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@@ -1,899 +1,909 b'' | |||
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1 | 1 | # transaction.py - simple journaling scheme for mercurial |
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2 | 2 | # |
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3 | 3 | # This transaction scheme is intended to gracefully handle program |
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4 | 4 | # errors and interruptions. More serious failures like system crashes |
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5 | 5 | # can be recovered with an fsck-like tool. As the whole repository is |
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6 | 6 | # effectively log-structured, this should amount to simply truncating |
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7 | 7 | # anything that isn't referenced in the changelog. |
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8 | 8 | # |
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9 | 9 | # Copyright 2005, 2006 Olivia Mackall <olivia@selenic.com> |
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10 | 10 | # |
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11 | 11 | # This software may be used and distributed according to the terms of the |
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12 | 12 | # GNU General Public License version 2 or any later version. |
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13 | 13 | |
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14 | 14 | import errno |
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15 | 15 | import os |
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16 | 16 | |
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17 | 17 | from .i18n import _ |
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18 | 18 | from . import ( |
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19 | 19 | error, |
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20 | 20 | pycompat, |
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21 | 21 | util, |
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22 | 22 | ) |
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23 | 23 | from .utils import stringutil |
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24 | 24 | |
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25 | 25 | version = 2 |
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26 | 26 | |
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27 | 27 | GEN_GROUP_ALL = b'all' |
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28 | 28 | GEN_GROUP_PRE_FINALIZE = b'prefinalize' |
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29 | 29 | GEN_GROUP_POST_FINALIZE = b'postfinalize' |
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30 | 30 | |
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31 | 31 | |
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32 | 32 | def active(func): |
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33 | 33 | def _active(self, *args, **kwds): |
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34 | 34 | if self._count == 0: |
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35 | 35 | raise error.ProgrammingError( |
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36 | 36 | b'cannot use transaction when it is already committed/aborted' |
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37 | 37 | ) |
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38 | 38 | return func(self, *args, **kwds) |
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39 | 39 | |
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40 | 40 | return _active |
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41 | 41 | |
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42 | 42 | |
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43 | 43 | UNDO_BACKUP = b'%s.backupfiles' |
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44 | 44 | |
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45 | 45 | UNDO_FILES_MAY_NEED_CLEANUP = [ |
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46 | 46 | # legacy entries that might exists on disk from previous version: |
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47 | 47 | (b'store', b'%s.narrowspec'), |
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48 | 48 | (b'plain', b'%s.narrowspec.dirstate'), |
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49 | 49 | (b'plain', b'%s.branch'), |
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50 | 50 | (b'plain', b'%s.bookmarks'), |
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51 | 51 | (b'store', b'%s.phaseroots'), |
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52 | 52 | (b'plain', b'%s.dirstate'), |
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53 | 53 | # files actually in uses today: |
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54 | 54 | (b'plain', b'%s.desc'), |
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55 | 55 | # Always delete undo last to make sure we detect that a clean up is needed if |
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56 | 56 | # the process is interrupted. |
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57 | 57 | (b'store', b'%s'), |
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58 | 58 | ] |
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59 | 59 | |
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60 | 60 | |
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61 | 61 | def cleanup_undo_files(report, vfsmap, undo_prefix=b'undo'): |
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62 | 62 | """remove "undo" files used by the rollback logic |
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63 | 63 | |
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64 | 64 | This is useful to prevent rollback running in situation were it does not |
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65 | 65 | make sense. For example after a strip. |
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66 | 66 | """ |
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67 | 67 | backup_listing = UNDO_BACKUP % undo_prefix |
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68 | 68 | |
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69 | 69 | backup_entries = [] |
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70 | 70 | undo_files = [] |
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71 | 71 | svfs = vfsmap[b'store'] |
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72 | 72 | try: |
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73 | 73 | with svfs(backup_listing) as f: |
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74 | 74 | backup_entries = read_backup_files(report, f) |
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75 | 75 | except OSError as e: |
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76 | 76 | if e.errno != errno.ENOENT: |
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77 | 77 | msg = _(b'could not read %s: %s\n') |
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78 | 78 | msg %= (svfs.join(backup_listing), stringutil.forcebytestr(e)) |
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79 | 79 | report(msg) |
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80 | 80 | |
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81 | 81 | for location, f, backup_path, c in backup_entries: |
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82 | 82 | if location in vfsmap and backup_path: |
