X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=isamc%2Fisamc.c;h=6d64d7940e74c862eb7a80538c9ef24c6bee1f42;hb=3db15cf883ad80b6a4b0e960f3c3b59c86b59c6b;hp=6401c63380bb4f937b05b47efd82c7890336ffe1;hpb=7107ed62f445c83a9c79b375158442f6b03f3ce6;p=idzebra-moved-to-github.git

diff --git a/isamc/isamc.c b/isamc/isamc.c
index 6401c63..6d64d79 100644
--- a/isamc/isamc.c
+++ b/isamc/isamc.c
@@ -4,10 +4,27 @@
  * Sebastian Hammer, Adam Dickmeiss
  *
  * $Log: isamc.c,v $
- * Revision 1.4  1996-11-01 13:36:46  adam
+ * Revision 1.8  1997-09-17 12:19:20  adam
+ * Zebra version corresponds to YAZ version 1.4.
+ * Changed Zebra server so that it doesn't depend on global common_resource.
+ *
+ * Revision 1.7  1997/02/12 20:42:43  adam
+ * Bug fix: during isc_merge operations, some pages weren't marked dirty
+ * even though they should be. At this point the merge operation marks
+ * a page dirty if the previous page changed at all. A better approach is
+ * to mark it dirty if the last key written changed in previous page.
+ *
+ * Revision 1.6  1996/11/08 11:15:29  adam
+ * Number of keys in chain are stored in first block and the function
+ * to retrieve this information, isc_pp_num is implemented.
+ *
+ * Revision 1.5  1996/11/04 14:08:57  adam
+ * Optimized free block usage.
+ *
+ * Revision 1.4  1996/11/01 13:36:46  adam
  * New element, max_blocks_mem, that control how many blocks of max size
  * to store in memory during isc_merge.
- * Function isc_merge now ignoreds delete/update of identical keys and
+ * Function isc_merge now ignores delete/update of identical keys and
  * the proper blocks are then non-dirty and not written in flush_blocks.
  *
  * Revision 1.3  1996/11/01  08:59:14  adam
@@ -24,7 +41,6 @@
 /* 
  * TODO:
  *   Reduction to lower categories in isc_merge
- *   Implementation of isc_numkeys
  */
 #include <stdlib.h>
 #include <assert.h>
@@ -34,6 +50,9 @@
 #include <log.h>
 #include "isamc-p.h"
 
+static void release_fc (ISAMC is, int cat);
+static void init_fc (ISAMC is, int cat);
+
 ISAMC_M isc_getmethod (void)
 {
     static struct ISAMC_filecat_s def_cat[] = {
@@ -41,7 +60,6 @@ ISAMC_M isc_getmethod (void)
         {  512,   490,   100,    20 },
         { 4096,  3950,  1000,    20 },
         {32768, 32000, 10000,     0 },
-        {    0,     0,     0,     0 }
     };
     ISAMC_M m = xmalloc (sizeof(*m));
     m->filecat = def_cat;
@@ -52,7 +70,7 @@ ISAMC_M isc_getmethod (void)
 
     m->compare_item = NULL;
 
-    m->debug = 0;
+    m->debug = 1;
 
     m->max_blocks_mem = 10;
 
@@ -60,11 +78,11 @@ ISAMC_M isc_getmethod (void)
 }
 
 
-ISAMC isc_open (const char *name, int writeflag, ISAMC_M method)
+ISAMC isc_open (BFiles bfs, const char *name, int writeflag, ISAMC_M method)
 {
     ISAMC is;
     ISAMC_filecat filecat;
-    int i;
+    int i = 0;
     int max_buf_size = 0;
 
     is = xmalloc (sizeof(*is));
@@ -77,7 +95,7 @@ ISAMC isc_open (const char *name, int writeflag, ISAMC_M method)
     /* determine number of block categories */
     if (is->method->debug)
         logf (LOG_LOG, "isc: bsize  ifill  mfill mblocks");
-    for (i = 0; filecat[i].bsize; i++)
+    do
     {
         if (is->method->debug)
             logf (LOG_LOG, "isc:%6d %6d %6d %6d",
@@ -85,7 +103,7 @@ ISAMC isc_open (const char *name, int writeflag, ISAMC_M method)
                   filecat[i].mfill, filecat[i].mblocks);
         if (max_buf_size < filecat[i].mblocks * filecat[i].bsize)
             max_buf_size = filecat[i].mblocks * filecat[i].bsize;
-    }
+    } while (filecat[i++].mblocks);
     is->no_files = i;
     is->max_cat = --i;
     /* max_buf_size is the larget buffer to be used during merge */
@@ -99,8 +117,8 @@ ISAMC isc_open (const char *name, int writeflag, ISAMC_M method)
     is->files = xmalloc (sizeof(*is->files)*is->no_files);
     if (writeflag)
     {
-        is->merge_buf = xmalloc (max_buf_size+128);
-	memset (is->merge_buf, 0, max_buf_size+128);
+        is->merge_buf = xmalloc (max_buf_size+256);
+	memset (is->merge_buf, 0, max_buf_size+256);
     }
     else
         is->merge_buf = NULL;
@@ -109,7 +127,7 @@ ISAMC isc_open (const char *name, int writeflag, ISAMC_M method)
         char fname[512];
 
