From a24a273008e03893e9dc84f333f4c565788dc300 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Tue, 24 May 2022 14:39:29 -0400 Subject: [PATCH 1/2] setup: add discover_git_directory_reason() There are many reasons why discovering a Git directory may fail. In particular, 8959555cee7 (setup_git_directory(): add an owner check for the top-level directory, 2022-03-02) added ownership checks as a security precaution. Callers attempting to set up a Git directory may want to inform the user about the reason for the failure. For that, expose the enum discovery_result from within setup.c and into cache.h where discover_git_directory() is defined. I initially wanted to change the return type of discover_git_directory() to be this enum, but several callers rely upon the "zero means success". The two problems with this are: 1. The zero value of the enum is actually GIT_DIR_NONE, so nonpositive results are errors. 2. There are multiple successful states, so some positive results are successful. Instead of updating all callers immediately, add a new method, discover_git_directory_reason(), and convert discover_git_directory() to be a thin shim on top of it. Because there are extra checks that discover_git_directory_reason() does after setup_git_directory_gently_1(), there are other modes that can be returned for failure states. Add these modes to the enum, but be sure to explicitly add them as BUG() states in the switch of setup_git_directory_gently(). Signed-off-by: Derrick Stolee --- setup.c | 32 +++++++++++--------------------- setup.h | 32 ++++++++++++++++++++++++++++++-- 2 files changed, 41 insertions(+), 23 deletions(-) diff --git a/setup.c b/setup.c index 761b4d674b6e26..70f272b666ed9d 100644 --- a/setup.c +++ b/setup.c @@ -1212,19 +1212,6 @@ static const char *allowed_bare_repo_to_string( return NULL; } -enum discovery_result { - GIT_DIR_NONE = 0, - GIT_DIR_EXPLICIT, - GIT_DIR_DISCOVERED, - GIT_DIR_BARE, - /* these are errors */ - GIT_DIR_HIT_CEILING = -1, - GIT_DIR_HIT_MOUNT_POINT = -2, - GIT_DIR_INVALID_GITFILE = -3, - GIT_DIR_INVALID_OWNERSHIP = -4, - GIT_DIR_DISALLOWED_BARE = -5, -}; - /* * We cannot decide in this function whether we are in the work tree or * not, since the config can only be read _after_ this function was called. @@ -1376,21 +1363,22 @@ static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir, } } -int discover_git_directory(struct strbuf *commondir, - struct strbuf *gitdir) +enum discovery_result discover_git_directory_reason(struct strbuf *commondir, + struct strbuf *gitdir) { struct strbuf dir = STRBUF_INIT, err = STRBUF_INIT; size_t gitdir_offset = gitdir->len, cwd_len; size_t commondir_offset = commondir->len; struct repository_format candidate = REPOSITORY_FORMAT_INIT; + enum discovery_result result; if (strbuf_getcwd(&dir)) - return -1; + return GIT_DIR_CWD_FAILURE; cwd_len = dir.len; - if (setup_git_directory_gently_1(&dir, gitdir, NULL, 0) <= 0) { + if ((result = setup_git_directory_gently_1(&dir, gitdir, NULL, 0)) <= 0) { strbuf_release(&dir); - return -1; + return result; } /* @@ -1420,7 +1408,7 @@ int discover_git_directory(struct strbuf *commondir, strbuf_setlen(commondir, commondir_offset); strbuf_setlen(gitdir, gitdir_offset); clear_repository_format(&candidate); - return -1; + return GIT_DIR_INVALID_FORMAT; } /* take ownership of candidate.partial_clone */ @@ -1429,7 +1417,7 @@ int discover_git_directory(struct strbuf *commondir, candidate.partial_clone = NULL; clear_repository_format(&candidate); - return 0; + return result; } const char *setup_git_directory_gently(int *nongit_ok) @@ -1521,9 +1509,11 @@ const char *setup_git_directory_gently(int *nongit_ok) *nongit_ok = 1; break; case GIT_DIR_NONE: + case GIT_DIR_CWD_FAILURE: + case GIT_DIR_INVALID_FORMAT: /* * As a safeguard against setup_git_directory_gently_1 returning - * this value, fallthrough to BUG. Otherwise it is possible to + * these values, fallthrough to BUG. Otherwise it is possible to * set startup_info->have_repository to 1 when we did nothing to * find a repository. */ diff --git a/setup.h b/setup.h index 4c1ca9d0c94b88..dd4adc815d09d2 100644 --- a/setup.h +++ b/setup.h @@ -42,6 +42,30 @@ const char *resolve_gitdir_gently(const char *suspect, int *return_error_code); #define resolve_gitdir(path) resolve_gitdir_gently((path), NULL) void setup_work_tree(void); + +/* + * discover_git_directory_reason() is similar to discover_git_directory(), + * except it returns an enum value instead. It is important to note that + * a zero-valued return here is actually GIT_DIR_NONE, which is different + * from discover_git_directory. + */ +enum discovery_result { + GIT_DIR_NONE = 0, + GIT_DIR_EXPLICIT, + GIT_DIR_DISCOVERED, + GIT_DIR_BARE, + /* these are errors */ + GIT_DIR_HIT_CEILING = -1, + GIT_DIR_HIT_MOUNT_POINT = -2, + GIT_DIR_INVALID_GITFILE = -3, + GIT_DIR_INVALID_OWNERSHIP = -4, + GIT_DIR_DISALLOWED_BARE = -5, + GIT_DIR_INVALID_FORMAT = -6, + GIT_DIR_CWD_FAILURE = -7, +}; +enum discovery_result discover_git_directory_reason(struct strbuf *commondir, + struct strbuf *gitdir); + /* * Find the commondir and gitdir of the repository that contains the current * working directory, without changing the working directory or other global @@ -50,8 +74,12 @@ void setup_work_tree(void); * both have the same result appended to the buffer. The return value is * either 0 upon success and non-zero if no repository was found. */ -int discover_git_directory(struct strbuf *commondir, - struct strbuf *gitdir); +static inline int discover_git_directory(struct strbuf *commondir, + struct strbuf *gitdir) +{ + return discover_git_directory_reason(commondir, gitdir) <= 0; +} + const char *setup_git_directory_gently(int *); const char *setup_git_directory(void); char *prefix_path(const char *prefix, int len, const char *path); From 959ba03909908b1612e474548e5d97c1d48ddbd9 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Mon, 23 May 2022 10:56:35 -0400 Subject: [PATCH 2/2] scalar reconfigure: help users remove buggy repos When running 'scalar reconfigure -a', such as at install time, Scalar has warning messages about the repository missing (or not containing a .git directory). Failures can also happen while trying to modify the repository-local config for that repository. These warnings may seem confusing to users who don't understand what they mean or how to stop them. Add a warning that instructs the user how to remove the warning in future installations. Signed-off-by: Derrick Stolee --- scalar.c | 56 +++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 39 insertions(+), 17 deletions(-) diff --git a/scalar.c b/scalar.c index c86ba32a4a4fcf..dc0bcaf7485050 100644 --- a/scalar.c +++ b/scalar.c @@ -1032,6 +1032,7 @@ static int cmd_reconfigure(int argc, const char **argv) git_config(get_scalar_repos, &scalar_repos); for (i = 0; i < scalar_repos.nr; i++) { + int failed = 0; const char *dir = scalar_repos.items[i].string; strbuf_reset(&commondir); @@ -1042,30 +1043,51 @@ static int cmd_reconfigure(int argc, const char **argv) if (errno != ENOENT) { warning_errno(_("could not switch to '%s'"), dir); - res = -1; - continue; + failed = -1; + goto loop_end; } strbuf_addstr(&buf, dir); if (remove_deleted_enlistment(&buf)) - res = error(_("could not remove stale " - "scalar.repo '%s'"), dir); + failed = error(_("could not remove stale " + "scalar.repo '%s'"), dir); else - warning(_("removing stale scalar.repo '%s'"), + warning(_("removed stale scalar.repo '%s'"), dir); strbuf_release(&buf); - } else if (discover_git_directory(&commondir, &gitdir) < 0) { - warning_errno(_("git repository gone in '%s'"), dir); - res = -1; - } else { - git_config_clear(); - - the_repository = &r; - r.commondir = commondir.buf; - r.gitdir = gitdir.buf; - - if (set_recommended_config(1) < 0) - res = -1; + goto loop_end; + } + + switch (discover_git_directory_reason(&commondir, &gitdir)) { + case GIT_DIR_INVALID_OWNERSHIP: + warning(_("repository at '%s' has different owner"), dir); + failed = -1; + goto loop_end; + + case GIT_DIR_DISCOVERED: + break; + + default: + warning(_("repository not found in '%s'"), dir); + failed = -1; + break; + } + + git_config_clear(); + + the_repository = &r; + r.commondir = commondir.buf; + r.gitdir = gitdir.buf; + + if (set_recommended_config(1) < 0) + failed = -1; + +loop_end: + if (failed) { + res = failed; + warning(_("to unregister this repository from Scalar, run\n" + "\tgit config --global --unset --fixed-value scalar.repo \"%s\""), + dir); } }