|  | /* | 
|  | * I'm tired of doing "vsnprintf()" etc just to open a | 
|  | * file, so here's a "return static buffer with printf" | 
|  | * interface for paths. | 
|  | * | 
|  | * It's obviously not thread-safe. Sue me. But it's quite | 
|  | * useful for doing things like | 
|  | * | 
|  | *   f = open(mkpath("%s/%s.git", base, name), O_RDONLY); | 
|  | * | 
|  | * which is what it's designed for. | 
|  | */ | 
|  | #include "cache.h" | 
|  |  | 
|  | static char bad_path[] = "/bad-path/"; | 
|  |  | 
|  | static char *get_pathname(void) | 
|  | { | 
|  | static char pathname_array[4][PATH_MAX]; | 
|  | static int index; | 
|  | return pathname_array[3 & ++index]; | 
|  | } | 
|  |  | 
|  | static char *cleanup_path(char *path) | 
|  | { | 
|  | /* Clean it up */ | 
|  | if (!memcmp(path, "./", 2)) { | 
|  | path += 2; | 
|  | while (*path == '/') | 
|  | path++; | 
|  | } | 
|  | return path; | 
|  | } | 
|  |  | 
|  | char *mkpath(const char *fmt, ...) | 
|  | { | 
|  | va_list args; | 
|  | unsigned len; | 
|  | char *pathname = get_pathname(); | 
|  |  | 
|  | va_start(args, fmt); | 
|  | len = vsnprintf(pathname, PATH_MAX, fmt, args); | 
|  | va_end(args); | 
|  | if (len >= PATH_MAX) | 
|  | return bad_path; | 
|  | return cleanup_path(pathname); | 
|  | } | 
|  |  | 
|  | char *git_path(const char *fmt, ...) | 
|  | { | 
|  | const char *git_dir = get_git_dir(); | 
|  | char *pathname = get_pathname(); | 
|  | va_list args; | 
|  | unsigned len; | 
|  |  | 
|  | len = strlen(git_dir); | 
|  | if (len > PATH_MAX-100) | 
|  | return bad_path; | 
|  | memcpy(pathname, git_dir, len); | 
|  | if (len && git_dir[len-1] != '/') | 
|  | pathname[len++] = '/'; | 
|  | va_start(args, fmt); | 
|  | len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args); | 
|  | va_end(args); | 
|  | if (len >= PATH_MAX) | 
|  | return bad_path; | 
|  | return cleanup_path(pathname); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* git_mkstemp() - create tmp file honoring TMPDIR variable */ | 
|  | int git_mkstemp(char *path, size_t len, const char *template) | 
|  | { | 
|  | const char *tmp; | 
|  | size_t n; | 
|  |  | 
|  | tmp = getenv("TMPDIR"); | 
|  | if (!tmp) | 
|  | tmp = "/tmp"; | 
|  | n = snprintf(path, len, "%s/%s", tmp, template); | 
|  | if (len <= n) { | 
|  | errno = ENAMETOOLONG; | 
|  | return -1; | 
|  | } | 
|  | return mkstemp(path); | 
|  | } | 
|  |  | 
|  |  | 
|  | int validate_headref(const char *path) | 
|  | { | 
|  | struct stat st; | 
|  | char *buf, buffer[256]; | 
|  | unsigned char sha1[20]; | 
|  | int fd; | 
|  | ssize_t len; | 
|  |  | 
|  | if (lstat(path, &st) < 0) | 
|  | return -1; | 
|  |  | 
|  | /* Make sure it is a "refs/.." symlink */ | 
|  | if (S_ISLNK(st.st_mode)) { | 
|  | len = readlink(path, buffer, sizeof(buffer)-1); | 
|  | if (len >= 5 && !memcmp("refs/", buffer, 5)) | 
|  | return 0; | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Anything else, just open it and try to see if it is a symbolic ref. | 
|  | */ | 
|  | fd = open(path, O_RDONLY); | 
|  | if (fd < 0) | 
|  | return -1; | 
|  | len = read_in_full(fd, buffer, sizeof(buffer)-1); | 
|  | close(fd); | 
|  |  | 
|  | /* | 
|  | * Is it a symbolic ref? | 
|  | */ | 
|  | if (len < 4) | 
|  | return -1; | 
