第四章计算器程序部分代码，结合练习

为了练习多文件组织编程，同时为了能和后面学习的内容结合起来，这套程序改了很多次，至今还有部分功能未实现。

这套主要由main.c && atof.c && stack.c && getch.c && getop.c 构成,头文件share.h对所有函数及共享变量或者外部变量声明。

share.h

#ifndef SHARE_H_INCLUDED#define SHARE_H_INCLUDED#define MAXOP 100 // the max length of character#define NUMBER '0' //label a digit#define BUFFERSIZE 100 //the max size of input buffer#define MAXVOLUME 1000 //maximun dept of stacktypedef struct { //definition of stack  double data[MAXVOLUME]; //volume of stack  int sp; //top pointer of stack} SqStack;void InitStack(SqStack *s); //stack.cbool Push(SqStack *s, double i); //stack.cbool Pop(SqStack *s, double *i); //stack.cbool StackEmpty(SqStack (*s)); //stack.cvoid PrintTop(SqStack *s); //stack,cdouble CopyTop(SqStack *s); //stack.cvoid SwapTop(SqStack *s); //stack.cvoid SetStackEmpty(SqStack *s); //stack.cint Getch(void); //getch.cvoid Ungetch(int c); //getch.cint Getop(char s[]); //getop.cdouble Atof(char s[]); //atof.c#endif // SHARE_H_INCLUDED

main.c

#include <stdio.h>#include <math.h>#include <stdlib.h>#include <stdbool.h>#include <ctype.h>#include "share.h"#define MAXOP 100 // the max length of character//practic 4-3int main(void) {  SqStack val;  int type;  double op1;  double op2;  char s[MAXOP];  //char sAfterTransfrom[MAXOP];  InitStack(&val);  while ((type = Getop(s)) != EOF) {    switch (type) {      case NUMBER :        Push(&val, Atof(s));        PrintTop(&val);        break;      case '+' :        Pop(&val, &op2);        Pop(&val, &op1);        Push(&val, op1 + op2);        break;      case '*' :        Pop(&val, &op2);        Pop(&val, &op1);        Push(&val, op1 * op2);        break;      case '-' :        Pop(&val, &op2);        Pop(&val, &op1);        Push(&val, op1 - op2);        break;      case '/' :        Pop(&val, &op2);        Pop(&val, &op1);        if (op2 != 0.0)          Push(&val, op1 / op2);        else          printf("error: zero divisor\n");        break;      case '%' : //*********practic 4-3********        Pop(&val, &op2);        Pop(&val, &op1);        if (op2 != 0.0)          Push(&val, (double)((int)op1 % (int)op2));        else          printf("error: zero divisor\n");        break;      case '\n' :        Pop(&val, &op2);        printf("\t%.8g\n", op2);        break;      case '\0' :        Pop(&val, &op2);        printf("\t%.8g\n", op2);        break;      default :        printf("error: unknown command %s\n", s);        break;    }  }  return 0;}

atof.c

#include <stdio.h>#include <ctype.h>#include <math.h>#include <stdbool.h>#include "share.h"double Atof(char s[]) {  double val, power;  int i, sign, index;  char index_sign = '+';  for (i = 0; isspace(s[i]); i++) {}  sign = (s[i] == '-') ? -1 : 1;  if (s[i] == '+' || s[i] == '-')    i++;  for (val = 0.0; isdigit(s[i]); i++)    val = 10.0 * val + (s[i] - '0');  if (s[i] == '.')    i++;  for (power = 1.0; isdigit(s[i]); i++) {    val = 10.0 * val + (s[i] - '0');    power *= 10.0;  }  if (s[i] == 'e' || s[i] == 'E') {    ++i;    if ( !(isdigit(s[i])) ) {      index_sign = (s[i] == '-') ? '-' : '+';      ++i;    }    for (index = 0; isdigit(s[i]); i++)      index = 10 * index + (s[i] - '0');    if (index_sign == '+')      return sign * val / power * pow(10.0, index);    else      return sign * val / power / pow(10.0, index);  }  return sign * val / power;}

stack.c

#include <stdio.h>#include <stdbool.h>#include "share.h"void InitStack(SqStack *s) { //initialization of stack  (*s).sp = -1;}bool Push(SqStack *s, double i) {//push element of stack  if ((*s).sp < MAXVOLUME) {    (*s).data[++(*s).sp] = i;    return true;  }  else {    printf("stack is full!\n");    return false;  }}bool Pop(SqStack *s,double *i) {//pop element of stack  if ((*s).sp >= 0) {    *i = (*s).data[(*s).sp--];    return true;  }  else {    printf("\nstack is empty!\n");    return false;  }}bool StackEmpty(SqStack (*s)) { //checks if stack is empty  if ((*s).sp == -1) return true;  return false;}//****************4-4**********void PrintTop(SqStack *s) {  printf("the Top of Stack is %6.3f\n", (*s).data[(*s).sp]);}//***************4-4***********double CopyTop(SqStack *s) {  return (*s).data[(*s).sp];}//*****************4-4************void SwapTop(SqStack *s) {  char temp_1;  char temp_2;  temp_1 = (*s).data[((*s).sp)--];  temp_2 = (*s).data[(*s).sp];  (*s).data[(*s).sp] = temp_1;  ++((*s).sp);  (*s).data[(*s).sp] = temp_2;}//***********************4-4*************void SetStackEmpty(SqStack *s) {// set current stack as empty stack  if ((*s).sp == -1) return;  while ((*s).sp != -1) {    (*s).data[(*s).sp--] = '\0';  }}/*int main(void) {  SqStack s;  int input_temp;  int output_temp;  InitStack(&s);  while ((input_temp = getchar()) != EOF) {    if(Push(&s, input_temp))      continue;    else      break;  }  while (Pop(&s, &output_temp)) {      putchar(output_temp);  }}*/

getch.c

#include <stdio.h>#include <stdbool.h>#include "share.h"char buf[BUFFERSIZE]; //buffer use for store data of input.int bufp = 0; //point free position in buffer.int Getch(void) {  return (bufp > 0) ? buf[--bufp] : getchar();}void Ungetch(int c) {  if (bufp >= BUFFERSIZE)    printf("Ungetch: too many characters\n");  else    buf[bufp++] = c;  //printf("Ungetch: %s\n", buf);}

getop.c 

#include <stdio.h>#include <ctype.h>#include <stdbool.h>#include "share.h"int Getop(char s[]) {  int i = 0;  int c;  int c_next;  while ((s[0] = c = Getch()) == ' ' || c == '\t')    continue;  //printf("******");  if (c == '\0') printf("\\0\n");  s[1] = '\0';  if (!isdigit(c) && c != '.' && c != '-') {    return c;  }  /*  if (c == '+' ||      c == '-' ||      c == '*' ||      c == '%' ||      c == '/' ||      c == '\n')    return c;  */  if (c == '-') {//4-3    while ((c_next = Getch()) == ' ' || c_next == '.')      continue;    if (c_next == '\n') Ungetch(c_next);    if (isdigit(c_next)) {      c = c_next;      s[++i] = c;    }    else {      return c;    }  }  if (isdigit(c)) {    while (isdigit(s[++i] = c = Getch())) {      continue;    }  }  if (c == '.')    while (isdigit(s[++i] = c = Getch()))      continue;  s[i] = '\0';  if (c != EOF) {    Ungetch(c);  }  return NUMBER;}