text: /* SHA1 module */
  
  /* This module provides an interface to the SHA1 algorithm */
  
  /* See below for information about the original code this module was
     based upon. Additional work performed by:
  
     Andrew Kuchling (amk@amk.ca)
     Greg Stein (gstein@lyra.org)
     Trevor Perrin (trevp@trevp.net)
  
     Copyright (C) 2005-2007   Gregory P. Smith (greg@krypto.org)
     Licensed to PSF under a Contributor Agreement.
  
  */
  
  /* SHA1 objects */
  
  #include "Python.h"
  #include "hashlib.h"
  
  /*[clinic input]
  module _sha1
  class SHA1Type "SHA1object *" "&PyType_Type"
  [clinic start generated code]*/
  /*[clinic end generated code: output=da39a3ee5e6b4b0d input=3dc9a20d1becb759]*/
  
  /* Some useful types */
  
  #if SIZEOF_INT == 4
  typedef unsigned int SHA1_INT32;        /* 32-bit integer */
  typedef PY_LONG_LONG SHA1_INT64;        /* 64-bit integer */
  #else
  /* not defined. compilation will die. */
  #endif
  
  /* The SHA1 block size and message digest sizes, in bytes */
  
  #define SHA1_BLOCKSIZE    64
  #define SHA1_DIGESTSIZE   20
  
  /* The structure for storing SHA1 info */
  
  struct sha1_state {
      SHA1_INT64 length;
      SHA1_INT32 state[5], curlen;
      unsigned char buf[SHA1_BLOCKSIZE];
  };
  
  typedef struct {
      PyObject_HEAD
  
      struct sha1_state hash_state;
  } SHA1object;
  
  #include "clinic/sha1module.c.h"
  
  /* ------------------------------------------------------------------------
   *
   * This code for the SHA1 algorithm was noted as public domain. The
   * original headers are pasted below.
   *
   * Several changes have been made to make it more compatible with the
   * Python environment and desired interface.
   *
   */
  
  /* LibTomCrypt, modular cryptographic library -- Tom St Denis
   *
   * LibTomCrypt is a library that provides various cryptographic
   * algorithms in a highly modular and flexible manner.
   *
   * The library is free for all purposes without any express
   * guarantee it works.
   *
   * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
   */
  
  /* rotate the hard way (platform optimizations could be done) */
  #define ROL(x, y) ( (((unsigned long)(x)<<(unsigned long)((y)&31)) | (((unsigned long)(x)&0xFFFFFFFFUL)>>(unsigned long)(32-((y)&31)))) & 0xFFFFFFFFUL)
  #define ROLc(x, y) ( (((unsigned long)(x)<<(unsigned long)((y)&31)) | (((unsigned long)(x)&0xFFFFFFFFUL)>>(unsigned long)(32-((y)&31)))) & 0xFFFFFFFFUL)
  
  /* Endian Neutral macros that work on all platforms */
  
  #define STORE32H(x, y)                                                                     \
       { (y)[0] = (unsigned char)(((x)>>24)&255); (y)[1] = (unsigned char)(((x)>>16)&255);   \
         (y)[2] = (unsigned char)(((x)>>8)&255); (y)[3] = (unsigned char)((x)&255); }
  
  #define LOAD32H(x, y)                            \
       { x = ((unsigned long)((y)[0] & 255)<<24) | \
             ((unsigned long)((y)[1] & 255)<<16) | \
             ((unsigned long)((y)[2] & 255)<<8)  | \
             ((unsigned long)((y)[3] & 255)); }
  
  #define STORE64H(x, y)                                                                     \
     { (y)[0] = (unsigned char)(((x)>>56)&255); (y)[1] = (unsigned char)(((x)>>48)&255);     \
       (y)[2] = (unsigned char)(((x)>>40)&255); (y)[3] = (unsigned char)(((x)>>32)&255);     \
       (y)[4] = (unsigned char)(((x)>>24)&255); (y)[5] = (unsigned char)(((x)>>16)&255);     \
       (y)[6] = (unsigned char)(((x)>>8)&255); (y)[7] = (unsigned char)((x)&255); }
  
