git/builtin/init-db.c
Torsten Bögershausen 76759c7dff git on Mac OS and precomposed unicode
Mac OS X mangles file names containing unicode on file systems HFS+,
VFAT or SAMBA.  When a file using unicode code points outside ASCII
is created on a HFS+ drive, the file name is converted into
decomposed unicode and written to disk. No conversion is done if
the file name is already decomposed unicode.

Calling open("\xc3\x84", ...) with a precomposed "Ä" yields the same
result as open("\x41\xcc\x88",...) with a decomposed "Ä".

As a consequence, readdir() returns the file names in decomposed
unicode, even if the user expects precomposed unicode.  Unlike on
HFS+, Mac OS X stores files on a VFAT drive (e.g. an USB drive) in
precomposed unicode, but readdir() still returns file names in
decomposed unicode.  When a git repository is stored on a network
share using SAMBA, file names are send over the wire and written to
disk on the remote system in precomposed unicode, but Mac OS X
readdir() returns decomposed unicode to be compatible with its
behaviour on HFS+ and VFAT.

The unicode decomposition causes many problems:

- The names "git add" and other commands get from the end user may
  often be precomposed form (the decomposed form is not easily input
  from the keyboard), but when the commands read from the filesystem
  to see what it is going to update the index with already is on the
  filesystem, readdir() will give decomposed form, which is different.

- Similarly "git log", "git mv" and all other commands that need to
  compare pathnames found on the command line (often but not always
  precomposed form; a command line input resulting from globbing may
  be in decomposed) with pathnames found in the tree objects (should
  be precomposed form to be compatible with other systems and for
  consistency in general).

- The same for names stored in the index, which should be
  precomposed, that may need to be compared with the names read from
  readdir().

NFS mounted from Linux is fully transparent and does not suffer from
the above.

As Mac OS X treats precomposed and decomposed file names as equal,
we can

 - wrap readdir() on Mac OS X to return the precomposed form, and

 - normalize decomposed form given from the command line also to the
   precomposed form,

to ensure that all pathnames used in Git are always in the
precomposed form.  This behaviour can be requested by setting
"core.precomposedunicode" configuration variable to true.

The code in compat/precomposed_utf8.c implements basically 4 new
functions: precomposed_utf8_opendir(), precomposed_utf8_readdir(),
precomposed_utf8_closedir() and precompose_argv().  The first three
are to wrap opendir(3), readdir(3), and closedir(3) functions.

The argv[] conversion allows to use the TAB filename completion done
by the shell on command line.  It tolerates other tools which use
readdir() to feed decomposed file names into git.

When creating a new git repository with "git init" or "git clone",
"core.precomposedunicode" will be set "false".

The user needs to activate this feature manually.  She typically
sets core.precomposedunicode to "true" on HFS and VFAT, or file
systems mounted via SAMBA.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-07-08 22:03:46 -07:00

