git/builtin/init-db.c
Jeff King 517fe807d6 assert NOARG/NONEG behavior of parse-options callbacks
When we define a parse-options callback, the flags we put in the option
struct must match what the callback expects. For example, a callback
which does not handle the "unset" parameter should only be used with
PARSE_OPT_NONEG. But since the callback and the option struct are not
defined next to each other, it's easy to get this wrong (as earlier
patches in this series show).

Fortunately, the compiler can help us here: compiling with
-Wunused-parameters can show us which callbacks ignore their "unset"
parameters (and likewise, ones that ignore "arg" expect to be triggered
with PARSE_OPT_NOARG).

But after we've inspected a callback and determined that all of its
callers use the right flags, what do we do next? We'd like to silence
the compiler warning, but do so in a way that will catch any wrong calls
in the future.

We can do that by actually checking those variables and asserting that
they match our expectations. Because this is such a common pattern,
we'll introduce some helper macros. The resulting messages aren't
as descriptive as we could make them, but the file/line information from
BUG() is enough to identify the problem (and anyway, the point is that
these should never be seen).

Each of the annotated callbacks in this patch triggers
-Wunused-parameters, and was manually inspected to make sure all callers
use the correct options (so none of these BUGs should be triggerable).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-06 12:56:29 +09:00

589 lines
16 KiB
C

/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.h"
#include "config.h"
#include "refs.h"
#include "builtin.h"
#include "exec-cmd.h"
#include "parse-options.h"
#ifndef DEFAULT_GIT_TEMPLATE_DIR
#define DEFAULT_GIT_TEMPLATE_DIR "/usr/share/git-core/templates"
#endif
#ifdef NO_TRUSTABLE_FILEMODE
#define TEST_FILEMODE 0
#else
#define TEST_FILEMODE 1
#endif
static int init_is_bare_repository = 0;
static int init_shared_repository = -1;
static const char *init_db_template_dir;
static void copy_templates_1(struct strbuf *path, struct strbuf *template_path,
DIR *dir)
{
size_t path_baselen = path->len;
size_t template_baselen = template_path->len;
struct dirent *de;
/* Note: if ".git/hooks" file exists in the repository being
* re-initialized, /etc/core-git/templates/hooks/update would
* cause "git init" to fail here. I think this is sane but
* it means that the set of templates we ship by default, along
* with the way the namespace under .git/ is organized, should
* be really carefully chosen.
*/
safe_create_dir(path->buf, 1);
while ((de = readdir(dir)) != NULL) {
struct stat st_git, st_template;
int exists = 0;
strbuf_setlen(path, path_baselen);
strbuf_setlen(template_path, template_baselen);
if (de->d_name[0] == '.')
continue;
strbuf_addstr(path, de->d_name);
strbuf_addstr(template_path, de->d_name);
if (lstat(path->buf, &st_git)) {
if (errno != ENOENT)
die_errno(_("cannot stat '%s'"), path->buf);
}
else
exists = 1;
if (lstat(template_path->buf, &st_template))
die_errno(_("cannot stat template '%s'"), template_path->buf);
if (S_ISDIR(st_template.st_mode)) {
DIR *subdir = opendir(template_path->buf);
if (!subdir)
die_errno(_("cannot opendir '%s'"), template_path->buf);
strbuf_addch(path, '/');
strbuf_addch(template_path, '/');
copy_templates_1(path, template_path, subdir);
closedir(subdir);
}
else if (exists)
continue;
else if (S_ISLNK(st_template.st_mode)) {
struct strbuf lnk = STRBUF_INIT;
if (strbuf_readlink(&lnk, template_path->buf,
st_template.st_size) < 0)
die_errno(_("cannot readlink '%s'"), template_path->buf);
if (symlink(lnk.buf, path->buf))
die_errno(_("cannot symlink '%s' '%s'"),
lnk.buf, path->buf);
strbuf_release(&lnk);
}
else if (S_ISREG(st_template.st_mode)) {
if (copy_file(path->buf, template_path->buf, st_template.st_mode))
die_errno(_("cannot copy '%s' to '%s'"),
template_path->buf, path->buf);
}
else
error(_("ignoring template %s"), template_path->buf);
}
}
static void copy_templates(const char *template_dir)
{
struct strbuf path = STRBUF_INIT;
struct strbuf template_path = STRBUF_INIT;
size_t template_len;
struct repository_format template_format;
struct strbuf err = STRBUF_INIT;
DIR *dir;
char *to_free = NULL;
if (!template_dir)
template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
if (!template_dir)
template_dir = init_db_template_dir;
if (!template_dir)
template_dir = to_free = system_path(DEFAULT_GIT_TEMPLATE_DIR);
if (!template_dir[0]) {
free(to_free);
return;
}
strbuf_addstr(&template_path, template_dir);
strbuf_complete(&template_path, '/');
template_len = template_path.len;
dir = opendir(template_path.buf);
if (!dir) {
warning(_("templates not found in %s"), template_dir);
goto free_return;
}
/* Make sure that template is from the correct vintage */
strbuf_addstr(&template_path, "config");
read_repository_format(&template_format, template_path.buf);
strbuf_setlen(&template_path, template_len);
/*
* No mention of version at all is OK, but anything else should be
* verified.
