diff options
Diffstat (limited to 'setup.c')
| -rw-r--r-- | setup.c | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/setup.c b/setup.c new file mode 100644 index 0000000000..41e298b8f5 --- /dev/null +++ b/setup.c @@ -0,0 +1,480 @@ +#include "cache.h" +#include "dir.h" + +static int inside_git_dir = -1; +static int inside_work_tree = -1; + +static int sanitary_path_copy(char *dst, const char *src) +{ + char *dst0 = dst; + + if (*src == '/') { + *dst++ = '/'; + while (*src == '/') + src++; + } + + for (;;) { + char c = *src; + + /* + * A path component that begins with . could be + * special: + * (1) "." and ends -- ignore and terminate. + * (2) "./" -- ignore them, eat slash and continue. + * (3) ".." and ends -- strip one and terminate. + * (4) "../" -- strip one, eat slash and continue. + */ + if (c == '.') { + switch (src[1]) { + case '\0': + /* (1) */ + src++; + break; + case '/': + /* (2) */ + src += 2; + while (*src == '/') + src++; + continue; + case '.': + switch (src[2]) { + case '\0': + /* (3) */ + src += 2; + goto up_one; + case '/': + /* (4) */ + src += 3; + while (*src == '/') + src++; + goto up_one; + } + } + } + + /* copy up to the next '/', and eat all '/' */ + while ((c = *src++) != '\0' && c != '/') + *dst++ = c; + if (c == '/') { + *dst++ = c; + while (c == '/') + c = *src++; + src--; + } else if (!c) + break; + continue; + + up_one: + /* + * dst0..dst is prefix portion, and dst[-1] is '/'; + * go up one level. + */ + dst -= 2; /* go past trailing '/' if any */ + if (dst < dst0) + return -1; + while (1) { + if (dst <= dst0) + break; + c = *dst--; + if (c == '/') { + dst += 2; + break; + } + } + } + *dst = '\0'; + return 0; +} + +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 (sanitary_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: + error("'%s' is outside repository", orig); + free(sanitized); + return NULL; + } + 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]; + if (!pfx || !*pfx || is_absolute_path(arg)) + return arg; + memcpy(path, pfx, pfx_len); + strcpy(path + pfx_len, arg); + 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("'%s': %s", arg, strerror(errno)); +} + +/* + * 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("'%s': %s", arg, strerror(errno)); +} + +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); + if (p) + *(dst++) = p; + else + exit(128); /* error message already given */ + 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)) + set_git_dir(make_absolute_path(git_dir)); + if (!work_tree || chdir(work_tree)) + die("This operation must be run in a work tree"); + initialized = 1; +} + +static int check_repository_format_gently(int *nongit_ok) +{ + git_config(check_repository_format_version); + 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; +} + +/* + * 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); + static char cwd[PATH_MAX+1]; + const char *gitdirenv; + int len, offset; + + /* + * 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 ("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("Unable to read current working directory"); + + /* + * Test in the following order (relative to the cwd): + * - .git/ + * - ./ (bare) + * - ../.git/ + * - ../ (bare) + * - ../../.git/ + * etc. + */ + offset = len = strlen(cwd); + for (;;) { + 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; + setenv(GIT_DIR_ENVIRONMENT, ".", 1); + check_repository_format_gently(nongit_ok); + return NULL; + } + chdir(".."); + do { + if (!offset) { + if (nongit_ok) { + if (chdir(cwd)) + die("Cannot come back to cwd"); + *nongit_ok = 1; + return NULL; + } + die("Not a git repository"); + } + } while (cwd[--offset] != '/'); + } + + 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) +{ + if (value) { + int i; + 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; + i = atoi(value); + if (i > 1) + return i; + } + return git_config_bool(var, value); +} + +int check_repository_format_version(const char *var, const char *value) +{ + 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 ("Could not jump back into original cwd"); + rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree()); + return rel && *rel ? strcat(rel, "/") : NULL; + } + + return retval; +} |