#include "lib/mempool.h"
#include "lib/sorter/common.h"
-struct sort_bucket *
-sorter_new_bucket(struct sort_context *ctx)
-{
- return mp_alloc_zero(ctx->pool, sizeof(struct sort_bucket));
-}
+#include <string.h>
-struct fastbuf *
-sorter_open_read(struct sort_bucket *b)
+static int sorter_presort(struct sort_context *ctx, struct sort_bucket *in, struct sort_bucket *out, struct sort_bucket *out_only)
{
- /* FIXME: These functions should handle buckets with no fb and only name. */
- ASSERT(b->fb);
- return b->fb;
+ sorter_alloc_buf(ctx);
+ if (in->flags & SBF_CUSTOM_PRESORT)
+ {
+ struct fastbuf *f = sbuck_write(out);
+ return ctx->custom_presort(f, ctx->big_buf, ctx->big_buf_size); // FIXME: out_only optimization?
+ }
+ return ctx->internal_sort(ctx, in, out, out_only);
}
-struct fastbuf *
-sorter_open_write(struct sort_bucket *b)
+static inline struct sort_bucket *
+sbuck_join_to(struct sort_bucket *b)
{
- if (!b->fb)
- b->fb = bopen_tmp(sorter_stream_bufsize);
- return b->fb;
+ if (sorter_debug & SORT_DEBUG_NO_JOIN)
+ return NULL;
+
+ struct sort_bucket *out = (struct sort_bucket *) b->n.prev; // Such bucket is guaranteed to exist
+ return (out->flags & SBF_FINAL) ? out : NULL;
}
-void
-sorter_close_read(struct sort_bucket *b)
+static void
+sorter_join(struct sort_bucket *b)
{
- if (!b)
- return;
- ASSERT(b->fb);
- bclose(b->fb);
- b->fb = NULL;
+ struct sort_bucket *join = (struct sort_bucket *) b->n.prev;
+ ASSERT(join->flags & SBF_FINAL);
+ ASSERT(b->runs == 1);
+
+ if (!sbuck_has_file(join))
+ {
+ // The final bucket doesn't have any file associated yet, so replace
+ // it with the new bucket.
+ SORT_XTRACE("Replaced final bucket");
+ b->flags |= SBF_FINAL;
+ sbuck_drop(join);
+ }
+ else
+ {
+ SORT_TRACE("Copying %jd bytes to output file", (uintmax_t) sbuck_size(b));
+ struct fastbuf *src = sbuck_read(b);
+ struct fastbuf *dest = sbuck_write(join);
+ bbcopy(src, dest, ~0U);
+ sbuck_drop(b);
+ }
}
-void
-sorter_close_write(struct sort_bucket *b)
+static void
+sorter_twoway(struct sort_context *ctx, struct sort_bucket *b)
{
- if (b->fb)
+ struct sort_bucket *ins[3] = { NULL }, *outs[3] = { NULL };
+ cnode *list_pos = b->n.prev;
+ struct sort_bucket *join = sbuck_join_to(b);
+
+ if (!(sorter_debug & SORT_DEBUG_NO_PRESORT) || (b->flags & SBF_CUSTOM_PRESORT))
{
- b->size = btell(b->fb);
- brewind(b->fb);
+ SORT_TRACE("Presorting");
+ ins[0] = sbuck_new(ctx);
+ if (!sorter_presort(ctx, b, ins[0], join ? : ins[0]))
+ {
+ SORT_XTRACE("Sorted in memory");
+ if (join)
+ sbuck_drop(ins[0]);
+ else
+ clist_insert_after(&ins[0]->n, list_pos);
+ sbuck_drop(b);
+ return;
+ }
+
+ ins[1] = sbuck_new(ctx);
+ int i = 1;
+ while (sorter_presort(ctx, b, ins[i], ins[i]))
+ i = 1-i;
+ sbuck_drop(b);
}
- /* FIXME: Remove empty buckets from the list automatically? */
+ else
+ {
+ SORT_TRACE("Skipped presorting");
