MPD  0.20.15
Set.hxx
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1 /*
2  * Copyright 2003-2017 The Music Player Daemon Project
3  * http://www.musicpd.org
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
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13  * GNU General Public License for more details.
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18  */
19 
20 #ifndef MPD_TAG_SET_HXX
21 #define MPD_TAG_SET_HXX
22 
23 #include "Compiler.h"
24 #include "Tag.hxx"
25 #include "Mask.hxx"
26 
27 #include <set>
28 
29 #include <string.h>
30 
34 struct TagLess {
35  gcc_pure
36  bool operator()(const Tag &a, const Tag &b) const noexcept {
37  if (a.num_items != b.num_items)
38  return a.num_items < b.num_items;
39 
40  const unsigned n = a.num_items;
41  for (unsigned i = 0; i < n; ++i) {
42  const TagItem &ai = *a.items[i];
43  const TagItem &bi = *b.items[i];
44  if (ai.type != bi.type)
45  return unsigned(ai.type) < unsigned(bi.type);
46 
47  const int cmp = strcmp(ai.value, bi.value);
48  if (cmp != 0)
49  return cmp < 0;
50  }
51 
52  return false;
53  }
54 };
55 
59 class TagSet : public std::set<Tag, TagLess> {
60 public:
61  void InsertUnique(const Tag &tag,
62  TagType type, tag_mask_t group_mask) noexcept;
63 
64 private:
65  void InsertUnique(const Tag &src, TagType type, const char *value,
66  tag_mask_t group_mask) noexcept;
67 
68  bool CheckUnique(TagType dest_type,
69  const Tag &tag, TagType src_type,
70  tag_mask_t group_mask) noexcept;
71 };
72 
73 #endif
TagType type
the type of this item
Definition: TagItem.hxx:32
The meta information about a song file.
Definition: Tag.hxx:34
Helper class for TagSet which compares two Tag objects.
Definition: Set.hxx:34
TagType
Codes for the type of a tag item.
Definition: TagType.h:30
One tag value.
Definition: TagItem.hxx:30
char value[1]
the value of this tag; this is a variable length string
Definition: TagItem.hxx:37
uint_least32_t tag_mask_t
Definition: Mask.hxx:25
gcc_pure bool operator()(const Tag &a, const Tag &b) const noexcept
Definition: Set.hxx:36
A set of Tag objects.
Definition: Set.hxx:59
void InsertUnique(const Tag &tag, TagType type, tag_mask_t group_mask) noexcept
#define gcc_pure
Definition: Compiler.h:116