Arduino C/C++ 更改函数名称

Question

大家好，我是 C 世界的新手，所以这是我的问题。

我有以下 .h 和 .cpp 文件，如下所示：

.h:

#ifndef Sha256_h
#define Sha256_h
#include "sha256_config.h"

#if defined(SHA256_LINUX)
    class Sha256Class
#else
    class Sha256Class : public Print
#endif
{
  public:
    union _buffer {
        uint8_t b[BLOCK_LENGTH];
        uint32_t w[BLOCK_LENGTH/4];
    };

    union _state {
        uint8_t b[HASH_LENGTH];
        uint32_t w[HASH_LENGTH/4];
    };

    void init(void);
    void initHmac(const uint8_t* secret, int secretLength);
    uint8_t* result(void);
    uint8_t* resultHmac(void);

    #if  defined(SHA256_LINUX)
        virtual size_t write(uint8_t);
        size_t write_L(const char *str);
        size_t write_L(const uint8_t *buffer, size_t size);
        size_t print(const char* str);  
        double millis();
    #else
        virtual size_t write(uint8_t);
        using Print::write;
    #endif

  private:
    void pad();
    void addUncounted(uint8_t data);
    void hashBlock();
    uint32_t ror32(uint32_t number, uint8_t bits);
    _buffer buffer;
    uint8_t bufferOffset;
    _state state;
    uint32_t byteCount;
    uint8_t keyBuffer[BLOCK_LENGTH];
    uint8_t innerHash[HASH_LENGTH];

    #if defined(SHA256_LINUX)
        timeval tv;
    #endif
};

extern Sha256Class Sha256;
#endif

.cpp:

#include "sha256.h"

uint32_t sha256K[] PROGMEM = {
  0x428a2f98,0x71374491,0xb5c0fbcf,0xe9b5dba5,0x3956c25b,0x59f111f1,0x923f82a4,0xab1c5ed5,
  0xd807aa98,0x12835b01,0x243185be,0x550c7dc3,0x72be5d74,0x80deb1fe,0x9bdc06a7,0xc19bf174,
  0xe49b69c1,0xefbe4786,0x0fc19dc6,0x240ca1cc,0x2de92c6f,0x4a7484aa,0x5cb0a9dc,0x76f988da,
  0x983e5152,0xa831c66d,0xb00327c8,0xbf597fc7,0xc6e00bf3,0xd5a79147,0x06ca6351,0x14292967,
  0x27b70a85,0x2e1b2138,0x4d2c6dfc,0x53380d13,0x650a7354,0x766a0abb,0x81c2c92e,0x92722c85,
  0xa2bfe8a1,0xa81a664b,0xc24b8b70,0xc76c51a3,0xd192e819,0xd6990624,0xf40e3585,0x106aa070,
  0x19a4c116,0x1e376c08,0x2748774c,0x34b0bcb5,0x391c0cb3,0x4ed8aa4a,0x5b9cca4f,0x682e6ff3,
  0x748f82ee,0x78a5636f,0x84c87814,0x8cc70208,0x90befffa,0xa4506ceb,0xbef9a3f7,0xc67178f2
};

#define BUFFER_SIZE 64

uint8_t sha256InitState[] PROGMEM = {
  0x67,0xe6,0x09,0x6a,
  0x85,0xae,0x67,0xbb,
  0x72,0xf3,0x6e,0x3c,
  0x3a,0xf5,0x4f,0xa5,
  0x7f,0x52,0x0e,0x51,
  0x8c,0x68,0x05,0x9b,
  0xab,0xd9,0x83,0x1f,
  0x19,0xcd,0xe0,0x5b
};

void Sha256Class::init(void) {
  memcpy_P(state.b,sha256InitState,32);
  byteCount = 0;
  bufferOffset = 0;
}

uint32_t Sha256Class::ror32(uint32_t number, uint8_t bits) {
  return ((number << (32-bits)) | (number >> bits));
}

void Sha256Class::hashBlock() {
  uint8_t i;
  uint32_t a,b,c,d,e,f,g,h,t1,t2;

  a=state.w[0];
  b=state.w[1];
  c=state.w[2];
  d=state.w[3];
  e=state.w[4];
  f=state.w[5];
  g=state.w[6];
  h=state.w[7];

  for (i=0; i<64; i++) {
    if (i>=16) {
      t1 = buffer.w[i&15] + buffer.w[(i-7)&15];
      t2 = buffer.w[(i-2)&15];
      t1 += ror32(t2,17) ^ ror32(t2,19) ^ (t2>>10);
      t2 = buffer.w[(i-15)&15];
      t1 += ror32(t2,7) ^ ror32(t2,18) ^ (t2>>3);
      buffer.w[i&15] = t1;
    }

    t1 = h;
    t1 += ror32(e,6) ^ ror32(e,11) ^ ror32(e,25);
    t1 += g ^ (e & (g ^ f));
    t1 += pgm_read_dword(sha256K+i);
    t1 += buffer.w[i&15];
    t2 = ror32(a,2) ^ ror32(a,13) ^ ror32(a,22);
    t2 += ((b & c) | (a & (b | c)));
    h=g; g=f; f=e; e=d+t1; d=c; c=b; b=a; a=t1+t2;
  }

  state.w[0] += a;
  state.w[1] += b;
  state.w[2] += c;
  state.w[3] += d;
  state.w[4] += e;
  state.w[5] += f;
  state.w[6] += g;
  state.w[7] += h;
}

