> Almost all popular applications on flathub come with filesystem=host, filesystem=home or device=all permissions, that is, write permissions to the user home directory (and more), this effectively means that all it takes to "escape the sandbox" is echo download_and_execute_evil >> ~/.bashrc. That's it.

> To make matters worse, the users are misled to believe the apps run sandboxed. For all these apps flatpak shows a reassuring "sandbox" icon when installing the app (things do not get much better even when installing in the command line - you need to know flatpak internals to understand the warnings).

I have not used flatpack. Is this description accurate? Also:

> Up until 0.8.7 all it took to get root on the host was to install a flatpak package that contains a suid binary (flatpaks are installed to /var/lib/flatpak on your host system). Again, could this be any easier? A high severity CVE-2017-9780 (CVSS Score 7.2) has indeed been assigned to this vulnerability. Flatpak developers consider this a minor security issue.

The data URI scheme is standard and widely supported, does not rely on the host bitty.site being reachable and does not need JavaScript. One can even create data URIs with a small shell script that is given a filename argument:

  #!/bin/sh -eu
  printf 'data:%s;base64,%s' "$(file -bi "$1"|tr -d ' ')" "$(base64 -w 0 "$1")"

  #!/bin/sh
  redo-ifchange $2.c
  strace -e stat,stat64,fstat,fstat64,lstat,lstat64 -f 2>&1 >/dev/null\
   gcc $2.c -o $3 -MD -MF $2.deps\
   |grep '1 ENOENT'\
   |grep '\.h'\
   |cut -d'"' -f2 2>/dev/null\
   >$2.deps_ne
  
  read d <$2.deps
  redo-ifchange ${d#*:}
  
  while read -r d_ne; do
   redo-ifcreate $d_ne
  done <$2.deps_ne
  
  chmod a+x $3

I think the compiler should output the necessary information. To quote Jonathan de Boyne Pollard [3]:

> As noted earlier, no C or C++ compiler currently generates any redo-ifcreate dependency information, only the redo-ifchange dependency information. This is a deficiency of the compilers rather than a deficiency of redo, though. That the introduction of a new higher-precedence header earlier on the include path will affect recompilation is a fact that almost all C/C++ build systems fail to account for.

> I have written, but not yet released, a C++ tool that is capable of generating both redo-ifchange information for included files and redo-ifcreate information for the places where included files were searched for but didn't exist, and thus where adding new (different) included files would change the output.

JdeBP, could you please release your tool under a free software license? I suspect it has fewer errors than the similar CMake approach [4].

[1] http://news.dieweltistgarnichtso.net/posts/redo-gcc-automati...

[2] https://github.com/linleyh/liberation-circuit/blob/master/sr...

[3] http://jdebp.eu./FGA/introduction-to-redo.html#CompilerDefic...

[4] https://github.com/Kitware/CMake/blob/master/Source/cmDepend...

Also, how does scons handle non-existence dependencies?

What would be a scons dependency graph for this C code?

  #include
  main() {
   printf("hello, world\n");
   return 0;
  }

I wrote a blog post to show how to integrate dependency output for both dependency and non-existence dependency generation [2]. The game “Liberation Circuit” can be built with my redo implementation; you can output a dependency graph usable with Graphviz [4] using “redo-dot”.

There is only one other redo implementation that I would recommend, the one from Jonathan de Boyne Pollard [5], who rightly notices that compilers should output information about non-existence dependencies [6].

I would not recommend the redo implementation from Avery Pennarun [7], which is often referenced (and introduced me to the concept), mainly because it is not implemented well: It manages to be both larger and slower than my shell script implementation, yet the documentation says this about the sqlite dependency (classic case of premature optimization):

> I don't think we can reach the performance we want with dependency/build/lock information stored in plain text files

[0] http://cr.yp.to/redo.html

[1] http://news.dieweltistgarnichtso.net/bin/redo-sh.html

[2] http://news.dieweltistgarnichtso.net/posts/redo-gcc-automati...

[3] https://github.com/linleyh/liberation-circuit

[4] https://en.wikipedia.org/wiki/Graphviz

[5] http://jdebp.eu./Softwares/redo/

[6] http://jdebp.eu./FGA/introduction-to-redo.html#CompilerDefic...

[7] https://github.com/apenwarr/redo

> Especially when using C or C++, often target files depend on nonexistent files as well, meaning that a target file should be rebuilt when a previosly nonexistent file is created: If the preprocessor includes /usr/include/stdio.h because it could not find /usr/local/include/stdio.h, the creation of the latter file should trigger a rebuild.

I did some research on the topic using the repository of the game Liberation Circuit [3] and my own redo implementation [4] … it turns out that a typical project in C or C++ has lots of non-existence dependencies. How do make users handle non-existence dependencies – except for always calling “make clean”?

[1] http://cr.yp.to/redo/honest-nonfile.html

[2] http://news.dieweltistgarnichtso.net/posts/redo-gcc-automati...

[3] https://github.com/linleyh/liberation-circuit

[4] http://news.dieweltistgarnichtso.net/bin/redo-sh.html (redo-dot gives a graph of dependencies and non-existence dependencies)

I plan to work on POSIX compatibility for my redo implementation.

Also, have you looked at the redo tool redo-ifcreate? http://news.dieweltistgarnichtso.net/bin/redo-sh.html

http://news.dieweltistgarnichtso.net/posts/redo-gcc-automati...

> In 2014, Nils Dagsson Moskopp re-implemented Pennarun redo, retargetting it at the Bourne Again shell and BusyBox.

I targeted the Bourne Shell (sh), not the Bourne Again Shell (bash). Also, my redo implementation contains redo-dot that paints a dependency-tree – I have not seen this otherwere.

Quote:

   * Add Enhances: caja, tumbler (>= 0.1.92~), nautilus, nemo
     These are some of the many file managers/thumbnailer programs that support
     desktop thumbnailers like exe-thumbnailer, and I have verified (at some
     point) that all of these work.

Comments URL: https://news.ycombinator.com/item?id=14790446

Points: 3

# Comments: 0

Separation of concerns is a thing that can help designers, no?

I think SPAs are either fundamentally dishonest engineering, in the same way that a microwave wrapped in artificial wood veneer is (and a stainless steel microwave is not) or should result in such a template. If you really think that this is too much, IMO you should not make an SPA in the first place.

Making sure the result conforms to the grammar of the output language without any unparser would always involve a parser.

> As soon as I'm looking at more than one programming or markup language in the same file, I'm looking at spaghetti code.

Iain Dooley, December 2011

http://www.workingsoftware.com.au/page/Your_templating_engin...

Source: https://news.ycombinator.com/item?id=14162399

Hello Hayan Zhang,

I have read several articles about the “Emma device” you have built, but could not find any details. Have you published source code & schematics?

The BBC has a GitHub repository for code related to the documentary. The one open issue on it is from a person who wants to help their father who has been affected by Parkinson's <https://github.com/bbc/MiD/issues/3>:

> I am hoping to design a similar item to help my father with both > writing, and potentially in continuing other activities that his > Parkinson's is starting to inhibit, and while the Big Life Fix episode > covering it gave some hints at the details, there wasn't that much > concrete information.

In a Reddit thread, other people also want to know how the “Emma device” works and built it for their relatives who are afflicted by Parkinson's: <https://www.reddit.com/r/Parkinsons/comments/5hh2fx/emmas_wa...

Since you seem to have zero interest in commercializing your findings, I do not understand why the information on the details seems hard to find. Have you published something (like a scientific article) on the subject?

Greetings,