From a9bcf6586d1a4888aea91553d73cda20494b8335 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Wed, 14 Jun 2017 13:36:00 +0200 Subject: [PATCH] alias: use the early config machinery to expand aliases Instead of discovering the .git/ directory, reading the config and then trying to painstakingly reset all the global state if we did not find a matching alias, let's use the early config machinery instead. It may look like unnecessary work to discover the .git/ directory in the early config machinery and then call setup_git_directory_gently() in the case of a shell alias, repeating the very same discovery *again*. However, we have to do this as the early config machinery takes pains *not* to touch any global state, while shell aliases expect a possibly changed working directory and at least the GIT_PREFIX and GIT_DIR variables to be set. This change also fixes a known issue where Git tried to read the pager config from an incorrect path in a subdirectory of a Git worktree if an alias expanded to a shell command. Signed-off-by: Johannes Schindelin Reviewed-by: Jeff King Signed-off-by: Junio C Hamano --- alias.c | 28 ++++++++++++++++++------ git.c | 55 ++++-------------------------------------------- t/t7006-pager.sh | 2 +- 3 files changed, 26 insertions(+), 59 deletions(-) diff --git a/alias.c b/alias.c index 3b90397a99..0526304661 100644 --- a/alias.c +++ b/alias.c @@ -1,14 +1,28 @@ #include "cache.h" +struct config_alias_data { + const char *alias; + char *v; +}; + +static int config_alias_cb(const char *key, const char *value, void *d) +{ + struct config_alias_data *data = d; + const char *p; + + if (skip_prefix(key, "alias.", &p) && !strcmp(p, data->alias)) + return git_config_string((const char **)&data->v, key, value); + + return 0; +} + char *alias_lookup(const char *alias) { - char *v = NULL; - struct strbuf key = STRBUF_INIT; - strbuf_addf(&key, "alias.%s", alias); - if (git_config_key_is_valid(key.buf)) - git_config_get_string(key.buf, &v); - strbuf_release(&key); - return v; + struct config_alias_data data = { alias, NULL }; + + read_early_config(config_alias_cb, &data); + + return data.v; } #define SPLIT_CMDLINE_BAD_ENDING 1 diff --git a/git.c b/git.c index 8ff44f081d..58ef570294 100644 --- a/git.c +++ b/git.c @@ -16,50 +16,6 @@ const char git_more_info_string[] = "to read about a specific subcommand or concept."); static int use_pager = -1; -static char *orig_cwd; -static const char *env_names[] = { - GIT_DIR_ENVIRONMENT, - GIT_WORK_TREE_ENVIRONMENT, - GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, - GIT_PREFIX_ENVIRONMENT -}; -static char *orig_env[4]; -static int save_restore_env_balance; - -static void save_env_before_alias(void) -{ - int i; - - assert(save_restore_env_balance == 0); - save_restore_env_balance = 1; - orig_cwd = xgetcwd(); - for (i = 0; i < ARRAY_SIZE(env_names); i++) { - orig_env[i] = getenv(env_names[i]); - orig_env[i] = xstrdup_or_null(orig_env[i]); - } -} - -static void restore_env(int external_alias) -{ - int i; - - assert(save_restore_env_balance == 1); - save_restore_env_balance = 0; - if (!external_alias && orig_cwd && chdir(orig_cwd)) - die_errno("could not move to %s", orig_cwd); - free(orig_cwd); - for (i = 0; i < ARRAY_SIZE(env_names); i++) { - if (external_alias && - !strcmp(env_names[i], GIT_PREFIX_ENVIRONMENT)) - continue; - if (orig_env[i]) { - setenv(env_names[i], orig_env[i], 1); - free(orig_env[i]); - } else { - unsetenv(env_names[i]); - } - } -} static void commit_pager_choice(void) { switch (use_pager) { @@ -250,19 +206,18 @@ static int handle_alias(int *argcp, const char ***argv) const char **new_argv; const char *alias_command; char *alias_string; - int unused_nongit; - - save_env_before_alias(); - setup_git_directory_gently(&unused_nongit); alias_command = (*argv)[0]; alias_string = alias_lookup(alias_command); if (alias_string) { if (alias_string[0] == '!') { struct child_process child = CHILD_PROCESS_INIT; + int nongit_ok; + + /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */ + setup_git_directory_gently(&nongit_ok); commit_pager_choice(); - restore_env(1); child.use_shell = 1; argv_array_push(&child.args, alias_string + 1); @@ -308,8 +263,6 @@ static int handle_alias(int *argcp, const char ***argv) ret = 1; } - restore_env(0); - errno = saved_errno; return ret; diff --git a/t/t7006-pager.sh b/t/t7006-pager.sh index 83881ec3a0..20b4d83c28 100755 --- a/t/t7006-pager.sh +++ b/t/t7006-pager.sh @@ -391,7 +391,7 @@ test_expect_success TTY 'core.pager in repo config works and retains cwd' ' ) ' -test_expect_failure TTY 'core.pager is found via alias in subdirectory' ' +test_expect_success TTY 'core.pager is found via alias in subdirectory' ' sane_unset GIT_PAGER && test_config core.pager "cat >via-alias" && ( -- 2.39.2