return (!stat(path, &st) && S_ISDIR(st.st_mode));
}
-/* We allow "recursive" symbolic links. Only within reason, though. */
-#define MAXDEPTH 5
+/* removes the last path component from 'path' except if 'path' is root */
+static void strip_last_component(struct strbuf *path)
+{
+ size_t offset = offset_1st_component(path->buf);
+ size_t len = path->len;
+
+ /* Find start of the last component */
+ while (offset < len && !is_dir_sep(path->buf[len - 1]))
+ len--;
+ /* Skip sequences of multiple path-separators */
+ while (offset < len && is_dir_sep(path->buf[len - 1]))
+ len--;
+
+ strbuf_setlen(path, len);
+}
+
+/* get (and remove) the next component in 'remaining' and place it in 'next' */
+static void get_next_component(struct strbuf *next, struct strbuf *remaining)
+{
+ char *start = NULL;
+ char *end = NULL;
+
+ strbuf_reset(next);
-const char *make_absolute_path(const char *path)
+ /* look for the next component */
+ /* Skip sequences of multiple path-separators */
+ for (start = remaining->buf; is_dir_sep(*start); start++)
+ ; /* nothing */
+ /* Find end of the path component */
+ for (end = start; *end && !is_dir_sep(*end); end++)
+ ; /* nothing */
+
+ strbuf_add(next, start, end - start);
+ /* remove the component from 'remaining' */
+ strbuf_remove(remaining, 0, end - remaining->buf);
+}
+
+/* copies root part from remaining to resolved, canonicalizing it on the way */
+static void get_root_part(struct strbuf *resolved, struct strbuf *remaining)
{
- static char bufs[2][PATH_MAX + 1], *buf = bufs[0], *next_buf = bufs[1];
- char cwd[1024] = "";
- int buf_index = 1;
+ int offset = offset_1st_component(remaining->buf);
+
+ strbuf_reset(resolved);
+ strbuf_add(resolved, remaining->buf, offset);
+#ifdef GIT_WINDOWS_NATIVE
+ convert_slashes(resolved->buf);
+#endif
+ strbuf_remove(remaining, 0, offset);
+}
+
+/* We allow "recursive" symbolic links. Only within reason, though. */
+#ifndef MAXSYMLINKS
+#define MAXSYMLINKS 32
+#endif
- int depth = MAXDEPTH;
- char *last_elem = NULL;
+/*
+ * Return the real path (i.e., absolute path, with symlinks resolved
+ * and extra slashes removed) equivalent to the specified path. (If
+ * you want an absolute path but don't mind links, use
+ * absolute_path().) Places the resolved realpath in the provided strbuf.
+ *
+ * The directory part of path (i.e., everything up to the last
+ * dir_sep) must denote a valid, existing directory, but the last
+ * component need not exist. If die_on_error is set, then die with an
+ * informative error message if there is a problem. Otherwise, return
+ * NULL on errors (without generating any output).
+ */
+char *strbuf_realpath(struct strbuf *resolved, const char *path,
+ int die_on_error)
+{
+ struct strbuf remaining = STRBUF_INIT;
+ struct strbuf next = STRBUF_INIT;
+ struct strbuf symlink = STRBUF_INIT;
+ char *retval = NULL;
+ int num_symlinks = 0;
struct stat st;
- if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
- die ("Too long path: %.*s", 60, path);
+ if (!*path) {
+ if (die_on_error)
+ die("The empty string is not a valid path");
+ else
+ goto error_out;
+ }
- while (depth--) {
- if (!is_directory(buf)) {
- char *last_slash = strrchr(buf, '/');
- if (last_slash) {
- *last_slash = '\0';
- last_elem = xstrdup(last_slash + 1);
- } else {
- last_elem = xstrdup(buf);
- *buf = '\0';
- }
+ strbuf_addstr(&remaining, path);
+ get_root_part(resolved, &remaining);
+
+ if (!resolved->len) {
+ /* relative path; can use CWD as the initial resolved path */
+ if (strbuf_getcwd(resolved)) {
+ if (die_on_error)
+ die_errno("unable to get current working directory");
+ else
+ goto error_out;
}
+ }
- if (*buf) {
- if (!*cwd && !getcwd(cwd, sizeof(cwd)))
- die_errno ("Could not get current working directory");
+ /* Iterate over the remaining path components */
+ while (remaining.len > 0) {
+ get_next_component(&next, &remaining);
- if (chdir(buf))
- die_errno ("Could not switch to '%s'", buf);
- }
- if (!getcwd(buf, PATH_MAX))
- die_errno ("Could not get current working directory");
-
- if (last_elem) {
- size_t len = strlen(buf);
- if (len + strlen(last_elem) + 2 > PATH_MAX)
- die ("Too long path name: '%s/%s'",
- buf, last_elem);
