refactor: Changed Result types return sytaxis

descripcion mas detallada

CMakeLists.txt

@@ -24,6 +24,12 @@ add_executable(arena_main src/main.c)
 
 target_link_libraries(arena_main arena_lib)
 
+function(enable_sanitizers target)
+    target_compile_options(${target} PRIVATE -fsanitize=address -fno-omit-frame-pointer)
+    target_link_options(${target} PRIVATE -fsanitize=address)
+endfunction()
+
+
 # ------------------------
 # Testing
 # ------------------------

include/arena.h

@@ -50,13 +50,17 @@ ArenaResult arena_init(size_t capacity);
 void arena_destroy(Arena *arena);
 
 ArenaPointer arena_alloc(Arena *arena, size_t size, size_t alignment);
-ArenaErr arena_push(Arena *arena, void *data, size_t size, size_t alignment);
+ArenaPointer arena_push(Arena *arena, void *data, size_t size, size_t alignment);
 ArenaErr arena_realloc(Arena *arena, size_t new_capacity);
 
-SizeResult align_arena_offset(Arena *arena, size_t alignment);
-
+SizeResult get_arena_align_padding(Arena *arena, size_t alignment);
+ArenaErr arena_ensure_capacity(Arena *arena, size_t size, size_t alignment);
 // Should be moved to something like general utilities,
 // i should make one for all my c projects
 bool mul_size_t_safe(size_t a, size_t b, size_t *out);
 
+
+
+
+
 #endif // !ARENA_H

src/arena.c

@@ -6,22 +6,13 @@
 #include <string.h>
 
 ArenaResult arena_init(size_t capacity) {
+    if (capacity < 1) {
+        return (ArenaResult) {.is_valid = false, .err = ARENA_INVALID_SIZE};
+    }
 
     void *buffer = malloc(capacity);
     if (buffer == NULL) {
-        ArenaResult err = {
-            .is_valid = false,
-            .err = ARENA_BAD_ALLOC,
-        };
-        return err;
-    }
-
-    if (capacity < 1) {
-        ArenaResult err = {
-            .is_valid = false,
-            .err = ARENA_INVALID_SIZE,
-        };
-        return err;
+        return (ArenaResult) {.is_valid = false, .err = ARENA_BAD_ALLOC};
     }
 
     Arena new_arena = {
@@ -29,74 +20,64 @@ ArenaResult arena_init(size_t capacity) {
         .capacity = capacity,
         .offset = 0,
     };
-    ArenaResult val = {
-        .is_valid = true,
-        .arena = new_arena,
-    };
 
-    return val;
+    return (ArenaResult) {.is_valid = true, .arena = new_arena};
 }
 
 void arena_destroy(Arena *arena) {
-    if (arena == NULL) {
-        return;
-    }
-
+    free(arena->buffer);
+    arena->buffer = NULL;
     arena->offset = 0;
     arena->capacity = 0;
-    free(arena->buffer);
 }
 
 ArenaPointer arena_alloc(Arena *arena, size_t size, size_t alignment) {
     if (arena == NULL) {
-        ArenaPointer err = {
-            .is_valid = false,
-            .err = ARENA_NULL_ARG,
-        };
-        return err;
+        return (ArenaPointer) {.is_valid = false, .err = ARENA_NULL_ARG};
     }
 
-    SizeResult new_offset = align_arena_offset(arena, alignment);
-    if (!new_offset.is_valid) {
-        ArenaPointer err = {
-            .is_valid = false,
-            .err = new_offset.err,
-        };
-        return err;
+    SizeResult padding = get_arena_align_padding(arena, alignment);
+    if (!padding.is_valid) {
+        return (ArenaPointer) {.is_valid = false, .err = padding.err};
     }
 
-    if (new_offset.val + size >= arena->capacity) {
-        ArenaPointer err = {
-            .is_valid = false,
-            .err = ARENA_OUT_OF_SPACE,
-        };
-        return err;
+
+    if (arena->offset + padding.val >= arena->capacity) {
+        return (ArenaPointer) {.is_valid = false, .err = ARENA_OUT_OF_SPACE};
     }
 