  
  /* SHA1 macros */
  
  #define F0(x,y,z)  (z ^ (x & (y ^ z)))
  #define F1(x,y,z)  (x ^ y ^ z)
  #define F2(x,y,z)  ((x & y) | (z & (x | y)))
  #define F3(x,y,z)  (x ^ y ^ z)
  
  static void sha1_compress(struct sha1_state *sha1, unsigned char *buf)
  {
      SHA1_INT32 a,b,c,d,e,W[80],i;
  
      /* copy the state into 512-bits into W[0..15] */
      for (i = 0; i < 16; i++) {
          LOAD32H(W[i], buf + (4*i));
      }
  
      /* copy state */
      a = sha1->state[0];
      b = sha1->state[1];
      c = sha1->state[2];
      d = sha1->state[3];
      e = sha1->state[4];
  
      /* expand it */
      for (i = 16; i < 80; i++) {
          W[i] = ROL(W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16], 1);
      }
  
      /* compress */
      /* round one */
      #define FF_0(a,b,c,d,e,i) e = (ROLc(a, 5) + F0(b,c,d) + e + W[i] + 0x5a827999UL); b = ROLc(b, 30);
      #define FF_1(a,b,c,d,e,i) e = (ROLc(a, 5) + F1(b,c,d) + e + W[i] + 0x6ed9eba1UL); b = ROLc(b, 30);
      #define FF_2(a,b,c,d,e,i) e = (ROLc(a, 5) + F2(b,c,d) + e + W[i] + 0x8f1bbcdcUL); b = ROLc(b, 30);
      #define FF_3(a,b,c,d,e,i) e = (ROLc(a, 5) + F3(b,c,d) + e + W[i] + 0xca62c1d6UL); b = ROLc(b, 30);
  
      for (i = 0; i < 20; ) {
         FF_0(a,b,c,d,e,i++);
         FF_0(e,a,b,c,d,i++);
         FF_0(d,e,a,b,c,i++);
         FF_0(c,d,e,a,b,i++);
         FF_0(b,c,d,e,a,i++);
      }
  
      /* round two */
      for (; i < 40; )  {
         FF_1(a,b,c,d,e,i++);
         FF_1(e,a,b,c,d,i++);
         FF_1(d,e,a,b,c,i++);
         FF_1(c,d,e,a,b,i++);
         FF_1(b,c,d,e,a,i++);
      }
  
      /* round three */
      for (; i < 60; )  {
         FF_2(a,b,c,d,e,i++);
         FF_2(e,a,b,c,d,i++);
         FF_2(d,e,a,b,c,i++);
         FF_2(c,d,e,a,b,i++);
         FF_2(b,c,d,e,a,i++);
      }
  
      /* round four */
      for (; i < 80; )  {
         FF_3(a,b,c,d,e,i++);
         FF_3(e,a,b,c,d,i++);
         FF_3(d,e,a,b,c,i++);
         FF_3(c,d,e,a,b,i++);
         FF_3(b,c,d,e,a,i++);
      }
  
      #undef FF_0
      #undef FF_1
      #undef FF_2
      #undef FF_3
  
      /* store */
      sha1->state[0] = sha1->state[0] + a;
      sha1->state[1] = sha1->state[1] + b;
      sha1->state[2] = sha1->state[2] + c;
      sha1->state[3] = sha1->state[3] + d;
      sha1->state[4] = sha1->state[4] + e;
  }
  
  /**
     Initialize the hash state
     @param sha1   The hash state you wish to initialize
  */
  static void
  sha1_init(struct sha1_state *sha1)
  {
     assert(sha1 != NULL);
     sha1->state[0] = 0x67452301UL;
     sha1->state[1] = 0xefcdab89UL;
     sha1->state[2] = 0x98badcfeUL;
     sha1->state[3] = 0x10325476UL;
     sha1->state[4] = 0xc3d2e1f0UL;
     sha1->curlen = 0;
     sha1->length = 0;
  }
  