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83 | 83 | undo_files.append((vfsmap[location], backup_path)) |
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84 | 84 | |
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85 | 85 | undo_files.append((svfs, backup_listing)) |
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86 | 86 | for location, undo_path in UNDO_FILES_MAY_NEED_CLEANUP: |
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87 | 87 | undo_files.append((vfsmap[location], undo_path % undo_prefix)) |
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88 | 88 | for undovfs, undofile in undo_files: |
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89 | 89 | try: |
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90 | 90 | undovfs.unlink(undofile) |
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91 | 91 | except OSError as e: |
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92 | 92 | if e.errno != errno.ENOENT: |
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93 | 93 | msg = _(b'error removing %s: %s\n') |
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94 | 94 | msg %= (undovfs.join(undofile), stringutil.forcebytestr(e)) |
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95 | 95 | report(msg) |
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96 | 96 | |
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97 | 97 | |
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98 | 98 | def _playback( |
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99 | 99 | journal, |
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100 | 100 | report, |
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101 | 101 | opener, |
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102 | 102 | vfsmap, |
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103 | 103 | entries, |
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104 | 104 | backupentries, |
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105 | 105 | unlink=True, |
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106 | 106 | checkambigfiles=None, |
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107 | 107 | ): |
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108 | 108 | for f, o in sorted(dict(entries).items()): |
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109 | 109 | if o or not unlink: |
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110 | 110 | checkambig = checkambigfiles and (f, b'') in checkambigfiles |
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111 | 111 | try: |
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112 | 112 | fp = opener(f, b'a', checkambig=checkambig) |
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113 | 113 | if fp.tell() < o: |
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114 | 114 | raise error.Abort( |
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115 | 115 | _( |
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116 | 116 | b"attempted to truncate %s to %d bytes, but it was " |
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117 | 117 | b"already %d bytes\n" |
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118 | 118 | ) |
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119 | 119 | % (f, o, fp.tell()) |
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120 | 120 | ) |
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121 | 121 | fp.truncate(o) |
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122 | 122 | fp.close() |
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123 | 123 | except IOError: |
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124 | 124 | report(_(b"failed to truncate %s\n") % f) |
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125 | 125 | raise |
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126 | 126 | else: |
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127 | 127 | try: |
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128 | 128 | opener.unlink(f) |
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129 | 129 | except FileNotFoundError: |
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130 | 130 | pass |
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131 | 131 | |
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132 | 132 | backupfiles = [] |
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133 | 133 | for l, f, b, c in backupentries: |
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134 | 134 | if l not in vfsmap and c: |
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135 | 135 | report(b"couldn't handle %s: unknown cache location %s\n" % (b, l)) |
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136 | 136 | vfs = vfsmap[l] |
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137 | 137 | try: |
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138 | 138 | if f and b: |
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139 | 139 | filepath = vfs.join(f) |
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140 | 140 | backuppath = vfs.join(b) |
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141 | 141 | checkambig = checkambigfiles and (f, l) in checkambigfiles |
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142 | 142 | try: |
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143 | 143 | util.copyfile(backuppath, filepath, checkambig=checkambig) |
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144 | 144 | backupfiles.append((vfs, b)) |
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145 | 145 | except IOError as exc: |
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146 | 146 | e_msg = stringutil.forcebytestr(exc) |
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147 | 147 | report(_(b"failed to recover %s (%s)\n") % (f, e_msg)) |
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148 | 148 | else: |
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149 | 149 | target = f or b |
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150 | 150 | try: |
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151 | 151 | vfs.unlink(target) |
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152 | 152 | except FileNotFoundError: |
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153 | # This is fine because | |
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154 | # | |
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155 | # either we are trying to delete the main file, and it is | |
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156 | # already deleted. | |
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157 | # | |
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158 | # or we are trying to delete a temporary file and it is | |
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159 | # already deleted. | |
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160 | # | |
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161 | # in both case, our target result (delete the file) is | |
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162 | # already achieved. | |
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153 | 163 | pass |
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154 | 164 | except (IOError, OSError, error.Abort): |
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155 | 165 | if not c: |
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156 | 166 | raise |
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157 | 167 | |