*/
if (template_format.version >= 0 &&
verify_repository_format(&template_format, &err) < 0) {
warning(_("not copying templates from '%s': %s"),
template_dir, err.buf);
strbuf_release(&err);
goto close_free_return;
}
strbuf_addstr(&path, get_git_common_dir());
strbuf_complete(&path, '/');
copy_templates_1(&path, &template_path, dir);
close_free_return:
closedir(dir);
free_return:
free(to_free);
strbuf_release(&path);
strbuf_release(&template_path);
}
static int git_init_db_config(const char *k, const char *v, void *cb)
{
if (!strcmp(k, "init.templatedir"))
return git_config_pathname(&init_db_template_dir, k, v);
return 0;
}
/*
* If the git_dir is not directly inside the working tree, then git will not
* find it by default, and we need to set the worktree explicitly.
*/
static int needs_work_tree_config(const char *git_dir, const char *work_tree)
{
if (!strcmp(work_tree, "/") && !strcmp(git_dir, "/.git"))
return 0;
if (skip_prefix(git_dir, work_tree, &git_dir) &&
!strcmp(git_dir, "/.git"))
return 0;
return 1;
}
static int create_default_files(const char *template_path,
const char *original_git_dir)
{
struct stat st1;
struct strbuf buf = STRBUF_INIT;
char *path;
char repo_version_string[10];
char junk[2];
int reinit;
int filemode;
struct strbuf err = STRBUF_INIT;
/* Just look for `init.templatedir` */
git_config(git_init_db_config, NULL);
/*
* First copy the templates -- we might have the default
* config file there, in which case we would want to read
* from it after installing.
*
* Before reading that config, we also need to clear out any cached
* values (since we've just potentially changed what's available on
* disk).
*/
copy_templates(template_path);
git_config_clear();
reset_shared_repository();
git_config(git_default_config, NULL);
/*
* We must make sure command-line options continue to override any
* values we might have just re-read from the config.
*/
is_bare_repository_cfg = init_is_bare_repository;
if (init_shared_repository != -1)
set_shared_repository(init_shared_repository);
/*
* We would have created the above under user's umask -- under
* shared-repository settings, we would need to fix them up.
*/
if (get_shared_repository()) {
adjust_shared_perm(get_git_dir());
}
/*
* We need to create a "refs" dir in any case so that older
* versions of git can tell that this is a repository.
*/
safe_create_dir(git_path("refs"), 1);
adjust_shared_perm(git_path("refs"));
if (refs_init_db(&err))
die("failed to set up refs db: %s", err.buf);
/*
* Create the default symlink from ".git/HEAD" to the "master"
* branch, if it does not exist yet.
*/
path = git_path_buf(&buf, "HEAD");
reinit = (!access(path, R_OK)
|| readlink(path, junk, sizeof(junk)-1) != -1);
if (!reinit) {
if (create_symref("HEAD", "refs/heads/master", NULL) < 0)
exit(1);
}
/* This forces creation of new config file */
xsnprintf(repo_version_string, sizeof(repo_version_string),
"%d", GIT_REPO_VERSION);
git_config_set("core.repositoryformatversion", repo_version_string);
/* Check filemode trustability */
path = git_path_buf(&buf, "config");
filemode = TEST_FILEMODE;
if (TEST_FILEMODE && !lstat(path, &st1)) {
struct stat st2;
filemode = (!chmod(path, st1.st_mode ^ S_IXUSR) &&
!lstat(path, &st2) &&
st1.st_mode != st2.st_mode &&
!chmod(path, st1.st_mode));
if (filemode && !reinit && (st1.st_mode & S_IXUSR))
filemode = 0;
}
git_config_set("core.filemode", filemode ? "true" : "false");
if (is_bare_repository())
git_config_set("core.bare", "true");
else {
const char *work_tree = get_git_work_tree();
git_config_set("core.bare", "false");
/* allow template config file to override the default */
if (log_all_ref_updates == LOG_REFS_UNSET)
git_config_set("core.logallrefupdates", "true");
if (needs_work_tree_config(original_git_dir, work_tree))
git_config_set("core.worktree", work_tree);
}
if (!reinit) {
/* Check if symlink is supported in the work tree */
path = git_path_buf(&buf, "tXXXXXX");
if (!close(xmkstemp(path)) &&
!unlink(path) &&
!symlink("testing", path) &&
!lstat(path, &st1) &&