  /**
     Process a block of memory though the hash
     @param sha1   The hash state
     @param in     The data to hash
     @param inlen  The length of the data (octets)
  */
  static void
  sha1_process(struct sha1_state *sha1,
                    const unsigned char *in, Py_ssize_t inlen)
  {
      Py_ssize_t n;
  
      assert(sha1 != NULL);
      assert(in != NULL);
      assert(sha1->curlen <= sizeof(sha1->buf));
  
      while (inlen > 0) {
          if (sha1->curlen == 0 && inlen >= SHA1_BLOCKSIZE) {
             sha1_compress(sha1, (unsigned char *)in);
             sha1->length   += SHA1_BLOCKSIZE * 8;
             in             += SHA1_BLOCKSIZE;
             inlen          -= SHA1_BLOCKSIZE;
          } else {
             n = Py_MIN(inlen, (Py_ssize_t)(SHA1_BLOCKSIZE - sha1->curlen));
             memcpy(sha1->buf + sha1->curlen, in, (size_t)n);
             sha1->curlen   += (SHA1_INT32)n;
             in             += n;
             inlen          -= n;
             if (sha1->curlen == SHA1_BLOCKSIZE) {
                sha1_compress(sha1, sha1->buf);
                sha1->length += 8*SHA1_BLOCKSIZE;
                sha1->curlen = 0;
             }
         }
      }
  }
  
  /**
     Terminate the hash to get the digest
     @param sha1  The hash state
     @param out [out] The destination of the hash (20 bytes)
  */
  static void
  sha1_done(struct sha1_state *sha1, unsigned char *out)
  {
      int i;
  
      assert(sha1 != NULL);
      assert(out != NULL);
      assert(sha1->curlen < sizeof(sha1->buf));
  
      /* increase the length of the message */
      sha1->length += sha1->curlen * 8;
  
      /* append the '1' bit */
      sha1->buf[sha1->curlen++] = (unsigned char)0x80;
  
      /* if the length is currently above 56 bytes we append zeros
       * then compress.  Then we can fall back to padding zeros and length
       * encoding like normal.
       */
      if (sha1->curlen > 56) {
          while (sha1->curlen < 64) {
              sha1->buf[sha1->curlen++] = (unsigned char)0;
          }
          sha1_compress(sha1, sha1->buf);
          sha1->curlen = 0;
      }
  
      /* pad upto 56 bytes of zeroes */
      while (sha1->curlen < 56) {
          sha1->buf[sha1->curlen++] = (unsigned char)0;
      }
  
      /* store length */
      STORE64H(sha1->length, sha1->buf+56);
      sha1_compress(sha1, sha1->buf);
  
      /* copy output */
      for (i = 0; i < 5; i++) {
          STORE32H(sha1->state[i], out+(4*i));
      }
  }
  
  
  /* .Source: /cvs/libtom/libtomcrypt/src/hashes/sha1.c,v $ */
  /* .Revision: 1.10 $ */
  /* .Date: 2007/05/12 14:25:28 $ */
  
  /*
   * End of copied SHA1 code.
   *
   * ------------------------------------------------------------------------
   */
  
  static PyTypeObject SHA1type;
  
  
  static SHA1object *
  newSHA1object(void)
  {
      return (SHA1object *)PyObject_New(SHA1object, &SHA1type);
  }
  