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158 | 168 | backuppath = b"%s.backupfiles" % journal |
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159 | 169 | if opener.exists(backuppath): |
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160 | 170 | opener.unlink(backuppath) |
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161 | 171 | opener.unlink(journal) |
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162 | 172 | try: |
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163 | 173 | for vfs, f in backupfiles: |
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164 | 174 | if vfs.exists(f): |
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165 | 175 | vfs.unlink(f) |
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166 | 176 | except (IOError, OSError, error.Abort): |
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167 | 177 | # only pure backup file remains, it is sage to ignore any error |
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168 | 178 | pass |
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169 | 179 | |
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170 | 180 | |
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171 | 181 | class transaction(util.transactional): |
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172 | 182 | def __init__( |
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173 | 183 | self, |
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174 | 184 | report, |
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175 | 185 | opener, |
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176 | 186 | vfsmap, |
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177 | 187 | journalname, |
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178 | 188 | undoname=None, |
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179 | 189 | after=None, |
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180 | 190 | createmode=None, |
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181 | 191 | validator=None, |
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182 | 192 | releasefn=None, |
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183 | 193 | checkambigfiles=None, |
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184 | 194 | name='<unnamed>', |
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185 | 195 | ): |
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186 | 196 | """Begin a new transaction |
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187 | 197 | |
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188 | 198 | Begins a new transaction that allows rolling back writes in the event of |
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189 | 199 | an exception. |
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190 | 200 | |
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191 | 201 | * `after`: called after the transaction has been committed |
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192 | 202 | * `createmode`: the mode of the journal file that will be created |
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193 | 203 | * `releasefn`: called after releasing (with transaction and result) |
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194 | 204 | |
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195 | 205 | `checkambigfiles` is a set of (path, vfs-location) tuples, |
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196 | 206 | which determine whether file stat ambiguity should be avoided |
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197 | 207 | for corresponded files. |
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198 | 208 | """ |
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199 | 209 | self._count = 1 |
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200 | 210 | self._usages = 1 |
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201 | 211 | self._report = report |
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202 | 212 | # a vfs to the store content |
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203 | 213 | self._opener = opener |
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204 | 214 | # a map to access file in various {location -> vfs} |
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205 | 215 | vfsmap = vfsmap.copy() |
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206 | 216 | vfsmap[b''] = opener # set default value |
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207 | 217 | self._vfsmap = vfsmap |
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208 | 218 | self._after = after |
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209 | 219 | self._offsetmap = {} |
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210 | 220 | self._newfiles = set() |
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211 | 221 | self._journal = journalname |
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212 | 222 | self._journal_files = [] |
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213 | 223 | self._undoname = undoname |
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214 | 224 | self._queue = [] |
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215 | 225 | # A callback to do something just after releasing transaction. |
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216 | 226 | if releasefn is None: |
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217 | 227 | releasefn = lambda tr, success: None |
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218 | 228 | self._releasefn = releasefn |
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219 | 229 | |
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220 | 230 | self._checkambigfiles = set() |
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221 | 231 | if checkambigfiles: |
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222 | 232 | self._checkambigfiles.update(checkambigfiles) |
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223 | 233 | |
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224 | 234 | self._names = [name] |
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225 | 235 | |
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226 | 236 | # A dict dedicated to precisely tracking the changes introduced in the |
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227 | 237 | # transaction. |
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228 | 238 | self.changes = {} |
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229 | 239 | |
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230 | 240 | # a dict of arguments to be passed to hooks |
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231 | 241 | self.hookargs = {} |
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232 | 242 | self._file = opener.open(self._journal, b"w+") |
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233 | 243 | |
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234 | 244 | # a list of ('location', 'path', 'backuppath', cache) entries. |
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235 | 245 | # - if 'backuppath' is empty, no file existed at backup time |
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236 | 246 | # - if 'path' is empty, this is a temporary transaction file |
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237 | 247 | # - if 'location' is not empty, the path is outside main opener reach. |
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238 | 248 | # use 'location' value as a key in a vfsmap to find the right 'vfs' |