-    arena->offset = new_offset.val;
+    if (arena->offset > SIZE_MAX - padding.val - size) {
+        return (ArenaPointer) {.is_valid = false, .err = ARENA_CAPACITY_OVERFLOW};
+    }
 
-    ArenaPointer val = {
-        .is_valid = true,
-        .address = arena->buffer + arena->offset,
-    };
-    return val;
+    size_t aligned_offset = arena->offset + padding.val;
+
+    arena->offset = aligned_offset + size;
+    return (ArenaPointer) {.is_valid = true, .address = arena->buffer + aligned_offset};
 }
 
-ArenaErr arena_push(Arena *arena, void *data, size_t size, size_t alignment) {
-    if (arena == NULL || data == NULL) {
+ArenaErr arena_ensure_capacity(Arena *arena, size_t size, size_t alignment) {
+    if (arena == NULL) {
         return ARENA_NULL_ARG;
     }
 
-    ArenaPointer pointer = arena_alloc(arena, size, alignment);
-
-    if (!pointer.is_valid) {
-        return pointer.err;
+    SizeResult padding = get_arena_align_padding(arena, alignment);
+    if (!padding.is_valid) {
+        return padding.err;
+    }
+    while (true) {
+        if (arena->offset > SIZE_MAX - padding.val - size) {
+            return ARENA_CAPACITY_OVERFLOW;
         }
-    while (!pointer.is_valid && pointer.err == ARENA_OUT_OF_SPACE) {
-        size_t new_capacity;
 
-        bool is_overflow = mul_size_t_safe(arena->capacity, 2, &new_capacity);
-        if (is_overflow) {
+        size_t required = arena->offset + padding.val + size;
+
+        if (required <= arena->capacity) {
+            return ARENA_OK;
+        }
+
+        size_t new_capacity;
+        if (mul_size_t_safe(arena->capacity, 2, &new_capacity)) {
             return ARENA_CAPACITY_OVERFLOW;
         }
 
@@ -104,8 +85,22 @@ ArenaErr arena_push(Arena *arena, void *data, size_t size, size_t alignment) {
         if (err != ARENA_OK) {
             return err;
         }
+    }
+}
 
-        pointer = arena_alloc(arena, size, alignment);
+ArenaPointer arena_push(Arena *arena, void *data, size_t size, size_t alignment) {
+    if (arena == NULL || data == NULL) {
+        return (ArenaPointer) {.is_valid = false, .err = ARENA_NULL_ARG};
+    }
+
+    ArenaErr err = arena_ensure_capacity(arena, size, alignment);
+    if (err != ARENA_OK) {
+        return (ArenaPointer) {.is_valid = false, .err = err};
+    }
+
+    ArenaPointer pointer = arena_alloc(arena, size, alignment);
+    if (!pointer.is_valid) {
+        return pointer;
     }
     
     memcpy(
@@ -113,7 +108,7 @@ ArenaErr arena_push(Arena *arena, void *data, size_t size, size_t alignment) {
         data,
         size);
 
-    return ARENA_OK;
+    return pointer;
 }
 
 ArenaErr arena_realloc(Arena *arena, size_t new_capacity) {
@@ -131,30 +126,19 @@ ArenaErr arena_realloc(Arena *arena, size_t new_capacity) {
     return ARENA_OK;
 }
 
-SizeResult align_arena_offset(Arena *arena, size_t alignment) {
+SizeResult get_arena_align_padding(Arena *arena, size_t alignment) {
     if (arena == NULL) {
-        SizeResult err = {
-            .is_valid = false,
-            .err = ARENA_NULL_ARG,
-        };
-        return err;
+        return (SizeResult) {.is_valid = false, .err = ARENA_NULL_ARG};
     }
 
     if (alignment < 1) {
-        SizeResult err = {
-            .is_valid = false,
-            .err = ARENA_INVALID_ALIGN,
-        };
-        return err;
+        return (SizeResult) {.is_valid = false, .err = ARENA_INVALID_ALIGN};
     }
 