|  | if (!memcmp("ref:", buffer, 4)) { | 
|  | buf = buffer + 4; | 
|  | len -= 4; | 
|  | while (len && isspace(*buf)) | 
|  | buf++, len--; | 
|  | if (len >= 5 && !memcmp("refs/", buf, 5)) | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Is this a detached HEAD? | 
|  | */ | 
|  | if (!get_sha1_hex(buffer, sha1)) | 
|  | return 0; | 
|  |  | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | static char *user_path(char *buf, char *path, int sz) | 
|  | { | 
|  | struct passwd *pw; | 
|  | char *slash; | 
|  | int len, baselen; | 
|  |  | 
|  | if (!path || path[0] != '~') | 
|  | return NULL; | 
|  | path++; | 
|  | slash = strchr(path, '/'); | 
|  | if (path[0] == '/' || !path[0]) { | 
|  | pw = getpwuid(getuid()); | 
|  | } | 
|  | else { | 
|  | if (slash) { | 
|  | *slash = 0; | 
|  | pw = getpwnam(path); | 
|  | *slash = '/'; | 
|  | } | 
|  | else | 
|  | pw = getpwnam(path); | 
|  | } | 
|  | if (!pw || !pw->pw_dir || sz <= strlen(pw->pw_dir)) | 
|  | return NULL; | 
|  | baselen = strlen(pw->pw_dir); | 
|  | memcpy(buf, pw->pw_dir, baselen); | 
|  | while ((1 < baselen) && (buf[baselen-1] == '/')) { | 
|  | buf[baselen-1] = 0; | 
|  | baselen--; | 
|  | } | 
|  | if (slash && slash[1]) { | 
|  | len = strlen(slash); | 
|  | if (sz <= baselen + len) | 
|  | return NULL; | 
|  | memcpy(buf + baselen, slash, len + 1); | 
|  | } | 
|  | return buf; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * First, one directory to try is determined by the following algorithm. | 
|  | * | 
|  | * (0) If "strict" is given, the path is used as given and no DWIM is | 
|  | *     done. Otherwise: | 
|  | * (1) "~/path" to mean path under the running user's home directory; | 
|  | * (2) "~user/path" to mean path under named user's home directory; | 
|  | * (3) "relative/path" to mean cwd relative directory; or | 
|  | * (4) "/absolute/path" to mean absolute directory. | 
|  | * | 
|  | * Unless "strict" is given, we try access() for existence of "%s.git/.git", | 
|  | * "%s/.git", "%s.git", "%s" in this order.  The first one that exists is | 
|  | * what we try. | 
|  | * | 
|  | * Second, we try chdir() to that.  Upon failure, we return NULL. | 
|  | * | 
|  | * Then, we try if the current directory is a valid git repository. | 
|  | * Upon failure, we return NULL. | 
|  | * | 
|  | * If all goes well, we return the directory we used to chdir() (but | 
|  | * before ~user is expanded), avoiding getcwd() resolving symbolic | 
|  | * links.  User relative paths are also returned as they are given, | 
|  | * except DWIM suffixing. | 
|  | */ | 
|  | char *enter_repo(char *path, int strict) | 
|  | { | 
|  | static char used_path[PATH_MAX]; | 
|  | static char validated_path[PATH_MAX]; | 
|  |  | 
|  | if (!path) | 
|  | return NULL; | 
|  |  | 
|  | if (!strict) { | 
|  | static const char *suffix[] = { | 
|  | ".git/.git", "/.git", ".git", "", NULL, | 
|  | }; | 
|  | int len = strlen(path); | 
|  | int i; | 
|  | while ((1 < len) && (path[len-1] == '/')) { | 
|  | path[len-1] = 0; | 
|  | len--; | 
|  | } | 
|  | if (PATH_MAX <= len) | 
|  | return NULL; | 
|  | if (path[0] == '~') { | 
|  | if (!user_path(used_path, path, PATH_MAX)) | 
|  | return NULL; | 
|  | strcpy(validated_path, path); | 
|  | path = used_path; | 
|  | } | 
|  | else if (PATH_MAX - 10 < len) | 
