为什么realloc报错Thread 1: signal SIGABRT

Question

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<sys/uio.h>
#include<unistd.h>
#include<fcntl.h>
#include<stdarg.h>


void debug(void);
char * string(const char * );
char * strcats(const char * ,const char * );
char * strspe(const char *, ...);
int isDir(const char *);

int main(void){
    debug();
    return 0;
}

void debug(void){
    char * str = "ssssss";
    str = string("abcdef");
    
    char * hello;
    hello = strspe(str,"hello","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world","world",NULL);
    
    printf("hello: %s   ,Address: %p\n",hello,(char *)hello);
}

char * string(const char * str){
    return strcpy(malloc(strlen(str) * sizeof(char) + sizeof(char)),str);
}

char * strcats(const char * str1,const char * str2){
    int realSize = (int)strlen(str2) * sizeof(char) + (int)strlen(str1) * sizeof(char) + sizeof(char);
    str1 = realloc((char *)str1,realSize);
    strcat((char *)str1,str2);
    return (char *)str1;
}

char * strspe(const char * format, ...)
{
    va_list args;
    const char * argv;
    char * result = string(format);
    //free((char*)format);
    va_start(args, format);
    while((argv = va_arg(args,const char *)) && argv != NULL){
        strcats((char *)result,argv);
    }
    va_end(args);
    return result;
}

int isDir(const char *filename){
    return (access(filename, 0) == 0);
}

这是一段 C 代码，有时运行s，有时不运行并给出错误 Thread 1: signal SIGABRT.

Debug (23028,0x1000ebe00) malloc: *** error for object 0x1007af200: pointer being realloc's d was not allocated Debug (23028,0x1000ebe00) malloc: *** set a breakpoint in malloc_error_break to debug(23028,0x1000ebe00) malloc: *** set a breakpoint in malloc_error_break to debug(23028,0x1000ebe00 (lldb)

并将光标定位到第37行：

str1 = realloc((char *)str1,realSize);

我无法解决问题

Answer 1

问题出在这个循环中：

while((argv = va_arg(args,const char *)) && argv != NULL) {
        strcats((char *)result,argv);
}

strcats 重新分配与 result（名为 str1 的参数）关联的内存，但 realloc 可能会更改地址。您正确 return 新地址但从未使用它，因此 result 永远不会改变。然后在给定的时间，当realloc将数据移动到另一个地方时，前者不再有效，在下一个循环中再次发送错误地址。

更改为：

while((argv = va_arg(args,const char *)) && argv != NULL){
        result = strcats(result,argv);
}

为什么realloc报错Thread 1: signal SIGABRT

Why realloc error Thread 1: signal SIGABRT

c

malloc

realloc