Krzysztof Kowalczyk blog

SumatraPDF 1.0 released

2009-11-19T05:46:59Z

I’ve released 1.0 version of Sumatra. Compared to 0.9.4 it has bunch of bug fixes and small improvements. Each of them is too small to single out, but together they improve Sumatra quite a bit.

This version gets the 1.0 version and officially is out of beta because, well, it’s time.

This version has received great many improvements from Simon Bünzli (zeniko) and some more TeXSync support fixes from William Blum so they deserve much credit for this release.

It’s available here

Web server in C#

2009-11-04T05:50:13Z

If you need a simple web server for .NET, this is a solid piece of software.

I’ve needed an internal web server for my C# application and re-using someone else’s code certainly beats writing it from scratch.

It’s not spelled out on the web page, but it comes in two flavors:

lite, with only http serving core. When you download the code, look for it in branches directory
standard, which also includes things like templating engine

When I used added it to my project, I didn’t know about the lite version, so I added the files manually to the project and removed files I didn’t need manually. If I were starting from scratch, I would just use lite version.

So far I’m happy with the code – it does exactly what it advertises, saved me a bunch of time I didn’t spend writing it myself.

It uses Apache 2.0 license so can be used in commercial software as well.

15minutes for mac updated

2009-11-01T07:55:47Z

I’ve made two small improvement to my 15minutes app for mac that is meant as a simple productivity tool that helps to focus on doing things.

Improvements:

time display is bigger
it now has non-awful icon

I also came to a realization that it should really be more unobtrusive app that lives in the menu bar and has even more minimal UI. However, at present I don’t have the time to do that. 15minutes has been something that I wanted to get done as quickly as possible. It would be ironic if my productivity dropped due to spending a lot of time working on productivity-enhancing application.

It's the little things

2009-10-22T06:56:54Z

I just installed Visual Studio 2010 Beta 2 and tried it on Sumatra. Unlike Beta 1 it properly converted project file from vs 2008. After playing with it for a few minutes it looks like a worthy upgrade to 2008 which is why it stings even more when a useful functionality is missing.

Lenovo’s thinkpads have nice feature of combined TrackPoint and UltraNav that allows easy scrolling in many apps (I think they generate scroll-wheel events). Unfortunately the new, rewritten editor in 2010 doesn’t seem to support this kind of scrolling and it’s one of those features that I use very often and became so dependent on it that it’s hard to use an application that doesn’t support it.

Here’s me hoping that it was just lack of time in beta 2 cycle and it’ll be supported in final release, since it would be really painful to use the editor on a ThinkPad laptop without it.

Unicode problem with firstof in appengine/Django

2009-10-22T00:30:33Z

I spent a couple of hours tracking and fixing this problem.

A user reported an error in my fofou forum software for appengine: a forum that had german text in tagline couldn’t be edited. All appengine told me was this mostly useless error message: “UnicodeEncodeError: ‘ascii’ codec can’t encode character u’\xdc’ in position 0: ordinal not in range(128)” coming from template.render.

By trial and error I narrowed down the culprit to this part of the template: ”{% firstof forum.tagline “Tagline.” %}”. forum.tagline comes from a datastore, so it’s unicode. Error message tells me that (for whatever reason) template rendering is trying to convert that unicode string to ascii using ascii codec and (rightfully) failing.

Using just ”{{ forum.tagline }}” works so it seems that the problem is limited to firstof statement. The only solution I found was doing the firstof logic in python code and removing firstof from template.

The bottom line is that firstof is useless if you ever hope to use it with non-ascii strings.

I’ve opened a bug for this.

Google Wave as replacement of EverNote

2009-10-21T01:50:23Z

EverNote was the best note taking application I found so far. It’s free and it works on Mac and Windows. Unfortunately the best does not mean it’s good.

While EverNote packs a lot of advanced features, like recognizing text in images, the basic functionality is riddled with bugs and unpolished experiences that I encounter on a daily basis. A real shame for software that has been in the market for so long.

I’ve been using Google Wave for a few days and it looks like it might be a good note taker. It’s inherently cross-platform by virtue of running in the browser, it has a pleasent user interface and all the basic text formating functionality that I need.

