Introduction

The implementation of a "Queue" and a "Stack" based on a "Advanced Singly Linked List".

Assignment Objective

In this assignment an Abstract Data Type of an "Advanced Singly Linked List" shall be implemented against the defined common interface of a list. This interface is declared within file 'list.h'. It is intended to be used by applications or other libraries and aims to abstract the 'list' functionality as far as possible.

Based on the implementation of that list, the two major goals, 'Queue' and 'Stack' shall be implemented.

The term 'advanced' in 'Advanced Singly Linked List' refers to the members of the list data: the list shall have

• the pointer to the list head node,
• the pointer to the list tail, and
• the size as its members.

Configuration

There is no configuration required.

Assignment

The 'Advanced Singly Linked List' shall be implemented in file 'advanced_singly_linked_list.c'. The corresponding header file includes the common interface 'list.h' but does not add functions by its own.

The 'Queue' shall implement the interface given in 'queue.h' in file 'queue.c'. It shall make use of the linked list.

The 'Stack' shall implement the interface given in 'stack.h' in file 'stack.c'. It shall make use of the linked list.

The library 'allocator' is provided for memory allocation functionality that integrates with unit testing. Behind the facade, allocats memory dynamically similar to malloc. Allocated memory must be freed when it is not used anymore. The 'allocator' library must be used for memory alloction operations, otherwise unit tests will fail.

1. Implement 'advanced_singly_linked_list.c' against interface indirectly declared in 'list.h': Note that some functions in list.h are commented. Those functions are not required for implementing Queue or Stack. It is allowed to reuse the implementation of the 'simple_singly_linked_list' of an earlier assignment and turn it into an advanced singly linked list. Insertion at head and tail as well removal at head MUST have O(1)!

   Make the program and tests compile: Implement all functions in all relevant files declared in the headers EMTPY (return nothing, 0, false, ... as required).

   • All unit tests shall run but FAIL after this step
   • –COMMIT–
2. Implement the empty functions to make the unit tests pass one by one.
   • Because unit tests depend on more than one function, it is a good idea to implement all obtain, release, and get_size functions before running the tests.
   • The purpose of a function is specified as API documentation within the header files.
   • Obey comments in source files. Run the unit tests frequently and fix failures.
   • –COMMIT– after each implemented function.

Main driver is not required in this assignment.

Notes

1. Again: Earlier implemenation of 'simple singly linked list‘ may be reused but MUST be transformed into an 'advanced singly linked list’.
2. make cleantest: This new make target for clearing the console, building, and running unit test is available.
3. Sometimes changes are not properly detected by incremental builds. If something very strange happens during compilation, try to run make clean followed by make to start a clean build. This approach is also recommended after everthing is done, because some compiler warning appears only in clean builds.