From: drh <drh@noemail.net>
Date: Tue, 27 Mar 2007 14:05:22 +0000 (+0000)
Subject: Fix off-by-one errors in the header comments of btree.c.  Ticket #2272. (CVS 3726)
X-Git-Tag: version-3.6.10~2444
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a4124a06ccecdde264ca7b4f01dff0c2e2fd7be9;p=thirdparty%2Fsqlite.git

Fix off-by-one errors in the header comments of btree.c.  Ticket #2272. (CVS 3726)

FossilOrigin-Name: a70ea7202d8ffb0321ff8f2e5036731bb1742eb8
---

diff --git a/manifest b/manifest
index 8c9bd7024b..62f744d3c6 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C More\sstrict\saliasing\sfixes.\s\sThe\ssingle\ssource\sfile\slibrary\snow\sruns\nsuccessfully\swith\s-fstrict-alias.\s(CVS\s3725)
-D 2007-03-27T13:36:37
+C Fix\soff-by-one\serrors\sin\sthe\sheader\scomments\sof\sbtree.c.\s\sTicket\s#2272.\s(CVS\s3726)
+D 2007-03-27T14:05:23
 F Makefile.in 1fe3d0b46e40fd684e1e61f8e8056cefed16de9f
 F Makefile.linux-gcc 2d8574d1ba75f129aba2019f0b959db380a90935
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -58,7 +58,7 @@ F src/alter.c 2c79ec40f65e33deaf90ca493422c74586e481a3
 F src/analyze.c 7d2b7ab9a9c2fd6e55700f69064dfdd3e36d7a8a
 F src/attach.c 9b5a9c50fb92883e3404353b225674142da826cd
 F src/auth.c 902f4722661c796b97f007d9606bd7529c02597f
-F src/btree.c 0659070eb438bae32cec8afebe6d8d390024d952
+F src/btree.c 27e62fc50dba2ac0b4210402804ac12321ad8e59
 F src/btree.h 066444ee25bd6e6accb997bfd2cf5ace14dbcd00
 F src/build.c d178bd7c8117f5f47694da9a0d5f336e85528180
 F src/callback.c 31d22b4919c7645cbcbb1591ce2453e8c677c558
@@ -442,7 +442,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P 1dd9d0775a8199047de30218af71a31c731fedb1
-R 788fdfcff1fda81d98ec4386ff9fe62b
+P c8a8a189a82500aab501e9949f5b197c0b80b3a9
+R 4093f5fe8a47b839b227af98195abbcf
 U drh
-Z a721db4fcd13afdccda21f5563fa1a8b
+Z 6e347bdb933f7ff4141334d59e940f6d
diff --git a/manifest.uuid b/manifest.uuid
index bf55336c86..e501b0d76c 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-c8a8a189a82500aab501e9949f5b197c0b80b3a9
\ No newline at end of file
+a70ea7202d8ffb0321ff8f2e5036731bb1742eb8
\ No newline at end of file
diff --git a/src/btree.c b/src/btree.c
index 9b8879f989..9c9e8838fd 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btree.c,v 1.342 2007/03/26 22:05:01 drh Exp $
+** $Id: btree.c,v 1.343 2007/03/27 14:05:23 drh Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** For a detailed discussion of BTrees, refer to
@@ -22,13 +22,13 @@
 ** entries and N+1 pointers to subpages.
 **
 **   ----------------------------------------------------------------
-**   |  Ptr(0) | Key(0) | Ptr(1) | Key(1) | ... | Key(N) | Ptr(N+1) |
+**   |  Ptr(0) | Key(0) | Ptr(1) | Key(1) | ... | Key(N-1) | Ptr(N) |
 **   ----------------------------------------------------------------
 **
 ** All of the keys on the page that Ptr(0) points to have values less
 ** than Key(0).  All of the keys on page Ptr(1) and its subpages have
 ** values greater than Key(0) and less than Key(1).  All of the keys
-** on Ptr(N+1) and its subpages have values greater than Key(N).  And
+** on Ptr(N) and its subpages have values greater than Key(N-1).  And
 ** so forth.
 **
 ** Finding a particular key requires reading O(log(M)) pages from the 
@@ -41,7 +41,7 @@
 ** page.  If the payload is larger than the preset amount then surplus
 ** bytes are stored on overflow pages.  The payload for an entry
 ** and the preceding pointer are combined to form a "Cell".  Each 
-** page has a small header which contains the Ptr(N+1) pointer and other
+** page has a small header which contains the Ptr(N) pointer and other
 ** information such as the size of key and data.
 **
 ** FORMAT DETAILS
@@ -123,7 +123,7 @@
 **      3       2      number of cells on this page
 **      5       2      first byte of the cell content area
 **      7       1      number of fragmented free bytes
-**      8       4      Right child (the Ptr(N+1) value).  Omitted on leaves.
+**      8       4      Right child (the Ptr(N) value).  Omitted on leaves.
 **
 ** The flags define the format of this btree page.  The leaf flag means that
 ** this page has no children.  The zerodata flag means that this page carries