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* db/delta-applier: vcs-svn: cap number of bytes read from sliding view test-svn-fe: split off "test-svn-fe -d" into a separate function vcs-svn: let deltas use data from preimage vcs-svn: let deltas use data from postimage vcs-svn: verify that deltas consume all inline data vcs-svn: implement copyfrom_data delta instruction vcs-svn: read instructions from deltas vcs-svn: read inline data from deltas vcs-svn: read the preimage when applying deltas vcs-svn: parse svndiff0 window header vcs-svn: skeleton of an svn delta parser vcs-svn: make buffer_read_binary API more convenient vcs-svn: learn to maintain a sliding view of a file Makefile: list one vcs-svn/xdiff object or header per line Conflicts: Makefile vcs-svn/LICENSEmaint
Jonathan Nieder
14 years ago
10 changed files with 753 additions and 25 deletions
@ -0,0 +1,248 @@
@@ -0,0 +1,248 @@
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#!/bin/sh |
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test_description='test parsing of svndiff0 files |
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Using the "test-svn-fe -d" helper, check that svn-fe correctly |
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interprets deltas using various facilities (some from the spec, |
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some only learned from practice). |
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' |
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. ./test-lib.sh |
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>empty |
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printf foo >preimage |
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test_expect_success 'reject empty delta' ' |
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test_must_fail test-svn-fe -d preimage empty 0 |
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' |
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test_expect_success 'delta can empty file' ' |
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printf "SVNQ" | q_to_nul >clear.delta && |
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test-svn-fe -d preimage clear.delta 4 >actual && |
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test_cmp empty actual |
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' |
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test_expect_success 'reject svndiff2' ' |
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printf "SVN\002" >bad.filetype && |
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test_must_fail test-svn-fe -d preimage bad.filetype 4 |
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' |
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test_expect_success 'one-window empty delta' ' |
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printf "SVNQ%s" "QQQQQ" | q_to_nul >clear.onewindow && |
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test-svn-fe -d preimage clear.onewindow 9 >actual && |
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test_cmp empty actual |
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' |
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|
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test_expect_success 'reject incomplete window header' ' |
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printf "SVNQ%s" "QQQQQ" | q_to_nul >clear.onewindow && |
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printf "SVNQ%s" "QQ" | q_to_nul >clear.partialwindow && |
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test_must_fail test-svn-fe -d preimage clear.onewindow 6 && |
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test_must_fail test-svn-fe -d preimage clear.partialwindow 6 |
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' |
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test_expect_success 'reject declared delta longer than actual delta' ' |
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printf "SVNQ%s" "QQQQQ" | q_to_nul >clear.onewindow && |
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printf "SVNQ%s" "QQ" | q_to_nul >clear.partialwindow && |
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test_must_fail test-svn-fe -d preimage clear.onewindow 14 && |
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test_must_fail test-svn-fe -d preimage clear.partialwindow 9 |
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' |
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test_expect_success 'two-window empty delta' ' |
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printf "SVNQ%s%s" "QQQQQ" "QQQQQ" | q_to_nul >clear.twowindow && |
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test-svn-fe -d preimage clear.twowindow 14 >actual && |
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test_must_fail test-svn-fe -d preimage clear.twowindow 13 && |
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test_cmp empty actual |
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' |
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test_expect_success 'noisy zeroes' ' |
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printf "SVNQ%s" \ |
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"RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRQQQQQ" | |
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tr R "\200" | |
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q_to_nul >clear.noisy && |
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len=$(wc -c <clear.noisy) && |
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test-svn-fe -d preimage clear.noisy $len && |
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test_cmp empty actual |
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' |
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test_expect_success 'reject variable-length int in magic' ' |
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printf "SVNRQ" | tr R "\200" | q_to_nul >clear.badmagic && |
