From 6d118a0b9def82e96afba7386ec8d7da0b59649f Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Sat, 17 Oct 2009 01:47:07 +0300 Subject: [PATCH] Add lzma_filters_copy(). This will be needed internally by liblzma once I fix a design mistake in the encoder API. This function may be useful to applications too so it's good to export it. --- src/liblzma/api/lzma/filter.h | 31 +++++++++++ src/liblzma/common/filter_common.c | 82 ++++++++++++++++++++++++++++++ 2 files changed, 113 insertions(+) diff --git a/src/liblzma/api/lzma/filter.h b/src/liblzma/api/lzma/filter.h index 8d0db96b..c3a20998 100644 --- a/src/liblzma/api/lzma/filter.h +++ b/src/liblzma/api/lzma/filter.h @@ -94,6 +94,37 @@ extern LZMA_API(lzma_bool) lzma_filter_decoder_is_supported(lzma_vli id) lzma_nothrow lzma_attr_const; +/** + * \brief Copy the filters array + * + * Copy the Filter IDs and filter-specific options from src to dest. + * Up to LZMA_FILTERS_MAX filters are copied, plus the terminating + * .id == LZMA_VLI_UNKNOWN. Thus, dest should have at least + * LZMA_FILTERS_MAX + 1 elements space unless the caller knows that + * src is smaller than that. + * + * Unless the filter-specific options is NULL, the Filter ID has to be + * supported by liblzma, because liblzma needs to know the size of every + * filter-specific options structure. The filter-specific options are not + * validated. If options is NULL, any unsupported Filter IDs are copied + * without returning an error. + * + * Old filter-specific options in dest are not freed, so dest doesn't + * need to be initialized by the caller in any way. + * + * If an error occurs, memory possibly already allocated by this function + * is always freed. + * + * \return - LZMA_OK + * - LZMA_MEM_ERROR + * - LZMA_OPTIONS_ERROR: Unsupported Filter ID and its options + * is not NULL. + * - LZMA_PROG_ERROR: src or dest is NULL. + */ +extern LZMA_API(lzma_ret) lzma_filters_dup(const lzma_filter *src, + lzma_filter *dest, lzma_allocator *allocator); + + /** * \brief Calculate rough memory requirements for raw encoder * diff --git a/src/liblzma/common/filter_common.c b/src/liblzma/common/filter_common.c index 4762460a..c839e231 100644 --- a/src/liblzma/common/filter_common.c +++ b/src/liblzma/common/filter_common.c @@ -17,6 +17,9 @@ static const struct { /// Filter ID lzma_vli id; + /// Size of the filter-specific options structure + size_t options_size; + /// True if it is OK to use this filter as non-last filter in /// the chain. bool non_last_ok; @@ -34,6 +37,7 @@ static const struct { #if defined (HAVE_ENCODER_LZMA1) || defined(HAVE_DECODER_LZMA1) { .id = LZMA_FILTER_LZMA1, + .options_size = sizeof(lzma_options_lzma), .non_last_ok = false, .last_ok = true, .changes_size = true, @@ -42,6 +46,7 @@ static const struct { #ifdef HAVE_DECODER_LZMA2 { .id = LZMA_FILTER_LZMA2, + .options_size = sizeof(lzma_options_lzma), .non_last_ok = false, .last_ok = true, .changes_size = true, @@ -50,6 +55,7 @@ static const struct { #if defined(HAVE_ENCODER_SUBBLOCK) || defined(HAVE_DECODER_SUBBLOCK) { .id = LZMA_FILTER_SUBBLOCK, + .options_size = sizeof(lzma_options_subblock), .non_last_ok = true, .last_ok = true, .changes_size = true, @@ -58,6 +64,7 @@ static const struct { #ifdef HAVE_DECODER_X86 { .id = LZMA_FILTER_X86, + .options_size = sizeof(lzma_options_bcj), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -66,6 +73,7 @@ static const struct { #if defined(HAVE_ENCODER_POWERPC) || defined(HAVE_DECODER_POWERPC) { .id = LZMA_FILTER_POWERPC, + .options_size = sizeof(lzma_options_bcj), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -74,6 +82,7 @@ static const struct { #ifdef HAVE_DECODER_IA64 { .id = LZMA_FILTER_IA64, + .options_size = sizeof(lzma_options_bcj), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -82,6 +91,7 @@ static const struct { #if defined(HAVE_ENCODER_ARM) || defined(HAVE_DECODER_ARM) { .id = LZMA_FILTER_ARM, + .options_size = sizeof(lzma_options_bcj), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -90,6 +100,7 @@ static const struct { #if defined(HAVE_ENCODER_ARMTHUMB) || defined(HAVE_DECODER_ARMTHUMB) { .id = LZMA_FILTER_ARMTHUMB, + .options_size = sizeof(lzma_options_bcj), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -98,6 +109,7 @@ static const struct { #if defined(HAVE_ENCODER_SPARC) || defined(HAVE_DECODER_SPARC) { .id = LZMA_FILTER_SPARC, + .options_size = sizeof(lzma_options_bcj), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -106,6 +118,7 @@ static const struct { #if defined(HAVE_ENCODER_DELTA) || defined(HAVE_DECODER_DELTA) { .id = LZMA_FILTER_DELTA, + .options_size = sizeof(lzma_options_delta), .non_last_ok = true, .last_ok = false, .changes_size = false, @@ -117,6 +130,75 @@ static const struct { }; +extern LZMA_API(lzma_ret) +lzma_filters_dup(const lzma_filter *src, lzma_filter *dest, + lzma_allocator *allocator) +{ + if (src == NULL || dest == NULL) + return LZMA_PROG_ERROR; + + lzma_ret ret; + size_t i; + for (i = 0; src[i].id != LZMA_VLI_UNKNOWN; ++i) { + // There must be a maximum of four filters plus + // the array terminator. + if (i == LZMA_FILTERS_MAX) { + ret = LZMA_OPTIONS_ERROR; + goto error; + } + + dest[i].id = src[i].id; + + if (src[i].options == NULL) { + dest[i].options = NULL; + } else { + // See if the filter is supported only when the + // options is not NULL. This might be convenient + // sometimes if the app is actually copying only + // a partial filter chain with a place holder ID. + // + // When options is not NULL, the Filter ID must be + // supported by us, because otherwise we don't know + // how big the options are. + size_t j; + for (j = 0; src[i].id != features[j].id; ++j) { + if (features[j].id == LZMA_VLI_UNKNOWN) { + ret = LZMA_OPTIONS_ERROR; + goto error; + } + } + + // Allocate and copy the options. + dest[i].options = lzma_alloc(features[j].options_size, + allocator); + if (dest[i].options == NULL) { + ret = LZMA_MEM_ERROR; + goto error; + } + + memcpy(dest[i].options, src[i].options, + features[j].options_size); + } + } + + // Terminate the filter array. + assert(i <= LZMA_FILTERS_MAX + 1); + dest[i].id = LZMA_VLI_UNKNOWN; + dest[i].options = NULL; + + return LZMA_OK; + +error: + // Free the options which we have already allocated. + while (i-- > 0) { + lzma_free(dest[i].options, allocator); + dest[i].options = NULL; + } + + return ret; +} + + static lzma_ret validate_chain(const lzma_filter *filters, size_t *count) {