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1 | 1 | // Copyright 2018-2023 Georges Racinet <georges.racinet@octobus.net> |
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2 | 2 | // and Mercurial contributors |
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3 | 3 | // |
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4 | 4 | // This software may be used and distributed according to the terms of the |
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5 | 5 | // GNU General Public License version 2 or any later version. |
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6 | 6 | //! Mercurial concepts for handling revision history |
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7 | 7 | |
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8 | 8 | pub mod node; |
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9 | 9 | pub mod nodemap; |
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10 | 10 | mod nodemap_docket; |
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11 | 11 | pub mod path_encode; |
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12 | 12 | pub use node::{FromHexError, Node, NodePrefix}; |
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13 | 13 | pub mod changelog; |
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14 | 14 | pub mod filelog; |
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15 | 15 | pub mod index; |
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16 | 16 | pub mod manifest; |
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17 | 17 | pub mod patch; |
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18 | 18 | |
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19 | 19 | use std::borrow::Cow; |
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20 | 20 | use std::io::Read; |
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21 | 21 | use std::ops::Deref; |
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22 | 22 | use std::path::Path; |
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23 | 23 | |
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24 | 24 | use flate2::read::ZlibDecoder; |
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25 | 25 | use sha1::{Digest, Sha1}; |
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26 | 26 | use std::cell::RefCell; |
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27 | 27 | use zstd; |
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28 | 28 | |
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29 | 29 | use self::node::{NODE_BYTES_LENGTH, NULL_NODE}; |
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30 | 30 | use self::nodemap_docket::NodeMapDocket; |
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31 | 31 | use super::index::Index; |
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32 | 32 | use super::nodemap::{NodeMap, NodeMapError}; |
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33 | 33 | use crate::errors::HgError; |
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34 | 34 | use crate::vfs::Vfs; |
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35 | 35 | |
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36 | 36 | /// Mercurial revision numbers |
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37 | 37 | /// |
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38 | 38 | /// As noted in revlog.c, revision numbers are actually encoded in |
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39 | 39 | /// 4 bytes, and are liberally converted to ints, whence the i32 |
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40 | 40 | pub type Revision = i32; |
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41 | 41 | |
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42 | 42 | /// Marker expressing the absence of a parent |
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43 | 43 | /// |
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44 | 44 | /// Independently of the actual representation, `NULL_REVISION` is guaranteed |
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45 | 45 | /// to be smaller than all existing revisions. |
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46 | 46 | pub const NULL_REVISION: Revision = -1; |
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47 | 47 | |
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48 | 48 | /// Same as `mercurial.node.wdirrev` |
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49 | 49 | /// |
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50 | 50 | /// This is also equal to `i32::max_value()`, but it's better to spell |
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51 | 51 | /// it out explicitely, same as in `mercurial.node` |
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52 | 52 | #[allow(clippy::unreadable_literal)] |
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53 | 53 | pub const WORKING_DIRECTORY_REVISION: Revision = 0x7fffffff; |
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54 | 54 | |
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55 | 55 | pub const WORKING_DIRECTORY_HEX: &str = |
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56 | 56 | "ffffffffffffffffffffffffffffffffffffffff"; |
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57 | 57 | |
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58 | 58 | /// The simplest expression of what we need of Mercurial DAGs. |
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59 | 59 | pub trait Graph { |
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60 | 60 | /// Return the two parents of the given `Revision`. |
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61 | 61 | /// |
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62 | 62 | /// Each of the parents can be independently `NULL_REVISION` |
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63 | 63 | fn parents(&self, rev: Revision) -> Result<[Revision; 2], GraphError>; |
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64 | 64 | } |
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65 | 65 | |
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66 | 66 | #[derive(Clone, Debug, PartialEq)] |
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67 | 67 | pub enum GraphError { |
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68 | 68 | ParentOutOfRange(Revision), |
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69 | 69 | WorkingDirectoryUnsupported, |
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70 | 70 | } |
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71 | 71 | |
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72 | 72 | /// The Mercurial Revlog Index |
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73 | 73 | /// |
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74 | 74 | /// This is currently limited to the minimal interface that is needed for |
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75 | 75 | /// the [`nodemap`](nodemap/index.html) module |
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76 | 76 | pub trait RevlogIndex { |
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77 | 77 | /// Total number of Revisions referenced in this index |
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78 | 78 | fn len(&self) -> usize; |
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79 | 79 | |
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80 | 80 | fn is_empty(&self) -> bool { |
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81 | 81 | self.len() == 0 |
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82 | 82 | } |
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83 | 83 | |
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84 | 84 | /// Return a reference to the Node or `None` if rev is out of bounds |
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85 | 85 | /// |
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86 | 86 | /// `NULL_REVISION` is not considered to be out of bounds. |
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87 | 87 | fn node(&self, rev: Revision) -> Option<&Node>; |
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88 | 88 | } |
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89 | 89 | |
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90 | 90 | const REVISION_FLAG_CENSORED: u16 = 1 << 15; |
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91 | 91 | const REVISION_FLAG_ELLIPSIS: u16 = 1 << 14; |
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92 | 92 | const REVISION_FLAG_EXTSTORED: u16 = 1 << 13; |
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93 | 93 | const REVISION_FLAG_HASCOPIESINFO: u16 = 1 << 12; |
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94 | 94 | |
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95 | 95 | // Keep this in sync with REVIDX_KNOWN_FLAGS in |
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96 | 96 | // mercurial/revlogutils/flagutil.py |
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97 | 97 | const REVIDX_KNOWN_FLAGS: u16 = REVISION_FLAG_CENSORED |
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98 | 98 | | REVISION_FLAG_ELLIPSIS |
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99 | 99 | | REVISION_FLAG_EXTSTORED |
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100 | 100 | | REVISION_FLAG_HASCOPIESINFO; |
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101 | 101 | |
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102 | 102 | const NULL_REVLOG_ENTRY_FLAGS: u16 = 0; |
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103 | 103 | |
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104 | 104 | #[derive(Debug, derive_more::From)] |
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105 | 105 | pub enum RevlogError { |
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106 | 106 | InvalidRevision, |
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107 | 107 | /// Working directory is not supported |
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108 | 108 | WDirUnsupported, |
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109 | 109 | /// Found more than one entry whose ID match the requested prefix |
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110 | 110 | AmbiguousPrefix, |
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111 | 111 | #[from] |
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112 | 112 | Other(HgError), |
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113 | 113 | } |
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114 | 114 | |
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115 | 115 | impl From<NodeMapError> for RevlogError { |
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116 | 116 | fn from(error: NodeMapError) -> Self { |
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117 | 117 | match error { |
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118 | 118 | NodeMapError::MultipleResults => RevlogError::AmbiguousPrefix, |
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119 | 119 | NodeMapError::RevisionNotInIndex(rev) => RevlogError::corrupted( |
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120 | 120 | format!("nodemap point to revision {} not in index", rev), |
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121 | 121 | ), |
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122 | 122 | } |
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123 | 123 | } |
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124 | 124 | } |
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125 | 125 | |
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126 | 126 | fn corrupted<S: AsRef<str>>(context: S) -> HgError { |
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127 | 127 | HgError::corrupted(format!("corrupted revlog, {}", context.as_ref())) |
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128 | 128 | } |
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129 | 129 | |
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130 | 130 | impl RevlogError { |
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131 | 131 | fn corrupted<S: AsRef<str>>(context: S) -> Self { |
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132 | 132 | RevlogError::Other(corrupted(context)) |
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133 | 133 | } |
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134 | 134 | } |
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135 | 135 | |
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136 | 136 | /// Read only implementation of revlog. |
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137 | 137 | pub struct Revlog { |
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138 | 138 | /// When index and data are not interleaved: bytes of the revlog index. |
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139 | 139 | /// When index and data are interleaved: bytes of the revlog index and |
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140 | 140 | /// data. |
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141 | 141 | index: Index, |
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142 | 142 | /// When index and data are not interleaved: bytes of the revlog data |
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143 | 143 | data_bytes: Option<Box<dyn Deref<Target = [u8]> + Send>>, |
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144 | 144 | /// When present on disk: the persistent nodemap for this revlog |
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145 | 145 | nodemap: Option<nodemap::NodeTree>, |
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146 | 146 | } |
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147 | 147 | |
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148 | 148 | impl Revlog { |
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149 | 149 | /// Open a revlog index file. |
