error.h

   1 /*
   2  * QEMU Error Objects
   3  *
   4  * Copyright IBM, Corp. 2011
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU LGPL, version 2.  See
  10  * the COPYING.LIB file in the top-level directory.
  11  */
  12 #ifndef ERROR_H
  13 #define ERROR_H
  14
  15 #include "compiler.h"
  16 #include <stdbool.h>
  17
  18 /**
  19  * A class representing internal errors within QEMU.  An error has a string
  20  * typename and optionally a set of named string parameters.
  21  */
  22 typedef struct Error Error;
  23
  24 /**
  25  * Set an indirect pointer to an error given a printf-style format parameter.
  26  * Currently, qerror.h defines these error formats.  This function is not
  27  * meant to be used outside of QEMU.
  28  */
  29 void error_set(Error **err, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
  30
  31 /**
  32  * Returns true if an indirect pointer to an error is pointing to a valid
  33  * error object.
  34  */
  35 bool error_is_set(Error **err);
  36
  37 /**
  38  * Returns an exact copy of the error passed as an argument.
  39  */
  40 Error *error_copy(const Error *err);
  41
  42 /**
  43  * Get a human readable representation of an error object.
  44  */
  45 const char *error_get_pretty(Error *err);
  46
  47 /**
  48  * Get an individual named error field.
  49  */
  50 const char *error_get_field(Error *err, const char *field);
  51
  52 /**
  53  * Get an individual named error field.
  54  */
  55 void error_set_field(Error *err, const char *field, const char *value);
  56
  57 /**
  58  * Propagate an error to an indirect pointer to an error.  This function will
  59  * always transfer ownership of the error reference and handles the case where
  60  * dst_err is NULL correctly.  Errors after the first are discarded.
  61  */
  62 void error_propagate(Error **dst_err, Error *local_err);
  63
  64 /**
  65  * Free an error object.
  66  */
  67 void error_free(Error *err);
  68
  69 /**
  70  * Determine if an error is of a speific type (based on the qerror format).
  71  * Non-QEMU users should get the `class' field to identify the error type.
  72  */
  73 bool error_is_type(Error *err, const char *fmt);
  74
  75 #endif