S_ISLNK(st1.st_mode))
unlink(path); /* good */
else
git_config_set("core.symlinks", "false");
/* Check if the filesystem is case-insensitive */
path = git_path_buf(&buf, "CoNfIg");
if (!access(path, F_OK))
git_config_set("core.ignorecase", "true");
probe_utf8_pathname_composition();
}
strbuf_release(&buf);
return reinit;
}
static void create_object_directory(void)
{
struct strbuf path = STRBUF_INIT;
size_t baselen;
strbuf_addstr(&path, get_object_directory());
baselen = path.len;
safe_create_dir(path.buf, 1);
strbuf_setlen(&path, baselen);
strbuf_addstr(&path, "/pack");
safe_create_dir(path.buf, 1);
strbuf_setlen(&path, baselen);
strbuf_addstr(&path, "/info");
safe_create_dir(path.buf, 1);
strbuf_release(&path);
}
static void separate_git_dir(const char *git_dir, const char *git_link)
{
struct stat st;
if (!stat(git_link, &st)) {
const char *src;
if (S_ISREG(st.st_mode))
src = read_gitfile(git_link);
else if (S_ISDIR(st.st_mode))
src = git_link;
else
die(_("unable to handle file type %d"), (int)st.st_mode);
if (rename(src, git_dir))
die_errno(_("unable to move %s to %s"), src, git_dir);
}
write_file(git_link, "gitdir: %s", git_dir);
}
int init_db(const char *git_dir, const char *real_git_dir,
const char *template_dir, unsigned int flags)
{
int reinit;
int exist_ok = flags & INIT_DB_EXIST_OK;
char *original_git_dir = real_pathdup(git_dir, 1);
if (real_git_dir) {
struct stat st;
if (!exist_ok && !stat(git_dir, &st))
die(_("%s already exists"), git_dir);
if (!exist_ok && !stat(real_git_dir, &st))
die(_("%s already exists"), real_git_dir);
set_git_dir(real_path(real_git_dir));
git_dir = get_git_dir();
separate_git_dir(git_dir, original_git_dir);
}
else {
set_git_dir(real_path(git_dir));
git_dir = get_git_dir();
}
startup_info->have_repository = 1;
safe_create_dir(git_dir, 0);
init_is_bare_repository = is_bare_repository();
/* Check to see if the repository version is right.
* Note that a newly created repository does not have
* config file, so this will not fail. What we are catching
* is an attempt to reinitialize new repository with an old tool.
*/
check_repository_format();
reinit = create_default_files(template_dir, original_git_dir);
create_object_directory();
if (get_shared_repository()) {
char buf[10];
/* We do not spell "group" and such, so that
* the configuration can be read by older version
* of git. Note, we use octal numbers for new share modes,
* and compatibility values for PERM_GROUP and
* PERM_EVERYBODY.
*/
if (get_shared_repository() < 0)
/* force to the mode value */
xsnprintf(buf, sizeof(buf), "0%o", -get_shared_repository());
else if (get_shared_repository() == PERM_GROUP)
xsnprintf(buf, sizeof(buf), "%d", OLD_PERM_GROUP);
else if (get_shared_repository() == PERM_EVERYBODY)
xsnprintf(buf, sizeof(buf), "%d", OLD_PERM_EVERYBODY);
else
BUG("invalid value for shared_repository");
git_config_set("core.sharedrepository", buf);
git_config_set("receive.denyNonFastforwards", "true");
}
if (!(flags & INIT_DB_QUIET)) {
int len = strlen(git_dir);
if (reinit)
printf(get_shared_repository()
? _("Reinitialized existing shared Git repository in %s%s\n")
: _("Reinitialized existing Git repository in %s%s\n"),
git_dir, len && git_dir[len-1] != '/' ? "/" : "");
else
printf(get_shared_repository()
? _("Initialized empty shared Git repository in %s%s\n")
: _("Initialized empty Git repository in %s%s\n"),
git_dir, len && git_dir[len-1] != '/' ? "/" : "");
}
free(original_git_dir);
return 0;
}
static int guess_repository_type(const char *git_dir)
{
const char *slash;
char *cwd;
int cwd_is_git_dir;
/*
* "GIT_DIR=. git init" is always bare.
* "GIT_DIR=`pwd` git init" too.
*/
if (!strcmp(".", git_dir))
return 1;
cwd = xgetcwd();
cwd_is_git_dir = !strcmp(git_dir, cwd);
free(cwd);
if (cwd_is_git_dir)
return 1;
/*
* "GIT_DIR=.git or GIT_DIR=something/.git is usually not.
*/
if (!strcmp(git_dir, ".git"))
return 0;
slash = strrchr(git_dir, '/');
if (slash && !strcmp(slash, "/.git"))
return 0;
/*
* Otherwise it is often bare. At this point
* we are just guessing.