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150 | 150 | /// |
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151 | 151 | /// It will also open the associated data file if index and data are not |
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152 | 152 | /// interleaved. |
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153 | 153 | pub fn open( |
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154 | 154 | store_vfs: &Vfs, |
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155 | 155 | index_path: impl AsRef<Path>, |
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156 | 156 | data_path: Option<&Path>, |
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157 | 157 | use_nodemap: bool, |
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158 | 158 | ) -> Result<Self, HgError> { |
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159 | Self::open_gen(store_vfs, index_path, data_path, use_nodemap, None) | |
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160 | } | |
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161 | ||
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162 | fn open_gen( | |
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163 | store_vfs: &Vfs, | |
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164 | index_path: impl AsRef<Path>, | |
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165 | data_path: Option<&Path>, | |
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166 | use_nodemap: bool, | |
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167 | nodemap_for_test: Option<nodemap::NodeTree>, | |
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168 | ) -> Result<Self, HgError> { | |
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159 | 169 | let index_path = index_path.as_ref(); |
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160 | 170 | let index = { |
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161 | 171 | match store_vfs.mmap_open_opt(&index_path)? { |
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162 | 172 | None => Index::new(Box::new(vec![])), |
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163 | 173 | Some(index_mmap) => { |
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164 | 174 | let index = Index::new(Box::new(index_mmap))?; |
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165 | 175 | Ok(index) |
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166 | 176 | } |
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167 | 177 | } |
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168 | 178 | }?; |
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169 | 179 | |
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170 | 180 | let default_data_path = index_path.with_extension("d"); |
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171 | 181 | |
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172 | 182 | // type annotation required |
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173 | 183 | // won't recognize Mmap as Deref<Target = [u8]> |
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174 | 184 | let data_bytes: Option<Box<dyn Deref<Target = [u8]> + Send>> = |
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175 | 185 | if index.is_inline() { |
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176 | 186 | None |
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177 | 187 | } else { |
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178 | 188 | let data_path = data_path.unwrap_or(&default_data_path); |
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179 | 189 | let data_mmap = store_vfs.mmap_open(data_path)?; |
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180 | 190 | Some(Box::new(data_mmap)) |
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181 | 191 | }; |
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182 | 192 | |
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183 | 193 | let nodemap = if index.is_inline() || !use_nodemap { |
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184 | 194 | None |
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185 | 195 | } else { |
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186 | 196 | NodeMapDocket::read_from_file(store_vfs, index_path)?.map( |
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187 | 197 | |(docket, data)| { |
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188 | 198 | nodemap::NodeTree::load_bytes( |
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189 | 199 | Box::new(data), |
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190 | 200 | docket.data_length, |
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191 | 201 | ) |
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192 | 202 | }, |
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193 | 203 | ) |
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194 | 204 | }; |
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195 | 205 | |
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206 | let nodemap = nodemap_for_test.or(nodemap); | |
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207 | ||
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196 | 208 | Ok(Revlog { |
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197 | 209 | index, |
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198 | 210 | data_bytes, |
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199 | 211 | nodemap, |
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200 | 212 | }) |
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201 | 213 | } |
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202 | 214 | |
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203 | 215 | /// Return number of entries of the `Revlog`. |
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204 | 216 | pub fn len(&self) -> usize { |
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205 | 217 | self.index.len() |
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206 | 218 | } |
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207 | 219 | |
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208 | 220 | /// Returns `true` if the `Revlog` has zero `entries`. |
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209 | 221 | pub fn is_empty(&self) -> bool { |
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210 | 222 | self.index.is_empty() |
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211 | 223 | } |
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212 | 224 | |
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213 | 225 | /// Returns the node ID for the given revision number, if it exists in this |
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214 | 226 | /// revlog |
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215 | 227 | pub fn node_from_rev(&self, rev: Revision) -> Option<&Node> { |
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216 | 228 | if rev == NULL_REVISION { |
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217 | 229 | return Some(&NULL_NODE); |
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218 | 230 | } |
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219 | 231 | Some(self.index.get_entry(rev)?.hash()) |
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220 | 232 | } |
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221 | 233 | |
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222 | 234 | /// Return the revision number for the given node ID, if it exists in this |
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223 | 235 | /// revlog |
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224 | 236 | pub fn rev_from_node( |
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225 | 237 | &self, |
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226 | 238 | node: NodePrefix, |
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227 | 239 | ) -> Result<Revision, RevlogError> { |
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228 | 240 | if let Some(nodemap) = &self.nodemap { |
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229 | 241 | nodemap |
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230 | 242 | .find_bin(&self.index, node)? |
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231 | 243 | .ok_or(RevlogError::InvalidRevision) |
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232 | 244 | } else { |
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233 | 245 | self.rev_from_node_no_persistent_nodemap(node) |
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234 | 246 | } |
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235 | 247 | } |
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236 | 248 | |
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237 | 249 | /// Same as `rev_from_node`, without using a persistent nodemap |
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238 | 250 | /// |
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239 | 251 | /// This is used as fallback when a persistent nodemap is not present. |
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240 | 252 | /// This happens when the persistent-nodemap experimental feature is not |
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241 | 253 | /// enabled, or for small revlogs. |
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242 | 254 | fn rev_from_node_no_persistent_nodemap( |
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243 | 255 | &self, |
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244 | 256 | node: NodePrefix, |
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245 | 257 | ) -> Result<Revision, RevlogError> { |
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246 | 258 | // Linear scan of the revlog |
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247 | 259 | // TODO: consider building a non-persistent nodemap in memory to |
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248 | 260 | // optimize these cases. |
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249 | 261 | let mut found_by_prefix = None; |
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250 | 262 | for rev in (-1..self.len() as Revision).rev() { |
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251 | 263 | let candidate_node = if rev == -1 { |
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252 | 264 | NULL_NODE |
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253 | 265 | } else { |
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254 | 266 | let index_entry = |
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255 | 267 | self.index.get_entry(rev).ok_or_else(|| { |
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256 | 268 | HgError::corrupted( |
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257 | 269 | "revlog references a revision not in the index", |
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258 | 270 | ) |
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259 | 271 | })?; |
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260 | 272 | *index_entry.hash() |
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261 | 273 | }; |
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262 | 274 | if node == candidate_node { |
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263 | 275 | return Ok(rev); |
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264 | 276 | } |
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265 | 277 | if node.is_prefix_of(&candidate_node) { |
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266 | 278 | if found_by_prefix.is_some() { |
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267 | 279 | return Err(RevlogError::AmbiguousPrefix); |
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268 | 280 | } |
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269 | 281 | found_by_prefix = Some(rev) |
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270 | 282 | } |
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271 | 283 | } |
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272 | 284 | found_by_prefix.ok_or(RevlogError::InvalidRevision) |
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273 | 285 | } |
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274 | 286 | |
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275 | 287 | /// Returns whether the given revision exists in this revlog. |
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276 | 288 | pub fn has_rev(&self, rev: Revision) -> bool { |
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277 | 289 | self.index.get_entry(rev).is_some() |
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278 | 290 | } |
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279 | 291 | |
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280 | 292 | /// Return the full data associated to a revision. |
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281 | 293 | /// |
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282 | 294 | /// All entries required to build the final data out of deltas will be |
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283 | 295 | /// retrieved as needed, and the deltas will be applied to the inital |
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284 | 296 | /// snapshot to rebuild the final data. |
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285 | 297 | pub fn get_rev_data( |
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286 | 298 | &self, |
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287 | 299 | rev: Revision, |
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288 | 300 | ) -> Result<Cow<[u8]>, RevlogError> { |
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289 | 301 | if rev == NULL_REVISION { |
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290 | 302 | return Ok(Cow::Borrowed(&[])); |
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291 | 303 | }; |
