C 无法理解为什么程序在两次while循环迭代后崩溃?
我正在编写下面的程序来解析文本文件(附件),但经过几次while循环迭代后,它一直崩溃,或者似乎存储文件内容的缓冲区被破坏了C 无法理解为什么程序在两次while循环迭代后崩溃?,c,text-files,C,Text Files,我正在编写下面的程序来解析文本文件(附件),但经过几次while循环迭代后,它一直崩溃,或者似乎存储文件内容的缓冲区被破坏了 #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> char * pick_question(char *, char, int); char * print_answer(char *, char, int); int
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
char * pick_question(char *, char, int);
char * print_answer(char *, char, int);
int no_of_questions(char*, char);
void clear();
int debug = 0;
int main(int argc, char* argv[])
{
system("cmd /c chcp 1252");
// system("cmd /c chcp 65001");
if (argc < 2)
{
perror("Please enter a filename!\n");
exit(0);
}
if (argc > 2)
{
debug = atoi(argv[2]);
}
char const* const fileName = argv[1];
FILE* file = fopen(fileName, "r");
if (!file)
{
perror("Unable to read file!\n");
exit(0);
}
else
{
if (debug == 1)
{
printf("File opened successfully\n");
}
}
static char *buffer;
int fileSz;
fseek(file, 0, SEEK_END);
fileSz = ftell(file);
fseek(file, 0, SEEK_SET);
buffer = (char*) malloc((fileSz + 1) * sizeof(char));
if (!buffer)
{
perror("Unable to allocate buffer!");
exit(0);
}
fread(buffer, sizeof(char), fileSz, file);
while (1)
{
time_t t;
srand((unsigned) time(&t));
int sub = rand() % 5 + 1;
char del;
switch (sub)
{
case 1:
del = 'A';
break;
case 2:
del = 'B';
break;
case 3:
del = 'C';
break;
case 4:
del = 'D';
break;
case 5:
del = 'E';
}
int nrOfQues = no_of_questions(buffer, del);
if (nrOfQues == 0)
{
perror("main(): no_of_questions() returned 0. Unsupported text structure in file or incorrect file encoding!");
fclose(file);
exit(0);
}
int qNo = rand() % nrOfQues + 1;
char *ques = pick_question(buffer, del, qNo);
if (ques)
{
printf("\n\n");
puts(ques);
printf("\n\n");
}
else
{
perror("main(): pick_question() returned NULL. Unsupported text structure in file!");
fclose(file);
exit(0);
}
printf("\n\n");
printf("Do you want to see the answer(y/n)?");
char ans, repeat;
scanf("%c", &ans);
if ( ans == 'Y' || ans == 'y')
{
char *ans = print_answer(buffer, del, qNo);
if (ans)
{
printf("\n\n");
puts(ans);
printf("\n\n");
}
else
{
printf("\n\n");
perror("main(): print_answer() returned NULL. Unsupported text structure in file!");
fclose(file);
exit(0);
}
}
printf("Do you want to try more questions (y/n)?");
clear();
scanf("%c", &repeat);
if (repeat == 'N' || repeat == 'n')
{
break;
}
clear();
}
printf("\n\n");
printf("******** Thank you for using TULE Master! ********");
printf("\n\n");
fclose(file);
return 0;
}
char * pick_question(char * buffer, char sub, int qNo)
{
char tmpBuff[20];
