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#ifndef shell_helper_functions
#define shell_helper_functions
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
// You must free the result if result is non-NULL.
char *str_replace(char *orig, char *rep, char *with) {
char *result; // the return string
char *ins; // the next insert point
char *tmp; // varies
int len_rep; // length of rep (the string to remove)
int len_with; // length of with (the string to replace rep with)
int len_front; // distance between rep and end of last rep
int count; // number of replacements
// sanity checks and initialization
if (!orig || !rep)
return NULL;
len_rep = strlen(rep);
if (len_rep == 0)
return NULL; // empty rep causes infinite loop during count
if (!with)
with = "";
len_with = strlen(with);
// count the number of replacements needed
ins = orig;
for (count = 0; (tmp = strstr(ins, rep)); ++count) {
ins = tmp + len_rep;
}
tmp = result = malloc(strlen(orig) + (len_with - len_rep) * count + 1);
if (!result)
return NULL;
// first time through the loop, all the variable are set correctly
// from here on,
// tmp points to the end of the result string
// ins points to the next occurrence of rep in orig
// orig points to the remainder of orig after "end of rep"
while (count--) {
ins = strstr(orig, rep);
len_front = ins - orig;
tmp = strncpy(tmp, orig, len_front) + len_front;
tmp = strcpy(tmp, with) + len_with;
orig += len_front + len_rep; // move to next "end of rep"
}
strcpy(tmp, orig);
return result;
}
char *basename(char *path_in)
{
char *token = NULL;
char *lastToken = NULL;
char *basePath;
basePath = (char *)malloc(sizeof(char) * (strlen(path_in) + 1));
if (!basePath) {
fprintf(stderr, "lsh: allocatin error\n");
exit(EXIT_FAILURE);
}
strcpy(basePath, path_in);
token = strtok(basePath, "/");
while (token != NULL) {
lastToken = token;
token = strtok(NULL, "/");
}
if (lastToken == NULL){
free(basePath);
return NULL;
}
char *ret_str = (char*)malloc(sizeof(char)*strlen(lastToken)+1);
if (!ret_str) {
fprintf(stderr, "lsh: allocation error\n");
exit(EXIT_FAILURE);
}
strcpy(ret_str,lastToken);
free(basePath);
return ret_str;
}
#endif
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