[svn-r17939] Description:

	Handle external links from symlinked files by adding another check to
look for "child" files for links from the actual location of the "parent" file,
instead of from the location of the symlink.

Tested on:
        FreeBSD/32 6.3 (duty) in debug mode
        FreeBSD/64 6.3 (liberty) w/C++ & FORTRAN, in debug mode
        Linux/32 2.6 (jam) w/PGI compilers, w/default API=1.8.x,
                w/C++ & FORTRAN, w/threadsafe, in debug mode
        Linux/64-amd64 2.6 (smirom) w/Intel compilers, w/default API=1.6.x,
                w/C++ & FORTRAN, in production mode
        Solaris/32 2.10 (linew) w/deprecated symbols disabled, w/C++ & FORTRAN,
                w/szip filter, in production mode
        Linux/64-ia64 2.6 (cobalt) w/Intel compilers, w/C++ & FORTRAN,
                in production mode
        Linux/64-ia64 2.4 (tg-login3) w/parallel, w/FORTRAN, in debug mode
        Linux/64-amd64 2.6 (abe) w/parallel, w/FORTRAN, in production mode
        Mac OS X/32 10.6.2 (amazon) in debug mode
        Mac OS X/32 10.6.2 (amazon) w/C++ & FORTRAN, w/threadsafe,
                in production mode

1 files changed, 122 insertions, 83 deletions

diff --git a/src/H5Lexternal.c b/src/H5Lexternal.c
index 640ac07..b99012c 100644
--- a/src/H5Lexternal.c
+++ b/src/H5Lexternal.c
@@ -202,18 +202,14 @@ H5L_extern_traverse(const char UNUSED *link_name, hid_t cur_group,
     size_t      fname_len;              /* Length of external link file name */
     unsigned    intent;                 /* File access permissions */
     H5L_elink_cb_t cb_info;             /* Callback info struct */
-    const char  *parent_file_name = NULL; /* Parent file name */
-    const char  *parent_group_name = NULL; /* Parent group name */
     hid_t       fapl_id = -1;           /* File access property list for external link's file */
     hid_t       ext_obj = -1;           /* ID for external link's object */
-    hid_t       ret_value;              /* Return value */
-
-    char        *tempname=NULL, *ptr=NULL, *extpath=NULL;
-    char        *env_prefix=NULL, *tmp_env_prefix=NULL;
-    char        *out_prefix_name=NULL, *pp=NULL;
-
-    H5P_genplist_t 	*fa_plist;      /* File access property list pointer */
+    char        *temp_group_name = NULL;/* Temporary pointer to group name */
+    char        *temp_file_name = NULL; /* Temporary pointer to file name */
+    char        *actual_file_name = NULL; /* Parent file's actual name */
+    H5P_genplist_t  *fa_plist;          /* File access property list pointer */
     H5F_close_degree_t 	fc_degree = H5F_CLOSE_WEAK;  /* File close degree for target file */
+    hid_t       ret_value;              /* Return value */
 
     FUNC_ENTER_NOAPI(H5L_extern_traverse, FAIL)
 
@@ -236,7 +232,7 @@ H5L_extern_traverse(const char UNUSED *link_name, hid_t cur_group,
     if(NULL == (plist = H5P_object_verify(lapl_id, H5P_LINK_ACCESS)))
         HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
 
-    /* get the fapl_id set for lapl_id if any */
+    /* Get the fapl_id set for lapl_id if any */
     if(H5P_get(plist, H5L_ACS_ELINK_FAPL_NAME, &fapl_id) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get fapl for links")
 
@@ -266,8 +262,11 @@ H5L_extern_traverse(const char UNUSED *link_name, hid_t cur_group,
 
     /* Make callback if it exists */
     if(cb_info.func) {
+        const char  *parent_file_name;  /* Parent file name */
+        const char  *parent_group_name; /* Parent group name */
+
         /* Get parent file name */
-        parent_file_name = H5F_NAME(loc.oloc->file);
+        parent_file_name = H5F_OPEN_NAME(loc.oloc->file);
 
