Botan: src/math/bigint/big_io.cpp Source File

Botan 1.10.16

big_io.cpp
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1 /*
2 * BigInt Input/Output
3 * (C) 1999-2007 Jack Lloyd
4 *
5 * Distributed under the terms of the Botan license
6 */
7
8 #include <botan/bigint.h>
9 #include <iostream>
10
11 namespace Botan {
12
13 /*
14 * Write the BigInt into a stream
15 */
16 std::ostream& operator<<(std::ostream& stream, const BigInt& n)
17 {
18 BigInt::Base base = BigInt::Decimal;
19 if(stream.flags() & std::ios::hex)
20 base = BigInt::Hexadecimal;
21 else if(stream.flags() & std::ios::oct)
22 base = BigInt::Octal;
23
24 if(n == 0)
25 stream.write("0", 1);
26 else
27 {
28 if(n < 0)
29 stream.write("-", 1);
30 SecureVector<byte> buffer = BigInt::encode(n, base);
31 size_t skip = 0;
32 while(buffer[skip] == '0' && skip < buffer.size())
33 ++skip;
34 stream.write(reinterpret_cast<const char*>(&buffer[0]) + skip,
35 buffer.size() - skip);
36 }
37 if(!stream.good())
38 throw Stream_IO_Error("BigInt output operator has failed");
39 return stream;
40 }
41
42 /*
43 * Read the BigInt from a stream
44 */
45 std::istream& operator>>(std::istream& stream, BigInt& n)
46 {
47 std::string str;
48 std::getline(stream, str);
49 if(stream.bad() || (stream.fail() && !stream.eof()))
50 throw Stream_IO_Error("BigInt input operator has failed");
51 n = BigInt(str);
52 return stream;
53 }
54
55 }
Botan::Stream_IO_Error
Definition: exceptn.h:165
Botan::BigInt::Hexadecimal
Definition: bigint.h:28
Botan::BigInt
Definition: bigint.h:22
Botan::BigInt::Decimal
Definition: bigint.h:28
Botan::BigInt::encode
static SecureVector< byte > encode(const BigInt &n, Base base=Binary)
Definition: big_code.cpp:64
Botan::operator>>
int operator>>(int fd, Pipe &pipe)
Definition: fd_unix.cpp:39
Botan::operator<<
int operator<<(int fd, Pipe &pipe)
Definition: fd_unix.cpp:17
Botan::BigInt::Octal
Definition: bigint.h:28
Botan
Definition: algo_base.h:14
Botan::BigInt::Base
Base
Definition: bigint.h:28
Botan::MemoryRegion::size
size_t size() const
Definition: secmem.h:29
Botan::SecureVector< byte >