Data.c

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/*
 * Objectively: Ultra-lightweight object oriented framework for GNU C.
 * Copyright (C) 2014 Jay Dolan <jay@jaydolan.com>
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source distribution.
 */
 
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
#include "Data.h"
#include "Hash.h"
 
#define _Class _Data
 
#define DATA_BLOCK_SIZE 4096
 
#pragma mark - Object
 
static Object *copy(const Object *self) {
 
  const Data *this = (const Data *) self;
 
  Data *that = $(alloc(Data), initWithCapacity, this->capacity ?: this->length);
  $(that, appendBytes, this->bytes, this->length);
 
  return (Object *) that;
}
 
static void dealloc(Object *self) {
 
  Data *this = (Data *) self;
 
  if (this->destroy) {
    if (this->bytes) {
      this->destroy(this->bytes);
    }
  }
 
  super(Object, self, dealloc);
}
 
static int hash(const Object *self) {
 
  Data *this = (Data *) self;
 
  int hash = HASH_SEED;
  hash = HashForInteger(hash, this->length);
 
  const Range range = { 0, this->length };
  hash = HashForBytes(hash, this->bytes, range);
 
  return hash;
}
 
static bool isEqual(const Object *self, const Object *other) {
 
  if (super(Object, self, isEqual, other)) {
    return true;
  }
 
  if (other && $(other, isKindOfClass, _Data())) {
 
    const Data *this = (Data *) self;
    const Data *that = (Data *) other;
 
    if (this->length == that->length) {
      if (this->length == 0) {
        return true;
      }
 
      return memcmp(this->bytes, that->bytes, this->length) == 0;
    }
  }
 
  return false;
}
 
#pragma mark - Data
 
static Data *dataWithBytes(const uint8_t *bytes, size_t length) {
 
  return $(alloc(Data), initWithBytes, bytes, length);
}
 
static Data *dataWithConstMemory(const ident mem, size_t length) {
 
  return $(alloc(Data), initWithConstMemory, mem, length);
}
 
static Data *dataWithContentsOfFile(const char *path) {
 
  return $(alloc(Data), initWithContentsOfFile, path);
}
 
static Data *dataWithMemory(ident mem, size_t length) {
 
  return $(alloc(Data), initWithMemory, mem, length);
}
 
static Data *initWithBytes(Data *self, const uint8_t *bytes, size_t length) {
 
  ident mem = NULL;
  if (length) {
    mem = malloc(length);
    assert(mem);
 
    memcpy(mem, bytes, length);
  }
 
  return $(self, initWithMemory, mem, length);
}
 
static Data *initWithConstMemory(Data *self, const ident mem, size_t length) {
 
  self = (Data *) super(Object, self, init);
  if (self) {
    self->bytes = mem;
    self->length = length;
    self->capacity = length;
  }
 
  return self;
}
 
static Data *initWithContentsOfFile(Data *self, const char *path) {
 
  assert(path);
 
  FILE *file = fopen(path, "rb");
  if (file) {
    ident mem = NULL;
 
    int err = fseek(file, 0, SEEK_END);
    assert(err == 0);
 
    const size_t length = ftell(file);
    if (length) {
 
      mem = malloc(length);
      assert(mem);
 
      err = fseek(file, 0, SEEK_SET);
      assert(err == 0);
 
      const size_t read = fread(mem, length, 1, file);
      assert(read == 1);
    }
 
    fclose(file);
    return $(self, initWithMemory, mem, length);
  }
 
  return release(self);
}
 
static Data *initWithMemory(Data *self, ident mem, size_t length) {
 
  self = $(self, initWithConstMemory, mem, length);
  if (self) {
    self->destroy = free;
  }
 
  return self;
}
 
static bool writeToFile(const Data *self, const char *path) {
 
  assert(path);
 
  FILE *file = fopen(path, "w");
  if (file) {
 
    size_t count = 1;
 
    if (self->length) {
      count = fwrite(self->bytes, self->length, 1, file);
    }
 
    fclose(file);
 
    if (count == 1) {
      return true;
    }
  }
 
  return false;
}
 
#pragma mark - Data mutation
 
static void appendBytes(Data *self, const uint8_t *bytes, size_t length) {
 
  const size_t oldLength = self->length;
 
