Add the last exercises

2025-09-06 23:31:03 +02:00
parent ba0d496a3c
commit 780996458b
173 changed files with 4329 additions and 161 deletions
@@ -6,25 +6,25 @@
 Completed course from
 [[https://www.boot.dev/courses/learn-memory-management-c][boot.dev]].

-The exercises from the course have been worked out in this repo.
-This is my way of having the "certificate" for free.
+The exercises from the course have been worked out in this repository.
+This is my way of obtaining the "certificate" for free.
 The first the 3 chapters of the course can be done interactively on the website.

 [[./bootdev-c.png]]

 If you're reading this with the intention of completing the exercises yourself,
 you can find each exercise is in its own directory inside of the =src= directory.
-Remove all the files that are not called =main.c= and recreate them from the
-exercises on the boot.dev website as you go through them, so you won't get spoiled.
+Remove all the files that each exercise mentions you should modify, as you go
+through them. Then recreate the files from the exercise, so you won't get spoiled.

-Note:
+Notes:
 - In order to verify allocations in the unit tests, please use the wrapper
  functions =boot_malloc=, =boot_calloc=, =boot_realloc= and =boot_free= from
  =boot_lib.h= instead of the =stdlib.h= allocation functions
 - In chapter 6 exercise 6, macOS malloc will almost never return a NULL pointer
  due to virtual memory overcommit, so you should check for
  ~size == 1024 * 1024 * 100)~ instead of ~array == NULL~
- In chapter 8, I renamed ~stack_t~ to ~my_stack_t~ due to a =std= naming
+- In chapter 8 and 11, I renamed ~stack_t~ to ~my_stack_t~ due to a =std= naming
  conflict on macOS

 ** Build instructions
@@ -44,72 +44,89 @@ Successful output of all the tests:

 #+BEGIN_SRC sh
 $ make run                                                                                                                                                                                     12:25PM
-[  3%] Built target munit
-[  6%] Built target 9-8-length
-[  7%] Built target 4-1-enums
-[  9%] Built target 4-2-non-default-values
-[ 12%] Built target 4-3-switch-case
-[ 14%] Built target 4-4-sizeof-enum
-[ 17%] Built target 5-1-union
-[ 19%] Built target 5-2-memory-layout
-[ 21%] Built target 5-3-5-4-union-size
-[ 23%] Built target 5-5-helper-fields
-[ 25%] Built target 6-1-the-stack
-[ 27%] Built target 6-2-why-a-stack
-[ 29%] Built target 6-3-stack-overflow
-[ 31%] Built target 6-4-pointers-to-the-stack
-[ 34%] Built target 6-5-the-heap
-[ 37%] Built target 6-6-malloc
-[ 40%] Built target 6-7-free
-[ 42%] Built target 6-8-big-endian-little-endian
-[ 45%] Built target 7-1-pointer-pointers
-[ 48%] Built target 7-2-array-of-pointers
-[ 51%] Built target 7-3-void-pointers
-[ 54%] Built target 7-4-swapping-integers
-[ 57%] Built target 7-5-swapping-strings
-[ 60%] Built target 7-6-generic-swap
-[ 63%] Built target 8-1-low-level-stack
-[ 66%] Built target 8-2-stack-push
-[ 69%] Built target 8-3-stack-pop
-[ 72%] Built target 8-4-stack-free
-[ 76%] Built target 8-5-dangerous-push
-[ 80%] Built target 8-6-multiple-types
-[ 82%] Built target 9-1-snek-objects
-[ 85%] Built target 9-2-integer
-[ 88%] Built target 9-3-float
-[ 91%] Built target 9-4-string
-[ 94%] Built target 9-5-vector3
-[ 97%] Built target 9-6-arrays
-[100%] Built target 9-7-get-and-set
-Running test suite with seed 0xa13b83c4...
