X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=lzma%2Fcommon%2Ffilter_common.c;fp=lzma%2Fcommon%2Ffilter_common.c;h=9ad5d5d8e2af7373e56807f5ddb87a5e5c037895;hb=32b8a6b26ed8843828e03e505d2256960bda0980;hp=0000000000000000000000000000000000000000;hpb=d48fc23a4bcf8ca3c406d6e8c8a6f8c6b0fa2f1e;p=zpackage

diff --git a/lzma/common/filter_common.c b/lzma/common/filter_common.c
new file mode 100644
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+++ b/lzma/common/filter_common.c
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+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       filter_common.c
+/// \brief      Filter-specific stuff common for both encoder and decoder
+//
+//  Author:     Lasse Collin
+//
+//  This file has been put into the public domain.
+//  You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "filter_common.h"
+
+
+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;
+
+	/// True if it is OK to use this filter as the last filter in
+	/// the chain.
+	bool last_ok;
+
+	/// True if the filter may change the size of the data (that is, the
+	/// amount of encoded output can be different than the amount of
+	/// uncompressed input).
+	bool changes_size;
+
+} features[] = {
+#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,
+	},
+#endif
+#if defined(HAVE_ENCODER_LZMA2) || defined(HAVE_DECODER_LZMA2)
+	{
+		.id = LZMA_FILTER_LZMA2,
+		.options_size = sizeof(lzma_options_lzma),
+		.non_last_ok = false,
+		.last_ok = true,
+		.changes_size = true,
+	},
+#endif
+#if defined(HAVE_ENCODER_X86) || defined(HAVE_DECODER_X86)
+	{
+		.id = LZMA_FILTER_X86,
+		.options_size = sizeof(lzma_options_bcj),
+		.non_last_ok = true,
+		.last_ok = false,
+		.changes_size = false,
+	},
+#endif
+#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,
+	},
+#endif
+#if defined(HAVE_ENCODER_IA64) || defined(HAVE_DECODER_IA64)
+	{
+		.id = LZMA_FILTER_IA64,
+		.options_size = sizeof(lzma_options_bcj),
+		.non_last_ok = true,
+		.last_ok = false,
+		.changes_size = false,
+	},
+#endif
+#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,
+	},
+#endif
+#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,
+	},
+#endif
+#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,
+	},
+#endif
+#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,
+	},
+#endif
+	{
+		.id = LZMA_VLI_UNKNOWN
+	}
+};
+
+
+extern LZMA_API(lzma_ret)
+lzma_filters_copy(const lzma_filter *src, lzma_filter *dest,
+		const 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)
+{
+	// There must be at least one filter.
+	if (filters == NULL || filters[0].id == LZMA_VLI_UNKNOWN)
+		return LZMA_PROG_ERROR;
+
+	// Number of non-last filters that may change the size of the data
+	// significantly (that is, more than 1-2 % or so).
+	size_t changes_size_count = 0;
+
+	// True if it is OK to add a new filter after the current filter.
+	bool non_last_ok = true;
+
+	// True if the last filter in the given chain is actually usable as
+	// the last filter. Only filters that support embedding End of Payload
+	// Marker can be used as the last filter in the chain.
+	bool last_ok = false;
+
+	size_t i = 0;
+	do {
+		size_t j;
+		for (j = 0; filters[i].id != features[j].id; ++j)
+			if (features[j].id == LZMA_VLI_UNKNOWN)
+				return LZMA_OPTIONS_ERROR;
+
+		// If the previous filter in the chain cannot be a non-last
+		// filter, the chain is invalid.
+		if (!non_last_ok)
+			return LZMA_OPTIONS_ERROR;
+
+		non_last_ok = features[j].non_last_ok;
+		last_ok = features[j].last_ok;
+		changes_size_count += features[j].changes_size;
+
+	} while (filters[++i].id != LZMA_VLI_UNKNOWN);
+
+	// There must be 1-4 filters. The last filter must be usable as
+	// the last filter in the chain. A maximum of three filters are
+	// allowed to change the size of the data.
+	if (i > LZMA_FILTERS_MAX || !last_ok || changes_size_count > 3)
+		return LZMA_OPTIONS_ERROR;
+
+	*count = i;
+	return LZMA_OK;
+}
+
+
+extern lzma_ret
+lzma_raw_coder_init(lzma_next_coder *next, const lzma_allocator *allocator,
+		const lzma_filter *options,
+		lzma_filter_find coder_find, bool is_encoder)
+{
+	// Do some basic validation and get the number of filters.
+	size_t count;
+	return_if_error(validate_chain(options, &count));
+
+	// Set the filter functions and copy the options pointer.
+	lzma_filter_info filters[LZMA_FILTERS_MAX + 1];
+	if (is_encoder) {
+		for (size_t i = 0; i < count; ++i) {
+			// The order of the filters is reversed in the
+			// encoder. It allows more efficient handling
+			// of the uncompressed data.
+			const size_t j = count - i - 1;
+
+			const lzma_filter_coder *const fc
+					= coder_find(options[i].id);
+			if (fc == NULL || fc->init == NULL)
+				return LZMA_OPTIONS_ERROR;
+
+			filters[j].id = options[i].id;
+			filters[j].init = fc->init;
+			filters[j].options = options[i].options;
+		}
+	} else {
+		for (size_t i = 0; i < count; ++i) {
+			const lzma_filter_coder *const fc
+					= coder_find(options[i].id);
+			if (fc == NULL || fc->init == NULL)
+				return LZMA_OPTIONS_ERROR;
+
+			filters[i].id = options[i].id;
+			filters[i].init = fc->init;
+			filters[i].options = options[i].options;
+		}
+	}
+
+	// Terminate the array.
+	filters[count].id = LZMA_VLI_UNKNOWN;
+	filters[count].init = NULL;
+
+	// Initialize the filters.
+	const lzma_ret ret = lzma_next_filter_init(next, allocator, filters);
+	if (ret != LZMA_OK)
+		lzma_next_end(next, allocator);
+
+	return ret;
+}
+
+
+extern uint64_t
+lzma_raw_coder_memusage(lzma_filter_find coder_find,
+		const lzma_filter *filters)
+{
+	// The chain has to have at least one filter.
+	{
+		size_t tmp;
+		if (validate_chain(filters, &tmp) != LZMA_OK)
+			return UINT64_MAX;
+	}
+
+	uint64_t total = 0;
+	size_t i = 0;
+
+	do {
+		const lzma_filter_coder *const fc
+				 = coder_find(filters[i].id);
+		if (fc == NULL)
+			return UINT64_MAX; // Unsupported Filter ID
+
+		if (fc->memusage == NULL) {
+			// This filter doesn't have a function to calculate
+			// the memory usage and validate the options. Such
+			// filters need only little memory, so we use 1 KiB
+			// as a good estimate. They also accept all possible
+			// options, so there's no need to worry about lack
+			// of validation.
+			total += 1024;
+		} else {
+			// Call the filter-specific memory usage calculation
+			// function.
+			const uint64_t usage
+					= fc->memusage(filters[i].options);
+			if (usage == UINT64_MAX)
+				return UINT64_MAX; // Invalid options
+
+			total += usage;
+		}
+	} while (filters[++i].id != LZMA_VLI_UNKNOWN);
+
+	// Add some fixed amount of extra. It's to compensate memory usage
+	// of Stream, Block etc. coders, malloc() overhead, stack etc.
+	return total + LZMA_MEMUSAGE_BASE;
+}