segmentation fault in linux

[hta1984]

i'm coding simple version of 'grep' function.i have a code which works in windows but not in linux.can you look at it and help me?:

 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
 
void print_help(){
        printf("NAME\n");
        printf("      fp - search pattern string in file(s)\n\n");
        printf("SYNOPSIS\n");
        printf("      fp [options] PATTERN FILE\n\n");
        printf("DESCRIPTION\n");
        printf("      fp fp searches given input files (or the files in the given path) for lines\n");
        printf("      containing the given PATTERN (string). By default, fp prints only the matching\n");
        printf("      lines.\n\n");
        printf("OPTIONS\n");
        printf("      --help\n");
        printf("            Output this help message.\n\n");
        printf("      -i, --ignore-case\n");
        printf("            Ignore case. Lowercase letters in the pattern, matches uppercase letters\n");
        printf("            in the file, and vice versa.\n\n");
        printf("      -n, --line-number\n");
        printf("            Precedes each line, containing the PATTERN, by its line number in the\n");
        printf("            file.\n\n");
        printf("      -R, -r, --recursive\n");
        printf("            Read and search all files under each directory represented by FILE string\n");
        printf("            (path string in this case), recursively.\n\n");
        printf("      -w, --word\n");
        printf("            The PATTERN must match a whole word.\n");
}
 
int main(int argc, char *argv[]){
        int i,j;
        int i_control = 0,n_control = 0, r_control = 0, w_control = 0; //controls will be 1 if that parameter is given
        char *path; //file path
        char *pattern; //search pattern
        char *argument; //argv[i]
        char *str; //rest of argument after 2 dashes
 
        printf("Argument count: %d\n",argc);
        for(i = 1; i < argc; i++){ //i!=0 at the beginning,because argv[0]=="fp",we skip it
                argument = (char*)malloc(strlen(argv[i]));
                str = (char*)malloc(strlen(argument)-1);
                strcpy(argument,argv[i]);
                printf("Argument = %s\n",argument);
                if(argument[0] == '-'){
                        printf("argument[0] = %c\n",argument[0]);
                        if(argument[1] == '-'){ //command with 2 dashes
                                printf("argument[1] = %c\n",argument[1]);
                                printf("strlen_argument = %d\n", strlen(argument));
                                for(j = 0; j < strlen(argument)-2; j++){ //program terminates here with segmentation fault
                                        str[j] = argument[j+2];
                                }
                                str[strlen(argument)-2] = '\0';
                                printf("str = %s\n", str);
                                if(strcmp(str,"ignore-case")==0){
                                        i_control = 1;
                                }
                                else if(strcmp(str,"line-number")==0){
                                        n_control = 1;
                                }
                                else if(strcmp(str,"recursive")==0){
                                        r_control = 1;
                                }
                                else if(strcmp(str,"word")==0){
                                        w_control = 1;
                                }
                                else if(strcmp(str,"help")==0){
                                        print_help();
                                }
                        } //if
                        else{ //command with 1 dash
                                for(j = 1; j < strlen(argument); j++){ //j!=0 at the beginning,because argument[0]=='-',we skip it
                                        if(argument[j] == 'i'){
                                                i_control = 1;
                                        }
                                        else if(argument[j] == 'n'){
                                                n_control = 1;
                                        }
                                        else if(argument[j] == 'r' || argument[j] == 'R'){
                                                r_control = 1;
                                        }
                                        else if(argument[j] == 'w'){
                                                w_control = 1;
                                        }
                                } //for
                        } //else
                } //if
                free(argument);
                free(str);
        } //for
/*      pattern = argv[argc-2];
        printf("Pattern: %s\n", pattern);
        path = argv[argc-1];
        printf("Path: %s\n", path);
*/
        return 0;
}
 
 

[hta1984]

as you see i'm not finished yet.i'm working on getting parameters from command line.
sample executions of program:
fp -i -wn --recursive
fp --help
fp --ignore-case -nwR

[horace1]

in your statements

    argument = (char*)malloc(strlen(argv[i]));
    str = (char*)malloc(strlen(argument)-1);
    strcpy(argument,argv[i]);
 

you malloc() str before copying argv[1] into argument

it should be

    argument = (char*)malloc(strlen(argv[i]));
    strcpy(argument,argv[i]);
    str = (char*)malloc(strlen(argument)-1);
 

[hta1984]

thank you very much.it solved my problem