1120	n/a	{
1121	n/a	return _Py_strhex_bytes((const char *)data->buf, data->len);
1122	n/a	}
1123	n/a
1124	n/a	static int
1125	n/a	to_int(int c)
1126	n/a	{
1127	n/a	if (Py_ISDIGIT(c))
1128	n/a	return c - '0';
1129	n/a	else {
1130	n/a	if (Py_ISUPPER(c))
1131	n/a	c = Py_TOLOWER(c);
1132	n/a	if (c >= 'a' && c <= 'f')
1133	n/a	return c - 'a' + 10;
1134	n/a	}
1135	n/a	return -1;
1136	n/a	}
1137	n/a
1138	n/a
1139	n/a	/*[clinic input]
1140	n/a	binascii.a2b_hex
1141	n/a
1142	n/a	hexstr: ascii_buffer
1143	n/a	/
1144	n/a
1145	n/a	Binary data of hexadecimal representation.
1146	n/a
1147	n/a	hexstr must contain an even number of hex digits (upper or lower case).
1148	n/a	This function is also available as "unhexlify()".
1149	n/a	[clinic start generated code]*/
1150	n/a
1151	n/a	static PyObject *
1152	n/a	binascii_a2b_hex_impl(PyObject module, Py_buffer hexstr)
1153	n/a	/[clinic end generated code: output=0cc1a139af0eeecb input=9e1e7f2f94db24fd]/
1154	n/a	{
1155	n/a	const char* argbuf;
1156	n/a	Py_ssize_t arglen;
1157	n/a	PyObject *retval;
1158	n/a	char* retbuf;
1159	n/a	Py_ssize_t i, j;
1160	n/a
1161	n/a	argbuf = hexstr->buf;
1162	n/a	arglen = hexstr->len;
1163	n/a
1164	n/a	assert(arglen >= 0);
1165	n/a
1166	n/a	/* XXX What should we do about strings with an odd length? Should
1167	n/a	* we add an implicit leading zero, or a trailing zero? For now,
1168	n/a	* raise an exception.
1169	n/a	*/
1170	n/a	if (arglen % 2) {
1171	n/a	PyErr_SetString(Error, "Odd-length string");
1172	n/a	return NULL;
1173	n/a	}
1174	n/a
1175	n/a	retval = PyBytes_FromStringAndSize(NULL, (arglen/2));
1176	n/a	if (!retval)
1177	n/a	return NULL;
1178	n/a	retbuf = PyBytes_AS_STRING(retval);
1179	n/a
1180	n/a	for (i=j=0; i < arglen; i += 2) {
1181	n/a	int top = to_int(Py_CHARMASK(argbuf[i]));
1182	n/a	int bot = to_int(Py_CHARMASK(argbuf[i+1]));
1183	n/a	if (top == -1 \|\| bot == -1) {
1184	n/a	PyErr_SetString(Error,
1185	n/a	"Non-hexadecimal digit found");
1186	n/a	goto finally;
1187	n/a	}
1188	n/a	retbuf[j++] = (top << 4) + bot;
1189	n/a	}
1190	n/a	return retval;
1191	n/a
1192	n/a	finally:
1193	n/a	Py_DECREF(retval);
1194	n/a	return NULL;
1195	n/a	}
1196	n/a
1197	n/a	/*[clinic input]
1198	n/a	binascii.unhexlify = binascii.a2b_hex
1199	n/a
1200	n/a	Binary data of hexadecimal representation.
1201	n/a
1202	n/a	hexstr must contain an even number of hex digits (upper or lower case).
1203	n/a	[clinic start generated code]*/
1204	n/a
1205	n/a	static PyObject *
1206	n/a	binascii_unhexlify_impl(PyObject module, Py_buffer hexstr)
1207	n/a	/[clinic end generated code: output=51a64c06c79629e3 input=dd8c012725f462da]/
1208	n/a	{
1209	n/a	return binascii_a2b_hex_impl(module, hexstr);
1210	n/a	}
1211	n/a
1212	n/a	static const int table_hex[128] = {
1213	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1214	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1215	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1216	n/a	0, 1, 2, 3, 4, 5, 6, 7, 8, 9,-1,-1, -1,-1,-1,-1,
1217	n/a	-1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1218	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1219	n/a	-1,10,11,12, 13,14,15,-1, -1,-1,-1,-1, -1,-1,-1,-1,
1220	n/a	-1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1
1221	n/a	};
1222	n/a
1223	n/a	#define hexval(c) table_hex[(unsigned int)(c)]
1224	n/a
1225	n/a	#define MAXLINESIZE 76
1226	n/a
1227	n/a
1228	n/a	/*[clinic input]
1229	n/a	binascii.a2b_qp
1230	n/a
1231	n/a	data: ascii_buffer
1232	n/a	header: int(c_default="0") = False
1233	n/a
1234	n/a	Decode a string of qp-encoded data.