-colors/are_defined                   [ OK    ] [ 0.00000100 / 0.00000300 CPU ]
+[  2%] Built target munit
+[  5%] Built target 11-10-sweep
+[  6%] Built target 04-1-enums
+[  7%] Built target 04-2-non-default-values
+[  9%] Built target 04-3-switch-case
+[ 10%] Built target 04-4-sizeof-enum
+[ 12%] Built target 05-1-union
+[ 13%] Built target 05-2-memory-layout
+[ 15%] Built target 05-3-5-4-union-size
+[ 16%] Built target 05-5-helper-fields
+[ 17%] Built target 06-1-the-stack
+[ 19%] Built target 06-2-why-a-stack
+[ 20%] Built target 06-3-stack-overflow
+[ 21%] Built target 06-4-pointers-to-the-stack
+[ 23%] Built target 06-5-the-heap
+[ 25%] Built target 06-6-malloc
+[ 27%] Built target 06-7-free
+[ 28%] Built target 06-8-big-endian-little-endian
+[ 30%] Built target 07-1-pointer-pointers
+[ 32%] Built target 07-2-array-of-pointers
+[ 33%] Built target 07-3-void-pointers
+[ 35%] Built target 07-4-swapping-integers
+[ 37%] Built target 07-5-swapping-strings
+[ 39%] Built target 07-6-generic-swap
+[ 41%] Built target 08-1-low-level-stack
+[ 42%] Built target 08-2-stack-push
+[ 44%] Built target 08-3-stack-pop
+[ 46%] Built target 08-4-stack-free
+[ 48%] Built target 08-5-dangerous-push
+[ 50%] Built target 08-6-multiple-types
+[ 52%] Built target 09-1-snek-objects
+[ 53%] Built target 09-2-integer
+[ 55%] Built target 09-3-float
+[ 57%] Built target 09-4-string
+[ 59%] Built target 09-5-vector3
+[ 61%] Built target 09-6-arrays
+[ 62%] Built target 09-7-get-and-set
+[ 64%] Built target 09-8-length
+[ 65%] Built target 10-1-garbage-collector
+[ 67%] Built target 10-2-refcounting
+[ 69%] Built target 10-3-increment
+[ 71%] Built target 10-4-decrement-and-free
+[ 73%] Built target 10-5-vectors
+[ 74%] Built target 10-6-arrays
+[ 76%] Built target 10-7-refcounting-review
+[ 77%] Built target 11-01-handling-cycles
+[ 80%] Built target 11-02-pros-and-cons
+[ 82%] Built target 11-03-stack-frames
+[ 85%] Built target 11-04-tracking-objects
+[ 88%] Built target 11-05-free
+[ 91%] Built target 11-06-frame-references
+[ 94%] Built target 11-07-mark-and-sweep
+[ 97%] Built target 11-08-mark
+[100%] Built target 11-09-trace
+Running test suite with seed 0x3d418efb...
+colors/are_defined                   [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
 colors/are_defined_correctly         [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x9c11f043...
-colors/defined                       [ OK    ] [ 0.00000000 / 0.00000000 CPU ]
-colors/defined_vscode                [ OK    ] [ 0.00000000 / 0.00000000 CPU ]
+Running test suite with seed 0x1447c343...
+colors/defined                       [ OK    ] [ 0.00000000 / 0.00000100 CPU ]
+colors/defined_vscode                [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xdac57c79...
+Running test suite with seed 0xba550ddb...
 http/switch_enum                     [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-http/switch_enum_default             [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+http/switch_enum_default             [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
 The size of BigNumbers is 8 bytes
 The size of HttpErrorCode is 4 bytes
-Running test suite with seed 0x85251cb1...
-format/integer                       [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0xba8a2b8d...
+format/integer                       [ OK    ] [ 0.00000200 / 0.00000300 CPU ]
 format/string                        [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-format/integer_nvim                  [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-format/string_nvim                   [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+format/integer_nvim                  [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
+format/string_nvim                   [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
 4 of 4 (100%) tests successful, 0 (0%) test skipped.
 value (set): -420
 err (unset): 4294966876
 value (unset): -1
 err (set): 4294967295
-Running test suite with seed 0xb2bd8586...
-PacketHeader/test_packet_header_size [ OK    ] [ 0.00000100 / 0.00000000 CPU ]
+Running test suite with seed 0xa0f30fc8...
+PacketHeader/test_packet_header_size [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
 PacketHeader/test_tcp_header_fields  [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-PacketHeader/test_field_raw_size     [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-PacketHeader/test_field_to_raw_consistency[ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+PacketHeader/test_field_raw_size     [ OK    ] [ 0.00000100 / 0.00000000 CPU ]
+PacketHeader/test_field_to_raw_consistency[ OK    ] [ 0.00000100 / 0.00000000 CPU ]
 4 of 4 (100%) tests successful, 0 (0%) test skipped.
 ---------------------------------
 Stack pointer offset: 0 bytes
@@ -126,141 +143,246 @@ Stack pointer offset: 0 bytes
 ---------------------------------
 dark roast.

-Running test suite with seed 0x5ed24c16...
-/example/compare                     [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-/example/rand                        [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
+Running test suite with seed 0xbd38a5fa...
