1//===- FormatCommon.h - Formatters for common LLVM types --------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLVM_SUPPORT_FORMATCOMMON_H
10#define LLVM_SUPPORT_FORMATCOMMON_H
11
12#include "llvm/ADT/SmallString.h"
13#include "llvm/Support/FormatVariadicDetails.h"
14#include "llvm/Support/raw_ostream.h"
15
16namespace llvm {
17enum class AlignStyle { Left, Center, Right };
18
19struct FmtAlign {
20 detail::format_adapter &Adapter;
21 AlignStyle Where;
22 size_t Amount;
23 char Fill;
24
25 FmtAlign(detail::format_adapter &Adapter, AlignStyle Where, size_t Amount,
26 char Fill = ' ')
27 : Adapter(Adapter), Where(Where), Amount(Amount), Fill(Fill) {}
28
29 void format(raw_ostream &S, StringRef Options) {
30 // If we don't need to align, we can format straight into the underlying
31 // stream. Otherwise we have to go through an intermediate stream first
32 // in order to calculate how long the output is so we can align it.
33 // TODO: Make the format method return the number of bytes written, that
34 // way we can also skip the intermediate stream for left-aligned output.
35 if (Amount == 0) {
36 Adapter.format(S, Options);
37 return;
38 }
39 SmallString<64> Item;
40 raw_svector_ostream Stream(Item);
41
42 Adapter.format(S&: Stream, Options);
43 if (Amount <= Item.size()) {
44 S << Item;
45 return;
46 }
47
48 size_t PadAmount = Amount - Item.size();
49 switch (Where) {
50 case AlignStyle::Left:
51 S << Item;
52 fill(S, Count: PadAmount);
53 break;
54 case AlignStyle::Center: {
55 size_t X = PadAmount / 2;
56 fill(S, Count: X);
57 S << Item;
58 fill(S, Count: PadAmount - X);
59 break;
60 }
61 default:
62 fill(S, Count: PadAmount);
63 S << Item;
64 break;
65 }
66 }
67
68private:
69 void fill(llvm::raw_ostream &S, size_t Count) {
70 for (size_t I = 0; I < Count; ++I)
71 S << Fill;
72 }
73};
74}
75
76#endif
77

source code of llvm/include/llvm/Support/FormatCommon.h