98 lines
2.5 KiB
Markdown
98 lines
2.5 KiB
Markdown
## Documentation
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How to document the code::
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/*! This is a small comment on one line
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*
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* This is a detailed description
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* spanning several lines.
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*
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* Example usage:
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* @code
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* fn(a, &b);
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* @endcode
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*
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* @param[in] src This is a description of the first parameter
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* @param[in,out] dest This is a description of the second parameter
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* @retval TRUE This is a description of the return value
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* @retval FALSE This is a description of another return value
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* @see See also this function
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*/
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## C style
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Clixon uses 4-char indentation, a la emacs "cc-mode".
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### Function declarations
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Functions in C code are written as follows::
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static int
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myfn(int par1,
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my_structure *par2)
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{
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int retval = -1;
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my_structure *ms;
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ms = NULL;
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Notes:
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1. the return type of the function and all qualifers on first line (`static int`)
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2. function name and first parameter on second line, thereafter each parameter on own line
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3. Each parameter indented to match the "longest" (`my_structure`)
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4. Pointer declarations written: `type *p`, not: `type* p`.
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5. All local variables in a function declared at top of function, not inline with C-statements.
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6. Local variables can be initialized with scalars or constants, not eg malloc or functions with return values that need to be checked for errors
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7. There is a single empty line between local variable declarations and the first function statement.
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Function signatures are declared in include files or in forward declaration using "one-line" syntax, unless very long::
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static int myfn(int par1, my_structure *par2);
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### Errors
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Errors are typically declared as follows::
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if (myfn(0) < 0){
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clicon_err(OE_UNIX, EINVAL, "myfn");
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goto done;
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}
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All function returns that have return values must be checked
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Default return values form a function are:
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- `0` OK
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- `-1` Fatal Error
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In some cases, Clixon uses three-value returns as follows:
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- `1` OK
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- `0` Invalid
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- `-1` Fatal error
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### Return values
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Clixon uses goto:s only to get a single point of exit functions as follows::
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{
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int retval = -1;
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...
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retval = 0;
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done:
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return retval
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}
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Notes:
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1. Use only a single return statement in a function
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2. Do not use of goto:s in other ways
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### Comments
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Use `/* */`. Use `//` only for temporal comments.
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Do not use "======", ">>>>>" or "<<<<<<" in comments since git merge conflict uses that.
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