diff options
| author | John Schoenick <[email protected]> | 2015-09-09 18:35:41 -0700 |
|---|---|---|
| committer | John Schoenick <[email protected]> | 2015-09-09 18:35:41 -0700 |
| commit | 0d8dceea4310fde5706b3ce1c70609d72a38efdf (patch) | |
| tree | c831ef32c2c801a5c5a80401736b52c7b5a528ec /mp/src/utils/lzma/C/Delta.c | |
| parent | Updated the SDK with the latest code from the TF and HL2 branches. (diff) | |
| download | source-sdk-2013-master.tar.xz source-sdk-2013-master.zip | |
Diffstat (limited to 'mp/src/utils/lzma/C/Delta.c')
| -rw-r--r-- | mp/src/utils/lzma/C/Delta.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/mp/src/utils/lzma/C/Delta.c b/mp/src/utils/lzma/C/Delta.c new file mode 100644 index 00000000..e3edd21e --- /dev/null +++ b/mp/src/utils/lzma/C/Delta.c @@ -0,0 +1,64 @@ +/* Delta.c -- Delta converter +2009-05-26 : Igor Pavlov : Public domain */ + +#include "Precomp.h" + +#include "Delta.h" + +void Delta_Init(Byte *state) +{ + unsigned i; + for (i = 0; i < DELTA_STATE_SIZE; i++) + state[i] = 0; +} + +static void MyMemCpy(Byte *dest, const Byte *src, unsigned size) +{ + unsigned i; + for (i = 0; i < size; i++) + dest[i] = src[i]; +} + +void Delta_Encode(Byte *state, unsigned delta, Byte *data, SizeT size) +{ + Byte buf[DELTA_STATE_SIZE]; + unsigned j = 0; + MyMemCpy(buf, state, delta); + { + SizeT i; + for (i = 0; i < size;) + { + for (j = 0; j < delta && i < size; i++, j++) + { + Byte b = data[i]; + data[i] = (Byte)(b - buf[j]); + buf[j] = b; + } + } + } + if (j == delta) + j = 0; + MyMemCpy(state, buf + j, delta - j); + MyMemCpy(state + delta - j, buf, j); +} + +void Delta_Decode(Byte *state, unsigned delta, Byte *data, SizeT size) +{ + Byte buf[DELTA_STATE_SIZE]; + unsigned j = 0; + MyMemCpy(buf, state, delta); + { + SizeT i; + for (i = 0; i < size;) + { + for (j = 0; j < delta && i < size; i++, j++) + { + buf[j] = data[i] = (Byte)(buf[j] + data[i]); + } + } + } + if (j == delta) + j = 0; + MyMemCpy(state, buf + j, delta - j); + MyMemCpy(state + delta - j, buf, j); +} |