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1 | /** @file\r | |
2 | This header, <stdarg.h>, declares type va_list and defines macros: va_start, va_arg, va_end;\r | |
3 | for advancing through a list of arguments whose number and types are not known to the\r | |
4 | called function when it is translated.\r | |
5 | \r | |
6 | A function may be called with a variable number of arguments of varying types.\r | |
7 | The rightmost argument plays a special role in the access mechanism, and will\r | |
8 | be designated paramN in this and subsequent descriptions.\r | |
9 | \r | |
10 | The type va_list is a type suitable for holding information needed by the\r | |
11 | macros va_start, va_arg, and va_end. If access to the varying arguments\r | |
12 | is desired, the called function shall declare an object (referred to as ap\r | |
13 | in these descriptions) having type va_list. The object ap may be passed as\r | |
14 | an argument to another function; if the receiving function invokes the va_arg macro\r | |
15 | with parameter ap, the value of ap in the calling function becomes indeterminate\r | |
16 | and must be passed to the va_end macro prior to any further reference to ap.\r | |
17 | \r | |
18 | The va_start and va_arg macros must be implemented as macros, not as actual\r | |
19 | functions. The va_start and va_end macros must be invoked in the\r | |
20 | function accepting a varying number of arguments, if access to the varying\r | |
21 | arguments is desired.\r | |
22 | \r | |
23 | Copyright (c) 2010 - 2012, Intel Corporation. All rights reserved.<BR>\r | |
24 | This program and the accompanying materials are licensed and made available under\r | |
25 | the terms and conditions of the BSD License that accompanies this distribution.\r | |
26 | The full text of the license may be found at\r | |
27 | http://opensource.org/licenses/bsd-license.\r | |
28 | \r | |
29 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
30 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
31 | **/\r | |
32 | #ifndef _STDARG_H\r | |
33 | #define _STDARG_H\r | |
34 | #include <sys/EfiCdefs.h>\r | |
35 | \r | |
36 | /** @{\r | |
37 | The type va_list is a type suitable for holding information needed by the\r | |
38 | macros va_start, va_arg, and va_end.\r | |
39 | \r | |
40 | Depending upon compiler or CPU architecture, different definitions are required.\r | |
41 | **/\r | |
42 | #if defined(__GNUC__)\r | |
43 | typedef __builtin_va_list va_list;\r | |
44 | #else\r | |
45 | #define va_list VA_LIST\r | |
46 | #endif\r | |
47 | /*@}*/\r | |
48 | \r | |
49 | /** @{\r | |
50 | The va_start macro must be invoked before any access to the unnamed arguments.\r | |
51 | The va_start macro initializes ap for subsequent use by va_arg and va_end.\r | |
52 | \r | |
53 | Synopsys: void va_start(va_list ap, paramN);\r | |
54 | \r | |
55 | @param ap An object of type va_list that is to be initialized such\r | |
56 | that subsequent successive invocations of va_arg will\r | |
57 | return the values of the parameters following paramN.\r | |
58 | \r | |
59 | @param paramN The parameter paramN is the identifier of the rightmost\r | |
60 | parameter in the variable parameter list in the function\r | |
61 | definition (the one just before the ,...). If the\r | |
62 | parameter parmN is declared with the register storage\r | |
63 | class, with a function of array type, or with a type that\r | |
64 | is not compatible with the type that results after\r | |
65 | application of the default argument promotions, the\r | |
66 | behavior is undefined.\r | |
67 | **/\r | |
68 | #if defined(__GNUC__)\r | |
69 | #define va_start __builtin_va_start\r | |
70 | #else\r | |
71 | #define va_start VA_START\r | |
72 | #endif\r | |
73 | /*@}*/\r | |
74 | \r | |
75 | /** @{\r | |
76 | The va_arg macro expands to an expression that has the type and value of\r | |
77 | the next argument in the call. The parameter ap shall be the same as the\r | |
78 | va_list ap initialized by va_start. Each invocation of va_arg modifies ap\r | |
79 | so that the values of successive arguments are returned in turn. The\r | |
80 | parameter type is a type name specified such that the type of a pointer to\r | |
81 | an object that has the specified type can be obtained simply by postfixing\r | |
82 | a * to type. If there is no actual next argument, or if type is not\r | |
83 | compatible with the type of the actual next argument (as promoted\r | |
84 | according to the default argument promotions), the behavior is undefined.\r | |
85 | \r | |
86 | Synopsys: type va_arg(va_list ap, type);\r | |
87 | \r | |
88 | @param ap An object of type va_list that was initialized by a prior\r | |
89 | invocation of va_start.\r | |
90 | \r | |
91 | @param type A type name specifying the type of the parameter to be retrieved.\r | |
92 | \r | |
93 | @return The first invocation of the va_arg macro after that of the\r | |
94 | va_start macro returns the value of the argument after that\r | |
95 | specified by paramN. Successive invocations return the values\r | |
96 | of the remaining arguments in succession.\r | |
97 | **/\r | |
98 | #if defined(__GNUC__)\r | |
99 | #define va_arg __builtin_va_arg\r | |
100 | #else\r | |
101 | #define va_arg VA_ARG\r | |
102 | #endif\r | |
103 | /*@}*/\r | |
104 | \r | |
105 | /** @{\r | |
106 | The va_end macro facillitates a normal return from the function whose\r | |
107 | variable argument list was referred to by the expansion of va_start that\r | |
108 | initialized the va_list ap.\r | |
109 | \r | |
110 | Synopsys: void va_end(va_list ap);\r | |
111 | \r | |
112 | The va_end macro may modify ap so that it is no longer usable (without an\r | |
113 | intervening invocation of va_start). If there is no corresponding\r | |
114 | invocation of the va_start macro, or if the va_end macro is not invoked\r | |
115 | before the return, the behavior is undefined.\r | |
116 | \r | |
117 | @param ap An object of type va_list, initialized by a prior\r | |
118 | invocation of va_start, that will no longer be referenced.\r | |
119 | **/\r | |
120 | #if defined(__GNUC__)\r | |
121 | #define va_end __builtin_va_end\r | |
122 | #else\r | |
123 | #define va_end VA_END\r | |
124 | #endif\r | |
125 | /*@}*/\r | |
126 | \r | |
127 | /** @{\r | |
128 | For BSD compatibility.\r | |
129 | **/\r | |
130 | #if defined(__GNUC__)\r | |
131 | #define va_copy __builtin_va_copy\r | |
132 | #else\r | |
133 | #define va_copy(s,d) (s) = (d)\r | |
134 | #endif\r | |
135 | /*@}*/\r | |
136 | \r | |
137 | /** Provide a generic version of the compiler-dependent __va_copy macro.\r | |
138 | Some software, such as Python 2.7.2, relies upon the existence of __va_copy.\r | |
139 | If this macro is not defined, it just assigns one va_list item to another.\r | |
140 | This breaks for compiler environments that define va_list as an array or structure.\r | |
141 | **/\r | |
142 | #ifndef __va_copy\r | |
143 | #define __va_copy va_copy\r | |
144 | #endif\r | |
145 | \r | |
146 | #endif /* _STDARG_H */\r |