diff options
Diffstat (limited to 'setup.c')
| -rw-r--r-- | setup.c | 789 |
1 files changed, 789 insertions, 0 deletions
diff --git a/setup.c b/setup.c new file mode 100644 index 000000000..7a3618fab --- /dev/null +++ b/setup.c @@ -0,0 +1,789 @@ +#include "cache.h" +#include "dir.h" + +static int inside_git_dir = -1; +static int inside_work_tree = -1; + +char *prefix_path(const char *prefix, int len, const char *path) +{ + const char *orig = path; + char *sanitized; + if (is_absolute_path(orig)) { + const char *temp = real_path(path); + sanitized = xmalloc(len + strlen(temp) + 1); + strcpy(sanitized, temp); + } else { + sanitized = xmalloc(len + strlen(path) + 1); + if (len) + memcpy(sanitized, prefix, len); + strcpy(sanitized + len, path); + } + if (normalize_path_copy(sanitized, sanitized)) + goto error_out; + if (is_absolute_path(orig)) { + size_t root_len, len, total; + const char *work_tree = get_git_work_tree(); + if (!work_tree) + goto error_out; + len = strlen(work_tree); + root_len = offset_1st_component(work_tree); + total = strlen(sanitized) + 1; + if (strncmp(sanitized, work_tree, len) || + (len > root_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; +} + +int check_filename(const char *prefix, const char *arg) +{ + const char *name; + struct stat st; + + name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg; + if (!lstat(name, &st)) + return 1; /* file exists */ + if (errno == ENOENT || errno == ENOTDIR) + return 0; /* file does not exist */ + die_errno("failed to stat '%s'", arg); +} + +static void NORETURN die_verify_filename(const char *prefix, const char *arg) +{ + unsigned char sha1[20]; + unsigned mode; + + /* + * Saying "'(icase)foo' does not exist in the index" when the + * user gave us ":(icase)foo" is just stupid. A magic pathspec + * begins with a colon and is followed by a non-alnum; do not + * let get_sha1_with_mode_1(only_to_die=1) to even trigger. + */ + if (!(arg[0] == ':' && !isalnum(arg[1]))) + /* try a detailed diagnostic ... */ + get_sha1_with_mode_1(arg, sha1, &mode, 1, prefix); + + /* ... or fall back the most general message. */ + die("ambiguous argument '%s': unknown revision or path not in the working tree.\n" + "Use '--' to separate paths from revisions", arg); + +} + +/* + * 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) +{ + if (*arg == '-') + die("bad flag '%s' used after filename", arg); + if (check_filename(prefix, arg)) + return; + die_verify_filename(prefix, 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) +{ + if (!is_inside_work_tree() || is_inside_git_dir()) + return; + if (*arg == '-') + return; /* flag */ + if (!check_filename(prefix, arg)) + return; + die("ambiguous argument '%s': both revision and filename\n" + "Use '--' to separate filenames from revisions", arg); +} + +/* + * Magic pathspec + * + * NEEDSWORK: These need to be moved to dir.h or even to a new + * pathspec.h when we restructure get_pathspec() users to use the + * "struct pathspec" interface. + * + * Possible future magic semantics include stuff like: + * + * { PATHSPEC_NOGLOB, '!', "noglob" }, + * { PATHSPEC_ICASE, '\0', "icase" }, + * { PATHSPEC_RECURSIVE, '*', "recursive" }, + * { PATHSPEC_REGEXP, '\0', "regexp" }, + * + */ +#define PATHSPEC_FROMTOP (1<<0) + +static struct pathspec_magic { + unsigned bit; + char mnemonic; /* this cannot be ':'! */ + const char *name; +} pathspec_magic[] = { + { PATHSPEC_FROMTOP, '/', "top" }, +}; + +/* + * Take an element of a pathspec and check for magic signatures. + * Append the result to the prefix. + * + * For now, we only parse the syntax and throw out anything other than + * "top" magic. + * + * NEEDSWORK: This needs to be rewritten when we start migrating + * get_pathspec() users to use the "struct pathspec" interface. For + * example, a pathspec element may be marked as case-insensitive, but + * the prefix part must always match literally, and a single stupid + * string cannot express such a case. + */ +static const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt) +{ + unsigned magic = 0; + const char *copyfrom = elt; + int i; + + if (elt[0] != ':') { + ; /* nothing to do */ + } else if (elt[1] == '(') { + /* longhand */ + const char *nextat; + for (copyfrom = elt + 2; + *copyfrom && *copyfrom != ')'; + copyfrom = nextat) { + size_t len = strcspn(copyfrom, ",)"); + if (copyfrom[len] == ')') + nextat = copyfrom + len; + else + nextat = copyfrom + len + 1; + if (!len) + continue; + for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) + if (strlen(pathspec_magic[i].name) == len && + !strncmp(pathspec_magic[i].name, copyfrom, len)) { + magic |= pathspec_magic[i].bit; + break; + } + if (ARRAY_SIZE(pathspec_magic) <= i) + die("Invalid pathspec magic '%.*s' in '%s'", + (int) len, copyfrom, elt); + } + if (*copyfrom == ')') + copyfrom++; + } else { + /* shorthand */ + for (copyfrom = elt + 1; + *copyfrom && *copyfrom != ':'; + copyfrom++) { + char ch = *copyfrom; + + if (!is_pathspec_magic(ch)) + break; + for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) + if (pathspec_magic[i].mnemonic == ch) { + magic |= pathspec_magic[i].bit; + break; + } + if (ARRAY_SIZE(pathspec_magic) <= i) + die("Unimplemented pathspec magic '%c' in '%s'", + ch, elt); + } + if (*copyfrom == ':') + copyfrom++; + } + + if (magic & PATHSPEC_FROMTOP) + return xstrdup(copyfrom); + else + return prefix_path(prefix, prefixlen, copyfrom); +} + +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) { + *(dst++) = prefix_pathspec(prefix, prefixlen, *src); + 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. + */ +int is_git_directory(const char *suspect) +{ + char path[PATH_MAX]; + size_t len = strlen(suspect); + + if (PATH_MAX <= len + strlen("/objects")) + die("Too long path: %.*s", 60, 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; +} + +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 = real_path(get_git_dir()); + if (!work_tree || chdir(work_tree)) + die("This operation must be run in a work tree"); + + /* + * Make sure subsequent git processes find correct worktree + * if $GIT_WORK_TREE is set relative + */ + if (getenv(GIT_WORK_TREE_ENVIRONMENT)) + setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1); + + set_git_dir(relative_path(git_dir, work_tree)); + initialized = 1; +} + +static int check_repository_format_gently(const char *gitdir, int *nongit_ok) +{ + char repo_config[PATH_MAX+1]; + + /* + * git_config() can't be used here because it calls git_pathdup() + * to get $GIT_CONFIG/config. That call will make setup_git_env() + * set git_dir to ".git". + * + * We are in gitdir setup, no git dir has been found useable yet. + * Use a gentler version of git_config() to check if this repo + * is a good one. + */ + snprintf(repo_config, PATH_MAX, "%s/config", gitdir); + git_config_early(check_repository_format_version, NULL, repo_config); + 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(const char *path) +{ + char *buf; + char *dir; + const char *slash; + struct stat st; + int fd; + ssize_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'; + dir = buf + 8; + + if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) { + size_t pathlen = slash+1 - path; + size_t dirlen = pathlen + len - 8; + dir = xmalloc(dirlen + 1); + strncpy(dir, path, pathlen); + strncpy(dir + pathlen, buf + 8, len - 8); + dir[dirlen] = '\0'; + free(buf); + buf = dir; + } + + if (!is_git_directory(dir)) + die("Not a git repository: %s", dir); + path = real_path(dir); + + free(buf); + return path; +} + +static const char *setup_explicit_git_dir(const char *gitdirenv, + char *cwd, int len, + int *nongit_ok) +{ + const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT); + const char *worktree; + char *gitfile; + int offset; + + if (PATH_MAX - 40 < strlen(gitdirenv)) + die("'$%s' too big", GIT_DIR_ENVIRONMENT); + + gitfile = (char*)read_gitfile(gitdirenv); + if (gitfile) { + gitfile = xstrdup(gitfile); + gitdirenv = gitfile; + } + + if (!is_git_directory(gitdirenv)) { + if (nongit_ok) { + *nongit_ok = 1; + free(gitfile); + return NULL; + } + die("Not a git repository: '%s'", gitdirenv); + } + + if (check_repository_format_gently(gitdirenv, nongit_ok)) { + free(gitfile); + return NULL; + } + + /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */ + if (work_tree_env) + set_git_work_tree(work_tree_env); + else if (is_bare_repository_cfg > 0) { + if (git_work_tree_cfg) /* #22.2, #30 */ + die("core.bare and core.worktree do not make sense"); + + /* #18, #26 */ + set_git_dir(gitdirenv); + free(gitfile); + return NULL; + } + else if (git_work_tree_cfg) { /* #6, #14 */ + if (is_absolute_path(git_work_tree_cfg)) + set_git_work_tree(git_work_tree_cfg); + else { + char core_worktree[PATH_MAX]; + if (chdir(gitdirenv)) + die_errno("Could not chdir to '%s'", gitdirenv); + if (chdir(git_work_tree_cfg)) + die_errno("Could not chdir to '%s'", git_work_tree_cfg); + if (!getcwd(core_worktree, PATH_MAX)) + die_errno("Could not get directory '%s'", git_work_tree_cfg); + if (chdir(cwd)) + die_errno("Could not come back to cwd"); + set_git_work_tree(core_worktree); + } + } + else /* #2, #10 */ + set_git_work_tree("."); + + /* set_git_work_tree() must have been called by now */ + worktree = get_git_work_tree(); + + /* both get_git_work_tree() and cwd are already normalized */ + if (!strcmp(cwd, worktree)) { /* cwd == worktree */ + set_git_dir(gitdirenv); + free(gitfile); + return NULL; + } + + offset = dir_inside_of(cwd, worktree); + if (offset >= 0) { /* cwd inside worktree? */ + set_git_dir(real_path(gitdirenv)); + if (chdir(worktree)) + die_errno("Could not chdir to '%s'", worktree); + cwd[len++] = '/'; + cwd[len] = '\0'; + free(gitfile); + return cwd + offset; + } + + /* cwd outside worktree */ + set_git_dir(gitdirenv); + free(gitfile); + return NULL; +} + +static const char *setup_discovered_git_dir(const char *gitdir, + char *cwd, int offset, int len, + int *nongit_ok) +{ + if (check_repository_format_gently(gitdir, nongit_ok)) + return NULL; + + /* --work-tree is set without --git-dir; use discovered one */ + if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) { + if (offset != len && !is_absolute_path(gitdir)) + gitdir = xstrdup(real_path(gitdir)); + if (chdir(cwd)) + die_errno("Could not come back to cwd"); + return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok); + } + + /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */ + if (is_bare_repository_cfg > 0) { + set_git_dir(offset == len ? gitdir : real_path(gitdir)); + if (chdir(cwd)) + die_errno("Could not come back to cwd"); + return NULL; + } + + /* #0, #1, #5, #8, #9, #12, #13 */ + set_git_work_tree("."); + if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT)) + set_git_dir(gitdir); + inside_git_dir = 0; + inside_work_tree = 1; + 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; +} + +/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */ +static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok) +{ + int root_len; + + if (check_repository_format_gently(".", nongit_ok)) + return NULL; + + /* --work-tree is set without --git-dir; use discovered one */ + if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) { + const char *gitdir; + + gitdir = offset == len ? "." : xmemdupz(cwd, offset); + if (chdir(cwd)) + die_errno("Could not come back to