It does have its share of bugs, but I’m more forgiving given that it’s a preview release and Google is very clear it’s not a finished product.

We need Visual Ack

2009-09-18T16:51:35Z

ack is a nifty improvement over grep written in perl. However, it’s a command-line app and those days dumping results into terminal window isn’t very inspired.

What would be nice is a Visual Ack, which would present the results in an easier to digest way i.e. an app with native UI with results in a new window, nicely presented.

That’s my lazy web request for today.

Sumatra 0.9.4 release

2009-07-20T07:07:21Z

I’ve released a new version of SumatraPDF, my PDF reader for Windows.

It’s been 9 months since previous release.

This version mostly improves PDF compatibility (more PDFs can be opened and rendered), fixes lots of bugs reported in the bug tracker and adds UI polish.

Many improvements in this version were contributed by Simon Bünzli and William Blum.

The most visible changes are:

improved PDF compatibility (more types of documents can be rendered)
added settings dialog (contributed by Simon Bünzli)
improvements in handling unicode
changed default view from single page to continuous
SyncTex improvements (contributed by William Blum)
add option to not remember opened files
a new icon for documents association (contributed by George Georgiou)
lots of bugfixes and UI polish

15minutes for mac now available

2009-06-23T02:37:12Z

My simple productivity application 15minutes used to only run on Windows. I just finished writing Mac OS X version so a blog post announcing it seems appropriate.

Cocoa and Objective-C reference

2009-06-15T03:00:14Z

I’ve started programming in Cocoa again. I’m only an advanced beginner in that framework so I often have to look up how to achieve even simple things. To make programming a little bit faster, I started working on a Cocoa quick reference.

It lists the most frequently used methods and classes in Cocoa, with links to official Apple docs.

On a side note, I think that existing quick reference guides on the web aren’t very good. I have a few ideas on how they could be improved and hope to use those ideas in my Cocoa reference.

Shared http caching

2009-06-13T21:27:24Z

In March I wrote about an idea for tagging links with their sha1 checksum for better caching in web browser. Now I’m not alone.

Network drives, .net, security and virtualbox

2009-06-05T06:28:28Z

I have Windows 7 installed on my MacBook under VirtualBox. To keep things simple, I keep my code on mac side, sharing the directory with Windows side.

Tip #1: VirtualBox 2.2.4 has weak implementation of shared folders. For example, Visual Studio 2008 sees the files on shared drive as write-protected (even though other applications don’t). Visual Studio 2010 doesn’t have this problem, but it can’t finish compilation, complaining it cannot write some intermediary build files to a shared folder. Also, trying to mark shared folder as trustworthy for .NET doesn’t seem to work (see below).

Solution: use Mac’s built-in file sharing instead and shared things out using built-in samba (smb) sharing in System Preferences/Sharing.

Another problem is that .NET by default doesn’t trust code on network drives and Visual Studio will tell you that “The Project Location is Not Trusted” if you open a project from a network drive. The magic incantation to make a given shared folder (in my case it’s drive z:) trusted is:

caspol -q -machine -addgroup 1.2 -url file://z:/* FullTrust

This command has to be executed as Administrator.

One way to have caspol.exe available in the PATH is to start Visual Studio cmd-line (shortcut is installed in Start menu).

Setting unicode rtf text in rich edit control

2009-04-15T06:36:41Z

Despite being around for thousands of years, win32 API is poorly documented in many areas.

Today I spent an hour battling a baffling problem with rich edit control.

I was setting rtf-formatted text using WM_SETTEXT message.

In non-unicode build, where text was ansi, it worked and the text showed up nicely formatted.

In unicode build, however, the text wasn’t parsed as rtf and showed verbatim.

An hour of trying various ways to make it work ended with me finding a working work-around: using EM_SETTEXTEX and utf-8 encoded text with CP_UTF8 code-page. I’m using WTL so the code ended up being:

#ifdef UNICODE
		// Don't know why I have to do this, but SetWindowText() with unicode
		// doesn't work (rtf codes are not being recognized)
		const char *sUtf = WstrToUtf8(s);
		m_statusMsgEdit.SetTextEx((LPCTSTR)sUtf, ST_DEFAULT, CP_UTF8);
#else
		m_statusMsgEdit.SetWindowText(s);
#endif

MSDN claims I could have used code-page 1200 for unicode text, but that didn’t work either.