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test_must_fail test-svn-fe -d preimage clear.badmagic 5 |
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' |
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test_expect_success 'reject truncated integer' ' |
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printf "SVNQ%s%s" "QQQQQ" "QQQQRRQ" | |
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tr R "\200" | |
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q_to_nul >clear.fullint && |
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printf "SVNQ%s%s" "QQQQQ" "QQQQRR" | |
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tr RT "\201" | |
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q_to_nul >clear.partialint && |
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test_must_fail test-svn-fe -d preimage clear.fullint 15 && |
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test-svn-fe -d preimage clear.fullint 16 && |
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test_must_fail test-svn-fe -d preimage clear.partialint 15 |
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' |
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test_expect_success 'nonempty (but unused) preimage view' ' |
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printf "SVNQ%b" "Q\003QQQ" | q_to_nul >clear.readpreimage && |
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test-svn-fe -d preimage clear.readpreimage 9 >actual && |
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test_cmp empty actual |
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' |
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test_expect_success 'preimage view: right endpoint cannot backtrack' ' |
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printf "SVNQ%b%b" "Q\003QQQ" "Q\002QQQ" | |
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q_to_nul >clear.backtrack && |
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test_must_fail test-svn-fe -d preimage clear.backtrack 14 |
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' |
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test_expect_success 'preimage view: left endpoint can advance' ' |
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printf "SVNQ%b%b" "Q\003QQQ" "\001\002QQQ" | |
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q_to_nul >clear.preshrink && |
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printf "SVNQ%b%b" "Q\003QQQ" "\001\001QQQ" | |
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q_to_nul >clear.shrinkbacktrack && |
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test-svn-fe -d preimage clear.preshrink 14 >actual && |
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test_must_fail test-svn-fe -d preimage clear.shrinkbacktrack 14 && |
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test_cmp empty actual |
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' |
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test_expect_success 'preimage view: offsets compared by value' ' |
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printf "SVNQ%b%b" "\001\001QQQ" "\0200Q\003QQQ" | |
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q_to_nul >clear.noisybacktrack && |
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printf "SVNQ%b%b" "\001\001QQQ" "\0200\001\002QQQ" | |
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q_to_nul >clear.noisyadvance && |
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test_must_fail test-svn-fe -d preimage clear.noisybacktrack 15 && |
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test-svn-fe -d preimage clear.noisyadvance 15 && |
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test_cmp empty actual |
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' |
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test_expect_success 'preimage view: reject truncated preimage' ' |
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printf "SVNQ%b" "\010QQQQ" | q_to_nul >clear.lateemptyread && |
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printf "SVNQ%b" "\010\001QQQ" | q_to_nul >clear.latenonemptyread && |
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printf "SVNQ%b" "\001\010QQQ" | q_to_nul >clear.longread && |
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test_must_fail test-svn-fe -d preimage clear.lateemptyread 9 && |
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test_must_fail test-svn-fe -d preimage clear.latenonemptyread 9 && |
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test_must_fail test-svn-fe -d preimage clear.longread 9 |
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' |
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test_expect_success 'forbid unconsumed inline data' ' |
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printf "SVNQ%b%s%b%s" "QQQQ\003" "bar" "QQQQ\001" "x" | |
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q_to_nul >inline.clear && |
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test_must_fail test-svn-fe -d preimage inline.clear 18 >actual |
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' |
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test_expect_success 'reject truncated inline data' ' |
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printf "SVNQ%b%s" "QQQQ\003" "b" | q_to_nul >inline.trunc && |
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test_must_fail test-svn-fe -d preimage inline.trunc 10 |
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' |
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test_expect_success 'reject truncated inline data (after instruction section)' ' |
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printf "SVNQ%b%b%s" "QQ\001\001\003" "\0201" "b" | q_to_nul >insn.trunc && |
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test_must_fail test-svn-fe -d preimage insn.trunc 11 |
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' |
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test_expect_success 'copyfrom_data' ' |
