[PATCH v3 4/4] ref: add symlink ref content check for files backend
- From
shejialuo <shejialuo@gmail.com>
- Date
- Sep 3, 2024, 12:21 UTC
- Message-ID
- <Ztb_Lzxgla2FHICH@ArchLinux>
- In-Reply-To
- <Ztb-mgl50cwGVO8A@ArchLinux>
We have already introduced "files_fsck_symref_target". We should reuse this function to handle the symrefs which use legacy symbolic links. We should not check the trailing garbage for symbolic refs. Add a new parameter "symbolic_link" to disable some checks which should only be executed for textual symrefs.
We firstly use the "strbuf_add_real_path" to resolve the symlink and get the absolute path "referent_path" which the symlink ref points to. Then we can get the absolute path "abs_gitdir" of the "gitdir". By combining "referent_path" and "abs_gitdir", we can extract the "referent". Thus, we can reuse "files_fsck_symref_target" function to seamlessly check the symlink refs.
Because we are going to drop support for "core.prefersymlinkrefs", add a new fsck message "symlinkRef" to let the user be aware of this information.
Mentored-by: Patrick Steinhardt <ps@pks.im> Mentored-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: shejialuo <shejialuo@gmail.com> --- Documentation/fsck-msgids.txt | 5 ++ fsck.h | 1 + refs/files-backend.c | 68 +++++++++++++++++++----- t/t0602-reffiles-fsck.sh | 97 +++++++++++++++++++++++++++++++++++ 4 files changed, 157 insertions(+), 14 deletions(-)
diff --git a/Documentation/fsck-msgids.txt b/Documentation/fsck-msgids.txt index beb6c4e49e..9e8e1ac7f0 100644 --- a/Documentation/fsck-msgids.txt +++ b/Documentation/fsck-msgids.txt @@ -181,6 +181,11 @@ (INFO) A ref does not end with newline. This kind of ref may be considered ERROR in the future. +`symlinkRef`:: + (INFO) A symref uses the symbolic link. This kind of symref may + be considered ERROR in the future when totally dropping the + symlink support. + `trailingRefContent`:: (INFO) A ref has trailing contents. This kind of ref may be considered ERROR in the future. diff --git a/fsck.h b/fsck.h index 5ea874916d..1c6f750812 100644 --- a/fsck.h +++ b/fsck.h @@ -87,6 +87,7 @@ enum fsck_msg_type { FUNC(BAD_TAG_NAME, INFO) \ FUNC(MISSING_TAGGER_ENTRY, INFO) \ FUNC(REF_MISSING_NEWLINE, INFO) \ + FUNC(SYMLINK_REF, INFO) \ FUNC(TRAILING_REF_CONTENT, INFO) \ /* ignored (elevated when requested) */ \ FUNC(EXTRA_HEADER_ENTRY, IGNORE) diff --git a/refs/files-backend.c b/refs/files-backend.c index fef32e607f..2a1b952f0d 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -1,4 +1,5 @@ #include "../git-compat-util.h" +#include "../abspath.h" #include "../copy.h" #include "../environment.h" #include "../gettext.h" @@ -1950,10 +1951,13 @@ static int commit_ref_update(struct files_ref_store *refs, return 0; } +#ifdef NO_SYMLINK_HEAD +#define create_ref_symlink(a, b) (-1) +#else static int create_ref_symlink(struct ref_lock *lock, const char *target) { int ret = -1; -#ifndef NO_SYMLINK_HEAD + char *ref_path = get_locked_file_path(&lock->lk); unlink(ref_path); ret = symlink(target, ref_path); @@ -1961,13 +1965,12 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target) if (ret) fprintf(stderr, "no symlink - falling back to symbolic ref\n"); -#endif return ret; } +#endif -static int create_symref_lock(struct files_ref_store *refs, - struct ref_lock *lock, const char *refname, - const char *target, struct strbuf *err) +static int create_symref_lock(struct ref_lock *lock, const char *target, + struct strbuf *err) { if (!fdopen_lock_file(&lock->lk, "w")) { strbuf_addf(err, "unable to fdopen %s: %s", @@ -2583,8 +2586,7 @@ static int lock_ref_for_update(struct files_ref_store *refs, } if (update->new_target && !