| Message ID | ec036c04d1b003385683f0ed1dec80cc3bbfb813.1708983566.git.gitgitgadget@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 29c139ce7895e1c14be119300a7f99fbdc90c5e1 |
| Headers | show |
| Series | FSMonitor edge cases on case-insensitive file systems | expand |
On Mon, Feb 26, 2024 at 09:39:25PM +0000, Jeff Hostetler via GitGitGadget wrote: > From: Jeff Hostetler <jeffhostetler@github.com> > > Teach fsmonitor_refresh_callback() to handle case-insensitive > lookups if case-sensitive lookups fail on case-insensitive systems. > This can cause 'git status' to report stale status for files if there > are case issues/errors in the worktree. > > The FSMonitor daemon sends FSEvents using the observed spelling > of each pathname. On case-insensitive file systems this may be > different than the expected case spelling. > > The existing code uses index_name_pos() to find the cache-entry for > the pathname in the FSEvent and clear the CE_FSMONITOR_VALID bit so > that the worktree scan/index refresh will revisit and revalidate the > path. > > On a case-insensitive file system, the exact match lookup may fail > to find the associated cache-entry. This causes status to think that > the cached CE flags are correct and skip over the file. > > Update event handling to optionally use the name-hash and dir-name-hash > if necessary. > > Also update t7527 to convert the "test_expect_failure" to "_success" > now that we have fixed the bug. > > Signed-off-by: Jeff Hostetler <jeffhostetler@github.com> > --- > fsmonitor.c | 121 +++++++++++++++++++++++++++++++++++ > t/t7527-builtin-fsmonitor.sh | 26 +++++--- > 2 files changed, 137 insertions(+), 10 deletions(-) > > diff --git a/fsmonitor.c b/fsmonitor.c > index 3c87449be87..2b17d60bbbe 100644 > --- a/fsmonitor.c > +++ b/fsmonitor.c > @@ -5,6 +5,7 @@ > #include "ewah/ewok.h" > #include "fsmonitor.h" > #include "fsmonitor-ipc.h" > +#include "name-hash.h" > #include "run-command.h" > #include "strbuf.h" > #include "trace2.h" > @@ -202,6 +203,113 @@ static void invalidate_ce_fsm(struct cache_entry *ce) > static size_t handle_path_with_trailing_slash( > struct index_state *istate, const char *name, int pos); > > +/* > + * Use the name-hash to do a case-insensitive cache-entry lookup with > + * the pathname and invalidate the cache-entry. > + * > + * Returns the number of cache-entries that we invalidated. > + */ > +static size_t handle_using_name_hash_icase( > + struct index_state *istate, const char *name) > +{ > + struct cache_entry *ce = NULL; > + > + ce = index_file_exists(istate, name, strlen(name), 1); > + if (!ce) > + return 0; > + > + /* > + * A case-insensitive search in the name-hash using the > + * observed pathname found a cache-entry, so the observed path > + * is case-incorrect. Invalidate the cache-entry and use the > + * correct spelling from the cache-entry to invalidate the > + * untracked-cache. Since we now have sparse-directories in > + * the index, the observed pathname may represent a regular > + * file or a sparse-index directory. > + * > + * Note that we should not have seen FSEvents for a > + * sparse-index directory, but we handle it just in case. > + * > + * Either way, we know that there are not any cache-entries for > + * children inside the cone of the directory, so we don't need to > + * do the usual scan. > + */ > + trace_printf_key(&trace_fsmonitor, > + "fsmonitor_refresh_callback MAP: '%s' '%s'", > + name, ce->name); > + > + /* > + * NEEDSWORK: We used the name-hash to find the correct > + * case-spelling of the pathname in the cache-entry[], so > + * technically this is a tracked file or a