Add an unpatched version of xz, XZ Utils, to /trunk/deps/third_party

xz/src/liblzma/delta/delta_decoder.c

+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       delta_decoder.c
+/// \brief      Delta filter decoder
+//
+//  Author:     Lasse Collin
+//
+//  This file has been put into the public domain.
+//  You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "delta_decoder.h"
+#include "delta_private.h"
+
+
+static void
+decode_buffer(lzma_coder *coder, uint8_t *buffer, size_t size)
+{
+        const size_t distance = coder->distance;
+
+        for (size_t i = 0; i < size; ++i) {
+                buffer[i] += coder->history[(distance + coder->pos) & 0xFF];
+                coder->history[coder->pos-- & 0xFF] = buffer[i];
+        }
+}
+
+
+static lzma_ret
+delta_decode(lzma_coder *coder, lzma_allocator *allocator,
+                const uint8_t *restrict in, size_t *restrict in_pos,
+                size_t in_size, uint8_t *restrict out,
+                size_t *restrict out_pos, size_t out_size, lzma_action action)
+{
+        assert(coder->next.code != NULL);
+
+        const size_t out_start = *out_pos;
+
+        const lzma_ret ret = coder->next.code(coder->next.coder, allocator,
+                        in, in_pos, in_size, out, out_pos, out_size,
+                        action);
+
+        decode_buffer(coder, out + out_start, *out_pos - out_start);
+
+        return ret;
+}
+
+
+extern lzma_ret
+lzma_delta_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
+                const lzma_filter_info *filters)
+{
+        next->code = &delta_decode;
+        return lzma_delta_coder_init(next, allocator, filters);
+}
+
+
+extern lzma_ret
+lzma_delta_props_decode(void **options, lzma_allocator *allocator,
+                const uint8_t *props, size_t props_size)
+{
+        if (props_size != 1)
+                return LZMA_OPTIONS_ERROR;
+
+        lzma_options_delta *opt
+                        = lzma_alloc(sizeof(lzma_options_delta), allocator);
+        if (opt == NULL)
+                return LZMA_MEM_ERROR;
+
+        opt->type = LZMA_DELTA_TYPE_BYTE;
+        opt->dist = props[0] + 1;
+
+        *options = opt;
+
+        return LZMA_OK;
+}