git/environment.c
Kirill Smelkov 15431ca651 setup: make sure git_dir path is in a permanent buffer, getenv(3) case
getenv(3) returns not-permanent buffer which may be changed by e.g.
putenv(3) call (*).

In practice I've noticed this when trying to do `git commit -m abc`
inside msysgit under wine, getting

    $ git commit -m abc
    fatal: could not open 'DIR=.git/COMMIT_EDITMSG': No such file or directory
                           ^^^^
    (notice introduced 'DIR=' artifact.)

The problem was showing itself only with -m option, and actually, as
debugging showed, originally

    git_dir = getenv("GIT_DIR")

returned pointer to

        "GIT_DIR=.git\0"
                 ^
               git_dir

, we stored it in git_dir, than, after processing -m git-commit option,
we did setenv("GIT_EDITOR", ":") which as (*) says changed environment
variables memory layout - something like this

       "...\0GIT_DIR=.git\0"
                 ^
               git_dir

and oops - we got wrong git_dir.

Avoid that by strdupping getenv("GIT_DIR") result like we did in 06f354
(setup: make sure git dir path is in a permanent buffer). Unfortunately
this also shows that other getenv usage inside git needs auditing...

(*) from man 3 getenv:

       The implementation of getenv() is not required to  be  reentrant.   The
       string  pointed  to  by  the return value of getenv() may be statically
       allocated, and can be  modified  by  a  subsequent  call  to  getenv(),
       putenv(3), setenv(3), or unsetenv(3).