*/
return 1;
}
static int shared_callback(const struct option *opt, const char *arg, int unset)
{
BUG_ON_OPT_NEG(unset);
*((int *) opt->value) = (arg) ? git_config_perm("arg", arg) : PERM_GROUP;
return 0;
}
static const char *const init_db_usage[] = {
N_("git init [-q | --quiet] [--bare] [--template=<template-directory>] [--shared[=<permissions>]] [<directory>]"),
NULL
};
/*
* If you want to, you can share the DB area with any number of branches.
* That has advantages: you can save space by sharing all the SHA1 objects.
* On the other hand, it might just make lookup slower and messier. You
* be the judge. The default case is to have one DB per managed directory.
*/
int cmd_init_db(int argc, const char **argv, const char *prefix)
{
const char *git_dir;
const char *real_git_dir = NULL;
const char *work_tree;
const char *template_dir = NULL;
unsigned int flags = 0;
const struct option init_db_options[] = {
OPT_STRING(0, "template", &template_dir, N_("template-directory"),
N_("directory from which templates will be used")),
OPT_SET_INT(0, "bare", &is_bare_repository_cfg,
N_("create a bare repository"), 1),
{ OPTION_CALLBACK, 0, "shared", &init_shared_repository,
N_("permissions"),
N_("specify that the git repository is to be shared amongst several users"),
PARSE_OPT_OPTARG | PARSE_OPT_NONEG, shared_callback, 0},
OPT_BIT('q', "quiet", &flags, N_("be quiet"), INIT_DB_QUIET),
OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
N_("separate git dir from working tree")),
OPT_END()
};
argc = parse_options(argc, argv, prefix, init_db_options, init_db_usage, 0);
if (real_git_dir && !is_absolute_path(real_git_dir))
real_git_dir = real_pathdup(real_git_dir, 1);
if (argc == 1) {
int mkdir_tried = 0;
retry:
if (chdir(argv[0]) < 0) {
if (!mkdir_tried) {
int saved;
/*
* At this point we haven't read any configuration,
* and we know shared_repository should always be 0;
* but just in case we play safe.
*/
saved = get_shared_repository();
set_shared_repository(0);
switch (safe_create_leading_directories_const(argv[0])) {
case SCLD_OK:
case SCLD_PERMS:
break;
case SCLD_EXISTS:
errno = EEXIST;
/* fallthru */
default:
die_errno(_("cannot mkdir %s"), argv[0]);
break;
}
set_shared_repository(saved);
if (mkdir(argv[0], 0777) < 0)
die_errno(_("cannot mkdir %s"), argv[0]);
mkdir_tried = 1;
goto retry;
}
die_errno(_("cannot chdir to %s"), argv[0]);
}
} else if (0 < argc) {
usage(init_db_usage[0]);
}
if (is_bare_repository_cfg == 1) {
char *cwd = xgetcwd();
setenv(GIT_DIR_ENVIRONMENT, cwd, argc > 0);
free(cwd);
}
if (init_shared_repository != -1)
set_shared_repository(init_shared_repository);
/*
* GIT_WORK_TREE makes sense only in conjunction with GIT_DIR
* without --bare. Catch the error early.
*/
git_dir = getenv(GIT_DIR_ENVIRONMENT);
work_tree = getenv(GIT_WORK_TREE_ENVIRONMENT);
if ((!git_dir || is_bare_repository_cfg == 1) && work_tree)
die(_("%s (or --work-tree=<directory>) not allowed without "
"specifying %s (or --git-dir=<directory>)"),
GIT_WORK_TREE_ENVIRONMENT,
GIT_DIR_ENVIRONMENT);
/*
* Set up the default .git directory contents
*/
if (!git_dir)
git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
if (is_bare_repository_cfg < 0)
is_bare_repository_cfg = guess_repository_type(git_dir);
if (!is_bare_repository_cfg) {
const char *git_dir_parent = strrchr(git_dir, '/');
if (git_dir_parent) {
char *rel = xstrndup(git_dir, git_dir_parent - git_dir);
git_work_tree_cfg = real_pathdup(rel, 1);
free(rel);
}
if (!git_work_tree_cfg)
git_work_tree_cfg = xgetcwd();
if (work_tree)
set_git_work_tree(work_tree);
else
set_git_work_tree(git_work_tree_cfg);
if (access(get_git_work_tree(), X_OK))
die_errno (_("Cannot access work tree '%s'"),
get_git_work_tree());
}
else {
if (work_tree)
set_git_work_tree(work_tree);
}
UNLEAK(real_git_dir);
flags |= INIT_DB_EXIST_OK;
return init_db(git_dir, real_git_dir, template_dir, flags);
}