Squashed 'third_party/allwpilib_2019/' content from commit bd05dfa1c

Change-Id: I2b1c2250cdb9b055133780c33593292098c375b7
git-subtree-dir: third_party/allwpilib_2019
git-subtree-split: bd05dfa1c7cca74c4fac451e7b9d6a37e7b53447
diff --git a/wpiutil/src/main/native/cpp/sha1.cpp b/wpiutil/src/main/native/cpp/sha1.cpp
new file mode 100644
index 0000000..e1346f4
--- /dev/null
+++ b/wpiutil/src/main/native/cpp/sha1.cpp
@@ -0,0 +1,316 @@
+/*
+    sha1.cpp - source code of
+
+    ============
+    SHA-1 in C++
+    ============
+
+    100% Public Domain.
+
+    Original C Code
+        -- Steve Reid <steve@edmweb.com>
+    Small changes to fit into bglibs
+        -- Bruce Guenter <bruce@untroubled.org>
+    Translation to simpler C++ Code
+        -- Volker Grabsch <vog@notjusthosting.com>
+    Safety fixes
+        -- Eugene Hopkinson <slowriot at voxelstorm dot com>
+*/
+
+#include "wpi/sha1.h"
+
+#include "wpi/SmallVector.h"
+#include "wpi/StringExtras.h"
+#include "wpi/raw_istream.h"
+#include "wpi/raw_ostream.h"
+
+using namespace wpi;
+
+static const size_t BLOCK_INTS =
+    16; /* number of 32bit integers per SHA1 block */
+static const size_t BLOCK_BYTES = BLOCK_INTS * 4;
+
+static void reset(uint32_t digest[], size_t& buf_size, uint64_t& transforms) {
+  /* SHA1 initialization constants */
+  digest[0] = 0x67452301;
+  digest[1] = 0xefcdab89;
+  digest[2] = 0x98badcfe;
+  digest[3] = 0x10325476;
+  digest[4] = 0xc3d2e1f0;
+
+  /* Reset counters */
+  buf_size = 0;
+  transforms = 0;
+}
+
+static uint32_t rol(const uint32_t value, const size_t bits) {
+  return (value << bits) | (value >> (32 - bits));
+}
+
+static uint32_t blk(const uint32_t block[BLOCK_INTS], const size_t i) {
+  return rol(block[(i + 13) & 15] ^ block[(i + 8) & 15] ^ block[(i + 2) & 15] ^
+                 block[i],
+             1);
+}
+
+/*
+ * (R0+R1), R2, R3, R4 are the different operations used in SHA1
+ */
+
+static void R0(const uint32_t block[BLOCK_INTS], const uint32_t v, uint32_t& w,
+               const uint32_t x, const uint32_t y, uint32_t& z,
+               const size_t i) {
+  z += ((w & (x ^ y)) ^ y) + block[i] + 0x5a827999 + rol(v, 5);
+  w = rol(w, 30);
+}
+
+static void R1(uint32_t block[BLOCK_INTS], const uint32_t v, uint32_t& w,
+               const uint32_t x, const uint32_t y, uint32_t& z,
+               const size_t i) {
+  block[i] = blk(block, i);
+  z += ((w & (x ^ y)) ^ y) + block[i] + 0x5a827999 + rol(v, 5);
+  w = rol(w, 30);
+}
+
+static void R2(uint32_t block[BLOCK_INTS], const uint32_t v, uint32_t& w,
+               const uint32_t x, const uint32_t y, uint32_t& z,
+               const size_t i) {
+  block[i] = blk(block, i);
+  z += (w ^ x ^ y) + block[i] + 0x6ed9eba1 + rol(v, 5);
+  w = rol(w, 30);
+}
+
+static void R3(uint32_t block[BLOCK_INTS], const uint32_t v, uint32_t& w,
+               const uint32_t x, const uint32_t y, uint32_t& z,
+               const size_t i) {
+  block[i] = blk(block, i);
+  z += (((w | x) & y) | (w & x)) + block[i] + 0x8f1bbcdc + rol(v, 5);
+  w = rol(w, 30);
+}
+
+static void R4(uint32_t block[BLOCK_INTS], const uint32_t v, uint32_t& w,
+               const uint32_t x, const uint32_t y, uint32_t& z,
+               const size_t i) {
+  block[i] = blk(block, i);
+  z += (w ^ x ^ y) + block[i] + 0xca62c1d6 + rol(v, 5);
+  w = rol(w, 30);
+}
+
+/*
+ * Hash a single 512-bit block. This is the core of the algorithm.
