xref: /freebsd/sys/sys/exec.h (revision d5bc81e6c76ba6fcf4c7a813e3b9731a7889d64e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef _SYS_EXEC_H_
38 #define _SYS_EXEC_H_
39 
40 /*
41  * Before ps_args existed, the following structure, found at the top of
42  * the user stack of each user process, was used by ps(1) to locate
43  * environment and argv strings.  Normally ps_argvstr points to the
44  * argv vector, and ps_nargvstr is the same as the program's argc. The
45  * fields ps_envstr and ps_nenvstr are the equivalent for the environment.
46  *
47  * Programs should now use setproctitle(3) to change ps output.
48  * setproctitle() always informs the kernel with sysctl and sets the
49  * pointers in ps_strings.  The kern.proc.args sysctl first tries p_args.
50  * If p_args is NULL, it then falls back to reading ps_strings and following
51  * the pointers.
52  */
53 struct ps_strings {
54 	char	**ps_argvstr;	/* first of 0 or more argument strings */
55 	unsigned int ps_nargvstr; /* the number of argument strings */
56 	char	**ps_envstr;	/* first of 0 or more environment strings */
57 	unsigned int ps_nenvstr; /* the number of environment strings */
58 };
59 
60 struct image_params;
61 
62 struct execsw {
63 	int (*ex_imgact)(struct image_params *);
64 	const char *ex_name;
65 };
66 
67 #include <machine/exec.h>
68 
69 #ifdef _KERNEL
70 #include <sys/cdefs.h>
71 
72 /*
73  * Address of ps_strings structure (in user space).
74  * Prefer the kern.ps_strings or kern.proc.ps_strings sysctls to this constant.
75  */
76 #define	PS_STRINGS	(USRSTACK - sizeof(struct ps_strings))
77 #define	PROC_PS_STRINGS(p)	\
78 	((p)->p_vmspace->vm_stacktop - (p)->p_sysent->sv_psstringssz)
79 
80 /*
81  * Address of signal trampoline (in user space).
82  * This assumes that the sigcode resides in the shared page.
83  */
84 #define PROC_SIGCODE(p)		\
85 	((p)->p_vmspace->vm_shp_base + (p)->p_sysent->sv_sigcode_offset)
86 
87 #define PROC_HAS_SHP(p)		\
88 	((p)->p_sysent->sv_shared_page_obj != NULL)
89 
90 int exec_map_first_page(struct image_params *);
91 void exec_unmap_first_page(struct image_params *);
92 
93 int exec_register(const struct execsw *);
94 int exec_unregister(const struct execsw *);
95 
96 enum uio_seg;
97 
98 /*
99  * note: name##_mod cannot be const storage because the
100  * linker_file_sysinit() function modifies _file in the
101  * moduledata_t.
102  */
103 
104 #include <sys/module.h>
105 
106 #define EXEC_SET(name, execsw_arg) \
107 	static int __CONCAT(name,_modevent)(module_t mod, int type, \
108 	    void *data) \
109 	{ \
110 		struct execsw *exec = (struct execsw *)data; \
111 		int error = 0; \
112 		switch (type) { \
113 		case MOD_LOAD: \
114 			/* printf(#name " module loaded\n"); */ \
115 			error = exec_register(exec); \
116 			if (error) \
117 				printf(__XSTRING(name) "register failed\n"); \
118 			break; \
119 		case MOD_UNLOAD: \
120 			/* printf(#name " module unloaded\n"); */ \
121 			error = exec_unregister(exec); \
122 			if (error) \
123 				printf(__XSTRING(name) " unregister failed\n");\
124 			break; \
125 		default: \
126 			error = EOPNOTSUPP; \
127 			break; \
128 		} \
129 		return error; \
130 	} \
131 	static moduledata_t __CONCAT(name,_mod) = { \
132 		__XSTRING(name), \
133 		__CONCAT(name,_modevent), \
134 		(void *)& execsw_arg \
135 	}; \
136 	DECLARE_MODULE_TIED(name, __CONCAT(name,_mod), SI_SUB_EXEC, \
137 	    SI_ORDER_ANY)
138 #endif
139 
140 #endif
141