]> wimlib.net Git - wimlib/blobdiff - src/lzms-compress.c
lzms_init_compressor(): Do not zero end of window
[wimlib] / src / lzms-compress.c
index 6df108061e8518d22a3d2e238d8d1d6484e98b86..a18da5781842b12f892b51ef94eebbe9e7f433f1 100644 (file)
@@ -33,7 +33,6 @@
 #endif
 
 #include "wimlib.h"
-#include "wimlib/assert.h"
 #include "wimlib/compiler.h"
 #include "wimlib/compressor_ops.h"
 #include "wimlib/compress_common.h"
@@ -140,9 +139,7 @@ struct lzms_range_encoder {
        struct lzms_probability_entry prob_entries[LZMS_MAX_NUM_STATES];
 };
 
-/* Structure used for Huffman encoding, optionally encoding larger "values" as a
- * Huffman symbol specifying a slot and a slot-dependent number of extra bits.
- * */
+/* Structure used for Huffman encoding.  */
 struct lzms_huffman_encoder {
 
        /* Bitstream to write Huffman-encoded symbols and verbatim bits to.
@@ -150,9 +147,6 @@ struct lzms_huffman_encoder {
         */
        struct lzms_output_bitstream *os;
 
-       /* Pointer to the slot base table to use.  */
-       const u32 *slot_base_tab;
-
        /* Number of symbols that have been written using this code far.  Reset
         * to 0 whenever the code is rebuilt.  */
        u32 num_syms_written;
@@ -195,7 +189,8 @@ struct lzms_compressor {
        /* Suffix array match-finder.  */
        struct lz_sarray lz_sarray;
 
-       struct raw_match matches[64];
+       /* Temporary space to store found matches.  */
+       struct raw_match *matches;
 
        /* Match-chooser.  */
        struct lz_match_chooser mc;
@@ -460,29 +455,36 @@ lzms_huffman_encode_symbol(struct lzms_huffman_encoder *enc, u32 sym)
        }
 }
 
-/* Encode a number as a Huffman symbol specifying a slot, plus a number of
- * slot-dependent extra bits.  */
 static void
-lzms_encode_value(struct lzms_huffman_encoder *enc, u32 value)
+lzms_encode_length(struct lzms_huffman_encoder *enc, u32 length)
 {
        unsigned slot;
        unsigned num_extra_bits;
        u32 extra_bits;
 
-       LZMS_ASSERT(enc->slot_base_tab != NULL);
+       slot = lzms_get_length_slot(length);
 
-       slot = lzms_get_slot(value, enc->slot_base_tab, enc->num_syms);
+       num_extra_bits = lzms_extra_length_bits[slot];
 
-       /* Get the number of extra bits needed to represent the range of values
-        * that share the slot.  */
-       num_extra_bits = bsr32(enc->slot_base_tab[slot + 1] -
-                              enc->slot_base_tab[slot]);
+       extra_bits = length - lzms_length_slot_base[slot];
 
-       /* Calculate the extra bits as the offset from the slot base.  */
-       extra_bits = value - enc->slot_base_tab[slot];
+       lzms_huffman_encode_symbol(enc, slot);
+       lzms_output_bitstream_put_bits(enc->os, extra_bits, num_extra_bits);
+}
+
+static void
+lzms_encode_offset(struct lzms_huffman_encoder *enc, u32 offset)
+{
+       unsigned slot;
+       unsigned num_extra_bits;
+       u32 extra_bits;
+
+       slot = lzms_get_position_slot(offset);
+
+       num_extra_bits = lzms_extra_position_bits[slot];
+
+       extra_bits = offset - lzms_position_slot_base[slot];
 
-       /* Output the slot (Huffman-encoded), then the extra bits (verbatim).
-        */
        lzms_huffman_encode_symbol(enc, slot);
        lzms_output_bitstream_put_bits(enc->os, extra_bits, num_extra_bits);
 }
@@ -558,7 +560,7 @@ lzms_encode_lz_match(struct lzms_compressor *ctx, u32 length, u32 offset)
                lzms_range_encode_bit(&ctx->lz_match_range_encoder, 0);
 
