Initial commit, yay

src/dynamicbuffer/dynamicbuffer.c

@@ -0,0 +1,217 @@
+/*
+ * This code is part of the strategy game operational-space.
+ * operational-space comes with ABSOLUTELY NO WARRANTY and is licensed under GPL-2.0.
+ *    Copyright (C) 2024  VegOwOtenks, Sleppo04
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+#include "dynamicbuffer.h"
+
+int DynamicBuffer_Create(dynamic_buffer_t *destination, size_t initial_capacity)
+{
+	return DynamicBuffer_CreateWithAllocator(destination, initial_capacity, NULL);
+}
+
+int DynamicBuffer_CreateWithAllocator(dynamic_buffer_t *destination, size_t initial_capacity, allocator_t* allocator)
+{
+    if (destination == NULL) {
+        return EDESTADDRREQ;
+    }
+    // Some malloc() implementations return NULL and other return valid pointers on zero-byte-allocation, I'm not handling this shit
+    if (initial_capacity == 0) {
+        return EINVAL;
+    }
+
+    dynamic_buffer_t local;
+
+    local.allocator = allocator;
+    local.capacity  = initial_capacity;
+    local.used      = 0;
+
+    if (allocator != NULL) {
+        local.array = allocator->allocate(allocator, initial_capacity);
+    } else {
+    	local.array = malloc(initial_capacity);
+    }
+    if (local.array == NULL) {
+        return ENOMEM;
+    }
+
+    destination[0] = local;
+
+    return EXIT_SUCCESS;
+}
+
+int DynamicBuffer_EnsureUnusedCapacity(dynamic_buffer_t* buffer, size_t needed_unused)
+{
+    if (buffer == NULL) {
+        return EINVAL;
+    }
+
+    size_t unused_space = buffer->capacity - buffer->used;
+
+    if (needed_unused < unused_space) {
+        return EXIT_SUCCESS;
+    }
+
+    size_t needed_capacity = buffer->capacity + needed_unused;
+    int resize_code = DynamicBuffer_Resize(buffer, needed_capacity);
+
+    if (resize_code) {
+        // ENOMEM
+        return resize_code;
+    }
+
+    return EXIT_SUCCESS;
+}
+
+int DynamicBuffer_EnsureCapacity(dynamic_buffer_t* buffer, size_t minimal_capacity)
+{
+    if (buffer == NULL) {
+        return EINVAL;
+    }
+
+    if (minimal_capacity < buffer->capacity) {
+        return EXIT_SUCCESS;
+    }
+
+    int resize_code = DynamicBuffer_Resize(buffer, minimal_capacity);
+    if (resize_code) {
+        // ENOMEM
+        return resize_code;
+    }
+
+    return EXIT_SUCCESS;
+}
+
+int DynamicBuffer_Resize(dynamic_buffer_t* buffer, size_t new_capacity)
+{
+    if (buffer == NULL) {
+        return EINVAL;
+    }
+    if (new_capacity == 0) {
+        return EINVAL;
+    }
+
+    char* new_array;
+    if (buffer->allocator != NULL) {
+    	new_array = buffer->allocator->reallocate(buffer->allocator, buffer->array, buffer->capacity, new_capacity);
+    } else {
+    	new_array = realloc(buffer->array, new_capacity);
+    }
+    if (new_array == NULL) {
+        return ENOMEM;
+    }
+
+    buffer->array = new_array;
+    buffer->capacity = new_capacity;
+
+    return EXIT_SUCCESS;
+}
+
+int DynamicBuffer_Prune(dynamic_buffer_t* buffer)
+{
+	if (buffer == NULL) {
+		return ENOMEM;
+	}
+
+	return DynamicBuffer_Resize(buffer, buffer->used);
+}
+
+int DynamicBuffer_Reset(dynamic_buffer_t* buffer)
+{
+    if (buffer == NULL) {
+        return EINVAL;
+    }
+
+    buffer->used = 0;
+
+    return EXIT_SUCCESS;
+}
+
+int DynamicBuffer_RewindBytes(dynamic_buffer_t* buffer, size_t bytes)
+{
+	if (buffer == NULL) {
+		return EINVAL;
+	}
+	if (buffer->used < bytes) {
+		return EBOUNDS;
+	}
+
+	buffer->used -= bytes;
+
+	return EXIT_SUCCESS;
+}
+
+int DynamicBuffer_Store(dynamic_buffer_t* buffer, const void* data, size_t data_size)
+{
+    if (buffer == NULL) {
+        return EINVAL;
+    }
+    if (data == NULL) {
+        return EINVAL;
+    }
+    if (data_size == 0) {
+        return EXIT_SUCCESS;
+    }
+
+    int ensure_code = DynamicBuffer_EnsureUnusedCapacity(buffer, data_size);
+    if (ensure_code) {
+        // ENOMEM
+        return ensure_code;
+    }
+
+    void* destination = ((char*) buffer->array) + buffer->used;
+    memcpy(destination, data, data_size);
+    buffer->used += data_size;
+
+    return EXIT_SUCCESS;
+}
+
+size_t DynamicBuffer_GetBlockCount(dynamic_buffer_t* buffer, size_t block_size)
+{
+	return buffer->used / block_size;
+}
+
+void* DynamicBuffer_ReadAt(dynamic_buffer_t* buffer, size_t offset)
+{
+	if (offset >= buffer->used) {
+		return NULL;
+	}
+
+	return (void*) (((char*) buffer->array) + offset);
+}
+
+void* DynamicBuffer_ReadBlockAt(dynamic_buffer_t* buffer, size_t block_size, size_t index)
+{
+	return DynamicBuffer_ReadAt(buffer, block_size * index);
+}
+
+int DynamicBuffer_Destroy(dynamic_buffer_t* buffer)
+{
+    if (buffer == NULL) {
+        return EINVAL;
+    }
+    if (buffer->allocator == NULL) {
+    	free(buffer->array);
+    } else {
+    	buffer->allocator->free(buffer->allocator, buffer->array, buffer->capacity);
+    }
+    buffer->array = NULL;
+    buffer->capacity = 0;
+    buffer->used = 0;
+
+    return EXIT_SUCCESS;
+}