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echo hi >expect && |
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printf "SVNQ%b%b%b" "QQ\003\001\003" "\0203" "hi\n" | q_to_nul >copydat && |
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test-svn-fe -d preimage copydat 13 >actual && |
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test_cmp expect actual |
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' |
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test_expect_success 'multiple copyfrom_data' ' |
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echo hi >expect && |
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printf "SVNQ%b%b%b%b%b" "QQ\003\002\003" "\0201\0202" "hi\n" \ |
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"QQQ\002Q" "\0200Q" | q_to_nul >copy.multi && |
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len=$(wc -c <copy.multi) && |
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test-svn-fe -d preimage copy.multi $len >actual && |
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test_cmp expect actual |
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' |
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test_expect_success 'incomplete multiple insn' ' |
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printf "SVNQ%b%b%b" "QQ\003\002\003" "\0203\0200" "hi\n" | |
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q_to_nul >copy.partial && |
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len=$(wc -c <copy.partial) && |
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test_must_fail test-svn-fe -d preimage copy.partial $len |
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' |
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test_expect_success 'catch attempt to copy missing data' ' |
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printf "SVNQ%b%b%s%b%s" "QQ\002\002\001" "\0201\0201" "X" \ |
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"QQQQ\002" "YZ" | |
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q_to_nul >copy.incomplete && |
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len=$(wc -c <copy.incomplete) && |
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test_must_fail test-svn-fe -d preimage copy.incomplete $len |
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' |
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|
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test_expect_success 'copyfrom target to repeat data' ' |
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printf foofoo >expect && |
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printf "SVNQ%b%b%s" "QQ\006\004\003" "\0203\0100\003Q" "foo" | |
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q_to_nul >copytarget.repeat && |
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len=$(wc -c <copytarget.repeat) && |
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test-svn-fe -d preimage copytarget.repeat $len >actual && |
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test_cmp expect actual |
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' |
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test_expect_success 'copyfrom target out of order' ' |
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printf foooof >expect && |
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printf "SVNQ%b%b%s" \ |
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"QQ\006\007\003" "\0203\0101\002\0101\001\0101Q" "foo" | |
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q_to_nul >copytarget.reverse && |
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len=$(wc -c <copytarget.reverse) && |
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test-svn-fe -d preimage copytarget.reverse $len >actual && |
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test_cmp expect actual |
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' |
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test_expect_success 'catch copyfrom future' ' |
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printf "SVNQ%b%b%s" "QQ\004\004\003" "\0202\0101\002\0201" "XYZ" | |
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q_to_nul >copytarget.infuture && |
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len=$(wc -c <copytarget.infuture) && |
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test_must_fail test-svn-fe -d preimage copytarget.infuture $len |
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' |
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test_expect_success 'copy to sustain' ' |
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printf XYXYXYXYXYXZ >expect && |
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printf "SVNQ%b%b%s" "QQ\014\004\003" "\0202\0111Q\0201" "XYZ" | |
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q_to_nul >copytarget.sustain && |
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len=$(wc -c <copytarget.sustain) && |
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test-svn-fe -d preimage copytarget.sustain $len >actual && |
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test_cmp expect actual |
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' |
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|
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test_expect_success 'catch copy that overflows' ' |
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printf "SVNQ%b%b%s" "QQ\003\003\001" "\0201\0177Q" X | |
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q_to_nul >copytarget.overflow && |
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len=$(wc -c <copytarget.overflow) && |
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test_must_fail test-svn-fe -d preimage copytarget.overflow $len |
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' |
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test_expect_success 'copyfrom source' ' |