+/example/compare                     [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+/example/rand                        [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
 /example/parameters
-  foo=one, bar=red                   [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-  foo=one, bar=green                 [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-  foo=one, bar=blue                  [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-  foo=two, bar=red                   [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
+  foo=one, bar=red                   [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+  foo=one, bar=green                 [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+  foo=one, bar=blue                  [ OK    ] [ 0.00000200 / 0.00000300 CPU ]
+  foo=two, bar=red                   [ OK    ] [ 0.00000300 / 0.00000200 CPU ]
  foo=two, bar=green                 [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
  foo=two, bar=blue                  [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-  foo=three, bar=red                 [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-  foo=three, bar=green               [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-  foo=three, bar=blue                [ OK    ] [ 0.00000100 / 0.00000000 CPU ]
+  foo=three, bar=red                 [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+  foo=three, bar=green               [ OK    ] [ 0.00000300 / 0.00000200 CPU ]
+  foo=three, bar=blue                [ OK    ] [ 0.00000200 / 0.00000300 CPU ]
 11 of 11 (100%) tests successful, 0 (0%) test skipped.
 Size of pool: 10240
 Initial string: snek
 c1: 10, 20
 c2: 30, 40
 c3: 50, 60
-Running test suite with seed 0x08ecbbe7...
-get_full_greeting/test_basic_greeting[ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-get_full_greeting/test_short_buffer  [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+Running test suite with seed 0x4e7eb250...
+get_full_greeting/test_basic_greeting[ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+get_full_greeting/test_short_buffer  [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xd953a05a...
-allocate_scalar_array/test_allocate_scalar_array_size[ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-allocate_scalar_array/test_allocate_scalar_array_values[ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-allocate_scalar_array/test_allocate_scalar_array_zero_multiplier[ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-allocate_scalar_array/test_allocate_too_much[ OK    ] [ 0.00001000 / 0.00000900 CPU ]
+Running test suite with seed 0x98ffe6c3...
+allocate_scalar_array/test_allocate_scalar_array_size[ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+allocate_scalar_array/test_allocate_scalar_array_values[ OK    ] [ 0.00000300 / 0.00000400 CPU ]
+allocate_scalar_array/test_allocate_scalar_array_zero_multiplier[ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+allocate_scalar_array/test_allocate_too_much[ OK    ] [ 0.00001800 / 0.00001800 CPU ]
 4 of 4 (100%) tests successful, 0 (0%) test skipped.
 Allocated 500 lists
-Running test suite with seed 0x026c49ea...
-/example/compare                     [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-/example/rand                        [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+Running test suite with seed 0xd142494f...
+/example/compare                     [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+/example/rand                        [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
 /example/parameters
-  foo=one, bar=red                   [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-  foo=one, bar=green                 [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-  foo=one, bar=blue                  [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-  foo=two, bar=red                   [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-  foo=two, bar=green                 [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-  foo=two, bar=blue                  [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-  foo=three, bar=red                 [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-  foo=three, bar=green               [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-  foo=three, bar=blue                [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
+  foo=one, bar=red                   [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=one, bar=green                 [ OK    ] [ 0.00000600 / 0.00000700 CPU ]
+  foo=one, bar=blue                  [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=two, bar=red                   [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=two, bar=green                 [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+  foo=two, bar=blue                  [ OK    ] [ 0.00000500 / 0.00000600 CPU ]
+  foo=three, bar=red                 [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=three, bar=green               [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+  foo=three, bar=blue                [ OK    ] [ 0.00001100 / 0.00001100 CPU ]
 11 of 11 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xbb38daad...
-allocate_list/create                 [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-allocate_list/overwrite              [ OK    ] [ 0.00000100 / 0.00000000 CPU ]
+Running test suite with seed 0x3b94faee...
+allocate_list/create                 [ OK    ] [ 0.00000500 / 0.00000600 CPU ]
+allocate_list/overwrite              [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x33807c18...
-create_token_pointer_array/test_create_token_pointer_array_single[ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-create_token_pointer_array/test_create_token_pointer_array_multiple[ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-create_token_pointer_array/test_create_token_pointer_array_memory_allocation[ OK    ] [ 0.00000200 / 0.00000200 CPU ]
+Running test suite with seed 0x30623318...
+create_token_pointer_array/test_create_token_pointer_array_single[ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+create_token_pointer_array/test_create_token_pointer_array_multiple[ OK    ] [ 0.00000600 / 0.00000700 CPU ]
+create_token_pointer_array/test_create_token_pointer_array_memory_allocation[ OK    ] [ 0.00000600 / 0.00000600 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x8614a0d1...
-snek_zero_out/test_zero_out_integer  [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-snek_zero_out/test_zero_out_float    [ OK    ] [ 0.00000100 / 0.00000000 CPU ]
-snek_zero_out/test_zero_out_bool     [ OK    ] [ 0.00000000 / 0.00000000 CPU ]
-snek_zero_out/test_zero_out_nonzero_values[ OK    ] [ 0.00000100 / 0.00000000 CPU ]
+Running test suite with seed 0xdb4dc3bb...