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292 | 304 | Ok(self.get_entry(rev)?.data()?) |
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293 | 305 | } |
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294 | 306 | |
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295 | 307 | /// Check the hash of some given data against the recorded hash. |
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296 | 308 | pub fn check_hash( |
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297 | 309 | &self, |
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298 | 310 | p1: Revision, |
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299 | 311 | p2: Revision, |
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300 | 312 | expected: &[u8], |
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301 | 313 | data: &[u8], |
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302 | 314 | ) -> bool { |
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303 | 315 | let e1 = self.index.get_entry(p1); |
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304 | 316 | let h1 = match e1 { |
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305 | 317 | Some(ref entry) => entry.hash(), |
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306 | 318 | None => &NULL_NODE, |
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307 | 319 | }; |
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308 | 320 | let e2 = self.index.get_entry(p2); |
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309 | 321 | let h2 = match e2 { |
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310 | 322 | Some(ref entry) => entry.hash(), |
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311 | 323 | None => &NULL_NODE, |
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312 | 324 | }; |
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313 | 325 | |
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314 | 326 | hash(data, h1.as_bytes(), h2.as_bytes()) == expected |
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315 | 327 | } |
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316 | 328 | |
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317 | 329 | /// Build the full data of a revision out its snapshot |
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318 | 330 | /// and its deltas. |
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319 | 331 | fn build_data_from_deltas( |
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320 | 332 | snapshot: RevlogEntry, |
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321 | 333 | deltas: &[RevlogEntry], |
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322 | 334 | ) -> Result<Vec<u8>, HgError> { |
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323 | 335 | let snapshot = snapshot.data_chunk()?; |
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324 | 336 | let deltas = deltas |
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325 | 337 | .iter() |
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326 | 338 | .rev() |
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327 | 339 | .map(RevlogEntry::data_chunk) |
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328 | 340 | .collect::<Result<Vec<_>, _>>()?; |
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329 | 341 | let patches: Vec<_> = |
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330 | 342 | deltas.iter().map(|d| patch::PatchList::new(d)).collect(); |
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331 | 343 | let patch = patch::fold_patch_lists(&patches); |
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332 | 344 | Ok(patch.apply(&snapshot)) |
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333 | 345 | } |
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334 | 346 | |
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335 | 347 | /// Return the revlog data. |
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336 | 348 | fn data(&self) -> &[u8] { |
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337 | 349 | match &self.data_bytes { |
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338 | 350 | Some(data_bytes) => data_bytes, |
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339 | 351 | None => panic!( |
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340 | 352 | "forgot to load the data or trying to access inline data" |
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341 | 353 | ), |
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342 | 354 | } |
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343 | 355 | } |
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344 | 356 | |
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345 | 357 | pub fn make_null_entry(&self) -> RevlogEntry { |
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346 | 358 | RevlogEntry { |
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347 | 359 | revlog: self, |
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348 | 360 | rev: NULL_REVISION, |
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349 | 361 | bytes: b"", |
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350 | 362 | compressed_len: 0, |
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351 | 363 | uncompressed_len: 0, |
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352 | 364 | base_rev_or_base_of_delta_chain: None, |
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353 | 365 | p1: NULL_REVISION, |
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354 | 366 | p2: NULL_REVISION, |
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355 | 367 | flags: NULL_REVLOG_ENTRY_FLAGS, |
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356 | 368 | hash: NULL_NODE, |
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357 | 369 | } |
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358 | 370 | } |
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359 | 371 | |
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360 | 372 | /// Get an entry of the revlog. |
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361 | 373 | pub fn get_entry( |
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362 | 374 | &self, |
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363 | 375 | rev: Revision, |
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364 | 376 | ) -> Result<RevlogEntry, RevlogError> { |
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365 | 377 | if rev == NULL_REVISION { |
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366 | 378 | return Ok(self.make_null_entry()); |
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367 | 379 | } |
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368 | 380 | let index_entry = self |
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369 | 381 | .index |
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370 | 382 | .get_entry(rev) |
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371 | 383 | .ok_or(RevlogError::InvalidRevision)?; |
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372 | 384 | let start = index_entry.offset(); |
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373 | 385 | let end = start + index_entry.compressed_len() as usize; |
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374 | 386 | let data = if self.index.is_inline() { |
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375 | 387 | self.index.data(start, end) |
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376 | 388 | } else { |
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377 | 389 | &self.data()[start..end] |
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378 | 390 | }; |
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379 | 391 | let entry = RevlogEntry { |
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380 | 392 | revlog: self, |
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381 | 393 | rev, |
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382 | 394 | bytes: data, |
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383 | 395 | compressed_len: index_entry.compressed_len(), |
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384 | 396 | uncompressed_len: index_entry.uncompressed_len(), |
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385 | 397 | base_rev_or_base_of_delta_chain: if index_entry |
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386 | 398 | .base_revision_or_base_of_delta_chain() |
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387 | 399 | == rev |
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388 | 400 | { |
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389 | 401 | None |
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390 | 402 | } else { |
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391 | 403 | Some(index_entry.base_revision_or_base_of_delta_chain()) |
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392 | 404 | }, |
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393 | 405 | p1: index_entry.p1(), |
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394 | 406 | p2: index_entry.p2(), |
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395 | 407 | flags: index_entry.flags(), |
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396 | 408 | hash: *index_entry.hash(), |
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397 | 409 | }; |
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398 | 410 | Ok(entry) |
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399 | 411 | } |
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400 | 412 | |
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401 | 413 | /// when resolving internal references within revlog, any errors |
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402 | 414 | /// should be reported as corruption, instead of e.g. "invalid revision" |
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403 | 415 | fn get_entry_internal( |
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404 | 416 | &self, |
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405 | 417 | rev: Revision, |
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406 | 418 | ) -> Result<RevlogEntry, HgError> { |
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407 | 419 | self.get_entry(rev) |
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408 | 420 | .map_err(|_| corrupted(format!("revision {} out of range", rev))) |
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409 | 421 | } |
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410 | 422 | } |
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411 | 423 | |
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412 | 424 | /// The revlog entry's bytes and the necessary informations to extract |
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413 | 425 | /// the entry's data. |
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414 | 426 | #[derive(Clone)] |
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415 | 427 | pub struct RevlogEntry<'revlog> { |
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416 | 428 | revlog: &'revlog Revlog, |
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417 | 429 | rev: Revision, |
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418 | 430 | bytes: &'revlog [u8], |
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419 | 431 | compressed_len: u32, |
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420 | 432 | uncompressed_len: i32, |
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421 | 433 | base_rev_or_base_of_delta_chain: Option<Revision>, |
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422 | 434 | p1: Revision, |
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423 | 435 | p2: Revision, |
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424 | 436 | flags: u16, |
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425 | 437 | hash: Node, |
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426 | 438 | } |
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427 | 439 | |
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428 | 440 | thread_local! { |
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429 | 441 | // seems fine to [unwrap] here: this can only fail due to memory allocation |
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430 | 442 | // failing, and it's normal for that to cause panic. |
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431 | 443 | static ZSTD_DECODER : RefCell<zstd::bulk::Decompressor<'static>> = |
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432 | 444 | RefCell::new(zstd::bulk::Decompressor::new().ok().unwrap()); |
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433 | 445 | } |
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434 | 446 | |
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435 | 447 | fn zstd_decompress_to_buffer( |
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436 | 448 | bytes: &[u8], |
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437 | 449 | buf: &mut Vec<u8>, |
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438 | 450 | ) -> Result<usize, std::io::Error> { |
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439 | 451 | ZSTD_DECODER |
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440 | 452 | .with(|decoder| decoder.borrow_mut().decompress_to_buffer(bytes, buf)) |
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441 | 453 | } |
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442 | 454 | |
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443 | 455 | impl<'revlog> RevlogEntry<'revlog> { |
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444 | 456 | pub fn revision(&self) -> Revision { |
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445 | 457 | self.rev |
|
446 | 458 | } |
|
447 | 459 | |
|
448 | 460 | pub fn node(&self) -> &Node { |
|
449 | 461 | &self.hash |
|
450 | 462 | } |
|
451 | 463 | |
|
452 | 464 | pub fn uncompressed_len(&self) -> Option<u32> { |
