@matheusbsbs / matheus-bagliano / commits / 2cd83d10bb

setup: suppress implicit "." work-tree for bare repos

If an explicit GIT_DIR is given without a working tree, we implicitly assume that the current working directory should be used as the working tree. E.g.,: GIT_DIR=/some/repo.git git status would compare against the cwd. Unfortunately, we fool this rule for sub-invocations of git by setting GIT_DIR internally ourselves. For example: git init foo cd foo/.git git status ;# fails, as we expect git config alias.st status git status ;# does not fail, but should What happens is that we run setup_git_directory when doing alias lookup (since we need to see the config), set GIT_DIR as a result, and then leave GIT_WORK_TREE blank (because we do not have one). Then when we actually run the status command, we do setup_git_directory again, which sees our explicit GIT_DIR and uses the cwd as an implicit worktree. It's tempting to argue that we should be suppressing that second invocation of setup_git_directory, as it could use the values we already found in memory. However, the problem still exists for sub-processes (e.g., if "git status" were an external command). You can see another example with the "--bare" option, which sets GIT_DIR explicitly. For example: git init foo cd foo/.git git status ;# fails git --bare status ;# does NOT fail We need some way of telling sub-processes "even though GIT_DIR is set, do not use cwd as an implicit working tree". We could do it by putting a special token into GIT_WORK_TREE, but the obvious choice (an empty string) has some portability problems. Instead, we add a new boolean variable, GIT_IMPLICIT_WORK_TREE, which suppresses the use of cwd as a working tree when GIT_DIR is set. We trigger the new variable when we know we are in a bare setting. The variable is left intentionally undocumented, as this is an internal detail (for now, anyway). If somebody comes up with a good alternate use for it, and once we are confident we have shaken any bugs out of it, we can consider promoting it further. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Mar 8, 2013 at 04:32 UTC 2cd83d10bb6bcf768129e1c4e5a4dee4b6bcd27f

5 files changed +41

cache.h

+12

@@ -365,6 +365,18 @@ static inline enum object_type object_type(unsigned int mode)

365 #define GIT_NOTES_REWRITE_REF_ENVIRONMENT "GIT_NOTES_REWRITE_REF"

366 #define GIT_NOTES_REWRITE_MODE_ENVIRONMENT "GIT_NOTES_REWRITE_MODE"

367

368 +/*

369 + * This environment variable is expected to contain a boolean indicating

370 + * whether we should or should not treat:

371 + *

372 + * GIT_DIR=foo.git git ...

373 + *

374 + * as if GIT_WORK_TREE=. was given. It's not expected that users will make use

375 + * of this, but we use it internally to communicate to sub-processes that we

376 + * are in a bare repo. If not set, defaults to true.

377 + */

378 +#define GIT_IMPLICIT_WORK_TREE_ENVIRONMENT "GIT_IMPLICIT_WORK_TREE"

379 +

380 /*

381 * Repository-local GIT_* environment variables; these will be cleared

382 * when git spawns a sub-process that runs inside another repository.

environment.c

@@ -85,6 +85,7 @@ const char * const local_repo_env[] = {

85 DB_ENVIRONMENT,

86 GIT_DIR_ENVIRONMENT,

87 GIT_WORK_TREE_ENVIRONMENT,

88 + GIT_IMPLICIT_WORK_TREE_ENVIRONMENT,

89 GRAFT_ENVIRONMENT,

90 INDEX_ENVIRONMENT,

91 NO_REPLACE_OBJECTS_ENVIRONMENT,

git.c

@@ -125,6 +125,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)

125 static char git_dir[PATH_MAX+1];

126 is_bare_repository_cfg = 1;

127 setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);

128 + setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);

129 if (envchanged)

130 *envchanged = 1;

131 } else if (!strcmp(cmd, "-c")) {

setup.c

@@ -497,6 +497,12 @@ static const char *setup_explicit_git_dir(const char *gitdirenv,

497 set_git_work_tree(core_worktree);

498 }

499 }

500 + else if (!git_env_bool(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, 1)) {

501 + /* #16d */

502 + set_git_dir(gitdirenv);

503 + free(gitfile);

504 + return NULL;

505 + }

506 else /* #2, #10 */

507 set_git_work_tree(".");

508

@@ -575,6 +581,8 @@ static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongi

581 if (check_repository_format_gently(".", nongit_ok))

582 return NULL;

583

584 + setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);

585 +

586 /* --work-tree is set without --git-dir; use discovered one */

587 if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {

588 const char *gitdir;

t/t1510-repo-setup.sh

+19

@@ -517,6 +517,25 @@ test_expect_success '#16c: bare .git has no worktree' '

517 "$here/16c/.git" "(null)" "$here/16c/sub" "(null)"

518 '

519

520 +test_expect_success '#16d: bareness preserved across alias' '

521 + setup_repo 16d unset "" unset &&

522 + (

523 + cd 16d/.git &&

524 + test_must_fail git status &&

525 + git config alias.st status &&

526 + test_must_fail git st

527 + )

528 +'

529 +

530 +test_expect_success '#16e: bareness preserved by --bare' '

531 + setup_repo 16e unset "" unset &&

532 + (

533 + cd 16e/.git &&

534 + test_must_fail git status &&

535 + test_must_fail git --bare status

536 + )

537 +'

538 +

539 test_expect_success '#17: GIT_WORK_TREE without explicit GIT_DIR is accepted (bare case)' '

540 # Just like #16.

541 setup_repo 17a unset "" true &&