                /* Encode the match offset.  */
-               lzms_encode_value(&ctx->lz_offset_encoder, offset);
+               lzms_encode_offset(&ctx->lz_offset_encoder, offset);
        } else {
                int i;
 
@@ -583,7 +585,7 @@ lzms_encode_lz_match(struct lzms_compressor *ctx, u32 length, u32 offset)
        }
 
        /* Encode the match length.  */
-       lzms_encode_value(&ctx->length_encoder, length);
+       lzms_encode_length(&ctx->length_encoder, length);
 
        /* Save the match offset for later insertion at the front of the LZ
         * match offset LRU queue.  */
@@ -654,7 +656,7 @@ lzms_lz_match_cost_fast(input_idx_t length, input_idx_t offset, const void *_lru
 /*#define LZMS_RC_COSTS_USE_FLOATING_POINT*/
 
 static u32
-lzms_rc_costs[LZMS_PROBABILITY_MAX];
+lzms_rc_costs[LZMS_PROBABILITY_MAX + 1];
 
 #ifdef LZMS_RC_COSTS_USE_FLOATING_POINT
 #  include <math.h>
@@ -684,7 +686,7 @@ lzms_do_init_rc_costs(void)
         * really interpreted as 1 / 64 and 64 / 64 is really interpreted as
         * 63 / 64.
         */
-       for (u32 i = 0; i < LZMS_PROBABILITY_MAX; i++) {
+       for (u32 i = 0; i <= LZMS_PROBABILITY_MAX; i++) {
                u32 prob = i;
 
                if (prob == 0)
@@ -718,7 +720,7 @@ lzms_init_rc_costs(void)
        static bool done = false;
        static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 
-       if (!done) {
+       if (unlikely(!done)) {
                pthread_mutex_lock(&mutex);
                if (!done) {
                        lzms_do_init_rc_costs();
@@ -747,11 +749,6 @@ lzms_rc_bit_cost(const struct lzms_range_encoder *enc, u8 *cur_state, int bit)
 
        *cur_state = (*cur_state << 1) | bit;
 
-       if (prob_zero == 0)
-               prob_zero = 1;
-       else if (prob_zero == LZMS_PROBABILITY_MAX)
-               prob_zero = LZMS_PROBABILITY_MAX - 1;
-
        if (bit == 0)
                prob_correct = prob_zero;
        else
@@ -766,20 +763,18 @@ lzms_huffman_symbol_cost(const struct lzms_huffman_encoder *enc, u32 sym)
        return enc->lens[sym] << LZMS_COST_SHIFT;
 }
 
-/* Compute the cost to encode a number with lzms_encode_value().  */
 static u32
-lzms_value_cost(const struct lzms_huffman_encoder *enc, u32 value)
+lzms_offset_cost(const struct lzms_huffman_encoder *enc, u32 offset)
 {
        u32 slot;
        u32 num_extra_bits;
        u32 cost = 0;
 
-       slot = lzms_get_slot(value, enc->slot_base_tab, enc->num_syms);
+       slot = lzms_get_position_slot(offset);
 
        cost += lzms_huffman_symbol_cost(enc, slot);
 
-       num_extra_bits = bsr32(enc->slot_base_tab[slot + 1] -
-                              enc->slot_base_tab[slot]);
+       num_extra_bits = lzms_extra_position_bits[slot];
 
        cost += num_extra_bits << LZMS_COST_SHIFT;
 
@@ -787,41 +782,33 @@ lzms_value_cost(const struct lzms_huffman_encoder *enc, u32 value)
 }
 
 static u32
-lzms_get_matches(struct lzms_compressor *ctx,
-                const struct lzms_adaptive_state *state,
-                struct raw_match **matches_ret)
+lzms_length_cost(const struct lzms_huffman_encoder *enc, u32 length)
 {
-       u32 num_matches;
-       struct raw_match *matches = ctx->matches;
+       u32 slot;
+       u32 num_extra_bits;
+       u32 cost = 0;
 
