Android native C Development 5: zlib porting notes

Original article: http://blog.sina.com.cn/s/blog_4a0a39c30100b4ao.html

 

 

Zlib (http://www.zlib.net/) is a very popular and open-source compression, decompression library, by Jean-Loup
Gailly and Mark
Developed by Adler, the first version of 0.9 was published in May 1, 1995. Zlib uses the deflate algorithm, which was originally written for the libpng function library. Later, zlib was widely used by many software.

The current zlib version is
1.2.3. It has excellent portability. I have successfully transplanted zlib to Windows, Linux, WinCE, Symbian, and other platforms. Of course, it also includes the platform to be transplanted today: Android.

First, download the source code of zlib from the official website of zlib: zlib123.zip, decompress it to get a directory zlib-1.2.3, Zib has provided a makefile, you can modify several lines (19, 20, 27, 36, and 37) to compile them. The changes are as follows:

...... Cc = arm-None-Linux-gnueabi-gcc Cflags = -O2 ...... Ldflags = libz. A-s-static ...... AR = Arm-None-Linux-gnueabi-ar RC Ranlib = arm-None-Linux-gnueabi-ranlib ......

Go to the zlib-1.2.3 directory and enter: make on the command line.

Finally, two executable Android files are generated: Example and minigzip.

Run the android simulator, enter the command line, push two executable files to the android simulator, and then execute the command as follows:

 

$ ADB push example /Dev/sample/Example $ ADB Push minigzip/dev/sample/minigzip $ ADB shell chmod 777/dev/sample /* $ ADB Shell # Cd/dev/sample #./Example Zlib version 1.2.3 = 0x1230, compile flags = 0x55 Uncompress (): Hello, hello! Gzread (): Hello, hello! Gzgets () after gzseek: Hello! Inflate (): Hello, hello! Large_inflate (): OK After inflatesync (): Hello, hello! Inflate with dictionary: Hello, hello! # Ls-l Ls-l -Rwxrwxrwx Root Root 513228 minigzip -Rwxrwxrwx Root Root 517640 example -Rwxrwxrwx Root Root 31 foo.gz # Exit $ ADB pull/dev/sample/foo.gz D:/foo.gz

"$" Indicates the Linux or cygwin command line prompt, and # indicates the android command line prompt.

Finally, run the LS-l command to view the current directory. A foo.gz file is generated by example and stops ADB.
Shell. Run the command ADB pull/dev/sample/foo.gz D:/foo.gz to run the file foo.gz generated on the simulator.
Pull to the root directory of drive D. You can use WinRAR or 7zip to view the content of this file, which is exactly the "Hello, hello!" file written in the code! "!

 

So far, zlib has been successfully transplanted to the Android platform!