(update->flags & REF_LOG_ONLY)) { - if (create_symref_lock(refs, lock, update->refname, - update->new_target, err)) { + if (create_symref_lock(lock, update->new_target, err)) { ret = TRANSACTION_GENERIC_ERROR; goto out; } @@ -3436,12 +3438,15 @@ typedef int (*files_fsck_refs_fn)(struct ref_store *ref_store, /* * Check the symref "referent" and "referent_path". For textual symref, - * "referent" would be the content after "refs:". + * "referent" would be the content after "refs:". For symlink ref, + * "referent" would be the relative path agaignst "gitdir" which should + * be the same as the textual symref literally. */ static int files_fsck_symref_target(struct fsck_options *o, struct fsck_ref_report *report, struct strbuf *referent, - struct strbuf *referent_path) + struct strbuf *referent_path, + unsigned int symbolic_link) { size_t len = referent->len - 1; const char *p = NULL; @@ -3456,14 +3461,16 @@ static int files_fsck_symref_target(struct fsck_options *o, goto out; } - if (referent->buf[referent->len - 1] != '\n') { + if (!symbolic_link && referent->buf[referent->len - 1] != '\n') { ret = fsck_report_ref(o, report, FSCK_MSG_REF_MISSING_NEWLINE, "missing newline"); len++; } - strbuf_rtrim(referent); + if (!symbolic_link) + strbuf_rtrim(referent); + if (check_refname_format(referent->buf, 0)) { ret = fsck_report_ref(o, report, FSCK_MSG_BAD_SYMREF_TARGET, @@ -3471,7 +3478,7 @@ static int files_fsck_symref_target(struct fsck_options *o, goto out; } - if (len != referent->len) { + if (!symbolic_link && len != referent->len) { ret = fsck_report_ref(o, report, FSCK_MSG_TRAILING_REF_CONTENT, "trailing garbage in ref"); @@ -3509,9 +3516,11 @@ static int files_fsck_refs_content(struct ref_store *ref_store, { struct strbuf referent_path = STRBUF_INIT; struct strbuf ref_content = STRBUF_INIT; + struct strbuf abs_gitdir = STRBUF_INIT; struct strbuf referent = STRBUF_INIT; struct strbuf refname = STRBUF_INIT; struct fsck_ref_report report = {0}; + unsigned int symbolic_link = 0; const char *trailing = NULL; unsigned int type = 0; int failure_errno = 0; @@ -3521,8 +3530,37 @@ static int files_fsck_refs_content(struct ref_store *ref_store, strbuf_addf(&refname, "%s/%s", refs_check_dir, iter->relative_path); report.path = refname.buf; - if (S_ISLNK(iter->st.st_mode)) + if (S_ISLNK(iter->st.st_mode)) { + const char* relative_referent_path; + + symbolic_link = 1; + ret = fsck_report_ref(o, &report, + FSCK_MSG_SYMLINK_REF, + "use deprecated symbolic link for symref"); + + strbuf_add_absolute_path(&abs_gitdir, ref_store->gitdir); + strbuf_normalize_path(&abs_gitdir); + if (!is_dir_sep(abs_gitdir.buf[abs_gitdir.len - 1])) + strbuf_addch(&abs_gitdir, '/'); + + strbuf_add_real_path(&referent_path, iter->path.buf); + + if (!skip_prefix(referent_path.buf, + abs_gitdir.buf, + &relative_referent_path)) { + ret = fsck_report_ref(o, &report, + FSCK_MSG_BAD_SYMREF_TARGET, + "point to target outside gitdir"); + goto cleanup; + } + + strbuf_addstr(&referent, relative_referent_path); + ret = files_fsck_symref_target(o, &report, + &referent, &referent_path, + symbolic_link); + goto cleanup; + } if (strbuf_read_file(&ref_content, iter->path.buf, 0) < 0) { ret = error_errno(_("%s/%s: unable to read the ref"), @@ -3563,7 +3601,8 @@ static int files_fsck_refs_content(struct ref_store *ref_store, strbuf_rtrim(&referent_path); ret = files_fsck_symref_target(o, &report, &referent, - &referent_path); + &referent_path, + symbolic_link); } cleanup: @@ -3571,6 +3610,7 @@ static int files_fsck_refs_content(struct ref_store *ref_store, strbuf_release(&ref_content); strbuf_release(&referent); strbuf_release(&referent_path); + strbuf_release(&abs_gitdir); return ret; } diff --git a/t/t0602-reffiles-fsck.sh b/t/t0602-reffiles-fsck.sh index e0bf8c8c8b..e735816d5b 100755 --- a/t/t0602-reffiles-fsck.sh +++ b/t/t0602-reffiles-fsck.sh @@ -326,4 +326,101 @@ test_expect_success 'textual symref content should be checked (aggregate)' ' test_cmp expect sorted_err ' +test_expect_success SYMLINKS 'symlink symref content should be checked (individual)' ' + test_when_finished "rm -rf repo" && + git init repo && + branch_dir_prefix=.git/refs/heads && + tag_dir_prefix=.git/refs/tags && + cd repo && + test_commit default && + mkdir -p "$branch_dir_prefix/a/b" && + + ln -sf ./main $branch_dir_prefix/branch-symbolic-good && + git refs verify 2>err && + cat >expect <<-EOF && + warning: refs/heads/branch-symbolic-good: symlinkRef: use deprecated symbolic link for symref + EOF + rm $branch_dir_prefix/branch-symbolic-good && + test_cmp expect err && + + ln -sf ../../../../branch $branch_dir_prefix/branch-symbolic-1 && + test_must_fail git refs verify 2>err && + cat >expect <<-EOF && + warning: refs/heads/branch-symbolic-1: symlinkRef: use deprecated symbolic link for symref + error: refs/heads/branch-symbolic-1: badSymrefTarget: point to target outside gitdir + EOF + rm $branch_dir_prefix/branch-symbolic-1 && + test_cmp expect err && + + ln -sf ../../logs/branch-bad $branch_dir_prefix/branch-symbolic-2 && + test_must_fail git refs verify 2>err && + cat >expect <<-EOF && + warning: refs/heads/branch-symbolic-2: symlinkRef: use deprecated symbolic link for symref + error: refs/heads/branch-symbolic-2: badSymrefTarget: points to ref outside the refs directory + EOF + rm $branch_dir_prefix/branch-symbolic-2 && + test_cmp expect err && + + ln -sf ./"branch space" $branch_dir_prefix/branch-symbolic-3 && + test_must_fail git refs verify 2>err && + cat >expect <<-EOF && + warning: refs/heads/branch-symbolic-3: symlinkRef: use deprecated symbolic link for symref + error: refs/heads/branch-symbolic-3: badSymrefTarget: points to refname with invalid format + EOF + rm $branch_dir_prefix/branch-symbolic-3 && + test_cmp expect err && + + ln -sf ./".tag" $tag_dir_prefix/tag-symbolic-1 && + test_must_fail git refs verify 2>err && + cat >expect <<-EOF && + warning: refs/tags/tag-symbolic-1: symlinkRef: use deprecated symbolic link for symref + error: refs/tags/tag-symbolic-1: badSymrefTarget: points to refname with invalid format + EOF + rm $tag_dir_prefix/tag-symbolic-1 && + test_cmp expect err && + + ln -sf ./ $tag_dir_prefix/tag-symbolic-2 && + test_must_fail git refs verify 2>err && + cat >expect <<-EOF && + warning: refs/tags/tag-symbolic-2: symlinkRef: use deprecated symbolic link for symref + error: refs/tags/tag-symbolic-2: badSymrefTarget: points to the directory + EOF + rm $tag_dir_prefix/tag-symbolic-2 && + test_cmp expect err +' + +test_expect_success SYMLINKS 'symlink symref content should be checked (aggregate)' ' + test_when_finished "rm -rf repo" && + git init repo && + branch_dir_prefix=.git/refs/heads && + tag_dir_prefix=.git/refs/tags && + cd repo && + test_commit default && + mkdir -p "$branch_dir_prefix/a/b" && + + ln -sf ./main $branch_dir_prefix/branch-symbolic-good && + ln -sf ../../../../branch $branch_dir_prefix/branch-symbolic-1 && + ln -sf ../../logs/branch-bad $branch_dir_prefix/branch-symbolic-2 && + ln -sf ./"branch space" $branch_dir_prefix/branch-symbolic-3 && + ln -sf ./".tag" $tag_dir_prefix/tag-symbolic-1 && + ln -sf ./ $tag_dir_prefix/tag-symbolic-2 && + + test_must_fail git refs verify 2>err && + cat >expect <<-EOF && + error: refs/heads/branch-symbolic-1: badSymrefTarget: point to target outside gitdir + error: refs/heads/branch-symbolic-2: badSymrefTarget: points to ref outside the refs directory + error: refs/heads/branch-symbolic-3: badSymrefTarget: points to refname with invalid format + error: refs/tags/tag-symbolic-1: badSymrefTarget: points to refname with invalid format + error: refs/tags/tag-symbolic-2: badSymrefTarget: points to the directory + warning: refs/heads/branch-symbolic-1: symlinkRef: use deprecated symbolic link for symref + warning: refs/heads/branch-symbolic-2: symlinkRef: use deprecated symbolic link for symref + warning: refs/heads/branch-symbolic-3: symlinkRef: use deprecated symbolic link for symref + warning: refs/heads/branch-symbolic-good: symlinkRef: use deprecated symbolic link for symref + warning: refs/tags/tag-symbolic-1: symlinkRef: use deprecated symbolic link for symref + warning: refs/tags/tag-symbolic-2: symlinkRef: use deprecated symbolic link for symref + EOF + sort err >sorted_err && + test_cmp expect sorted_err +' + test_done
-- 2.46.0