         sprintf (fname, "%s%c", name, i+'A');
-        is->files[i].bf = bf_open (fname, is->method->filecat[i].bsize,
+        is->files[i].bf = bf_open (bfs, fname, is->method->filecat[i].bsize,
                                    writeflag);
         is->files[i].head_is_dirty = 0;
         if (!bf_read (is->files[i].bf, 0, 0, sizeof(ISAMC_head),
@@ -124,6 +142,8 @@ ISAMC isc_open (const char *name, int writeflag, ISAMC_M method)
         is->files[i].no_allocated = 0;
         is->files[i].no_released = 0;
         is->files[i].no_remap = 0;
+
+        init_fc (is, i);
     }
     return is;
 }
@@ -136,6 +156,7 @@ int isc_close (ISAMC is)
         logf (LOG_LOG, "isc:  writes   reads skipped   alloc released  remap");
     for (i = 0; i<is->no_files; i++)
     {
+        release_fc (is, i);
         assert (is->files[i].bf);
         if (is->files[i].head_is_dirty)
             bf_write (is->files[i].bf, 0, 0, sizeof(ISAMC_head),
@@ -148,6 +169,7 @@ int isc_close (ISAMC is)
                   is->files[i].no_allocated,
                   is->files[i].no_released,
                   is->files[i].no_remap);
+        xfree (is->files[i].fc_list);
         bf_close (is->files[i].bf);
     }
     xfree (is->files);
@@ -159,8 +181,6 @@ int isc_close (ISAMC is)
 int isc_read_block (ISAMC is, int cat, int pos, char *dst)
 {
     ++(is->files[cat].no_reads);
-    if (is->method->debug > 2)
-        logf (LOG_LOG, "isc: read_block %d %d", cat, pos);
     return bf_read (is->files[cat].bf, pos, 0, 0, dst);
 }
 
@@ -175,16 +195,17 @@ int isc_write_block (ISAMC is, int cat, int pos, char *src)
 int isc_write_dblock (ISAMC is, int cat, int pos, char *src,
                       int nextpos, int offset)
 {
-    int xoffset = offset + 2*sizeof(int);
+    unsigned short size = offset + ISAMC_BLOCK_OFFSET_N;
     if (is->method->debug > 2)
         logf (LOG_LOG, "isc: write_dblock. size=%d nextpos=%d",
-              offset, nextpos);
-    memcpy (src - sizeof(int)*2, &nextpos, sizeof(int));
-    memcpy (src - sizeof(int), &xoffset, sizeof(int));
-    return isc_write_block (is, cat, pos, src - sizeof(int)*2);
+              (int) size, nextpos);
+    src -= ISAMC_BLOCK_OFFSET_N;
+    memcpy (src, &nextpos, sizeof(int));
+    memcpy (src + sizeof(int), &size, sizeof(size));
+    return isc_write_block (is, cat, pos, src);
 }
 
-int isc_alloc_block (ISAMC is, int cat)
+static int alloc_block (ISAMC is, int cat)
 {
     int block;
     char buf[sizeof(int)];
@@ -198,12 +219,31 @@ int isc_alloc_block (ISAMC is, int cat)
     }
     else
         block = (is->files[cat].head.lastblock)++;
-    if (is->method->debug > 2)
+    return block;
+}
+
+int isc_alloc_block (ISAMC is, int cat)
+{
+    int block = 0;
+
+    if (is->files[cat].fc_list)
+    {
+        int j, nb;
+        for (j = 0; j < is->files[cat].fc_max; j++)
+            if ((nb = is->files[cat].fc_list[j]) && (!block || nb < block))
+            {
+                is->files[cat].fc_list[j] = 0;
+                break;
+            }
+    }
+    if (!block)
+        block = alloc_block (is, cat);
+    if (is->method->debug > 3)
         logf (LOG_LOG, "isc: alloc_block in cat %d: %d", cat, block);
     return block;
 }
 
-void isc_release_block (ISAMC is, int cat, int pos)
+static void release_block (ISAMC is, int cat, int pos)
 {
     char buf[sizeof(int)];
    
