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Add test suite, fix about five IPS bugs found

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Alcaro
2016-12-23 13:13:21 +01:00
parent 81a35ee437
commit 3f3bf6c3a5
10 changed files with 381 additions and 27 deletions
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51
patch/ips.cpp
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@@ -181,8 +181,8 @@ result apply(const file& patch, const file& source, file& target)
static result create(struct mem sourcemem, struct mem targetmem, struct mem * patchmem)
{
unsigned int sourcelen=sourcemem.len;
unsigned int targetlen=targetmem.len;
int sourcelen=sourcemem.len;
int targetlen=targetmem.len;
const unsigned char * source=sourcemem.ptr;
const unsigned char * target=targetmem.ptr;
@@ -191,10 +191,10 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
if (targetlen>=16777216) return e_too_big;
unsigned int offset=0;
unsigned int outbuflen=4096;
int offset=0;
int outbuflen=4096;
unsigned char * out=(uint8_t*)malloc(outbuflen);
unsigned int outlen=0;
int outlen=0;
#define write8(val) do { out[outlen++]=(val); if (outlen==outbuflen) { outbuflen*=2; out=(uint8_t*)realloc(out, outbuflen); } } while(0)
#define write16(val) do { write8((val)>>8); write8((val)); } while(0)
#define write24(val) do { write8((val)>>16); write8((val)>>8); write8((val)); } while(0)
@@ -204,10 +204,11 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
write8('C');
write8('H');
int lastknownchange=0;
int lastwritten=0;
//int forcewrite=(targetlen>sourcelen?1:0);
while (offset<targetlen)
{
while (offset<sourcelen && (offset<sourcelen?source[offset]:0)==target[offset]) offset++;
while (offset<targetlen && (offset<sourcelen?source[offset]:0)==target[offset]) offset++;
//check how much we need to edit until it starts getting similar
int thislen=0;
int consecutiveunchanged=0;
@@ -215,14 +216,14 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
if (thislen<0) thislen=0;
while (true)
{
unsigned int thisbyte=offset+thislen+consecutiveunchanged;
if (thisbyte<sourcelen && (thisbyte<sourcelen?source[thisbyte]:0)==target[thisbyte]) consecutiveunchanged++;
int thisbyte=offset+thislen+consecutiveunchanged;
if (thisbyte<targetlen && (thisbyte<sourcelen?source[thisbyte]:0)==target[thisbyte]) consecutiveunchanged++;
else
{
thislen+=consecutiveunchanged+1;
consecutiveunchanged=0;
}
if (consecutiveunchanged>=6 || thislen>=65536) break;
if (consecutiveunchanged>=6 || thislen>65535) break;
}
//avoid premature EOF
@@ -246,7 +247,7 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
int i=0;
while (true)
{
unsigned int pos=offset+byteshere+i-1;
int pos=offset+byteshere+i-1;
if (pos>=targetlen || target[pos]!=thisbyte || byteshere+i>65535) break;
if (pos>=sourcelen || (pos<sourcelen?source[pos]:0)!=thisbyte)
{
@@ -264,6 +265,7 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
write16(byteshere);
write8(target[offset]);
offset+=byteshere;
lastwritten=offset;
}
else
{
@@ -280,7 +282,8 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
}
if (byteshere>8+5 || //rle-worthy despite two ips headers
(byteshere>8 && stopat+byteshere==thislen) || //rle-worthy at end of data
(byteshere>8 && !memcmp(&target[offset+stopat+byteshere], &target[offset+stopat+byteshere+1], 9-1)))//rle-worthy before another rle-worthy
(byteshere>8 && offset+stopat+byteshere+8 <= thislen &&
!memcmp(&target[offset+stopat+byteshere], &target[offset+stopat+byteshere+1], 9-1)))//rle-worthy before another rle-worthy
{
if (stopat) thislen=stopat;
break;//we don't scan the entire block if we know we'll want to RLE, that'd gain nothing.
@@ -295,6 +298,12 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
}
}
//avoid infinite loops if an RLEable block starts at 'EOF'
if (offset+thislen == 0x454F46)
{
if (thislen==0xFFFF) thislen--;
else thislen++;
}
if (thislen>3 && !memcmp(&target[offset], &target[offset+1], thislen-1))//still worth it?
{
write24(offset);
@@ -306,13 +315,29 @@ static result create(struct mem sourcemem, struct mem targetmem, struct mem * pa
{
write24(offset);
write16(thislen);
int i;
for (i=0;i<thislen;i++)
for (int i=0;i<thislen;i++)
{
write8(target[offset+i]);
}
}
offset+=thislen;
lastwritten=offset;
}
}
if (sourcelen<targetlen && lastwritten!=targetlen)
{
if (targetlen-1==0x454F46)
{
write24(targetlen-2);
write16(2);
write8(target[targetlen-2]);
write8(target[targetlen-1]);
}
else
{
write24(targetlen-1);
write16(1);
write8(target[targetlen-1]);
}
}
write8('E');