+ */
+
+static void do_transform(uint32_t digest[], uint32_t block[BLOCK_INTS],
+                         uint64_t& transforms) {
+  /* Copy digest[] to working vars */
+  uint32_t a = digest[0];
+  uint32_t b = digest[1];
+  uint32_t c = digest[2];
+  uint32_t d = digest[3];
+  uint32_t e = digest[4];
+
+  /* 4 rounds of 20 operations each. Loop unrolled. */
+  R0(block, a, b, c, d, e, 0);
+  R0(block, e, a, b, c, d, 1);
+  R0(block, d, e, a, b, c, 2);
+  R0(block, c, d, e, a, b, 3);
+  R0(block, b, c, d, e, a, 4);
+  R0(block, a, b, c, d, e, 5);
+  R0(block, e, a, b, c, d, 6);
+  R0(block, d, e, a, b, c, 7);
+  R0(block, c, d, e, a, b, 8);
+  R0(block, b, c, d, e, a, 9);
+  R0(block, a, b, c, d, e, 10);
+  R0(block, e, a, b, c, d, 11);
+  R0(block, d, e, a, b, c, 12);
+  R0(block, c, d, e, a, b, 13);
+  R0(block, b, c, d, e, a, 14);
+  R0(block, a, b, c, d, e, 15);
+  R1(block, e, a, b, c, d, 0);
+  R1(block, d, e, a, b, c, 1);
+  R1(block, c, d, e, a, b, 2);
+  R1(block, b, c, d, e, a, 3);
+  R2(block, a, b, c, d, e, 4);
+  R2(block, e, a, b, c, d, 5);
+  R2(block, d, e, a, b, c, 6);
+  R2(block, c, d, e, a, b, 7);
+  R2(block, b, c, d, e, a, 8);
+  R2(block, a, b, c, d, e, 9);
+  R2(block, e, a, b, c, d, 10);
+  R2(block, d, e, a, b, c, 11);
+  R2(block, c, d, e, a, b, 12);
+  R2(block, b, c, d, e, a, 13);
+  R2(block, a, b, c, d, e, 14);
+  R2(block, e, a, b, c, d, 15);
+  R2(block, d, e, a, b, c, 0);
+  R2(block, c, d, e, a, b, 1);
+  R2(block, b, c, d, e, a, 2);
+  R2(block, a, b, c, d, e, 3);
+  R2(block, e, a, b, c, d, 4);
+  R2(block, d, e, a, b, c, 5);
+  R2(block, c, d, e, a, b, 6);
+  R2(block, b, c, d, e, a, 7);
+  R3(block, a, b, c, d, e, 8);
+  R3(block, e, a, b, c, d, 9);
+  R3(block, d, e, a, b, c, 10);
+  R3(block, c, d, e, a, b, 11);
+  R3(block, b, c, d, e, a, 12);
+  R3(block, a, b, c, d, e, 13);
+  R3(block, e, a, b, c, d, 14);
+  R3(block, d, e, a, b, c, 15);
+  R3(block, c, d, e, a, b, 0);
+  R3(block, b, c, d, e, a, 1);
+  R3(block, a, b, c, d, e, 2);
+  R3(block, e, a, b, c, d, 3);
+  R3(block, d, e, a, b, c, 4);
+  R3(block, c, d, e, a, b, 5);
+  R3(block, b, c, d, e, a, 6);
+  R3(block, a, b, c, d, e, 7);
+  R3(block, e, a, b, c, d, 8);
+  R3(block, d, e, a, b, c, 9);
+  R3(block, c, d, e, a, b, 10);
+  R3(block, b, c, d, e, a, 11);
+  R4(block, a, b, c, d, e, 12);
+  R4(block, e, a, b, c, d, 13);
+  R4(block, d, e, a, b, c, 14);
+  R4(block, c, d, e, a, b, 15);
+  R4(block, b, c, d, e, a, 0);
+  R4(block, a, b, c, d, e, 1);
+  R4(block, e, a, b, c, d, 2);
+  R4(block, d, e, a, b, c, 3);
+  R4(block, c, d, e, a, b, 4);
+  R4(block, b, c, d, e, a, 5);
+  R4(block, a, b, c, d, e, 6);
+  R4(block, e, a, b, c, d, 7);
+  R4(block, d, e, a, b, c, 8);
+  R4(block, c, d, e, a, b, 9);
+  R4(block, b, c, d, e, a, 10);
+  R4(block, a, b, c, d, e, 11);
+  R4(block, e, a, b, c, d, 12);
+  R4(block, d, e, a, b, c, 13);
+  R4(block, c, d, e, a, b, 14);
+  R4(block, b, c, d, e, a, 15);
+
+  /* Add the working vars back into digest[] */
+  digest[0] += a;
+  digest[1] += b;
+  digest[2] += c;
+  digest[3] += d;
+  digest[4] += e;
+
+  /* Count the number of transformations */
+  transforms++;
+}
+
+static void buffer_to_block(const unsigned char* buffer,