It’s quite possible I’ve botched something somewhere in my code and this work-around isn’t needed but I can hardly think of anything. If you ever run into problem like this, the above is one thing to try.

Accessing Mac file shares from Windows 7

2009-04-11T22:40:54Z

Windows 7 beta 7000 can’t access files shared from Mac through built-in samba file sharing out of the box. It’s rather infuriating, because XP has no such problem and the error message given by windows when you try to navigate to a folder shared from mac is cryptic and not helpful at all. Turns out the culprit is purely how Windows 7 security is configured by default. Good news is it can be fixed via configuration tweaks as described here.

In case this post goes away, here’s what it says:

Windows 7 will not work with Mac OS X Windows file sharing support by default. If you attempt to access a folder shared from Mac OS X, Vista will display a logon error repeatedly. The problem is that Vista, by default, will only use NTLMv2 for authentication, which is not supported by Mac OS X’s Windows Sharing service. The other problem is the Minimum Session Security for NTVLM SSP based Clients.
To get around this:

1. In Vista, open the Control Panel
2. Switch to “Classic” view
3. Double-click Administration Tools
4. Double-click Local Security Policy
5. Or Secpol.msc
6. Expand “Local Policies” and select “Security Options”
7. Alternate : Type secpol.msc to get editor up then
8. Locate “Network Security: LAN Manager Authentication Level” in the list and double-click it.
9. Change the setting from “Send NTMLv2 response only” to “Send LM & NTLM – use NTLMv2 session if negotiated”
10. Network Security: Minimum session security for NTLM SSP Based (including secure RPC) Clients
11. Change the setting from “require 128 bit” to unchecked (No Minimum)
12. Click OK

the real difference between vista and windows 7 procedure is 10 and 11

It’s rather evil for Microsoft to choose defaults that make file sharing not interoperable with latest Mac OS X. It’s not like they didn’t test it so it must have been a conscious decision to screw with Mac users.

15minutes - a simple productivity tool

2009-04-09T05:48:04Z

15minutes is a simple productivity tool I wrote.

One of productivity techniques is time boxing. Pomodoro technique is a similar idea.

Procrastination is avoiding work. To avoid procrastination you just have to start working.

One reason we avoid work is because the tasks seem big and overwhelming. Time boxing is a mental trick – instead of thinking about doing the whole task, we focus about working on a task for a fixed, short period of time.

To implement time boxing you need a timer which will alert you about the end of time boxing period.

Any timer will do – a physical timer, iPhone’s built-in clock etc.

I wrote a small application to do it, since most of my work is done on a computer. 15minutes is that application.

Recent mupdf work

2009-04-06T05:21:28Z

I’ve been working a little bit on Sumatra and mupdf recently. The result of which are 9 patches submitted to mupdf upstream.

Valgrind on mac

2009-03-28T04:04:36Z

As of Mar 27 2009 Valgrind doesn’t officially support mac but a port that is good enough is in progress. You can learn more and monitor the progress by reading Nicholas Nethercote’s blog (main person working on Valgrind mac port).

This post is a summary of how I built Valgrind on Mac (OS X 10.5.6).

Since this involves compiling, you probably need developer tools. I have both XCode and a healthy does of MacPorts dev packages installed. I’m not sure how much you need, but I’m guessing at least gcc, make, autotools.

svn co svn://svn.valgrind.org/valgrind/trunk valgrind
cd valgrind
./autogen.sh
./configure
make
sudo make install

So far I’ve only tried Valgrind on mupdf and it worked, so this is very promising. Valgrind is invaluable tool for C/C++ memory leak detection, detecting memory mismanagement issues and profiling the code.

An unfortunate deficiency is lack of a GUI for inspecting callgrind results (i.e. kcachegrind equivalent on mac). Maybe the cheapest way to get that would be to convert callgrind results to shark format so that shark tools can be used. Should be possible – I believe WebKit’s JavaScript implementation saves profiling results in shark format, so there is code that could be used as a template for that.