void Sha256Class::addUncounted(uint8_t data) {
  buffer.b[bufferOffset ^ 3] = data;
  bufferOffset++;

  if (bufferOffset == BUFFER_SIZE) {
    hashBlock();
    bufferOffset = 0;
  }
}

size_t Sha256Class::write(uint8_t data) {
  ++byteCount;
  addUncounted(data);

  return 1;
}

void Sha256Class::pad() {
  addUncounted(0x80);

  while (bufferOffset != 56) addUncounted(0x00);

  addUncounted(0);
  addUncounted(0);
  addUncounted(0);
  addUncounted(byteCount >> 29);
  addUncounted(byteCount >> 21);
  addUncounted(byteCount >> 13);
  addUncounted(byteCount >> 5);
  addUncounted(byteCount << 3);
}


uint8_t* Sha256Class::result(void) {
  pad();

  for (int i=0; i<8; i++) {
    uint32_t a,b;

    a=state.w[i];
    b=a<<24;
    b|=(a<<8) & 0x00ff0000;
    b|=(a>>8) & 0x0000ff00;
    b|=a>>24;
    state.w[i]=b;
  }

  return state.b;
}

#define HMAC_IPAD 0x36
#define HMAC_OPAD 0x5c

uint8_t keyBuffer[BLOCK_LENGTH];
uint8_t innerHash[HASH_LENGTH];

void Sha256Class::initHmac(const uint8_t* key, int keyLength) {
  uint8_t i;

  memset(keyBuffer,0,BLOCK_LENGTH);

  if (keyLength > BLOCK_LENGTH) {
    init();
    for (;keyLength--;) write(*key++);

    memcpy(keyBuffer,result(),HASH_LENGTH);
  } else {
    memcpy(keyBuffer,key,keyLength);
  }

  init();

  for (i=0; i<BLOCK_LENGTH; i++) {
    write(keyBuffer[i] ^ HMAC_IPAD);
  }
}

uint8_t* Sha256Class::resultHmac(void) {
  uint8_t i;

  memcpy(innerHash,result(),HASH_LENGTH);
  init();

  for (i=0; i<BLOCK_LENGTH; i++) write(keyBuffer[i] ^ HMAC_OPAD);
  for (i=0; i<HASH_LENGTH; i++) write(innerHash[i]);

  return result();
}

#if defined(SHA256_LINUX)
    size_t Sha256Class::write_L(const char *str){
        if (str == NULL) return 0;

        return write_L((const uint8_t *)str, strlen(str));
    }   

    size_t Sha256Class::write_L(const uint8_t *buffer,size_t size){
        size_t n = 0;

        while (size--){
            n +=write(*buffer++);
        }

        return n;
    }

    size_t Sha256Class::print(const char *str){
        return write_L(str);
    }

    double Sha256Class::millis(){
        gettimeofday(&tv, NULL);

        return (tv.tv_sec + 0.000001 * tv.tv_usec);
    }
#endif

Sha256Class Sha256;

我如何从我的 Arduino 代码中调用它是这样的：

uint8_t* hash;
uint32_t a;
unsigned long ms;
Serial.println("Test: RFC4231 4.2");
Serial.println("Expect:b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7");
Serial.print("Result:");
ms = micros();
Sha256.initHmac(hmacKey1,20);
Sha256.print("Hi There");
printHash(Sha256.resultHmac());
Serial.print(" Hash took : ");
Serial.print((micros() - ms));
Serial.println(" micros");
Serial.println();

我想要做的是将 Sha256.print 重命名为 Sha256.Msg。我试图将 class Sha256Class : public Print 重命名为 class Sha256Class : public Msg 但这没有用。我还引用了任何名为 print 的内容并将其重命名为 Msg - 仍然无法正常工作。

Answer 1

您应该只需要更改头文件中原型的名称，然后更改 cpp 文件中的实现定义的名称，最后记住在您使用它的地方更改名称。

.h:

size_t print(const char* str); to size_t Msg(const char * str)

.cpp:

size_t Sha256Class::print(const char *str){
    return write_L(str);
}

to

size_t Sha256Class::Msg(const char *str){
    return write_L(str);
}

arduino 文件：

uint8_t* hash;
uint32_t a;
unsigned long ms;
Serial.println("Test: RFC4231 4.2");
Serial.println("Expect:b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7");
Serial.print("Result:");
ms = micros();
Sha256.initHmac(hmacKey1,20);
/* change from Sha256.print("Hi There") to */
Sha256.Msg("Hi There");
printHash(Sha256.resultHmac());
Serial.print(" Hash took : ");
Serial.print((micros() - ms));
Serial.println(" micros");
Serial.println();

但是，由于您在头文件中的原型周围有一个#if defined(SHA256_LINUX)，因此它可能无法声明为Msg(const char *str) 而不是print(const char *str)，因此最好的解决方案是保留打印功能并创建一个第二种方法做同样的事情。

回应评论。

.h:

// Add this somewhere in the code wherever you see fit
size_t Msg(const char * str);

.cpp:

//Add this somewhere in the cide wherever you see fit
size_t Sha256Class::Msg(const char *str){
    return write_L(str);
}

在 arduino 文件中，只需使用新名称 Sha256.Msg("Hi There"); 调用该函数即可。