|
453 | 465 | u32::try_from(self.uncompressed_len).ok() |
|
454 | 466 | } |
|
455 | 467 | |
|
456 | 468 | pub fn has_p1(&self) -> bool { |
|
457 | 469 | self.p1 != NULL_REVISION |
|
458 | 470 | } |
|
459 | 471 | |
|
460 | 472 | pub fn p1_entry( |
|
461 | 473 | &self, |
|
462 | 474 | ) -> Result<Option<RevlogEntry<'revlog>>, RevlogError> { |
|
463 | 475 | if self.p1 == NULL_REVISION { |
|
464 | 476 | Ok(None) |
|
465 | 477 | } else { |
|
466 | 478 | Ok(Some(self.revlog.get_entry(self.p1)?)) |
|
467 | 479 | } |
|
468 | 480 | } |
|
469 | 481 | |
|
470 | 482 | pub fn p2_entry( |
|
471 | 483 | &self, |
|
472 | 484 | ) -> Result<Option<RevlogEntry<'revlog>>, RevlogError> { |
|
473 | 485 | if self.p2 == NULL_REVISION { |
|
474 | 486 | Ok(None) |
|
475 | 487 | } else { |
|
476 | 488 | Ok(Some(self.revlog.get_entry(self.p2)?)) |
|
477 | 489 | } |
|
478 | 490 | } |
|
479 | 491 | |
|
480 | 492 | pub fn p1(&self) -> Option<Revision> { |
|
481 | 493 | if self.p1 == NULL_REVISION { |
|
482 | 494 | None |
|
483 | 495 | } else { |
|
484 | 496 | Some(self.p1) |
|
485 | 497 | } |
|
486 | 498 | } |
|
487 | 499 | |
|
488 | 500 | pub fn p2(&self) -> Option<Revision> { |
|
489 | 501 | if self.p2 == NULL_REVISION { |
|
490 | 502 | None |
|
491 | 503 | } else { |
|
492 | 504 | Some(self.p2) |
|
493 | 505 | } |
|
494 | 506 | } |
|
495 | 507 | |
|
496 | 508 | pub fn is_censored(&self) -> bool { |
|
497 | 509 | (self.flags & REVISION_FLAG_CENSORED) != 0 |
|
498 | 510 | } |
|
499 | 511 | |
|
500 | 512 | pub fn has_length_affecting_flag_processor(&self) -> bool { |
|
501 | 513 | // Relevant Python code: revlog.size() |
|
502 | 514 | // note: ELLIPSIS is known to not change the content |
|
503 | 515 | (self.flags & (REVIDX_KNOWN_FLAGS ^ REVISION_FLAG_ELLIPSIS)) != 0 |
|
504 | 516 | } |
|
505 | 517 | |
|
506 | 518 | /// The data for this entry, after resolving deltas if any. |
|
507 | 519 | pub fn rawdata(&self) -> Result<Cow<'revlog, [u8]>, HgError> { |
|
508 | 520 | let mut entry = self.clone(); |
|
509 | 521 | let mut delta_chain = vec![]; |
|
510 | 522 | |
|
511 | 523 | // The meaning of `base_rev_or_base_of_delta_chain` depends on |
|
512 | 524 | // generaldelta. See the doc on `ENTRY_DELTA_BASE` in |
|
513 | 525 | // `mercurial/revlogutils/constants.py` and the code in |
|
514 | 526 | // [_chaininfo] and in [index_deltachain]. |
|
515 | 527 | let uses_generaldelta = self.revlog.index.uses_generaldelta(); |
|
516 | 528 | while let Some(base_rev) = entry.base_rev_or_base_of_delta_chain { |
|
517 | 529 | let base_rev = if uses_generaldelta { |
|
518 | 530 | base_rev |
|
519 | 531 | } else { |
|
520 | 532 | entry.rev - 1 |
|
521 | 533 | }; |
|
522 | 534 | delta_chain.push(entry); |
|
523 | 535 | entry = self.revlog.get_entry_internal(base_rev)?; |
|
524 | 536 | } |
|
525 | 537 | |
|
526 | 538 | let data = if delta_chain.is_empty() { |
|
527 | 539 | entry.data_chunk()? |
|
528 | 540 | } else { |
|
529 | 541 | Revlog::build_data_from_deltas(entry, &delta_chain)?.into() |
|
530 | 542 | }; |
|
531 | 543 | |
|
532 | 544 | Ok(data) |
|
533 | 545 | } |
|
534 | 546 | |
|
535 | 547 | fn check_data( |
|
536 | 548 | &self, |
|
537 | 549 | data: Cow<'revlog, [u8]>, |
|
538 | 550 | ) -> Result<Cow<'revlog, [u8]>, HgError> { |
|
539 | 551 | if self.revlog.check_hash( |
|
540 | 552 | self.p1, |
|
541 | 553 | self.p2, |
|
542 | 554 | self.hash.as_bytes(), |
|
543 | 555 | &data, |
|
544 | 556 | ) { |
|
545 | 557 | Ok(data) |
|
546 | 558 | } else { |
|
547 | 559 | if (self.flags & REVISION_FLAG_ELLIPSIS) != 0 { |
|
548 | 560 | return Err(HgError::unsupported( |
|
549 | 561 | "ellipsis revisions are not supported by rhg", |
|
550 | 562 | )); |
|
551 | 563 | } |
|
552 | 564 | Err(corrupted(format!( |
|
553 | 565 | "hash check failed for revision {}", |
|
554 | 566 | self.rev |
|
555 | 567 | ))) |
|
556 | 568 | } |
|
557 | 569 | } |
|
558 | 570 | |
|
559 | 571 | pub fn data(&self) -> Result<Cow<'revlog, [u8]>, HgError> { |
|
560 | 572 | let data = self.rawdata()?; |
|
561 | 573 | if self.rev == NULL_REVISION { |
|
562 | 574 | return Ok(data); |
|
563 | 575 | } |
|
564 | 576 | if self.is_censored() { |
|
565 | 577 | return Err(HgError::CensoredNodeError); |
|
566 | 578 | } |
|
567 | 579 | self.check_data(data) |
|
568 | 580 | } |
|
569 | 581 | |
|
570 | 582 | /// Extract the data contained in the entry. |
|
571 | 583 | /// This may be a delta. (See `is_delta`.) |
|
572 | 584 | fn data_chunk(&self) -> Result<Cow<'revlog, [u8]>, HgError> { |
|
573 | 585 | if self.bytes.is_empty() { |
|
574 | 586 | return Ok(Cow::Borrowed(&[])); |
|
575 | 587 | } |
|
576 | 588 | match self.bytes[0] { |
|
577 | 589 | // Revision data is the entirety of the entry, including this |
|
578 | 590 | // header. |
|
579 | 591 | b'\0' => Ok(Cow::Borrowed(self.bytes)), |
|
580 | 592 | // Raw revision data follows. |
|
581 | 593 | b'u' => Ok(Cow::Borrowed(&self.bytes[1..])), |
|
582 | 594 | // zlib (RFC 1950) data. |
|
583 | 595 | b'x' => Ok(Cow::Owned(self.uncompressed_zlib_data()?)), |
|
584 | 596 | // zstd data. |
|
585 | 597 | b'\x28' => Ok(Cow::Owned(self.uncompressed_zstd_data()?)), |
|
586 | 598 | // A proper new format should have had a repo/store requirement. |
|
587 | 599 | format_type => Err(corrupted(format!( |
|
588 | 600 | "unknown compression header '{}'", |
|
589 | 601 | format_type |
|
590 | 602 | ))), |
|
591 | 603 | } |
|
592 | 604 | } |
|
593 | 605 | |
|
594 | 606 | fn uncompressed_zlib_data(&self) -> Result<Vec<u8>, HgError> { |
|
595 | 607 | let mut decoder = ZlibDecoder::new(self.bytes); |
|
596 | 608 | if self.is_delta() { |
|
597 | 609 | let mut buf = Vec::with_capacity(self.compressed_len as usize); |
|
598 | 610 | decoder |
|
599 | 611 | .read_to_end(&mut buf) |
|
600 | 612 | .map_err(|e| corrupted(e.to_string()))?; |
|
601 | 613 | Ok(buf) |
|
602 | 614 | } else { |
|
603 | 615 | let cap = self.uncompressed_len.max(0) as usize; |
|
604 | 616 | let mut buf = vec![0; cap]; |
|
605 | 617 | decoder |
|
606 | 618 | .read_exact(&mut buf) |
|
607 | 619 | .map_err(|e| corrupted(e.to_string()))?; |
|
608 | 620 | Ok(buf) |
|
609 | 621 | } |
|
610 | 622 | } |
|
611 | 623 | |
|
612 | 624 | fn uncompressed_zstd_data(&self) -> Result<Vec<u8>, HgError> { |
|
613 | 625 | let cap = self.uncompressed_len.max(0) as usize; |
|
614 | 626 | if self.is_delta() { |
|
615 | 627 | // [cap] is usually an over-estimate of the space needed because |
|
616 | 628 | // it's the length of delta-decoded data, but we're interested |
|
617 | 629 | // in the size of the delta. |
|
618 | 630 | // This means we have to [shrink_to_fit] to avoid holding on |
|
619 | 631 | // to a large chunk of memory, but it also means we must have a |
|
620 | 632 | // fallback branch, for the case when the delta is longer than |
|
621 | 633 | // the original data (surprisingly, this does happen in practice) |
|
622 | 634 | let mut buf = Vec::with_capacity(cap); |
|
623 | 635 | match zstd_decompress_to_buffer(self.bytes, &mut buf) { |
|
624 | 636 | Ok(_) => buf.shrink_to_fit(), |
|
625 | 637 | Err(_) => { |
|
626 | 638 | buf.clear(); |
|
627 | 639 | zstd::stream::copy_decode(self.bytes, &mut buf) |
|
628 | 640 | .map_err(|e| corrupted(e.to_string()))?; |
|
629 | 641 | } |
|
630 | 642 | }; |
|
631 | 643 | Ok(buf) |
|
632 | 644 | } else { |
|
633 | 645 | let mut buf = Vec::with_capacity(cap); |
|
634 | 646 | let len = zstd_decompress_to_buffer(self.bytes, &mut buf) |
|
635 | 647 | .map_err(|e| corrupted(e.to_string()))?; |
|
636 | 648 | if len != self.uncompressed_len as usize { |
|
637 | 649 | Err(corrupted("uncompressed length does not match")) |
|
638 | 650 | } else { |
|
639 | 651 | Ok(buf) |
|
640 | 652 | } |
|
641 | 653 | } |
|
642 | 654 | } |
|
643 | 655 | |
|
644 | 656 | /// Tell if the entry is a snapshot or a delta |
|
645 | 657 | /// (influences on decompression). |
|
646 | 658 | fn is_delta(&self) -> bool { |
|
647 | 659 | self.base_rev_or_base_of_delta_chain.is_some() |
|
648 | 660 | } |
|
649 | 661 | } |
|
650 | 662 | |
|
651 | 663 | /// Calculate the hash of a revision given its data and its parents. |
|
652 | 664 | fn hash( |
|
653 | 665 | data: &[u8], |
|
654 | 666 | p1_hash: &[u8], |
|
655 | 667 | p2_hash: &[u8], |
|
656 | 668 | ) -> [u8; NODE_BYTES_LENGTH] { |
|
657 | 669 | let mut hasher = Sha1::new(); |
|
658 | 670 | let (a, b) = (p1_hash, p2_hash); |
|
659 | 671 | if a > b { |
|
660 | 672 | hasher.update(b); |
|
661 | 673 | hasher.update(a); |
|
662 | 674 | } else { |
|
663 | 675 | hasher.update(a); |
|
664 | 676 | hasher.update(b); |
|
665 | 677 | } |
|
666 | 678 | hasher.update(data); |
|
667 | 679 | *hasher.finalize().as_ref() |
|
668 | 680 | } |
|
669 | 681 | |
|
670 | 682 | #[cfg(test)] |
|
671 | 683 | mod tests { |
|
672 | 684 | use super::*; |
|
673 | 685 | use crate::index::{IndexEntryBuilder, INDEX_ENTRY_SIZE}; |
|
674 | 686 | use itertools::Itertools; |
|
675 | 687 | |
|
676 | 688 | #[test] |
|
677 | 689 | fn test_empty() { |
|
678 | 690 | let temp = tempfile::tempdir().unwrap(); |
|
679 | 691 | let vfs = Vfs { base: temp.path() }; |
|
680 | 692 | std::fs::write(temp.path().join("foo.i"), b"").unwrap(); |
|
681 | 693 | let revlog = Revlog::open(&vfs, "foo.i", None, false).unwrap(); |
|
682 | 694 | assert!(revlog.is_empty()); |
|
683 | 695 | assert_eq!(revlog.len(), 0); |
|
684 | 696 | assert!(revlog.get_entry(0).is_err()); |
|
685 | 697 | assert!(!revlog.has_rev(0)); |
|
686 | 698 | assert_eq!( |
|
687 | 699 | revlog.rev_from_node(NULL_NODE.into()).unwrap(), |
|
688 | 700 | NULL_REVISION |
|
689 | 701 | ); |
|
690 | 702 | let null_entry = revlog.get_entry(NULL_REVISION).ok().unwrap(); |
|
691 | 703 | assert_eq!(null_entry.revision(), NULL_REVISION); |
|
692 | 704 | assert!(null_entry.data().unwrap().is_empty()); |
|
693 | 705 | } |
|
694 | 706 | |
|
695 | 707 | #[test] |
|
696 | 708 | fn test_inline() { |
|
697 | 709 | let temp = tempfile::tempdir().unwrap(); |
|
698 | 710 | let vfs = Vfs { base: temp.path() }; |
|
699 | 711 | let node0 = Node::from_hex("2ed2a3912a0b24502043eae84ee4b279c18b90dd") |
|
700 | 712 | .unwrap(); |
|
701 | 713 | let node1 = Node::from_hex("b004912a8510032a0350a74daa2803dadfb00e12") |
|
702 | 714 | .unwrap(); |
|
703 | 715 | let node2 = Node::from_hex("dd6ad206e907be60927b5a3117b97dffb2590582") |
|
704 | 716 | .unwrap(); |
|
705 | 717 | let entry0_bytes = IndexEntryBuilder::new() |
|
706 | 718 | .is_first(true) |
|
707 | 719 | .with_version(1) |
|
708 | 720 | .with_inline(true) |
|
709 | 721 | .with_offset(INDEX_ENTRY_SIZE) |
|
710 | 722 | .with_node(node0) |
|
711 | 723 | .build(); |
|
712 | 724 | let entry1_bytes = IndexEntryBuilder::new() |
|
713 | 725 | .with_offset(INDEX_ENTRY_SIZE) |
|
714 | 726 | .with_node(node1) |
|
715 | 727 | .build(); |
|
716 | 728 | let entry2_bytes = IndexEntryBuilder::new() |
|
717 | 729 | .with_offset(INDEX_ENTRY_SIZE) |
|
718 | 730 | .with_p1(0) |
|
719 | 731 | .with_p2(1) |
|
720 | 732 | .with_node(node2) |
|
721 | 733 | .build(); |
|
722 | 734 | let contents = vec![entry0_bytes, entry1_bytes, entry2_bytes] |
|
723 | 735 | .into_iter() |
|
724 | 736 | .flatten() |
|
725 | 737 | .collect_vec(); |
|
726 | 738 | std::fs::write(temp.path().join("foo.i"), contents).unwrap(); |
|
727 | 739 | let revlog = Revlog::open(&vfs, "foo.i", None, false).unwrap(); |
|
728 | 740 | |
|
729 | 741 | let entry0 = revlog.get_entry(0).ok().unwrap(); |
|
730 | 742 | assert_eq!(entry0.revision(), 0); |
|
731 | 743 | assert_eq!(*entry0.node(), node0); |
|
732 | 744 | assert!(!entry0.has_p1()); |
|
733 | 745 | assert_eq!(entry0.p1(), None); |
|
734 | 746 | assert_eq!(entry0.p2(), None); |
|
735 | 747 | let p1_entry = entry0.p1_entry().unwrap(); |
|
736 | 748 | assert!(p1_entry.is_none()); |
|
737 | 749 | let p2_entry = entry0.p2_entry().unwrap(); |
|
738 | 750 | assert!(p2_entry.is_none()); |
|
739 | 751 | |
|
740 | 752 | let entry1 = revlog.get_entry(1).ok().unwrap(); |
|
741 | 753 | assert_eq!(entry1.revision(), 1); |
|
742 | 754 | assert_eq!(*entry1.node(), node1); |
|
743 | 755 | assert!(!entry1.has_p1()); |
|
744 | 756 | assert_eq!(entry1.p1(), None); |
|
745 | 757 | assert_eq!(entry1.p2(), None); |
|
746 | 758 | let p1_entry = entry1.p1_entry().unwrap(); |
|
747 | 759 | assert!(p1_entry.is_none()); |
|
748 | 760 | let p2_entry = entry1.p2_entry().unwrap(); |
|
749 | 761 | assert!(p2_entry.is_none()); |
|
750 | 762 | |
|
751 | 763 | let entry2 = revlog.get_entry(2).ok().unwrap(); |
|
752 | 764 | assert_eq!(entry2.revision(), 2); |
|
753 | 765 | assert_eq!(*entry2.node(), node2); |
|
754 | 766 | assert!(entry2.has_p1()); |
|
755 | 767 | assert_eq!(entry2.p1(), Some(0)); |
|
756 | 768 | assert_eq!(entry2.p2(), Some(1)); |
|
757 | 769 | let p1_entry = entry2.p1_entry().unwrap(); |
|
758 | 770 | assert!(p1_entry.is_some()); |
|
759 | 771 | assert_eq!(p1_entry.unwrap().revision(), 0); |
|
760 | 772 | let p2_entry = entry2.p2_entry().unwrap(); |
|
761 | 773 | assert!(p2_entry.is_some()); |
|
762 | 774 | assert_eq!(p2_entry.unwrap().revision(), 1); |
|
763 | 775 | } |
|
764 | 776 | |
|
765 | 777 | #[test] |
|
766 | 778 | fn test_nodemap() { |
|
767 | 779 | let temp = tempfile::tempdir().unwrap(); |
|
768 | 780 | let vfs = Vfs { base: temp.path() }; |
|
769 | 781 | |
|
770 | 782 | // building a revlog with a forced Node starting with zeros |
|
771 | 783 | // This is a corruption, but it does not preclude using the nodemap |
|
772 | 784 | // if we don't try and access the data |
|
773 | 785 | let node0 = Node::from_hex("00d2a3912a0b24502043eae84ee4b279c18b90dd") |
|
774 | 786 | .unwrap(); |
|
775 | 787 | let node1 = Node::from_hex("b004912a8510032a0350a74daa2803dadfb00e12") |
|
776 | 788 | .unwrap(); |
|
777 | 789 | let entry0_bytes = IndexEntryBuilder::new() |
|
778 | 790 | .is_first(true) |
|
779 | 791 | .with_version(1) |
|
780 | 792 | .with_inline(true) |
|
781 | 793 | .with_offset(INDEX_ENTRY_SIZE) |
|
782 | 794 | .with_node(node0) |
|
783 | 795 | .build(); |
|
784 | 796 | let entry1_bytes = IndexEntryBuilder::new() |
|
785 | 797 | .with_offset(INDEX_ENTRY_SIZE) |