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239 | 249 | # (cache is currently unused) |
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240 | 250 | self._backupentries = [] |
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241 | 251 | self._backupmap = {} |
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242 | 252 | self._backupjournal = b"%s.backupfiles" % self._journal |
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243 | 253 | self._backupsfile = opener.open(self._backupjournal, b'w') |
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244 | 254 | self._backupsfile.write(b'%d\n' % version) |
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245 | 255 | |
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246 | 256 | if createmode is not None: |
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247 | 257 | opener.chmod(self._journal, createmode & 0o666) |
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248 | 258 | opener.chmod(self._backupjournal, createmode & 0o666) |
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249 | 259 | |
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250 | 260 | # hold file generations to be performed on commit |
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251 | 261 | self._filegenerators = {} |
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252 | 262 | # hold callback to write pending data for hooks |
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253 | 263 | self._pendingcallback = {} |
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254 | 264 | # True is any pending data have been written ever |
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255 | 265 | self._anypending = False |
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256 | 266 | # holds callback to call when writing the transaction |
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257 | 267 | self._finalizecallback = {} |
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258 | 268 | # holds callback to call when validating the transaction |
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259 | 269 | # should raise exception if anything is wrong |
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260 | 270 | self._validatecallback = {} |
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261 | 271 | if validator is not None: |
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262 | 272 | self._validatecallback[b'001-userhooks'] = validator |
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263 | 273 | # hold callback for post transaction close |
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264 | 274 | self._postclosecallback = {} |
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265 | 275 | # holds callbacks to call during abort |
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266 | 276 | self._abortcallback = {} |
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267 | 277 | |
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268 | 278 | def __repr__(self): |
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269 | 279 | name = '/'.join(self._names) |
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270 | 280 | return '<transaction name=%s, count=%d, usages=%d>' % ( |
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271 | 281 | name, |
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272 | 282 | self._count, |
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273 | 283 | self._usages, |
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274 | 284 | ) |
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275 | 285 | |
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276 | 286 | def __del__(self): |
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277 | 287 | if self._journal: |
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278 | 288 | self._abort() |
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279 | 289 | |
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280 | 290 | @property |
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281 | 291 | def finalized(self): |
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282 | 292 | return self._finalizecallback is None |
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283 | 293 | |
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284 | 294 | @active |
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285 | 295 | def startgroup(self): |
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286 | 296 | """delay registration of file entry |
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287 | 297 | |
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288 | 298 | This is used by strip to delay vision of strip offset. The transaction |
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289 | 299 | sees either none or all of the strip actions to be done.""" |
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290 | 300 | self._queue.append([]) |
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291 | 301 | |
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292 | 302 | @active |
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293 | 303 | def endgroup(self): |
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294 | 304 | """apply delayed registration of file entry. |
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295 | 305 | |
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296 | 306 | This is used by strip to delay vision of strip offset. The transaction |
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297 | 307 | sees either none or all of the strip actions to be done.""" |
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298 | 308 | q = self._queue.pop() |
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299 | 309 | for f, o in q: |
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300 | 310 | self._addentry(f, o) |
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301 | 311 | |
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302 | 312 | @active |
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303 | 313 | def add(self, file, offset): |
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304 | 314 | """record the state of an append-only file before update""" |
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305 | 315 | if ( |
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306 | 316 | file in self._newfiles |
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307 | 317 | or file in self._offsetmap |
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308 | 318 | or file in self._backupmap |
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309 | 319 | ): |
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310 | 320 | return |
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311 | 321 | if self._queue: |
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312 | 322 | self._queue[-1].append((file, offset)) |
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313 | 323 | return |
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314 | 324 | |
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315 | 325 | self._addentry(file, offset) |
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316 | 326 | |
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317 | 327 | def _addentry(self, file, offset): |
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318 | 328 | """add a append-only entry to memory and on-disk state""" |
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319 | 329 | if ( |