sparse-directory. > + * It should not have any entries in the untracked-cache, so > + * we should not need to use the case-corrected spelling to > + * invalidate the the untracked-cache. So we may not need to > + * do this. For now, I'm going to be conservative and always > + * do it; we can revisit this later. > + */ > + untracked_cache_invalidate_trimmed_path(istate, ce->name, 0); > + > + invalidate_ce_fsm(ce); > + return 1; > +} > + > +/* > + * Use the dir-name-hash to find the correct-case spelling of the > + * directory. Use the canonical spelling to invalidate all of the > + * cache-entries within the matching cone. > + * > + * Returns the number of cache-entries that we invalidated. > + */ > +static size_t handle_using_dir_name_hash_icase( > + struct index_state *istate, const char *name) > +{ > + struct strbuf canonical_path = STRBUF_INIT; > + int pos; > + size_t len = strlen(name); > + size_t nr_in_cone; > + > + if (name[len - 1] == '/') > + len--; Nit: this could use `strip_suffix()`. > + > + if (!index_dir_find(istate, name, len, &canonical_path)) > + return 0; /* name is untracked */ > + > + if (!memcmp(name, canonical_path.buf, canonical_path.len)) { > + strbuf_release(&canonical_path); > + /* > + * NEEDSWORK: Our caller already tried an exact match > + * and failed to find one. They called us to do an > + * ICASE match, so we should never get an exact match, > + * so we could promote this to a BUG() here if we > + * wanted to. It doesn't hurt anything to just return Nit: this comment is stale as this has been promoted to a BUG already. Patrick > + * 0 and go on because we should never get here. Or we > + * could just get rid of the memcmp() and this "if" > + * clause completely. > + */ > + BUG("handle_using_dir_name_hash_icase(%s) did not exact match", > + name); > + } > + > + trace_printf_key(&trace_fsmonitor, > + "fsmonitor_refresh_callback MAP: '%s' '%s'", > + name, canonical_path.buf); > + > + /* > + * The dir-name-hash only tells us the corrected spelling of > + * the prefix. We have to use this canonical path to do a > + * lookup in the cache-entry array so that we repeat the > + * original search using the case-corrected spelling. > + */ > + strbuf_addch(&canonical_path, '/'); > + pos = index_name_pos(istate, canonical_path.buf, > + canonical_path.len); > + nr_in_cone = handle_path_with_trailing_slash( > + istate, canonical_path.buf, pos); > + strbuf_release(&canonical_path); > + return nr_in_cone; > +} > + > /* > * The daemon sent an observed pathname without a trailing slash. > * (This is the normal case.) We do not know if it is a tracked or > @@ -335,6 +443,19 @@ static void fsmonitor_refresh_callback(struct index_state *istate, char *name) > else > nr_in_cone = handle_path_without_trailing_slash(istate, name, pos); > > + /* > + * If we did not find an exact match for this pathname or any > + * cache-entries with this directory prefix and we're on a > + * case-insensitive file system, try again using the name-hash > + * and dir-name-hash. > + */ > + if (!nr_in_cone && ignore_case) { > + nr_in_cone = handle_using_name_hash_icase(istate, name); > + if (!nr_in_cone) > + nr_in_cone = handle_using_dir_name_hash_icase( > + istate, name); > + } > + > if (nr_in_cone) > trace_printf_key(&trace_fsmonitor, > "fsmonitor_refresh_callback CNT: %d", > diff --git a/t/t7527-builtin-fsmonitor.sh b/t/t7527-builtin-fsmonitor.sh > index 830f2d9de33..730f3c7f810 100755 > --- a/t/t7527-builtin-fsmonitor.sh > +++ b/t/t7527-builtin-fsmonitor.sh > @@ -1051,7 +1051,7 @@ test_expect_success 'split-index and FSMonitor work well together' ' > # > # The setup is a little contrived. > # > -test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor subdir case wrong on disk' ' > +test_expect_success CASE_INSENSITIVE_FS 'fsmonitor subdir case wrong on disk' ' > test_when_finished "stop_daemon_delete_repo subdir_case_wrong" && > > git init subdir_case_wrong && > @@ -1116,19 +1116,19 @@ test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor subdir case wrong on disk' ' > > grep -q "dir1/DIR2/dir3/file3.