linux/tools/testing/selftests/powerpc/nx-gzip/README
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   1Test the nx-gzip function:
   2=========================
   3
   4Verify that following device exists:
   5  /dev/crypto/nx-gzip
   6If you get a permission error run as sudo or set the device permissions:
   7   sudo chmod go+rw /dev/crypto/nx-gzip
   8However, chmod may not survive across boots. You may create a udev file such
   9as:
  10   /etc/udev/rules.d/99-nx-gzip.rules
  11
  12
  13To manually build and run:
  14$ gcc -O3 -I./include -o gzfht_test gzfht_test.c gzip_vas.c
  15$ gcc -O3 -I./include -o gunz_test gunz_test.c gzip_vas.c
  16
  17
  18Compress any file using Fixed Huffman mode. Output will have a .nx.gz suffix:
  19$ ./gzfht_test gzip_vas.c
  20file gzip_vas.c read, 6413 bytes
  21compressed 6413 to 3124 bytes total, crc32 checksum = abd15e8a
  22
  23
  24Uncompress the previous output. Output will have a .nx.gunzip suffix:
  25./gunz_test gzip_vas.c.nx.gz
  26gzHeader FLG 0
  2700 00 00 00 04 03
  28gzHeader MTIME, XFL, OS ignored
  29computed checksum abd15e8a isize 0000190d
  30stored   checksum abd15e8a isize 0000190d
  31decomp is complete: fclose
  32
  33
  34Compare two files:
  35$ sha1sum gzip_vas.c.nx.gz.nx.gunzip gzip_vas.c
  36bf43e3c0c3651f5f22b6f9784cd9b1eeab4120b6  gzip_vas.c.nx.gz.nx.gunzip
  37bf43e3c0c3651f5f22b6f9784cd9b1eeab4120b6  gzip_vas.c
  38
  39
  40Note that the code here are intended for testing the nx-gzip hardware function.
  41They are not intended for demonstrating performance or compression ratio.
  42By being simplistic these selftests expect to allocate the entire set of source
  43and target pages in the memory so it needs enough memory to work.
  44For more information and source code consider using:
  45https://github.com/libnxz/power-gzip
  46