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320 | 330 | file in self._newfiles |
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321 | 331 | or file in self._offsetmap |
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322 | 332 | or file in self._backupmap |
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323 | 333 | ): |
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324 | 334 | return |
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325 | 335 | if offset: |
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326 | 336 | self._offsetmap[file] = offset |
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327 | 337 | else: |
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328 | 338 | self._newfiles.add(file) |
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329 | 339 | # add enough data to the journal to do the truncate |
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330 | 340 | self._file.write(b"%s\0%d\n" % (file, offset)) |
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331 | 341 | self._file.flush() |
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332 | 342 | |
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333 | 343 | @active |
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334 | 344 | def addbackup(self, file, hardlink=True, location=b''): |
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335 | 345 | """Adds a backup of the file to the transaction |
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336 | 346 | |
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337 | 347 | Calling addbackup() creates a hardlink backup of the specified file |
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338 | 348 | that is used to recover the file in the event of the transaction |
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339 | 349 | aborting. |
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340 | 350 | |
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341 | 351 | * `file`: the file path, relative to .hg/store |
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342 | 352 | * `hardlink`: use a hardlink to quickly create the backup |
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343 | 353 | """ |
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344 | 354 | if self._queue: |
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345 | 355 | msg = b'cannot use transaction.addbackup inside "group"' |
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346 | 356 | raise error.ProgrammingError(msg) |
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347 | 357 | |
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348 | 358 | if ( |
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349 | 359 | file in self._newfiles |
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350 | 360 | or file in self._offsetmap |
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351 | 361 | or file in self._backupmap |
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352 | 362 | ): |
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353 | 363 | return |
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354 | 364 | vfs = self._vfsmap[location] |
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355 | 365 | dirname, filename = vfs.split(file) |
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356 | 366 | backupfilename = b"%s.backup.%s" % (self._journal, filename) |
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357 | 367 | backupfile = vfs.reljoin(dirname, backupfilename) |
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358 | 368 | if vfs.exists(file): |
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359 | 369 | filepath = vfs.join(file) |
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360 | 370 | backuppath = vfs.join(backupfile) |
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361 | 371 | util.copyfile(filepath, backuppath, hardlink=hardlink) |
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362 | 372 | else: |
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363 | 373 | backupfile = b'' |
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364 | 374 | |
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365 | 375 | self._addbackupentry((location, file, backupfile, False)) |
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366 | 376 | |
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367 | 377 | def _addbackupentry(self, entry): |
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368 | 378 | """register a new backup entry and write it to disk""" |
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369 | 379 | self._backupentries.append(entry) |
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370 | 380 | self._backupmap[entry[1]] = len(self._backupentries) - 1 |
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371 | 381 | self._backupsfile.write(b"%s\0%s\0%s\0%d\n" % entry) |
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372 | 382 | self._backupsfile.flush() |
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373 | 383 | |
|
374 | 384 | @active |
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375 | 385 | def registertmp(self, tmpfile, location=b''): |
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376 | 386 | """register a temporary transaction file |
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377 | 387 | |
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378 | 388 | Such files will be deleted when the transaction exits (on both |
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379 | 389 | failure and success). |
|
380 | 390 | """ |
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381 | 391 | self._addbackupentry((location, b'', tmpfile, False)) |
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382 | 392 | |
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383 | 393 | @active |
|
384 | 394 | def addfilegenerator( |
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385 | 395 | self, |
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386 | 396 | genid, |
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387 | 397 | filenames, |
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388 | 398 | genfunc, |
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389 | 399 | order=0, |
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390 | 400 | location=b'', |
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391 | 401 | post_finalize=False, |
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392 | 402 | ): |
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393 | 403 | """add a function to generates some files at transaction commit |
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394 | 404 | |
|
395 | 405 | The `genfunc` argument is a function capable of generating proper |
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396 | 406 | content of each entry in the `filename` tuple. |
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397 | 407 | |
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398 | 408 | At transaction close time, `genfunc` will be called with one file |
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399 | 409 | object argument per entries in `filenames`. |
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400 | 410 | |
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401 | 411 | The transaction itself is responsible for the backup, creation and |
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402 | 412 | final write of such file. |
