Use standard realpath(3).

These days we may rely on the POSIX 2008 semantics of this function,
so remove our open-coded version.

diff --git a/ipc.c b/ipc.c
index 9b38c1318541d24a5686c76eccfc330a3a204177..4aef302604cb1d80c65839148ece4372d48f6f99 100644 (file)
--- a/ipc.c
+++ b/ipc.c
@@ -78,158 +78,6 @@ static uint32_t super_fast_hash(const uint8_t *data, uint32_t len, uint32_t hash
        return hash;
 }
 
-/*
- * Return the canonical absolute name of a given file name.
- *
- * Slightly modified version of glibc's realpath, Copyright (C)
- * 1996-2002,2004,2005,2006,2008 Free Software Foundation, Inc.
- *
- * A canonical name does not contain any `.', `..' components nor any repeated
- * path separators ('/') or symlinks. All path components must exist. The
- * result is malloc'd and must be freed by the caller.
- */
-static int dss_realpath(const char *name, char **resolved_path)
-{
-       char *rpath = NULL, *dest, *extra_buf = NULL;
-       const char *start, *end, *rpath_limit;
-       long int path_max;
-       int ret, num_links = 0;
-
-       if (name[0] == '\0') {
-               /*
-                * As per Single Unix Specification V2 we must return an error
-                * if the name argument points to an empty string.
-                */
-               ret = -ERRNO_TO_DSS_ERROR(ENOENT);
-               goto error;
-       }
-#ifdef PATH_MAX
-       path_max = PATH_MAX;
-#else
-       /*
-        * From realpath(3): Asking pathconf(3) does not really help, since on
-        * the one hand POSIX warns that the result of pathconf(3) may be
-        * huge and unsuitable for mallocing memory. And on the other hand
-        * pathconf(3) may return -1 to signify that PATH_MAX is not bounded.
-        */
-       path_max = pathconf(name, _PC_PATH_MAX);
-       if (path_max <= 0 || path_max >= 4096)
-               path_max = 4096;
-#endif
-       rpath = dss_malloc(path_max);
-       rpath_limit = rpath + path_max;
-
-       if (name[0] != '/') {
-               if (!getcwd(rpath, path_max)) {
-                       ret = -ERRNO_TO_DSS_ERROR(errno);
-                       goto error;
-               }
-               dest = memchr(rpath, '\0', path_max);
-       } else {
-               rpath[0] = '/';
-               dest = rpath + 1;
-       }
-
-       for (start = end = name; *start; start = end) {
-               struct stat st;
-               int n;
-
-               /* Skip sequence of multiple path-separators.  */
-               while (*start == '/')
-                       ++start;
-
-               /* Find end of path component.  */
-               for (end = start; *end && *end != '/'; ++end)
-                       /* Nothing.  */ ;
-
-               if (end - start == 0)
-                       break;
-               else if (end - start == 1 && start[0] == '.')
-                       /* nothing */ ;
-               else if (end - start == 2 && start[0] == '.' && start[1] == '.') {
-                       /* Back up to previous component, ignore if at root already.  */
-                       if (dest > rpath + 1)
-                               while ((--dest)[-1] != '/') ;
-               } else {
-                       size_t new_size;
-
-                       if (dest[-1] != '/')
-                               *dest++ = '/';
-
-                       if (dest + (end - start) >= rpath_limit) {
-                               ptrdiff_t dest_offset = dest - rpath;
-
-                               new_size = rpath_limit - rpath;
-                               if (end - start + 1 > path_max)
-                                       new_size += end - start + 1;
-                               else
-                                       new_size += path_max;
-                               rpath = dss_realloc(rpath, new_size);
-                               rpath_limit = rpath + new_size;
-                               dest = rpath + dest_offset;
-                       }
-
-                       memcpy(dest, start, end - start);
-                       dest += end - start;
-                       *dest = '\0';
-
-                       if (stat(rpath, &st) < 0) {
-                               ret = -ERRNO_TO_DSS_ERROR(errno);
-                               goto error;
-                       }
-
-                       if (S_ISLNK(st.st_mode)) {
-                               char *buf = alloca(path_max);
-                               size_t len;
-
-                               if (++num_links > MAXSYMLINKS) {
-                                       ret = -ERRNO_TO_DSS_ERROR(ELOOP);
-                                       goto error;
-                               }
-
-                               n = readlink(rpath, buf, path_max - 1);
-                               if (n < 0) {
-                                       ret = -ERRNO_TO_DSS_ERROR(errno);
-                                       goto error;
-                               }
-                               buf[n] = '\0';
-
-                               if (!extra_buf)
-                                       extra_buf = alloca(path_max);
-
-                               len = strlen(end);
-                               if ((long int) (n + len) >= path_max) {
-                                       ret = -ERRNO_TO_DSS_ERROR(ENAMETOOLONG);
-                                       goto error;
-                               }
-
-                               /* Careful here, end may be a pointer into extra_buf... */
-                               memmove(&extra_buf[n], end, len + 1);
-                               end = memcpy(extra_buf, buf, n);
-
-                               if (buf[0] == '/') /* It's an absolute symlink */
-                                       dest = rpath + 1;
-                               else /* Back up to previous component, ignore if at root already: */
-                                       if (dest > rpath + 1)
-                                               while ((--dest)[-1] != '/')
-                                                       ; /* nothing */
-                       } else if (!S_ISDIR(st.st_mode) && *end != '\0') {
-                               ret = -ERRNO_TO_DSS_ERROR(ENOTDIR);
-                               goto error;
-                       }
-               }
-       }
-       if (dest > rpath + 1 && dest[-1] == '/')
-               --dest;
-       *dest = '\0';
-       *resolved_path = rpath;
-       return 1;
-error:
-       free(rpath);
-       *resolved_path = NULL;
-       return ret;
-}
-
 static int get_key_or_die(const char *config_file)
 {
        int ret;
@@ -238,10 +86,9 @@ static int get_key_or_die(const char *config_file)
 
        assert(config_file);
        if (stat(config_file, &statbuf) == 0) {
-               ret = dss_realpath(config_file, &rpath);
-               if (ret < 0) {
-                       DSS_EMERG_LOG(("could not resolve path %s: %s\n", config_file,
-                               dss_strerror(-ret)));
+               rpath = realpath(config_file, NULL);
+               if (!rpath) {
+                       DSS_EMERG_LOG(("could not resolve path %s: %m\n", config_file));
                        exit(EXIT_FAILURE);
                }
                DSS_DEBUG_LOG(("resolved path: %s\n", rpath));