From 27d73ca503b2e508c682fca2848f8ae38390a146 Mon Sep 17 00:00:00 2001 From: Shehjar Tikoo Date: Thu, 16 Apr 2009 23:58:50 -0700 Subject: libglusterfsclient: Add realpath API Signed-off-by: Anand V. Avati --- libglusterfsclient/src/libglusterfsclient.c | 184 ++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) (limited to 'libglusterfsclient') diff --git a/libglusterfsclient/src/libglusterfsclient.c b/libglusterfsclient/src/libglusterfsclient.c index 9866af491e1..bc2f7c4d702 100755 --- a/libglusterfsclient/src/libglusterfsclient.c +++ b/libglusterfsclient/src/libglusterfsclient.c @@ -42,6 +42,7 @@ #include "compat-errno.h" #include #include +#include #define LIBGF_XL_NAME "libglusterfsclient" #define LIBGLUSTERFS_INODE_TABLE_LRU_LIMIT 1000 //14057 @@ -4823,6 +4824,189 @@ out: return op_ret; } +char * +glusterfs_realpath (glusterfs_handle_t handle, const char *path, + char *resolved_path) +{ + char *buf = NULL, *extra_buf = NULL; + char *rpath = NULL; + char *start = NULL, *end = NULL; + char *dest = NULL; + libglusterfs_client_ctx_t *ctx = handle; + long int path_max = 0; + char *ptr = NULL; + struct stat stbuf = {0, }; + long int new_size = 0; + char *new_rpath = NULL; + int dest_offset = 0; + char *rpath_limit = 0; + int ret = 0, num_links = 0; + size_t len = 0; + + GF_VALIDATE_OR_GOTO (LIBGF_XL_NAME, ctx, out); + GF_VALIDATE_ABSOLUTE_PATH_OR_GOTO (LIBGF_XL_NAME, path, out); + +#ifdef PATH_MAX + path_max = PATH_MAX; +#else + path_max = pathconf (path, _PC_PATH_MAX); + if (path_max <= 0) { + path_max = 1024; + } +#endif + + if (resolved_path == NULL) { + rpath = CALLOC (1, path_max); + if (rpath == NULL) { + errno = ENOMEM; + goto out; + } + } else { + rpath = resolved_path; + } + + rpath_limit = rpath + path_max; + + if (path[0] == '/') { + rpath[0] = '/'; + dest = rpath + 1; + } else { + /* + FIXME: can $CWD be a valid path on glusterfs server? hence is + it better to handle this case or just return EINVAL for + relative paths? + */ + ptr = getcwd (rpath, path_max); + if (ptr == NULL) { + goto err; + } + dest = rpath + strlen (rpath); + } + + for (start = end = (char *)path; *end; start = end) { + if (dest[-1] != '/') { + *dest++ = '/'; + } + + while (*start == '/') { + start++; + } + + for (end = start; *end && *end != '/'; end++); + + if ((end - start) == 0) { + break; + } + + if ((end - start == 1) && (start[0] == '.')) { + /* do nothing */ + } else if (((end - start) == 2) && (start[0] == '.') + && (start[1] == '.')) { + if (dest > rpath + 1) { + while (--dest[-1] != '/'); + } + } else { + if ((dest + (end - start + 1)) >= rpath_limit) { + if (resolved_path == NULL) { + errno = ENAMETOOLONG; + if (dest > rpath + 1) + dest--; + *dest = '\0'; + goto err; + } + + 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; + } + + new_rpath = realloc (rpath, new_size); + if (new_rpath == NULL) { + goto err; + } + + + dest = new_rpath + dest_offset; + rpath = new_rpath; + rpath_limit = rpath + new_size; + } + + memcpy (dest, start, end - start); + dest += end - start; + *dest = '\0'; + + /* posix_stat is implemented using lstat */ + ret = glusterfs_stat (handle, rpath, &stbuf); + if (ret == -1) { + gf_log ("libglusterfsclient", GF_LOG_ERROR, + "glusterfs_stat returned -1 for path" + " (%s):(%s)", rpath, strerror (errno)); + goto err; + } + + if (S_ISLNK (stbuf.st_mode)) { + buf = alloca (path_max); + + if (++num_links > MAXSYMLINKS) + { + errno = ELOOP; + goto err; + } + + ret = glusterfs_readlink (handle, rpath, buf, + path_max - 1); + if (ret < 0) { + gf_log ("libglusterfsclient", + GF_LOG_ERROR, + "glusterfs_readlink returned %d" + " for path (%s):(%s)", + ret, rpath, strerror (errno)); + goto err; + } + buf[ret] = '\0'; + + if (extra_buf == NULL) + extra_buf = alloca (path_max); + + len = strlen (end); + if ((long int) (ret + len) >= path_max) + { + errno = ENAMETOOLONG; + goto err; + } + + memmove (&extra_buf[ret], end, len + 1); + path = end = memcpy (extra_buf, buf, ret); + + if (buf[0] == '/') + dest = rpath + 1; + else + if (dest > rpath + 1) + while ((--dest)[-1] != '/'); + } else if (!S_ISDIR (stbuf.st_mode) && *end != '\0') { + errno = ENOTDIR; + goto err; + } + } + } + if (dest > rpath + 1 && dest[-1] == '/') + --dest; + *dest = '\0'; + +out: + return rpath; + +err: + if (resolved_path == NULL) { + FREE (rpath); + } + + return NULL; +} + static struct xlator_fops libgf_client_fops = { }; -- cgit