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1 /* Test program for elf_update function.
2    Copyright (C) 2000, 2002 Red Hat, Inc.
3    Written by Ulrich Drepper <drepper@redhat.com>, 2000.
4 
5    This program is Open Source software; you can redistribute it and/or
6    modify it under the terms of the Open Software License version 1.0 as
7    published by the Open Source Initiative.
8 
9    You should have received a copy of the Open Software License along
10    with this program; if not, you may obtain a copy of the Open Software
11    License version 1.0 from http://www.opensource.org/licenses/osl.php or
12    by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
13    3001 King Ranch Road, Ukiah, CA 95482.   */
14 
15 #ifdef HAVE_CONFIG_H
16 # include <config.h>
17 #endif
18 
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <libelf.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 
26 
27 int
main(int argc,char * argv[])28 main (int argc, char *argv[])
29 {
30   const char *fname = "xxx";
31   int fd;
32   Elf *elf;
33   Elf32_Ehdr *ehdr;
34   Elf32_Phdr *phdr;
35   int i;
36 
37   fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, 0666);
38   if (fd == -1)
39     {
40       printf ("cannot open `%s': %s\n", fname, strerror (errno));
41       exit (1);
42     }
43 
44   elf_version (EV_CURRENT);
45 
46   elf = elf_begin (fd, ELF_C_WRITE, NULL);
47   if (elf == NULL)
48     {
49       printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
50       exit (1);
51     }
52 
53   /* Create an ELF header.  */
54   ehdr = elf32_newehdr (elf);
55   if (ehdr == NULL)
56     {
57       printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
58       exit (1);
59     }
60 
61   /* Print the ELF header values.  */
62   if (argc > 1)
63     {
64       for (i = 0; i < EI_NIDENT; ++i)
65 	printf (" %02x", ehdr->e_ident[i]);
66       printf ("\
67 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
68 	      "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
69 	      "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
70 	      ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
71 	      ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
72 	      ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
73 	      ehdr->e_shnum, ehdr->e_shstrndx);
74     }
75 
76   ehdr->e_ident[0] = 42;
77   ehdr->e_ident[4] = 1;
78   ehdr->e_ident[5] = 1;
79   ehdr->e_ident[6] = 2;
80   ehdr->e_type = ET_EXEC;
81   ehdr->e_version = 1;
82   ehdr->e_ehsize = 1;
83   elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
84 
85   /* Create the program header.  */
86   phdr = elf32_newphdr (elf, 1);
87   if (phdr == NULL)
88     {
89       printf ("cannot create program header: %s\n", elf_errmsg (-1));
90       exit (1);
91     }
92 
93   phdr[0].p_type = PT_PHDR;
94   elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
95 
96   /* Let the library compute the internal structure information.  */
97   if (elf_update (elf, ELF_C_NULL) < 0)
98     {
99       printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
100       exit (1);
101     }
102 
103   ehdr = elf32_getehdr (elf);
104 
105   phdr[0].p_offset = ehdr->e_phoff;
106   phdr[0].p_offset = ehdr->e_phoff;
107   phdr[0].p_vaddr = ehdr->e_phoff;
108   phdr[0].p_paddr = ehdr->e_phoff;
109   phdr[0].p_flags = PF_R | PF_X;
110   phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
111   phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
112   phdr[0].p_align = sizeof (Elf32_Word);
113 
114   /* Write out the file.  */
115   if (elf_update (elf, ELF_C_WRITE) < 0)
116     {
117       printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
118       exit (1);
119     }
120 
121   /* Print the ELF header values.  */
122   if (argc > 1)
123     {
124       for (i = 0; i < EI_NIDENT; ++i)
125 	printf (" %02x", ehdr->e_ident[i]);
126       printf ("\
127 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
128 	      "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
129 	      "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
130 	      ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
131 	      ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
132 	      ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
133 	      ehdr->e_shnum, ehdr->e_shstrndx);
134     }
135 
136   if (elf_end (elf) != 0)
137     {
138       printf ("failure in elf_end: %s\n", elf_errmsg (-1));
139       exit (1);
140     }
141 
142   return 0;
143 }
144