diff options
Diffstat (limited to 'libglusterfs/src/common-utils.c')
| -rw-r--r-- | libglusterfs/src/common-utils.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/libglusterfs/src/common-utils.c b/libglusterfs/src/common-utils.c index 0f1aceec39b..1318c4d49a6 100644 --- a/libglusterfs/src/common-utils.c +++ b/libglusterfs/src/common-utils.c @@ -3429,3 +3429,130 @@ fop_log_level (glusterfs_fop_t fop, int op_errno) return GF_LOG_ERROR; } + +/* This function will build absolute path of file/directory from the + * current location and relative path given from the current location + * For example consider our current path is /a/b/c/ and relative path + * from current location is ./../x/y/z .After parsing through this + * function the absolute path becomes /a/b/x/y/z/. + * + * The function gives a pointer to absolute path if it is successful + * and also returns zero. + * Otherwise function gives NULL pointer with returning an err value. + * + * So the user need to free memory allocated for path. + * + */ + +int32_t +gf_build_absolute_path (char *current_path, char *relative_path, char **path) +{ + char *absolute_path = NULL; + char *token = NULL; + char *component = NULL; + char *saveptr = NULL; + char *end = NULL; + int ret = 0; + size_t relativepath_len = 0; + size_t currentpath_len = 0; + size_t max_absolutepath_len = 0; + + GF_ASSERT (current_path); + GF_ASSERT (relative_path); + GF_ASSERT (path); + + if (!path || !current_path || !relative_path) { + ret = -EFAULT; + goto err; + } + /* Check for current and relative path + * current path should be absolute one and start from '/' + * relative path should not start from '/' + */ + currentpath_len = strlen (current_path); + if (current_path[0] != '/' || (currentpath_len > PATH_MAX)) { + gf_log (THIS->name, GF_LOG_ERROR, "Wrong value for" + " current path %s", current_path); + ret = -EINVAL; + goto err; + } + + relativepath_len = strlen (relative_path); + if (relative_path[0] == '/' || (relativepath_len > PATH_MAX)) { + gf_log (THIS->name, GF_LOG_ERROR, "Wrong value for" + " relative path %s", relative_path); + ret = -EINVAL; + goto err; + } + + /* It is maximum possible value for absolute path */ + max_absolutepath_len = currentpath_len + relativepath_len + 2; + + absolute_path = GF_CALLOC (1, max_absolutepath_len, gf_common_mt_char); + if (!absolute_path) { + ret = -ENOMEM; + goto err; + } + absolute_path[0] = '\0'; + + /* If current path is root i.e contains only "/", we do not + * need to copy it + */ + if (strcmp (current_path, "/") != 0) { + strcpy (absolute_path, current_path); + + /* We trim '/' at the end for easier string manipulation */ + gf_path_strip_trailing_slashes (absolute_path); + } + + /* Used to spilt relative path based on '/' */ + component = gf_strdup (relative_path); + if (!component) { + ret = -ENOMEM; + goto err; + } + + /* In the relative path, we want to consider ".." and "." + * if token is ".." , we just need to reduce one level hierarchy + * if token is "." , we just ignore it + * if token is NULL , end of relative path + * if absolute path becomes '\0' and still "..", then it is a bad + * relative path, it points to out of boundary area and stop + * building the absolute path + * All other cases we just concatenate token to the absolute path + */ + for (token = strtok_r (component, "/", &saveptr), + end = strchr (absolute_path, '\0'); token; + token = strtok_r (NULL, "/", &saveptr)) { + if (strcmp (token, ".") == 0) + continue; + + else if (strcmp (token, "..") == 0) { + + if (absolute_path[0] == '\0') { + ret = -EACCES; + goto err; + } + + end = strrchr (absolute_path, '/'); + *end = '\0'; + } else { + ret = snprintf (end, max_absolutepath_len - + strlen (absolute_path), "/%s", token); + end = strchr (absolute_path , '\0'); + } + } + + if (strlen (absolute_path) > PATH_MAX) { + ret = -EINVAL; + goto err; + } + *path = gf_strdup (absolute_path); + +err: + if (component) + GF_FREE (component); + if (absolute_path) + GF_FREE (absolute_path); + return ret; +} |