Fix handling of '/' characters in names in DAP2.

re: Unidata/thredds#1224
[note that this is an issue in thredds, but the fix is in netcdf-c]

A thredds server can encode a netcdf-4 file into DAP2
by flattening names to include the containing group path,
where the group names are separated by '/'.

But the '/' is prohibited in netcdf names even if escaped
(a decision before my time).

So, if the netcdf-c/libdap2 code encounters a DAP2 name with '/'
characters, the '/' characters are converted to the string
%2f. Unfortunately, there is a glitch, namely that converting
the leading '/' produces a name that is still illegal. This PR
modifies the code to just drop the leading '/' character.

CMakeLists.txt

@@ -846,13 +846,6 @@ OPTION(ENABLE_DAP_LONG_TESTS "Enable DAP long tests." OFF)
 OPTION(ENABLE_DAP_REMOTE_TESTS "Enable DAP remote tests." ON)
 SET(REMOTETESTSERVERS "149.165.169.123:8080,remotetest.unidata.ucar.edu" CACHE STRING "test servers to use for remote test")
 
-# If netCDF4 and DAP, Option for DAP groups.
-IF(ENABLE_NETCDF_4 AND ENABLE_DAP2)
-  OPTION(ENABLE_DAP_GROUPS "Whether netcdf4 group names should be enabled." ON)
-ELSE()
-  SET(ENABLE_DAP_GROUPS OFF CACHE BOOL "Whether netcdf4 group names should be enabled.")
-ENDIF()
-
 # Enable some developer-only tests
 OPTION(ENABLE_EXTRA_TESTS "Enable Extra tests. Some may not work because of known issues. Developers only." OFF)
 IF(ENABLE_EXTRA_TESTS)

config.h.cmake.in

@@ -132,9 +132,6 @@ are set when opening a binary file on Windows. */
 /* if true, build DAP4 Client */
 #cmakedefine ENABLE_DAP4 1
 
-/* if true, enable DAP group names */
-#cmakedefine ENABLE_DAP_GROUPS 1
-
 /* if true, do remote tests */
 #cmakedefine ENABLE_DAP_REMOTE_TESTS 1
 

configure.ac

@@ -395,21 +395,6 @@ if test "x$enable_dap_remote_tests" = "xno" ; then
 fi
 AC_MSG_RESULT($enable_dap_auth_tests)
 
-# Control if groups are supported in [netcdf4]dap2 code
-AC_MSG_CHECKING([whether [netcdf4] group names for DAP2 should be enabled (default on)])
-AC_ARG_ENABLE([dap-groups],
-              [AS_HELP_STRING([--disable-dap-groups],
-                                 [disable [netcdf4] DAP2 group names])])
-test "x$enable_dap_groups" = xno || enable_dap_groups=yes
-AC_MSG_RESULT($enable_dap_groups)
-if test "x$enable_dap" = "xno" ; then
-  AC_MSG_NOTICE([DAP2 groups is being disabled because DAP2 support is  disabled or netcdf-4 disabled])
-  enable_dap_groups=no
-fi
-if test "x$enable_dap_groups" = xyes; then
-AC_DEFINE([ENABLE_DAP_GROUPS], [1], [if true, enable DAP group names])
-fi
-
 # Did the user specify a list of test servers to try for remote tests?
 AC_MSG_CHECKING([which remote test server(s) to use])
 AC_ARG_WITH([testservers],

libdap2/daputil.c

@@ -34,6 +34,8 @@ names to %2f.
 char*
 cdflegalname(char* name)
 {
+    if(name != NULL && name[0] == '/')
+	name = name+1; /* remove leading / so name will be legal */
     return repairname(name,"/");
 }
 
@@ -733,13 +735,15 @@ dap_badname(char* name)
     return 0;
 }
 
+#if 0
 /* Repair a dap name */
 char*
 dap_repairname(char* name)
 {
     /* assume that dap_badname was called on this name and returned 1 */
     return repairname(name,baddapchars);
 }
+#endif
 
 /* Check a name to see if it contains illegal dap characters
    and repair them

libdap4/d4varx.c

@@ -46,7 +46,7 @@ NCD4_get_vars(int ncid, int varid,
     size_t dstcount;
 
     if((ret=getvarx(ncid, varid, &info, &ncvar, &xtype, &xsize, &nc4type, &nc4size)))
-	{THROW(ret); goto done;}
+	{goto done;}
 
     meta = info->substrate.metadata;
     nctype = ncvar->basetype;
@@ -91,17 +91,17 @@ NCD4_get_vars(int ncid, int varid,
             offset = ncvar->data.dap4data.memory;
 	    /* We have to walk to the count'th location in the data */
 	    if((ret=NCD4_moveto(meta,ncvar,count,&offset)))
-	        {THROW(ret); goto done;}		    
+	        {goto done;}		    
 	}
 	dst = instance;
 	if((ret=NCD4_fillinstance(meta,nctype,&offset,&dst,blobs)))
-	    {THROW(ret); goto done;}
+	    {goto done;}
 	if(xtype == nc4type) {
 	    /* We can just copy out the data */
 	    memcpy(xpos,instance,nc4size);
 	} else { /* Need to convert */
 	    if((ret=NCD4_convert(nc4type,xtype,xpos,instance,1)))
-	        {THROW(ret); goto done;}
+	        {goto done;}
 	}
     }
 
@@ -136,7 +136,7 @@ getvarx(int ncid, int varid, NCD4INFO** infop, NCD4node** varp,
     int grp_id;
 
     if((ret = NC_check_id(ncid, (NC**)&ncp)) != NC_NOERR)
-	{THROW(ret); goto done;}
+	goto done;
 
     info = getdap(ncp);
     if(info == NULL)