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

xz/src/liblzma/common/filter_buffer_decoder.c

+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       filter_buffer_decoder.c
+/// \brief      Single-call raw decoding
+//
+//  Author:     Lasse Collin
+//
+//  This file has been put into the public domain.
+//  You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "filter_decoder.h"
+
+
+extern LZMA_API(lzma_ret)
+lzma_raw_buffer_decode(const lzma_filter *filters, lzma_allocator *allocator,
+                const uint8_t *in, size_t *in_pos, size_t in_size,
+                uint8_t *out, size_t *out_pos, size_t out_size)
+{
+        // Validate what isn't validated later in filter_common.c.
+        if (in == NULL || in_pos == NULL || *in_pos > in_size || out == NULL
+                        || out_pos == NULL || *out_pos > out_size)
+                return LZMA_PROG_ERROR;
+
+        // Initialize the decoer.
+        lzma_next_coder next = LZMA_NEXT_CODER_INIT;
+        return_if_error(lzma_raw_decoder_init(&next, allocator, filters));
+
+        // Store the positions so that we can restore them if something
+        // goes wrong.
+        const size_t in_start = *in_pos;
+        const size_t out_start = *out_pos;
+
+        // Do the actual decoding and free decoder's memory.
+        lzma_ret ret = next.code(next.coder, allocator, in, in_pos, in_size,
+                        out, out_pos, out_size, LZMA_FINISH);
+
+        if (ret == LZMA_STREAM_END) {
+                ret = LZMA_OK;
+        } else {
+                if (ret == LZMA_OK) {
+                        // Either the input was truncated or the
+                        // output buffer was too small.
+                        assert(*in_pos == in_size || *out_pos == out_size);
+
+                        if (*in_pos != in_size) {
+                                // Since input wasn't consumed completely,
+                                // the output buffer became full and is
+                                // too small.
+                                ret = LZMA_BUF_ERROR;
+
+                        } else if (*out_pos != out_size) {
+                                // Since output didn't became full, the input
+                                // has to be truncated.
+                                ret = LZMA_DATA_ERROR;
+
+                        } else {
+                                // All the input was consumed and output
+                                // buffer is full. Now we don't immediately
+                                // know the reason for the error. Try
+                                // decoding one more byte. If it succeeds,
+                                // then the output buffer was too small. If
+                                // we cannot get a new output byte, the input
+                                // is truncated.
+                                uint8_t tmp[1];
+                                size_t tmp_pos = 0;
+                                (void)next.code(next.coder, allocator,
+                                                in, in_pos, in_size,
+                                                tmp, &tmp_pos, 1, LZMA_FINISH);
+
+                                if (tmp_pos == 1)
+                                        ret = LZMA_BUF_ERROR;
+                                else
+                                        ret = LZMA_DATA_ERROR;
+                        }
+                }
+
+                // Restore the positions.
+                *in_pos = in_start;
+                *out_pos = out_start;
+        }
+
+        lzma_next_end(&next, allocator);
+
+        return ret;
+}