1//===-- GlobPattern.h - glob pattern matcher implementation -*- 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// This file implements a glob pattern matcher.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_SUPPORT_GLOBPATTERN_H
14#define LLVM_SUPPORT_GLOBPATTERN_H
15
16#include "llvm/ADT/BitVector.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/ADT/StringRef.h"
19#include "llvm/Support/Error.h"
20#include <optional>
21
22namespace llvm {
23
24/// This class implements a glob pattern matcher similar to the one found in
25/// bash, but with some key differences. Namely, that \p "*" matches all
26/// characters and does not exclude path separators.
27///
28/// * \p "?" matches a single character.
29/// * \p "*" matches zero or more characters.
30/// * \p "[<chars>]" matches one character in the bracket. Character ranges,
31/// e.g., \p "[a-z]", and negative sets via \p "[^ab]" or \p "[!ab]" are also
32/// supported.
33/// * \p "{<glob>,...}" matches one of the globs in the list. Nested brace
34/// expansions are not supported. If \p MaxSubPatterns is empty then
35/// brace expansions are not supported and characters \p "{,}" are treated as
36/// literals.
37/// * \p "\" escapes the next character so it is treated as a literal.
38///
39///
40/// Some known edge cases are:
41/// * \p "]" is allowed as the first character in a character class, i.e.,
42/// \p "[]]" is valid and matches the literal \p "]".
43/// * The empty character class, i.e., \p "[]", is invalid.
44/// * Empty or singleton brace expansions, e.g., \p "{}", \p "{a}", are invalid.
45/// * \p "}" and \p "," that are not inside a brace expansion are taken as
46/// literals, e.g., \p ",}" is valid but \p "{" is not.
47///
48///
49/// For example, \p "*[/\\]foo.{c,cpp}" will match (unix or windows) paths to
50/// all files named \p "foo.c" or \p "foo.cpp".
51class GlobPattern {
52public:
53 /// \param Pat the pattern to match against
54 /// \param MaxSubPatterns if provided limit the number of allowed subpatterns
55 /// created from expanding braces otherwise disable
56 /// brace expansion
57 static Expected<GlobPattern>
58 create(StringRef Pat, std::optional<size_t> MaxSubPatterns = {});
59 /// \returns \p true if \p S matches this glob pattern
60 bool match(StringRef S) const;
61
62 // Returns true for glob pattern "*". Can be used to avoid expensive
63 // preparation/acquisition of the input for match().
64 bool isTrivialMatchAll() const {
65 if (!Prefix.empty())
66 return false;
67 if (SubGlobs.size() != 1)
68 return false;
69 return SubGlobs[0].getPat() == "*";
70 }
71
72private:
73 StringRef Prefix;
74
75 struct SubGlobPattern {
76 /// \param Pat the pattern to match against
77 static Expected<SubGlobPattern> create(StringRef Pat);
78 /// \returns \p true if \p S matches this glob pattern
79 bool match(StringRef S) const;
80 StringRef getPat() const { return StringRef(Pat.data(), Pat.size()); }
81
82 // Brackets with their end position and matched bytes.
83 struct Bracket {
84 size_t NextOffset;
85 BitVector Bytes;
86 };
87 SmallVector<Bracket, 0> Brackets;
88 SmallVector<char, 0> Pat;
89 };
90 SmallVector<SubGlobPattern, 1> SubGlobs;
91};
92}
93
94#endif // LLVM_SUPPORT_GLOBPATTERN_H
95

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