X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=dbus%2Fdbus-errors.c;h=a0571a50e07d5828e00350e2c23887a6f661deb1;hb=61d97215c317a4154df47fbfb882aab60b92fbab;hp=a469f7e63f725aeda21e29fe56b32301449067c3;hpb=6b40feaff4114ab3498ad06e13063fceff4d48e9;p=platform%2Fupstream%2Fdbus.git

diff --git a/dbus/dbus-errors.c b/dbus/dbus-errors.c
index a469f7e..a0571a5 100644
--- a/dbus/dbus-errors.c
+++ b/dbus/dbus-errors.c
@@ -1,10 +1,10 @@
-/* -*- mode: C; c-file-style: "gnu" -*- */
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
 /* dbus-errors.c Error reporting
  *
- * Copyright (C) 2002  Red Hat Inc.
+ * Copyright (C) 2002, 2004  Red Hat Inc.
  * Copyright (C) 2003  CodeFactory AB
  *
- * Licensed under the Academic Free License version 1.2
+ * Licensed under the Academic Free License version 2.1
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -18,45 +18,56 @@
  * 
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  *
  */
+
+#include <config.h>
 #include "dbus-errors.h"
 #include "dbus-internals.h"
+#include "dbus-string.h"
+#include "dbus-protocol.h"
 #include <stdarg.h>
-#include <stdio.h>
+#include <string.h>
 
 /**
- * @defgroup DBusErrors Error reporting
- * @ingroup  DBus
- * @brief Error reporting
- *
- * Types and functions related to reporting errors.
- *
+ * @defgroup DBusErrorInternals Error reporting internals
+ * @ingroup  DBusInternals
+ * @brief Error reporting internals
+ * @{
+ */
+
+/**
+ * @def DBUS_ERROR_INIT
  *
- * In essence D-BUS error reporting works as follows:
+ * Expands to a suitable initializer for a DBusError on the stack.
+ * Declaring a DBusError with:
  *
  * @code
- * DBusResultCode result = DBUS_RESULT_SUCCESS;
- * dbus_some_function (arg1, arg2, &result);
- * if (result != DBUS_RESULT_SUCCESS)
- *   printf ("an error occurred\n");
+ * DBusError error = DBUS_ERROR_INIT;
+ *
+ * do_things_with (&error);
  * @endcode
  *
- * @todo add docs with DBusError
+ * is a more concise form of:
  *
- * @todo add dbus_error_is_set() to check
- * whether an error is set.
- * 
- * @{
+ * @code
+ * DBusError error;
+ *
+ * dbus_error_init (&error);
+ * do_things_with (&error);
+ * @endcode
  */
 
+/**
+ * Internals of DBusError
+ */
 typedef struct
 {
-  const char *name; /**< error name */
+  char *name; /**< error name */
   char *message; /**< error message */
 
-  unsigned int const_message : 1; /** Message is not owned by DBusError */
+  unsigned int const_message : 1; /**< Message is not owned by DBusError */
 
   unsigned int dummy2 : 1; /**< placeholder */
   unsigned int dummy3 : 1; /**< placeholder */
@@ -67,82 +78,109 @@ typedef struct
   
 } DBusRealError;
 
