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static inline Eina_Intbuf *eina_intbuf_new(void)
{
Eina_Intbuf *buf;
buf = calloc(1, sizeof (Eina_Intbuf));
return buf;
}
static void eina_intbuf_free(Eina_Intbuf *buf)
{
free(buf->bytes);
free(buf);
}
static inline void eina_intbuf_push(Eina_Intbuf *buf, int data)
{
int delta = data - buf->last_data;
unsigned char *tmp;
unsigned char data[5];
unsigned char idx = 4;
Eina_Bool neg = EINA_FALSE;
/* detect negative value */
if (delta < 0)
{
delta *= -1;
neg = EINA_TRUE;
}
/* Special case for storing negative value and no continuation bit */
data[idx] = (delta & 0x3F) | (neg ? 0x40 : 0x0);
/* Update index and delta after storing data */
delta = delta >> 6;
idx--;
while (delta)
{
/* Normal case where we store the data with the continuing bit */
data[idx] = (delta & 0x7F) | 0x80;
/* Update index and delta after storing data */
delta = delta >> 7;
idx--;
}
/* resize bytes buffer and store data at the end of the buffer */
tmp = realloc(buf->bytes, buf->length + 5 - idx);
if (!tmp) return ;
buf->bytes = tmp;
memcpy(tmp, data + idx + 1, 5 - idx);
/* update last data to the last pushed data */
buf->last_data = data;
}
static inline inline Eina_Bool eina_intbuf_read(Eina_Intbuf *buf,
unsigned int *buffer_offset,
int *data)
{
int delta = 0;
/* end of the buffer ! */
if (*buffer_offset >= buf->length)
return EINA_FALSE;
/* as long as we find the continuation bit */
while (buf->bytes[*buffer_offset] & 0x80)
{
/* we can add those bit to the current delta value */
delta = (delta << 7) + (buf->bytes[*buffer_offset] & 0x7F);
(*buffer_offset)++;
}
/* handling the specific case of negative value and end of integer stream */
delta = (delta << 7) + (buf->bytes[*buffer_offset] & 0x3F);
if (buf->bytes[*buffer_offset] & 0x40)
delta *= -1;
/* update data by delta value */
*data += delta;
return EINA_TRUE;
}
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