Cc: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-12 16:03:27 -08:00

196 lines
5.3 KiB
C

/*
* We put all the git config variables in this same object
* file, so that programs can link against the config parser
* without having to link against all the rest of git.
*
* In particular, no need to bring in libz etc unless needed,
* even if you might want to know where the git directory etc
* are.
*/
#include "cache.h"
char git_default_email[MAX_GITNAME];
char git_default_name[MAX_GITNAME];
int user_ident_explicitly_given;
int trust_executable_bit = 1;
int trust_ctime = 1;
int has_symlinks = 1;
int ignore_case;
int assume_unchanged;
int prefer_symlink_refs;
int is_bare_repository_cfg = -1; /* unspecified */
int log_all_ref_updates = -1; /* unspecified */
int warn_ambiguous_refs = 1;
int repository_format_version;
const char *git_commit_encoding;
const char *git_log_output_encoding;
int shared_repository = PERM_UMASK;
const char *apply_default_whitespace;
const char *apply_default_ignorewhitespace;
int zlib_compression_level = Z_BEST_SPEED;
int core_compression_level;
int core_compression_seen;
int fsync_object_files;
size_t packed_git_window_size = DEFAULT_PACKED_GIT_WINDOW_SIZE;
size_t packed_git_limit = DEFAULT_PACKED_GIT_LIMIT;
size_t delta_base_cache_limit = 16 * 1024 * 1024;
const char *pager_program;
int pager_use_color = 1;
const char *editor_program;
const char *askpass_program;
const char *excludes_file;
enum auto_crlf auto_crlf = AUTO_CRLF_FALSE;
int read_replace_refs = 1;
enum eol eol = EOL_UNSET;
enum safe_crlf safe_crlf = SAFE_CRLF_WARN;
unsigned whitespace_rule_cfg = WS_DEFAULT_RULE;
enum branch_track git_branch_track = BRANCH_TRACK_REMOTE;
enum rebase_setup_type autorebase = AUTOREBASE_NEVER;
enum push_default_type push_default = PUSH_DEFAULT_MATCHING;
#ifndef OBJECT_CREATION_MODE
#define OBJECT_CREATION_MODE OBJECT_CREATION_USES_HARDLINKS
#endif
enum object_creation_mode object_creation_mode = OBJECT_CREATION_MODE;
char *notes_ref_name;
int grafts_replace_parents = 1;
int core_apply_sparse_checkout;
struct startup_info *startup_info;
/* Parallel index stat data preload? */
int core_preload_index = 0;
/* This is set by setup_git_dir_gently() and/or git_default_config() */
char *git_work_tree_cfg;
static char *work_tree;
static const char *git_dir;
static char *git_object_dir, *git_index_file, *git_graft_file;
/*
* Repository-local GIT_* environment variables
* Remember to update local_repo_env_size in cache.h when
* the size of the list changes
*/
const char * const local_repo_env[LOCAL_REPO_ENV_SIZE + 1] = {
ALTERNATE_DB_ENVIRONMENT,
CONFIG_ENVIRONMENT,
CONFIG_DATA_ENVIRONMENT,
DB_ENVIRONMENT,
GIT_DIR_ENVIRONMENT,
GIT_WORK_TREE_ENVIRONMENT,
GRAFT_ENVIRONMENT,
INDEX_ENVIRONMENT,
NO_REPLACE_OBJECTS_ENVIRONMENT,
NULL
};
static void setup_git_env(void)
{
git_dir = getenv(GIT_DIR_ENVIRONMENT);
git_dir = git_dir ? xstrdup(git_dir) : NULL;
if (!git_dir) {
git_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
git_dir = git_dir ? xstrdup(git_dir) : NULL;
}
if (!git_dir)
git_dir = DEFAULT_GIT_DIR_ENVIRONMENT;
git_object_dir = getenv(DB_ENVIRONMENT);
if (!git_object_dir) {
git_object_dir = xmalloc(strlen(git_dir) + 9);
sprintf(git_object_dir, "%s/objects", git_dir);
}
git_index_file = getenv(INDEX_ENVIRONMENT);
if (!git_index_file) {
git_index_file = xmalloc(strlen(git_dir) + 7);
sprintf(git_index_file, "%s/index", git_dir);
}
git_graft_file = getenv(GRAFT_ENVIRONMENT);
if (!git_graft_file)
git_graft_file = git_pathdup("info/grafts");
if (getenv(NO_REPLACE_OBJECTS_ENVIRONMENT))
read_replace_refs = 0;
}
int is_bare_repository(void)
{
/* if core.bare is not 'false', let's see if there is a work tree */
return is_bare_repository_cfg && !get_git_work_tree();
}
int have_git_dir(void)
{
return !!git_dir;
}
const char *get_git_dir(void)
{
if (!git_dir)
setup_git_env();
return git_dir;
}
static int git_work_tree_initialized;
/*
* Note. This works only before you used a work tree. This was added
* primarily to support git-clone to work in a new repository it just
* created, and is not meant to flip between different work trees.
*/
void set_git_work_tree(const char *new_work_tree)
{
if (is_bare_repository_cfg >= 0)
die("cannot set work tree after initialization");
git_work_tree_initialized = 1;
free(work_tree);
work_tree = xstrdup(make_absolute_path(new_work_tree));
is_bare_repository_cfg = 0;
}
const char *get_git_work_tree(void)
{
if (!git_work_tree_initialized) {
work_tree = getenv(GIT_WORK_TREE_ENVIRONMENT);
/* core.bare = true overrides implicit and config work tree */
if (!work_tree && is_bare_repository_cfg < 1) {
work_tree = git_work_tree_cfg;
/* make_absolute_path also normalizes the path */
if (work_tree && !is_absolute_path(work_tree))
work_tree = xstrdup(make_absolute_path(git_path("%s", work_tree)));
} else if (work_tree)
work_tree = xstrdup(make_absolute_path(work_tree));
git_work_tree_initialized = 1;
if (work_tree)
is_bare_repository_cfg = 0;
}
return work_tree;
}
char *get_object_directory(void)
{
if (!git_object_dir)
setup_git_env();
return git_object_dir;
}
char *get_index_file(void)
{
if (!git_index_file)
setup_git_env();
return git_index_file;
}
char *get_graft_file(void)
{
if (!git_graft_file)
setup_git_env();
return git_graft_file;
}
int set_git_dir(const char *path)
{
if (setenv(GIT_DIR_ENVIRONMENT, path, 1))
return error("Could not set GIT_DIR to '%s'", path);
setup_git_env();
return 0;
}