+_DBUS_STATIC_ASSERT (sizeof (DBusRealError) == sizeof (DBusError));
+
 /**
- * Set a result code at a result code location,
- * if code_address is not #NULL.
+ * Returns a longer message describing an error name.
+ * If the error name is unknown, returns the name
+ * itself.
  *
- * @param code_address place to store the result code.
- * @param code the result code itself.
+ * @param error the error to describe
+ * @returns a constant string describing the error.
  */
-void
-dbus_set_result (DBusResultCode *code_address,
-                 DBusResultCode  code)
+static const char*
+message_from_error (const char *error)
 {
-  if (code_address)
-    *code_address = code;
+  if (strcmp (error, DBUS_ERROR_FAILED) == 0)
+    return "Unknown error";
+  else if (strcmp (error, DBUS_ERROR_NO_MEMORY) == 0)
+    return "Not enough memory available";
+  else if (strcmp (error, DBUS_ERROR_IO_ERROR) == 0)
+    return "Error reading or writing data";
+  else if (strcmp (error, DBUS_ERROR_BAD_ADDRESS) == 0)
+    return "Could not parse address";
+  else if (strcmp (error, DBUS_ERROR_NOT_SUPPORTED) == 0)
+    return "Feature not supported";
+  else if (strcmp (error, DBUS_ERROR_LIMITS_EXCEEDED) == 0)
+    return "Resource limits exceeded";
+  else if (strcmp (error, DBUS_ERROR_ACCESS_DENIED) == 0)
+    return "Permission denied";
+  else if (strcmp (error, DBUS_ERROR_AUTH_FAILED) == 0)
+    return "Could not authenticate to server";
+  else if (strcmp (error, DBUS_ERROR_NO_SERVER) == 0)
+    return "No server available at address";
+  else if (strcmp (error, DBUS_ERROR_TIMEOUT) == 0)
+    return "Connection timed out";
+  else if (strcmp (error, DBUS_ERROR_NO_NETWORK) == 0)
+    return "Network unavailable";
+  else if (strcmp (error, DBUS_ERROR_ADDRESS_IN_USE) == 0)
+    return "Address already in use";
+  else if (strcmp (error, DBUS_ERROR_DISCONNECTED) == 0)
+    return "Disconnected.";
+  else if (strcmp (error, DBUS_ERROR_INVALID_ARGS) == 0)
+    return "Invalid arguments.";
+  else if (strcmp (error, DBUS_ERROR_NO_REPLY) == 0)
+    return "Did not get a reply message.";
+  else if (strcmp (error, DBUS_ERROR_FILE_NOT_FOUND) == 0)
+    return "File doesn't exist.";
+  else if (strcmp (error, DBUS_ERROR_OBJECT_PATH_IN_USE) == 0)
+    return "Object path already in use";
+  else
+    return error;
 }
 
+/** @} */ /* End of internals */
+
 /**
- * Returns a string describing the given result code.
+ * @defgroup DBusErrors Error reporting
+ * @ingroup  DBus
+ * @brief Error reporting
  *
- * @param code the result code to describe.
- * @returns a constant string describing the code.
+ * Types and functions related to reporting errors.
+ *
+ *
+ * In essence D-Bus error reporting works as follows:
+ *
+ * @code
+ * DBusError error;
+ * dbus_error_init (&error);
+ * dbus_some_function (arg1, arg2, &error);
+ * if (dbus_error_is_set (&error))
+ *   {
+ *     fprintf (stderr, "an error occurred: %s\n", error.message);
+ *     dbus_error_free (&error);
+ *   }
+ * @endcode
+ *
+ * By convention, all functions allow #NULL instead of a DBusError*,
+ * so callers who don't care about the error can ignore it.
+ * 
+ * There are some rules. An error passed to a D-Bus function must
+ * always be unset; you can't pass in an error that's already set.  If
+ * a function has a return code indicating whether an error occurred,
+ * and also a #DBusError parameter, then the error will always be set
+ * if and only if the return code indicates an error occurred. i.e.
+ * the return code and the error are never going to disagree.
+ *
+ * An error only needs to be freed if it's been set, not if
+ * it's merely been initialized.
+ *
+ * You can check the specific error that occurred using
+ * dbus_error_has_name().
+ * 
+ * Errors will not be set for programming errors, such as passing
+ * invalid arguments to the libdbus API. Instead, libdbus will print
+ * warnings, exit on a failed assertion, or even crash in those cases
+ * (in other words, incorrect use of the API results in undefined
+ * behavior, possibly accompanied by helpful debugging output if
+ * you're lucky).
+ * 
+ * @{
  */
-const char*
-dbus_result_to_string (DBusResultCode code)
-{
-  /* This is a switch to the compiler will complain if we
-   * aren't handling some codes
-   */
-  switch (code)
-    {
-    case DBUS_RESULT_SUCCESS:
-      return "Success";
-    case DBUS_RESULT_FAILED:
-      return "Unknown error";
-    case DBUS_RESULT_NO_MEMORY:
-      return "Not enough memory available";
-    case DBUS_RESULT_IO_ERROR:
-      return "Error reading or writing data";
-    case DBUS_RESULT_BAD_ADDRESS:
-      return "Could not parse address";
-    case DBUS_RESULT_NOT_SUPPORTED:
-      return "Feature not supported";
-    case DBUS_RESULT_LIMITS_EXCEEDED:
-      return "Resource limits exceeded";
-    case DBUS_RESULT_ACCESS_DENIED:
-      return "Permission denied";
-    case DBUS_RESULT_AUTH_FAILED:
-      return "Could not authenticate to server";
-    case DBUS_RESULT_NO_SERVER:
-      return "No server";
-    case DBUS_RESULT_TIMEOUT:
-      return "Connection timed out";
-    case DBUS_RESULT_NO_NETWORK:
-      return "Network unavailable";
-    case DBUS_RESULT_ADDRESS_IN_USE:
-      return "Address already in use";
-    case DBUS_RESULT_DISCONNECTED:
-      return "Disconnected.";
-    case DBUS_RESULT_INVALID_ARGS:
-      return "Invalid argumemts.";
-    case DBUS_RESULT_NO_REPLY:
-      return "Did not get a reply message.";
-    case DBUS_RESULT_FILE_NOT_FOUND:
-      return "File doesn't exist.";
-      
-      /* no default, it would break our compiler warnings */
-    }
-
-  return "Invalid error code";
-}
 