  
  /* Internal methods for a hash object */
  
  static void
  SHA1_dealloc(PyObject *ptr)
  {
      PyObject_Del(ptr);
  }
  
  
  /* External methods for a hash object */
  
  /*[clinic input]
  SHA1Type.copy
  
  Return a copy of the hash object.
  [clinic start generated code]*/
  
  static PyObject *
  SHA1Type_copy_impl(SHA1object *self)
  /*[clinic end generated code: output=b4e001264620f02a input=b7eae10df6f89b36]*/
  {
      SHA1object *newobj;
  
      if ((newobj = newSHA1object()) == NULL)
          return NULL;
  
      newobj->hash_state = self->hash_state;
      return (PyObject *)newobj;
  }
  
  /*[clinic input]
  SHA1Type.digest
  
  Return the digest value as a string of binary data.
  [clinic start generated code]*/
  
  static PyObject *
  SHA1Type_digest_impl(SHA1object *self)
  /*[clinic end generated code: output=2f05302a7aa2b5cb input=205d47e1927fd009]*/
  {
      unsigned char digest[SHA1_DIGESTSIZE];
      struct sha1_state temp;
  
      temp = self->hash_state;
      sha1_done(&temp, digest);
      return PyBytes_FromStringAndSize((const char *)digest, SHA1_DIGESTSIZE);
  }
  
  /*[clinic input]
  SHA1Type.hexdigest
  
  Return the digest value as a string of hexadecimal digits.
  [clinic start generated code]*/
  
  static PyObject *
  SHA1Type_hexdigest_impl(SHA1object *self)
  /*[clinic end generated code: output=4161fd71e68c6659 input=97691055c0c74ab0]*/
  {
      unsigned char digest[SHA1_DIGESTSIZE];
      struct sha1_state temp;
      PyObject *retval;
      Py_UCS1 *hex_digest;
      int i, j;
  
      /* Get the raw (binary) digest value */
      temp = self->hash_state;
      sha1_done(&temp, digest);
  
      /* Create a new string */
      retval = PyUnicode_New(SHA1_DIGESTSIZE * 2, 127);
      if (!retval)
              return NULL;
      hex_digest = PyUnicode_1BYTE_DATA(retval);
  
      /* Make hex version of the digest */
      for(i=j=0; i<SHA1_DIGESTSIZE; i++) {
          unsigned char c;
          c = (digest[i] >> 4) & 0xf;
          hex_digest[j++] = Py_hexdigits[c];
          c = (digest[i] & 0xf);
          hex_digest[j++] = Py_hexdigits[c];
      }
  #ifdef Py_DEBUG
      assert(_PyUnicode_CheckConsistency(retval, 1));
  #endif
      return retval;
  }
  
  /*[clinic input]
  SHA1Type.update
  
      obj: object
      /
  
  Update this hash object's state with the provided string.
  [clinic start generated code]*/
  
  static PyObject *
  SHA1Type_update(SHA1object *self, PyObject *obj)
  /*[clinic end generated code: output=d9902f0e5015e9ae input=aad8e07812edbba3]*/
  {
      Py_buffer buf;
  
      GET_BUFFER_VIEW_OR_ERROUT(obj, &buf);
  
      sha1_process(&self->hash_state, buf.buf, buf.len);
  
      PyBuffer_Release(&buf);
      Py_INCREF(Py_None);
      return Py_None;
  }
  
  static PyMethodDef SHA1_methods[] = {
      SHA1TYPE_COPY_METHODDEF
      SHA1TYPE_DIGEST_METHODDEF
      SHA1TYPE_HEXDIGEST_METHODDEF
      SHA1TYPE_UPDATE_METHODDEF
      {NULL,        NULL}         /* sentinel */
  };
  
  static PyObject *
  SHA1_get_block_size(PyObject *self, void *closure)
  {
      return PyLong_FromLong(SHA1_BLOCKSIZE);
  }
  
  static PyObject *
  SHA1_get_name(PyObject *self, void *closure)
  {
      return PyUnicode_FromStringAndSize("sha1", 4);
  }
  
  static PyObject *
  sha1_get_digest_size(PyObject *self, void *closure)
  {
      return PyLong_FromLong(SHA1_DIGESTSIZE);
  }
  
