BUG: Fix cifti_tool's CIFTI extension search, which never advanced

cifti/CMakeLists.txt

@@ -42,6 +42,15 @@ if(NIFTI_BUILD_TESTING AND NIFTI_BUILD_APPLICATIONS)
   set_tests_properties( ${TEST_PREFIX}_mim_summary_known_child
                         PROPERTIES PASS_REGULAR_EXPRESSION "BrainModel" )
 
+  # The CIFTI extension is found even when another extension precedes it.
+  add_test( NAME ${TEST_PREFIX}_tool_cext_not_first
+            COMMAND $<TARGET_FILE:${NIFTI_PACKAGE_PREFIX}cifti_tool>
+                    -input ${CMAKE_CURRENT_LIST_DIR}/testdata/cext_second_extension.nii
+                    -disp_cext )
+  set_tests_properties( ${TEST_PREFIX}_tool_cext_not_first
+            PROPERTIES PASS_REGULAR_EXPRESSION "<MapName>demo</MapName>"
+                       FAIL_REGULAR_EXPRESSION "no CIFTI extension" )
+
   # An extension payload that fills esize-8 with no NUL must not be read
   # past its end; the regex pins that the payload is still parsed.
   add_test( NAME ${TEST_PREFIX}_tool_unterminated_cext

cifti/cifti_tool.c

@@ -210,19 +210,22 @@ int disp_cifti_extension(nifti_image * nim, opts_t * opts)
               opts->fout ? opts->fout : "DEFAULT" );
 
    if( !nim ) return 1;
-   ext = nim->ext_list;
+   /* find the CIFTI extension, if any; it need not be first in the list */
+   ext = NULL;
    for( ind = 0; ind < nim->num_ext; ind++ )
-      if( ext->ecode == NIFTI_ECODE_CIFTI ) break;
+      if( nim->ext_list[ind].ecode == NIFTI_ECODE_CIFTI ) {
+         ext = nim->ext_list + ind;
+         break;
+      }
 
    fp = open_write_stream(opts->fout);
-   if( ext && ext->ecode != NIFTI_ECODE_CIFTI ) {
+   if( !ext ) {
       fprintf(fp, "** no CIFTI extension in %s\n",nim->fname?nim->fname:"NULL");
+      close_stream(fp);
       return 1;
    }
 
-   if(ext) {
-     fprintf(fp, "%.*s\n", ext->esize-8, ext->edata);
-   }
+   fprintf(fp, "%.*s\n", ext->esize-8, ext->edata);
 
    /* possibly close file */
    close_stream(fp);