- buf[len] = '/';
- strcpy(buf + len + 1, last_elem);
- free(last_elem);
- last_elem = NULL;
+ if (next.len == 0) {
+ continue; /* empty component */
+ } else if (next.len == 1 && !strcmp(next.buf, ".")) {
+ continue; /* '.' component */
+ } else if (next.len == 2 && !strcmp(next.buf, "..")) {
+ /* '..' component; strip the last path component */
+ strip_last_component(resolved);
+ continue;
}
- if (!lstat(buf, &st) && S_ISLNK(st.st_mode)) {
- ssize_t len = readlink(buf, next_buf, PATH_MAX);
- if (len < 0)
- die_errno ("Invalid symlink '%s'", buf);
- if (PATH_MAX <= len)
- die("symbolic link too long: %s", buf);
- next_buf[len] = '\0';
- buf = next_buf;
- buf_index = 1 - buf_index;
- next_buf = bufs[buf_index];
- } else
- break;
+ /* append the next component and resolve resultant path */
+ if (!is_dir_sep(resolved->buf[resolved->len - 1]))
+ strbuf_addch(resolved, '/');
+ strbuf_addbuf(resolved, &next);
+
+ if (lstat(resolved->buf, &st)) {
+ /* error out unless this was the last component */
+ if (errno != ENOENT || remaining.len) {
+ if (die_on_error)
+ die_errno("Invalid path '%s'",
+ resolved->buf);
+ else
+ goto error_out;
+ }
+ } else if (S_ISLNK(st.st_mode)) {
+ ssize_t len;
+ strbuf_reset(&symlink);
+
+ if (num_symlinks++ > MAXSYMLINKS) {
+ errno = ELOOP;
+
+ if (die_on_error)
+ die("More than %d nested symlinks "
+ "on path '%s'", MAXSYMLINKS, path);
+ else
+ goto error_out;
+ }
+
+ len = strbuf_readlink(&symlink, resolved->buf,
+ st.st_size);
+ if (len < 0) {
+ if (die_on_error)
+ die_errno("Invalid symlink '%s'",
+ resolved->buf);
+ else
+ goto error_out;
+ }
+
+ if (is_absolute_path(symlink.buf)) {
+ /* absolute symlink; set resolved to root */
+ get_root_part(resolved, &symlink);
+ } else {
+ /*
+ * relative symlink
+ * strip off the last component since it will
+ * be replaced with the contents of the symlink
+ */
+ strip_last_component(resolved);
+ }
+
+ /*
+ * if there are still remaining components to resolve
+ * then append them to symlink
+ */
+ if (remaining.len) {
+ strbuf_addch(&symlink, '/');
+ strbuf_addbuf(&symlink, &remaining);
+ }
+
+ /*
+ * use the symlink as the remaining components that
+ * need to be resloved
+ */
+ strbuf_swap(&symlink, &remaining);
+ }
}
- if (*cwd && chdir(cwd))
- die_errno ("Could not change back to '%s'", cwd);
+ retval = resolved->buf;
+
+error_out:
+ strbuf_release(&remaining);
+ strbuf_release(&next);
+ strbuf_release(&symlink);
- return buf;
+ if (!retval)
+ strbuf_reset(resolved);
+
+ return retval;
}
-static const char *get_pwd_cwd(void)
+const char *real_path(const char *path)
{
- 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;
+ static struct strbuf realpath = STRBUF_INIT;
+ return strbuf_realpath(&realpath, path, 1);
}
-const char *make_nonrelative_path(const char *path)
+const char *real_path_if_valid(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_errno("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;
+ static struct strbuf realpath = STRBUF_INIT;
+ return strbuf_realpath(&realpath, path, 0);
+}
+
+char *real_pathdup(const char *path, int die_on_error)
+{
+ struct strbuf realpath = STRBUF_INIT;
+ char *retval = NULL;
+
+ if (strbuf_realpath(&realpath, path, die_on_error))
+ retval = strbuf_detach(&realpath, NULL);
+
+ strbuf_release(&realpath);
+
+ return retval;
+}
+
+/*
+ * Use this to get an absolute path from a relative one. If you want
+ * to resolve links, you should use real_path.
+ */
+const char *absolute_path(const char *path)
+{
+ static struct strbuf sb = STRBUF_INIT;
+ strbuf_reset(&sb);
+ strbuf_add_absolute_path(&sb, path);
+ return sb.buf;
+}
+
+char *absolute_pathdup(const char *path)
+{
+ struct strbuf sb = STRBUF_INIT;
+ strbuf_add_absolute_path(&sb, path);
+ return strbuf_detach(&sb, NULL);
+}
+
+char *prefix_filename(const char *pfx, const char *arg)
+{
+ struct strbuf path = STRBUF_INIT;
+ size_t pfx_len = pfx ? strlen(pfx) : 0;
+
+ if (!pfx_len)
+ ; /* nothing to prefix */
+ else if (is_absolute_path(arg))
+ pfx_len = 0;
+ else
+ strbuf_add(&path, pfx, pfx_len);
+
+ strbuf_addstr(&path, arg);
+#ifdef GIT_WINDOWS_NATIVE
+ convert_slashes(path.buf + pfx_len);
+#endif
+ return strbuf_detach(&path, NULL);
}