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printf foo >expect && |
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printf "SVNQ%b%b" "Q\003\003\002Q" "\003Q" | q_to_nul >copysource.all && |
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test-svn-fe -d preimage copysource.all 11 >actual && |
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test_cmp expect actual |
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' |
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test_expect_success 'copy backwards' ' |
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printf oof >expect && |
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printf "SVNQ%b%b" "Q\003\003\006Q" "\001\002\001\001\001Q" | |
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q_to_nul >copysource.rev && |
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test-svn-fe -d preimage copysource.rev 15 >actual && |
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test_cmp expect actual |
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' |
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|
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test_expect_success 'offsets are relative to window' ' |
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printf fo >expect && |
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printf "SVNQ%b%b%b%b" "Q\003\001\002Q" "\001Q" \ |
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"\002\001\001\002Q" "\001Q" | |
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q_to_nul >copysource.two && |
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test-svn-fe -d preimage copysource.two 18 >actual && |
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test_cmp expect actual |
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' |
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test_expect_success 'example from notes/svndiff' ' |
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printf aaaaccccdddddddd >expect && |
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printf aaaabbbbcccc >source && |
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printf "SVNQ%b%b%s" "Q\014\020\007\001" \ |
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"\004Q\004\010\0201\0107\010" d | |
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q_to_nul >delta.example && |
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len=$(wc -c <delta.example) && |
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test-svn-fe -d source delta.example $len >actual && |
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test_cmp expect actual |
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' |
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test_done |
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@ -0,0 +1,79 @@
@@ -0,0 +1,79 @@
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/* |
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* Licensed under a two-clause BSD-style license. |
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* See LICENSE for details. |
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*/ |
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#include "git-compat-util.h" |
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#include "sliding_window.h" |
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#include "line_buffer.h" |
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#include "strbuf.h" |
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static int input_error(struct line_buffer *file) |
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{ |
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if (!buffer_ferror(file)) |
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return error("delta preimage ends early"); |
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return error("cannot read delta preimage: %s", strerror(errno)); |
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} |
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static int skip_or_whine(struct line_buffer *file, off_t gap) |
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{ |
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if (buffer_skip_bytes(file, gap) != gap) |
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return input_error(file); |
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return 0; |
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} |
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static int read_to_fill_or_whine(struct line_buffer *file, |
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struct strbuf *buf, size_t width) |
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{ |
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buffer_read_binary(file, buf, width - buf->len); |
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if (buf->len != width) |
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return input_error(file); |
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return 0; |
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} |
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static int check_overflow(off_t a, size_t b) |
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{ |
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if (b > maximum_signed_value_of_type(off_t)) |
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return error("unrepresentable length in delta: " |
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"%"PRIuMAX" > OFF_MAX", (uintmax_t) b); |
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if (signed_add_overflows(a, (off_t) b)) |
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return error("unrepresentable offset in delta: " |
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"%"PRIuMAX" + %"PRIuMAX" > OFF_MAX", |
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(uintmax_t) a, (uintmax_t) b); |
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return 0; |
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} |
