X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fsorter.h;h=ed82eb34893fad81c80350a06975d264267b56da;hb=b7b9a3d3d56430caba2f41a2e9cae8ca87dce1d6;hp=c2da83113646d0d1762786e491e67c731f9e02c7;hpb=b3fa32609de798b55eb8b6aff0310cddeb9c0d19;p=libucw.git

diff --git a/lib/sorter.h b/lib/sorter.h
index c2da8311..ed82eb34 100644
--- a/lib/sorter.h
+++ b/lib/sorter.h
@@ -1,7 +1,8 @@
 /*
- *	Sherlock Library -- Universal Sorter
+ *	UCW Library -- Universal Sorter
  *
  *	(c) 2001--2004 Martin Mares <mj@ucw.cz>
+ *	(c) 2004 Robert Spalek <robert@ucw.cz>
  *
  *	This software may be freely distributed and used according to the terms
  *	of the GNU Lesser General Public License.
@@ -18,10 +19,13 @@
  *  SORT_KEY	    [*]	data type capable of storing a single key
  *  SORT_PREFIX(x)  [*] add a name prefix (used on all global names
  *			defined by the sorter)
- *  SORT_PRESORT	include an in-core presorting pass. Beware, when in
+ *  SORT_PRESORT	include an in-core pre-sorting pass. Beware, when in
  *			the pre-sorting mode, it's quite possible that the
  *			comparison function will be called with both arguments
  *			identical.
+ *  SORT_UP_TO		a C expression, if defined, sorting is stopped after the
+ *			average run length in the file exceeds the value of this
+ *			expression (in bytes)
  *  SORT_UNIFY		merge items with identical keys
  *  SORT_UNIQUE		all items have distinct keys (checked in debug mode)
  *  SORT_REGULAR	all items are equally long and they don't contain
@@ -46,7 +50,7 @@
  *  int PREFIX_compare(SORT_KEY *a, *b)
  *			compare two keys, result like strcmp
  *  int PREFIX_fetch_key(struct fastbuf *f, SORT_KEY *k)
- *			fetch next key, returns 1=ok, 0=eof
+ *			fetch next key, returns nonzero=ok, 0=eof
  *  void PREFIX_copy_data(struct fastbuf *src, *dest, SORT_KEY *k)
  *			write just fetched key k to dest and copy all data
  *			belonging to this key from src to dest.
@@ -81,23 +85,7 @@
  *  undef'd.
  */
 
-/* Declarations of externals from sorter.c */
-
-#ifndef SORT_DECLS_READ
-#define SORT_DECLS_READ
-
-extern uns sorter_trace;
-extern uns sorter_presort_bufsize;
-extern uns sorter_stream_bufsize;
-
-extern uns sorter_pass_counter;
-
-#endif		/* !SORT_DECLS_READ */
-
-/* The sorter proper */
-
-#ifndef SORT_DECLARE_ONLY
-
+#include "lib/sorter-globals.h"
 #include "lib/fastbuf.h"
 #include <unistd.h>
 #include <fcntl.h>
@@ -116,7 +104,7 @@ extern uns sorter_pass_counter;
 #define LESS <=
 #endif
 
-#if defined(SORT_UNIQUE) && defined(DEBUG)
+#if defined(SORT_UNIQUE) && defined(DEBUG_ASSERTS)
 #define SORT_ASSERT_UNIQUE
 #endif
 