+snek_zero_out/test_zero_out_integer  [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+snek_zero_out/test_zero_out_float    [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+snek_zero_out/test_zero_out_bool     [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+snek_zero_out/test_zero_out_nonzero_values[ OK    ] [ 0.00000400 / 0.00000400 CPU ]
 4 of 4 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x2f6f82cf...
-void-pointer/swap_ints               [ OK    ] [ 0.00000000 / 0.00000000 CPU ]
-void-pointer/swap_ints_same          [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+Running test suite with seed 0x1e23c270...
+void-pointer/swap_ints               [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
+void-pointer/swap_ints_same          [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x62099957...
-void-pointer/swap_str                [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-void-pointer/test_swap_str_long      [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0x343e18c2...
+void-pointer/swap_str                [ OK    ] [ 0.00000400 / 0.00000500 CPU ]
+void-pointer/test_swap_str_long      [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x56ef9f75...
-swap/generic_ints                    [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-swap/generic_strings                 [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-swap/generic_struct                  [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
+Running test suite with seed 0x349b3cc2...
+swap/generic_ints                    [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
+swap/generic_strings                 [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+swap/generic_struct                  [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xdf070ee5...
-snekstack/create_stack_small         [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-snekstack/create_stack_large         [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0xcc7f57e3...
+snekstack/create_stack_small         [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+snekstack/create_stack_large         [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xa0778dac...
-snekstack/create_stack               [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-snekstack/push_stack                 [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-snekstack/push_double_capacity       [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+Running test suite with seed 0xb54c2f05...
+snekstack/create_stack               [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+snekstack/push_stack                 [ OK    ] [ 0.00000700 / 0.00000600 CPU ]
+snekstack/push_double_capacity       [ OK    ] [ 0.00000900 / 0.00000900 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x1df97623...
-snekstack/create_stack               [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-snekstack/push_stack                 [ OK    ] [ 0.00000200 / 0.00000300 CPU ]
-snekstack/pop_stack                  [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-snekstack/pop_stack_empty            [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
+Running test suite with seed 0x986e20e8...
+snekstack/create_stack               [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+snekstack/push_stack                 [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+snekstack/pop_stack                  [ OK    ] [ 0.00000600 / 0.00000700 CPU ]
+snekstack/pop_stack_empty            [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
 4 of 4 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xc67f74fb...
-snekstack/create_stack               [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-snekstack/push_stack                 [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-snekstack/pop_stack                  [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+Running test suite with seed 0xf45ae006...
+snekstack/create_stack               [ OK    ] [ 0.00000700 / 0.00000600 CPU ]
+snekstack/push_stack                 [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+snekstack/pop_stack                  [ OK    ] [ 0.00000700 / 0.00000700 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xb607698d...
-snekstack/heterogenous_stack         [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
+Running test suite with seed 0xf83a103b...
+snekstack/heterogenous_stack         [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
 1 of 1 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x4804e928...
-snekstack/multiple_types_stack       [ OK    ] [ 0.00000200 / 0.00000300 CPU ]
+Running test suite with seed 0x53a94d13...
+snekstack/multiple_types_stack       [ OK    ] [ 0.00000800 / 0.00000800 CPU ]
 1 of 1 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xa5a077a3...
-object-integer-def/integer_constant  [ OK    ] [ 0.00000000 / 0.00000100 CPU ]
-object-integer-def/integer_obj       [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0xd977a296...
+object-integer-def/integer_constant  [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+object-integer-def/integer_obj       [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x0a7224ef...
-object-integer/positive              [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-object-integer/zero                  [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-object-integer/negative              [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0x9850a5b5...
+object-integer/positive              [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+object-integer/zero                  [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+object-integer/negative              [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x748c3598...
-object-float/positive                [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-object-float/zero                    [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-object-float/negative                [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0x06edb0c3...
+object-float/positive                [ OK    ] [ 0.00000600 / 0.00000400 CPU ]
+object-float/zero                    [ OK    ] [ 0.00002200 / 0.00001700 CPU ]
+object-float/negative                [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x4632a6a6...
-object-string/copies_value           [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
+Running test suite with seed 0x846fed7d...
+object-string/copies_value           [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
 1 of 1 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x386735e2...
-object-vector/returns_null           [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
-object-vector/multiple_objects       [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-object-vector/same_object            [ OK    ] [ 0.00000100 / 0.00000200 CPU ]
+Running test suite with seed 0x53cf4c00...
+object-vector/returns_null           [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+object-vector/multiple_objects       [ OK    ] [ 0.00000700 / 0.00000700 CPU ]
+object-vector/same_object            [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0x4e6badf5...