cwd"); + return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok); + } + + inside_git_dir = 1; + inside_work_tree = 0; + if (offset != len) { + if (chdir(cwd)) + die_errno("Cannot come back to cwd"); + root_len = offset_1st_component(cwd); + cwd[offset > root_len ? offset : root_len] = '\0'; + set_git_dir(cwd); + } + else + set_git_dir("."); + return NULL; +} + +static const char *setup_nongit(const char *cwd, int *nongit_ok) +{ + if (!nongit_ok) + die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT); + if (chdir(cwd)) + die_errno("Cannot come back to cwd"); + *nongit_ok = 1; + return NULL; +} + +static dev_t get_device_or_die(const char *path, const char *prefix) +{ + struct stat buf; + if (stat(path, &buf)) + die_errno("failed to stat '%s%s%s'", + prefix ? prefix : "", + prefix ? "/" : "", path); + return buf.st_dev; +} + +/* + * 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. + */ +static const char *setup_git_directory_gently_1(int *nongit_ok) +{ + const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT); + static char cwd[PATH_MAX+1]; + const char *gitdirenv, *ret; + char *gitfile; + int len, offset, ceil_offset; + dev_t current_device = 0; + int one_filesystem = 1; + + /* + * 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 (!getcwd(cwd, sizeof(cwd)-1)) + die_errno("Unable to read current working directory"); + offset = len = strlen(cwd); + + /* + * 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) + return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok); + + 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. + */ + one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0); + if (one_filesystem) + current_device = get_device_or_die(".", NULL); + for (;;) { + gitfile = (char*)read_gitfile(DEFAULT_GIT_DIR_ENVIRONMENT); + if (gitfile) + gitdirenv = gitfile = xstrdup(gitfile); + else { + if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT)) + gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT; + } + + if (gitdirenv) { + ret = setup_discovered_git_dir(gitdirenv, + cwd, offset, len, + nongit_ok); + free(gitfile); + return ret; + } + free(gitfile); + + if (is_git_directory(".")) + return setup_bare_git_dir(cwd, offset, len, nongit_ok); + + while (--offset > ceil_offset && cwd[offset] != '/'); + if (offset <= ceil_offset) + return setup_nongit(cwd, nongit_ok); + if (one_filesystem) { + dev_t parent_device = get_device_or_die("..", cwd); + if (parent_device != current_device) { + if (nongit_ok) { + if (chdir(cwd)) + die_errno("Cannot come back to cwd"); + *nongit_ok = 1; + return NULL; + } + cwd[offset] = '\0'; + die("Not a git repository (or any parent up to mount parent %s)\n" + "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd); + } + } + if (chdir("..")) { + cwd[offset] = '\0'; + die_errno("Cannot change to '%s/..'", cwd); + } + } +} + +const char *setup_git_directory_gently(int *nongit_ok) +{ + const char *prefix; + + prefix = setup_git_directory_gently_1(nongit_ok); + if (prefix) + setenv("GIT_PREFIX", prefix, 1); + else + setenv("GIT_PREFIX", "", 1); + + if (startup_info) { + startup_info->have_repository = !nongit_ok || !*nongit_ok; + startup_info->prefix = prefix; + } + return prefix; +} + +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(get_git_dir(), NULL); +} + +/* + * Returns the "prefix", a path to the current working directory + * relative to the work tree root, or NULL, if the current working + * directory is not a strict subdirectory of the work tree root. The + * prefix always ends with a '/' character. + */ +const char *setup_git_directory(void) +{ + return setup_git_directory_gently(NULL); +} + +const char *resolve_gitdir(const char *suspect) +{ + if (is_git_directory(suspect)) + return suspect; + return read_gitfile(suspect); +} |