1235	n/a	[clinic start generated code]*/
1236	n/a
1237	n/a	static PyObject *
1238	n/a	binascii_a2b_qp_impl(PyObject module, Py_buffer data, int header)
1239	n/a	/[clinic end generated code: output=e99f7846cfb9bc53 input=5187a0d3d8e54f3b]/
1240	n/a	{
1241	n/a	Py_ssize_t in, out;
1242	n/a	char ch;
1243	n/a	const unsigned char *ascii_data;
1244	n/a	unsigned char *odata;
1245	n/a	Py_ssize_t datalen = 0;
1246	n/a	PyObject *rv;
1247	n/a
1248	n/a	ascii_data = data->buf;
1249	n/a	datalen = data->len;
1250	n/a
1251	n/a	/* We allocate the output same size as input, this is overkill.
1252	n/a	* The previous implementation used calloc() so we'll zero out the
1253	n/a	* memory here too, since PyMem_Malloc() does not guarantee that.
1254	n/a	*/
1255	n/a	odata = (unsigned char *) PyMem_Malloc(datalen);
1256	n/a	if (odata == NULL) {
1257	n/a	PyErr_NoMemory();
1258	n/a	return NULL;
1259	n/a	}
1260	n/a	memset(odata, 0, datalen);
1261	n/a
1262	n/a	in = out = 0;
1263	n/a	while (in < datalen) {
1264	n/a	if (ascii_data[in] == '=') {
1265	n/a	in++;
1266	n/a	if (in >= datalen) break;
1267	n/a	/* Soft line breaks */
1268	n/a	if ((ascii_data[in] == '\n') \|\| (ascii_data[in] == '\r')) {
1269	n/a	if (ascii_data[in] != '\n') {
1270	n/a	while (in < datalen && ascii_data[in] != '\n') in++;
1271	n/a	}
1272	n/a	if (in < datalen) in++;
1273	n/a	}
1274	n/a	else if (ascii_data[in] == '=') {
1275	n/a	/* broken case from broken python qp */
1276	n/a	odata[out++] = '=';
1277	n/a	in++;
1278	n/a	}
1279	n/a	else if ((in + 1 < datalen) &&
1280	n/a	((ascii_data[in] >= 'A' && ascii_data[in] <= 'F') \|\|
1281	n/a	(ascii_data[in] >= 'a' && ascii_data[in] <= 'f') \|\|
1282	n/a	(ascii_data[in] >= '0' && ascii_data[in] <= '9')) &&
1283	n/a	((ascii_data[in+1] >= 'A' && ascii_data[in+1] <= 'F') \|\|
1284	n/a	(ascii_data[in+1] >= 'a' && ascii_data[in+1] <= 'f') \|\|
1285	n/a	(ascii_data[in+1] >= '0' && ascii_data[in+1] <= '9'))) {
1286	n/a	/* hexval */
1287	n/a	ch = hexval(ascii_data[in]) << 4;
1288	n/a	in++;
1289	n/a	ch \|= hexval(ascii_data[in]);
1290	n/a	in++;
1291	n/a	odata[out++] = ch;
1292	n/a	}
1293	n/a	else {
1294	n/a	odata[out++] = '=';
1295	n/a	}
1296	n/a	}
1297	n/a	else if (header && ascii_data[in] == '_') {
1298	n/a	odata[out++] = ' ';
1299	n/a	in++;
1300	n/a	}
1301	n/a	else {
1302	n/a	odata[out] = ascii_data[in];
1303	n/a	in++;
1304	n/a	out++;
1305	n/a	}
1306	n/a	}
1307	n/a	if ((rv = PyBytes_FromStringAndSize((char *)odata, out)) == NULL) {
1308	n/a	PyMem_Free(odata);
1309	n/a	return NULL;
1310	n/a	}
1311	n/a	PyMem_Free(odata);
1312	n/a	return rv;
1313	n/a	}
1314	n/a
1315	n/a	static int
1316	n/a	to_hex (unsigned char ch, unsigned char *s)
1317	n/a	{
1318	n/a	unsigned int uvalue = ch;
1319	n/a
1320	n/a	s[1] = "0123456789ABCDEF"[uvalue % 16];
1321	n/a	uvalue = (uvalue / 16);
1322	n/a	s[0] = "0123456789ABCDEF"[uvalue % 16];
1323	n/a	return 0;
1324	n/a	}
1325	n/a
1326	n/a	/* XXX: This is ridiculously complicated to be backward compatible
1327	n/a	* (mostly) with the quopri module. It doesn't re-create the quopri
1328	n/a	* module bug where text ending in CRLF has the CR encoded */
1329	n/a
1330	n/a	/*[clinic input]
1331	n/a	binascii.b2a_qp
1332	n/a
1333	n/a	data: Py_buffer
1334	n/a	quotetabs: int(c_default="0") = False
1335	n/a	istext: int(c_default="1") = True
1336	n/a	header: int(c_default="0") = False
1337	n/a
1338	n/a	Encode a string using quoted-printable encoding.
