41 lines
753 B
Go
41 lines
753 B
Go
package builtins
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import (
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"monkey/internal/object"
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"monkey/internal/typing"
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"syscall"
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)
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// DefaultBufferSize is the default buffer size
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const DefaultBufferSize = 4096
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// Read ...
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func Read(args ...object.Object) object.Object {
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if err := typing.Check(
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"read", args,
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typing.RangeOfArgs(1, 2),
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typing.WithTypes(object.INTEGER_OBJ, object.INTEGER_OBJ),
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); err != nil {
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return newError(err.Error())
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}
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var (
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fd int
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n = DefaultBufferSize
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)
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fd = int(args[0].(*object.Integer).Value)
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if len(args) == 2 {
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n = int(args[1].(*object.Integer).Value)
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}
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buf := make([]byte, n)
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n, err := syscall.Read(syscall.Handle(fd), buf)
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if err != nil {
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return newError("IOError: %s", err)
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}
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return &object.String{Value: string(buf[:n])}
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}
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