         /* Get parent group name */
         if(loc.path->user_path_r != NULL && loc.path->obj_hidden == 0)
@@ -285,20 +284,19 @@ H5L_extern_traverse(const char UNUSED *link_name, hid_t cur_group,
             group_name_len++;
 
             /* Copy parent group name */
-            if(NULL == (tempname = (char *) H5MM_malloc((size_t) group_name_len)))
-                HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
-            if(H5G_get_name(cur_group, tempname, (size_t) group_name_len, lapl_id, H5AC_ind_dxpl_id) < 0)
+            if(NULL == (temp_group_name = (char *)H5MM_malloc((size_t)group_name_len)))
+                HGOTO_ERROR(H5E_LINK, H5E_NOSPACE, FAIL, "memory allocation failed")
+            if(H5G_get_name(cur_group, temp_group_name, (size_t) group_name_len, lapl_id, H5AC_ind_dxpl_id) < 0)
                 HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "unable to retrieve group name")
-            parent_group_name = tempname;
+            parent_group_name = temp_group_name;
         } /* end else */
 
         /* Make callback */
-        if((cb_info.func)(parent_file_name, parent_group_name, file_name, obj_name,
-                &intent, fapl_id, cb_info.user_data) < 0)
+        if((cb_info.func)(parent_file_name, parent_group_name, file_name, obj_name, &intent, fapl_id, cb_info.user_data) < 0)
             HGOTO_ERROR(H5E_LINK, H5E_CALLBACK, FAIL, "traversal operator failed")
 
-        /* Free tempname */
-        tempname = (char *)H5MM_xfree(tempname);
+        /* Free temp_group_name */
+        temp_group_name = (char *)H5MM_xfree(temp_group_name);
 
         /* Check access flags */
         if((intent & H5F_ACC_TRUNC) || (intent & H5F_ACC_EXCL))
@@ -312,88 +310,128 @@ H5L_extern_traverse(const char UNUSED *link_name, hid_t cur_group,
     /*
      * Start searching for the target file
      */
-    if ((tempname=H5MM_strdup(file_name)) == NULL)
+
+    /* Simplify intent flags for open calls */
+    intent = ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY);
+
+    /* Copy the file name to use */
+    if(NULL == (temp_file_name = H5MM_strdup(file_name)))
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
 
     /* target file_name is an absolute pathname: see RM for detailed description */
-    if (CHECK_ABSOLUTE(file_name) || CHECK_ABS_PATH(file_name)) {
-        if(NULL == (ext_file = H5F_open(file_name, ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY),
-                                H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id))) {
+    if(CHECK_ABSOLUTE(file_name) || CHECK_ABS_PATH(file_name)) {
+        /* Try opening file */
+        if(NULL == (ext_file = H5F_open(file_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id))) {
+            char *ptr = NULL;
+
             H5E_clear_stack(NULL);
+
             /* get last component of file_name */
 	    GET_LAST_DELIMITER(file_name, ptr)
 	    HDassert(ptr);
-	    HDstrcpy(tempname, ++ptr);
-        }
-    } else if (CHECK_ABS_DRIVE(file_name)) {
-        if(NULL == (ext_file = H5F_open(file_name, ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY),
-                                H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id))) {
+	    HDstrcpy(temp_file_name, ++ptr);
+        } /* end if */
+    } /* end if */
+    else if(CHECK_ABS_DRIVE(file_name)) {
+        if(NULL == (ext_file = H5F_open(file_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id))) {
             H5E_clear_stack(NULL);
 	    /* strip "<drive-letter>:" */
-	    HDstrcpy(tempname, &file_name[2]);
-	}
-    }
+	    HDstrcpy(temp_file_name, &file_name[2]);
+	} /* end if */
+    } /* end if */
 