@@ -156,8 +144,12 @@ P(flush_out)(struct fastbuf *out)
   return out;
 }
 
-static void
-P(pass)(struct fastbuf **fb1, struct fastbuf **fb2)
+static uns
+P(pass)(struct fastbuf **fb1, struct fastbuf **fb2
+#ifdef SORT_UP_TO
+    , uns stop_sorting
+#endif
+)
 {
   struct fastbuf *in1 = *fb1;
   struct fastbuf *in2 = *fb2;
@@ -188,7 +180,10 @@ P(pass)(struct fastbuf **fb1, struct fastbuf **fb2)
       if (!kout || !(P(compare)(kout, ktmp) LESS 0))
 	{
 	  struct fastbuf *t;
-	  SWAP(out1, out2, t);
+#ifdef SORT_UP_TO
+	  if (!stop_sorting)
+#endif
+	    SWAP(out1, out2, t);
 	  if (!out1)
 	    out1 = bopen_tmp(sorter_stream_bufsize);
 	  run_count++;
@@ -241,6 +236,7 @@ P(pass)(struct fastbuf **fb1, struct fastbuf **fb2)
   *fb1 = P(flush_out)(out1);
   *fb2 = P(flush_out)(out2);
   sorter_pass_counter++;
+  return run_count;
 }
 
 #ifdef SORT_PRESORT
@@ -267,7 +263,7 @@ P(presort)(struct fastbuf **fb1, struct fastbuf **fb2)
   struct fastbuf *tbuf;
   uns buf_items = sorter_presort_bufsize / sizeof(SORT_KEY);
   uns run_count = 0;
-  SORT_KEY last_out, *array;
+  SORT_KEY last_out = { }, *array;
 
   ASSERT(!*fb2);
   if (buf_items < 2)
@@ -291,7 +287,10 @@ P(presort)(struct fastbuf **fb1, struct fastbuf **fb2)
       if (!run_count || P(compare)(&last_out, &array[0]) > 0)
 	{
 	  run_count++;
-	  SWAP(out1, out2, tbuf);
+#ifdef SORT_UP_TO
+	  if (sorter_presort_bufsize < (uns) SORT_UP_TO)
+#endif
+	    SWAP(out1, out2, tbuf);
 	  if (!out1)
 	    out1 = bopen_tmp(sorter_stream_bufsize);
 	}
@@ -385,7 +384,10 @@ P(presort)(struct fastbuf **fb1, struct fastbuf **fb2)
   leftover = NULL;
   while (cont)
     {
-      SWAP(out1, out2, tbuf);
+#ifdef SORT_UP_TO
+      if (sorter_presort_bufsize < SORT_UP_TO)
+#endif
+	SWAP(out1, out2, tbuf);
       if (!out1)
 	out1 = bopen_tmp(sorter_stream_bufsize);
       current = buffer;
@@ -399,7 +401,7 @@ P(presort)(struct fastbuf **fb1, struct fastbuf **fb2)
 	}
       for(;;)
 	{
-	  current = (byte *) ALIGN((addr_int_t) current, CPU_STRUCT_ALIGN);
+	  current = (byte *) ALIGN_TO((addr_int_t) current, CPU_STRUCT_ALIGN);
 	  if (current + sizeof(*this) > bufend)
 	    break;
 	  this = (SORT_NODE *) current;
@@ -509,7 +511,27 @@ struct fastbuf *fb1, struct fastbuf *fb2
   P(presort)(&fb1, &fb2);
   if (fb2)
 #endif
+#ifndef SORT_UP_TO
     do P(pass)(&fb1, &fb2); while (fb1 && fb2);
+#else
+    {
+      sh_off_t run_count, max_run_count = 0;
+      if (fb1)
+	max_run_count += bfilesize(fb1);
+      if (fb2)
+	max_run_count += bfilesize(fb2);
+#ifdef SORT_PRESORT
+      run_count = max_run_count / sorter_presort_bufsize;
+#else
+      run_count = max_run_count;
+#endif
+      if (SORT_UP_TO)
+	max_run_count /= SORT_UP_TO;
+      do
+	run_count = P(pass)(&fb1, &fb2, (run_count+1)/2 <= max_run_count);
+      while (fb1 && fb2);
+    }
+#endif
   if (!fb1)
     fb1 = bopen_tmp(sorter_stream_bufsize);
 
@@ -539,5 +561,5 @@ struct fastbuf *fb1, struct fastbuf *fb2
 #undef SORT_INPUT_FBPAIR
 #undef SORT_OUTPUT_FILE
 #undef SORT_OUTPUT_FB
-
-#endif		/* !SORT_DECLARE_ONLY */
+#undef SORT_PRESORT
+#undef SORT_UP_TO