+ ins[0] = b;
+ }
+
+ SORT_TRACE("Main sorting");
+ do {
+ if (ins[0]->runs == 1 && ins[1]->runs == 1 && join)
+ {
+ // This is guaranteed to produce a single run, so join if possible
+ outs[0] = join;
+ outs[1] = NULL;
+ ctx->twoway_merge(ctx, ins, outs);
+ ASSERT(outs[0]->runs == 2);
+ outs[0]->runs--;
+ SORT_TRACE("Pass done (joined final run)");
+ sbuck_drop(ins[0]);
+ sbuck_drop(ins[1]);
+ return;
+ }
+ outs[0] = sbuck_new(ctx);
+ outs[1] = sbuck_new(ctx);
+ outs[2] = NULL;
+ ctx->twoway_merge(ctx, ins, outs);
+ SORT_TRACE("Pass done (%d+%d runs, %jd+%jd bytes)", outs[0]->runs, outs[1]->runs, (uintmax_t) sbuck_size(outs[0]), (uintmax_t) sbuck_size(outs[1]));
+ sbuck_drop(ins[0]);
+ sbuck_drop(ins[1]);
+ memcpy(ins, outs, 3*sizeof(struct sort_bucket *));
+ } while (sbuck_have(ins[1]));
+
+ sbuck_drop(ins[1]);
+ clist_insert_after(&ins[0]->n, list_pos);
}
void
sorter_run(struct sort_context *ctx)
{
ctx->pool = mp_new(4096);
- ASSERT(!ctx->custom_presort);
- ASSERT(!ctx->out_fb);
clist_init(&ctx->bucket_list);
/* FIXME: There should be a way how to detect size of the input file */
+ /* FIXME: Remember to test sorting of empty files */
- /* Trivial 2-way merge with no presorting (just a testing hack) */
- struct sort_bucket *bin = sorter_new_bucket(ctx);
- bin->flags = SBF_SOURCE;
- bin->fb = ctx->in_fb;
- bin->ident = "src";
- struct sort_bucket *ins[3], *outs[3];
- ins[0] = bin;
- ins[1] = NULL;
+ // Create bucket containing the source
+ struct sort_bucket *bin = sbuck_new(ctx);
+ bin->flags = SBF_SOURCE | SBF_OPEN_READ;
+ if (ctx->custom_presort)
+ bin->flags |= SBF_CUSTOM_PRESORT;
+ else
+ bin->fb = ctx->in_fb;
+ bin->ident = "in";
+ bin->size = ~(u64)0;
+ bin->hash_bits = ctx->hash_bits;
+ clist_add_tail(&ctx->bucket_list, &bin->n);
- do {
- outs[0] = sorter_new_bucket(ctx);
- outs[1] = sorter_new_bucket(ctx);
- outs[2] = NULL;
- log(L_DEBUG, "Pass...");
- ctx->twoway_merge(ctx, ins, outs);
- log(L_DEBUG, "Done (%d+%d runs)", outs[0]->runs, outs[1]->runs);
- sorter_close_write(outs[0]);
- sorter_close_write(outs[1]);
- memcpy(ins, outs, 3*sizeof(struct sort_bucket *));
- } while (ins[1]->fb);
+ // Create bucket for the output
+ struct sort_bucket *bout = sbuck_new(ctx);
+ bout->flags = SBF_FINAL;
+ bout->fb = ctx->out_fb;
+ bout->ident = "out";
+ bout->runs = 1;
+ clist_add_head(&ctx->bucket_list, &bout->n);
+
+ struct sort_bucket *b;
+ while (bout = clist_head(&ctx->bucket_list), b = clist_next(&ctx->bucket_list, &bout->n))
+ {
+ if (!sbuck_have(b))
+ sbuck_drop(b);
+ else if (b->runs == 1)
+ sorter_join(b);
+ else
+ sorter_twoway(ctx, b);
+ }
- ctx->out_fb = sorter_open_read(ins[0]);
+ sorter_free_buf(ctx);
+ sbuck_write(bout); // Force empty bucket to a file
+ SORT_XTRACE("Final size: %jd", (uintmax_t) sbuck_size(bout));
+ ctx->out_fb = sbuck_read(bout);
}
projects / libucw.git / blobdiff