|
786 | 798 | .with_node(node1) |
|
787 | 799 | .build(); |
|
788 | 800 | let contents = vec![entry0_bytes, entry1_bytes] |
|
789 | 801 | .into_iter() |
|
790 | 802 | .flatten() |
|
791 | 803 | .collect_vec(); |
|
792 | 804 | std::fs::write(temp.path().join("foo.i"), contents).unwrap(); |
|
793 | let revlog = Revlog::open(&vfs, "foo.i", None, false).unwrap(); | |
|
805 | ||
|
806 | let mut idx = nodemap::tests::TestNtIndex::new(); | |
|
807 | idx.insert_node(0, node0).unwrap(); | |
|
808 | idx.insert_node(1, node1).unwrap(); | |
|
809 | ||
|
810 | let revlog = | |
|
811 | Revlog::open_gen(&vfs, "foo.i", None, true, Some(idx.nt)).unwrap(); | |
|
794 | 812 | |
|
795 | 813 | // accessing the data shows the corruption |
|
796 | 814 | revlog.get_entry(0).unwrap().data().unwrap_err(); |
|
797 | 815 | |
|
798 | 816 | assert_eq!(revlog.rev_from_node(NULL_NODE.into()).unwrap(), -1); |
|
799 | 817 | assert_eq!(revlog.rev_from_node(node0.into()).unwrap(), 0); |
|
800 | 818 | assert_eq!(revlog.rev_from_node(node1.into()).unwrap(), 1); |
|
801 | 819 | assert_eq!( |
|
802 | 820 | revlog |
|
803 | 821 | .rev_from_node(NodePrefix::from_hex("000").unwrap()) |
|
804 | 822 | .unwrap(), |
|
805 | 823 | -1 |
|
806 | 824 | ); |
|
807 | 825 | assert_eq!( |
|
808 | 826 | revlog |
|
809 | 827 | .rev_from_node(NodePrefix::from_hex("b00").unwrap()) |
|
810 | 828 | .unwrap(), |
|
811 | 829 | 1 |
|
812 | 830 | ); |
|
813 | 831 | // RevlogError does not implement PartialEq |
|
814 | 832 | // (ultimately because io::Error does not) |
|
815 | 833 | match revlog |
|
816 | 834 | .rev_from_node(NodePrefix::from_hex("00").unwrap()) |
|
817 | 835 | .expect_err("Expected to give AmbiguousPrefix error") |
|
818 | 836 | { |
|
819 | 837 | RevlogError::AmbiguousPrefix => (), |
|
820 | 838 | e => { |
|
821 | 839 | panic!("Got another error than AmbiguousPrefix: {:?}", e); |
|
822 | 840 | } |
|
823 | 841 | }; |
|
824 | 842 | } |
|
825 | 843 | } |
@@ -1,1067 +1,1074 b'' | |||
|
1 | 1 | // Copyright 2018-2020 Georges Racinet <georges.racinet@octobus.net> |
|
2 | 2 | // and Mercurial contributors |
|
3 | 3 | // |
|
4 | 4 | // This software may be used and distributed according to the terms of the |
|
5 | 5 | // GNU General Public License version 2 or any later version. |
|
6 | 6 | //! Indexing facilities for fast retrieval of `Revision` from `Node` |
|
7 | 7 | //! |
|
8 | 8 | //! This provides a variation on the 16-ary radix tree that is |
|
9 | 9 | //! provided as "nodetree" in revlog.c, ready for append-only persistence |
|
10 | 10 | //! on disk. |
|
11 | 11 | //! |
|
12 | 12 | //! Following existing implicit conventions, the "nodemap" terminology |
|
13 | 13 | //! is used in a more abstract context. |
|
14 | 14 | |
|
15 | 15 | use super::{ |
|
16 | 16 | node::NULL_NODE, Node, NodePrefix, Revision, RevlogIndex, NULL_REVISION, |
|
17 | 17 | }; |
|
18 | 18 | |
|
19 | 19 | use bytes_cast::{unaligned, BytesCast}; |
|
20 | 20 | use std::cmp::max; |
|
21 | 21 | use std::fmt; |
|
22 | 22 | use std::mem::{self, align_of, size_of}; |
|
23 | 23 | use std::ops::Deref; |
|
24 | 24 | use std::ops::Index; |
|
25 | 25 | |
|
26 | 26 | #[derive(Debug, PartialEq)] |
|
27 | 27 | pub enum NodeMapError { |
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28 | 28 | /// A `NodePrefix` matches several [`Revision`]s. |
|
29 | 29 | /// |
|
30 | 30 | /// This can be returned by methods meant for (at most) one match. |
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31 | 31 | MultipleResults, |
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32 | 32 | /// A `Revision` stored in the nodemap could not be found in the index |
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33 | 33 | RevisionNotInIndex(Revision), |
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34 | 34 | } |
|
35 | 35 | |
|
36 | 36 | /// Mapping system from Mercurial nodes to revision numbers. |
|
37 | 37 | /// |
|
38 | 38 | /// ## `RevlogIndex` and `NodeMap` |
|
39 | 39 | /// |
|
40 | 40 | /// One way to think about their relationship is that |
|
41 | 41 | /// the `NodeMap` is a prefix-oriented reverse index of the [`Node`] |
|
42 | 42 | /// information carried by a [`RevlogIndex`]. |
|
43 | 43 | /// |
|
44 | 44 | /// Many of the methods in this trait take a `RevlogIndex` argument |
|
45 | 45 | /// which is used for validation of their results. This index must naturally |
|
46 | 46 | /// be the one the `NodeMap` is about, and it must be consistent. |
|
47 | 47 | /// |
|
48 | 48 | /// Notably, the `NodeMap` must not store |
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49 | 49 | /// information about more `Revision` values than there are in the index. |
|
50 | 50 | /// In these methods, an encountered `Revision` is not in the index, a |
|
51 | 51 | /// [RevisionNotInIndex](NodeMapError) error is returned. |
|
52 | 52 | /// |
|
53 | 53 | /// In insert operations, the rule is thus that the `NodeMap` must always |
|
54 | 54 | /// be updated after the `RevlogIndex` it is about. |
|
55 | 55 | pub trait NodeMap { |
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56 | 56 | /// Find the unique `Revision` having the given `Node` |
|
57 | 57 | /// |
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58 | 58 | /// If no Revision matches the given `Node`, `Ok(None)` is returned. |
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59 | 59 | fn find_node( |
|
60 | 60 | &self, |
|
61 | 61 | index: &impl RevlogIndex, |
|
62 | 62 | node: &Node, |
|
63 | 63 | ) -> Result<Option<Revision>, NodeMapError> { |
|
64 | 64 | self.find_bin(index, node.into()) |
|
65 | 65 | } |
|
66 | 66 | |
|
67 | 67 | /// Find the unique Revision whose `Node` starts with a given binary prefix |
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68 | 68 | /// |
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69 | 69 | /// If no Revision matches the given prefix, `Ok(None)` is returned. |
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70 | 70 | /// |
|
71 | 71 | /// If several Revisions match the given prefix, a |
|
72 | 72 | /// [MultipleResults](NodeMapError) error is returned. |
|
73 | 73 | fn find_bin( |
|
74 | 74 | &self, |
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75 | 75 | idx: &impl RevlogIndex, |
|
76 | 76 | prefix: NodePrefix, |
|
77 | 77 | ) -> Result<Option<Revision>, NodeMapError>; |
|
78 | 78 | |
|
79 | 79 | /// Give the size of the shortest node prefix that determines |
|
80 | 80 | /// the revision uniquely. |
|
81 | 81 | /// |
|
82 | 82 | /// From a binary node prefix, if it is matched in the node map, this |
|
83 | 83 | /// returns the number of hexadecimal digits that would had sufficed |
|
84 | 84 | /// to find the revision uniquely. |
|
85 | 85 | /// |
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86 | 86 | /// Returns `None` if no [`Revision`] could be found for the prefix. |
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87 | 87 | /// |
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88 | 88 | /// If several Revisions match the given prefix, a |
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89 | 89 | /// [MultipleResults](NodeMapError) error is returned. |
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90 | 90 | fn unique_prefix_len_bin( |
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91 | 91 | &self, |
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92 | 92 | idx: &impl RevlogIndex, |
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93 | 93 | node_prefix: NodePrefix, |
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94 | 94 | ) -> Result<Option<usize>, NodeMapError>; |
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95 | 95 | |
|
96 | 96 | /// Same as [unique_prefix_len_bin](Self::unique_prefix_len_bin), with |
|
97 | 97 | /// a full [`Node`] as input |
|
98 | 98 | fn unique_prefix_len_node( |
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99 | 99 | &self, |
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100 | 100 | idx: &impl RevlogIndex, |
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101 | 101 | node: &Node, |
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102 | 102 | ) -> Result<Option<usize>, NodeMapError> { |
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103 | 103 | self.unique_prefix_len_bin(idx, node.into()) |
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104 | 104 | } |
|
105 | 105 | } |
|
106 | 106 | |
|
107 | 107 | pub trait MutableNodeMap: NodeMap { |
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108 | 108 | fn insert<I: RevlogIndex>( |
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109 | 109 | &mut self, |
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110 | 110 | index: &I, |
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111 | 111 | node: &Node, |
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112 | 112 | rev: Revision, |
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113 | 113 | ) -> Result<(), NodeMapError>; |
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114 | 114 | } |
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115 | 115 | |
|
116 | 116 | /// Low level NodeTree [`Block`] elements |
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117 | 117 | /// |
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118 | 118 | /// These are exactly as for instance on persistent storage. |
|
119 | 119 | type RawElement = unaligned::I32Be; |
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120 | 120 | |
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121 | 121 | /// High level representation of values in NodeTree |
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122 | 122 | /// [`Blocks`](struct.Block.html) |
|
123 | 123 | /// |
|
124 | 124 | /// This is the high level representation that most algorithms should |
|
125 | 125 | /// use. |
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126 | 126 | #[derive(Clone, Debug, Eq, PartialEq)] |
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127 | 127 | enum Element { |
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128 | 128 | Rev(Revision), |
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129 | 129 | Block(usize), |
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130 | 130 | None, |
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131 | 131 | } |
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132 | 132 | |
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133 | 133 | impl From<RawElement> for Element { |
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134 | 134 | /// Conversion from low level representation, after endianness conversion. |
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135 | 135 | /// |
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136 | 136 | /// See [`Block`](struct.Block.html) for explanation about the encoding. |
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137 | 137 | fn from(raw: RawElement) -> Element { |
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138 | 138 | let int = raw.get(); |
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139 | 139 | if int >= 0 { |
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140 | 140 | Element::Block(int as usize) |
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141 | 141 | } else if int == -1 { |
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142 | 142 | Element::None |
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143 | 143 | } else { |
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144 | 144 | Element::Rev(-int - 2) |
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145 | 145 | } |
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146 | 146 | } |
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147 | 147 | } |
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148 | 148 | |
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149 | 149 | impl From<Element> for RawElement { |
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150 | 150 | fn from(element: Element) -> RawElement { |
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151 | 151 | RawElement::from(match element { |
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152 | 152 | Element::None => 0, |
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153 | 153 | Element::Block(i) => i as i32, |
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154 | 154 | Element::Rev(rev) => -rev - 2, |
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155 | 155 | }) |
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156 | 156 | } |
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157 | 157 | } |
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158 | 158 | |
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159 | 159 | const ELEMENTS_PER_BLOCK: usize = 16; // number of different values in a nybble |
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160 | 160 | |
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161 | 161 | /// A logical block of the [`NodeTree`], packed with a fixed size. |
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162 | 162 | /// |
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163 | 163 | /// These are always used in container types implementing `Index<Block>`, |
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164 | 164 | /// such as `&Block` |
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165 | 165 | /// |
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166 | 166 | /// As an array of integers, its ith element encodes that the |
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167 | 167 | /// ith potential edge from the block, representing the ith hexadecimal digit |
|
168 | 168 | /// (nybble) `i` is either: |
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169 | 169 | /// |
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170 | 170 | /// - absent (value -1) |
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171 | 171 | /// - another `Block` in the same indexable container (value β₯ 0) |