  
  static PyGetSetDef SHA1_getseters[] = {
      {"block_size",
       (getter)SHA1_get_block_size, NULL,
       NULL,
       NULL},
      {"name",
       (getter)SHA1_get_name, NULL,
       NULL,
       NULL},
      {"digest_size",
       (getter)sha1_get_digest_size, NULL,
       NULL,
       NULL},
      {NULL}  /* Sentinel */
  };
  
  static PyTypeObject SHA1type = {
      PyVarObject_HEAD_INIT(NULL, 0)
      "_sha1.sha1",               /*tp_name*/
      sizeof(SHA1object), /*tp_size*/
      0,                  /*tp_itemsize*/
      /* methods */
      SHA1_dealloc,       /*tp_dealloc*/
      0,                  /*tp_print*/
      0,                  /*tp_getattr*/
      0,                  /*tp_setattr*/
      0,                  /*tp_reserved*/
      0,                  /*tp_repr*/
      0,                  /*tp_as_number*/
      0,                  /*tp_as_sequence*/
      0,                  /*tp_as_mapping*/
      0,                  /*tp_hash*/
      0,                  /*tp_call*/
      0,                  /*tp_str*/
      0,                  /*tp_getattro*/
      0,                  /*tp_setattro*/
      0,                  /*tp_as_buffer*/
      Py_TPFLAGS_DEFAULT, /*tp_flags*/
      0,                  /*tp_doc*/
      0,                  /*tp_traverse*/
      0,                  /*tp_clear*/
      0,                  /*tp_richcompare*/
      0,                  /*tp_weaklistoffset*/
      0,                  /*tp_iter*/
      0,                  /*tp_iternext*/
      SHA1_methods,       /* tp_methods */
      NULL,               /* tp_members */
      SHA1_getseters,      /* tp_getset */
  };
  
  
  /* The single module-level function: new() */
  
  /*[clinic input]
  _sha1.sha1
  
      string: object(c_default="NULL") = b''
  
  Return a new SHA1 hash object; optionally initialized with a string.
  [clinic start generated code]*/
  
  static PyObject *
  _sha1_sha1_impl(PyModuleDef *module, PyObject *string)
  /*[clinic end generated code: output=3e4e841386b9e8db input=27ea54281d995ec2]*/
  {
      SHA1object *new;
      Py_buffer buf;
  
      if (string)
          GET_BUFFER_VIEW_OR_ERROUT(string, &buf);
  
      if ((new = newSHA1object()) == NULL) {
          if (string)
              PyBuffer_Release(&buf);
          return NULL;
      }
  
      sha1_init(&new->hash_state);
  
      if (PyErr_Occurred()) {
          Py_DECREF(new);
          if (string)
              PyBuffer_Release(&buf);
          return NULL;
      }
      if (string) {
          sha1_process(&new->hash_state, buf.buf, buf.len);
          PyBuffer_Release(&buf);
      }
  
      return (PyObject *)new;
  }
  
  
  /* List of functions exported by this module */
  
  static struct PyMethodDef SHA1_functions[] = {
      _SHA1_SHA1_METHODDEF
      {NULL,      NULL}            /* Sentinel */
  };
  
  
  /* Initialize this module. */
  
  #define insint(n,v) { PyModule_AddIntConstant(m,n,v); }
  
  
  static struct PyModuleDef _sha1module = {
          PyModuleDef_HEAD_INIT,
          "_sha1",
          NULL,
          -1,
          SHA1_functions,
          NULL,
          NULL,
          NULL,
          NULL
  };
  
  PyMODINIT_FUNC
  PyInit__sha1(void)
  {
      PyObject *m;
  
      Py_TYPE(&SHA1type) = &PyType_Type;
      if (PyType_Ready(&SHA1type) < 0)
          return NULL;
  
      m = PyModule_Create(&_sha1module);
      if (m == NULL)
          return NULL;
  
      Py_INCREF((PyObject *)&SHA1type);
      PyModule_AddObject(m, "SHA1Type", (PyObject *)&SHA1type);
      return m;
  }
  