|  | return NULL; | 
|  | else { | 
|  | path = strcpy(used_path, path); | 
|  | strcpy(validated_path, path); | 
|  | } | 
|  | len = strlen(path); | 
|  | for (i = 0; suffix[i]; i++) { | 
|  | strcpy(path + len, suffix[i]); | 
|  | if (!access(path, F_OK)) { | 
|  | strcat(validated_path, suffix[i]); | 
|  | break; | 
|  | } | 
|  | } | 
|  | if (!suffix[i] || chdir(path)) | 
|  | return NULL; | 
|  | path = validated_path; | 
|  | } | 
|  | else if (chdir(path)) | 
|  | return NULL; | 
|  |  | 
|  | if (access("objects", X_OK) == 0 && access("refs", X_OK) == 0 && | 
|  | validate_headref("HEAD") == 0) { | 
|  | setenv(GIT_DIR_ENVIRONMENT, ".", 1); | 
|  | check_repository_format(); | 
|  | return path; | 
|  | } | 
|  |  | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | int adjust_shared_perm(const char *path) | 
|  | { | 
|  | struct stat st; | 
|  | int mode; | 
|  |  | 
|  | if (!shared_repository) | 
|  | return 0; | 
|  | if (lstat(path, &st) < 0) | 
|  | return -1; | 
|  | mode = st.st_mode; | 
|  |  | 
|  | if (shared_repository) { | 
|  | int tweak = shared_repository; | 
|  | if (!(mode & S_IWUSR)) | 
|  | tweak &= ~0222; | 
|  | mode = (mode & ~0777) | tweak; | 
|  | } else { | 
|  | /* Preserve old PERM_UMASK behaviour */ | 
|  | if (mode & S_IWUSR) | 
|  | mode |= S_IWGRP; | 
|  | } | 
|  |  | 
|  | if (S_ISDIR(mode)) { | 
|  | mode |= FORCE_DIR_SET_GID; | 
|  |  | 
|  | /* Copy read bits to execute bits */ | 
|  | mode |= (shared_repository & 0444) >> 2; | 
|  | } | 
|  |  | 
|  | if ((mode & st.st_mode) != mode && chmod(path, mode) < 0) | 
|  | return -2; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const char *get_pwd_cwd(void) | 
|  | { | 
|  | static char cwd[PATH_MAX + 1]; | 
|  | char *pwd; | 
|  | struct stat cwd_stat, pwd_stat; | 
|  | if (getcwd(cwd, PATH_MAX) == NULL) | 
|  | return NULL; | 
|  | pwd = getenv("PWD"); | 
|  | if (pwd && strcmp(pwd, cwd)) { | 
|  | stat(cwd, &cwd_stat); | 
|  | if (!stat(pwd, &pwd_stat) && | 
|  | pwd_stat.st_dev == cwd_stat.st_dev && | 
|  | pwd_stat.st_ino == cwd_stat.st_ino) { | 
|  | strlcpy(cwd, pwd, PATH_MAX); | 
|  | } | 
|  | } | 
|  | return cwd; | 
|  | } | 
|  |  | 
|  | const char *make_nonrelative_path(const char *path) | 
|  | { | 
|  | static char buf[PATH_MAX + 1]; | 
|  |  | 
|  | if (is_absolute_path(path)) { | 
|  | if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) | 
|  | die ("Too long path: %.*s", 60, path); | 
|  | } else { | 
|  | const char *cwd = get_pwd_cwd(); | 
|  | if (!cwd) | 
|  | die("Cannot determine the current working directory"); | 
|  | if (snprintf(buf, PATH_MAX, "%s/%s", cwd, path) >= PATH_MAX) | 
|  | die ("Too long path: %.*s", 60, path); | 
|  | } | 
|  | return buf; | 
|  | } | 
|  |  | 
|  | const char *make_relative_path(const char *abs, const char *base) | 
|  | { | 
|  | static char buf[PATH_MAX + 1]; | 
|  | int baselen; | 
|  | if (!base) | 
|  | return abs; | 
|  | baselen = strlen(base); | 
|  | if (prefixcmp(abs, base)) | 
|  | return abs; | 
|  | if (abs[baselen] == '/') | 
|  | baselen++; | 
|  | else if (base[baselen - 1] != '/') | 
|  | return abs; | 
|  | strcpy(buf, abs + baselen); | 
|  | return buf; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * path = absolute path | 
