git/setup.c
Thomas Rast 0721c314a5 Use die_errno() instead of die() when checking syscalls
Lots of die() calls did not actually report the kind of error, which
can leave the user confused as to the real problem.  Use die_errno()
where we check a system/library call that sets errno on failure, or
one of the following that wrap such calls:

  Function              Passes on error from
  --------              --------------------
  odb_pack_keep         open
  read_ancestry         fopen
  read_in_full          xread
  strbuf_read           xread
  strbuf_read_file      open or strbuf_read_file
  strbuf_readlink       readlink
  write_in_full         xwrite

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-06-27 11:14:53 -07:00

505 lines
13 KiB
C

#include "cache.h"
#include "dir.h"
static int inside_git_dir = -1;
static int inside_work_tree = -1;
const char *prefix_path(const char *prefix, int len, const char *path)
{
const char *orig = path;
char *sanitized = xmalloc(len + strlen(path) + 1);
if (is_absolute_path(orig))
strcpy(sanitized, path);
else {
if (len)
memcpy(sanitized, prefix, len);
strcpy(sanitized + len, path);
}
if (normalize_path_copy(sanitized, sanitized))
goto error_out;
if (is_absolute_path(orig)) {
const char *work_tree = get_git_work_tree();
size_t len = strlen(work_tree);
size_t total = strlen(sanitized) + 1;
if (strncmp(sanitized, work_tree, len) ||
(sanitized[len] != '\0' && sanitized[len] != '/')) {
error_out:
die("'%s' is outside repository", orig);
}
if (sanitized[len] == '/')
len++;
memmove(sanitized, sanitized + len, total - len);
}
return sanitized;
}
/*
* Unlike prefix_path, this should be used if the named file does
* not have to interact with index entry; i.e. name of a random file
* on the filesystem.
*/
const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
{
static char path[PATH_MAX];
#ifndef __MINGW32__
if (!pfx || !*pfx || is_absolute_path(arg))
return arg;
memcpy(path, pfx, pfx_len);
strcpy(path + pfx_len, arg);
#else
char *p;
/* don't add prefix to absolute paths, but still replace '\' by '/' */
if (is_absolute_path(arg))
pfx_len = 0;
else
memcpy(path, pfx, pfx_len);
strcpy(path + pfx_len, arg);
for (p = path + pfx_len; *p; p++)
if (*p == '\\')
*p = '/';
#endif
return path;
}
/*
* Verify a filename that we got as an argument for a pathspec
* entry. Note that a filename that begins with "-" never verifies
* as true, because even if such a filename were to exist, we want
* it to be preceded by the "--" marker (or we want the user to
* use a format like "./-filename")
*/
void verify_filename(const char *prefix, const char *arg)
{
const char *name;
struct stat st;
if (*arg == '-')
die("bad flag '%s' used after filename", arg);
name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
if (!lstat(name, &st))
return;
if (errno == ENOENT)
die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
"Use '--' to separate paths from revisions", arg);
die_errno("failed to stat '%s'", arg);
}
/*
* Opposite of the above: the command line did not have -- marker
* and we parsed the arg as a refname. It should not be interpretable
* as a filename.
*/
void verify_non_filename(const char *prefix, const char *arg)
{
const char *name;
struct stat st;
if (!is_inside_work_tree() || is_inside_git_dir())
return;
if (*arg == '-')
return; /* flag */
name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
if (!lstat(name, &st))
die("ambiguous argument '%s': both revision and filename\n"
"Use '--' to separate filenames from revisions", arg);
if (errno != ENOENT && errno != ENOTDIR)
die_errno("failed to stat '%s'", arg);
}
const char **get_pathspec(const char *prefix, const char **pathspec)
{
const char *entry = *pathspec;
const char **src, **dst;
int prefixlen;
if (!prefix && !entry)
return NULL;
if (!entry) {
static const char *spec[2];
spec[0] = prefix;
spec[1] = NULL;
return spec;
}
/* Otherwise we have to re-write the entries.. */
src = pathspec;
dst = pathspec;
prefixlen = prefix ? strlen(prefix) : 0;
while (*src) {
const char *p = prefix_path(prefix, prefixlen, *src);
*(dst++) = p;
src++;
}
*dst = NULL;
if (!*pathspec)
return NULL;
return pathspec;
}
/*
* Test if it looks like we're at a git directory.
* We want to see:
*
* - either an objects/ directory _or_ the proper
* GIT_OBJECT_DIRECTORY environment variable
* - a refs/ directory
* - either a HEAD symlink or a HEAD file that is formatted as
* a proper "ref:", or a regular file HEAD that has a properly
* formatted sha1 object name.
