1 // Copyright 2012 Google Inc. 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are 6 // met: 7 // 8 // * Redistributions of source code must retain the above copyright 9 // notice, this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above copyright 11 // notice, this list of conditions and the following disclaimer in the 12 // documentation and/or other materials provided with the distribution. 13 // * Neither the name of Google Inc. nor the names of its contributors 14 // may be used to endorse or promote products derived from this software 15 // without specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29 /// \file error.h 30 /// High-level representation of error conditions. 31 /// 32 /// The error module provides a mechanism to represent error conditions in an 33 /// efficient manner. In the case of a successful operation, an error is 34 /// internally represented as a NULL pointer and thus has no overhead. In the 35 /// case of an actual error, the representation is more complex and costly than 36 /// a traditional libc error number, but is also more verbose. Because errors 37 /// are not (or should not be!) in the critical path, this is not a concern. 38 39 #if !defined(KYUA_ERROR_H) 40 #define KYUA_ERROR_H 41 42 #include "error_fwd.h" 43 44 #include <stdbool.h> 45 #include <stddef.h> 46 #include <stdio.h> 47 48 #include "defs.h" 49 50 51 /// Type of the per-error formatting function. 52 /// 53 /// These functions take three arguments: the error to be formatted, a pointer 54 /// to the output buffer and the size of the output buffer. The return value 55 /// indicates how many bytes were written to the output buffer, or a negative 56 /// value in case of an error. 57 typedef int (*kyua_error_format_callback)( 58 struct kyua_error* const, char* const, const size_t); 59 60 61 /// Representation of an error. 62 struct kyua_error { 63 /// Whether the error object has to be released or not. 64 /// 65 /// Sometimes (the oom error), a kyua_error_t object may point to a 66 /// statically allocated error. Such object cannot be freed. 67 bool needs_free; 68 69 /// Name of the type. 70 const char* type_name; 71 72 /// Opaquet error-specific data. 73 void* data; 74 75 /// Method to generate a textual representation of the error. 76 kyua_error_format_callback format_callback; 77 }; 78 79 80 kyua_error_t kyua_error_new(const char*, void*, size_t, 81 kyua_error_format_callback); 82 void kyua_error_free(kyua_error_t); 83 kyua_error_t kyua_error_subsume(kyua_error_t, kyua_error_t); 84 85 kyua_error_t kyua_error_ok(void); 86 bool kyua_error_is_set(const kyua_error_t); 87 bool kyua_error_is_type(const kyua_error_t, const char*); 88 89 const void* kyua_error_data(const kyua_error_t); 90 int kyua_error_format(const kyua_error_t, char* const, size_t); 91 void kyua_error_err(const int, const kyua_error_t, const char*, ...) 92 KYUA_DEFS_NORETURN KYUA_DEFS_FORMAT_PRINTF(3, 4); 93 void kyua_error_fprintf(FILE*, const kyua_error_t, const char*, ...); 94 void kyua_error_warn(const kyua_error_t, const char*, ...); 95 96 97 extern const char* const kyua_generic_error_type; 98 kyua_error_t kyua_generic_error_new(const char* , ...) 99 KYUA_DEFS_FORMAT_PRINTF(1, 2); 100 101 102 extern const char* const kyua_libc_error_type; 103 kyua_error_t kyua_libc_error_new(int, const char* , ...) 104 KYUA_DEFS_FORMAT_PRINTF(2, 3); 105 int kyua_libc_error_errno(const kyua_error_t); 106 107 108 extern const char* const kyua_oom_error_type; 109 kyua_error_t kyua_oom_error_new(void); 110 111 112 extern const char* const kyua_usage_error_type; 113 kyua_error_t kyua_usage_error_new(const char* , ...) 114 KYUA_DEFS_FORMAT_PRINTF(1, 2); 115 116 117 #endif // !defined(KYUA_ERROR_H) 118