Unladden-swallow - making Python faster

2009-03-28T03:02:47Z

When I’m right, I’m right. About a year ago I said that Google should sponsor faster Python VM. And that’s exactly what they did by having 2 full time engineers working on unladden-swallow, a project to make Python much faster, with full intention to get all their improvements into mainline Python.

The project looks very promising.

It also shows that small teams can do great things. 2 people team is as small as it gets and if they manage to achieve their goal, they’ll make a big difference in many programmer’s lives.

Interesting mac source code

2009-03-16T03:06:44Z

Interesting mac sourcecode:

Understudy – GPL, front row plugin that adds support for Hulu, Netflix, YouTube.

HTTP Client – BSD, UI for sending HTTP requests and inspecting HTTP requests/responses

MacShark, network sniffer, nmap, dig, whois etc., New BSD

Eavesdrop, GPLv2, network sniffer

hexfiend, BSD, hex editor

iLife 08-like source list, New BSD, ui widget

AppHider – moves apps from doc to menubar

RoaringDiff – graphical diff

ReaderNotifier – shows Google Reader status in menu bar

Quick Search Box – from Google

MenuMeters – GPL, shows stuff in menu bar

Http upload sample

Silverlight info

2009-03-14T23:16:43Z

http://blogs.msdn.com/jstegman/archive/2008/04/21/dynamic-image-generation-in-silverlight.aspx has code to dynamically generate bitmaps in Silverlight.

FJCore – Jpeg decoder and encoder + resizing, in just C#

Interesting win32 source code

2009-03-14T23:14:12Z

Interesting win32 source code:

puttycyg – cygwin terminal, putty modified to also be a cygwin terminal, MIT
putty, MIT, putty Tray, enhancements to Putty
qemacs, LGPL
WTL
WDL – Justin Frankel’s library for win32 & win32 emulation for mac, BSD-like
TaskSwitchXP – BSD-like (?)
stb-img, GPL with parts in public domain (zlib, png, jpeg decompressors)
qsniffer, GPLv2, network sniffer in qt, cross-platforms
msnwcrec – msn webcam recorder, GPLv2
orionsniffer, tcp/ip packet sniffer, GPLv2, uses winpcap
ansi codes in cmd.exe, article with source code about patching cmd.exe
very sleepy, GPL, simple profiler for windows
FileZill, GPL, C++

Debugging/rec-related code:

opendbg, GPLv3
leaktrap, GPL, gdi/user handle leak tracking and analysis, hooks win32 apis
cdbg, GPLv3, console user-mode debugger
ngdbg, GPLv3, live kernel-mode debugger
openrce-snippets, MIT,
pefile, MIT, Python library to work with pe format
paimei, GPLv2, reverse engineering framework in pyton
vmachine, PC emulator

Debugging,rec tools:

peid, unpacker, decryptor of pe files for win, also has process viewer, pe details, disassembler etc.

PDF-related source code:

openjpeg, New BSD, JPEG 2000 in C

Forcing basic http authentication for HttpWebRequest (in .NET/C#)

2009-03-14T23:12:55Z

HttpWebRequest is a handy .NET class for doing HTTP requests. It has built-in support for HTTP basic authentication via credentials. However, it doesn’t work the way I expected: supplying credentials doesn’t send Authorization HTTP header with the request but only in response to server’s challenge. It often breaks in real world, where servers might not issue a challenge and simply not authenticate a request.