*/
static int is_git_directory(const char *suspect)
{
char path[PATH_MAX];
size_t len = strlen(suspect);
strcpy(path, suspect);
if (getenv(DB_ENVIRONMENT)) {
if (access(getenv(DB_ENVIRONMENT), X_OK))
return 0;
}
else {
strcpy(path + len, "/objects");
if (access(path, X_OK))
return 0;
}
strcpy(path + len, "/refs");
if (access(path, X_OK))
return 0;
strcpy(path + len, "/HEAD");
if (validate_headref(path))
return 0;
return 1;
}
int is_inside_git_dir(void)
{
if (inside_git_dir < 0)
inside_git_dir = is_inside_dir(get_git_dir());
return inside_git_dir;
}
int is_inside_work_tree(void)
{
if (inside_work_tree < 0)
inside_work_tree = is_inside_dir(get_git_work_tree());
return inside_work_tree;
}
/*
* set_work_tree() is only ever called if you set GIT_DIR explicitely.
* The old behaviour (which we retain here) is to set the work tree root
* to the cwd, unless overridden by the config, the command line, or
* GIT_WORK_TREE.
*/
static const char *set_work_tree(const char *dir)
{
char buffer[PATH_MAX + 1];
if (!getcwd(buffer, sizeof(buffer)))
die ("Could not get the current working directory");
git_work_tree_cfg = xstrdup(buffer);
inside_work_tree = 1;
return NULL;
}
void setup_work_tree(void)
{
const char *work_tree, *git_dir;
static int initialized = 0;
if (initialized)
return;
work_tree = get_git_work_tree();
git_dir = get_git_dir();
if (!is_absolute_path(git_dir))
git_dir = make_absolute_path(git_dir);
if (!work_tree || chdir(work_tree))
die("This operation must be run in a work tree");
set_git_dir(make_relative_path(git_dir, work_tree));
initialized = 1;
}
static int check_repository_format_gently(int *nongit_ok)
{
git_config(check_repository_format_version, NULL);
if (GIT_REPO_VERSION < repository_format_version) {
if (!nongit_ok)
die ("Expected git repo version <= %d, found %d",
GIT_REPO_VERSION, repository_format_version);
warning("Expected git repo version <= %d, found %d",
GIT_REPO_VERSION, repository_format_version);
warning("Please upgrade Git");
*nongit_ok = -1;
return -1;
}
return 0;
}
/*
* Try to read the location of the git directory from the .git file,
* return path to git directory if found.
*/
const char *read_gitfile_gently(const char *path)
{
char *buf;
struct stat st;
int fd;
size_t len;
if (stat(path, &st))
return NULL;
if (!S_ISREG(st.st_mode))
return NULL;
fd = open(path, O_RDONLY);
if (fd < 0)
die_errno("Error opening '%s'", path);
buf = xmalloc(st.st_size + 1);
len = read_in_full(fd, buf, st.st_size);
close(fd);
if (len != st.st_size)
die("Error reading %s", path);
buf[len] = '\0';
if (prefixcmp(buf, "gitdir: "))
die("Invalid gitfile format: %s", path);
while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
len--;
if (len < 9)
die("No path in gitfile: %s", path);
buf[len] = '\0';
if (!is_git_directory(buf + 8))
die("Not a git repository: %s", buf + 8);
path = make_absolute_path(buf + 8);
free(buf);
return path;
}
/*
* We cannot decide in this function whether we are in the work tree or
* not, since the config can only be read _after_ this function was called.
*/
const char *setup_git_directory_gently(int *nongit_ok)
{
const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
static char cwd[PATH_MAX+1];
const char *gitdirenv;
const char *gitfile_dir;
int len, offset, ceil_offset;
/*
* Let's assume that we are in a git repository.
* If it turns out later that we are somewhere else, the value will be
* updated accordingly.
*/
if (nongit_ok)
*nongit_ok = 0;
/*
* If GIT_DIR is set explicitly, we're not going
* to do any discovery, but we still do repository
* validation.
