Flips/patch/patch.h

206 lines
6.6 KiB
C++

#pragma once
#include "../arlib.h"
namespace patch {
enum type {
t_unknown,
t_ips,
t_ups,
t_bps
};
type identify(const file& patch);
enum result {
e_ok,
//You may get an output file along with some of these errors.
e_to_output,//You attempted to apply a patch to its output.
e_not_this, //This is not the intended input file for this patch.
e_damaged, //The patch is technically valid, but seems scrambled or malformed.
e_broken, //This patch is not of the expected format, or it's malformed somehow.
e_io, //The patch could not be read.
e_identical, //The input files are identical.
e_too_big, //The program (or the patch format) can't handle that big files.
e_out_of_mem,//Memory allocation failure.
e_canceled //Patch creation callback said cancel.
};
namespace ips {
result apply(const file& patch, const file& source, file& target);
static inline result apply(const file& patch, const file& source, file&& target) { return apply(patch, source, (file&)target); }
result create(const file& source, const file& target, file& patch);
static inline result create(const file& source, const file& target, file&& patch) { return create(source, target, (file&)patch); }
}
namespace ups {
result apply(const file& patch, const file& source, file& target);
static inline result apply(const file& patch, const file& source, file&& target) { return apply(patch, source, (file&)target); }
//ups is worthless
//result create(const file& source, const file& target, file& patch);
}
namespace bps {
result apply(const file& patch, const file& source, file& target, bool accept_wrong_input = false);
static inline result apply(const file& patch, const file& source, file&& target, bool accept_wrong_input = false)
{
return apply(patch, source, (file&)target, accept_wrong_input);
}
//Because this one can take quite a long time, a progress meter is supplied. total is guaranteed to
// be constant between every call until this function returns, done is guaranteed to increase
// between each call, and done/total is an approximate percentage counter. Anything else is
// undefined; for example, progress may or may not be called for done=0, progress may or may not be
// called for done=total, done may or may not increase by the same amount between each call, and
// the duration between each call may or may not be constant.
//To cancel patch creation, return true from the callback. It's safe to pass in NULL if you're not interested.
result create(const file& source, const file& target, const file& metadata, file& patch,
function<bool(size_t done, size_t total)> progress);
static inline result create(const file& source, const file& target, const file& metadata, file&& patch,
function<bool(size_t done, size_t total)> progress)
{
return create(source, target, metadata, (file&)patch, progress);
}
static inline result create(const file& source, const file& target, file& patch,
function<bool(size_t done, size_t total)> progress)
{
return create(source, target, file::mem(NULL), (file&)patch, progress);
}
static inline result create(const file& source, const file& target, file&& patch,
function<bool(size_t done, size_t total)> progress)
{
return create(source, target, (file&)patch, progress);
}
struct info {
result parse(const file& patch, bool changefrac = false);
size_t size_in;
size_t size_out;
uint32_t crc_in;
uint32_t crc_out;
array<byte> metadata;
//Tells approximately how much of the input ROM is changed compared to the output ROM.
//It's quite heuristic. The algorithm may change with or without notice.
//As of writing, I believe this is accurate to 2 significant digits in base 10.
//It's also more expensive to calculate than the other data, so it's optional.
//If you don't want it, their values are undefined.
//The denominator is always guaranteed nonzero, even if something else says it's undefined.
//Note that this can return success for invalid patches.
size_t change_num;
size_t change_denom;
};
}
//Used for patch application.
class filebufreader {
file& f;
size_t fpos;
array<byte> buf;
size_t bufpos;
uint32_t crc;
public:
filebufreader(file& f) : f(f), fpos(0), bufpos(0), crc(0) {}
arrayview<byte> peek(size_t bytes)
{
if (buf.size()-bufpos < bytes)
{
buf = buf.slice(bufpos, buf.size()-bufpos);
bufpos = 0;
size_t bytehave = buf.size();
size_t byteread = bytes + 4096;
buf.resize(bytehave + byteread);
byteread = f.read(buf.slice(bytehave, byteread), fpos);
fpos += byteread;
buf.resize(bytehave + byteread);
}
return buf.slice(bufpos, min(buf.size()-bufpos, bytes));
}
arrayview<byte> read(size_t bytes)
{
arrayview<byte> ret = peek(bytes);
if (ret.size() != bytes) return NULL;
bufpos += bytes;
crc = crc32_update(ret, crc); // TODO: perhaps it's faster if this one is calculated in large batches
return ret;
}
byte read() { return read(1)[0]; }
size_t remaining() { return buf.size()-bufpos + f.size()-fpos; }
uint32_t crc32() { return crc; }
};
class streamreader {
filebufreader f;
public:
streamreader(file& f) : f(f) {}
arrayview<byte> bytes(size_t n) { return f.read(n); }
uint8_t u8()
{
return f.read(1)[0];
}
uint16_t u16()
{
arrayview<byte> b = f.read(2);
return b[0] | b[1]<<8;
}
uint32_t u24()
{
arrayview<byte> b = f.read(3);
return b[0] | b[1]<<8 | b[2]<<16;
}
uint32_t u32()
{
arrayview<byte> b = f.read(4);
return b[0] | b[1]<<8 | b[2]<<16 | b[3]<<24;
}
// size_t bpsnum() // close to uleb128, but uleb lacks the +1 that ensures there's only one way to encode an integer
// {
// size_t ret = 0;
// size_t shift = 0;
// while (true)
// {
// uint8_t next = f.read();
// if (SIZE_MAX>>shift < (next&0x7F)) return (size_t)-1;
// size_t shifted = (next&0x7F)<<shift;
//
//#define assert_sum(a,b) do { if (SIZE_MAX-(a)<(b)) error(e_too_big); } while(0)
//#define assert_shift(a,b) do { if (SIZE_MAX>>(b)<(a)) error(e_too_big); } while(0)
//
// }
//#define decodeto(var) \
// do { \
// var=0; \
// unsigned int shift=0; \
// while (true) \
// { \
// uint8_t next=readpatch8(); \
// assert_shift(next&0x7F, shift); \
// size_t addthis=(next&0x7F)<<shift; \
// assert_sum(var, addthis); \
// var+=addthis; \
// if (next&0x80) break; \
// shift+=7; \
// assert_sum(var, 1U<<shift); \
// var+=1<<shift; \
// } \
// } while(false)
//
// arrayview<byte> b = f.peek(16);
// }
};
//Deprecated
struct mem {
mem() : ptr(NULL), len(0) {}
mem(uint8_t* ptr, size_t len) : ptr(ptr), len(len) {}
mem(arrayview<byte> v) : ptr((byte*)v.ptr()), len(v.size()) {}
arrayvieww<byte> v() { return arrayvieww<byte>(ptr, len); }
uint8_t * ptr;
size_t len;
};
}