1339	n/a
1340	n/a	On encoding, when istext is set, newlines are not encoded, and white
1341	n/a	space at end of lines is. When istext is not set, \r and \n (CR/LF)
1342	n/a	are both encoded. When quotetabs is set, space and tabs are encoded.
1343	n/a	[clinic start generated code]*/
1344	n/a
1345	n/a	static PyObject *
1346	n/a	binascii_b2a_qp_impl(PyObject module, Py_buffer data, int quotetabs,
1347	n/a	int istext, int header)
1348	n/a	/[clinic end generated code: output=e9884472ebb1a94c input=7f2a9aaa008e92b2]/
1349	n/a	{
1350	n/a	Py_ssize_t in, out;
1351	n/a	const unsigned char *databuf;
1352	n/a	unsigned char *odata;
1353	n/a	Py_ssize_t datalen = 0, odatalen = 0;
1354	n/a	PyObject *rv;
1355	n/a	unsigned int linelen = 0;
1356	n/a	unsigned char ch;
1357	n/a	int crlf = 0;
1358	n/a	const unsigned char *p;
1359	n/a
1360	n/a	databuf = data->buf;
1361	n/a	datalen = data->len;
1362	n/a
1363	n/a	/* See if this string is using CRLF line ends */
1364	n/a	/* XXX: this function has the side effect of converting all of
1365	n/a	* the end of lines to be the same depending on this detection
1366	n/a	* here */
1367	n/a	p = (const unsigned char *) memchr(databuf, '\n', datalen);
1368	n/a	if ((p != NULL) && (p > databuf) && (*(p-1) == '\r'))
1369	n/a	crlf = 1;
1370	n/a
1371	n/a	/* First, scan to see how many characters need to be encoded */
1372	n/a	in = 0;
1373	n/a	while (in < datalen) {
1374	n/a	Py_ssize_t delta = 0;
1375	n/a	if ((databuf[in] > 126) \|\|
1376	n/a	(databuf[in] == '=') \|\|
1377	n/a	(header && databuf[in] == '_') \|\|
1378	n/a	((databuf[in] == '.') && (linelen == 0) &&
1379	n/a	(in + 1 == datalen \|\| databuf[in+1] == '\n' \|\|
1380	n/a	databuf[in+1] == '\r' \|\| databuf[in+1] == 0)) \|\|
1381	n/a	(!istext && ((databuf[in] == '\r') \|\| (databuf[in] == '\n'))) \|\|
1382	n/a	((databuf[in] == '\t' \|\| databuf[in] == ' ') && (in + 1 == datalen)) \|\|
1383	n/a	((databuf[in] < 33) &&
1384	n/a	(databuf[in] != '\r') && (databuf[in] != '\n') &&
1385	n/a	(quotetabs \|\| ((databuf[in] != '\t') && (databuf[in] != ' ')))))
1386	n/a	{
1387	n/a	if ((linelen + 3) >= MAXLINESIZE) {
1388	n/a	linelen = 0;
1389	n/a	if (crlf)
1390	n/a	delta += 3;
1391	n/a	else
1392	n/a	delta += 2;
1393	n/a	}
1394	n/a	linelen += 3;
1395	n/a	delta += 3;
1396	n/a	in++;
1397	n/a	}
1398	n/a	else {
1399	n/a	if (istext &&
1400	n/a	((databuf[in] == '\n') \|\|
1401	n/a	((in+1 < datalen) && (databuf[in] == '\r') &&
1402	n/a	(databuf[in+1] == '\n'))))
1403	n/a	{
1404	n/a	linelen = 0;
1405	n/a	/* Protect against whitespace on end of line */
1406	n/a	if (in && ((databuf[in-1] == ' ') \|\| (databuf[in-1] == '\t')))
1407	n/a	delta += 2;
1408	n/a	if (crlf)