char tmpBuff2[20];
const char * searchStr = "FRÅGA";
const char * searchStr2 = "A 1 SVAR:";
const char * searchStr3 = "*****************************************";
char *pStr, *currPos, *nStr, *tmpStr, *tmpStr2;
currPos = buffer;
int count = snprintf(tmpBuff, 20, "FRÅGA %c %d", sub, qNo);
if (count >= 0 || count < 20)
{
if (debug)
{
printf("tmpBuff is %s\n", tmpBuff);
}
currPos = strstr(currPos, tmpBuff);
if (currPos)
{
pStr = currPos;
nStr = currPos + 1;
nStr = strstr(nStr, searchStr);
if (!nStr)
{
nStr = currPos;
nStr = strstr(nStr, searchStr2);
if (!nStr)
{
printf("pick_qestion(): nStr is NULL. Unsupported "
"text structure");
return NULL;
}
}
// Check if it is a scenario based question
count = snprintf(tmpBuff2, 20, "FRÅGA %c %d", sub, qNo-1);
if (count >= 0 || count < 20)
{
tmpStr = strstr(buffer, tmpBuff2);
tmpStr2 = strstr(tmpStr, searchStr3);
if (tmpStr < tmpStr2 && tmpStr2 < pStr)
{
pStr = tmpStr2;
}
}
int qLen = nStr - pStr;
char *ques = malloc(sizeof(char) * (qLen+1));
snprintf(ques,qLen,"%s", pStr);
return ques;
}
else
{
printf("pick_qestion(): string \"FRÅGA\" not found in file!");
return NULL;
}
}
printf("pick_qestion(): snprintf was not successful!");
return NULL;
}
char * print_answer(char * buffer, char sub, int qNo)
{
char tmpBuff[20];
char *pStr, *currPos, *nStr;
int count = snprintf(tmpBuff, 20, "%c %d SVAR:", sub, qNo);
if (count >= 0 || count < 20)
{
currPos = strstr(buffer, tmpBuff);
if (!currPos)
{
printf("print_answer(): string \"SVAR\" not found in file!");
}
pStr = currPos;
nStr = currPos + 1;
char tmpBuff2[20];
int count = snprintf(tmpBuff2, 20, "%c %d SVAR:", sub, qNo+1);
if (count < 0 || count >= 20)
{
printf("print_answer(): snprint was not successful!");
return NULL;
}
nStr = strstr(nStr, tmpBuff2);
if (!nStr)
{
nStr = buffer + strlen(buffer);
}
int ansLen = nStr - pStr;
char *ans = malloc(sizeof(char) * (ansLen+1));
snprintf(ans, ansLen, "%s", pStr);
return ans;
}
printf("print_answer(): snprint was not successful!");
return NULL;
}
int no_of_questions(char *buffer, char sub)
{
char tmpBuff[20];
char *currPos, *pStr;
int count = snprintf(tmpBuff, 20, "FRÅGA %c", sub);
if (count >= 0 || count < 20)
{
if (debug)
{
printf("tmpBuff is %s\n", tmpBuff);
}
currPos = strstr(buffer, tmpBuff);
while (currPos != NULL)
{
pStr = currPos;
currPos = currPos + 1;
currPos = strstr(currPos, tmpBuff);
}
if (pStr != buffer)
{
pStr += 9;
char tmpBuff2[20];
memcpy(tmpBuff2, pStr, 2);
if (debug)
{
printf("No. of questions for %c DEL is are %d\n", sub,
atoi(tmpBuff2));
}
return atoi(tmpBuff2);
}
return 0;
}
return 0;
}
void clear()
{
int c;
