From 098aa867626ef2444ef14a92b428a6ca26d83e60 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 17 Feb 2017 17:59:06 +0100 Subject: [PATCH] rev-parse: fix several options when running in a subdirectory In addition to making git_path() aware of certain file names that need to be handled differently e.g. when running in worktrees, the commit 557bd833bb (git_path(): be aware of file relocation in $GIT_DIR, 2014-11-30) also snuck in a new option for `git rev-parse`: `--git-path`. On the face of it, there is no obvious bug in that commit's diff: it faithfully calls git_path() on the argument and prints it out, i.e. `git rev-parse --git-path ` has the same precise behavior as calling `git_path("")` in C. The problem lies deeper, much deeper. In hindsight (which is always unfair), implementing the .git/ directory discovery in `setup_git_directory()` by changing the working directory may have allowed us to avoid passing around a struct that contains information about the current repository, but it bought us many, many problems. In this case, when being called in a subdirectory, `git rev-parse` changes the working directory to the top-level directory before calling `git_path()`. In the new working directory, the result is correct. But in the working directory of the calling script, it is incorrect. Example: when calling `git rev-parse --git-path HEAD` in, say, the Documentation/ subdirectory of Git's own source code, the string `.git/HEAD` is printed. Side note: that bug is hidden when running in a subdirectory of a worktree that was added by the `git worktree` command: in that case, the (correct) absolute path of the `HEAD` file is printed. In the interest of time, this patch does not go the "correct" route to introduce a struct with repository information (and removing global state in the process), instead this patch chooses to detect when the command was called in a subdirectory and forces the result to be an absolute path. While at it, we are also fixing the output of --git-common-dir and --shared-index-path. Lastly, please note that we reuse the same strbuf for all of the relative_path() calls; this avoids frequent allocation (and duplicated code), and it does not risk memory leaks, for two reasons: 1) the cmd_rev_parse() function does not return anywhere between the use of the new strbuf instance and its final release, and 2) git-rev-parse is one of these "one-shot" programs in Git, i.e. it exits after running for a very short time, meaning that all allocated memory is released with the exit() call anyway. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- builtin/rev-parse.c | 15 +++++++++++---- t/t1500-rev-parse.sh | 4 ++-- t/t1700-split-index.sh | 2 +- t/t2027-worktree-list.sh | 4 ++-- 4 files changed, 16 insertions(+), 9 deletions(-) diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c index ff13e59e1d..2cfd8d2aae 100644 --- a/builtin/rev-parse.c +++ b/builtin/rev-parse.c @@ -545,6 +545,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix) unsigned int flags = 0; const char *name = NULL; struct object_context unused; + struct strbuf buf = STRBUF_INIT; if (argc > 1 && !strcmp("--parseopt", argv[1])) return cmd_parseopt(argc - 1, argv + 1, prefix); @@ -599,7 +600,9 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix) if (!strcmp(arg, "--git-path")) { if (!argv[i + 1]) die("--git-path requires an argument"); - puts(git_path("%s", argv[i + 1])); + strbuf_reset(&buf); + puts(relative_path(git_path("%s", argv[i + 1]), + prefix, &buf)); i++; continue; } @@ -821,8 +824,9 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix) continue; } if (!strcmp(arg, "--git-common-dir")) { - const char *pfx = prefix ? prefix : ""; - puts(prefix_filename(pfx, strlen(pfx), get_git_common_dir())); + strbuf_reset(&buf); + puts(relative_path(get_git_common_dir(), + prefix, &buf)); continue; } if (!strcmp(arg, "--is-inside-git-dir")) { @@ -845,7 +849,9 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix) die(_("Could not read the index")); if (the_index.split_index) { const unsigned char *sha1 = the_index.split_index->base_sha1; - puts(git_path("sharedindex.%s", sha1_to_hex(sha1))); + const char *path = git_path("sharedindex.%s", sha1_to_hex(sha1)); + strbuf_reset(&buf); + puts(relative_path(path, prefix, &buf)); } continue; } @@ -897,6 +903,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix) continue; verify_filename(prefix, arg, 1); } + strbuf_release(&buf); if (verify) { if (revs_count == 1) { show_rev(type, sha1, name); diff --git a/t/t1500-rev-parse.sh b/t/t1500-rev-parse.sh index f39f783f2d..d74f09ad93 100755 --- a/t/t1500-rev-parse.sh +++ b/t/t1500-rev-parse.sh @@ -93,7 +93,7 @@ test_expect_success 'git-common-dir from worktree root' ' test_cmp expect actual ' -test_expect_failure 'git-common-dir inside sub-dir' ' +test_expect_success 'git-common-dir inside sub-dir' ' mkdir -p path/to/child && test_when_finished "rm -rf path" && echo "$(git -C path/to/child rev-parse --show-cdup).git" >expect && @@ -107,7 +107,7 @@ test_expect_success 'git-path from worktree root' ' test_cmp expect actual ' -test_expect_failure 'git-path inside sub-dir' ' +test_expect_success 'git-path inside sub-dir' ' mkdir -p path/to/child && test_when_finished "rm -rf path" && echo "$(git -C path/to/child rev-parse --show-cdup).git/objects" >expect && diff --git a/t/t1700-split-index.sh b/t/t1700-split-index.sh index b754865a61..6096f2c630 100755 --- a/t/t1700-split-index.sh +++ b/t/t1700-split-index.sh @@ -200,7 +200,7 @@ EOF test_cmp expect actual ' -test_expect_failure 'rev-parse --shared-index-path' ' +test_expect_success 'rev-parse --shared-index-path' ' test_create_repo split-index && ( cd split-index && diff --git a/t/t2027-worktree-list.sh b/t/t2027-worktree-list.sh index c1a072348e..848da5f368 100755 --- a/t/t2027-worktree-list.sh +++ b/t/t2027-worktree-list.sh @@ -8,7 +8,7 @@ test_expect_success 'setup' ' test_commit init ' -test_expect_failure 'rev-parse --git-common-dir on main worktree' ' +test_expect_success 'rev-parse --git-common-dir on main worktree' ' git rev-parse --git-common-dir >actual && echo .git >expected && test_cmp expected actual && @@ -18,7 +18,7 @@ test_expect_failure 'rev-parse --git-common-dir on main worktree' ' test_cmp expected2 actual2 ' -test_expect_failure 'rev-parse --git-path objects linked worktree' ' +test_expect_success 'rev-parse --git-path objects linked worktree' ' echo "$(git rev-parse --show-toplevel)/.git/objects" >expect && test_when_finished "rm -rf linked-tree && git worktree prune" && git worktree add --detach linked-tree master &&