597 lines
16 KiB
C

/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.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 const char *git_link;
static void safe_create_dir(const char *dir, int share)
{
if (mkdir(dir, 0777) < 0) {
if (errno != EEXIST) {
perror(dir);
exit(1);
}
}
else if (share && adjust_shared_perm(dir))
die(_("Could not make %s writable by group"), dir);
}
static void copy_templates_1(char *path, int baselen,
char *template, int template_baselen,
DIR *dir)
{
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, 1);
while ((de = readdir(dir)) != NULL) {
struct stat st_git, st_template;
int namelen;
int exists = 0;
if (de->d_name[0] == '.')
continue;
namelen = strlen(de->d_name);
if ((PATH_MAX <= baselen + namelen) ||
(PATH_MAX <= template_baselen + namelen))
die(_("insanely long template name %s"), de->d_name);
memcpy(path + baselen, de->d_name, namelen+1);
memcpy(template + template_baselen, de->d_name, namelen+1);
if (lstat(path, &st_git)) {
if (errno != ENOENT)
die_errno(_("cannot stat '%s'"), path);
}
else
exists = 1;
if (lstat(template, &st_template))
die_errno(_("cannot stat template '%s'"), template);
if (S_ISDIR(st_template.st_mode)) {
DIR *subdir = opendir(template);
int baselen_sub = baselen + namelen;
int template_baselen_sub = template_baselen + namelen;
if (!subdir)
die_errno(_("cannot opendir '%s'"), template);
path[baselen_sub++] =
template[template_baselen_sub++] = '/';
path[baselen_sub] =
template[template_baselen_sub] = 0;
copy_templates_1(path, baselen_sub,
template, template_baselen_sub,
subdir);
closedir(subdir);
}
else if (exists)
continue;
else if (S_ISLNK(st_template.st_mode)) {
char lnk[256];
int len;
len = readlink(template, lnk, sizeof(lnk));
if (len < 0)
die_errno(_("cannot readlink '%s'"), template);
if (sizeof(lnk) <= len)
die(_("insanely long symlink %s"), template);
lnk[len] = 0;
if (symlink(lnk, path))
die_errno(_("cannot symlink '%s' '%s'"), lnk, path);
}
else if (S_ISREG(st_template.st_mode)) {
if (copy_file(path, template, st_template.st_mode))
die_errno(_("cannot copy '%s' to '%s'"), template,
path);
}
else
error(_("ignoring template %s"), template);
}
}
static void copy_templates(const char *template_dir)
{
char path[PATH_MAX];
char template_path[PATH_MAX];
int template_len;
DIR *dir;
const char *git_dir = get_git_dir();
int len = strlen(git_dir);
if (!template_dir)
template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
if (!template_dir)
template_dir = init_db_template_dir;
if (!template_dir)
template_dir = system_path(DEFAULT_GIT_TEMPLATE_DIR);
if (!template_dir[0])
return;
template_len = strlen(template_dir);
if (PATH_MAX <= (template_len+strlen("/config")))
die(_("insanely long template path %s"), template_dir);
strcpy(template_path, template_dir);
if (template_path[template_len-1] != '/') {
template_path[template_len++] = '/';
template_path[template_len] = 0;
}
dir = opendir(template_path);
if (!dir) {
warning(_("templates not found %s"), template_dir);
return;
}
/* Make sure that template is from the correct vintage */
strcpy(template_path + template_len, "config");
repository_format_version = 0;
git_config_from_file(check_repository_format_version,
template_path, NULL);
template_path[template_len] = 0;
if (repository_format_version &&
repository_format_version != GIT_REPO_VERSION) {
warning(_("not copying templates of "
"a wrong format version %d from '%s'"),
repository_format_version,
template_dir);
closedir(dir);
return;
}
memcpy(path, git_dir, len);
if (len && path[len - 1] != '/')
path[len++] = '/';
path[len] = 0;
copy_templates_1(path, len,
template_path, template_len,
dir);
closedir(dir);
}
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;
}
static int create_default_files(const char *template_path)
{
const char *git_dir = get_git_dir();
unsigned len = strlen(git_dir);
static char path[PATH_MAX];
struct stat st1;
char repo_version_string[10];
char junk[2];
int reinit;
int filemode;
if (len > sizeof(path)-50)
die(_("insane git directory %s"), git_dir);
memcpy(path, git_dir, len);
if (len && path[len-1] != '/')
path[len++] = '/';
/*
* Create .git/refs/{heads,tags}
*/
safe_create_dir(git_path("refs"), 1);
safe_create_dir(git_path("refs/heads"), 1);
safe_create_dir(git_path("refs/tags"), 1);
/* 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.
*/
copy_templates(template_path);
git_config(git_default_config, NULL);
is_bare_repository_cfg = init_is_bare_repository;
/* reading existing config may have overwrote it */
if (init_shared_repository != -1)
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 (shared_repository) {
adjust_shared_perm(get_git_dir());
adjust_shared_perm(git_path("refs"));
adjust_shared_perm(git_path("refs/heads"));
adjust_shared_perm(git_path("refs/tags"));
}
/*
* Create the default symlink from ".git/HEAD" to the "master"
* branch, if it does not exist yet.
*/
strcpy(path + len, "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 */