*pos -3" "$PWD/subdir_case_wrong.log1" && > > + # Verify that we get a mapping event to correct the case. > + grep -q "MAP:.*dir1/DIR2/dir3/file3.*dir1/dir2/dir3/file3" \ > + "$PWD/subdir_case_wrong.log1" && > + > # The refresh-callbacks should have caused "git status" to clear > # the CE_FSMONITOR_VALID bit on each of those files and caused > # the worktree scan to visit them and mark them as modified. > grep -q " M AAA" "$PWD/subdir_case_wrong.out" && > grep -q " M zzz" "$PWD/subdir_case_wrong.out" && > - > - # Expect Breakage: with the case confusion, the "(pos -3)" causes > - # the client to not clear the CE_FSMONITOR_VALID bit and therefore > - # status will not rescan the file and therefore not report it as dirty. > grep -q " M dir1/dir2/dir3/file3" "$PWD/subdir_case_wrong.out" > ' > > -test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor file case wrong on disk' ' > +test_expect_success CASE_INSENSITIVE_FS 'fsmonitor file case wrong on disk' ' > test_when_finished "stop_daemon_delete_repo file_case_wrong" && > > git init file_case_wrong && > @@ -1242,14 +1242,20 @@ test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor file case wrong on disk' ' > GIT_TRACE_FSMONITOR="$PWD/file_case_wrong-try3.log" \ > git -C file_case_wrong --no-optional-locks status --short \ > >"$PWD/file_case_wrong-try3.out" && > + > + # Verify that we get a mapping event to correct the case. > + grep -q "fsmonitor_refresh_callback MAP:.*dir1/dir2/dir3/FILE-3-A.*dir1/dir2/dir3/file-3-a" \ > + "$PWD/file_case_wrong-try3.log" && > + grep -q "fsmonitor_refresh_callback MAP:.*dir1/dir2/dir4/file-4-a.*dir1/dir2/dir4/FILE-4-A" \ > + "$PWD/file_case_wrong-try3.log" && > + > # FSEvents are in observed case. > grep -q "fsmonitor_refresh_callback.*FILE-3-A.*pos -3" "$PWD/file_case_wrong-try3.log" && > grep -q "fsmonitor_refresh_callback.*file-4-a.*pos -9" "$PWD/file_case_wrong-try3.log" && > > - # Expect Breakage: with the case confusion, the "(pos-3)" and > - # "(pos -9)" causes the client to not clear the CE_FSMONITOR_VALID > - # bit and therefore status will not rescan the files and therefore > - # not report them as dirty. > + # The refresh-callbacks should have caused "git status" to clear > + # the CE_FSMONITOR_VALID bit on each of those files and caused > + # the worktree scan to visit them and mark them as modified. > grep -q " M dir1/dir2/dir3/file-3-a" "$PWD/file_case_wrong-try3.out" && > grep -q " M dir1/dir2/dir4/FILE-4-A" "$PWD/file_case_wrong-try3.out" > ' > -- > gitgitgadget
diff --git a/fsmonitor.c b/fsmonitor.c index 3c87449be87..2b17d60bbbe 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -5,6 +5,7 @@ #include "ewah/ewok.h" #include "fsmonitor.h" #include "fsmonitor-ipc.h" +#include "name-hash.h" #include "run-command.h" #include "strbuf.h" #include "trace2.h" @@ -202,6 +203,113 @@ static void invalidate_ce_fsm(struct cache_entry *ce) static size_t handle_path_with_trailing_slash( struct index_state *istate, const char *name, int pos); +/* + * Use the name-hash to do a case-insensitive cache-entry lookup with + * the pathname and invalidate the cache-entry. + * + * Returns the number of cache-entries that we invalidated. + */ +static size_t