     /* try searching from paths set in the environment variable */
-    if ((ext_file == NULL) && (env_prefix=HDgetenv("HDF5_EXT_PREFIX"))) {
-
-        if ((tmp_env_prefix = H5MM_strdup(env_prefix)) == NULL)
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
-	pp = tmp_env_prefix;
-
-        while ((tmp_env_prefix) && (*tmp_env_prefix)) {
-            out_prefix_name = H5L_getenv_prefix_name(&tmp_env_prefix/*in,out*/);
-            if ((out_prefix_name) && (*out_prefix_name)) {
-
-                if (H5L_build_name(out_prefix_name, tempname, &full_name/*out*/) < 0)
-                    HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "can't prepend prefix to filename")
-
-                ext_file = H5F_open(full_name, ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY),
-                            H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id);
-                if (full_name)
-                    H5MM_free(full_name);
-                if (ext_file != NULL)
-                    break;
-                H5E_clear_stack(NULL);
-            }
-        } /* end while */
-        pp = (char *)H5MM_xfree(pp);
-    }
+    if(ext_file == NULL) {
+        char *env_prefix;
+
+        if(NULL != (env_prefix = HDgetenv("HDF5_EXT_PREFIX"))) {
+            char *tmp_env_prefix;
+
+            if(NULL == (tmp_env_prefix = H5MM_strdup(env_prefix)))
+                HGOTO_ERROR(H5E_LINK, H5E_NOSPACE, FAIL, "memory allocation failed")
+
+            while((tmp_env_prefix) && (*tmp_env_prefix)) {
+                char *out_prefix_name;
+
+                out_prefix_name = H5L_getenv_prefix_name(&tmp_env_prefix/*in,out*/);
+                if(out_prefix_name && (*out_prefix_name)) {
+                    if(H5L_build_name(out_prefix_name, temp_file_name, &full_name/*out*/) < 0)
+                        HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "can't prepend prefix to filename")
+
+                    ext_file = H5F_open(full_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id);
+                    full_name = (char *)H5MM_xfree(full_name);
+                    if(ext_file != NULL)
+                        break;
+                    H5E_clear_stack(NULL);
+                } /* end if */
+            } /* end while */
+        } /* end if */
+    } /* end if */
 
     /* try searching from property list */
-    if (ext_file == NULL) {
+    if(ext_file == NULL) {
         if(H5P_get(plist, H5L_ACS_ELINK_PREFIX_NAME, &my_prefix) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get external link prefix")
-        if (my_prefix) {
-            if (H5L_build_name(my_prefix, tempname, &full_name/*out*/) < 0)
+        if(my_prefix) {
+            if(H5L_build_name(my_prefix, temp_file_name, &full_name/*out*/) < 0)
                 HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "can't prepend prefix to filename")
-            if ((ext_file=H5F_open(full_name, ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY),
-                        H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)) == NULL)
+            if(NULL == (ext_file = H5F_open(full_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)))
                 H5E_clear_stack(NULL);
-            if (full_name)
-                H5MM_free(full_name);
-        }
-    }
+            full_name = (char *)H5MM_xfree(full_name);
+        } /* end if */
+    } /* end if */
+
+    /* try searching from main file's "extpath": see description in H5F_open() & H5_build_extpath() */
+    if(ext_file == NULL) {
+        char *extpath;
+
+        if(NULL != (extpath = H5F_EXTPATH(loc.oloc->file))) {
+            if(H5L_build_name(extpath, temp_file_name, &full_name/*out*/) < 0)
+                HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "can't prepend prefix to filename")
+            if(NULL == (ext_file = H5F_open(full_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)))
+                H5E_clear_stack(NULL);
+            full_name = (char *)H5MM_xfree(full_name);
+        } /* end if */
+    } /* end if */
 
