1 files changed, 153 insertions, 0 deletions
diff --git a/data_struct.c b/data_struct.c
new file mode 100644
index 0000000..bd551ab
--- /dev/null
+++ b/data_struct.c
@@ -0,0 +1,153 @@
+#include "data_struct.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+void add_new_item(struct file_item **list, struct file_item **entry,
+                  const char *file_name)
+{
+    *entry = malloc(sizeof(struct file_item));
+    if(!*entry) {
+        perror("malloc");
+        exit(1);
+    }
+    (*entry)->filename = malloc(strlen(file_name)+1);
+    if(!(*entry)->filename) {
+        perror("malloc");
+        exit(1);
+    }
+    /* safety */
+    strcpy((*entry)->filename, file_name);
+    (*entry)->next = *list;
+    (*entry)->info_line = NULL;
+    *list = *entry;
+}
+/*
+ * Initialize arg_arrays: allocate memory for directories and files
+ * arrays and zero them
+ */
+void init_arg_arrays(struct arg_arrays *split, int argc)
+{
+    split->dirs = malloc(argc * sizeof(char*));
+    if(!split->dirs) {
+        perror("malloc");
+        exit(1);
+    }
+    split->files = malloc(argc * sizeof(char*));
+    if(!split->files) {
+        perror("malloc");
+        exit(1);
+    }
+
+    memset(split->dirs, 0, argc * sizeof(char*));
+    memset(split->files, 0, argc * sizeof(char*));
+}
+
+void init_item_array(struct file_item_array *arr)
+{
+    arr->array = NULL;
+    arr->length = 0;
+}
+
+static size_t get_list_length(struct file_item *list)
+{
+    size_t counter = 0;
+
+    while(list) {
+        ++counter;
+        list = list->next;
+    }
+    return counter;
+}
+
+void copy_list_to_array(struct file_item *list, struct file_item_array *arr)
+{
+    size_t list_length = get_list_length(list);
+    size_t i;
+
+    arr->array = malloc(list_length * sizeof(struct file_item*));
+    if(!arr->array) {
+        perror("malloc");
+        exit(1);
+    }
+    arr->length = list_length;
+
+    for(i = 0; i < list_length; list = list->next, ++i)
+        arr->array[i] = list;
+}
+
+void free_file_item_array(struct file_item_array *arr, struct file_item **list)
+{
+    size_t i;
+
+    for(i = 0; i < arr->length; ++i) {
+        free(arr->array[i]->filename);
+        free(arr->array[i]->info_line);
+        free(arr->array[i]);
+    }
+    if(arr->array)
+        free(arr->array);
+    arr->array = NULL;
+    arr->length = 0;
+    *list = NULL;
+}
+
+void free_arg_arrays(struct arg_arrays *split)
+{
+    free(split->dirs);
+    free(split->files);
+}
+
+int is_empty_array(const char **paths_array, int argc)
+{
+    int empty_flag = 1;
+    size_t i;
+
+    for(i = 0; i < argc; ++i)
+        if(paths_array[i] != 0) {
+            empty_flag = 0;
+            break;
+        }
+    return empty_flag;
+}
+
+int is_last_arr_element(const char **paths_array, int argc, size_t pos)
+{
+    int last_flag = 1;
+
+    for(++pos ; pos < argc; ++pos)
+        if(paths_array[pos]) {
+            last_flag = 0;
+            break;
+        }
+    return last_flag;
+}
+
+static void swap(struct file_item **prev_element,
+                 struct file_item **next_element)
+{
+    struct file_item *tmp_element = NULL;
+
+    if(prev_element != next_element)
+        if(strcmp((*prev_element)->filename, (*next_element)->filename) > 0) {
+            tmp_element = *prev_element;
+            *prev_element = *next_element;
+            *next_element = tmp_element;
+        }
+}
+
+/*
+ * bubble sort
+ */
+void sort_array_by_names(struct file_item_array *arr)
+{
+    size_t i, j;
+
+    if(arr->length == 1)
+        return;
+
+    for(i = arr->length-1; i > 0; --i)
+        for(j = 1; j <= i; ++j)
+            swap(arr->array+j-1, arr->array+j);
+}