43cbcbf319
Technically, the only serious problem in this function was the code:
local tmp = assert(io.popen('unzip -l \"'..fname..'\"', "r"))
while tmp do
s = tmp:read("*line")
if i > 3 then tmp:close(); break; end
i = i + 1
end
It is meaningless to evaluate the truth of the return value of assert()
and the above code gives the impression that it relies on the
(undocumented and unreliable) fact that after tmp:close() tmp will be
nil, even though in actual fact it does because it breaks out of the
loop.
However, having looked at the function I saw that the whole thing
can be rewritten in a much simpler way:
local tmp = assert(io.popen('unzip -l \"'..fname..'\" | head -4 | tail -1', "r"))
s = tmp:read("*line")
tmp:close()
KindlePDFViewer
This is a PDF viewer application, created for usage on the Kindle e-ink reader. It is currently restricted to 4bpp inverse grayscale displays. It's using the muPDF library (see http://mupdf.com/) and its UI is scripted using Lua (see http://www.lua.org/).
The application is licensed under the GPLv3 (see COPYING file).
Building
Follow these steps:
-
fetch thirdparty sources
-
manually fetch all the thirdparty sources:
- install muPDF sources into subfolder "mupdf"
- install muPDF third-party sources (see muPDF homepage) into a new subfolder "mupdf/thirdparty"
- install libDjvuLibre sources into subfolder "djvulibre"
- install CREngine sources into subfolder "kpvcrlib/crengine"
- install LuaJit sources into subfolder "luajit-2.0"
-
automatically fetch thirdparty sources with Makefile:
- make sure you have wget, unzip and git installed
- run
make fetchthirdparty.
-
-
adapt Makefile to your needs
-
run
make thirdparty. This will build MuPDF (plus the libraries it depends on), libDjvuLibre, CREngine and Lua. -
run
make. This will build the kpdfview application
Running
The user interface (or what's there yet) is scripted in Lua. See "reader.lua". It uses the Linux feature to run scripts by using a corresponding line at its start.
So you might just call that script. Note that the script and the kpdfview binary currently must be in the same directory.
You would then just call reader.lua, giving the document file path, or any directory path, as its first argument. Run reader.lua without arguments to see usage notes. The reader.lua script can also show a file chooser: it will do this when you call it with a directory (instead of a file) as first argument.
Device emulation
The code also features a device emulation. You need SDL headers and library for this. It allows to develop on a standard PC and saves precious development time. It might also compose the most unfriendly desktop PDF reader, depending on your view.
If you are using Ubuntu, simply install libsdl-dev1.2 package.
To build in "emulation mode", you need to run make like this: make clean cleanthirdparty EMULATE_READER=1 make thirdparty kpdfview
And run the emulator like this:
./reader.lua /PATH/TO/PDF.pdf
or:
./reader.lua /ANY/PATH
By default emulation will provide DXG resolution of 824*1200. It can be specified at compile time, this is example for Kindle 3:
EMULATE_READER_W=600 EMULATE_READER_H=800 EMULATE_READER=1 make kpdfview