*/
gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
if (gitdirenv) {
if (PATH_MAX - 40 < strlen(gitdirenv))
die("'$%s' too big", GIT_DIR_ENVIRONMENT);
if (is_git_directory(gitdirenv)) {
static char buffer[1024 + 1];
const char *retval;
if (!work_tree_env) {
retval = set_work_tree(gitdirenv);
/* config may override worktree */
if (check_repository_format_gently(nongit_ok))
return NULL;
return retval;
}
if (check_repository_format_gently(nongit_ok))
return NULL;
retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
get_git_work_tree());
if (!retval || !*retval)
return NULL;
set_git_dir(make_absolute_path(gitdirenv));
if (chdir(work_tree_env) < 0)
die_errno ("Could not chdir to '%s'", work_tree_env);
strcat(buffer, "/");
return retval;
}
if (nongit_ok) {
*nongit_ok = 1;
return NULL;
}
die("Not a git repository: '%s'", gitdirenv);
}
if (!getcwd(cwd, sizeof(cwd)-1))
die_errno("Unable to read current working directory");
ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
ceil_offset = 1;
/*
* Test in the following order (relative to the cwd):
* - .git (file containing "gitdir: <path>")
* - .git/
* - ./ (bare)
* - ../.git
* - ../.git/
* - ../ (bare)
* - ../../.git/
* etc.
*/
offset = len = strlen(cwd);
for (;;) {
gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
if (gitfile_dir) {
if (set_git_dir(gitfile_dir))
die("Repository setup failed");
break;
}
if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
break;
if (is_git_directory(".")) {
inside_git_dir = 1;
if (!work_tree_env)
inside_work_tree = 0;
if (offset != len) {
cwd[offset] = '\0';
setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
} else
setenv(GIT_DIR_ENVIRONMENT, ".", 1);
check_repository_format_gently(nongit_ok);
return NULL;
}
while (--offset > ceil_offset && cwd[offset] != '/');
if (offset <= ceil_offset) {
if (nongit_ok) {
if (chdir(cwd))
die_errno("Cannot come back to cwd");
*nongit_ok = 1;
return NULL;
}
die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
}
if (chdir(".."))
die_errno("Cannot change to '%s/..'", cwd);
}
inside_git_dir = 0;
if (!work_tree_env)
inside_work_tree = 1;
git_work_tree_cfg = xstrndup(cwd, offset);
if (check_repository_format_gently(nongit_ok))
return NULL;
if (offset == len)
return NULL;
/* Make "offset" point to past the '/', and add a '/' at the end */
offset++;
cwd[len++] = '/';
cwd[len] = 0;
return cwd + offset;
}
int git_config_perm(const char *var, const char *value)
{
int i;
char *endptr;
if (value == NULL)
return PERM_GROUP;
if (!strcmp(value, "umask"))
return PERM_UMASK;
if (!strcmp(value, "group"))
return PERM_GROUP;
if (!strcmp(value, "all") ||
!strcmp(value, "world") ||
!strcmp(value, "everybody"))
return PERM_EVERYBODY;
/* Parse octal numbers */
i = strtol(value, &endptr, 8);
/* If not an octal number, maybe true/false? */
if (*endptr != 0)
return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
/*
* Treat values 0, 1 and 2 as compatibility cases, otherwise it is
* a chmod value to restrict to.
*/
switch (i) {
case PERM_UMASK: /* 0 */
return PERM_UMASK;
case OLD_PERM_GROUP: /* 1 */
return PERM_GROUP;
case OLD_PERM_EVERYBODY: /* 2 */
return PERM_EVERYBODY;
}
/* A filemode value was given: 0xxx */
if ((i & 0600) != 0600)
die("Problem with core.sharedRepository filemode value "
"(0%.3o).\nThe owner of files must always have "
"read and write permissions.", i);
/*
* Mask filemode value. Others can not get write permission.
* x flags for directories are handled separately.
*/
return -(i & 0666);
}
int check_repository_format_version(const char *var, const char *value, void *cb)
{
if (strcmp(var, "core.repositoryformatversion") == 0)
repository_format_version = git_config_int(var, value);
else if (strcmp(var, "core.sharedrepository") == 0)
shared_repository = git_config_perm(var, value);
else if (strcmp(var, "core.bare") == 0) {
is_bare_repository_cfg = git_config_bool(var, value);
if (is_bare_repository_cfg == 1)
inside_work_tree = -1;
} else if (strcmp(var, "core.worktree") == 0) {
if (!value)
return config_error_nonbool(var);
free(git_work_tree_cfg);
git_work_tree_cfg = xstrdup(value);
inside_work_tree = -1;
}
return 0;
}
int check_repository_format(void)
{
return check_repository_format_gently(NULL);
}
const char *setup_git_directory(void)
{
const char *retval = setup_git_directory_gently(NULL);
/* If the work tree is not the default one, recompute prefix */
if (inside_work_tree < 0) {
static char buffer[PATH_MAX + 1];
char *rel;
if (retval && chdir(retval))
die_errno ("Could not jump back into original cwd");
rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
if (rel && *rel && chdir(get_git_work_tree()))
die_errno ("Could not jump to working directory");
return rel && *rel ? strcat(rel, "/") : NULL;
}
return retval;
}