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int move_window(struct sliding_view *view, off_t off, size_t width) |
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{ |
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off_t file_offset; |
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assert(view); |
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assert(view->width <= view->buf.len); |
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assert(!check_overflow(view->off, view->buf.len)); |
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if (check_overflow(off, width)) |
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return -1; |
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if (off < view->off || off + width < view->off + view->width) |
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return error("invalid delta: window slides left"); |
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if (view->max_off >= 0 && view->max_off < off + width) |
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return error("delta preimage ends early"); |
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file_offset = view->off + view->buf.len; |
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if (off < file_offset) { |
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/* Move the overlapping region into place. */ |
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strbuf_remove(&view->buf, 0, off - view->off); |
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} else { |
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/* Seek ahead to skip the gap. */ |
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if (skip_or_whine(view->file, off - file_offset)) |
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return -1; |
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strbuf_setlen(&view->buf, 0); |
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} |
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if (view->buf.len > width) |
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; /* Already read. */ |
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else if (read_to_fill_or_whine(view->file, &view->buf, width)) |
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return -1; |
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view->off = off; |
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view->width = width; |
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return 0; |
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} |
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@ -0,0 +1,18 @@
@@ -0,0 +1,18 @@
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#ifndef SLIDING_WINDOW_H_ |
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#define SLIDING_WINDOW_H_ |
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#include "strbuf.h" |
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struct sliding_view { |
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struct line_buffer *file; |
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off_t off; |
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size_t width; |
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off_t max_off; /* -1 means unlimited */ |
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struct strbuf buf; |
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}; |
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#define SLIDING_VIEW_INIT(input, len) { (input), 0, 0, (len), STRBUF_INIT } |
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extern int move_window(struct sliding_view *view, off_t off, size_t width); |
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#endif |
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@ -0,0 +1,308 @@
@@ -0,0 +1,308 @@
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/* |
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* Licensed under a two-clause BSD-style license. |
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* See LICENSE for details. |
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*/ |
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#include "git-compat-util.h" |
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#include "sliding_window.h" |
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#include "line_buffer.h" |
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#include "svndiff.h" |
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/* |
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* svndiff0 applier |
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* |
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* See http://svn.apache.org/repos/asf/subversion/trunk/notes/svndiff. |
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* |
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* svndiff0 ::= 'SVN\0' window* |
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* window ::= int int int int int instructions inline_data; |
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* instructions ::= instruction*; |
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* instruction ::= view_selector int int |
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* | copyfrom_data int |
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* | packed_view_selector int |
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* | packed_copyfrom_data |
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* ; |
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* view_selector ::= copyfrom_source |
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* | copyfrom_target |
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* ; |
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* copyfrom_source ::= # binary 00 000000; |
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* copyfrom_target ::= # binary 01 000000; |
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* copyfrom_data ::= # binary 10 000000; |
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* packed_view_selector ::= # view_selector OR-ed with 6 bit value; |
