Files
TencentOS-tiny/components/ota/common/lzma/3rdparty/Bra86.c
daishengdong 5b51d50ade add ota algorithm for device
1. effective "Differential Upgrade" patch algorithm with high compression rate
2. effective recovery algorithm support recovery firmware in blocks which has low memory consumption and wear-leveling strategies, especially suitable for embeded devices with low RAM.
3. add sample ota bootloader project, see:
board\TencentOS_tiny_EVB_MX_Plus\KEIL\ota\ota_bootloader_recovery
4. add sample application project for download firmware through http, see:
board\TencentOS_tiny_EVB_MX_Plus\KEIL\ota\ota_application_download_through_http
5. add sample application project for download firmware through qcloud explorer console, see:
board\TencentOS_tiny_EVB_MX_Plus\KEIL\ota\ota_application_download_through_qcloud_iot_explorer
6. an OTA markdown document is pending
2020-06-02 15:03:42 +08:00

83 lines
1.7 KiB
C

/* Bra86.c -- Converter for x86 code (BCJ)
2017-04-03 : Igor Pavlov : Public domain */
#include "Precomp.h"
#include "Bra.h"
#define Test86MSByte(b) ((((b) + 1) & 0xFE) == 0)
SizeT x86_Convert(Byte *data, SizeT size, UInt32 ip, UInt32 *state, int encoding)
{
SizeT pos = 0;
UInt32 mask = *state & 7;
if (size < 5)
return 0;
size -= 4;
ip += 5;
for (;;)
{
Byte *p = data + pos;
const Byte *limit = data + size;
for (; p < limit; p++)
if ((*p & 0xFE) == 0xE8)
break;
{
SizeT d = (SizeT)(p - data - pos);
pos = (SizeT)(p - data);
if (p >= limit)
{
*state = (d > 2 ? 0 : mask >> (unsigned)d);
return pos;
}
if (d > 2)
mask = 0;
else
{
mask >>= (unsigned)d;
if (mask != 0 && (mask > 4 || mask == 3 || Test86MSByte(p[(size_t)(mask >> 1) + 1])))
{
mask = (mask >> 1) | 4;
pos++;
continue;
}
}
}
if (Test86MSByte(p[4]))
{
UInt32 v = ((UInt32)p[4] << 24) | ((UInt32)p[3] << 16) | ((UInt32)p[2] << 8) | ((UInt32)p[1]);
UInt32 cur = ip + (UInt32)pos;
pos += 5;
if (encoding)
v += cur;
else
v -= cur;
if (mask != 0)
{
unsigned sh = (mask & 6) << 2;
if (Test86MSByte((Byte)(v >> sh)))
{
v ^= (((UInt32)0x100 << sh) - 1);
if (encoding)
v += cur;
else
v -= cur;
}
mask = 0;
}
p[1] = (Byte)v;
p[2] = (Byte)(v >> 8);
p[3] = (Byte)(v >> 16);
p[4] = (Byte)(0 - ((v >> 24) & 1));
}
else
{
mask = (mask >> 1) | 4;
pos++;
}
}
}