@@ -212,8 +252,45 @@ void isc_release_block (ISAMC is, int cat, int pos)
     memcpy (buf, &is->files[cat].head.freelist, sizeof(int));
     is->files[cat].head.freelist = pos;
     bf_write (is->files[cat].bf, pos, 0, sizeof(int), buf);
-    if (is->method->debug > 2)
+}
+
+void isc_release_block (ISAMC is, int cat, int pos)
+{
+    if (is->method->debug > 3)
         logf (LOG_LOG, "isc: release_block in cat %d: %d", cat, pos);
+    if (is->files[cat].fc_list)
+    {
+        int j;
+        for (j = 0; j<is->files[cat].fc_max; j++)
+            if (!is->files[cat].fc_list[j])
+            {
+                is->files[cat].fc_list[j] = pos;
+                return;
+            }
+    }
+    release_block (is, cat, pos);
+}
+
+static void init_fc (ISAMC is, int cat)
+{
+    int j = 100;
+        
+    is->files[cat].fc_max = j;
+    is->files[cat].fc_list = xmalloc (sizeof(*is->files[0].fc_list) * j);
+    while (--j >= 0)
+        is->files[cat].fc_list[j] = 0;
+}
+
+static void release_fc (ISAMC is, int cat)
+{
+    int b, j = is->files[cat].fc_max;
+
+    while (--j >= 0)
+        if ((b = is->files[cat].fc_list[j]))
+        {
+            release_block (is, cat, b);
+            is->files[cat].fc_list[j] = 0;
+        }
 }
 
 void isc_pp_close (ISAMC_PP pp)
@@ -231,21 +308,40 @@ ISAMC_PP isc_pp_open (ISAMC is, ISAMC_P ipos)
     char *src;
    
     pp->cat = isc_type(ipos);
-    pp->next = isc_block(ipos); 
+    pp->pos = isc_block(ipos); 
 
     src = pp->buf = xmalloc (is->method->filecat[pp->cat].bsize);
 
-    pp->pos = 0;    
+    pp->next = 0;
     pp->size = 0;
     pp->offset = 0;
     pp->is = is;
     pp->decodeClientData = (*is->method->code_start)(ISAMC_DECODE);
     pp->deleteFlag = 0;
+    pp->numKeys = 0;
+
+    if (pp->pos)
+    {
+        src = pp->buf;
+        isc_read_block (is, pp->cat, pp->pos, src);
+        memcpy (&pp->next, src, sizeof(pp->next));
+        src += sizeof(pp->next);
+        memcpy (&pp->size, src, sizeof(pp->size));
+        src += sizeof(pp->size);
+        memcpy (&pp->numKeys, src, sizeof(pp->numKeys));
+        src += sizeof(pp->numKeys);
+        assert (pp->next != pp->pos);
+        pp->offset = src - pp->buf; 
+        assert (pp->offset == ISAMC_BLOCK_OFFSET_1);
+        if (is->method->debug > 2)
+            logf (LOG_LOG, "isc: read_block size=%d %d %d",
+                 pp->size, pp->cat, pp->pos);
+    }
     return pp;
 }
 
 /* returns non-zero if item could be read; 0 otherwise */
-int isc_read_key (ISAMC_PP pp, void *buf)
+int isc_pp_read (ISAMC_PP pp, void *buf)
 {
     return isc_read_item (pp, (char **) &buf);
 }
@@ -268,11 +364,15 @@ int isc_read_item (ISAMC_PP pp, char **dst)
         memcpy (&pp->size, src, sizeof(pp->size));
         src += sizeof(pp->size);
         /* assume block is non-empty */
+        assert (src - pp->buf == ISAMC_BLOCK_OFFSET_N);
         assert (pp->next != pp->pos);
         if (pp->deleteFlag)
             isc_release_block (is, pp->cat, pp->pos);
         (*is->method->code_item)(ISAMC_DECODE, pp->decodeClientData, dst, &src);
         pp->offset = src - pp->buf; 
+        if (is->method->debug > 2)
+            logf (LOG_LOG, "isc: read_block size=%d %d %d",
+                 pp->size, pp->cat, pp->pos);
         return 2;
     }
     (*is->method->code_item)(ISAMC_DECODE, pp->decodeClientData, dst, &src);
@@ -280,8 +380,8 @@ int isc_read_item (ISAMC_PP pp, char **dst)
     return 1;
 }
 
-int isc_numkeys (ISAMC_PP pp)
+int isc_pp_num (ISAMC_PP pp)
 {
-    return 1;
+    return pp->numKeys;
 }