+                            uint32_t block[BLOCK_INTS]) {
+  /* Convert the std::string (byte buffer) to a uint32_t array (MSB) */
+  for (size_t i = 0; i < BLOCK_INTS; i++) {
+    block[i] = (buffer[4 * i + 3] & 0xff) | (buffer[4 * i + 2] & 0xff) << 8 |
+               (buffer[4 * i + 1] & 0xff) << 16 |
+               (buffer[4 * i + 0] & 0xff) << 24;
+  }
+}
+
+SHA1::SHA1() { reset(digest, buf_size, transforms); }
+
+void SHA1::Update(StringRef s) {
+  raw_mem_istream is(makeArrayRef(s.data(), s.size()));
+  Update(is);
+}
+
+void SHA1::Update(raw_istream& is) {
+  while (true) {
+    buf_size += is.readsome(&buffer[buf_size], BLOCK_BYTES - buf_size);
+    if (buf_size != BLOCK_BYTES) {
+      return;
+    }
+    uint32_t block[BLOCK_INTS];
+    buffer_to_block(buffer, block);
+    do_transform(digest, block, transforms);
+    buf_size = 0;
+  }
+}
+
+/*
+ * Add padding and return the message digest.
+ */
+
+static void finalize(uint32_t digest[], unsigned char* buffer, size_t& buf_size,
+                     uint64_t& transforms, raw_ostream& os, bool hex) {
+  /* Total number of hashed bits */
+  uint64_t total_bits = (transforms * BLOCK_BYTES + buf_size) * 8;
+
+  /* Padding */
+  buffer[buf_size++] = 0x80;
+  for (size_t i = buf_size; i < BLOCK_BYTES; ++i) {
+    buffer[i] = 0x00;
+  }
+
+  uint32_t block[BLOCK_INTS];
+  buffer_to_block(buffer, block);
+
+  if (buf_size > BLOCK_BYTES - 8) {
+    do_transform(digest, block, transforms);
+    for (size_t i = 0; i < BLOCK_INTS - 2; i++) {
+      block[i] = 0;
+    }
+  }
+
+  /* Append total_bits, split this uint64_t into two uint32_t */
+  block[BLOCK_INTS - 1] = total_bits;
+  block[BLOCK_INTS - 2] = (total_bits >> 32);
+  do_transform(digest, block, transforms);
+
+  /* Hex string */
+  static const char* const LUT = "0123456789abcdef";
+  for (size_t i = 0; i < 5; i++) {
+    uint32_t v = digest[i];
+    if (hex) {
+      os << LUT[(v >> 28) & 0xf] << LUT[(v >> 24) & 0xf] << LUT[(v >> 20) & 0xf]
+         << LUT[(v >> 16) & 0xf] << LUT[(v >> 12) & 0xf] << LUT[(v >> 8) & 0xf]
+         << LUT[(v >> 4) & 0xf] << LUT[(v >> 0) & 0xf];
+    } else {
+      os.write(static_cast<unsigned char>((v >> 24) & 0xff));
+      os.write(static_cast<unsigned char>((v >> 16) & 0xff));
+      os.write(static_cast<unsigned char>((v >> 8) & 0xff));
+      os.write(static_cast<unsigned char>((v >> 0) & 0xff));
+    }
+  }
+
+  /* Reset for next run */
+  reset(digest, buf_size, transforms);
+}
+
+std::string SHA1::Final() {
+  std::string out;
+  raw_string_ostream os(out);
+
+  finalize(digest, buffer, buf_size, transforms, os, true);
+
+  return os.str();
+}
+
+StringRef SHA1::Final(SmallVectorImpl<char>& buf) {
+  raw_svector_ostream os(buf);
+
+  finalize(digest, buffer, buf_size, transforms, os, true);
+
+  return os.str();
+}
+
+StringRef SHA1::RawFinal(SmallVectorImpl<char>& buf) {
+  raw_svector_ostream os(buf);
+
+  finalize(digest, buffer, buf_size, transforms, os, false);
+
+  return os.str();
+}
+
+std::string SHA1::FromFile(StringRef filename) {
+  std::error_code ec;
+  raw_fd_istream stream(filename, ec);
+  SHA1 checksum;
+  checksum.Update(stream);
+  return checksum.Final();
+}