-object-array/empty                   [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
-object-array/calloc                  [ OK    ] [ 0.00000100 / 0.00000100 CPU ]
+Running test suite with seed 0x58fd8016...
+object-array/empty                   [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+object-array/calloc                  [ OK    ] [ 0.00000300 / 0.00000400 CPU ]
 2 of 2 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xe9625367...
-object-array/set_and_get             [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-object-array/set_outside             [ OK    ] [ 0.00000200 / 0.00000300 CPU ]
-object-array/get_outside             [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
+Running test suite with seed 0x7f5412f2...
+object-array/set_and_get             [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+object-array/set_outside             [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+object-array/get_outside             [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
 3 of 3 (100%) tests successful, 0 (0%) test skipped.
-Running test suite with seed 0xa7022b54...
-object-length/integer                [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
-object-length/float                  [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-object-length/string                 [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-object-length/vector                 [ OK    ] [ 0.00000200 / 0.00000200 CPU ]
-object-length/array                  [ OK    ] [ 0.00000200 / 0.00000100 CPU ]
+Running test suite with seed 0xa5a5383d...
+object-length/integer                [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+object-length/float                  [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+object-length/string                 [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+object-length/vector                 [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+object-length/array                  [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
 5 of 5 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x2e6f75bf...
+/example/compare                     [ OK    ] [ 0.00000600 / 0.00000400 CPU ]
+/example/rand                        [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+/example/parameters
+  foo=one, bar=red                   [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+  foo=one, bar=green                 [ OK    ] [ 0.00000500 / 0.00000600 CPU ]
+  foo=one, bar=blue                  [ OK    ] [ 0.00000900 / 0.00000800 CPU ]
+  foo=two, bar=red                   [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=two, bar=green                 [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=two, bar=blue                  [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=three, bar=red                 [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+  foo=three, bar=green               [ OK    ] [ 0.00000300 / 0.00000400 CPU ]
+  foo=three, bar=blue                [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+11 of 11 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0xdf462866...
+refcounttest_int_has_refcount        [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
+refcounttest_float_has_refcount      [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x3b906f5c...
+refcount/test_inc_refcount           [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+refcount/test_inc_refcount_more      [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+refcount/test_null_obj               [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+3 of 3 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x6b51ea68...
+refcount/has_refcount                [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+refcount/inc_refcount                [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+refcount/dec_refcount                [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+refcount/free_refcount               [ OK    ] [ 0.00000400 / 0.00000500 CPU ]
+refcount/string_freed                [ OK    ] [ 0.00000500 / 0.00000600 CPU ]
+5 of 5 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0xfcdf2928...
+refcount/has_refcount                [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+refcount/inc_refcount                [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+refcount/dec_refcount                [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+refcount/free_refcount               [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+refcount/string_freed                [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+refcount/vector3                     [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+refcount/vector3-same                [ OK    ] [ 0.00000300 / 0.00000200 CPU ]
+7 of 7 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x2df34e21...
+refcount/array_set                   [ OK    ] [ 0.00000800 / 0.00000800 CPU ]
+refcount/array_free                  [ OK    ] [ 0.00000600 / 0.00000700 CPU ]
+refcount/has_refcount                [ OK    ] [ 0.00000300 / 0.00000300 CPU ]
+refcount/inc_refcount                [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+refcount/dec_refcount                [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+refcount/free_refcount               [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+refcount/string_freed                [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+refcount/vector3                     [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+8 of 8 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x91892c1e...
+/example/compare                     [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+/example/rand                        [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+/example/parameters
+  foo=one, bar=red                   [ OK    ] [ 0.00000500 / 0.00000400 CPU ]
+  foo=one, bar=green                 [ OK    ] [ 0.00000500 / 0.00000500 CPU ]
+  foo=one, bar=blue                  [ OK    ] [ 0.00001100 / 0.00001200 CPU ]
+  foo=two, bar=red                   [ OK    ] [ 0.00000500 / 0.00000600 CPU ]
+  foo=two, bar=green                 [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+  foo=two, bar=blue                  [ OK    ] [ 0.00000300 / 0.00000400 CPU ]
+  foo=three, bar=red                 [ OK    ] [ 0.00000300 / 0.00000400 CPU ]
+  foo=three, bar=green               [ OK    ] [ 0.00000400 / 0.00000400 CPU ]
+  foo=three, bar=blue                [ OK    ] [ 0.00000400 / 0.00000300 CPU ]
+11 of 11 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x0dddaf2c...
+refcount/correctly_free              [ OK    ] [ 0.00000700 / 0.00000700 CPU ]
+1 of 1 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x435b0c66...
+mark-and-sweep/vm                    [ OK    ] [ 0.00000600 / 0.00000700 CPU ]
+mark-and-sweep/vm                    [ OK    ] [ 0.00001400 / 0.00000700 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x85af19f7...
