34 lines
2.5 KiB
C
34 lines
2.5 KiB
C
/* bits/errno-return.h: A convenient way of setting errno after a syscall. */
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#ifndef _BITS_ERRNO_RETURN_H
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#define _BITS_ERRNO_RETURN_H
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#include <errno.h>
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// Set errno after a failed system call, otherwise extract the successful value.
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#define __errno_return(value, type) \
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do { \
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if (value < 0) \
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{ \
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errno = (int)(-value); \
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return (type) - 1; \
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} \
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return (type)value; \
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} while (0)
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// If expr has a value, evaluates to that value. Otherwise, short-circuits, sets errno to expr's error, and returns
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// failval (casted to rtype) from the calling function. Similar to TRY() in luna/Result.h, but used for transforming
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// errors from luna functions to libc functions.
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#define TRY_OR_SET_ERRNO(expr, rtype, failval) \
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({ \
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auto _expr_rc = (expr); \
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if (!_expr_rc.has_value()) \
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{ \
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errno = _expr_rc.error(); \
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return (rtype)failval; \
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} \
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_expr_rc.release_value(); \
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})
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#endif
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