glsl: Add initial functions to implement an on-disk cache
This code provides for an on-disk cache of objects. Objects are stored and retrieved via names that are arbitrary 20-byte sequences, (intended to be SHA-1 hashes of something identifying for the content). The directory used for the cache can be specified by means of environment variables in the following priority order: $MESA_GLSL_CACHE_DIR $XDG_CACHE_HOME/mesa <user-home-directory>/.cache/mesa By default the cache will be limited to a maximum size of 1GB. The environment variable: $MESA_GLSL_CACHE_MAX_SIZE can be set (at the time of GL context creation) to choose some other size. This variable is a number that can optionally be followed by 'K', 'M', or 'G' to select a size in kilobytes, megabytes, or gigabytes. By default, an unadorned value will be interpreted as gigabytes. The cache will be entirely disabled at runtime if the variable MESA_GLSL_CACHE_DISABLE is set at the time of GL context creation. Many thanks to Kristian Høgsberg <krh@bitplanet.net> for the initial implementation of code that led to this patch. In particular, the idea of using an mmapped file, (indexed by a portion of the SHA-1), for the efficent implementation of cache_has_key was entirely his idea. Kristian also provided some very helpful advice in discussions regarding various race conditions to be avoided in this code. Signed-off-by:Timothy Arceri <timothy.arceri@collabora.com> Reviewed-by:
Eric Anholt <eric@anholt.net>
- configure.ac 3 additions, 0 deletionsconfigure.ac
- src/compiler/Makefile.glsl.am 10 additions, 0 deletionssrc/compiler/Makefile.glsl.am
- src/compiler/Makefile.sources 4 additions, 0 deletionssrc/compiler/Makefile.sources
- src/compiler/glsl/cache.c 710 additions, 0 deletionssrc/compiler/glsl/cache.c
- src/compiler/glsl/cache.h 172 additions, 0 deletionssrc/compiler/glsl/cache.h
- src/compiler/glsl/tests/.gitignore 1 addition, 0 deletionssrc/compiler/glsl/tests/.gitignore
- src/compiler/glsl/tests/cache_test.c 416 additions, 0 deletionssrc/compiler/glsl/tests/cache_test.c