while ((c = getchar()) != '\n' && c != EOF) { }
}
#包括
#包括
#包括
#包括
char*选择问题(char*,char,int);
字符*打印答案(字符*,字符,整数);
问题的整数编号(字符*,字符);
无效清除();
int-debug=0;
int main(int argc,char*argv[])
{
系统(“cmd/c chcp 1252”);
//系统(“cmd/c chcp 65001”);
如果(argc<2)
{
perror(“请输入文件名!\n”);
出口(0);
}
如果(argc>2)
{
debug=atoi(argv[2]);
}
char const*const fileName=argv[1];
FILE*FILE=fopen(文件名,“r”);
如果(!文件)
{
perror(“无法读取文件!\n”);
出口(0);
}
其他的
{
如果(调试==1)
{
printf(“文件已成功打开\n”);
}
}
静态字符*缓冲区;
int-fileSz;
fseek(文件,0,SEEK_END);
fileSz=ftell(文件);
fseek(文件,0,搜索集);
buffer=(char*)malloc((fileSz+1)*sizeof(char));
如果(!缓冲区)
{
perror(“无法分配缓冲区!”);
出口(0);
}
fread(buffer,sizeof(char),fileSz,file);
而(1)
{
时间;
srand((未签名)时间(&t));
int sub=rand()%5+1;
查尔德尔;
开关(sub)
{
案例1:
del='A';
打破
案例2:
del='B';
打破
案例3:
del='C';
打破
案例4:
del='D';
打破
案例5:
del='E';
}
int nrOfQues=没有问题(缓冲区,del);
如果(nrOfQues==0)
{
perror(“main():没有任何问题()返回0。文件中的文本结构不受支持或文件编码不正确!”);
fclose(文件);
出口(0);
}
int qNo=rand()%nrOfQues+1;
char*ques=选择问题(缓冲区、del、qNo);
如果(问题)
{
printf(“\n\n”);
售股权证;
printf(“\n\n”);
}
其他的
{
perror(“main():pick_question()返回NULL。文件中不支持的文本结构!”);
fclose(文件);
出口(0);
}
printf(“\n\n”);
printf(“您想看到答案(是/否)?”;
char ans,重复;
scanf(“%c”和“&ans”);
if(ans=='Y'| | ans=='Y')
{
char*ans=打印回答(缓冲区、del、qNo);
如果(ans)
{
printf(“\n\n”);
出售(ans);
printf(“\n\n”);
}
其他的
{
printf(“\n\n”);
perror(“main():print_answer()返回NULL。文件中不支持的文本结构!”);
fclose(文件);
出口(0);
}
}
printf(“您想尝试更多问题(是/否)?”;
清除();
scanf(“%c”,重复(&R));
如果(重复=='N'| |重复=='N')
{
打破
}
清除();
}
printf(“\n\n”);
printf(“*******感谢您使用TULE Master!*******”);
printf(“\n\n”);
fclose(文件);
返回0;
}
字符*选取问题(字符*缓冲区、字符子区、整数qNo)
{
char-tmpBuff[20];
煤焦tmpBuff2[20];
const char*searchStr=“FRÅGA”;
const char*searchStr2=“A 1 SVAR:”;
const char*searchStr3=“*************************************************”;
字符*pStr、*currPos、*nStr、*tmpStr、*tmpStr2;
currPos=缓冲区;
int count=snprintf(tmpBuff,20,“FRÅGA%c%d”,sub,qNo);
如果(计数>=0 | |计数<20)
{
如果(调试)
{
printf(“tmpBuff是%s\n”,tmpBuff);
}
currPos=strstr(currPos,tmpBuff);
if(currPos)
{
pStr=currPos;
nStr=当前位置+1;
nStr=STRSTRSTR(nStr,搜索STR);
如果(!nStr)
{
nStr=currPos;
nStr=strstr(nStr,搜索STR2);
如果(!nStr)
{
printf(“pick_qestion():nStr为空。不受支持”
“文本结构”);
返回NULL;
}
}
//检查是否是基于场景的问题
计数=snprintf(tmpBuff2,20,“FRÅGA%c%d”,sub,qNo-1);
如果(计数>=0 | |计数<20)
{
tmpStr=strstr(缓冲器,tmpBuff2);
tmpStr2=strstrstr(tmpStr,searchStr3);
如果(tmpStr=0 | |计数<20)
{
currPos=strstr(缓冲器,tmpBuff);
如果(!currPos)
{
printf(“print_answer():在文件中找不到字符串\“SVAR\”);
}
pStr=currPos;
nStr=当前位置+1;
煤焦tmpBuff2[20];
int count=snprintf(tmpBuff2,20,“%c%d SVAR:”,sub,qNo+1);
如果(计数<0 | |计数>=20)
{
printf(“print_answer():snprint未成功!”);
返回NULL;
}
nStr=strstr(nStr,tmpBuff2)