toys/sww/source/dynamic_buffer.h

#pragma once

#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#if defined(__cplusplus)
extern "C" {
#endif

#if !defined(DEFAULT_CACHE_SIZE)
#define DEFAULT_CACHE_SIZE (4 * 1024)
#endif /* DEFAULT_CACHE_SIZE */

/* NOTE(anjingyu): Non-thread-safe */
typedef struct DynamicBuffer {
  void *buffer;
  size_t size;
  size_t capacity;
} DynamicBuffer;

typedef struct DynamicBuffer AutoReleasePool;

#define DynamicBuffer_Capacity(o) ((DynamicBuffer *)(o))->capacity
#define DynamicBuffer_Size(o) ((DynamicBuffer *)(o))->size
#define DynamicBuffer_AppendChar(o, c) DynamicBuffer_Append(o, &c, sizeof(c))
#define DynamicBuffer_AppendNull(o) DynamicBuffer_Append(o, "\0", 1)
#define DynamicBuffer_AppendWNull(o)                                           \
  do {                                                                         \
    DynamicBuffer_Append(o, "\0", 1);                                          \
    DynamicBuffer_Append(o, "\0", 1);                                          \
  } while (0)
#define DynamicBuffer_AppendNullWithoutSize(o)                                 \
  do {                                                                         \
    DynamicBuffer_Append(o, "\0", 1);                                          \
    DynamicBuffer_Resize(o, DynamicBuffer_Size(o) - 1);                        \
  } while (0)
#define DynamicBuffer_AppendWNullWithoutSize(o)                                \
  do {                                                                         \
    DynamicBuffer_Append(o, "\0", 1);                                          \
    DynamicBuffer_Append(o, "\0", 1);                                          \
    DynamicBuffer_Resize(o, DynamicBuffer_Size(o) - 2);                        \
  } while (0)
#define DynamicBuffer_Buffer(o) (uint8_t *)(((DynamicBuffer *)(o))->buffer)
#define DynamicBuffer_BufferAt(o, idx)                                         \
  ((uint8_t *)(((DynamicBuffer *)(o))->buffer) + idx)
#define DynamicBuffer_BufferEnd(o)                                             \
  ((uint8_t *)(((DynamicBuffer *)(o))->buffer) + ((DynamicBuffer *)(o))->size)
#define DynamicBuffer_Begin(o) (uint8_t *)(((DynamicBuffer *)(o))->buffer)
#define DynamicBuffer_Back(o)                                                  \
  ((((DynamicBuffer *)(o))->size > 0)                                          \
       ? ((uint8_t *)(((DynamicBuffer *)(o))->buffer) +                        \
          ((DynamicBuffer *)(o))->size - 1)                                    \
       : NULL)
#define DynamicBuffer_Clear(o) ((DynamicBuffer *)(o))->size = 0
#define DynamicBuffer_AvailableBuffer(o)                                       \
  (((uint8_t *)((DynamicBuffer *)(o))->buffer) + ((DynamicBuffer *)(o))->size)
#define DynamicBuffer_AvailableCapacity(o)                                     \
  (((DynamicBuffer *)(o))->capacity - ((DynamicBuffer *)(o))->size)
#define DynamicBuffer_AppendString(o, msg)                                     \
  DynamicBuffer_Append((DynamicBuffer *)(o), (const char *)(msg),              \
                       strlen((const char *)(msg)));

#define DynamicBuffer_Swap(o, buffer, size)                                    \
  do {                                                                         \
    free(((DynamicBuffer *)(o))->buffer);                                      \
    ((DynamicBuffer *)(o))->buffer = buffer;                                   \
    ((DynamicBuffer *)(o))->size = ((DynamicBuffer *)(o))->capacity = size;    \
  } while (0)

#define DynamicBuffer_ConstructWithSize(o, size)                               \
  do {                                                                         \
    memset(o, 0, sizeof(DynamicBuffer));                                       \
    DynamicBuffer_Reserve(o, size);                                            \
  } while (0)

#define DynamicBuffer_Construct(o)                                             \
  DynamicBuffer_ConstructWithSize(o, DEFAULT_CACHE_SIZE)

#define DynamicBuffer_Destruct(o)                                              \
  do {                                                                         \
    free(((DynamicBuffer *)(o))->buffer);                                      \
    memset(o, 0, sizeof(DynamicBuffer));                                       \
  } while (0)

int DynamicBuffer_Reserve(DynamicBuffer *o, size_t new_capacity);
int DynamicBuffer_ResetBuffer(DynamicBuffer *o, size_t position);
int DynamicBuffer_Resize(DynamicBuffer *o, size_t new_size);
void DynamicBuffer_Append(DynamicBuffer *o, const void *buffer, size_t size);

#define AutoReleasePool_Construct(o, s)                                        \
  DynamicBuffer_ConstructWithSize((o), (s))
#define AutoReleasePool_Destruct(o) DynamicBuffer_Destruct((o))
void *AutoReleasePool_Alloc(AutoReleasePool *o, size_t size);

#if defined(__cplusplus)
}
#endif