file_loc.c

#include "main.h"

//char *full_path;


int startsWithForwardSlash(const char *str)
{
  if(str!=NULL || str[0] == '/')
    return (1);
  return (0);
}

char *get_file_loc(char *path, char *file_name)
{
  char *path_copy, *token;
  struct stat file_path;
  char *path_buffer = NULL;

  path_copy = strdup(path);
  token = strtok(path_copy, ":");
  while(token)
  {
    if(path_buffer)
    {
      free(path_buffer);
      path_buffer = NULL;
    }
    path_buffer = malloc(strlen(token) + strlen(file_name) + 2);
    if(!path_buffer)
    {
      perror("Error: Memory Allocation Failed: ");
      exit(EXIT_FAILURE);
    }
    strcpy(path_buffer, token);
    strcat(path_buffer, "/");
    strcat(path_buffer, file_name);
    strcat(path_buffer, "\0");
    if(stat(path_buffer, &file_path) ==0 && access(path_buffer, X_OK)==0)
    {
      free(path_copy);
      return (path_buffer);
    }
    token = strtok(NULL, ":");
  }
  free(path_copy);
  if(path_buffer)
    free(path_buffer);
  return (NULL);
}




char *get_file_path(char *file_name)
{
  char *path = getenv("PATH");
  char *full_path;
  if(startsWithForwardSlash(file_name) && access(file_name, X_OK) ==0)
    return (strdup(file_name));
  if(!path)
  {
    perror("Path not found");
    return (NULL);
  }
  full_path = get_file_loc(path, file_name);
  if(full_path == NULL){
    write(2, file_name, strlen(file_name));
    write(2, ": command not found \n", 21);
    return (NULL);
  }
  return (full_path);
}