|
172 | 172 | /// - a [`Revision`] leaf (value β€ -2) |
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173 | 173 | /// |
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174 | 174 | /// Endianness has to be fixed for consistency on shared storage across |
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175 | 175 | /// different architectures. |
|
176 | 176 | /// |
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177 | 177 | /// A key difference with the C `nodetree` is that we need to be |
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178 | 178 | /// able to represent the [`Block`] at index 0, hence -1 is the empty marker |
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179 | 179 | /// rather than 0 and the [`Revision`] range upper limit of -2 instead of -1. |
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180 | 180 | /// |
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181 | 181 | /// Another related difference is that `NULL_REVISION` (-1) is not |
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182 | 182 | /// represented at all, because we want an immutable empty nodetree |
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183 | 183 | /// to be valid. |
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184 | 184 | #[derive(Copy, Clone, BytesCast, PartialEq)] |
|
185 | 185 | #[repr(transparent)] |
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186 | 186 | pub struct Block([RawElement; ELEMENTS_PER_BLOCK]); |
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187 | 187 | |
|
188 | 188 | impl Block { |
|
189 | 189 | fn new() -> Self { |
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190 | 190 | let absent_node = RawElement::from(-1); |
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191 | 191 | Block([absent_node; ELEMENTS_PER_BLOCK]) |
|
192 | 192 | } |
|
193 | 193 | |
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194 | 194 | fn get(&self, nybble: u8) -> Element { |
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195 | 195 | self.0[nybble as usize].into() |
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196 | 196 | } |
|
197 | 197 | |
|
198 | 198 | fn set(&mut self, nybble: u8, element: Element) { |
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199 | 199 | self.0[nybble as usize] = element.into() |
|
200 | 200 | } |
|
201 | 201 | } |
|
202 | 202 | |
|
203 | 203 | impl fmt::Debug for Block { |
|
204 | 204 | /// sparse representation for testing and debugging purposes |
|
205 | 205 | fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
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206 | 206 | f.debug_map() |
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207 | 207 | .entries((0..16).filter_map(|i| match self.get(i) { |
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208 | 208 | Element::None => None, |
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209 | 209 | element => Some((i, element)), |
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210 | 210 | })) |
|
211 | 211 | .finish() |
|
212 | 212 | } |
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213 | 213 | } |
|
214 | 214 | |
|
215 | 215 | /// A mutable 16-radix tree with the root block logically at the end |
|
216 | 216 | /// |
|
217 | 217 | /// Because of the append only nature of our node trees, we need to |
|
218 | 218 | /// keep the original untouched and store new blocks separately. |
|
219 | 219 | /// |
|
220 | 220 | /// The mutable root [`Block`] is kept apart so that we don't have to rebump |
|
221 | 221 | /// it on each insertion. |
|
222 | 222 | pub struct NodeTree { |
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223 | 223 | readonly: Box<dyn Deref<Target = [Block]> + Send>, |
|
224 | 224 | growable: Vec<Block>, |
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225 | 225 | root: Block, |
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226 | 226 | masked_inner_blocks: usize, |
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227 | 227 | } |
|
228 | 228 | |
|
229 | 229 | impl Index<usize> for NodeTree { |
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230 | 230 | type Output = Block; |
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231 | 231 | |
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232 | 232 | fn index(&self, i: usize) -> &Block { |
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233 | 233 | let ro_len = self.readonly.len(); |
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234 | 234 | if i < ro_len { |
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235 | 235 | &self.readonly[i] |
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236 | 236 | } else if i == ro_len + self.growable.len() { |
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237 | 237 | &self.root |
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238 | 238 | } else { |
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239 | 239 | &self.growable[i - ro_len] |
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240 | 240 | } |
|
241 | 241 | } |
|
242 | 242 | } |
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243 | 243 | |
|
244 | 244 | /// Return `None` unless the [`Node`] for `rev` has given prefix in `idx`. |
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245 | 245 | fn has_prefix_or_none( |
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246 | 246 | idx: &impl RevlogIndex, |
|
247 | 247 | prefix: NodePrefix, |
|
248 | 248 | rev: Revision, |
|
249 | 249 | ) -> Result<Option<Revision>, NodeMapError> { |
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250 | 250 | idx.node(rev) |
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251 | 251 | .ok_or(NodeMapError::RevisionNotInIndex(rev)) |
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252 | 252 | .map(|node| { |
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253 | 253 | if prefix.is_prefix_of(node) { |
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254 | 254 | Some(rev) |
|
255 | 255 | } else { |
|
256 | 256 | None |
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257 | 257 | } |
|
258 | 258 | }) |
|
259 | 259 | } |
|
260 | 260 | |
|
261 | 261 | /// validate that the candidate's node starts indeed with given prefix, |
|
262 | 262 | /// and treat ambiguities related to [`NULL_REVISION`]. |
|
263 | 263 | /// |
|
264 | 264 | /// From the data in the NodeTree, one can only conclude that some |
|
265 | 265 | /// revision is the only one for a *subprefix* of the one being looked up. |
|
266 | 266 | fn validate_candidate( |
|
267 | 267 | idx: &impl RevlogIndex, |
|
268 | 268 | prefix: NodePrefix, |
|
269 | 269 | candidate: (Option<Revision>, usize), |
|
270 | 270 | ) -> Result<(Option<Revision>, usize), NodeMapError> { |
|
271 | 271 | let (rev, steps) = candidate; |
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272 | 272 | if let Some(nz_nybble) = prefix.first_different_nybble(&NULL_NODE) { |
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273 | 273 | rev.map_or(Ok((None, steps)), |r| { |
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274 | 274 | has_prefix_or_none(idx, prefix, r) |
|
275 | 275 | .map(|opt| (opt, max(steps, nz_nybble + 1))) |
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276 | 276 | }) |
|
277 | 277 | } else { |
|
278 | 278 | // the prefix is only made of zeros; NULL_REVISION always matches it |
|
279 | 279 | // and any other *valid* result is an ambiguity |
|
280 | 280 | match rev { |
|
281 | 281 | None => Ok((Some(NULL_REVISION), steps + 1)), |
|
282 | 282 | Some(r) => match has_prefix_or_none(idx, prefix, r)? { |
|
283 | 283 | None => Ok((Some(NULL_REVISION), steps + 1)), |
|
284 | 284 | _ => Err(NodeMapError::MultipleResults), |
|
285 | 285 | }, |
|
286 | 286 | } |
|
287 | 287 | } |
|
288 | 288 | } |
|
289 | 289 | |
|
290 | 290 | impl NodeTree { |
|
291 | 291 | /// Initiate a NodeTree from an immutable slice-like of `Block` |
|
292 | 292 | /// |
|
293 | 293 | /// We keep `readonly` and clone its root block if it isn't empty. |
|
294 | 294 | fn new(readonly: Box<dyn Deref<Target = [Block]> + Send>) -> Self { |
|
295 | 295 | let root = readonly.last().cloned().unwrap_or_else(Block::new); |
|
296 | 296 | NodeTree { |
|
297 | 297 | readonly, |
|
298 | 298 | growable: Vec::new(), |
|
299 | 299 | root, |
|
300 | 300 | masked_inner_blocks: 0, |
|
301 | 301 | } |
|
302 | 302 | } |
|
303 | 303 | |
|
304 | 304 | /// Create from an opaque bunch of bytes |
|
305 | 305 | /// |
|
306 | 306 | /// The created [`NodeTreeBytes`] from `bytes`, |
|
307 | 307 | /// of which exactly `amount` bytes are used. |
|
308 | 308 | /// |
|
309 | 309 | /// - `buffer` could be derived from `PyBuffer` and `Mmap` objects. |
|
310 | 310 | /// - `amount` is expressed in bytes, and is not automatically derived from |
|
311 | 311 | /// `bytes`, so that a caller that manages them atomically can perform |
|
312 | 312 | /// temporary disk serializations and still rollback easily if needed. |
|
313 | 313 | /// First use-case for this would be to support Mercurial shell hooks. |
|
314 | 314 | /// |
|
315 | 315 | /// panics if `buffer` is smaller than `amount` |
|
316 | 316 | pub fn load_bytes( |
|
317 | 317 | bytes: Box<dyn Deref<Target = [u8]> + Send>, |
|
318 | 318 | amount: usize, |
|
319 | 319 | ) -> Self { |
|
320 | 320 | NodeTree::new(Box::new(NodeTreeBytes::new(bytes, amount))) |
|
321 | 321 | } |
|
322 | 322 | |
|
323 | 323 | /// Retrieve added [`Block`]s and the original immutable data |
|
324 | 324 | pub fn into_readonly_and_added( |
|
325 | 325 | self, |
|
326 | 326 | ) -> (Box<dyn Deref<Target = [Block]> + Send>, Vec<Block>) { |
|
327 | 327 | let mut vec = self.growable; |
|
328 | 328 | let readonly = self.readonly; |
|
329 | 329 | if readonly.last() != Some(&self.root) { |
|
330 | 330 | vec.push(self.root); |
|
331 | 331 | } |
|
332 | 332 | (readonly, vec) |
|
333 | 333 | } |
|
334 | 334 | |
|
335 | 335 | /// Retrieve added [`Block]s as bytes, ready to be written to persistent |
|
336 | 336 | /// storage |
|
337 | 337 | pub fn into_readonly_and_added_bytes( |
|
338 | 338 | self, |
|
339 | 339 | ) -> (Box<dyn Deref<Target = [Block]> + Send>, Vec<u8>) { |
|
340 | 340 | let (readonly, vec) = self.into_readonly_and_added(); |
|
341 | 341 | // Prevent running `v`'s destructor so we are in complete control |
|
342 | 342 | // of the allocation. |
|
343 | 343 | let vec = mem::ManuallyDrop::new(vec); |
|
344 | 344 | |
|
345 | 345 | // Transmute the `Vec<Block>` to a `Vec<u8>`. Blocks are contiguous |
|
346 | 346 | // bytes, so this is perfectly safe. |
|
347 | 347 | let bytes = unsafe { |
|
348 | 348 | // Check for compatible allocation layout. |
|
349 | 349 | // (Optimized away by constant-folding + dead code elimination.) |
|
350 | 350 | assert_eq!(size_of::<Block>(), 64); |
|
351 | 351 | assert_eq!(align_of::<Block>(), 1); |
|
352 | 352 | |
|
353 | 353 | // /!\ Any use of `vec` after this is use-after-free. |
|
354 | 354 | // TODO: use `into_raw_parts` once stabilized |
|
355 | 355 | Vec::from_raw_parts( |
|
356 | 356 | vec.as_ptr() as *mut u8, |
|
357 | 357 | vec.len() * size_of::<Block>(), |
|
358 | 358 | vec.capacity() * size_of::<Block>(), |
|
359 | 359 | ) |
|
360 | 360 | }; |
|
361 | 361 | (readonly, bytes) |
|
362 | 362 | } |
|
363 | 363 | |
|
364 | 364 | /// Total number of blocks |
|
365 | 365 | fn len(&self) -> usize { |
|
366 | 366 | self.readonly.len() + self.growable.len() + 1 |
|
367 | 367 | } |
|
368 | 368 | |
|
369 | 369 | /// Implemented for completeness |
|
370 | 370 | /// |
|
371 | 371 | /// A `NodeTree` always has at least the mutable root block. |
|
372 | 372 | #[allow(dead_code)] |
|
373 | 373 | fn is_empty(&self) -> bool { |
|
374 | 374 | false |
|
375 | 375 | } |
|
376 | 376 | |
|
377 | 377 | /// Main working method for `NodeTree` searches |
|
378 | 378 | /// |
|
379 | 379 | /// The first returned value is the result of analysing `NodeTree` data |
|
380 | 380 | /// *alone*: whereas `None` guarantees that the given prefix is absent |
|
381 | 381 | /// from the [`NodeTree`] data (but still could match [`NULL_NODE`]), with |
|
382 | 382 | /// `Some(rev)`, it is to be understood that `rev` is the unique |
|
383 | 383 | /// [`Revision`] that could match the prefix. Actually, all that can |
|
384 | 384 | /// be inferred from |
|
385 | 385 | /// the `NodeTree` data is that `rev` is the revision with the longest |
|
386 | 386 | /// common node prefix with the given prefix. |
|
387 | 387 | /// |
|
388 | 388 | /// The second returned value is the size of the smallest subprefix |
|
389 | 389 | /// of `prefix` that would give the same result, i.e. not the |
|
390 | 390 | /// [MultipleResults](NodeMapError) error variant (again, using only the |
|
391 | 391 | /// data of the [`NodeTree`]). |
|
392 | 392 | fn lookup( |
|
393 | 393 | &self, |
|
394 | 394 | prefix: NodePrefix, |
|
395 | 395 | ) -> Result<(Option<Revision>, usize), NodeMapError> { |
|
396 | 396 | for (i, visit_item) in self.visit(prefix).enumerate() { |
|
397 | 397 | if let Some(opt) = visit_item.final_revision() { |
|
398 | 398 | return Ok((opt, i + 1)); |
|
399 | 399 | } |
|
400 | 400 | } |
|
401 | 401 | Err(NodeMapError::MultipleResults) |
|
402 | 402 | } |
|
403 | 403 | |
|
404 | 404 | fn visit(&self, prefix: NodePrefix) -> NodeTreeVisitor { |
|
405 | 405 | NodeTreeVisitor { |
|
406 | 406 | nt: self, |
|
407 | 407 | prefix, |
|
408 | 408 | visit: self.len() - 1, |
|
409 | 409 | nybble_idx: 0, |
|
410 | 410 | done: false, |
|
411 | 411 | } |
|
412 | 412 | } |
|
413 | 413 | /// Return a mutable reference for `Block` at index `idx`. |
|
414 | 414 | /// |
|
415 | 415 | /// If `idx` lies in the immutable area, then the reference is to |
|
416 | 416 | /// a newly appended copy. |
|
417 | 417 | /// |
|
418 | 418 | /// Returns (new_idx, glen, mut_ref) where |
|
419 | 419 | /// |
|
420 | 420 | /// - `new_idx` is the index of the mutable `Block` |
|
421 | 421 | /// - `mut_ref` is a mutable reference to the mutable Block. |