1409	n/a	delta += 2;
1410	n/a	else
1411	n/a	delta += 1;
1412	n/a	if (databuf[in] == '\r')
1413	n/a	in += 2;
1414	n/a	else
1415	n/a	in++;
1416	n/a	}
1417	n/a	else {
1418	n/a	if ((in + 1 != datalen) &&
1419	n/a	(databuf[in+1] != '\n') &&
1420	n/a	(linelen + 1) >= MAXLINESIZE) {
1421	n/a	linelen = 0;
1422	n/a	if (crlf)
1423	n/a	delta += 3;
1424	n/a	else
1425	n/a	delta += 2;
1426	n/a	}
1427	n/a	linelen++;
1428	n/a	delta++;
1429	n/a	in++;
1430	n/a	}
1431	n/a	}
1432	n/a	if (PY_SSIZE_T_MAX - delta < odatalen) {
1433	n/a	PyErr_NoMemory();
1434	n/a	return NULL;
1435	n/a	}
1436	n/a	odatalen += delta;
1437	n/a	}
1438	n/a
1439	n/a	/* We allocate the output same size as input, this is overkill.
1440	n/a	* The previous implementation used calloc() so we'll zero out the
1441	n/a	* memory here too, since PyMem_Malloc() does not guarantee that.
1442	n/a	*/
1443	n/a	odata = (unsigned char *) PyMem_Malloc(odatalen);
1444	n/a	if (odata == NULL) {
1445	n/a	PyErr_NoMemory();
1446	n/a	return NULL;
1447	n/a	}
1448	n/a	memset(odata, 0, odatalen);
1449	n/a
1450	n/a	in = out = linelen = 0;
1451	n/a	while (in < datalen) {
1452	n/a	if ((databuf[in] > 126) \|\|
1453	n/a	(databuf[in] == '=') \|\|
1454	n/a	(header && databuf[in] == '_') \|\|
1455	n/a	((databuf[in] == '.') && (linelen == 0) &&
1456	n/a	(in + 1 == datalen \|\| databuf[in+1] == '\n' \|\|
1457	n/a	databuf[in+1] == '\r' \|\| databuf[in+1] == 0)) \|\|
1458	n/a	(!istext && ((databuf[in] == '\r') \|\| (databuf[in] == '\n'))) \|\|
1459	n/a	((databuf[in] == '\t' \|\| databuf[in] == ' ') && (in + 1 == datalen)) \|\|
1460	n/a	((databuf[in] < 33) &&
1461	n/a	(databuf[in] != '\r') && (databuf[in] != '\n') &&
1462	n/a	(quotetabs \|\| ((databuf[in] != '\t') && (databuf[in] != ' ')))))
1463	n/a	{
1464	n/a	if ((linelen + 3 )>= MAXLINESIZE) {
1465	n/a	odata[out++] = '=';
1466	n/a	if (crlf) odata[out++] = '\r';
1467	n/a	odata[out++] = '\n';
1468	n/a	linelen = 0;
1469	n/a	}
1470	n/a	odata[out++] = '=';
1471	n/a	to_hex(databuf[in], &odata[out]);
1472	n/a	out += 2;
1473	n/a	in++;
1474	n/a	linelen += 3;
1475	n/a	}
1476	n/a	else {
1477	n/a	if (istext &&
1478	n/a	((databuf[in] == '\n') \|\|
1479	n/a	((in+1 < datalen) && (databuf[in] == '\r') &&
1480	n/a	(databuf[in+1] == '\n'))))
1481	n/a	{
1482	n/a	linelen = 0;
1483	n/a	/* Protect against whitespace on end of line */
1484	n/a	if (out && ((odata[out-1] == ' ') \|\| (odata[out-1] == '\t'))) {
1485	n/a	ch = odata[out-1];
1486	n/a	odata[out-1] = '=';
1487	n/a	to_hex(ch, &odata[out]);
1488	n/a	out += 2;
1489	n/a	}
1490	n/a
1491	n/a	if (crlf) odata[out++] = '\r';
1492	n/a	odata[out++] = '\n';
1493	n/a	if (databuf[in] == '\r')