 /**
- * Initializes a DBusError structure.
- * 
- * @todo calling dbus_error_init() in here is no good,
- * for the same reason a GError* has to be set to NULL
- * before you pass it in.
+ * Initializes a DBusError structure. Does not allocate any memory;
+ * the error only needs to be freed if it is set at some point.
  *
  * @param error the DBusError.
  */
@@ -151,7 +189,7 @@ dbus_error_init (DBusError *error)
 {
   DBusRealError *real;
 
-  _dbus_assert (error != NULL);
+  _dbus_return_if_fail (error != NULL);
 
   _dbus_assert (sizeof (DBusError) == sizeof (DBusRealError));
 
@@ -164,7 +202,8 @@ dbus_error_init (DBusError *error)
 }
 
 /**
- * Frees an error created by dbus_error_init().
+ * Frees an error that's been set (or just initialized),
+ * then reinitializes the error as in dbus_error_init().
  *
  * @param error memory where the error is stored.
  */
@@ -173,17 +212,30 @@ dbus_error_free (DBusError *error)
 {
   DBusRealError *real;
 
+  _dbus_return_if_fail (error != NULL);
+  
   real = (DBusRealError *)error;
 
   if (!real->const_message)
-    dbus_free (real->message);
+    {
+      dbus_free (real->name);
+      dbus_free (real->message);
+    }
+
+  dbus_error_init (error);
 }
 
 /**
- * Assigns an error name and message to a DBusError.
- * Does nothing if error is #NULL.
+ * Assigns an error name and message to a DBusError.  Does nothing if
+ * error is #NULL. The message may be #NULL, which means a default
+ * message will be deduced from the name. The default message will be
+ * totally useless, though, so using a #NULL message is not recommended.
  *
- * @param error the error.
+ * Because this function does not copy the error name or message, you
+ * must ensure the name and message are global data that won't be
+ * freed. You probably want dbus_set_error() instead, in most cases.
+ * 
+ * @param error the error or #NULL
  * @param name the error name (not copied!!!)
  * @param message the error message (not copied!!!)
  */
@@ -194,28 +246,108 @@ dbus_set_error_const (DBusError  *error,
 {
   DBusRealError *real;
 
+  _dbus_return_if_error_is_set (error);
+  _dbus_return_if_fail (name != NULL);
+  
   if (error == NULL)
     return;
+
+  _dbus_assert (error->name == NULL);
+  _dbus_assert (error->message == NULL);
+
+  if (message == NULL)
+    message = message_from_error (name);
   
   real = (DBusRealError *)error;
   
-  real->name = name;
+  real->name = (char*) name;
   real->message = (char *)message;
   real->const_message = TRUE;
 }
 