sprintf(repo_version_string, "%d", GIT_REPO_VERSION);
git_config_set("core.repositoryformatversion", repo_version_string);
path[len] = 0;
strcpy(path + len, "config");
/* Check filemode trustability */
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);
}
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 == -1)
git_config_set("core.logallrefupdates", "true");
if (prefixcmp(git_dir, work_tree) ||
strcmp(git_dir + strlen(work_tree), "/.git")) {
git_config_set("core.worktree", work_tree);
}
}
if (!reinit) {
/* Check if symlink is supported in the work tree */
path[len] = 0;
strcpy(path + len, "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[len] = 0;
strcpy(path + len, "CoNfIg");
if (!access(path, F_OK))
git_config_set("core.ignorecase", "true");
probe_utf8_pathname_composition(path, len);
}
return reinit;
}
static void create_object_directory(void)
{
const char *object_directory = get_object_directory();
int len = strlen(object_directory);
char *path = xmalloc(len + 40);
memcpy(path, object_directory, len);
safe_create_dir(object_directory, 1);
strcpy(path+len, "/pack");
safe_create_dir(path, 1);
strcpy(path+len, "/info");
safe_create_dir(path, 1);
free(path);
}
int set_git_dir_init(const char *git_dir, const char *real_git_dir,
int exist_ok)
{
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);
/*
* make sure symlinks are resolved because we'll be
* moving the target repo later on in separate_git_dir()
*/
git_link = xstrdup(real_path(git_dir));
}
else {
real_git_dir = real_path(git_dir);
git_link = NULL;
}
set_git_dir(real_path(real_git_dir));
return 0;
}
static void separate_git_dir(const char *git_dir)
{
struct stat st;
FILE *fp;
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);
}
fp = fopen(git_link, "w");
if (!fp)
die(_("Could not create git link %s"), git_link);
fprintf(fp, "gitdir: %s\n", git_dir);
fclose(fp);
}
int init_db(const char *template_dir, unsigned int flags)
{
int reinit;
const char *git_dir = get_git_dir();
if (git_link)
separate_git_dir(git_dir);
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);
create_object_directory();
if (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 (shared_repository < 0)
/* force to the mode value */
sprintf(buf, "0%o", -shared_repository);
else if (shared_repository == PERM_GROUP)
sprintf(buf, "%d", OLD_PERM_GROUP);
else if (shared_repository == PERM_EVERYBODY)
sprintf(buf, "%d", OLD_PERM_EVERYBODY);
else
die("oops");
git_config_set("core.sharedrepository", buf);
git_config_set("receive.denyNonFastforwards", "true");
}
if (!(flags & INIT_DB_QUIET)) {
int len = strlen(git_dir);
/*
* TRANSLATORS: The first '%s' is either "Reinitialized
* existing" or "Initialized empty", the second " shared" or
* "", and the last '%s%s' is the verbatim directory name.
*/
printf(_("%s%s Git repository in %s%s\n"),
reinit ? _("Reinitialized existing") : _("Initialized empty"),
shared_repository ? _(" shared") : "",
git_dir, len && git_dir[len-1] != '/' ? "/" : "");
}
return 0;
}
static int guess_repository_type(const char *git_dir)
{
char cwd[PATH_MAX];
const char *slash;
/*
* "GIT_DIR=. git init" is always bare.
* "GIT_DIR=`pwd` git init" too.
*/
if (!strcmp(".", git_dir))
return 1;
if (!getcwd(cwd, sizeof(cwd)))
die_errno(_("cannot tell cwd"));
if (!strcmp(git_dir, cwd))
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)
{
*((int *) opt->value) = (arg) ? git_config_perm("arg", arg) : PERM_GROUP;
return 0;
}
static const char *const init_db_usage[] = {
"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, "template-directory",
"directory from which templates will be used"),
OPT_SET_INT(0, "bare", &is_bare_repository_cfg,
"create a bare repository", 1),
{ OPTION_CALLBACK, 0, "shared", &init_shared_repository,
"permissions",
"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, "be quiet", INIT_DB_QUIET),
OPT_STRING(0, "separate-git-dir", &real_git_dir, "gitdir",
"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 = xstrdup(real_path(real_git_dir));
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 = shared_repository;
shared_repository = 0;
switch (safe_create_leading_directories_const(argv[0])) {
case -3:
errno = EEXIST;
/* fallthru */
case -1:
die_errno(_("cannot mkdir %s"), argv[0]);
break;
default:
break;
}
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) {
static char git_dir[PATH_MAX+1];
setenv(GIT_DIR_ENVIRONMENT,
getcwd(git_dir, sizeof(git_dir)), argc > 0);
}
if (init_shared_repository != -1)
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 = xstrdup(real_path(rel));
free(rel);
}
if (!git_work_tree_cfg) {
git_work_tree_cfg = xcalloc(PATH_MAX, 1);
if (!getcwd(git_work_tree_cfg, PATH_MAX))
die_errno (_("Cannot access current working directory"));
}
if (work_tree)
set_git_work_tree(real_path(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(real_path(work_tree));
}
set_git_dir_init(git_dir, real_git_dir, 1);
return init_db(template_dir, flags);
}