+mark-and-sweep/test_vm_new           [ OK    ] [ 0.00000800 / 0.00000700 CPU ]
+mark-and-sweep/test_vm_new_frame     [ OK    ] [ 0.00000700 / 0.00000600 CPU ]
+mark-and-sweep/test_frames_are_freed [ OK    ] [ 0.00000600 / 0.00000600 CPU ]
+3 of 3 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x1cceaa41...
+mark-and-sweep/test_vm_new           [ OK    ] [ 0.00000800 / 0.00000700 CPU ]
+mark-and-sweep/test_frames_are_freed [ OK    ] [ 0.00000700 / 0.00000700 CPU ]
+mark-and-sweep/test_new_object       [ OK    ] [ 0.00000700 / 0.00000600 CPU ]
+3 of 3 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0xc169d14b...
+mark-and-sweep/test_reference_object [ OK    ] [ 0.00000700 / 0.00000700 CPU ]
+mark-and-sweep/test_frames_are_freed [ OK    ] [ 0.00000700 / 0.00000700 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0xac37539a...
+mark-and-sweep/test_one_ref          [ OK    ] [ 0.00000900 / 0.00000900 CPU ]
+mark-and-sweep/test_multi_ref        [ OK    ] [ 0.00000800 / 0.00000800 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0xaa6df145...
+mark-and-sweep/test_field_exists     [ OK    ] [ 0.00000900 / 0.00000800 CPU ]
+mark-and-sweep/test_marked_is_false  [ OK    ] [ 0.00000600 / 0.00000500 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x22d87982...
+mark-and-sweep/test_single_frame     [ OK    ] [ 0.00000900 / 0.00000900 CPU ]
+mark-and-sweep/test_multi_frame      [ OK    ] [ 0.00001000 / 0.00001100 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x147d09b4...
+mark-and-sweep/test_trace_vector     [ OK    ] [ 0.00000900 / 0.00000900 CPU ]
+mark-and-sweep/test_trace_array      [ OK    ] [ 0.00001200 / 0.00001300 CPU ]
+mark-and-sweep/test_trace_nested     [ OK    ] [ 0.00001700 / 0.00001700 CPU ]
+3 of 3 (100%) tests successful, 0 (0%) test skipped.
+Running test suite with seed 0x93c96b1a...
+mark-and-sweep/test_simple           [ OK    ] [ 0.00000900 / 0.00000800 CPU ]
+mark-and-sweep/test_full             [ OK    ] [ 0.00001900 / 0.00002000 CPU ]
+2 of 2 (100%) tests successful, 0 (0%) test skipped.
 [100%] Built target run
 #+END_SRC
@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "munit.h"
+#include "snekobject.h"
+
+munit_case(RUN, correctly_free, {
+	snek_object_t *first = new_snek_array(1);
+	snek_object_t *second = new_snek_array(1);
+	// refcounts: first = 1, second = 1
+	snek_array_set(first, 0, second);
+	// refcounts: first = 1, second = 2
+	snek_array_set(second, 0, first);
+	// refcounts: first = 2, second = 2
+	refcount_dec(first);
+	refcount_dec(second);
+	assert_int(first->refcount, ==, 1, "Refcount first should be 1");
+	assert_int(second->refcount, ==, 1, "Refcount second should be 1");
+});
+
+int main() {
+	MunitTest tests[] = {
+		munit_test("/correctly_free", correctly_free),
+		munit_null_test,
+	};
+
+	MunitSuite suite = munit_suite("refcount", tests);
+
+	return munit_suite_main(&suite, NULL, 0, NULL);
+}
@@ -0,0 +1,179 @@
+#include "assert.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "bootlib.h"
+#include "snekobject.h"
+
+bool snek_array_set(snek_object_t *snek_obj, size_t index, snek_object_t *value) {
+	if (snek_obj == NULL || value == NULL) {
+		return false;
+	}
+	if (snek_obj->kind != ARRAY) {
+		return false;
+	}
+	if (index >= snek_obj->data.v_array.size) {
+		return false;
+	}
+	refcount_inc(value);
+	if (snek_obj->data.v_array.elements[index] != NULL) {
+		refcount_dec(snek_obj->data.v_array.elements[index]);
+	}
+	snek_obj->data.v_array.elements[index] = value;
+	return true;
+}
+
+void refcount_boot_free(snek_object_t *obj) {
