From c3017e7b4a1829f3e8bc4f26f5b05b31836120e0 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Mon, 25 Feb 2019 14:52:43 +0000
Subject: [PATCH] Update comments on the fossildelta extension.  No changes to
 code.

FossilOrigin-Name: 9da4fb59b28686630d63a79988b458726332cf06cc0e6e84d7c0a7600f5fcab0
---
 ext/misc/fossildelta.c | 40 +++++++++++++++++++++++++++++++++++-----
 manifest               | 12 ++++++------
 manifest.uuid          |  2 +-
 3 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/ext/misc/fossildelta.c b/ext/misc/fossildelta.c
index 7a9c5c1d72..b58d358b55 100644
--- a/ext/misc/fossildelta.c
+++ b/ext/misc/fossildelta.c
@@ -600,7 +600,7 @@ static int delta_apply(
 }
 
 /*
-** SQL functions:  fossildelta_create(X,Y)
+** SQL functions:  delta_create(X,Y)
 **
 ** Return a delta for carrying X into Y.
 */
@@ -635,7 +635,7 @@ static void deltaCreateFunc(
 }
 
 /*
-** SQL functions:  fossildelta_apply(X,D)
+** SQL functions:  delta_apply(X,D)
 **
 ** Return the result of applying delta D to input X.
 */
@@ -678,7 +678,7 @@ static void deltaApplyFunc(
 
 
 /*
-** SQL functions:  fossildelta_output_size(D)
+** SQL functions:  delta_output_size(D)
 **
 ** Return the size of the output that results from applying delta D.
 */
@@ -704,8 +704,38 @@ static void deltaOutputSizeFunc(
   }
 }
 
-/* The deltaparse(DELTA) table-valued function parses the DELTA in
-** its input and returns a table that describes that delta.
+/*****************************************************************************
+** Table-valued SQL function:   delta_parse(DELTA)
+**
+** Schema:
+**
+**     CREATE TABLE delta_parse(
+**       op TEXT,
+**       a1 INT,
+**       a2 ANY,
+**       delta HIDDEN BLOB
+**     );
+**
+** Given an input DELTA, this function parses the delta and returns
+** rows for each entry in the delta.  The op column has one of the
+** values SIZE, COPY, INSERT, CHECKSUM, ERROR.
+**
+** Assuming no errors, the first row has op='SIZE'.  a1 is the size of
+** the output in bytes and a2 is NULL.
+**
+** After the initial SIZE row, there are zero or more 'COPY' and/or 'INSERT'
+** rows.  A COPY row means content is copied from the source into the
+** output.  Column a1 is the number of bytes to copy and a2 is the offset
+** into source from which to begin copying.  An INSERT row means to
+** insert text into the output stream.  Column a1 is the number of bytes
+** to insert and column is a BLOB that contains the text to be inserted.
+**
+** The last row of a well-formed delta will have an op value of 'CHECKSUM'.
+** The a1 column will be the value of the checksum and a2 will be NULL.
+**
+** If the input delta is not well-formed, then a row with an op value
+** of 'ERROR' is returned.  The a1 value of the ERROR row is the offset
+** into the delta where the error was encountered and a2 is NULL.
 */
 typedef struct deltaparsevtab_vtab deltaparsevtab_vtab;
 typedef struct deltaparsevtab_cursor deltaparsevtab_cursor;
diff --git a/manifest b/manifest
index 7db9d11be5..a725656c76 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\stypo\sin\sthe\sdocumentation\sfor\ssqlite3_total_changes().
-D 2019-02-25T14:16:19.183
+C Update\scomments\son\sthe\sfossildelta\sextension.\s\sNo\schanges\sto\scode.
+D 2019-02-25T14:52:43.832
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in 178d8eb6840771149cee40b322d1b3be30d330198c522c903c1b66fb5a1bfca4
@@ -286,7 +286,7 @@ F ext/misc/dbdump.c baf6e37447c9d6968417b1cd34cbedb0b0ab3f91b5329501d8a8d5be3287
 F ext/misc/eval.c 4b4757592d00fd32e44c7a067e6a0e4839c81a4d57abc4131ee7806d1be3104e
 F ext/misc/explain.c d5c12962d79913ef774b297006872af1fccda388f61a11d37758f9179a09551f
 F ext/misc/fileio.c 592d6531d8413d81b25f5a47a45d7e310e455d33e03a64c6ae85724c6524a5d5
-F ext/misc/fossildelta.c 31b64084789228ac0d1113e5e39dc79c2ae16dd131d5c988ad9550ae1b9bc4b4
+F ext/misc/fossildelta.c 3cc9a9b2f39889b43cd176c19f286bc7dd652f4c202c202d008481252d820316
 F ext/misc/fuzzer.c 9e79c337faffdd4c5fe4485467537438359b43e0858a40038d4300b894ff553f
 F ext/misc/ieee754.c f190d0cc5182529acb15babd177781be1ac1718c
 F ext/misc/json1.c 8af4672f43634257dbcfdb4515b4070325463d67c6968b4be1bd414de28d4d58
@@ -1805,7 +1805,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 84162af521f29df8a186163fbdef9856e1aa8aba78e74d7df0ba2cc83bb86240
-R a2b016f8e876d7afed026960b97cfb9a
+P 8474c1560e0c3a28c6a7ed360202a8e7caae3c8259f60bbfa6d2948ab7876f51
+R b6b94692df1ff68d1775b0307c4b76d3
 U drh
-Z 55e24971867c6a920f00e5ee1b3ee79b
+Z 398771f938c8db2543123478ba7fdec9
diff --git a/manifest.uuid b/manifest.uuid
index 3940420865..3326c630fa 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-8474c1560e0c3a28c6a7ed360202a8e7caae3c8259f60bbfa6d2948ab7876f51
\ No newline at end of file
+9da4fb59b28686630d63a79988b458726332cf06cc0e6e84d7c0a7600f5fcab0
\ No newline at end of file