From: John Darrington <john@darrington.wattle.id.au>
Date: Sun, 8 Dec 2013 14:36:49 +0000 (+0100)
Subject: src/data/any-reader.c (any_reader_may_open): Return tri-state value.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=41b0d9a7203d396cf1514459afa4722ab5ae8ded;p=pspp

src/data/any-reader.c (any_reader_may_open): Return tri-state value.

Previously, any_reader_may_open returned bool.  This change makes it
return a tri-state variable. YES, NO or ERROR.  This is useful to
distinguish between a file which is not "readable" (ie not in a format
which PSPP knows how to read) and a file which cannot be opened due
to lack of permission or other lower level errors.
---

diff --git a/src/data/any-reader.c b/src/data/any-reader.c
index 1b488f208a..eaec63da94 100644
--- a/src/data/any-reader.c
+++ b/src/data/any-reader.c
@@ -38,14 +38,6 @@
 #include "gettext.h"
 #define _(msgid) gettext (msgid)
 
-/* Result of type detection. */
-enum detect_result
-  {
-    YES,                        /* It is this type. */
-    NO,                         /* It is not this type. */
-    IO_ERROR                    /* File couldn't be opened. */
-  };
-
 /* Tries to detect whether FILE is a given type of file, by opening the file
    and passing it to DETECT, and returns a detect_result. */
 static enum detect_result
@@ -59,23 +51,27 @@ try_detect (const char *file_name, bool (*detect) (FILE *))
     {
       msg (ME, _("An error occurred while opening `%s': %s."),
            file_name, strerror (errno));
-      return IO_ERROR;
+      return ANY_ERROR;
     }
 
   is_type = detect (file);
 
   fn_close (file_name, file);
 
-  return is_type ? YES : NO;
+  return is_type ? ANY_YES : ANY_NO;
 }
 
 /* Returns true if any_reader_open() would be able to open FILE as a data
    file, false otherwise. */
-bool
+enum detect_result
 any_reader_may_open (const char *file)
 {
-  return (try_detect (file, sfm_detect) == YES
-          || try_detect (file, pfm_detect) == YES);
+  enum detect_result res = try_detect (file, sfm_detect);
+  
+  if (res == ANY_NO)
+    res = try_detect (file, pfm_detect);
+
+  return res;
 }
 
 /* Returns a casereader for HANDLE.  On success, returns the new
@@ -97,15 +93,15 @@ any_reader_open (struct file_handle *handle, const char *encoding,
         enum detect_result result;
 
         result = try_detect (fh_get_file_name (handle), sfm_detect);
-        if (result == IO_ERROR)
+        if (result == ANY_ERROR)
           return NULL;
-        else if (result == YES)
+        else if (result == ANY_YES)
           return sfm_open_reader (handle, encoding, dict, NULL);
 
         result = try_detect (fh_get_file_name (handle), pfm_detect);
-        if (result == IO_ERROR)
+        if (result == ANY_ERROR)
           return NULL;
-        else if (result == YES)
+        else if (result == ANY_YES)
           return pfm_open_reader (handle, dict, NULL);
 
         msg (SE, _("`%s' is not a system or portable file."),
diff --git a/src/data/any-reader.h b/src/data/any-reader.h
index fb36e99cce..063a7e650e 100644
--- a/src/data/any-reader.h
+++ b/src/data/any-reader.h
@@ -19,9 +19,18 @@
 
 #include <stdbool.h>
 
+/* Result of type detection. */
+enum detect_result
+  {
+    ANY_YES,                        /* It is this type. */
+    ANY_NO,                         /* It is not this type. */
+    ANY_ERROR                    /* File couldn't be opened. */
+  };
+
+
 struct file_handle;
 struct dictionary;
-bool any_reader_may_open (const char *file_name);
+enum detect_result any_reader_may_open (const char *file_name);
 struct casereader *any_reader_open (struct file_handle *, const char *encoding,
                                     struct dictionary **);
 
diff --git a/src/ui/gui/psppire-window.c b/src/ui/gui/psppire-window.c
index 65842bdc62..84211133de 100644
--- a/src/ui/gui/psppire-window.c
+++ b/src/ui/gui/psppire-window.c
@@ -703,7 +703,7 @@ on_selection_changed (GtkFileChooser *chooser, GtkWidget *encoding_selector)
       return;
     }
 
-  gtk_widget_set_sensitive (encoding_selector, ! any_reader_may_open (sysname));
+  gtk_widget_set_sensitive (encoding_selector, ANY_NO == any_reader_may_open (sysname));
 }
 
 GtkWidget *
@@ -805,9 +805,10 @@ psppire_window_open (PsppireWindow *de)
         gchar *encoding = psppire_encoding_selector_get_encoding (
           gtk_file_chooser_get_extra_widget (GTK_FILE_CHOOSER (dialog)));
 
-	if (any_reader_may_open (sysname))
+	enum detect_result res = any_reader_may_open (sysname);
+	if (ANY_YES == res)
           open_data_window (de, name, NULL);
-	else
+	else if (ANY_NO == res)
 	  open_syntax_window (name, encoding);
 
         g_free (encoding);
diff --git a/src/ui/gui/psppire.c b/src/ui/gui/psppire.c
index 7013fcfc1a..38845ed19f 100644
--- a/src/ui/gui/psppire.c
+++ b/src/ui/gui/psppire.c
@@ -105,11 +105,13 @@ initialize (const char *data_file)
     {
       gchar *filename = local_to_filename_encoding (data_file);
 
+      enum detect_result res = any_reader_may_open (filename);
+
       /* Check to see if the file is a .sav or a .por file.  If not
          assume that it is a syntax file */
-      if ( any_reader_may_open (filename))
-        open_data_window (NULL, filename, NULL);
-      else
+      if (res == ANY_YES)
+	open_data_window (NULL, filename, NULL);
+      else if (res == ANY_NO)
         {
           create_data_window ();
           open_syntax_window (filename, NULL);