 /**
+ * Moves an error src into dest, freeing src and
+ * overwriting dest. Both src and dest must be initialized.
+ * src is reinitialized to an empty error. dest may not
+ * contain an existing error. If the destination is
+ * #NULL, just frees and reinits the source error.
+ * 
+ * @param src the source error
+ * @param dest the destination error or #NULL
+ */
+void
+dbus_move_error (DBusError *src,
+                 DBusError *dest)
+{
+  _dbus_return_if_error_is_set (dest);
+
+  if (dest)
+    {
+      dbus_error_free (dest);
+      *dest = *src;
+      dbus_error_init (src);
+    }
+  else
+    dbus_error_free (src);
+}
+
+/**
+ * Checks whether the error is set and has the given
+ * name.
+ * @param error the error
+ * @param name the name
+ * @returns #TRUE if the given named error occurred
+ */
+dbus_bool_t
+dbus_error_has_name (const DBusError *error,
+                     const char      *name)
+{
+  _dbus_return_val_if_fail (error != NULL, FALSE);
+  _dbus_return_val_if_fail (name != NULL, FALSE);
+
+  _dbus_assert ((error->name != NULL && error->message != NULL) ||
+                (error->name == NULL && error->message == NULL));
+  
+  if (error->name != NULL)
+    {
+      DBusString str1, str2;
+      _dbus_string_init_const (&str1, error->name);
+      _dbus_string_init_const (&str2, name);
+      return _dbus_string_equal (&str1, &str2);
+    }
+  else
+    return FALSE;
+}
+
+/**
+ * Checks whether an error occurred (the error is set).
+ *
+ * @param error the error object
+ * @returns #TRUE if an error occurred
+ */
+dbus_bool_t
+dbus_error_is_set (const DBusError *error)
+{
+  _dbus_return_val_if_fail (error != NULL, FALSE);  
+  _dbus_assert ((error->name != NULL && error->message != NULL) ||
+                (error->name == NULL && error->message == NULL));
+  return error->name != NULL;
+}
+
+/**
  * Assigns an error name and message to a DBusError.
  * Does nothing if error is #NULL.
  *
+ * The format may be #NULL, which means a (pretty much useless)
+ * default message will be deduced from the name. This is not a good
+ * idea, just go ahead and provide a useful error message. It won't
+ * hurt you.
+ *
  * If no memory can be allocated for the error message, 
  * an out-of-memory error message will be set instead.
  *
- * @todo stdio.h shouldn't be included in this file,
- * should write _dbus_string_append_printf instead
- * 
- * @param error the error.
- * @param name the error name (not copied!!!)
+ * @param error the error.or #NULL
+ * @param name the error name
  * @param format printf-style format string.
  */
 void
@@ -225,37 +357,65 @@ dbus_set_error (DBusError  *error,
 		...)
 {
   DBusRealError *real;
-  va_list args, args2;
-  int message_length;
-  char *message;
-  char c;
-
+  DBusString str;
+  va_list args;
+  
   if (error == NULL)
     return;
+
+  /* it's a bug to pile up errors */
+  _dbus_return_if_error_is_set (error);
+  _dbus_return_if_fail (name != NULL);
   
-  va_start (args, format);
-  /* Measure the message length */
-  message_length = vsnprintf (&c, 1, format, args) + 1;
-  va_end (args);
-  
-  message = dbus_malloc (message_length);
+  _dbus_assert (error->name == NULL);
+  _dbus_assert (error->message == NULL);
+
+  if (!_dbus_string_init (&str))
+    goto nomem;
   
-  if (!message)
+  if (format == NULL)
     {
-      dbus_set_error_const (error, DBUS_ERROR_NO_MEMORY,
-			    "Failed to allocate memory for error message.");
-      return;
+      if (!_dbus_string_append (&str,
+                                message_from_error (name)))
+        {
+          _dbus_string_free (&str);
+          goto nomem;
+        }
+    }
+  else
+    {
+      va_start (args, format);
+      if (!_dbus_string_append_printf_valist (&str, format, args))
+        {
+          _dbus_string_free (&str);
+          va_end (args);
+          goto nomem;
+        }
+      va_end (args);
     }
-  
-  va_start (args, format);  
-  vsprintf (message, format, args2);  
-  va_end (args);
 
   real = (DBusRealError *)error;
+
+  if (!_dbus_string_steal_data (&str, &real->message))
+    {
+      _dbus_string_free (&str);
+      goto nomem;
+    }
+  _dbus_string_free (&str);
   
-  real->name = name;
-  real->message = message;
+  real->name = _dbus_strdup (name);
+  if (real->name == NULL)
+    {
+      dbus_free (real->message);
+      real->message = NULL;
+      goto nomem;
+    }
   real->const_message = FALSE;
+
+  return;
+  
+ nomem:
+  _DBUS_SET_OOM (error);
 }
 
-/** @} */
+/** @} */ /* End public API */