Merge pull request 'implementation_ArrayListSlice' (#1) from implementation_ArrayListSlice into main

Reviewed-on: #1

include/arraylist.h

@@ -7,15 +7,7 @@
 
 typedef struct ArrayList ArrayList;
 
-// FUCK, i forgot one of the main reasons i wanted to
+typedef struct ArraySlice ArraySlice;
-// implement arrays myself was because i needed 
-// array slices or something like this and i completely
-// forgot, fuck, guess i will implement it once i get
-// the tests done.
-typedef struct {
-    ArrayList *array;
-    size_t offset;
-} ArrayListSlice;
 
 typedef enum {
     ARRLIST_OK = 0,
@@ -26,11 +18,14 @@ typedef enum {
     ARRLIST_NULL_ARG,
     ARRLIST_INVALID_ELEM_SIZE,
     ARRLIST_INVALID_CAPACITY,
+    ARRLIST_IS_BORROWED,
+    ARRLIST_INVALID_SLICE,
 } ArrayListErr;
 
 ArrayList *arraylist_init(size_t capacity, size_t elem_size);
 ArrayListErr arraylist_destroy(ArrayList **arr);
 ArrayListErr arraylist_clear(ArrayList *arr);
+ArrayList *arraylist_clone(const ArrayList *arr);
 
 size_t arraylist_size(const ArrayList *arr);
 size_t arraylist_capacity(const ArrayList *arr);
@@ -51,4 +46,22 @@ ArrayListErr arraylist_set(ArrayList *arr, size_t index, void *data);
 ArrayListErr arraylist_resize(ArrayList *arr, size_t new_capacity);
 ArrayListErr arraylist_reserve(ArrayList *arr, size_t size_to_reserve);
 
+//Slice stuff
+ArraySlice *arraylist_slice(ArrayList *arr, size_t start, size_t len);
+ArraySlice *arraylist_slice_unsafe(ArrayList *arr, size_t start, size_t len);
+ArrayListErr arrayslice_destroy(ArraySlice **slice);
+
+bool arrayslice_is_valid(const ArraySlice *slice);
+size_t arrayslice_size(const ArraySlice *slice);
+
+// peek and next can be null, get can't, like, why would you use get without
+// actually getting something?, for validating an index?, use size idiot
+ArrayListErr arrayslice_peek(const ArraySlice *slice, void *out);
+ArrayListErr arrayslice_next(ArraySlice *slice, void *out);
+
+ArrayListErr arrayslice_reset(ArraySlice *slice);
+ArrayListErr arrayslice_advance(ArraySlice *slice, size_t n);
+
+ArrayList *arrayslice_to_arraylist(const ArraySlice *slice);
+
 #endif

src/arraylist.c

@@ -9,6 +9,15 @@ struct ArrayList{
     size_t capacity;
     size_t len;
     size_t elem_size;
+    size_t borrows;
+};
+
+struct ArraySlice {
+    ArrayList *arr;
+    size_t start;
+    size_t end;
+    size_t current;
+    bool is_safe;
 };
 
 // Grow and shrink factor is 2, 1.5 might give different results i guess
@@ -37,6 +46,7 @@ ArrayList *arraylist_init(size_t capacity, size_t elem_size) {
     arr->capacity = capacity;
     arr->elem_size = elem_size;
     arr->len = 0;
+    arr->borrows = 0;
     arr->buffer = malloc(capacity * elem_size);
     if (arr->buffer == NULL) {
         free(arr);
@@ -51,6 +61,10 @@ ArrayListErr arraylist_destroy(ArrayList **arr) {
         return ARRLIST_NULL_ARG;
     }
 
+    if ((*arr)->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     // No problem on using free on NULL :)
     free((*arr)->buffer);
     free(*arr);
@@ -64,6 +78,10 @@ ArrayListErr arraylist_clear(ArrayList *arr) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     arr->len = 0;
     return ARRLIST_OK;
 }
@@ -131,6 +149,10 @@ ArrayListErr arraylist_push_back(ArrayList *arr, void *data) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (arr->len >= arr->capacity) {
         ArrayListErr err = arraylist_grow(arr);
 
@@ -149,6 +171,10 @@ ArrayListErr arraylist_push_front(ArrayList *arr, void *data) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (arr->len >= arr->capacity) {
         ArrayListErr err = arraylist_grow(arr);
 
@@ -179,6 +205,10 @@ ArrayListErr arraylist_insert(ArrayList *arr, size_t index, void *data) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (index > arr->len) {
         return ARRLIST_OUT_OF_BOUNDS;
     }
@@ -209,6 +239,10 @@ ArrayListErr arraylist_pop_back(ArrayList *arr, void *out) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (arr->len < 1) {
         return ARRLIST_EMPTY;
     }
@@ -237,6 +271,10 @@ ArrayListErr arraylist_pop_front(ArrayList *arr, void *out) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (arr->len < 1) {
         return ARRLIST_EMPTY;
     }
@@ -271,6 +309,10 @@ ArrayListErr arraylist_remove_at(ArrayList *arr, size_t index, void *out) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (index >= arr->len) {
         return ARRLIST_OUT_OF_BOUNDS;
     }
@@ -336,6 +378,10 @@ ArrayListErr arraylist_resize(ArrayList *arr, size_t new_capacity) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (new_capacity < 1) {
         return ARRLIST_INVALID_CAPACITY;
     }
@@ -359,6 +405,10 @@ ArrayListErr arraylist_reserve(ArrayList *arr, size_t size_to_reserve) {
         return ARRLIST_NULL_ARG;
     }
 
