找不到段错误。在任何一种情况下都发生在第一次打印之前

Question

包括 main，然后是十六进制和二进制转储的实现，我主要关心的是 main。代码在 C 中。它编译没有错误。我被告知要添加更多详细信息，因为该帖子主要是代码，但我认为我明白了我的意思。我正在寻找导致段错误的原因。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "xbd.h"
#include "xbd.c"

int main(int argc, char *argv[]){
    int i;
    int counter = 0;
    char *addy;
    char buffer[16];

    //If the user wishes for binary output command arg 2 will be '-b'
    if(strcmp(argv[1], "-b") == 0){
        FILE *f = fopen(argv[2], "r");
        addy = (char*) f;
        //Check for valid file
        if(f == NULL){
            printf("Error: File Empty.\n");
            return(-1);
        }
        //print starting address, faults before this print
        printf("%p: ", (void*)&f);
        while((i = fgetc(f)) != EOF){
            //While there are contents in the file, dump in binary groups of 6 chars
            if(counter == 6){
                //print human readable string here
                printf(" ");
                for(int i = 0; i < 6; i++){
                    printf("%s", buffer[i]);
                }
                printf("\n");
                printf("%p: ", (void*)&addy);
                counter = 0;
            }
            buffer[counter] = binForm(i);
            counter++;
            addy++;
        }
        fclose(f);
    }
    //If not binary, output will be in Hex
    else{
        FILE *f = fopen(argv[1], "r");
        //addy = (char*) f;
        //Check for valid file
        if(f == NULL){
            printf("Error: File Empty.\n");
            return(-1);
        }
        //Print starting address, faults before this print
        printf("%p: ", (void*)&f);
        while((i = fgetc(f)) != EOF){
            //While file has contents, dump in hex groups of 16 chars
            if(counter == 16){
                printf(" ");
                //print human readable string here
                for(int i = 0; i < 16; i++){
                    printf("%s", buffer[i]);
                }
                printf("\n");
                printf("%p: ", (void*)&addy);
                counter = 0;
            }
            if(counter%2 == 1){
                buffer[counter] = hexForm(i);
                printf(" ");
            }
            else{
                buffer[counter] = hexForm(i);
            }
            counter++;
            addy++;
        }
        fclose(f);
    }
}

char hexForm(int current_byte){
    //Print hex digits for one byte
    printf("%X", current_byte);
    //If unprintable, convert to '.'
    if(current_byte < 33)
        current_byte = 46;
    return (char)current_byte;
}
char binForm(int current_byte){
    //Print binary digits for one byte
    while (current_byte) {
    if (current_byte & 1)
        printf("1");
    else
        printf("0");

    current_byte >>= 1;
    }
    //If unprintable, convert to '.'
    if(current_byte < 33)
        current_byte = 46;
    return (char)current_byte;
}

为什么会报错？我试着评论一些早期的东西，看看它是否通过，但前几行代码导致段错误。该程序的目的是读取文件，然后根据命令行参数“-b”将文本更改为十六进制或二进制编码输出。

Answer 1

我清理了你的编译器警告。似乎代码现在按预期工作。将来，清理编译器警告并学习使用 gdb 或其他调试器。

此外，在使用 argv[] 之前，您必须检查以确保在命令行上实际提供了足够的参数。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

char hexForm(int current_byte);
char binForm(int current_byte);



int main(int argc, char *argv[]){
    int i;
    int counter = 0;
    char *addy;
    char buffer[16];

    if(argc < 2 )  /* the actual correct usage here is left up to OP */
    {
        printf("Invalid parameters\n")
        return(0);
    }


    //If the user wishes for binary output command arg 2 will be '-b'
    if(strcmp(argv[1], "-b") == 0){
        FILE *f = fopen(argv[2], "r");
        addy = (char*) f;
        //Check for valid file
        if(f == NULL){
            printf("Error: File Empty.\n");
            return(-1);
        }
        //print starting address, faults before this print
        printf("%p: ", (void*)&f);
        while((i = fgetc(f)) != EOF){
            //While there are contents in the file, dump in binary groups of 6 chars
            if(counter == 6){
                //print human readable string here
                printf(" ");
                for(int i = 0; i < 6; i++){
                    printf("%c", buffer[i]);
                }
                printf("\n");
                printf("%p: ", (void*)&addy);
                counter = 0;
            }
            buffer[counter] = binForm(i);
            counter++;
            addy++;
        }
        fclose(f);
    }
    //If not binary, output will be in Hex
    else{
        FILE *f = fopen(argv[1], "r");
        //addy = (char*) f;
        //Check for valid file
        if(f == NULL){
            printf("Error: File Empty.\n");
            return(-1);
        }
        //Print starting address, faults before this print
        printf("%p: ", (void*)&f);
        while((i = fgetc(f)) != EOF){
            //While file has contents, dump in hex groups of 16 chars
            if(counter == 16){
                printf(" ");
                //print human readable string here
                for(int i = 0; i < 16; i++){
                    printf("%c", buffer[i]);
                }
                printf("\n");
                printf("%p: ", (void*)&addy);
                counter = 0;
            }
            if(counter%2 == 1){
                buffer[counter] = hexForm(i);
                printf(" ");
            }
            else{
                buffer[counter] = hexForm(i);
            }
            counter++;
            addy++;
        }
        fclose(f);
    }
}

char hexForm(int current_byte){
    //Print hex digits for one byte
    printf("%X", current_byte);
    //If unprintable, convert to '.'
    if(current_byte < 33)
        current_byte = 46;
    return (char)current_byte;
}
char binForm(int current_byte){
    //Print binary digits for one byte
    while (current_byte) {
    if (current_byte & 1)
        printf("1");
    else
        printf("0");

    current_byte >>= 1;
    }
    //If unprintable, convert to '.'
    if(current_byte < 33)
        current_byte = 46;
    return (char)current_byte;
}