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403 | 413 | |
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404 | 414 | The `genid` argument is used to ensure the same set of file is only |
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405 | 415 | generated once. Call to `addfilegenerator` for a `genid` already |
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406 | 416 | present will overwrite the old entry. |
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407 | 417 | |
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408 | 418 | The `order` argument may be used to control the order in which multiple |
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409 | 419 | generator will be executed. |
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410 | 420 | |
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411 | 421 | The `location` arguments may be used to indicate the files are located |
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412 | 422 | outside of the the standard directory for transaction. It should match |
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413 | 423 | one of the key of the `transaction.vfsmap` dictionary. |
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414 | 424 | |
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415 | 425 | The `post_finalize` argument can be set to `True` for file generation |
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416 | 426 | that must be run after the transaction has been finalized. |
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417 | 427 | """ |
|
418 | 428 | # For now, we are unable to do proper backup and restore of custom vfs |
|
419 | 429 | # but for bookmarks that are handled outside this mechanism. |
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420 | 430 | entry = (order, filenames, genfunc, location, post_finalize) |
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421 | 431 | self._filegenerators[genid] = entry |
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422 | 432 | |
|
423 | 433 | @active |
|
424 | 434 | def removefilegenerator(self, genid): |
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425 | 435 | """reverse of addfilegenerator, remove a file generator function""" |
|
426 | 436 | if genid in self._filegenerators: |
|
427 | 437 | del self._filegenerators[genid] |
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428 | 438 | |
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429 | 439 | def _generatefiles(self, suffix=b'', group=GEN_GROUP_ALL): |
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430 | 440 | # write files registered for generation |
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431 | 441 | any = False |
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432 | 442 | |
|
433 | 443 | if group == GEN_GROUP_ALL: |
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434 | 444 | skip_post = skip_pre = False |
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435 | 445 | else: |
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436 | 446 | skip_pre = group == GEN_GROUP_POST_FINALIZE |
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437 | 447 | skip_post = group == GEN_GROUP_PRE_FINALIZE |
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438 | 448 | |
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439 | 449 | for id, entry in sorted(self._filegenerators.items()): |
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440 | 450 | any = True |
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441 | 451 | order, filenames, genfunc, location, post_finalize = entry |
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442 | 452 | |
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443 | 453 | # for generation at closing, check if it's before or after finalize |
|
444 | 454 | if skip_post and post_finalize: |
|
445 | 455 | continue |
|
446 | 456 | elif skip_pre and not post_finalize: |
|
447 | 457 | continue |
|
448 | 458 | |
|
449 | 459 | vfs = self._vfsmap[location] |
|
450 | 460 | files = [] |
|
451 | 461 | try: |
|
452 | 462 | for name in filenames: |
|
453 | 463 | name += suffix |
|
454 | 464 | if suffix: |
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455 | 465 | self.registertmp(name, location=location) |
|
456 | 466 | checkambig = False |
|
457 | 467 | else: |
|
458 | 468 | self.addbackup(name, location=location) |
|
459 | 469 | checkambig = (name, location) in self._checkambigfiles |
|
460 | 470 | files.append( |
|
461 | 471 | vfs(name, b'w', atomictemp=True, checkambig=checkambig) |
|
462 | 472 | ) |
|
463 | 473 | genfunc(*files) |
|
464 | 474 | for f in files: |
|
465 | 475 | f.close() |
|
466 | 476 | # skip discard() loop since we're sure no open file remains |
|
467 | 477 | del files[:] |
|
468 | 478 | finally: |
|
469 | 479 | for f in files: |
|
470 | 480 | f.discard() |
|
471 | 481 | return any |
|
472 | 482 | |
|
473 | 483 | @active |
|
474 | 484 | def findoffset(self, file): |
|
475 | 485 | if file in self._newfiles: |
|
476 | 486 | return 0 |
|
477 | 487 | return self._offsetmap.get(file) |
|
478 | 488 | |
|
479 | 489 | @active |
|
480 | 490 | def readjournal(self): |
|
481 | 491 | self._file.seek(0) |
|
482 | 492 | entries = [] |
|
483 | 493 | for l in self._file.readlines(): |
|
484 | 494 | file, troffset = l.split(b'\0') |
|
485 | 495 | entries.append((file, int(troffset))) |
|
486 | 496 | return entries |
|
487 | 497 | |
|
488 | 498 | @active |
|
489 | 499 | def replace(self, file, offset): |
|
490 | 500 | """ |
|
491 | 501 | replace can only replace already committed entries |
|
492 | 502 | that are not pending in the queue |
|
493 | 503 | """ |
|
494 | 504 | if file in self._newfiles: |
|
495 | 505 | if not offset: |
|
496 | 506 | return |
|
497 | 507 | self._newfiles.remove(file) |
|
498 | 508 | self._offsetmap[file] = offset |
|
499 | 509 | elif file in self._offsetmap: |
|
500 | 510 | if not offset: |
|
501 | 511 | del self._offsetmap[file] |
|
502 | 512 | self._newfiles.add(file) |
|
503 | 513 | else: |
|
504 | 514 | self._offsetmap[file] = offset |
|
505 | 515 | else: |
|
506 | 516 | raise KeyError(file) |
|
507 | 517 | self._file.write(b"%s\0%d\n" % (file, offset)) |
|
508 | 518 | self._file.flush() |
|
509 | 519 | |
|
510 | 520 | @active |
|
511 | 521 | def nest(self, name='<unnamed>'): |
|
512 | 522 | self._count += 1 |
|
513 | 523 | self._usages += 1 |
|
514 | 524 | self._names.append(name) |
|
515 | 525 | return self |
|
516 | 526 | |
|
517 | 527 | def release(self): |
|
518 | 528 | if self._count > 0: |
|
519 | 529 | self._usages -= 1 |
|
520 | 530 | if self._names: |
|
521 | 531 | self._names.pop() |
|
522 | 532 | # if the transaction scopes are left without being closed, fail |
|
523 | 533 | if self._count > 0 and self._usages == 0: |
|
524 | 534 | self._abort() |
|
525 | 535 | |
|
526 | 536 | def running(self): |
|
527 | 537 | return self._count > 0 |
|
528 | 538 | |
|
529 | 539 | def addpending(self, category, callback): |
|
530 | 540 | """add a callback to be called when the transaction is pending |
|
531 | 541 | |
|
532 | 542 | The transaction will be given as callback's first argument. |
|
533 | 543 | |
|
534 | 544 | Category is a unique identifier to allow overwriting an old callback |
|
535 | 545 | with a newer callback. |
|
536 | 546 | """ |
|
537 | 547 | self._pendingcallback[category] = callback |
|
538 | 548 | |
|
539 | 549 | @active |
|
540 | 550 | def writepending(self): |
|
541 | 551 | """write pending file to temporary version |
|
542 | 552 | |
|