handle_using_name_hash_icase( + struct index_state *istate, const char *name) +{ + struct cache_entry *ce = NULL; + + ce = index_file_exists(istate, name, strlen(name), 1); + if (!ce) + return 0; + + /* + * A case-insensitive search in the name-hash using the + * observed pathname found a cache-entry, so the observed path + * is case-incorrect. Invalidate the cache-entry and use the + * correct spelling from the cache-entry to invalidate the + * untracked-cache. Since we now have sparse-directories in + * the index, the observed pathname may represent a regular + * file or a sparse-index directory. + * + * Note that we should not have seen FSEvents for a + * sparse-index directory, but we handle it just in case. + * + * Either way, we know that there are not any cache-entries for + * children inside the cone of the directory, so we don't need to + * do the usual scan. + */ + trace_printf_key(&trace_fsmonitor, + "fsmonitor_refresh_callback MAP: '%s' '%s'", + name, ce->name); + + /* + * NEEDSWORK: We used the name-hash to find the correct + * case-spelling of the pathname in the cache-entry[], so + * technically this is a tracked file or a sparse-directory. + * It should not have any entries in the untracked-cache, so + * we should not need to use the case-corrected spelling to + * invalidate the the untracked-cache. So we may not need to + * do this. For now, I'm going to be conservative and always + * do it; we can revisit this later. + */ + untracked_cache_invalidate_trimmed_path(istate, ce->name, 0); + + invalidate_ce_fsm(ce); + return 1; +} + +/* + * Use the dir-name-hash to find the correct-case spelling of the + * directory. Use the canonical spelling to invalidate all of the + * cache-entries within the matching cone. + * + * Returns the number of cache-entries that we invalidated. + */ +static size_t handle_using_dir_name_hash_icase( + struct index_state *istate, const char *name) +{ + struct strbuf canonical_path = STRBUF_INIT; + int pos; + size_t len = strlen(name); + size_t nr_in_cone; + + if (name[len - 1] == '/') + len--; + + if (!index_dir_find(istate, name, len, &canonical_path)) + return 0; /* name is untracked */ + + if (!memcmp(name, canonical_path.buf, canonical_path.len)) { + strbuf_release(&canonical_path); + /* + * NEEDSWORK: Our caller already tried an exact match + * and failed to find one. They called us to do an + * ICASE match, so we should never get an exact match, + * so we could promote this to a BUG() here if we + * wanted to. It doesn't hurt anything to just return + * 0 and go on because we should never get here. Or we + * could just get rid of the memcmp() and this "if" + * clause completely. + */ + BUG("handle_using_dir_name_hash_icase(%s) did not exact match", + name); + } + + trace_printf_key(&trace_fsmonitor, + "fsmonitor_refresh_callback MAP: '%s' '%s'", + name, canonical_path.buf); + + /* + * The dir-name-hash only tells us the corrected spelling of + * the prefix. We have to use this canonical path to do a + * lookup in the cache-entry array so that we repeat the + * original search using the case-corrected spelling. + */ + strbuf_addch(&canonical_path, '/'); + pos = index_name_pos(istate, canonical_path.buf, + canonical_path.len); + nr_in_cone = handle_path_with_trailing_slash( + istate, canonical_path.buf, pos); + strbuf_release(&canonical_path); + return nr_in_cone; +} + /* * The daemon sent an observed pathname without a trailing slash. * (This is the normal case.) We do not know if it is a tracked or @@ -335,6 +443,19 @@ static void fsmonitor_refresh_callback(struct index_state *istate, char *name) else nr_in_cone = handle_path_without_trailing_slash(istate, name, pos); + /* + * If we did not find an exact match for this pathname or any + * cache-entries with this directory prefix and we're on a + * case-insensitive file system, try again using the name-hash + * and dir-name-hash. + */ + if (!nr_in_cone && ignore_case) { + nr_in_cone = handle_using_name_hash_icase(istate, name); + if (!nr_in_cone) + nr_in_cone = handle_using_dir_name_hash_icase( + istate, name); + } + if (nr_in_cone) trace_printf_key(&trace_fsmonitor, "fsmonitor_refresh_callback CNT: %d", diff --git a/t/t7527-builtin-fsmonitor.sh b/t/t7527-builtin-fsmonitor.sh index 830f2d9de33..730f3c7f810 100755 --- a/t/t7527-builtin-fsmonitor.sh +++ b/t/t7527-builtin-fsmonitor.sh @@ -1051,7 +1051,7 @@ test_expect_success 'split-index and FSMonitor work well together' ' # # The setup is a little contrived. # -test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor subdir case wrong on disk' ' +test_expect_success CASE_INSENSITIVE_FS 'fsmonitor subdir case wrong on disk' ' test_when_finished "stop_daemon_delete_repo subdir_case_wrong" && git init subdir_case_wrong && @@ -1116,19 +1116,19 @@ test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor subdir case wrong on disk' ' grep -q "dir1/DIR2/dir3/file3.*pos -3" "$PWD/subdir_case_wrong.log1" && + # Verify that we get a mapping event to correct the case. + grep -q "MAP:.*dir1/DIR2/dir3/file3.*dir1/dir2/dir3/file3" \ + "$PWD/subdir_case_wrong.log1" && + # The refresh-callbacks should have caused "git status" to clear # the CE_FSMONITOR_VALID bit on each of those files and caused # the worktree scan to visit them and mark them as modified. grep -q " M AAA" "$PWD/subdir_case_wrong.out" && grep -q " M zzz" "$PWD/subdir_case_wrong.out" && - - # Expect Breakage: with the case confusion, the "(pos -3)" causes - # the client to not clear the CE_FSMONITOR_VALID bit and therefore - # status will not rescan the file and therefore not report it as dirty. grep -q " M dir1/dir2/dir3/file3" "$PWD/subdir_case_wrong.out" ' -test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor file case wrong on disk' ' +test_expect_success CASE_INSENSITIVE_FS 'fsmonitor file case wrong on disk' ' test_when_finished "stop_daemon_delete_repo file_case_wrong" && git init file_case_wrong && @@ -1242,14 +1242,20 @@ test_expect_failure CASE_INSENSITIVE_FS 'fsmonitor file case wrong on disk' ' GIT_TRACE_FSMONITOR="$PWD/file_case_wrong-try3.log" \ git -C file_case_wrong --no-optional-locks status --short \ >"$PWD/file_case_wrong-try3.out" && + + # Verify that we get a mapping event to correct the case. + grep -q "fsmonitor_refresh_callback MAP:.*dir1/dir2/dir3/FILE-3-A.*dir1/dir2/dir3/file-3-a" \ + "$PWD/file_case_wrong-try3.log" && + grep -q "fsmonitor_refresh_callback MAP:.*dir1/dir2/dir4/file-4-a.*dir1/dir2/dir4/FILE-4-A" \ + "$PWD/file_case_wrong-try3.log" && + # FSEvents are in observed case. grep -q "fsmonitor_refresh_callback.*FILE-3-A.*pos -3" "$PWD/file_case_wrong-try3.log" && grep -q "fsmonitor_refresh_callback.*file-4-a.*pos -9" "$PWD/file_case_wrong-try3.log" && - # Expect Breakage: with the case confusion, the "(pos-3)" and - # "(pos -9)" causes the client to not clear the CE_FSMONITOR_VALID - # bit and therefore status will not rescan the files and therefore - # not report them as dirty. + # The refresh-callbacks should have caused "git status" to clear + # the CE_FSMONITOR_VALID bit on each of those files and caused + # the worktree scan to visit them and mark them as modified. grep -q " M dir1/dir2/dir3/file-3-a" "$PWD/file_case_wrong-try3.out" && grep -q " M dir1/dir2/dir4/FILE-4-A" "$PWD/file_case_wrong-try3.out" '