|
422 | 422 | /// - `glen` is the new length of `self.growable` |
|
423 | 423 | /// |
|
424 | 424 | /// Note: the caller wouldn't be allowed to query `self.growable.len()` |
|
425 | 425 | /// itself because of the mutable borrow taken with the returned `Block` |
|
426 | 426 | fn mutable_block(&mut self, idx: usize) -> (usize, &mut Block, usize) { |
|
427 | 427 | let ro_blocks = &self.readonly; |
|
428 | 428 | let ro_len = ro_blocks.len(); |
|
429 | 429 | let glen = self.growable.len(); |
|
430 | 430 | if idx < ro_len { |
|
431 | 431 | self.masked_inner_blocks += 1; |
|
432 | 432 | self.growable.push(ro_blocks[idx]); |
|
433 | 433 | (glen + ro_len, &mut self.growable[glen], glen + 1) |
|
434 | 434 | } else if glen + ro_len == idx { |
|
435 | 435 | (idx, &mut self.root, glen) |
|
436 | 436 | } else { |
|
437 | 437 | (idx, &mut self.growable[idx - ro_len], glen) |
|
438 | 438 | } |
|
439 | 439 | } |
|
440 | 440 | |
|
441 | 441 | /// Main insertion method |
|
442 | 442 | /// |
|
443 | 443 | /// This will dive in the node tree to find the deepest `Block` for |
|
444 | 444 | /// `node`, split it as much as needed and record `node` in there. |
|
445 | 445 | /// The method then backtracks, updating references in all the visited |
|
446 | 446 | /// blocks from the root. |
|
447 | 447 | /// |
|
448 | 448 | /// All the mutated `Block` are copied first to the growable part if |
|
449 | 449 | /// needed. That happens for those in the immutable part except the root. |
|
450 | 450 | pub fn insert<I: RevlogIndex>( |
|
451 | 451 | &mut self, |
|
452 | 452 | index: &I, |
|
453 | 453 | node: &Node, |
|
454 | 454 | rev: Revision, |
|
455 | 455 | ) -> Result<(), NodeMapError> { |
|
456 | 456 | let ro_len = &self.readonly.len(); |
|
457 | 457 | |
|
458 | 458 | let mut visit_steps: Vec<_> = self.visit(node.into()).collect(); |
|
459 | 459 | let read_nybbles = visit_steps.len(); |
|
460 | 460 | // visit_steps cannot be empty, since we always visit the root block |
|
461 | 461 | let deepest = visit_steps.pop().unwrap(); |
|
462 | 462 | |
|
463 | 463 | let (mut block_idx, mut block, mut glen) = |
|
464 | 464 | self.mutable_block(deepest.block_idx); |
|
465 | 465 | |
|
466 | 466 | if let Element::Rev(old_rev) = deepest.element { |
|
467 | 467 | let old_node = index |
|
468 | 468 | .node(old_rev) |
|
469 | 469 | .ok_or(NodeMapError::RevisionNotInIndex(old_rev))?; |
|
470 | 470 | if old_node == node { |
|
471 | 471 | return Ok(()); // avoid creating lots of useless blocks |
|
472 | 472 | } |
|
473 | 473 | |
|
474 | 474 | // Looping over the tail of nybbles in both nodes, creating |
|
475 | 475 | // new blocks until we find the difference |
|
476 | 476 | let mut new_block_idx = ro_len + glen; |
|
477 | 477 | let mut nybble = deepest.nybble; |
|
478 | 478 | for nybble_pos in read_nybbles..node.nybbles_len() { |
|
479 | 479 | block.set(nybble, Element::Block(new_block_idx)); |
|
480 | 480 | |
|
481 | 481 | let new_nybble = node.get_nybble(nybble_pos); |
|
482 | 482 | let old_nybble = old_node.get_nybble(nybble_pos); |
|
483 | 483 | |
|
484 | 484 | if old_nybble == new_nybble { |
|
485 | 485 | self.growable.push(Block::new()); |
|
486 | 486 | block = &mut self.growable[glen]; |
|
487 | 487 | glen += 1; |
|
488 | 488 | new_block_idx += 1; |
|
489 | 489 | nybble = new_nybble; |
|
490 | 490 | } else { |
|
491 | 491 | let mut new_block = Block::new(); |
|
492 | 492 | new_block.set(old_nybble, Element::Rev(old_rev)); |
|
493 | 493 | new_block.set(new_nybble, Element::Rev(rev)); |
|
494 | 494 | self.growable.push(new_block); |
|
495 | 495 | break; |
|
496 | 496 | } |
|
497 | 497 | } |
|
498 | 498 | } else { |
|
499 | 499 | // Free slot in the deepest block: no splitting has to be done |
|
500 | 500 | block.set(deepest.nybble, Element::Rev(rev)); |
|
501 | 501 | } |
|
502 | 502 | |
|
503 | 503 | // Backtrack over visit steps to update references |
|
504 | 504 | while let Some(visited) = visit_steps.pop() { |
|
505 | 505 | let to_write = Element::Block(block_idx); |
|
506 | 506 | if visit_steps.is_empty() { |
|
507 | 507 | self.root.set(visited.nybble, to_write); |
|
508 | 508 | break; |
|
509 | 509 | } |
|
510 | 510 | let (new_idx, block, _) = self.mutable_block(visited.block_idx); |
|
511 | 511 | if block.get(visited.nybble) == to_write { |
|
512 | 512 | break; |
|
513 | 513 | } |
|
514 | 514 | block.set(visited.nybble, to_write); |
|
515 | 515 | block_idx = new_idx; |
|
516 | 516 | } |
|
517 | 517 | Ok(()) |
|
518 | 518 | } |
|
519 | 519 | |
|
520 | 520 | /// Make the whole `NodeTree` logically empty, without touching the |
|
521 | 521 | /// immutable part. |
|
522 | 522 | pub fn invalidate_all(&mut self) { |
|
523 | 523 | self.root = Block::new(); |
|
524 | 524 | self.growable = Vec::new(); |
|
525 | 525 | self.masked_inner_blocks = self.readonly.len(); |
|
526 | 526 | } |
|
527 | 527 | |
|
528 | 528 | /// Return the number of blocks in the readonly part that are currently |
|
529 | 529 | /// masked in the mutable part. |
|
530 | 530 | /// |
|
531 | 531 | /// The `NodeTree` structure has no efficient way to know how many blocks |
|
532 | 532 | /// are already unreachable in the readonly part. |
|
533 | 533 | /// |
|
534 | 534 | /// After a call to `invalidate_all()`, the returned number can be actually |
|
535 | 535 | /// bigger than the whole readonly part, a conventional way to mean that |
|
536 | 536 | /// all the readonly blocks have been masked. This is what is really |
|
537 | 537 | /// useful to the caller and does not require to know how many were |
|
538 | 538 | /// actually unreachable to begin with. |
|
539 | 539 | pub fn masked_readonly_blocks(&self) -> usize { |
|
540 | 540 | if let Some(readonly_root) = self.readonly.last() { |
|
541 | 541 | if readonly_root == &self.root { |
|
542 | 542 | return 0; |
|
543 | 543 | } |
|
544 | 544 | } else { |
|
545 | 545 | return 0; |
|
546 | 546 | } |
|
547 | 547 | self.masked_inner_blocks + 1 |
|
548 | 548 | } |
|
549 | 549 | } |
|
550 | 550 | |
|
551 | 551 | pub struct NodeTreeBytes { |
|
552 | 552 | buffer: Box<dyn Deref<Target = [u8]> + Send>, |
|
553 | 553 | len_in_blocks: usize, |
|
554 | 554 | } |
|
555 | 555 | |
|
556 | 556 | impl NodeTreeBytes { |
|
557 | 557 | fn new( |
|
558 | 558 | buffer: Box<dyn Deref<Target = [u8]> + Send>, |
|
559 | 559 | amount: usize, |
|
560 | 560 | ) -> Self { |
|
561 | 561 | assert!(buffer.len() >= amount); |
|
562 | 562 | let len_in_blocks = amount / size_of::<Block>(); |
|
563 | 563 | NodeTreeBytes { |
|
564 | 564 | buffer, |
|
565 | 565 | len_in_blocks, |
|
566 | 566 | } |
|
567 | 567 | } |
|
568 | 568 | } |
|
569 | 569 | |
|
570 | 570 | impl Deref for NodeTreeBytes { |
|
571 | 571 | type Target = [Block]; |
|
572 | 572 | |
|
573 | 573 | fn deref(&self) -> &[Block] { |
|
574 | 574 | Block::slice_from_bytes(&self.buffer, self.len_in_blocks) |
|
575 | 575 | // `NodeTreeBytes::new` already asserted that `self.buffer` is |
|
576 | 576 | // large enough. |
|
577 | 577 | .unwrap() |
|
578 | 578 | .0 |
|
579 | 579 | } |
|
580 | 580 | } |
|
581 | 581 | |
|
582 | 582 | struct NodeTreeVisitor<'n> { |
|
583 | 583 | nt: &'n NodeTree, |
|
584 | 584 | prefix: NodePrefix, |
|
585 | 585 | visit: usize, |
|
586 | 586 | nybble_idx: usize, |
|
587 | 587 | done: bool, |
|
588 | 588 | } |
|
589 | 589 | |
|
590 | 590 | #[derive(Debug, PartialEq, Clone)] |
|
591 | 591 | struct NodeTreeVisitItem { |
|
592 | 592 | block_idx: usize, |
|
593 | 593 | nybble: u8, |
|
594 | 594 | element: Element, |
|
595 | 595 | } |
|
596 | 596 | |
|
597 | 597 | impl<'n> Iterator for NodeTreeVisitor<'n> { |
|
598 | 598 | type Item = NodeTreeVisitItem; |
|
599 | 599 | |
|
600 | 600 | fn next(&mut self) -> Option<Self::Item> { |
|
601 | 601 | if self.done || self.nybble_idx >= self.prefix.nybbles_len() { |
|
602 | 602 | return None; |
|
603 | 603 | } |
|
604 | 604 | |
|
605 | 605 | let nybble = self.prefix.get_nybble(self.nybble_idx); |
|
606 | 606 | self.nybble_idx += 1; |
|
607 | 607 | |
|
608 | 608 | let visit = self.visit; |
|
609 | 609 | let element = self.nt[visit].get(nybble); |
|
610 | 610 | if let Element::Block(idx) = element { |
|
611 | 611 | self.visit = idx; |
|
612 | 612 | } else { |
|
613 | 613 | self.done = true; |
|
614 | 614 | } |
|
615 | 615 | |
|
616 | 616 | Some(NodeTreeVisitItem { |
|
617 | 617 | block_idx: visit, |
|
618 | 618 | nybble, |
|
619 | 619 | element, |
|
620 | 620 | }) |
|
621 | 621 | } |
|
622 | 622 | } |
|
623 | 623 | |
|
624 | 624 | impl NodeTreeVisitItem { |
|
625 | 625 | // Return `Some(opt)` if this item is final, with `opt` being the |
|
626 | 626 | // `Revision` that it may represent. |
|
627 | 627 | // |
|
628 | 628 | // If the item is not terminal, return `None` |
|
629 | 629 | fn final_revision(&self) -> Option<Option<Revision>> { |
|
630 | 630 | match self.element { |
|
631 | 631 | Element::Block(_) => None, |
|
632 | 632 | Element::Rev(r) => Some(Some(r)), |
|
633 | 633 | Element::None => Some(None), |
|
634 | 634 | } |
|
635 | 635 | } |
|
636 | 636 | } |
|
637 | 637 | |
|
638 | 638 | impl From<Vec<Block>> for NodeTree { |
|
639 | 639 | fn from(vec: Vec<Block>) -> Self { |
|
640 | 640 | Self::new(Box::new(vec)) |
|
641 | 641 | } |
|
642 | 642 | } |
|
643 | 643 | |
|
644 | 644 | impl fmt::Debug for NodeTree { |
|
645 | 645 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
|
646 | 646 | let readonly: &[Block] = &*self.readonly; |
|
647 | 647 | write!( |
|
648 | 648 | f, |
|
649 | 649 | "readonly: {:?}, growable: {:?}, root: {:?}", |
|
650 | 650 | readonly, self.growable, self.root |
|
651 | 651 | ) |
|
652 | 652 | } |
|
653 | 653 | } |
|
654 | 654 | |
|
655 | 655 | impl Default for NodeTree { |
|
656 | 656 | /// Create a fully mutable empty NodeTree |
|
657 | 657 | fn default() -> Self { |
|
658 | 658 | NodeTree::new(Box::new(Vec::new())) |
|
659 | 659 | } |
|
660 | 660 | } |
|
661 | 661 | |
|
662 | 662 | impl NodeMap for NodeTree { |
|
663 | 663 | fn find_bin<'a>( |
|
664 | 664 | &self, |
|
665 | 665 | idx: &impl RevlogIndex, |
|
666 | 666 | prefix: NodePrefix, |
|
667 | 667 | ) -> Result<Option<Revision>, NodeMapError> { |
|
668 | 668 | validate_candidate(idx, prefix, self.lookup(prefix)?) |
|
669 | 669 | .map(|(opt, _shortest)| opt) |
|
670 | 670 | } |
|
671 | 671 | |
|
672 | 672 | fn unique_prefix_len_bin<'a>( |
|
673 | 673 | &self, |
|
674 | 674 | idx: &impl RevlogIndex, |
|
675 | 675 | prefix: NodePrefix, |
|
676 | 676 | ) -> Result<Option<usize>, NodeMapError> { |
|
677 | 677 | validate_candidate(idx, prefix, self.lookup(prefix)?) |
|
678 | 678 | .map(|(opt, shortest)| opt.map(|_rev| shortest)) |
|
679 | 679 | } |
|
680 | 680 | } |
|
681 | 681 | |
|
682 | 682 | #[cfg(test)] |
|
683 | mod tests { | |
|
683 | pub mod tests { | |
|
684 | 684 | use super::NodeMapError::*; |
|
685 | 685 | use super::*; |
|
686 | 686 | use crate::revlog::node::{hex_pad_right, Node}; |
|
687 | 687 | use std::collections::HashMap; |
|
688 | 688 | |
|
689 | 689 | /// Creates a `Block` using a syntax close to the `Debug` output |
|
690 | 690 | macro_rules! block { |
|
691 | 691 | {$($nybble:tt : $variant:ident($val:tt)),*} => ( |
|
692 | 692 | { |
|
693 | 693 | let mut block = Block::new(); |
|
694 | 694 | $(block.set($nybble, Element::$variant($val)));*; |
|
695 | 695 | block |
|
696 | 696 | } |
|
697 | 697 | ) |
|
698 | 698 | } |
|
699 | 699 | |
|
700 | 700 | #[test] |
|
701 | 701 | fn test_block_debug() { |
|
702 | 702 | let mut block = Block::new(); |
|
703 | 703 | block.set(1, Element::Rev(3)); |
|
704 | 704 | block.set(10, Element::Block(0)); |
|
705 | 705 | assert_eq!(format!("{:?}", block), "{1: Rev(3), 10: Block(0)}"); |
|
706 | 706 | } |
|
707 | 707 | |
|
708 | 708 | #[test] |
|
709 | 709 | fn test_block_macro() { |
|
710 | 710 | let block = block! {5: Block(2)}; |
|
711 | 711 | assert_eq!(format!("{:?}", block), "{5: Block(2)}"); |
|
712 | 712 | |
|
713 | 713 | let block = block! {13: Rev(15), 5: Block(2)}; |
|
714 | 714 | assert_eq!(format!("{:?}", block), "{5: Block(2), 13: Rev(15)}"); |
|
715 | 715 | } |
|
716 | 716 | |
|
717 | 717 | #[test] |
|
718 | 718 | fn test_raw_block() { |
|
719 | 719 | let mut raw = [255u8; 64]; |
|
720 | 720 | |
|
721 | 721 | let mut counter = 0; |
|
722 | 722 | for val in [0_i32, 15, -2, -1, -3].iter() { |
|
723 | 723 | for byte in val.to_be_bytes().iter() { |
|
724 | 724 | raw[counter] = *byte; |
|
725 | 725 | counter += 1; |
|
726 | 726 | } |
|
727 | 727 | } |
|
728 | 728 | let (block, _) = Block::from_bytes(&raw).unwrap(); |
|
729 | 729 | assert_eq!(block.get(0), Element::Block(0)); |
|
730 | 730 | assert_eq!(block.get(1), Element::Block(15)); |
|
731 | 731 | assert_eq!(block.get(3), Element::None); |
|
732 | 732 | assert_eq!(block.get(2), Element::Rev(0)); |
|
733 | 733 | assert_eq!(block.get(4), Element::Rev(1)); |
|
734 | 734 | } |
|
735 | 735 | |
|
736 | 736 | type TestIndex = HashMap<Revision, Node>; |
|
737 | 737 | |
|
738 | 738 | impl RevlogIndex for TestIndex { |
|
739 | 739 | fn node(&self, rev: Revision) -> Option<&Node> { |
|
740 | 740 | self.get(&rev) |
|
741 | 741 | } |
|
742 | 742 | |
|
743 | 743 | fn len(&self) -> usize { |
|
744 | 744 | self.len() |
|
745 | 745 | } |
|
746 | 746 | } |
|
747 | 747 | |
|
748 | 748 | /// Pad hexadecimal Node prefix with zeros on the right |
|
749 | 749 | /// |
|
750 | 750 | /// This avoids having to repeatedly write very long hexadecimal |
|
751 | 751 | /// strings for test data, and brings actual hash size independency. |
|
752 | 752 | #[cfg(test)] |
|
753 | 753 | fn pad_node(hex: &str) -> Node { |
|
754 | 754 | Node::from_hex(&hex_pad_right(hex)).unwrap() |
|
755 | 755 | } |
|
756 | 756 | |
|
757 | 757 | /// Pad hexadecimal Node prefix with zeros on the right, then insert |
|
758 | 758 | fn pad_insert(idx: &mut TestIndex, rev: Revision, hex: &str) { |
|
759 | 759 | idx.insert(rev, pad_node(hex)); |
|
760 | 760 | } |
|
761 | 761 | |
|
762 | 762 | fn sample_nodetree() -> NodeTree { |
|
763 | 763 | NodeTree::from(vec![ |
|
764 | 764 | block![0: Rev(9)], |
|
765 | 765 | block![0: Rev(0), 1: Rev(9)], |
