File 1072-kernel-Correct-disk_log-s-calculation-of-no_items.patch of Package erlang
From 2b40082715f419988537bf430ad0045ba8a71839 Mon Sep 17 00:00:00 2001
From: Hans Bolinder <hasse@erlang.org>
Date: Wed, 19 Aug 2020 08:15:01 +0200
Subject: [PATCH] kernel: Correct disk_log's calculation of no_items
disk_log:truncate/1 did not take the header into account when
calculating number of items.
The docs are updated to state that disk_log:truncate/1 can be used for
logs on the external format.
---
lib/kernel/doc/src/disk_log.xml | 9 ++++---
lib/kernel/src/disk_log.erl | 2 +-
lib/kernel/test/disk_log_SUITE.erl | 41 +++++++++++++++++++++++++++---
3 files changed, 45 insertions(+), 7 deletions(-)
diff --git a/lib/kernel/doc/src/disk_log.xml b/lib/kernel/doc/src/disk_log.xml
index e033a3baad..5a33796005 100644
--- a/lib/kernel/doc/src/disk_log.xml
+++ b/lib/kernel/doc/src/disk_log.xml
@@ -958,7 +958,7 @@
written first on the log file. If the log is a wrap
log, the item <c><anno>Head</anno></c> is written first in each new file.
<c><anno>Head</anno></c> is to be a term if the format is
- <c>internal</c>, otherwise a sequence of bytes.
+ <c>internal</c>, otherwise an <c>iodata()</c>.
Defaults to <c>none</c>, which means that
no header is written first on the file.
</p>
@@ -970,7 +970,7 @@
The call <c>M:F(A)</c> is assumed to return <c>{ok, Head}</c>.
The item <c>Head</c> is written first in each file.
<c>Head</c> is to be a term if the format is
- <c>internal</c>, otherwise a sequence of bytes.
+ <c>internal</c>, otherwise an <c>iodata()</c>.
</p>
</item>
<tag><c>{mode, <anno>Mode</anno>}</c></tag>
@@ -1125,7 +1125,10 @@
The header argument is used only once. Next time a wrap log file
is opened, the header given to <c>open/1</c> is used.
</p>
- <p><c>truncate/1,2</c> are used for internally
+ <p><c>truncate/1</c> is used for both internally and externally
+ formatted logs.
+ </p>
+ <p><c>truncate/2</c> is used for internally
formatted logs, and <c>btruncate/2</c> for externally formatted
logs.
</p>
diff --git a/lib/kernel/src/disk_log.erl b/lib/kernel/src/disk_log.erl
index 05ea6a648f..3e1d0a2224 100644
--- a/lib/kernel/src/disk_log.erl
+++ b/lib/kernel/src/disk_log.erl
@@ -763,7 +763,7 @@ handle({From, {truncate, Head, F, A}}=Message, S) ->
ok ->
erase(is_full),
notify_owners({truncated, S#state.cnt}),
- N = if Head =:= none -> 0; true -> 1 end,
+ N = if H =:= none -> 0; true -> 1 end,
reply(From, ok, (state_ok(S))#state{cnt = N});
Error ->
do_exit(S, From, Error, ?failure(Error, F, A))
diff --git a/lib/kernel/test/disk_log_SUITE.erl b/lib/kernel/test/disk_log_SUITE.erl
index dc72c304cc..99711bcf75 100644
--- a/lib/kernel/test/disk_log_SUITE.erl
+++ b/lib/kernel/test/disk_log_SUITE.erl
@@ -91,7 +91,7 @@
evil/1,
- otp_6278/1, otp_10131/1]).
+ otp_6278/1, otp_10131/1, otp_16768/1]).
-export([head_fun/1, hf/0, lserv/1,
measure/0, init_m/1, xx/0, head_exit/0, slow_header/1]).
@@ -123,7 +123,7 @@
[halt_int, wrap_int, halt_ext, wrap_ext, read_mode, head,
notif, new_idx_vsn, reopen, block, unblock, open, close,
error, chunk, truncate, many_users, info, change_size,
- change_attribute, distribution, evil, otp_6278, otp_10131]).
+ change_attribute, distribution, evil, otp_6278, otp_10131, otp_16768]).
%% These test cases should be skipped if the VxWorks card is
%% configured without NFS cache.
@@ -149,7 +149,7 @@ all() ->
{group, open}, {group, close}, {group, error}, chunk,
truncate, many_users, {group, info},
{group, change_size}, change_attribute,
- {group, distribution}, evil, otp_6278, otp_10131].
+ {group, distribution}, evil, otp_6278, otp_10131, otp_16768].
groups() ->
[{halt_int, [], [halt_int_inf, {group, halt_int_sz}]},
@@ -4820,6 +4820,41 @@ otp_10131(Conf) when is_list(Conf) ->
ok = disk_log:close(Log),
ok.
+%% OTP-16768. Bad number of items with truncate/1. ERL-1312, ERL-1313.
+otp_16768(Conf) when is_list(Conf) ->
+ Dir = ?privdir(Conf),
+ Log = otp_16768,
+ File = filename:join(Dir, Log),
+ Header = <<"123456789\n">>,
+ head_count(Log, File, Header, external, 25),
+ head_count(Log, File, none, external, 20),
+ head_count(Log, File, Header, internal, 30),
+ head_count(Log, File, none, internal, 20),
+ ok.
+
+head_count(Log, File, Header, Format, Expected) ->
+ del(File, 10),
+ Content = <<"1234567890123456789\n">>,
+ HeaderSize = case Header of
+ none -> 0;
+ _ -> byte_size(Header)
+ end,
+ %% 5 files for the external format, more for the internal format
+ MaxSizePerFile = HeaderSize + (5 * byte_size(Content)) - 1,
+ {ok, Log} = disk_log:open([{file, File},
+ {name, Log},
+ {format, Format},
+ {head, Header},
+ {size, {MaxSizePerFile, 999}},
+ {type, wrap}
+ ]),
+ ok = disk_log:truncate(Log),
+ lists:foreach(fun(_I) -> disk_log:blog(Log, Content) end,
+ lists:seq(1, 20)),
+ DiskLogInfo = disk_log:info(Log),
+ Expected = proplists:get_value(no_items, DiskLogInfo),
+ ok = disk_log:close(Log).
+
mark(FileName, What) ->
{ok,Fd} = file:open(FileName, [raw, binary, read, write]),
{ok,_} = file:position(Fd, 4),
--
2.26.2