-       num_matches = lz_sarray_get_matches(&ctx->lz_sarray,
-                                           matches,
-                                           lzms_lz_match_cost_fast,
-                                           &state->lru);
-#if 0
-       fprintf(stderr, "Pos %u: %u matches\n",
-               lz_sarray_get_pos(&ctx->lz_sarray) - 1, num_matches);
-       for (u32 i = 0; i < num_matches; i++)
-               fprintf(stderr, "\tLen %u Offset %u\n", matches[i].len, matches[i].offset);
-#endif
+       slot = lzms_get_length_slot(length);
+
+       cost += lzms_huffman_symbol_cost(enc, slot);
 
-#ifdef ENABLE_LZMS_DEBUG
-       LZMS_ASSERT(lz_sarray_get_pos(&ctx->lz_sarray) > 0);
-       u32 curpos = lz_sarray_get_pos(&ctx->lz_sarray) - 1;
-       for (u32 i = 0; i < num_matches; i++) {
-               LZMS_ASSERT(matches[i].len <= ctx->window_size - curpos);
-               LZMS_ASSERT(matches[i].offset > 0);
-               LZMS_ASSERT(matches[i].offset <= curpos);
-               LZMS_ASSERT(!memcmp(&ctx->window[curpos],
-                                   &ctx->window[curpos - matches[i].offset],
-                                   matches[i].len));
-               if (i < num_matches - 1)
-                       LZMS_ASSERT(matches[i].len > matches[i + 1].len);
+       num_extra_bits = lzms_extra_length_bits[slot];
 
-       }
-#endif
-       *matches_ret = matches;
-       return num_matches;
+       cost += num_extra_bits << LZMS_COST_SHIFT;
+
+       return cost;
+}
+
+static u32
+lzms_get_matches(struct lzms_compressor *ctx,
+                const struct lzms_adaptive_state *state,
+                struct raw_match **matches_ret)
+{
+       *matches_ret = ctx->matches;
+       return lz_sarray_get_matches(&ctx->lz_sarray,
+                                    ctx->matches,
+                                    lzms_lz_match_cost_fast,
+                                    &state->lru);
 }
 
 static void
@@ -873,7 +860,7 @@ lzms_get_lz_match_cost(struct lzms_compressor *ctx,
                cost += lzms_rc_bit_cost(&ctx->lz_match_range_encoder,
                                         &state->lz_match_state, 0);
 
-               cost += lzms_value_cost(&ctx->lz_offset_encoder, offset);
+               cost += lzms_offset_cost(&ctx->lz_offset_encoder, offset);
        } else {
                int i;
 
@@ -895,7 +882,7 @@ lzms_get_lz_match_cost(struct lzms_compressor *ctx,
                        state->lru.recent_offsets[i] = state->lru.recent_offsets[i + 1];
        }
 
-       cost += lzms_value_cost(&ctx->length_encoder, length);
+       cost += lzms_length_cost(&ctx->length_encoder, length);
 
        state->lru.upcoming_offset = offset;
        lzms_update_lz_lru_queues(&state->lru);
@@ -980,12 +967,10 @@ lzms_init_range_encoder(struct lzms_range_encoder *enc,
 static void
 lzms_init_huffman_encoder(struct lzms_huffman_encoder *enc,
                          struct lzms_output_bitstream *os,
-                         const u32 *slot_base_tab,
                          unsigned num_syms,
                          unsigned rebuild_freq)
 {
        enc->os = os;
-       enc->slot_base_tab = slot_base_tab;
        enc->num_syms_written = 0;
        enc->rebuild_freq = rebuild_freq;
        enc->num_syms = num_syms;
@@ -1008,7 +993,6 @@ lzms_init_compressor(struct lzms_compressor *ctx, const u8 *udata, u32 ulen,
 
