- Implement file reading and writing: l2g_read, l2g_write

- Make the following more efficient: l2g_copy
- Bug fixes: l2g_clear, l2g_delete

src/server/local-to-global.c

@@ -18,6 +18,9 @@
 
 #include "kom-types.h"
 #include "local-to-global.h"
+#include "log.h"
+#include "ram-parse.h"
+#include "ram-output.h"
 
 
 /* ================================================================ */
@@ -56,6 +59,30 @@ add_block(Local_to_global *l2g)
 }
 
 
+/*
+ * Delete a block from the Local_to_global L2G.  The pointer BINFO
+ * points at the block, which is supposed to be empty.
+ */
+
+static void
+delete_block(Local_to_global *l2g, 
+	     L2g_block_info  *binfo)
+{
+    /* Remove the blocks from the Block Info */
+    if (binfo->key_block != NULL)
+	free(binfo->key_block);
+    free(binfo->value_block);
+
+    /* Compact the remaining blocks. */
+    while (++binfo < l2g->blocks + l2g->num_blocks)
+	*(binfo - 1) = *binfo;
+    l2g->num_blocks--;
+    l2g->blocks = (L2g_block_info *) 
+	realloc(l2g->blocks, 
+		l2g->num_blocks * sizeof(L2g_block_info));
+}
+
+
 /*
  * Make a sparse block from a dense one.
  */
@@ -144,9 +171,6 @@ void
 l2g_destruct(Local_to_global *l2g)
 {
     l2g_clear(l2g);
-    
-    /* Free the block pointers */
-    free(l2g->blocks);
 }
 
 
@@ -183,10 +207,12 @@ l2g_clear(Local_to_global *l2g)
 	binfo++;
     }
 
-    /* Free the block pointers except the first one. */
+    /* Free the block pointers. */
     l2g->num_blocks = 0;
-    free(l2g->blocks);
-    l2g->blocks = NULL;
+    if (l2g->blocks != NULL) {
+	free(l2g->blocks);
+	l2g->blocks = NULL;
+    }
 }
 
 
@@ -258,8 +284,8 @@ l2g_append(Local_to_global *l2g,
 	       && lno - binfo->start >= L2G_BLOCKSIZE){
 	/* 
 	 * If the last block is dense, and LNO is outside the block,
-	 * see if we should convert it to a sparse block or if we should 
-	 * allocate a new one.
+	 * check if we should convert it to a sparse block or if we 
+	 * should allocate a new one.
 	 */
 	if ((L2G_BLOCKSIZE - binfo->first_free) 
 	    + binfo->zeroes > L2G_BLOCKSIZE / 2) {
@@ -325,6 +351,14 @@ l2g_delete(Local_to_global *l2g, Local_text_no lno)
 	    }
 	}
     }
+
+    /* Delete the block if it is empty. */
+    /* NOTE, FIXME: Check what this does to iterators, and maybe */
+    /*              find some other way.  Perhaps we could set */
+    /*              next_free to -1 or something and then remove */
+    /*              the blocks only when compact() is called. */
+    if (binfo->zeroes == L2G_BLOCKSIZE)
+	delete_block(l2g, binfo);
 }
 
 
@@ -347,14 +381,12 @@ l2g_lookup(Local_to_global *l2g, Local_text_no lno)
 	/* A dense block */
 	if (binfo->start <= lno && lno < binfo->start + L2G_BLOCKSIZE)
 	    return binfo->value_block[lno - binfo->start];
-	return 0;
     } else {
 	/* FIXME: Binary search */
 	for (i = 0; i < binfo->first_free && binfo->key_block[i] <= lno; ++i) {
 	    if (binfo->key_block[i] == lno)
 		return binfo->value_block[i];
 	}
-	return 0;
     }
 
     return 0;
@@ -437,8 +469,8 @@ l2g_compact(Local_to_global *l2g)
 
     l2g_init(&dummy);
     l2g_copy(l2g, &dummy);
-    l2g_copy(&dummy, l2g);
-    l2g_destruct(&dummy);
+    l2g_destruct(l2g);
+    *l2g = dummy;
 }
 
 
@@ -483,20 +515,74 @@ l2g_dump(Local_to_global *l2g, FILE *file)
 
 
 /*
- * 
+ * Read a Local to global structure from the file FILE.
  */
 
 void
-l2g_read(Local_to_global *l2g, FILE *file)
+l2g_read(Local_to_global *l2g, FILE *fp)
 {
+    int            c;
+    Local_text_no  lno;
+    Text_no        tno;
+
+    /* Read past the start marker */
+    fskipwhite(fp);
+    if ( (c = getc(fp)) == EOF || c != '[') {
+	log("l2g_read() failed at pos %lu.\n", (unsigned long) ftell(fp));
+	return;
+    }
+
+    /* Read pairs of numbers until the EOL (end-of-l2g :-) ) marker is read. */
+    while (1) {
+	fskipwhite(fp);
+	if ((c = getc(fp)) == ']')
+	    break;
+	else
+	    ungetc(c, fp);
+
+	lno = (Local_text_no) fparse_long(fp);
+	tno = (Text_no)       fparse_long(fp);
+	l2g_append(l2g, lno, tno);
+    }
 }
 
 
 /*
- * 
+ * Print the structure to the file FILE.
  */
 
 void
-l2g_print(Local_to_global *l2g, FILE *file)
+l2g_write(Local_to_global *l2g, FILE *fp)
 {
+    L2g_block_info  * binfo;
+    int               i, j;
+
+    putc('[', fp);
+
+    binfo = l2g->blocks;
+    for (i = 0; i < l2g->num_blocks; ++i) {
+	if (binfo->key_block == NULL) {
+	    /* Dense block */
+
+	    for (j = 0; j < binfo->first_free; ++j) {
+		if (binfo->value_block[j] != 0) {
+		    foutput_ulong((unsigned long) (binfo->start + j), fp);
+		    foutput_ulong((unsigned long) (binfo->value_block[j]), fp);
+		}
+	    }
+	} else {
+	    /* Sparse block */
+
+	    for (j = 0; j < binfo->first_free; ++j) {
+		if (binfo->value_block[j] != 0) {
+		    foutput_ulong((unsigned long) (binfo->key_block[j]), fp);
+		    foutput_ulong((unsigned long) (binfo->value_block[j]), fp);
+		}
+	    }
+	}
+
+	binfo++;
+    }
+
+    fputs(" ]", fp);
 }