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* packed_copyfrom_data ::= # copyfrom_data OR-ed with 6 bit value; |
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* int ::= highdigit* lowdigit; |
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* highdigit ::= # binary 1000 0000 OR-ed with 7 bit value; |
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* lowdigit ::= # 7 bit value; |
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*/ |
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#define INSN_MASK 0xc0 |
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#define INSN_COPYFROM_SOURCE 0x00 |
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#define INSN_COPYFROM_TARGET 0x40 |
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#define INSN_COPYFROM_DATA 0x80 |
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#define OPERAND_MASK 0x3f |
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#define VLI_CONTINUE 0x80 |
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#define VLI_DIGIT_MASK 0x7f |
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#define VLI_BITS_PER_DIGIT 7 |
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struct window { |
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struct sliding_view *in; |
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struct strbuf out; |
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struct strbuf instructions; |
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struct strbuf data; |
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}; |
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#define WINDOW_INIT(w) { (w), STRBUF_INIT, STRBUF_INIT, STRBUF_INIT } |
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static void window_release(struct window *ctx) |
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{ |
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strbuf_release(&ctx->out); |
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strbuf_release(&ctx->instructions); |
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strbuf_release(&ctx->data); |
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} |
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static int write_strbuf(struct strbuf *sb, FILE *out) |
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{ |
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if (fwrite(sb->buf, 1, sb->len, out) == sb->len) /* Success. */ |
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return 0; |
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return error("cannot write delta postimage: %s", strerror(errno)); |
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} |
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|
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static int error_short_read(struct line_buffer *input) |
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{ |
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if (buffer_ferror(input)) |
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return error("error reading delta: %s", strerror(errno)); |
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return error("invalid delta: unexpected end of file"); |
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} |
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static int read_chunk(struct line_buffer *delta, off_t *delta_len, |
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struct strbuf *buf, size_t len) |
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{ |
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strbuf_reset(buf); |
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if (len > *delta_len || |
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buffer_read_binary(delta, buf, len) != len) |
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return error_short_read(delta); |
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*delta_len -= buf->len; |
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return 0; |
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} |
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static int read_magic(struct line_buffer *in, off_t *len) |
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{ |
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static const char magic[] = {'S', 'V', 'N', '\0'}; |
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struct strbuf sb = STRBUF_INIT; |
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if (read_chunk(in, len, &sb, sizeof(magic))) { |
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strbuf_release(&sb); |
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return -1; |
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} |
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if (memcmp(sb.buf, magic, sizeof(magic))) { |
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strbuf_release(&sb); |
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return error("invalid delta: unrecognized file type"); |
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} |
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strbuf_release(&sb); |
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return 0; |
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} |
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static int read_int(struct line_buffer *in, uintmax_t *result, off_t *len) |
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{ |
||||
uintmax_t rv = 0; |
||||
off_t sz; |
||||
for (sz = *len; sz; sz--) { |
||||
const int ch = buffer_read_char(in); |
||||
if (ch == EOF) |
||||
break; |
||||
|
||||
rv <<= VLI_BITS_PER_DIGIT; |
||||
rv += (ch & VLI_DIGIT_MASK); |
||||
if (ch & VLI_CONTINUE) |
||||
continue; |
||||
|
||||
*result = rv; |
||||
*len = sz - 1; |
||||
return 0; |
||||
} |
||||
return error_short_read(in); |
||||
} |
||||
|
||||
static int parse_int(const char **buf, size_t *result, const char *end) |
||||
{ |
||||