543 | 553 | This is used to allow hooks to view a transaction before commit""" |
|
544 | 554 | categories = sorted(self._pendingcallback) |
|
545 | 555 | for cat in categories: |
|
546 | 556 | # remove callback since the data will have been flushed |
|
547 | 557 | any = self._pendingcallback.pop(cat)(self) |
|
548 | 558 | self._anypending = self._anypending or any |
|
549 | 559 | self._anypending |= self._generatefiles(suffix=b'.pending') |
|
550 | 560 | return self._anypending |
|
551 | 561 | |
|
552 | 562 | @active |
|
553 | 563 | def hasfinalize(self, category): |
|
554 | 564 | """check is a callback already exist for a category""" |
|
555 | 565 | return category in self._finalizecallback |
|
556 | 566 | |
|
557 | 567 | @active |
|
558 | 568 | def addfinalize(self, category, callback): |
|
559 | 569 | """add a callback to be called when the transaction is closed |
|
560 | 570 | |
|
561 | 571 | The transaction will be given as callback's first argument. |
|
562 | 572 | |
|
563 | 573 | Category is a unique identifier to allow overwriting old callbacks with |
|
564 | 574 | newer callbacks. |
|
565 | 575 | """ |
|
566 | 576 | self._finalizecallback[category] = callback |
|
567 | 577 | |
|
568 | 578 | @active |
|
569 | 579 | def addpostclose(self, category, callback): |
|
570 | 580 | """add or replace a callback to be called after the transaction closed |
|
571 | 581 | |
|
572 | 582 | The transaction will be given as callback's first argument. |
|
573 | 583 | |
|
574 | 584 | Category is a unique identifier to allow overwriting an old callback |
|
575 | 585 | with a newer callback. |
|
576 | 586 | """ |
|
577 | 587 | self._postclosecallback[category] = callback |
|
578 | 588 | |
|
579 | 589 | @active |
|
580 | 590 | def getpostclose(self, category): |
|
581 | 591 | """return a postclose callback added before, or None""" |
|
582 | 592 | return self._postclosecallback.get(category, None) |
|
583 | 593 | |
|
584 | 594 | @active |
|
585 | 595 | def addabort(self, category, callback): |
|
586 | 596 | """add a callback to be called when the transaction is aborted. |
|
587 | 597 | |
|
588 | 598 | The transaction will be given as the first argument to the callback. |
|
589 | 599 | |
|
590 | 600 | Category is a unique identifier to allow overwriting an old callback |
|
591 | 601 | with a newer callback. |
|
592 | 602 | """ |
|
593 | 603 | self._abortcallback[category] = callback |
|
594 | 604 | |
|
595 | 605 | @active |
|
596 | 606 | def addvalidator(self, category, callback): |
|
597 | 607 | """adds a callback to be called when validating the transaction. |
|
598 | 608 | |
|
599 | 609 | The transaction will be given as the first argument to the callback. |
|
600 | 610 | |
|
601 | 611 | callback should raise exception if to abort transaction""" |
|
602 | 612 | self._validatecallback[category] = callback |
|
603 | 613 | |
|
604 | 614 | @active |
|
605 | 615 | def close(self): |
|
606 | 616 | '''commit the transaction''' |
|
607 | 617 | if self._count == 1: |
|
608 | 618 | for category in sorted(self._validatecallback): |
|
609 | 619 | self._validatecallback[category](self) |
|
610 | 620 | self._validatecallback = None # Help prevent cycles. |
|
611 | 621 | self._generatefiles(group=GEN_GROUP_PRE_FINALIZE) |
|
612 | 622 | while self._finalizecallback: |
|
613 | 623 | callbacks = self._finalizecallback |
|
614 | 624 | self._finalizecallback = {} |
|
615 | 625 | categories = sorted(callbacks) |
|
616 | 626 | for cat in categories: |
|
617 | 627 | callbacks[cat](self) |
|
618 | 628 | # Prevent double usage and help clear cycles. |
|
619 | 629 | self._finalizecallback = None |
|
620 | 630 | self._generatefiles(group=GEN_GROUP_POST_FINALIZE) |
|
621 | 631 | |
|
622 | 632 | self._count -= 1 |
|
623 | 633 | if self._count != 0: |
|
624 | 634 | return |
|
625 | 635 | self._file.close() |
|
626 | 636 | self._backupsfile.close() |
|
627 | 637 | # cleanup temporary files |
|
628 | 638 | for l, f, b, c in self._backupentries: |
|
629 | 639 | if l not in self._vfsmap and c: |
|
630 | 640 | self._report( |
|
631 | 641 | b"couldn't remove %s: unknown cache location %s\n" % (b, l) |
|
632 | 642 | ) |
|
633 | 643 | continue |
|
634 | 644 | vfs = self._vfsmap[l] |
|
635 | 645 | if not f and b and vfs.exists(b): |
|
636 | 646 | try: |
|
637 | 647 | vfs.unlink(b) |
|
638 | 648 | except (IOError, OSError, error.Abort) as inst: |
|
639 | 649 | if not c: |
|
640 | 650 | raise |
|
641 | 651 | # Abort may be raise by read only opener |
|
642 | 652 | self._report( |
|
643 | 653 | b"couldn't remove %s: %s\n" % (vfs.join(b), inst) |
|
644 | 654 | ) |
|
645 | 655 | self._offsetmap = {} |
|
646 | 656 | self._newfiles = set() |
|
647 | 657 | self._writeundo() |
|
648 | 658 | if self._after: |
|
649 | 659 | self._after() |
|
650 | 660 | self._after = None # Help prevent cycles. |
|
651 | 661 | if self._opener.isfile(self._backupjournal): |
|
652 | 662 | self._opener.unlink(self._backupjournal) |
|
653 | 663 | if self._opener.isfile(self._journal): |
|
654 | 664 | self._opener.unlink(self._journal) |
|
655 | 665 | for l, _f, b, c in self._backupentries: |
|
656 | 666 | if l not in self._vfsmap and c: |
|
657 | 667 | self._report( |
|
658 | 668 | b"couldn't remove %s: unknown cache location" |
|
659 | 669 | b"%s\n" % (b, l) |
|
660 | 670 | ) |
|
661 | 671 | continue |
|
662 | 672 | vfs = self._vfsmap[l] |
|
663 | 673 | if b and vfs.exists(b): |
|
664 | 674 | try: |
|
665 | 675 | vfs.unlink(b) |
|
666 | 676 | except (IOError, OSError, error.Abort) as inst: |
|
667 | 677 | if not c: |
|
668 | 678 | raise |
|
669 | 679 | # Abort may be raise by read only opener |
|
670 | 680 | self._report( |
|
671 | 681 | b"couldn't remove %s: %s\n" % (vfs.join(b), inst) |
|
672 | 682 | ) |
|
673 | 683 | self._backupentries = [] |
|
674 | 684 | self._journal = None |
|
675 | 685 | |
|
676 | 686 | self._releasefn(self, True) # notify success of closing transaction |
|
677 | 687 | self._releasefn = None # Help prevent cycles. |
|
678 | 688 | |
|
679 | 689 | # run post close action |
|
680 | 690 | categories = sorted(self._postclosecallback) |
|
681 | 691 | for cat in categories: |
|
682 | 692 | self._postclosecallback[cat](self) |
|
683 | 693 | # Prevent double usage and help clear cycles. |
|
684 | 694 | self._postclosecallback = None |
|
685 | 695 | |
|
686 | 696 | @active |
|
687 | 697 | def abort(self): |
|
688 | 698 | """abort the transaction (generally called on error, or when the |
|
689 | 699 | transaction is not explicitly committed before going out of |
|
690 | 700 | scope)""" |
|
691 | 701 | self._abort() |
|
692 | 702 | |
|
693 | 703 | @active |
|
694 | 704 | def add_journal(self, vfs_id, path): |
|
695 | 705 | self._journal_files.append((vfs_id, path)) |
|
696 | 706 | |
|
697 | 707 | def _writeundo(self): |
|
698 | 708 | """write transaction data for possible future undo call""" |
|
699 | 709 | if self._undoname is None: |
|
700 | 710 | return |
|
701 | 711 | cleanup_undo_files( |
|
702 | 712 | self._report, |
|
703 | 713 | self._vfsmap, |
|
704 | 714 | undo_prefix=self._undoname, |
|
705 | 715 | ) |
|
706 | 716 | |
|
707 | 717 | def undoname(fn: bytes) -> bytes: |
|
708 | 718 | base, name = os.path.split(fn) |
|
709 | 719 | assert name.startswith(self._journal) |
|
710 | 720 | new_name = name.replace(self._journal, self._undoname, 1) |
|
711 | 721 | return os.path.join(base, new_name) |
|
712 | 722 | |
|
713 | 723 | undo_backup_path = b"%s.backupfiles" % self._undoname |
|
714 | 724 | undobackupfile = self._opener.open(undo_backup_path, b'w') |
|
715 | 725 | undobackupfile.write(b'%d\n' % version) |