+    if (arr->borrows > 0) {
+        return ARRLIST_IS_BORROWED;
+    }
+
     if (arr->capacity + size_to_reserve > SIZE_MAX / arr->elem_size ||
         size_to_reserve > SIZE_MAX / arr->elem_size) {
 
@@ -377,3 +427,180 @@ ArrayListErr arraylist_reserve(ArrayList *arr, size_t size_to_reserve) {
     arr->capacity += size_to_reserve;
     return ARRLIST_OK;
 }
+
+ArraySlice *arraylist_slice(ArrayList *arr, size_t start, size_t len) {
+    if (arr == NULL) {
+        return NULL;
+    }
+
+    if (arr->len == 0 || len == 0) {
+        return NULL;
+    }
+
+    if (start > SIZE_MAX / arr->elem_size || len > SIZE_MAX / arr->elem_size) {
+        return NULL;
+    }
+
+    if (start + len > arr->len) {
+        return NULL;
+    }
+
+    ArraySlice *slice = malloc(sizeof(ArraySlice));
+    if (slice == NULL) {
+        return NULL;
+    }
+
+    slice->arr = arr;
+    slice->start = start;
+    slice->end = start + len;
+    slice->current = start;
+    slice->is_safe = true;
+
+    arr->borrows++;
+
+    return slice;
+}
+
+ArraySlice *arraylist_slice_unsafe(ArrayList *arr, size_t start, size_t len) {
+    if (arr == NULL) {
+        return NULL;
+    }
+
+    if (arr->len == 0 || len == 0) {
+        return NULL;
+    }
+
+    if (start > SIZE_MAX / arr->elem_size || len > SIZE_MAX / arr->elem_size) {
+        return NULL;
+    }
+
+    if (start + len > arr->len) {
+        return NULL;
+    }
+
+    ArraySlice *slice = malloc(sizeof(ArraySlice));
+    if (slice == NULL) {
+        return NULL;
+    }
+
+    slice->arr = arr;
+    slice->start = start;
+    slice->end = start + len;
+    slice->current = start;
+    slice->is_safe = false;
+
+    return slice;
+}
+
+ArrayListErr arrayslice_destroy(ArraySlice **slice) {
+    if (slice == NULL || *slice == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    if ((*slice)->is_safe) {
+        (*slice)->arr->borrows--;
+    }
+
+    free(*slice);
+    *slice = NULL;
+
+    return ARRLIST_OK;
+}
+
+bool arrayslice_is_valid(const ArraySlice *slice) {
+    if (slice == NULL) {
+        return false;
+    }
+
+    return slice->current != slice->end;
+}
+
+size_t arrayslice_size(const ArraySlice *slice) {
+    if (slice == NULL) {
+        return 0;
+    }
+
+    return slice->end - slice->start;
+}
+
+ArrayListErr arrayslice_peek(const ArraySlice *slice, void *out) {
+    if (slice == NULL || out == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    if (slice->current >= slice->end) {
+        return ARRLIST_INVALID_SLICE;
+    }
+
+    arraylist_get(slice->arr, slice->current, out);
+
+    return ARRLIST_OK;
+}
+
+ArrayListErr arrayslice_next(ArraySlice *slice, void *out) {
+    // HERE, it makes sense that you want to advance to the next
+    // without actually getting the value so it's good
+    if (slice == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    if (slice->current == slice->end) {
+        return ARRLIST_INVALID_SLICE;
+    }
+
+    arraylist_get(slice->arr, slice->current, out);
+
+    slice->current++;
+    return ARRLIST_OK;
+}
+
+ArrayListErr arrayslice_reset(ArraySlice *slice) {
+    if (slice == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    slice->current = slice->start;
+
+    return ARRLIST_OK;
+}
+
+ArrayListErr arrayslice_advance(ArraySlice *slice, size_t n) {
+    if (slice == NULL) {
+        return ARRLIST_NULL_ARG;
+    }
+
+    if (n > SIZE_MAX - slice->current || slice->current + n > slice->end) {
+        return ARRLIST_OUT_OF_BOUNDS;
+    }
+    
+    slice->current += n;
+
+    return ARRLIST_OK;
+}
+
+ArrayList *arrayslice_to_arraylist(const ArraySlice *slice) {
+    if (slice == NULL || slice->arr == NULL) {
+        return NULL;
+    }
+
+    if (slice->start >= slice->end) {
+        return NULL;
+    }
+
+    size_t len = slice->end - slice->start;
+
+    ArrayList *new_arr = arraylist_init(arraylist_capacity(slice->arr), slice->arr->elem_size);
+    if (new_arr == NULL) {
+        return NULL;
+    }
+
+    memcpy(
+        new_arr->buffer,
+        slice->arr->buffer + (slice->start * slice->arr->elem_size),
+        slice->arr->elem_size * len
+    );
+
+    new_arr->len = len;
+
+    return new_arr;
+}