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| author | wolfbeast <mcwerewolf@wolfbeast.com> | 2019-04-05 20:01:10 +0200 |
|---|---|---|
| committer | wolfbeast <mcwerewolf@wolfbeast.com> | 2019-04-05 20:01:10 +0200 |
| commit | c3b63b831cd2c64700e875b28540212c7c881ac6 (patch) | |
| tree | edd98fcbd2004d3b562904f822bf6c3322fc7f52 /other-licenses/7zstub/src/C/Delta.c | |
| parent | d432e068a21c815d5d5e7bcbc1cc8c6e77a7d1e0 (diff) | |
| parent | cc07da9cb4d6e7a53f8d953427ffc2bca2e0c2df (diff) | |
| download | UXP-c3b63b831cd2c64700e875b28540212c7c881ac6.tar UXP-c3b63b831cd2c64700e875b28540212c7c881ac6.tar.gz UXP-c3b63b831cd2c64700e875b28540212c7c881ac6.tar.lz UXP-c3b63b831cd2c64700e875b28540212c7c881ac6.tar.xz UXP-c3b63b831cd2c64700e875b28540212c7c881ac6.zip | |
Merge branch 'master' into 816
Diffstat (limited to 'other-licenses/7zstub/src/C/Delta.c')
| -rw-r--r-- | other-licenses/7zstub/src/C/Delta.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/C/Delta.c b/other-licenses/7zstub/src/C/Delta.c new file mode 100644 index 000000000..6cbbe4601 --- /dev/null +++ b/other-licenses/7zstub/src/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);
+}
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