|
766 | 766 | block![0: Block(1), 1:Rev(1)], |
|
767 | 767 | ]) |
|
768 | 768 | } |
|
769 | 769 | |
|
770 | 770 | fn hex(s: &str) -> NodePrefix { |
|
771 | 771 | NodePrefix::from_hex(s).unwrap() |
|
772 | 772 | } |
|
773 | 773 | |
|
774 | 774 | #[test] |
|
775 | 775 | fn test_nt_debug() { |
|
776 | 776 | let nt = sample_nodetree(); |
|
777 | 777 | assert_eq!( |
|
778 | 778 | format!("{:?}", nt), |
|
779 | 779 | "readonly: \ |
|
780 | 780 | [{0: Rev(9)}, {0: Rev(0), 1: Rev(9)}, {0: Block(1), 1: Rev(1)}], \ |
|
781 | 781 | growable: [], \ |
|
782 | 782 | root: {0: Block(1), 1: Rev(1)}", |
|
783 | 783 | ); |
|
784 | 784 | } |
|
785 | 785 | |
|
786 | 786 | #[test] |
|
787 | 787 | fn test_immutable_find_simplest() -> Result<(), NodeMapError> { |
|
788 | 788 | let mut idx: TestIndex = HashMap::new(); |
|
789 | 789 | pad_insert(&mut idx, 1, "1234deadcafe"); |
|
790 | 790 | |
|
791 | 791 | let nt = NodeTree::from(vec![block! {1: Rev(1)}]); |
|
792 | 792 | assert_eq!(nt.find_bin(&idx, hex("1"))?, Some(1)); |
|
793 | 793 | assert_eq!(nt.find_bin(&idx, hex("12"))?, Some(1)); |
|
794 | 794 | assert_eq!(nt.find_bin(&idx, hex("1234de"))?, Some(1)); |
|
795 | 795 | assert_eq!(nt.find_bin(&idx, hex("1a"))?, None); |
|
796 | 796 | assert_eq!(nt.find_bin(&idx, hex("ab"))?, None); |
|
797 | 797 | |
|
798 | 798 | // and with full binary Nodes |
|
799 | 799 | assert_eq!(nt.find_node(&idx, idx.get(&1).unwrap())?, Some(1)); |
|
800 | 800 | let unknown = Node::from_hex(&hex_pad_right("3d")).unwrap(); |
|
801 | 801 | assert_eq!(nt.find_node(&idx, &unknown)?, None); |
|
802 | 802 | Ok(()) |
|
803 | 803 | } |
|
804 | 804 | |
|
805 | 805 | #[test] |
|
806 | 806 | fn test_immutable_find_one_jump() { |
|
807 | 807 | let mut idx = TestIndex::new(); |
|
808 | 808 | pad_insert(&mut idx, 9, "012"); |
|
809 | 809 | pad_insert(&mut idx, 0, "00a"); |
|
810 | 810 | |
|
811 | 811 | let nt = sample_nodetree(); |
|
812 | 812 | |
|
813 | 813 | assert_eq!(nt.find_bin(&idx, hex("0")), Err(MultipleResults)); |
|
814 | 814 | assert_eq!(nt.find_bin(&idx, hex("01")), Ok(Some(9))); |
|
815 | 815 | assert_eq!(nt.find_bin(&idx, hex("00")), Err(MultipleResults)); |
|
816 | 816 | assert_eq!(nt.find_bin(&idx, hex("00a")), Ok(Some(0))); |
|
817 | 817 | assert_eq!(nt.unique_prefix_len_bin(&idx, hex("00a")), Ok(Some(3))); |
|
818 | 818 | assert_eq!(nt.find_bin(&idx, hex("000")), Ok(Some(NULL_REVISION))); |
|
819 | 819 | } |
|
820 | 820 | |
|
821 | 821 | #[test] |
|
822 | 822 | fn test_mutated_find() -> Result<(), NodeMapError> { |
|
823 | 823 | let mut idx = TestIndex::new(); |
|
824 | 824 | pad_insert(&mut idx, 9, "012"); |
|
825 | 825 | pad_insert(&mut idx, 0, "00a"); |
|
826 | 826 | pad_insert(&mut idx, 2, "cafe"); |
|
827 | 827 | pad_insert(&mut idx, 3, "15"); |
|
828 | 828 | pad_insert(&mut idx, 1, "10"); |
|
829 | 829 | |
|
830 | 830 | let nt = NodeTree { |
|
831 | 831 | readonly: sample_nodetree().readonly, |
|
832 | 832 | growable: vec![block![0: Rev(1), 5: Rev(3)]], |
|
833 | 833 | root: block![0: Block(1), 1:Block(3), 12: Rev(2)], |
|
834 | 834 | masked_inner_blocks: 1, |
|
835 | 835 | }; |
|
836 | 836 | assert_eq!(nt.find_bin(&idx, hex("10"))?, Some(1)); |
|
837 | 837 | assert_eq!(nt.find_bin(&idx, hex("c"))?, Some(2)); |
|
838 | 838 | assert_eq!(nt.unique_prefix_len_bin(&idx, hex("c"))?, Some(1)); |
|
839 | 839 | assert_eq!(nt.find_bin(&idx, hex("00")), Err(MultipleResults)); |
|
840 | 840 | assert_eq!(nt.find_bin(&idx, hex("000"))?, Some(NULL_REVISION)); |
|
841 | 841 | assert_eq!(nt.unique_prefix_len_bin(&idx, hex("000"))?, Some(3)); |
|
842 | 842 | assert_eq!(nt.find_bin(&idx, hex("01"))?, Some(9)); |
|
843 | 843 | assert_eq!(nt.masked_readonly_blocks(), 2); |
|
844 | 844 | Ok(()) |
|
845 | 845 | } |
|
846 | 846 | |
|
847 | struct TestNtIndex { | |
|
848 | index: TestIndex, | |
|
849 | nt: NodeTree, | |
|
847 | pub struct TestNtIndex { | |
|
848 | pub index: TestIndex, | |
|
849 | pub nt: NodeTree, | |
|
850 | 850 | } |
|
851 | 851 | |
|
852 | 852 | impl TestNtIndex { |
|
853 | fn new() -> Self { | |
|
853 | pub fn new() -> Self { | |
|
854 | 854 | TestNtIndex { |
|
855 | 855 | index: HashMap::new(), |
|
856 | 856 | nt: NodeTree::default(), |
|
857 | 857 | } |
|
858 | 858 | } |
|
859 | 859 | |
|
860 | fn insert( | |
|
860 | pub fn insert_node( | |
|
861 | &mut self, | |
|
862 | rev: Revision, | |
|
863 | node: Node, | |
|
864 | ) -> Result<(), NodeMapError> { | |
|
865 | self.index.insert(rev, node); | |
|
866 | self.nt.insert(&self.index, &node, rev)?; | |
|
867 | Ok(()) | |
|
868 | } | |
|
869 | ||
|
870 | pub fn insert( | |
|
861 | 871 | &mut self, |
|
862 | 872 | rev: Revision, |
|
863 | 873 | hex: &str, |
|
864 | 874 | ) -> Result<(), NodeMapError> { |
|
865 |
|
|
|
866 | self.index.insert(rev, node); | |
|
867 | self.nt.insert(&self.index, &node, rev)?; | |
|
868 | Ok(()) | |
|
875 | return self.insert_node(rev, pad_node(hex)); | |
|
869 | 876 | } |
|
870 | 877 | |
|
871 | 878 | fn find_hex( |
|
872 | 879 | &self, |
|
873 | 880 | prefix: &str, |
|
874 | 881 | ) -> Result<Option<Revision>, NodeMapError> { |
|
875 | 882 | self.nt.find_bin(&self.index, hex(prefix)) |
|
876 | 883 | } |
|
877 | 884 | |
|
878 | 885 | fn unique_prefix_len_hex( |
|
879 | 886 | &self, |
|
880 | 887 | prefix: &str, |
|
881 | 888 | ) -> Result<Option<usize>, NodeMapError> { |
|
882 | 889 | self.nt.unique_prefix_len_bin(&self.index, hex(prefix)) |
|
883 | 890 | } |
|
884 | 891 | |
|
885 | 892 | /// Drain `added` and restart a new one |
|
886 | 893 | fn commit(self) -> Self { |
|
887 | 894 | let mut as_vec: Vec<Block> = |
|
888 | 895 | self.nt.readonly.iter().copied().collect(); |
|
889 | 896 | as_vec.extend(self.nt.growable); |
|
890 | 897 | as_vec.push(self.nt.root); |
|
891 | 898 | |
|
892 | 899 | Self { |
|
893 | 900 | index: self.index, |
|
894 | 901 | nt: NodeTree::from(as_vec), |
|
895 | 902 | } |
|
896 | 903 | } |
|
897 | 904 | } |
|
898 | 905 | |
|
899 | 906 | #[test] |
|
900 | 907 | fn test_insert_full_mutable() -> Result<(), NodeMapError> { |
|
901 | 908 | let mut idx = TestNtIndex::new(); |
|
902 | 909 | idx.insert(0, "1234")?; |
|
903 | 910 | assert_eq!(idx.find_hex("1")?, Some(0)); |
|
904 | 911 | assert_eq!(idx.find_hex("12")?, Some(0)); |
|
905 | 912 | |
|
906 | 913 | // let's trigger a simple split |
|
907 | 914 | idx.insert(1, "1a34")?; |
|
908 | 915 | assert_eq!(idx.nt.growable.len(), 1); |
|
909 | 916 | assert_eq!(idx.find_hex("12")?, Some(0)); |
|
910 | 917 | assert_eq!(idx.find_hex("1a")?, Some(1)); |
|
911 | 918 | |
|
912 | 919 | // reinserting is a no_op |
|
913 | 920 | idx.insert(1, "1a34")?; |
|
914 | 921 | assert_eq!(idx.nt.growable.len(), 1); |
|
915 | 922 | assert_eq!(idx.find_hex("12")?, Some(0)); |
|
916 | 923 | assert_eq!(idx.find_hex("1a")?, Some(1)); |
|
917 | 924 | |
|
918 | 925 | idx.insert(2, "1a01")?; |
|
919 | 926 | assert_eq!(idx.nt.growable.len(), 2); |
|
920 | 927 | assert_eq!(idx.find_hex("1a"), Err(NodeMapError::MultipleResults)); |
|
921 | 928 | assert_eq!(idx.find_hex("12")?, Some(0)); |
|
922 | 929 | assert_eq!(idx.find_hex("1a3")?, Some(1)); |
|
923 | 930 | assert_eq!(idx.find_hex("1a0")?, Some(2)); |
|
924 | 931 | assert_eq!(idx.find_hex("1a12")?, None); |
|
925 | 932 | |
|
926 | 933 | // now let's make it split and create more than one additional block |
|
927 | 934 | idx.insert(3, "1a345")?; |
|
928 | 935 | assert_eq!(idx.nt.growable.len(), 4); |
|
929 | 936 | assert_eq!(idx.find_hex("1a340")?, Some(1)); |
|
930 | 937 | assert_eq!(idx.find_hex("1a345")?, Some(3)); |
|
931 | 938 | assert_eq!(idx.find_hex("1a341")?, None); |
|
932 | 939 | |
|
933 | 940 | // there's no readonly block to mask |
|
934 | 941 | assert_eq!(idx.nt.masked_readonly_blocks(), 0); |
|
935 | 942 | Ok(()) |
|
936 | 943 | } |
|
937 | 944 | |
|
938 | 945 | #[test] |
|
939 | 946 | fn test_unique_prefix_len_zero_prefix() { |
|
940 | 947 | let mut idx = TestNtIndex::new(); |
|
941 | 948 | idx.insert(0, "00000abcd").unwrap(); |
|
942 | 949 | |
|
943 | 950 | assert_eq!(idx.find_hex("000"), Err(NodeMapError::MultipleResults)); |
|
944 | 951 | // in the nodetree proper, this will be found at the first nybble |
|
945 | 952 | // yet the correct answer for unique_prefix_len is not 1, nor 1+1, |
|
946 | 953 | // but the first difference with `NULL_NODE` |
|
947 | 954 | assert_eq!(idx.unique_prefix_len_hex("00000a"), Ok(Some(6))); |
|
948 | 955 | assert_eq!(idx.unique_prefix_len_hex("00000ab"), Ok(Some(6))); |
|
949 | 956 | |
|
950 | 957 | // same with odd result |
|
951 | 958 | idx.insert(1, "00123").unwrap(); |
|
952 | 959 | assert_eq!(idx.unique_prefix_len_hex("001"), Ok(Some(3))); |
|
953 | 960 | assert_eq!(idx.unique_prefix_len_hex("0012"), Ok(Some(3))); |
|
954 | 961 | |
|
955 | 962 | // these are unchanged of course |
|
956 | 963 | assert_eq!(idx.unique_prefix_len_hex("00000a"), Ok(Some(6))); |
|
957 | 964 | assert_eq!(idx.unique_prefix_len_hex("00000ab"), Ok(Some(6))); |
|
958 | 965 | } |
|
959 | 966 | |
|
960 | 967 | #[test] |
|
961 | 968 | fn test_insert_extreme_splitting() -> Result<(), NodeMapError> { |
|
962 | 969 | // check that the splitting loop is long enough |
|
963 | 970 | let mut nt_idx = TestNtIndex::new(); |
|
964 | 971 | let nt = &mut nt_idx.nt; |
|
965 | 972 | let idx = &mut nt_idx.index; |
|
966 | 973 | |
|
967 | 974 | let node0_hex = hex_pad_right("444444"); |
|
968 | 975 | let mut node1_hex = hex_pad_right("444444"); |
|
969 | 976 | node1_hex.pop(); |
|
970 | 977 | node1_hex.push('5'); |
|
971 | 978 | let node0 = Node::from_hex(&node0_hex).unwrap(); |
|
972 | 979 | let node1 = Node::from_hex(&node1_hex).unwrap(); |
|
973 | 980 | |
|
974 | 981 | idx.insert(0, node0); |
|
975 | 982 | nt.insert(idx, &node0, 0)?; |
|
976 | 983 | idx.insert(1, node1); |
|
977 | 984 | nt.insert(idx, &node1, 1)?; |
|
978 | 985 | |
|
979 | 986 | assert_eq!(nt.find_bin(idx, (&node0).into())?, Some(0)); |
|
980 | 987 | assert_eq!(nt.find_bin(idx, (&node1).into())?, Some(1)); |
|
981 | 988 | Ok(()) |
|
982 | 989 | } |
|
983 | 990 | |
|
984 | 991 | #[test] |
|
985 | 992 | fn test_insert_partly_immutable() -> Result<(), NodeMapError> { |
|
986 | 993 | let mut idx = TestNtIndex::new(); |
|
987 | 994 | idx.insert(0, "1234")?; |
|
988 | 995 | idx.insert(1, "1235")?; |
|
989 | 996 | idx.insert(2, "131")?; |
|
990 | 997 | idx.insert(3, "cafe")?; |
|
991 | 998 | let mut idx = idx.commit(); |
|
992 | 999 | assert_eq!(idx.find_hex("1234")?, Some(0)); |
|
993 | 1000 | assert_eq!(idx.find_hex("1235")?, Some(1)); |
|
994 | 1001 | assert_eq!(idx.find_hex("131")?, Some(2)); |
|
995 | 1002 | assert_eq!(idx.find_hex("cafe")?, Some(3)); |
|
996 | 1003 | // we did not add anything since init from readonly |
|
997 | 1004 | assert_eq!(idx.nt.masked_readonly_blocks(), 0); |
|
998 | 1005 | |
|
999 | 1006 | idx.insert(4, "123A")?; |
|
1000 | 1007 | assert_eq!(idx.find_hex("1234")?, Some(0)); |
|
1001 | 1008 | assert_eq!(idx.find_hex("1235")?, Some(1)); |
|
1002 | 1009 | assert_eq!(idx.find_hex("131")?, Some(2)); |
|
1003 | 1010 | assert_eq!(idx.find_hex("cafe")?, Some(3)); |
|
1004 | 1011 | assert_eq!(idx.find_hex("123A")?, Some(4)); |
|
1005 | 1012 | // we masked blocks for all prefixes of "123", including the root |
|
1006 | 1013 | assert_eq!(idx.nt.masked_readonly_blocks(), 4); |
|
1007 | 1014 | |
|
1008 | 1015 | eprintln!("{:?}", idx.nt); |
|
1009 | 1016 | idx.insert(5, "c0")?; |
|
1010 | 1017 | assert_eq!(idx.find_hex("cafe")?, Some(3)); |
|
1011 | 1018 | assert_eq!(idx.find_hex("c0")?, Some(5)); |
|
1012 | 1019 | assert_eq!(idx.find_hex("c1")?, None); |
|
1013 | 1020 | assert_eq!(idx.find_hex("1234")?, Some(0)); |
|
1014 | 1021 | // inserting "c0" is just splitting the 'c' slot of the mutable root, |
|
1015 | 1022 | // it doesn't mask anything |
|
1016 | 1023 | assert_eq!(idx.nt.masked_readonly_blocks(), 4); |
|
1017 | 1024 | |
|
1018 | 1025 | Ok(()) |
|
1019 | 1026 | } |
|
1020 | 1027 | |
|
1021 | 1028 | #[test] |
|
1022 | 1029 | fn test_invalidate_all() -> Result<(), NodeMapError> { |
|
1023 | 1030 | let mut idx = TestNtIndex::new(); |
|
1024 | 1031 | idx.insert(0, "1234")?; |
|
1025 | 1032 | idx.insert(1, "1235")?; |
|
1026 | 1033 | idx.insert(2, "131")?; |
|
1027 | 1034 | idx.insert(3, "cafe")?; |
|
1028 | 1035 | let mut idx = idx.commit(); |
|
1029 | 1036 | |
|
1030 | 1037 | idx.nt.invalidate_all(); |
|
1031 | 1038 | |
|
1032 | 1039 | assert_eq!(idx.find_hex("1234")?, None); |
|
1033 | 1040 | assert_eq!(idx.find_hex("1235")?, None); |
|
1034 | 1041 | assert_eq!(idx.find_hex("131")?, None); |
|
1035 | 1042 | assert_eq!(idx.find_hex("cafe")?, None); |
|
1036 | 1043 | // all the readonly blocks have been masked, this is the |
|
1037 | 1044 | // conventional expected response |
|
1038 | 1045 | assert_eq!(idx.nt.masked_readonly_blocks(), idx.nt.readonly.len() + 1); |
|
1039 | 1046 | Ok(()) |
|
1040 | 1047 | } |
|
1041 | 1048 | |
|
1042 | 1049 | #[test] |
|
1043 | 1050 | fn test_into_added_empty() { |
|
1044 | 1051 | assert!(sample_nodetree().into_readonly_and_added().1.is_empty()); |
|
1045 | 1052 | assert!(sample_nodetree() |
|
1046 | 1053 | .into_readonly_and_added_bytes() |
|
1047 | 1054 | .1 |
|
1048 | 1055 | .is_empty()); |
|
1049 | 1056 | } |
|
1050 | 1057 | |
|
1051 | 1058 | #[test] |
|
1052 | 1059 | fn test_into_added_bytes() -> Result<(), NodeMapError> { |
|
1053 | 1060 | let mut idx = TestNtIndex::new(); |
|
1054 | 1061 | idx.insert(0, "1234")?; |
|
1055 | 1062 | let mut idx = idx.commit(); |
|
1056 | 1063 | idx.insert(4, "cafe")?; |
|
1057 | 1064 | let (_, bytes) = idx.nt.into_readonly_and_added_bytes(); |
|
1058 | 1065 | |
|
1059 | 1066 | // only the root block has been changed |
|
1060 | 1067 | assert_eq!(bytes.len(), size_of::<Block>()); |
|
1061 | 1068 | // big endian for -2 |
|
1062 | 1069 | assert_eq!(&bytes[4..2 * 4], [255, 255, 255, 254]); |
|
1063 | 1070 | // big endian for -6 |
|
1064 | 1071 | assert_eq!(&bytes[12 * 4..13 * 4], [255, 255, 255, 250]); |
|
1065 | 1072 | Ok(()) |
|
1066 | 1073 | } |
|
1067 | 1074 | } |
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