-    SizeResult val = {
-        .is_valid = true,
-        .val = ((arena->offset + (alignment - 1)) & ~(alignment - 1)),
-        // Formula for alignment, found at stackoverflow, i came up with one
-        // but it involved 3 divisions, this one is way faster :)
-    };
-    return val;
+    uintptr_t current_address = (uintptr_t) (arena->buffer + arena->offset);
+    uintptr_t aligned = ((current_address + (alignment - 1)) & ~(alignment - 1));
+
+    return (SizeResult) {.is_valid = true, .err = aligned - current_address};
 }
 
 bool mul_size_t_safe(size_t a, size_t b, size_t *out) {

test/CMakeLists.txt

@@ -7,4 +7,9 @@ target_link_libraries(test_arena
     cmocka::cmocka
 )
 
+enable_sanitizers(test_arena)
+
+target_compile_options(test_arena PRIVATE -fsanitize=address -fno-omit-frame-pointer)
+target_link_options(test_arena PRIVATE -fsanitize=address)
+
 add_test(NAME arena_tests COMMAND test_arena)

test/test_arena.c

@@ -1,6 +1,82 @@
-#include "arena.h"
+#include <stdalign.h>
 #include <stdlib.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <setjmp.h>
+#include <cmocka.h>
+#include <string.h>
+
+#include "arena.h"
+
+static void test_push_3_ints(void **state) {
+    (void) state;
+
+    ArenaResult value = arena_init(sizeof(int) * 3);
+    assert_true(value.is_valid);
+    Arena arena = value.arena;
+
+    int int_to_push = 20;
+    ArenaPointer result = arena_push(&arena, &int_to_push, sizeof(int), alignof(int));
+    assert_true(result.is_valid);
+    assert_int_equal(20, *(int*)result.address);
+
+    int_to_push = 30;
+    result = arena_push(&arena, &int_to_push, sizeof(int), alignof(int));
+    assert_true(result.is_valid);
+    assert_int_equal(30, *(int*) result.address);
+
+    int_to_push = 40;
+    result = arena_push(&arena, &int_to_push, sizeof(int), alignof(int));
+    assert_true(result.is_valid);
+    assert_int_equal(40, *(int*) result.address);
+
+    arena_destroy(&arena);
+}
+
+static void test_push_3_ints_2_doubles(void **state) {
+    (void) state;
+
+    ArenaResult value = arena_init((sizeof(int) * 3) + (sizeof(double) * 2));
+    assert_true(value.is_valid);
+    Arena arena = value.arena;
+
+    int int_to_push = 20;
+    ArenaPointer result = arena_push(&arena, &int_to_push, sizeof(int), alignof(int));
+    assert_true(result.is_valid);
+    assert_int_equal(20, *(int*)result.address);
+
+    double double_to_push = 4.57;
+    result = arena_push(&arena, &double_to_push, sizeof(double), alignof(double));
+    assert_true(result.is_valid);
+    assert_double_equal(4.57, *(double*)result.address, 1e-6);
+
+    int_to_push = 30;
+    result = arena_push(&arena, &int_to_push, sizeof(int), alignof(int));
+    assert_true(result.is_valid);
+    assert_int_equal(30, *(int*)result.address);
+
+    int_to_push = 40;
+    result = arena_push(&arena, &int_to_push, sizeof(int), alignof(int));
+    assert_true(result.is_valid);
+    assert_int_equal(40, *(int*) result.address);
+
+    double_to_push = 267.33;
+    result = arena_push(&arena, &double_to_push, sizeof(double), alignof(double));
+    assert_true(result.is_valid);
+    assert_double_equal(267.33, *(double*) result.address, 1e-6);
+
+    arena_destroy(&arena);
+}
+
 
 int main(void) {
-    return EXIT_SUCCESS;
+    const struct CMUnitTest tests[] = {
+        cmocka_unit_test(test_push_3_ints),
+        cmocka_unit_test(test_push_3_ints_2_doubles),
+    };
+
+
+    return cmocka_run_group_tests(tests, NULL, NULL);
 }