json-gvariant: Stop string to GVariant conversion failing due to unrelated errno changes

This was observed as failing due to some codepath inside g_variant_new_string
setting errno to EAGAIN. Json Glib was erroneously detecting this in the checks
designed to catch string to integer conversions.

Solved by making errno only checked after the integer conversions.

1 files changed, 33 insertions, 11 deletions

diff --git a/json-glib/json-gvariant.c b/json-glib/json-gvariant.c
index 8185cac..72df81d 100644
--- a/json-glib/json-gvariant.c
+++ b/json-glib/json-gvariant.c
@@ -840,6 +840,10 @@ gvariant_simple_from_string (const gchar    *st,
 {
   GVariant *variant = NULL;
   gchar *nptr = NULL;
+  gboolean conversion_error = FALSE;
+  gint64 signed_value;
+  guint64 unsigned_value;
+  gdouble double_value;
 
   errno = 0;
 
@@ -851,43 +855,61 @@ gvariant_simple_from_string (const gchar    *st,
       else if (g_strcmp0 (st, "false") == 0)
         variant = g_variant_new_boolean (FALSE);
       else
-        errno = 1;
+        conversion_error = TRUE;
       break;
 
     case G_VARIANT_CLASS_BYTE:
-      variant = g_variant_new_byte (g_ascii_strtoll (st, &nptr, 10));
+      signed_value = g_ascii_strtoll (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_byte (signed_value);
       break;
 
     case G_VARIANT_CLASS_INT16:
-      variant = g_variant_new_int16 (g_ascii_strtoll (st, &nptr, 10));
+      signed_value = g_ascii_strtoll (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_int16 (signed_value);
       break;
 
     case G_VARIANT_CLASS_UINT16:
-      variant = g_variant_new_uint16 (g_ascii_strtoll (st, &nptr, 10));
+      signed_value = g_ascii_strtoll (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_uint16 (signed_value);
       break;
 
     case G_VARIANT_CLASS_INT32:
-      variant = g_variant_new_int32 (g_ascii_strtoll (st, &nptr, 10));
+      signed_value = g_ascii_strtoll (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_int32 (signed_value);
       break;
 
     case G_VARIANT_CLASS_UINT32:
-      variant = g_variant_new_uint32 (g_ascii_strtoull (st, &nptr, 10));
+      unsigned_value = g_ascii_strtoull (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_uint32 (unsigned_value);
       break;
 
     case G_VARIANT_CLASS_INT64:
-      variant = g_variant_new_int64 (g_ascii_strtoll (st, &nptr, 10));
+      signed_value = g_ascii_strtoll (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_int64 (signed_value);
       break;
 
     case G_VARIANT_CLASS_UINT64:
-      variant = g_variant_new_uint64 (g_ascii_strtoull (st, &nptr, 10));
+      unsigned_value = g_ascii_strtoull (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_uint64 (unsigned_value);
       break;
 
     case G_VARIANT_CLASS_HANDLE:
-      variant = g_variant_new_handle (strtol (st, &nptr, 10));
+      signed_value = strtol (st, &nptr, 10);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_handle (signed_value);
       break;
 
     case G_VARIANT_CLASS_DOUBLE:
-      variant = g_variant_new_double (g_ascii_strtod (st, &nptr));
+      double_value = g_ascii_strtod (st, &nptr);
+      conversion_error = errno != 0 || nptr == st;
+      variant = g_variant_new_double (double_value);
       break;
 
     case G_VARIANT_CLASS_STRING:
@@ -901,7 +923,7 @@ gvariant_simple_from_string (const gchar    *st,
       break;
     }
 
-  if (errno != 0 || nptr == st)
+  if (conversion_error)
     {
       g_set_error_literal (error,
                            G_IO_ERROR,