size_t rv = 0; |
||||
const char *pos; |
||||
for (pos = *buf; pos != end; pos++) { |
||||
unsigned char ch = *pos; |
||||
|
||||
rv <<= VLI_BITS_PER_DIGIT; |
||||
rv += (ch & VLI_DIGIT_MASK); |
||||
if (ch & VLI_CONTINUE) |
||||
continue; |
||||
|
||||
*result = rv; |
||||
*buf = pos + 1; |
||||
return 0; |
||||
} |
||||
return error("invalid delta: unexpected end of instructions section"); |
||||
} |
||||
|
||||
static int read_offset(struct line_buffer *in, off_t *result, off_t *len) |
||||
{ |
||||
uintmax_t val; |
||||
if (read_int(in, &val, len)) |
||||
return -1; |
||||
if (val > maximum_signed_value_of_type(off_t)) |
||||
return error("unrepresentable offset in delta: %"PRIuMAX"", val); |
||||
*result = val; |
||||
return 0; |
||||
} |
||||
|
||||
static int read_length(struct line_buffer *in, size_t *result, off_t *len) |
||||
{ |
||||
uintmax_t val; |
||||
if (read_int(in, &val, len)) |
||||
return -1; |
||||
if (val > SIZE_MAX) |
||||
return error("unrepresentable length in delta: %"PRIuMAX"", val); |
||||
*result = val; |
||||
return 0; |
||||
} |
||||
|
||||
static int copyfrom_source(struct window *ctx, const char **instructions, |
||||
size_t nbytes, const char *insns_end) |
||||
{ |
||||
size_t offset; |
||||
if (parse_int(instructions, &offset, insns_end)) |
||||
return -1; |
||||
if (unsigned_add_overflows(offset, nbytes) || |
||||
offset + nbytes > ctx->in->width) |
||||
return error("invalid delta: copies source data outside view"); |
||||
strbuf_add(&ctx->out, ctx->in->buf.buf + offset, nbytes); |
||||
return 0; |
||||
} |
||||
|
||||
static int copyfrom_target(struct window *ctx, const char **instructions, |
||||
size_t nbytes, const char *instructions_end) |
||||
{ |
||||
size_t offset; |
||||
if (parse_int(instructions, &offset, instructions_end)) |
||||
return -1; |
||||
if (offset >= ctx->out.len) |
||||
return error("invalid delta: copies from the future"); |
||||
for (; nbytes > 0; nbytes--) |
||||
strbuf_addch(&ctx->out, ctx->out.buf[offset++]); |
||||
return 0; |
||||
} |
||||
|
||||
static int copyfrom_data(struct window *ctx, size_t *data_pos, size_t nbytes) |
||||
{ |
||||
const size_t pos = *data_pos; |
||||
if (unsigned_add_overflows(pos, nbytes) || |
||||
pos + nbytes > ctx->data.len) |
||||
return error("invalid delta: copies unavailable inline data"); |
||||
strbuf_add(&ctx->out, ctx->data.buf + pos, nbytes); |
||||
*data_pos += nbytes; |
||||
return 0; |
||||
} |
||||
|
||||
static int parse_first_operand(const char **buf, size_t *out, const char *end) |
||||
{ |
||||
size_t result = (unsigned char) *(*buf)++ & OPERAND_MASK; |
||||
if (result) { /* immediate operand */ |
||||
*out = result; |
||||
return 0; |
||||
} |
||||
return parse_int(buf, out, end); |
||||
} |
||||
|
||||
static int execute_one_instruction(struct window *ctx, |
||||
const char **instructions, size_t *data_pos) |
||||
{ |
||||
unsigned int instruction; |
||||
const char *insns_end = ctx->instructions.buf + ctx->instructions.len; |
||||
size_t nbytes; |
||||
assert(ctx); |
||||
assert(instructions && *instructions); |
||||
assert(data_pos); |
||||
|
||||
instruction = (unsigned char) **instructions; |
||||
if (parse_first_operand(instructions, &nbytes, insns_end)) |
||||
return -1; |
||||
switch (instruction & INSN_MASK) { |
||||
case INSN_COPYFROM_SOURCE: |
||||
return copyfrom_source(ctx, instructions, nbytes, insns_end); |
||||
case INSN_COPYFROM_TARGET: |
||||
return copyfrom_target(ctx, instructions, nbytes, insns_end); |
||||
case INSN_COPYFROM_DATA: |
||||
return copyfrom_data(ctx, data_pos, nbytes); |
||||
default: |
||||
return error("invalid delta: unrecognized instruction"); |
||||
} |
||||
} |
||||
|
||||
static int apply_window_in_core(struct window *ctx) |
||||
{ |
||||
const char *instructions; |
||||
size_t data_pos = 0; |
||||
|
||||
/* |
||||
* Fill ctx->out.buf using data from the source, target, |
||||
* and inline data views. |
||||
*/ |
||||
for (instructions = ctx->instructions.buf; |
||||
instructions != ctx->instructions.buf + ctx->instructions.len; |
||||
) |
||||
if (execute_one_instruction(ctx, &instructions, &data_pos)) |
||||
return -1; |
||||
if (data_pos != ctx->data.len) |
||||
return error("invalid delta: does not copy all inline data"); |
||||
return 0; |
||||
} |
||||
|
||||
static int apply_one_window(struct line_buffer *delta, off_t *delta_len, |
||||
struct sliding_view *preimage, FILE *out) |
||||
{ |
||||
struct window ctx = WINDOW_INIT(preimage); |
||||
size_t out_len; |
||||
size_t instructions_len; |
||||
size_t data_len; |
||||
assert(delta_len); |
||||
|
||||
/* "source view" offset and length already handled; */ |
||||
if (read_length(delta, &out_len, delta_len) || |
||||
read_length(delta, &instructions_len, delta_len) || |
||||
read_length(delta, &data_len, delta_len) || |
||||
read_chunk(delta, delta_len, &ctx.instructions, instructions_len) || |
||||
read_chunk(delta, delta_len, &ctx.data, data_len)) |
||||
goto error_out; |
||||
strbuf_grow(&ctx.out, out_len); |
||||
if (apply_window_in_core(&ctx)) |
||||
goto error_out; |
||||
if (ctx.out.len != out_len) { |
||||
error("invalid delta: incorrect postimage length"); |
||||
goto error_out; |
||||
} |
||||
if (write_strbuf(&ctx.out, out)) |
||||
goto error_out; |
||||
window_release(&ctx); |
||||
return 0; |
||||
error_out: |
||||
window_release(&ctx); |
||||
return -1; |
||||
} |
||||
|
||||
int svndiff0_apply(struct line_buffer *delta, off_t delta_len, |
||||
struct sliding_view *preimage, FILE *postimage) |
||||
{ |
||||
assert(delta && preimage && postimage); |
||||
|
||||
if (read_magic(delta, &delta_len)) |
||||
return -1; |
||||
while (delta_len) { /* For each window: */ |
||||
off_t pre_off; |
||||
size_t pre_len; |
||||
|
||||
if (read_offset(delta, &pre_off, &delta_len) || |
||||
read_length(delta, &pre_len, &delta_len) || |
||||
move_window(preimage, pre_off, pre_len) || |
||||
apply_one_window(delta, &delta_len, preimage, postimage)) |
||||
return -1; |
||||
} |
||||
return 0; |
||||
} |
||||
Loading…
Reference in new issue