csv: Better support separators other than comma or tab.

Before this commit, although any separator could be specified for cvs
output, the set of characters that triggered quoting was fixed, and only
really suitable for comma and tab separators.  This commit fixes the
problem, making sure that whenever the specified separator appears in a
field, that field will be quoted.

Problem noticed during a discussion with Björn Manke <bjoernmanke@gmx.net>
on pspp-users.

diff --git a/src/output/csv.c b/src/output/csv.c
index c648bfa79c30ae0e9330f3f7bae60290e1d96210..3fbf53d963448b041d403c81f2e4cd13fe6ad227 100644 (file)
--- a/src/output/csv.c
+++ b/src/output/csv.c
@@ -43,7 +43,8 @@ struct csv_driver
   {
     struct output_driver driver;
 
-    char *separator;            /* Comma or tab. */
+    char *separator;            /* Field separator (usually comma or tab). */
+    char *quote_set;            /* Characters that force quoting. */
     char *file_name;            /* Output file name. */
     char *command_name;         /* Current command. */
     FILE *file;                 /* Output file. */
@@ -78,6 +79,7 @@ csv_create (const char *file_name, enum settings_output_devices device_type,
   output_driver_init (&csv->driver, &csv_driver_class, file_name, device_type);
 
   csv->separator = parse_string (opt (d, o, "separator", ","));
+  csv->quote_set = xasprintf ("\"\n\r\t%s", csv->separator);
   csv->file_name = xstrdup (file_name);
   csv->file = fn_open (csv->file_name, "w");
   csv->n_items = 0;
@@ -101,6 +103,7 @@ csv_destroy (struct output_driver *driver)
     fn_close (csv->file_name, csv->file);
 
   free (csv->separator);
+  free (csv->quote_set);
   free (csv->file_name);
   free (csv);
 }
@@ -114,34 +117,34 @@ csv_flush (struct output_driver *driver)
 }
 
 static void
-csv_output_field (FILE *file, const char *field)
+csv_output_field (struct csv_driver *csv, const char *field)
 {
   while (*field == ' ')
     field++;
 
-  if (field[strcspn (field, "\"\n\r,\t")])
+  if (field[strcspn (field, csv->quote_set)])
     {
       const char *p;
 
-      putc ('"', file);
+      putc ('"', csv->file);
       for (p = field; *p != '\0'; p++)
         {
           if (*p == '"')
-            putc ('"', file);
-          putc (*p, file);
+            putc ('"', csv->file);
+          putc (*p, csv->file);
         }
-      putc ('"', file);
+      putc ('"', csv->file);
     }
   else
-    fputs (field, file);
+    fputs (field, csv->file);
 }
 
 static void
-csv_output_field_format (FILE *file, const char *format, ...)
+csv_output_field_format (struct csv_driver *csv, const char *format, ...)
   PRINTF_FORMAT (2, 3);
 
 static void
-csv_output_field_format (FILE *file, const char *format, ...)
+csv_output_field_format (struct csv_driver *csv, const char *format, ...)
 {
   va_list args;
   char *s;
@@ -150,7 +153,7 @@ csv_output_field_format (FILE *file, const char *format, ...)
   s = xvasprintf (format, args);
   va_end (args);
 
-  csv_output_field (file, s);
+  csv_output_field (csv, s);
   free (s);
 }
 
@@ -180,7 +183,7 @@ csv_submit (struct output_driver *driver,
 
       if (caption != NULL)
         {
-          csv_output_field_format (csv->file, "Table: %s", caption);
+          csv_output_field_format (csv, "Table: %s", caption);
           putc ('\n', csv->file);
         }
 
@@ -196,9 +199,9 @@ csv_submit (struct output_driver *driver,
                 fputs (csv->separator, csv->file);
 
               if (x != cell.d[TABLE_HORZ][0] || y != cell.d[TABLE_VERT][0])
-                csv_output_field (csv->file, "");
+                csv_output_field (csv, "");
               else
-                csv_output_field (csv->file, cell.contents);
+                csv_output_field (csv, cell.contents);
 
               table_cell_free (&cell);
             }
@@ -219,15 +222,15 @@ csv_submit (struct output_driver *driver,
       switch (type)
         {
         case TEXT_ITEM_TITLE:
-          csv_output_field_format (csv->file, "Title: %s", text);
+          csv_output_field_format (csv, "Title: %s", text);
           break;
 
         case TEXT_ITEM_SUBTITLE:
-          csv_output_field_format (csv->file, "Subtitle: %s", text);
+          csv_output_field_format (csv, "Subtitle: %s", text);
           break;
 
         default:
-          csv_output_field (csv->file, text);
+          csv_output_field (csv, text);
           break;
         }
       putc ('\n', csv->file);
@@ -238,7 +241,7 @@ csv_submit (struct output_driver *driver,
       const struct msg *msg = message_item_get_msg (message_item);
       char *s = msg_to_string (msg, csv->command_name);
       csv_put_separator (csv);
-      csv_output_field (csv->file, s);
+      csv_output_field (csv, s);
       free (s);
       putc ('\n', csv->file);
     }