-    /* try searching from main file's "extpath":see description in H5F_open() & H5_build_extpath() */
-    if ((ext_file == NULL) && (extpath=H5F_EXTPATH(loc.oloc->file))) {
-        if (H5L_build_name(extpath, tempname, &full_name/*out*/) < 0)
-            HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "can't prepend prefix to filename")
-        if ((ext_file = H5F_open(full_name, ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY),
-                    H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)) == NULL)
+    /* try the relative file_name stored in temp_file_name */
+    if(ext_file == NULL) {
+        if(NULL == (ext_file = H5F_open(temp_file_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)))
             H5E_clear_stack(NULL);
-        if (full_name)
-            H5MM_free(full_name);
-    }
+    } /* end if */
 
-    /* try the relative file_name stored in tempname */
-    if (ext_file == NULL) {
-        if ((ext_file=H5F_open(tempname, ((intent & H5F_ACC_RDWR) ? H5F_ACC_RDWR : H5F_ACC_RDONLY),
-                        H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)) == NULL)
-            HGOTO_ERROR(H5E_LINK, H5E_CANTOPENFILE, FAIL, "unable to open external file")
-    }
+    /* try the 'resolved' name for the parent file (i.e. the name after symlinks
+     * were resolved)
+     */
+    if(ext_file == NULL) {
+        char *ptr = NULL;
+
+        /* Copy resolved file name */
+        if(NULL == (actual_file_name = H5MM_strdup(H5F_ACTUAL_NAME(loc.oloc->file))))
+            HGOTO_ERROR(H5E_LINK, H5E_CANTALLOC, FAIL, "can't duplicate resolved file name string")
+
+        /* get last component of file_name */
+        GET_LAST_DELIMITER(actual_file_name, ptr)
+        if(ptr) {
+            /* Truncate filename portion from actual file name path */
+            *ptr = '\0';
+
+            /* Build new file name for the external file */
+            if(H5L_build_name(actual_file_name, temp_file_name, &full_name/*out*/) < 0)
+                HGOTO_ERROR(H5E_LINK, H5E_CANTGET, FAIL, "can't prepend prefix to filename")
+        } /* end if */
+        else {
+            /* Transfer ownership of actual file name to 'full_name' variable */
+            full_name = actual_file_name;
+            actual_file_name = NULL;
+        } /* end else */
+
+        /* Try opening with the resolved name */
+        if(NULL == (ext_file = H5F_open(full_name, intent, H5P_FILE_CREATE_DEFAULT, fapl_id, H5AC_dxpl_id)))
+            HGOTO_ERROR(H5E_LINK, H5E_CANTOPENFILE, FAIL, "unable to open external file, external link file name = '%s', temp_file_name = '%s'", file_name, temp_file_name)
+        full_name = (char *)H5MM_xfree(full_name);
+    } /* end if */
 
-    tempname = (char *)H5MM_xfree(tempname);
 
     /* Increment the number of open objects, to hold the file open */
     H5F_incr_nopen_objs(ext_file);
@@ -425,11 +463,12 @@ done:
         HDONE_ERROR(H5E_ATOM, H5E_CANTRELEASE, FAIL, "unable to close atom for file access property list")
     if(ext_file && H5F_try_close(ext_file) < 0)
         HDONE_ERROR(H5E_LINK, H5E_CANTCLOSEFILE, FAIL, "problem closing external file")
+    full_name = (char *)H5MM_xfree(full_name);
+    temp_group_name = (char *)H5MM_xfree(temp_group_name);
+    temp_file_name = (char *)H5MM_xfree(temp_file_name);
+    actual_file_name = (char *)H5MM_xfree(actual_file_name);
 
     if(ret_value < 0) {
-        H5MM_xfree(tempname);
-        H5MM_xfree(pp);
-
         /* Close object if it's open and something failed */
         if(ext_obj >= 0 && H5I_dec_ref(ext_obj, FALSE) < 0)
             HDONE_ERROR(H5E_ATOM, H5E_CANTRELEASE, FAIL, "unable to close atom for external object")