Add read portion of file

src/util.c

@@ -53,3 +53,27 @@ char *read_file(char *filepath, int *len) {
 
     return content;
 }
+
+char *read_file_portion(char *filepath, int size, int rank, int *portion_len) {
+    FILE *f = fopen(filepath, "r");
+    fseek(f, 0, SEEK_END);
+    int total_len = ftell(f) - 1;
+
+    int len = total_len / size;
+
+    int start_point = rank * len;
+    int end_point = start_point + len;
+    if (rank + 1 == size)
+        end_point += total_len % size;
+
+    *portion_len = end_point - start_point;
+    char *content = (char *) malloc(sizeof(char) * (*portion_len));
+
+    fseek(f, start_point, SEEK_SET);
+    fread(content, 1, *portion_len, f);
+    fclose(f);
+
+    content[*portion_len] = '\0';
+
+    return NULL;
+}

src/util.h

@@ -11,4 +11,6 @@ int sum_array(int *, int);
 
 char *get_text_file(int argc, char **argv);
 
+char *read_file_portion(char *filepath, int size, int rank, int *portion_len);
+
 #endif //KMP_UTIL_H