        /* Copy the uncompressed data into the @ctx->window buffer.  */
        memcpy(ctx->window, udata, ulen);
-       memset(&ctx->window[ulen], 0, 8);
        ctx->cur_window_pos = 0;
        ctx->window_size = ulen;
 
@@ -1028,23 +1012,23 @@ lzms_init_compressor(struct lzms_compressor *ctx, const u8 *udata, u32 ulen,
        /* Initialize Huffman encoders for each alphabet used in the compressed
         * representation.  */
        lzms_init_huffman_encoder(&ctx->literal_encoder, &ctx->os,
-                                 NULL, LZMS_NUM_LITERAL_SYMS,
+                                 LZMS_NUM_LITERAL_SYMS,
                                  LZMS_LITERAL_CODE_REBUILD_FREQ);
 
        lzms_init_huffman_encoder(&ctx->lz_offset_encoder, &ctx->os,
-                                 lzms_position_slot_base, num_position_slots,
+                                 num_position_slots,
                                  LZMS_LZ_OFFSET_CODE_REBUILD_FREQ);
 
        lzms_init_huffman_encoder(&ctx->length_encoder, &ctx->os,
-                                 lzms_length_slot_base, LZMS_NUM_LEN_SYMS,
+                                 LZMS_NUM_LEN_SYMS,
                                  LZMS_LENGTH_CODE_REBUILD_FREQ);
 
        lzms_init_huffman_encoder(&ctx->delta_offset_encoder, &ctx->os,
-                                 lzms_position_slot_base, num_position_slots,
+                                 num_position_slots,
                                  LZMS_DELTA_OFFSET_CODE_REBUILD_FREQ);
 
        lzms_init_huffman_encoder(&ctx->delta_power_encoder, &ctx->os,
-                                 NULL, LZMS_NUM_DELTA_POWER_SYMS,
+                                 LZMS_NUM_DELTA_POWER_SYMS,
                                  LZMS_DELTA_POWER_CODE_REBUILD_FREQ);
 
        /* Initialize range encoders, all of which wrap around the same
@@ -1070,7 +1054,7 @@ lzms_init_compressor(struct lzms_compressor *ctx, const u8 *udata, u32 ulen,
                                        &ctx->rc, LZMS_NUM_DELTA_REPEAT_MATCH_STATES);
 
        /* Initialize LRU match information.  */
-        lzms_init_lru_queues(&ctx->lru);
+       lzms_init_lru_queues(&ctx->lru);
 }
 
 /* Flush the output streams, prepare the final compressed data, and return its
@@ -1162,8 +1146,9 @@ lzms_compress(const void *uncompressed_data, size_t uncompressed_size,
 
        /* Compute and encode a literal/match sequence that decompresses to the
         * preprocessed data.  */
+#if 1
        lzms_normal_encode(ctx);
-#if 0
+#else
        lzms_fast_encode(ctx);
 #endif
 
@@ -1233,13 +1218,14 @@ lzms_free_compressor(void *_ctx)
 #if 0
                FREE(ctx->prev_tab);
 #endif
+               FREE(ctx->matches);
                lz_sarray_destroy(&ctx->lz_sarray);
                lz_match_chooser_destroy(&ctx->mc);
                FREE(ctx);
        }
 }
 
-static const struct wimlib_lzms_compressor_params default_params = {
+static const struct wimlib_lzms_compressor_params lzms_default = {
        .hdr = sizeof(struct wimlib_lzms_compressor_params),
        .min_match_length = 2,
        .max_match_length = UINT32_MAX,
@@ -1249,37 +1235,36 @@ static const struct wimlib_lzms_compressor_params default_params = {
        .optim_array_length = 1024,
 };
 