Fortunately fixing it by manually adding Authorization HTTP header to the request is simple and this code snippet shows how to do it:

public void SetBasicAuthHeader(WebRequest req, String userName, String userPassword)
{
    string authInfo = userName + ":" + userPassword;
    authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
    req.Headers["Authorization"] = "Basic " + authInfo;
}

WTL resources

2009-03-14T22:56:22Z

WTL programming resources:

WTL articles on codeproject.com
Threads for WTL
INET for WTL
WTL for MFC: ATL GUI Classes
WTL for MFC: WTL GUI Base Classes
WTL for MFC: toolbars and status bars
WTL for MFC: dialogs and controls
WTL for MFC: advanced dialog ui classes
WTL for MFC: Hosting ActiveX controls
WTL for MFC: Splitter Windows
WTL for MFC: Property Sheets and Wizards
WTL for MFC: GDI Classes, common dialogs and utility classes
WTL for MFC: drag & drop source
Using WTL‘s Built-in Dialog Resizing Class
10 WTL tips (window creation size, centering a window, setting min/max size of a window, dialog text and background color, dynamically swap buttons, default font)
Creating dialogs at runtime
Saving window state
Sizing framework based on WinMgr sizing article

scdiff update (Windows git/subversion/cvs gui diff previewer)

2009-03-12T04:40:44Z

I’ve updated my little scdiff program and added git support.

If you work with git, Subversion or CVS from command line, scdiff is a handy program to preview your changes before committing them.

It works by creating before/after files in a temporary directory and launching a diff viewer (WinDiff by default, but can be configured) to show the diffs.

It auto-detects which scm is being used in a given directory, so you launch it by simply typing scdiff.

It requires git/svn/cvs executable be in the path. There still is no decent windows build of git, so I use cygwin to get git.

Parsing s3 log files in python

2009-03-08T23:54:37Z

After we took care of compacting s3 logs, it’s time to parse them. s3 log format is well documented and can be parsed with a simple regular expression.

It took me some time to craft it, so here it is. You can also view the source here

#!/usr/bin/env python
import re

s3_line_logpats  = r'(\S+) (\S+) \[(.*?)\] (\S+) (\S+) ' \
           r'(\S+) (\S+) (\S+) "([^"]+)" ' \
           r'(\S+) (\S+) (\S+) (\S+) (\S+) (\S+) ' \
           r'"([^"]+)" "([^"]+)"'

s3_line_logpat = re.compile(s3_line_logpats)

(S3_LOG_BUCKET_OWNER, S3_LOG_BUCKET, S3_LOG_DATETIME, S3_LOG_IP,
S3_LOG_REQUESTOR_ID, S3_LOG_REQUEST_ID, S3_LOG_OPERATION, S3_LOG_KEY,
S3_LOG_HTTP_METHOD_URI_PROTO, S3_LOG_HTTP_STATUS, S3_LOG_S3_ERROR,
S3_LOG_BYTES_SENT, S3_LOG_OBJECT_SIZE, S3_LOG_TOTAL_TIME,
S3_LOG_TURN_AROUND_TIME, S3_LOG_REFERER, S3_LOG_USER_AGENT) = range(17)

s3_names = ("bucket_owner", "bucket", "datetime", "ip", "requestor_id", 
"request_id", "operation", "key", "http_method_uri_proto", "http_status", 
"s3_error", "bytes_sent", "object_size", "total_time", "turn_around_time",
"referer", "user_agent")

def parse_s3_log_line(line):
    match = s3_line_logpat.match(line)
    result = [match.group(1+n) for n in range(17)]
    return result

def dump_parsed_s3_line(parsed):
    for (name, val) in zip(s3_names, parsed):
        print("%s: %s" % (name, val))

def test():
    l = r'607c4573f2972c26aff39f7e56ff0490881a35c19b9bf94072cbab8c3219f948 kjkpub [06/Mar/2009:23:13:28 +0000] 41.221.20.231 65a011a29cdf8ec533ec3d1ccaae921c C46E93FF2E865AC1 REST.GET.OBJECT sumatrapdf/rel/SumatraPDF-0.9.1.zip "GET /sumatrapdf/rel/SumatraPDF-0.9.1.zip HTTP/1.1" 206 - 43457 1003293 697 611 "http://kjkpub.s3.amazonaws.com/sumatrapdf/rel/" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)"'
    parsed = parse_s3_log_line(l)
    dump_parsed_s3_line(parsed)

if __name__ == "__main__":
    test()

This snippet only shows how to break one s3 log line into its components (parse_s3_log_line). Some work is needed to build upon this for parsing log files and extracting useful information out of them. For doing that, I recommend techniques described in Generator Tricks for Systems Programmers