|
716 | 726 | for l, f, b, c in self._backupentries: |
|
717 | 727 | if not f: # temporary file |
|
718 | 728 | continue |
|
719 | 729 | if not b: |
|
720 | 730 | u = b'' |
|
721 | 731 | else: |
|
722 | 732 | if l not in self._vfsmap and c: |
|
723 | 733 | self._report( |
|
724 | 734 | b"couldn't remove %s: unknown cache location" |
|
725 | 735 | b"%s\n" % (b, l) |
|
726 | 736 | ) |
|
727 | 737 | continue |
|
728 | 738 | vfs = self._vfsmap[l] |
|
729 | 739 | u = undoname(b) |
|
730 | 740 | util.copyfile(vfs.join(b), vfs.join(u), hardlink=True) |
|
731 | 741 | undobackupfile.write(b"%s\0%s\0%s\0%d\n" % (l, f, u, c)) |
|
732 | 742 | undobackupfile.close() |
|
733 | 743 | for vfs, src in self._journal_files: |
|
734 | 744 | dest = undoname(src) |
|
735 | 745 | # if src and dest refer to a same file, vfs.rename is a no-op, |
|
736 | 746 | # leaving both src and dest on disk. delete dest to make sure |
|
737 | 747 | # the rename couldn't be such a no-op. |
|
738 | 748 | vfs.tryunlink(dest) |
|
739 | 749 | try: |
|
740 | 750 | vfs.rename(src, dest) |
|
741 | 751 | except FileNotFoundError: # journal file does not yet exist |
|
742 | 752 | pass |
|
743 | 753 | |
|
744 | 754 | def _abort(self): |
|
745 | 755 | entries = self.readjournal() |
|
746 | 756 | self._count = 0 |
|
747 | 757 | self._usages = 0 |
|
748 | 758 | self._file.close() |
|
749 | 759 | self._backupsfile.close() |
|
750 | 760 | |
|
751 | 761 | quick = self._can_quick_abort(entries) |
|
752 | 762 | try: |
|
753 | 763 | if not quick: |
|
754 | 764 | self._report(_(b"transaction abort!\n")) |
|
755 | 765 | for cat in sorted(self._abortcallback): |
|
756 | 766 | self._abortcallback[cat](self) |
|
757 | 767 | # Prevent double usage and help clear cycles. |
|
758 | 768 | self._abortcallback = None |
|
759 | 769 | if quick: |
|
760 | 770 | self._do_quick_abort(entries) |
|
761 | 771 | else: |
|
762 | 772 | self._do_full_abort(entries) |
|
763 | 773 | finally: |
|
764 | 774 | self._journal = None |
|
765 | 775 | self._releasefn(self, False) # notify failure of transaction |
|
766 | 776 | self._releasefn = None # Help prevent cycles. |
|
767 | 777 | |
|
768 | 778 | def _can_quick_abort(self, entries): |
|
769 | 779 | """False if any semantic content have been written on disk |
|
770 | 780 | |
|
771 | 781 | True if nothing, except temporary files has been writen on disk.""" |
|
772 | 782 | if entries: |
|
773 | 783 | return False |
|
774 | 784 | for e in self._backupentries: |
|
775 | 785 | if e[1]: |
|
776 | 786 | return False |
|
777 | 787 | return True |
|
778 | 788 | |
|
779 | 789 | def _do_quick_abort(self, entries): |
|
780 | 790 | """(Silently) do a quick cleanup (see _can_quick_abort)""" |
|
781 | 791 | assert self._can_quick_abort(entries) |
|
782 | 792 | tmp_files = [e for e in self._backupentries if not e[1]] |
|
783 | 793 | for vfs_id, old_path, tmp_path, xxx in tmp_files: |
|
784 | 794 | vfs = self._vfsmap[vfs_id] |
|
785 | 795 | try: |
|
786 | 796 | vfs.unlink(tmp_path) |
|
787 | 797 | except FileNotFoundError: |
|
788 | 798 | pass |
|
789 | 799 | if self._backupjournal: |
|
790 | 800 | self._opener.unlink(self._backupjournal) |
|
791 | 801 | if self._journal: |
|
792 | 802 | self._opener.unlink(self._journal) |
|
793 | 803 | |
|
794 | 804 | def _do_full_abort(self, entries): |
|
795 | 805 | """(Noisily) rollback all the change introduced by the transaction""" |
|
796 | 806 | try: |
|
797 | 807 | _playback( |
|
798 | 808 | self._journal, |
|
799 | 809 | self._report, |
|
800 | 810 | self._opener, |
|
801 | 811 | self._vfsmap, |
|
802 | 812 | entries, |
|
803 | 813 | self._backupentries, |
|
804 | 814 | False, |
|
805 | 815 | checkambigfiles=self._checkambigfiles, |
|
806 | 816 | ) |
|
807 | 817 | self._report(_(b"rollback completed\n")) |
|
808 | 818 | except BaseException as exc: |
|
809 | 819 | self._report(_(b"rollback failed - please run hg recover\n")) |
|
810 | 820 | self._report( |
|
811 | 821 | _(b"(failure reason: %s)\n") % stringutil.forcebytestr(exc) |
|
812 | 822 | ) |
|
813 | 823 | |
|
814 | 824 | |
|
815 | 825 | BAD_VERSION_MSG = _( |
|
816 | 826 | b"journal was created by a different version of Mercurial\n" |
|
817 | 827 | ) |
|
818 | 828 | |
|
819 | 829 | |
|
820 | 830 | def read_backup_files(report, fp): |
|
821 | 831 | """parse an (already open) backup file an return contained backup entries |
|
822 | 832 | |
|
823 | 833 | entries are in the form: (location, file, backupfile, xxx) |
|
824 | 834 | |
|
825 | 835 | :location: the vfs identifier (vfsmap's key) |
|
826 | 836 | :file: original file path (in the vfs) |
|
827 | 837 | :backupfile: path of the backup (in the vfs) |
|
828 | 838 | :cache: a boolean currently always set to False |
|
829 | 839 | """ |
|
830 | 840 | lines = fp.readlines() |
|
831 | 841 | backupentries = [] |
|
832 | 842 | if lines: |
|
833 | 843 | ver = lines[0][:-1] |
|
834 | 844 | if ver != (b'%d' % version): |
|
835 | 845 | report(BAD_VERSION_MSG) |
|
836 | 846 | else: |
|
837 | 847 | for line in lines[1:]: |
|
838 | 848 | if line: |
|
839 | 849 | # Shave off the trailing newline |
|
840 | 850 | line = line[:-1] |
|
841 | 851 | l, f, b, c = line.split(b'\0') |
|
842 | 852 | backupentries.append((l, f, b, bool(c))) |
|
843 | 853 | return backupentries |
|
844 | 854 | |
|
845 | 855 | |
|
846 | 856 | def rollback( |
|
847 | 857 | opener, |
|
848 | 858 | vfsmap, |
|
849 | 859 | file, |
|
850 | 860 | report, |
|
851 | 861 | checkambigfiles=None, |
|
852 | 862 | skip_journal_pattern=None, |
|
853 | 863 | ): |
|
854 | 864 | """Rolls back the transaction contained in the given file |
|
855 | 865 | |
|
856 | 866 | Reads the entries in the specified file, and the corresponding |
|
857 | 867 | '*.backupfiles' file, to recover from an incomplete transaction. |
|
858 | 868 | |
|
859 | 869 | * `file`: a file containing a list of entries, specifying where |
|
860 | 870 | to truncate each file. The file should contain a list of |
|
861 | 871 | file\0offset pairs, delimited by newlines. The corresponding |
|
862 | 872 | '*.backupfiles' file should contain a list of file\0backupfile |
|
863 | 873 | pairs, delimited by \0. |
|
864 | 874 | |
|
865 | 875 | `checkambigfiles` is a set of (path, vfs-location) tuples, |
|
866 | 876 | which determine whether file stat ambiguity should be avoided at |
|
867 | 877 | restoring corresponded files. |
|
868 | 878 | """ |
|
869 | 879 | entries = [] |
|
870 | 880 | backupentries = [] |
|
871 | 881 | |
|
872 | 882 | with opener.open(file) as fp: |
|
873 | 883 | lines = fp.readlines() |
|
874 | 884 | for l in lines: |
|
875 | 885 | try: |
|
876 | 886 | f, o = l.split(b'\0') |
|
877 | 887 | entries.append((f, int(o))) |
|
878 | 888 | except ValueError: |
|
879 | 889 | report( |
|
880 | 890 | _(b"couldn't read journal entry %r!\n") % pycompat.bytestr(l) |
|
881 | 891 | ) |
|
882 | 892 | |
|
883 | 893 | backupjournal = b"%s.backupfiles" % file |
|
884 | 894 | if opener.exists(backupjournal): |
|
885 | 895 | with opener.open(backupjournal) as fp: |
|
886 | 896 | backupentries = read_backup_files(report, fp) |
|
887 | 897 | if skip_journal_pattern is not None: |
|
888 | 898 | keep = lambda x: not skip_journal_pattern.match(x[1]) |
|
889 | 899 | backupentries = [x for x in backupentries if keep(x)] |
|
890 | 900 | |
|
891 | 901 | _playback( |
|
892 | 902 | file, |
|
893 | 903 | report, |
|
894 | 904 | opener, |
|
895 | 905 | vfsmap, |
|
896 | 906 | entries, |
|
897 | 907 | backupentries, |
|
898 | 908 | checkambigfiles=checkambigfiles, |
|
899 | 909 | ) |
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