diff options
Diffstat (limited to '')
| -rw-r--r-- | src/liblzma/api/lzma/index.h | 23 | ||||
| -rw-r--r-- | src/liblzma/common/index_decoder.c | 26 |
2 files changed, 32 insertions, 17 deletions
diff --git a/src/liblzma/api/lzma/index.h b/src/liblzma/api/lzma/index.h index da9a622a..3490e4c6 100644 --- a/src/liblzma/api/lzma/index.h +++ b/src/liblzma/api/lzma/index.h @@ -317,12 +317,13 @@ extern LZMA_API(lzma_ret) lzma_index_encoder(lzma_stream *strm, lzma_index *i) * \brief Initialize .xz Index decoder * * \param strm Pointer to properly prepared lzma_stream - * \param i Pointer to a pointer that will be made to point - * to the final decoded Index once lzma_code() has - * returned LZMA_STREAM_END. That is, - * lzma_index_decoder() always takes care of - * allocating a new lzma_index structure, and *i - * doesn't need to be initialized by the caller. + * \param i The decoded Index will be made available via + * this pointer. Initially this function will + * set *i to NULL (the old value is ignored). If + * decoding succeeds (lzma_code() returns + * LZMA_STREAM_END), *i will be set to point + * to the decoded Index, which the application + * has to later free with lzma_index_end(). * \param memlimit How much memory the resulting Index is allowed * to require. * @@ -373,11 +374,11 @@ extern LZMA_API(lzma_ret) lzma_index_buffer_encode(lzma_index *i, /** * \brief Single-call .xz Index decoder * - * \param i Pointer to a pointer that will be made to point - * to the final decoded Index if decoding is - * successful. That is, lzma_index_buffer_decode() - * always takes care of allocating a new - * lzma_index structure, and *i doesn't need to be + * \param i If decoding succeeds, *i will point to the + * decoded Index, which the application has to + * later free with lzma_index_end(). If an error + * occurs, *i will be NULL. The old value of *i + * is always ignored and thus doesn't need to be * initialized by the caller. * \param memlimit Pointer to how much memory the resulting Index * is allowed to require. The value pointed by diff --git a/src/liblzma/common/index_decoder.c b/src/liblzma/common/index_decoder.c index 51e9de38..258bf023 100644 --- a/src/liblzma/common/index_decoder.c +++ b/src/liblzma/common/index_decoder.c @@ -32,6 +32,10 @@ struct lzma_coder_s { /// Target Index lzma_index *index; + /// Pointer give by the application, which is set after + /// successful decoding. + lzma_index **index_ptr; + /// Number of Records left to decode. lzma_vli count; @@ -174,6 +178,10 @@ index_decode(lzma_coder *coder, lzma_allocator *allocator, } while (++coder->pos < 4); + // Decoding was successful, now we can let the application + // see the decoded Index. + *coder->index_ptr = coder->index; + // Make index NULL so we don't free it unintentionally. coder->index = NULL; @@ -222,15 +230,21 @@ static lzma_ret index_decoder_reset(lzma_coder *coder, lzma_allocator *allocator, lzma_index **i, uint64_t memlimit) { + // Remember the pointer given by the application. We will set it + // to point to the decoded Index only if decoding is successful. + // Before that, keep it NULL so that applications can always safely + // pass it to lzma_index_end() no matter did decoding succeed or not. + coder->index_ptr = i; + *i = NULL; + // We always allocate a new lzma_index. - *i = lzma_index_init(NULL, allocator); - if (*i == NULL) + coder->index = lzma_index_init(NULL, allocator); + if (coder->index == NULL) return LZMA_MEM_ERROR; // Initialize the rest. coder->sequence = SEQ_INDICATOR; coder->memlimit = memlimit; - coder->index = *i; coder->count = 0; // Needs to be initialized due to _memconfig(). coder->pos = 0; coder->crc32 = 0; @@ -282,7 +296,8 @@ lzma_index_buffer_decode( const uint8_t *in, size_t *in_pos, size_t in_size) { // Sanity checks - if (i == NULL || in == NULL || in_pos == NULL || *in_pos > in_size) + if (i == NULL || memlimit == NULL + || in == NULL || in_pos == NULL || *in_pos > in_size) return LZMA_PROG_ERROR; // Initialize the decoder. @@ -302,8 +317,7 @@ lzma_index_buffer_decode( } else { // Something went wrong, free the Index structure and restore // the input position. - lzma_index_end(*i, allocator); - *i = NULL; + lzma_index_end(coder.index, allocator); *in_pos = in_start; if (ret == LZMA_OK) { |