1494	n/a	in += 2;
1495	n/a	else
1496	n/a	in++;
1497	n/a	}
1498	n/a	else {
1499	n/a	if ((in + 1 != datalen) &&
1500	n/a	(databuf[in+1] != '\n') &&
1501	n/a	(linelen + 1) >= MAXLINESIZE) {
1502	n/a	odata[out++] = '=';
1503	n/a	if (crlf) odata[out++] = '\r';
1504	n/a	odata[out++] = '\n';
1505	n/a	linelen = 0;
1506	n/a	}
1507	n/a	linelen++;
1508	n/a	if (header && databuf[in] == ' ') {
1509	n/a	odata[out++] = '_';
1510	n/a	in++;
1511	n/a	}
1512	n/a	else {
1513	n/a	odata[out++] = databuf[in++];
1514	n/a	}
1515	n/a	}
1516	n/a	}
1517	n/a	}
1518	n/a	if ((rv = PyBytes_FromStringAndSize((char *)odata, out)) == NULL) {
1519	n/a	PyMem_Free(odata);
1520	n/a	return NULL;
1521	n/a	}
1522	n/a	PyMem_Free(odata);
1523	n/a	return rv;
1524	n/a	}
1525	n/a
1526	n/a	/* List of functions defined in the module */
1527	n/a
1528	n/a	static struct PyMethodDef binascii_module_methods[] = {
1529	n/a	BINASCII_A2B_UU_METHODDEF
1530	n/a	BINASCII_B2A_UU_METHODDEF
1531	n/a	BINASCII_A2B_BASE64_METHODDEF
1532	n/a	BINASCII_B2A_BASE64_METHODDEF
1533	n/a	BINASCII_A2B_HQX_METHODDEF
1534	n/a	BINASCII_B2A_HQX_METHODDEF
1535	n/a	BINASCII_A2B_HEX_METHODDEF
1536	n/a	BINASCII_B2A_HEX_METHODDEF
1537	n/a	BINASCII_HEXLIFY_METHODDEF
1538	n/a	BINASCII_UNHEXLIFY_METHODDEF
1539	n/a	BINASCII_RLECODE_HQX_METHODDEF
1540	n/a	BINASCII_RLEDECODE_HQX_METHODDEF
1541	n/a	BINASCII_CRC_HQX_METHODDEF
1542	n/a	BINASCII_CRC32_METHODDEF
1543	n/a	BINASCII_A2B_QP_METHODDEF
1544	n/a	BINASCII_B2A_QP_METHODDEF
1545	n/a	{NULL, NULL} /* sentinel */
1546	n/a	};
1547	n/a
1548	n/a
1549	n/a	/* Initialization function for the module (must be called PyInit_binascii) */
1550	n/a	PyDoc_STRVAR(doc_binascii, "Conversion between binary data and ASCII");
1551	n/a
1552	n/a
1553	n/a	static struct PyModuleDef binasciimodule = {
1554	n/a	PyModuleDef_HEAD_INIT,
1555	n/a	"binascii",
1556	n/a	doc_binascii,
1557	n/a	-1,
1558	n/a	binascii_module_methods,
1559	n/a	NULL,
1560	n/a	NULL,
1561	n/a	NULL,
1562	n/a	NULL
1563	n/a	};
1564	n/a
1565	n/a	PyMODINIT_FUNC
1566	n/a	PyInit_binascii(void)
1567	n/a	{
1568	n/a	PyObject m, d;
1569	n/a
1570	n/a	/* Create the module and add the functions */
1571	n/a	m = PyModule_Create(&binasciimodule);
1572	n/a	if (m == NULL)
1573	n/a	return NULL;
1574	n/a
1575	n/a	d = PyModule_GetDict(m);
1576	n/a
1577	n/a	Error = PyErr_NewException("binascii.Error", PyExc_ValueError, NULL);
1578	n/a	PyDict_SetItemString(d, "Error", Error);
1579	n/a	Incomplete = PyErr_NewException("binascii.Incomplete", NULL, NULL);
1580	n/a	PyDict_SetItemString(d, "Incomplete", Incomplete);
1581	n/a	if (PyErr_Occurred()) {
1582	n/a	Py_DECREF(m);
1583	n/a	m = NULL;
1584	n/a	}
1585	n/a	return m;
1586	n/a	}