  $(self, setLength, self->length + length);
 
  if (length) {
    memcpy(self->bytes + oldLength, bytes, length);
  }
}
 
static void appendData(Data *self, const Data *data) {
 
  $(self, appendBytes, data->bytes, data->length);
}
 
static Data *data(void) {
 
  return $(alloc(Data), init);
}
 
static Data *dataWithCapacity(size_t capacity) {
 
  return $(alloc(Data), initWithCapacity, capacity);
}
 
static Data *init(Data *self) {
 
  return $(self, initWithCapacity, 0);
}
 
static Data *initWithCapacity(Data *self, size_t capacity) {
 
  self = (Data *) super(Object, self, init);
  if (self) {
 
    self->capacity = capacity;
    if (self->capacity) {
 
      self->bytes = calloc(capacity, sizeof(uint8_t));
      assert(self->bytes);
    }
 
    self->destroy = free;
  }
 
  return self;
}
 
static Data *initWithData(Data *self, const Data *data) {
 
  self = $(self, initWithCapacity, data->length);
  if (self) {
    $(self, appendData, data);
  }
 
  return self;
}
 
static void setLength(Data *self, size_t length) {
 
  const size_t newCapacity = (length / _pageSize + 1) * _pageSize;
  if (newCapacity > self->capacity) {
 
    if (self->bytes == NULL) {
      self->bytes = calloc(newCapacity, sizeof(uint8_t));
      assert(self->bytes);
    } else {
      if (self->destroy != free) {
        uint8_t *owned = malloc(newCapacity);
        assert(owned);
        memcpy(owned, self->bytes, self->length);
        if (length > self->length) {
          memset(owned + self->length, 0, length - self->length);
        }
        self->bytes = owned;
        self->destroy = free;
      } else {
        self->bytes = realloc(self->bytes, newCapacity);
        assert(self->bytes);
        if (length > self->length) {
          memset(self->bytes + self->length, 0, length - self->length);
        }
      }
    }
 
    self->capacity = newCapacity;
  } else if (length > self->length) {
    memset(self->bytes + self->length, 0, length - self->length);
  }
 
  self->length = length;
}
 
#pragma mark - Class lifecycle
 
static void initialize(Class *clazz) {
 
  ((ObjectInterface *) clazz->interface)->copy = copy;
  ((ObjectInterface *) clazz->interface)->dealloc = dealloc;
  ((ObjectInterface *) clazz->interface)->hash = hash;
  ((ObjectInterface *) clazz->interface)->isEqual = isEqual;
 
  ((DataInterface *) clazz->interface)->dataWithBytes = dataWithBytes;
  ((DataInterface *) clazz->interface)->dataWithConstMemory = dataWithConstMemory;
  ((DataInterface *) clazz->interface)->dataWithContentsOfFile = dataWithContentsOfFile;
  ((DataInterface *) clazz->interface)->dataWithMemory = dataWithMemory;
  ((DataInterface *) clazz->interface)->initWithBytes = initWithBytes;
  ((DataInterface *) clazz->interface)->initWithConstMemory = initWithConstMemory;
  ((DataInterface *) clazz->interface)->initWithContentsOfFile = initWithContentsOfFile;
  ((DataInterface *) clazz->interface)->initWithMemory = initWithMemory;
  ((DataInterface *) clazz->interface)->appendBytes = appendBytes;
  ((DataInterface *) clazz->interface)->appendData = appendData;
  ((DataInterface *) clazz->interface)->data = data;
  ((DataInterface *) clazz->interface)->dataWithCapacity = dataWithCapacity;
  ((DataInterface *) clazz->interface)->init = init;
  ((DataInterface *) clazz->interface)->initWithCapacity = initWithCapacity;
  ((DataInterface *) clazz->interface)->initWithData = initWithData;
  ((DataInterface *) clazz->interface)->setLength = setLength;
  ((DataInterface *) clazz->interface)->writeToFile = writeToFile;
}
 
Class *_Data(void) {
  static Class *clazz;
  static Once once;
 
  do_once(&once, {
    clazz = _initialize(&(const ClassDef) {
      .name = "Data",
      .superclass = _Object(),
      .instanceSize = sizeof(Data),
      .interfaceOffset = offsetof(Data, interface),
      .interfaceSize = sizeof(DataInterface),
      .initialize = initialize,
    });
  });
 
  return clazz;
}
 
#undef _Class