+	switch (obj->kind) {
+	case INTEGER:
+	case FLOAT:
+		break;
+	case STRING:
+		boot_free(obj->data.v_string);
+		break;
+	case VECTOR3: {
+		snek_vector_t vec = obj->data.v_vector3;
+		refcount_dec(vec.x);
+		refcount_dec(vec.y);
+		refcount_dec(vec.z);
+		break;
+	}
+	case ARRAY: {
+		snek_array_t array = obj->data.v_array;
+		for (size_t i = 0; i < array.size; i++) {
+			refcount_dec(array.elements[i]);
+		}
+		boot_free(array.elements);
+		break;
+	}
+	default:
+		assert(false);
+	}
+	boot_free(obj);
+}
+
+snek_object_t *snek_array_get(snek_object_t *snek_obj, size_t index) {
+	if (snek_obj == NULL) {
+		return NULL;
+	}
+
+	if (snek_obj->kind != ARRAY) {
+		return NULL;
+	}
+
+	if (index >= snek_obj->data.v_array.size) {
+		return NULL;
+	}
+
+	return snek_obj->data.v_array.elements[index];
+}
+
+void refcount_inc(snek_object_t *obj) {
+	if (obj == NULL) {
+		return;
+	}
+
+	obj->refcount++;
+	return;
+}
+
+void refcount_dec(snek_object_t *obj) {
+	if (obj == NULL) {
+		return;
+	}
+	obj->refcount--;
+	if (obj->refcount == 0) {
+		return refcount_boot_free(obj);
+	}
+	return;
+}
+
+snek_object_t *_new_snek_object() {
+	snek_object_t *obj = boot_calloc(1, sizeof(snek_object_t));
+	if (obj == NULL) {
+		return NULL;
+	}
+
+	obj->refcount = 1;
+
+	return obj;
+}
+
+snek_object_t *new_snek_array(size_t size) {
+	snek_object_t *obj = _new_snek_object();
+	if (obj == NULL) {
+		return NULL;
+	}
+
+	snek_object_t **elements = boot_calloc(size, sizeof(snek_object_t *));
+	if (elements == NULL) {
+		boot_free(obj);
+		return NULL;
+	}
+
+	obj->kind = ARRAY;
+	obj->data.v_array = (snek_array_t){.size = size, .elements = elements};
+
+	return obj;
+}
+
+snek_object_t *new_snek_integer(int value) {
+	snek_object_t *obj = _new_snek_object();
+	if (obj == NULL) {
+		return NULL;
+	}
+
+	obj->kind = INTEGER;
+	obj->data.v_int = value;
+	return obj;
+}
+
+snek_object_t *new_snek_float(float value) {
+	snek_object_t *obj = _new_snek_object();
+	if (obj == NULL) {
+		return NULL;
+	}
+
+	obj->kind = FLOAT;
+	obj->data.v_float = value;
+	return obj;
+}
+
+snek_object_t *new_snek_string(char *value) {
+	snek_object_t *obj = _new_snek_object();
+	if (obj == NULL) {
+		return NULL;
+	}
+
+	int len = strlen(value);
+	char *dst = boot_malloc(len + 1);
+	if (dst == NULL) {
+		boot_free(obj);
+		return NULL;
+	}
+
+	strcpy(dst, value);
+
+	obj->kind = STRING;
+	obj->data.v_string = dst;
+	return obj;
+}
+
+snek_object_t *new_snek_vector3(
+		snek_object_t *x, snek_object_t *y, snek_object_t *z
+) {
+	if (x == NULL || y == NULL || z == NULL) {
+		return NULL;
+	}
+	snek_object_t *obj = _new_snek_object();
+	if (obj == NULL) {
+		return NULL;
+	}
+	obj->kind = VECTOR3;
+	obj->data.v_vector3 = (snek_vector_t){.x = x, .y = y, .z = z};
+	refcount_inc(x);
+	refcount_inc(y);
+	refcount_inc(z);
+	return obj;
+}
@@ -0,0 +1,52 @@
+#include <stdbool.h>
+#include <stddef.h>
+
+typedef struct SnekObject snek_object_t;
+
+typedef struct {
+	size_t size;
+	snek_object_t **elements;
+} snek_array_t;
+
+typedef struct {
+	snek_object_t *x;
+	snek_object_t *y;
+	snek_object_t *z;
+} snek_vector_t;
+
+typedef enum SnekObjectKind {
+	INTEGER,
+	FLOAT,
+	STRING,
+	VECTOR3,
+	ARRAY,
+} snek_object_kind_t;
+
+typedef union SnekObjectData {
+	int v_int;
+	float v_float;
+	char *v_string;
+	snek_vector_t v_vector3;
+	snek_array_t v_array;
+} snek_object_data_t;
+
+typedef struct SnekObject {
+	int refcount;
+	snek_object_kind_t kind;
+	snek_object_data_t data;
+} snek_object_t;
+
+snek_object_t *new_snek_integer(int value);
+snek_object_t *new_snek_float(float value);