+static const struct wimlib_lzms_compressor_params *
+lzms_get_params(const struct wimlib_compressor_params_header *_params)
+{
+       const struct wimlib_lzms_compressor_params *params =
+               (const struct wimlib_lzms_compressor_params*)_params;
+
+       if (params == NULL)
+               params = &lzms_default;
+
+       return params;
+}
+
 static int
 lzms_create_compressor(size_t max_block_size,
                       const struct wimlib_compressor_params_header *_params,
                       void **ctx_ret)
 {
        struct lzms_compressor *ctx;
-       const struct wimlib_lzms_compressor_params *params;
+       const struct wimlib_lzms_compressor_params *params = lzms_get_params(_params);
 
        if (max_block_size == 0 || max_block_size >= INT32_MAX) {
                LZMS_DEBUG("Invalid max_block_size (%u)", max_block_size);
                return WIMLIB_ERR_INVALID_PARAM;
        }
 
-       if (_params)
-               params = (const struct wimlib_lzms_compressor_params*)_params;
-       else
-               params = &default_params;
-
-       if (params->max_match_length < params->min_match_length ||
-           params->min_match_length < 2 ||
-           params->optim_array_length == 0 ||
-           min(params->max_match_length, params->nice_match_length) > 65536) {
-               LZMS_DEBUG("Invalid compression parameter!");
-               return WIMLIB_ERR_INVALID_PARAM;
-       }
-
        ctx = CALLOC(1, sizeof(struct lzms_compressor));
        if (ctx == NULL)
                goto oom;
 
-       ctx->window = MALLOC(max_block_size + 8);
+       ctx->window = MALLOC(max_block_size);
        if (ctx->window == NULL)
                goto oom;
 
@@ -1289,6 +1274,13 @@ lzms_create_compressor(size_t max_block_size,
                goto oom;
 #endif
 
+       ctx->matches = MALLOC(min(params->max_match_length -
+                                       params->min_match_length + 1,
+                                 params->max_matches_per_pos) *
+                               sizeof(ctx->matches[0]));
+       if (ctx->matches == NULL)
+               goto oom;
+
        if (!lz_sarray_init(&ctx->lz_sarray, max_block_size,
                            params->min_match_length,
                            params->max_match_length,
@@ -1302,8 +1294,8 @@ lzms_create_compressor(size_t max_block_size,
                                   params->max_match_length))
                goto oom;
 
-       /* Initialize position and length slot bases if not done already.  */
-       lzms_init_slot_bases();
+       /* Initialize position and length slot data if not done already.  */
+       lzms_init_slots();
 
        /* Initialize range encoding cost table if not done already.  */
        lzms_init_rc_costs();
@@ -1318,7 +1310,46 @@ oom:
        return WIMLIB_ERR_NOMEM;
 }
 
+static u64
+lzms_get_needed_memory(size_t max_block_size,
+                      const struct wimlib_compressor_params_header *_params)
+{
+       const struct wimlib_lzms_compressor_params *params = lzms_get_params(_params);
+
+       u64 size = 0;
+
+       size += max_block_size;
+       size += sizeof(struct lzms_compressor);
+       size += lz_sarray_get_needed_memory(max_block_size);
+       size += lz_match_chooser_get_needed_memory(params->optim_array_length,
+                                                  params->nice_match_length,
+                                                  params->max_match_length);
+       size += min(params->max_match_length -
+                   params->min_match_length + 1,
+                   params->max_matches_per_pos) *
+               sizeof(((struct lzms_compressor*)0)->matches[0]);
+       return size;
+}
+
+static bool
+lzms_params_valid(const struct wimlib_compressor_params_header *_params)
+{
+       const struct wimlib_lzms_compressor_params *params =
+               (const struct wimlib_lzms_compressor_params*)_params;
+
+       if (params->hdr.size != sizeof(*params) ||
+           params->max_match_length < params->min_match_length ||
+           params->min_match_length < 2 ||
+           params->optim_array_length == 0 ||
+           min(params->max_match_length, params->nice_match_length) > 65536)
+               return false;
+
+       return true;
+}
+
 const struct compressor_ops lzms_compressor_ops = {
+       .params_valid       = lzms_params_valid,
+       .get_needed_memory  = lzms_get_needed_memory,
        .create_compressor  = lzms_create_compressor,
        .compress           = lzms_compress,
        .free_compressor    = lzms_free_compressor,