1/*
2 * Copyright (c) 1999-2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23/*
24** This file contains interfaces to the symbols defined int the crt modules.
25** 3 April 1995
26** Matt Watson (mwatson@next.com)
27**
28*/
29
30#if defined(__DYNAMIC__)
31#include "mach-o/dyld.h" /* defines _dyld_lookup_and_bind() */
32#define DECLARE_VAR(var, type)					\
33        static type * var ## _pointer = 0
34#define DECLARE_PROGNAME(var, type)				\
35        static type * var ## _pointer = 0;			\
36        static type _priv_ ## var = 0
37#define USE_VAR(var) (var ## _pointer)
38#else
39#define DECLARE_VAR(var, type) extern type var
40#define DECLARE_PROGNAME(var, type) DECLARE_VAR(var, type)
41#define USE_VAR(var) (& var)
42#endif
43
44DECLARE_VAR(NXArgv, char **);
45DECLARE_VAR(NXArgc, int);
46DECLARE_VAR(environ, char **);
47DECLARE_VAR(_mh_execute_header, struct mach_header);
48DECLARE_PROGNAME(__progname, char *);
49
50char ***_NSGetArgv(void) {
51    return(USE_VAR(NXArgv));
52}
53
54int *_NSGetArgc(void) {
55    return(USE_VAR(NXArgc));
56}
57
58char ***_NSGetEnviron(void) {
59    return(USE_VAR(environ));
60}
61
62char **_NSGetProgname(void) {
63    return(USE_VAR(__progname));
64}
65
66struct mach_header *_NSGetMachExecuteHeader(void) {
67    return(USE_VAR(_mh_execute_header));
68}
69
70#if __DYNAMIC__
71struct ProgramVars
72{
73    void*	mh;
74    int*	NXArgcPtr;
75    char***	NXArgvPtr;
76    char***	environPtr;
77    char**	__prognamePtr;
78};
79
80
81#define SUPPORT_PRE_GM_10_5_EXECUTABLES (__ppc__ || __i386__)
82
83
84/*
85 * dyld calls libSystem_initializer() and passes it a ProgramVars struct containing pointers to the
86 * main executable's NXArg* global variables. libSystem_initializer() calls __libc_init() which calls
87 * _program_vars_init() passing the ProgramVars parameter.
88 */
89void __attribute__((visibility("hidden")))
90_program_vars_init(const struct ProgramVars* vars) {
91#if SUPPORT_PRE_GM_10_5_EXECUTABLES
92    // to support transitional 10.5 main executables that don't have extended __dyld section and instead call _NSSetProgramVars,
93    // don't overwrite values set by _NSSetProgramVars()
94    if ( NXArgv_pointer != NULL )
95	return;
96#endif
97    NXArgv_pointer		= vars->NXArgvPtr;
98    NXArgc_pointer		= vars->NXArgcPtr;
99    environ_pointer		= vars->environPtr;
100    __progname_pointer		= vars->__prognamePtr;
101    _mh_execute_header_pointer	= vars->mh;
102}
103
104#if SUPPORT_PRE_GM_10_5_EXECUTABLES
105/*
106 * This is only called by main executables built with pre 10-5 GM crt1.10.5.o.  In those programs,
107 * there is no extended __dyld section, dyld cannot tell _program_vars_init() where the real program
108 * variables are, so they get temp values and are set for real here.
109 */
110void _NSSetProgramVars(int* crt_argc, char*** crt_argv, char*** crt_environ, struct mach_header* crt_mh, char** crt_progname) {
111    NXArgv_pointer		= crt_argv;
112    NXArgc_pointer		= crt_argc;
113    environ_pointer		= crt_environ;
114    __progname_pointer		= crt_progname;
115    _mh_execute_header_pointer	= crt_mh;
116}
117#endif
118#endif /* __DYNAMIC__ */
119
120#if __ppc__
121/*
122 * Fix for Radar bug 2200596 --
123 * EH symbol definitions for gcc 2.7.2.x implementation of
124 * C++ exception handling.  The problem:  the EH implementation
125 * has "throw" store stuff into these pointers, and then as the
126 * stack is unwound, the code generated into each function (for
127 * checking whether this function contains a relevant "catch"
128 * clause and for calling destructors for local variables) looks
129 * at these globals to find the type and value thrown.
130 *
131 * The problem was that the compiler generated the symbols as
132 * "common" symbols, and common symbols cannot be placed in
133 * dynamic shared libraries.  So we must put these guys as
134 * "data" symbols into crt0.o or the System Framework (library),
135 * and the compiler must generate code that defines the symbols
136 * as external references instead of common.
137 *
138 * I changed the symbol names (added the "_272") to be utterly
139 * paranoid about any possible future use of similar names by
140 * any future versions of gcc.
141 *                      -- D. Landauer, Jan. 1998
142 */
143
144void *__eh_pc_gcc_272 = (void *)0;
145void *__eh_type_gcc_272 = (void *)0;
146void *__eh_value_gcc_272 = (void *)0;
147
148/* This is what egcs uses for its global data pointer */
149void *__eh_global_dataptr = (void *)0;
150#endif /* __ppc__ */
151
152