|  | * buf = buffer of at least max(2, strlen(path)+1) bytes | 
|  | * It is okay if buf == path, but they should not overlap otherwise. | 
|  | * | 
|  | * Performs the following normalizations on path, storing the result in buf: | 
|  | * - Removes trailing slashes. | 
|  | * - Removes empty components. | 
|  | * - Removes "." components. | 
|  | * - Removes ".." components, and the components the precede them. | 
|  | * "" and paths that contain only slashes are normalized to "/". | 
|  | * Returns the length of the output. | 
|  | * | 
|  | * Note that this function is purely textual.  It does not follow symlinks, | 
|  | * verify the existence of the path, or make any system calls. | 
|  | */ | 
|  | int normalize_absolute_path(char *buf, const char *path) | 
|  | { | 
|  | const char *comp_start = path, *comp_end = path; | 
|  | char *dst = buf; | 
|  | int comp_len; | 
|  | assert(buf); | 
|  | assert(path); | 
|  |  | 
|  | while (*comp_start) { | 
|  | assert(*comp_start == '/'); | 
|  | while (*++comp_end && *comp_end != '/') | 
|  | ; /* nothing */ | 
|  | comp_len = comp_end - comp_start; | 
|  |  | 
|  | if (!strncmp("/",  comp_start, comp_len) || | 
|  | !strncmp("/.", comp_start, comp_len)) | 
|  | goto next; | 
|  |  | 
|  | if (!strncmp("/..", comp_start, comp_len)) { | 
|  | while (dst > buf && *--dst != '/') | 
|  | ; /* nothing */ | 
|  | goto next; | 
|  | } | 
|  |  | 
|  | memcpy(dst, comp_start, comp_len); | 
|  | dst += comp_len; | 
|  | next: | 
|  | comp_start = comp_end; | 
|  | } | 
|  |  | 
|  | if (dst == buf) | 
|  | *dst++ = '/'; | 
|  |  | 
|  | *dst = '\0'; | 
|  | return dst - buf; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * path = Canonical absolute path | 
|  | * prefix_list = Colon-separated list of absolute paths | 
|  | * | 
|  | * Determines, for each path in parent_list, whether the "prefix" really | 
|  | * is an ancestor directory of path.  Returns the length of the longest | 
|  | * ancestor directory, excluding any trailing slashes, or -1 if no prefix | 
|  | * is an ancestor.  (Note that this means 0 is returned if prefix_list is | 
|  | * "/".) "/foo" is not considered an ancestor of "/foobar".  Directories | 
|  | * are not considered to be their own ancestors.  path must be in a | 
|  | * canonical form: empty components, or "." or ".." components are not | 
|  | * allowed.  prefix_list may be null, which is like "". | 
|  | */ | 
|  | int longest_ancestor_length(const char *path, const char *prefix_list) | 
|  | { | 
|  | char buf[PATH_MAX+1]; | 
|  | const char *ceil, *colon; | 
|  | int len, max_len = -1; | 
|  |  | 
|  | if (prefix_list == NULL || !strcmp(path, "/")) | 
|  | return -1; | 
|  |  | 
|  | for (colon = ceil = prefix_list; *colon; ceil = colon+1) { | 
|  | for (colon = ceil; *colon && *colon != ':'; colon++); | 
|  | len = colon - ceil; | 
|  | if (len == 0 || len > PATH_MAX || !is_absolute_path(ceil)) | 
|  | continue; | 
|  | strlcpy(buf, ceil, len+1); | 
|  | len = normalize_absolute_path(buf, buf); | 
|  | /* Strip "trailing slashes" from "/". */ | 
|  | if (len == 1) | 
|  | len = 0; | 
|  |  | 
|  | if (!strncmp(path, buf, len) && | 
|  | path[len] == '/' && | 
|  | len > max_len) { | 
|  | max_len = len; | 
|  | } | 
|  | } | 
|  |  | 
|  | return max_len; | 
|  | } |