+snek_object_t *new_snek_string(char *value);
+snek_object_t *new_snek_vector3(
+	snek_object_t *x, snek_object_t *y, snek_object_t *z
+);
+snek_object_t *new_snek_array(size_t size);
+
+void refcount_inc(snek_object_t *obj);
+void refcount_dec(snek_object_t *obj);
+void refcount_free(snek_object_t *obj);
+
+bool snek_array_set(snek_object_t *array, size_t index, snek_object_t *value);
+snek_object_t *snek_array_get(snek_object_t *snek_obj, size_t index);
@@ -0,0 +1,31 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "bootlib.h"
+#include "munit.h"
+#include "vm.h"
+
+munit_case(RUN, test_vm_new, {
+	vm_t *vm = vm_new();
+	assert_int(vm->frames->capacity, ==, 8, "frames should have capacity 8");
+	assert_int(vm->objects->capacity, ==, 8, "objects should have capacity 8");
+	vm_free(vm);
+});
+
+munit_case(SUBMIT, test_vm_new_free, {
+	vm_t *vm = vm_new();
+	vm_free(vm);
+	assert(boot_all_freed());
+});
+
+int main() {
+	MunitTest tests[] = {
+		munit_test("/vm", test_vm_new),
+		munit_test("/vm", test_vm_new_free),
+		munit_null_test,
+	};
+
+	MunitSuite suite = munit_suite("mark-and-sweep", tests);
+
+	return munit_suite_main(&suite, NULL, 0, NULL);
+}
@@ -0,0 +1,38 @@
+#include <stdbool.h>
+#include <stddef.h>
+
+#include "stack.h"
+
+typedef struct SnekObject snek_object_t;
+
+typedef struct {
+	size_t size;
+	snek_object_t **elements;
+} snek_array_t;
+
+typedef struct {
+	snek_object_t *x;
+	snek_object_t *y;
+	snek_object_t *z;
+} snek_vector_t;
+
+typedef enum SnekObjectKind {
+	INTEGER,
+	FLOAT,
+	STRING,
+	VECTOR3,
+	ARRAY,
+} snek_object_kind_t;
+
+typedef union SnekObjectData {
+	int v_int;
+	float v_float;
+	char *v_string;
+	snek_vector_t v_vector3;
+	snek_array_t v_array;
+} snek_object_data_t;
+
+typedef struct SnekObject {
+	snek_object_kind_t kind;
+	snek_object_data_t data;
+} snek_object_t;
@@ -0,0 +1,78 @@
+#include <stdio.h>
+
+#include "bootlib.h"
+#include "stack.h"
+
+void stack_push(my_stack_t *stack, void *obj) {
+	if (stack->count == stack->capacity) {
+		// Double stack capacity to avoid reallocing often
+		stack->capacity *= 2;
+		stack->data = boot_realloc(stack->data, stack->capacity * sizeof(void *));
+		if (stack->data == NULL) {
+			// Unable to realloc, just exit :) get gud
+			exit(1);
+		}
+	}
+
+	stack->data[stack->count] = obj;
+	stack->count++;
+
+	return;
+}
+
+void *stack_pop(my_stack_t *stack) {
+	if (stack->count == 0) {
+		return NULL;
+	}
+
+	stack->count--;
+	return stack->data[stack->count];
+}
+
+void stack_free(my_stack_t *stack) {
+	if (stack == NULL) {
+		return;
+	}
+
+	if (stack->data != NULL) {
+		boot_free(stack->data);
+	}
+
+	boot_free(stack);
+}
+
+void stack_remove_nulls(my_stack_t *stack) {
+	size_t new_count = 0;
+
+	// Iterate through the stack and compact non-NULL pointers.
+	for (size_t i = 0; i < stack->count; ++i) {
+		if (stack->data[i] != NULL) {
+			stack->data[new_count++] = stack->data[i];
+		}
+	}
+
+	// Update the count to reflect the new number of elements.
+	stack->count = new_count;
+
+	// Optionally, you might want to zero out the remaining slots.
+	for (size_t i = new_count; i < stack->capacity; ++i) {
+		stack->data[i] = NULL;
+	}
+}
+
+my_stack_t *stack_new(size_t capacity) {
+	my_stack_t *stack = boot_malloc(sizeof(my_stack_t));
+	if (stack == NULL) {
+		return NULL;
+	}
+
+	stack->count = 0;
+	stack->capacity = capacity;
+	stack->data = boot_malloc(stack->capacity * sizeof(void *));
+	if (stack->data == NULL) {
+		boot_free(stack);
+		return NULL;
+	}
+
+	return stack;
+}
--- a/Show More
+++ b/Show More