36 lines
1.1 KiB
Plaintext
36 lines
1.1 KiB
Plaintext
/** \page page_spa_design SPA Design
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# Conventions
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## Types
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Types are generally divided into two categories:
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- String types: They identify interfaces and highlevel object types.
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- Integer types: These are enumerations used in the parts where high
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performance/ease of use/low space overhead is needed.
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The SPA type is system is statis and very simple but still allows you
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to make and introspect complex object type hierarchies.
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See the type system docs for more info.
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## Error Codes
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SPA uses negative integers as errno style error codes. Functions that return an
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int result code generated an error when < 0. `spa_strerror()` can be used to
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get a string representation of the error code.
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SPA also has a way to encode asynchronous results. This is done by setting a
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high bit (bit 30, the `ASYNC_BIT`) in the result code and a sequence number
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in the lower bits. This result is normally identified as a positive success
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result code and the sequence number can later be matched to the completion
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event.
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## Useful Macros
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SPA comes with some useful macros defined in `<spa/utils/defs.h>` and a
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number of utility functions, see \ref spa_utils.
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*/
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