1 /* Convert from memory to file representation. 2 Copyright (C) 1998, 1999, 2000, 2002 Red Hat, Inc. 3 Written by Ulrich Drepper <drepper@redhat.com>, 1998. 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation, version 2. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program; if not, write to the Free Software Foundation, 16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 17 18 #ifdef HAVE_CONFIG_H 19 # include <config.h> 20 #endif 21 22 #include <assert.h> 23 //#include <endian.h> 24 #include <string.h> 25 26 #include "libelfP.h" 27 28 #ifndef LIBELFBITS 29 # define LIBELFBITS 32 30 #endif 31 32 33 Elf_Data * 34 elfw2(LIBELFBITS, xlatetof) (dest, src, encode) 35 Elf_Data *dest; 36 const Elf_Data *src; 37 unsigned int encode; 38 { 39 /* First test whether the input data is really suitable for this 40 type. This means, whether there is an integer number of records. 41 Note that for this implementation the memory and file size of the 42 data types are identical. */ 43 #if EV_NUM != 2 44 size_t recsize = __libelf_type_sizes[src->d_version - 1][ELFW(ELFCLASS,LIBELFBITS) - 1][src->d_type]; 45 #else 46 size_t recsize = __libelf_type_sizes[0][ELFW(ELFCLASS,LIBELFBITS) - 1][src->d_type]; 47 #endif 48 49 if (src->d_size % recsize != 0) 50 { 51 __libelf_seterrno (ELF_E_INVALID_DATA); 52 return NULL; 53 } 54 55 /* Next see whether the converted data fits in the output buffer. */ 56 if (src->d_size > dest->d_size) 57 { 58 __libelf_seterrno (ELF_E_DEST_SIZE); 59 return NULL; 60 } 61 62 /* Test the encode parameter. */ 63 if (encode != ELFDATA2LSB && encode != ELFDATA2MSB) 64 { 65 __libelf_seterrno (ELF_E_INVALID_ENCODING); 66 return NULL; 67 } 68 69 /* Determine the translation function to use. 70 71 At this point we make an assumption which is valid for all 72 existing implementations so far: the memory and file sizes are 73 the same. This has very important consequences: 74 a) The requirement that the source and destination buffer can 75 overlap can easily be fulfilled. 76 b) We need only one function to convert from and memory to file 77 and vice versa since the function only has to copy and/or 78 change the byte order. 79 */ 80 if ((__BYTE_ORDER == __LITTLE_ENDIAN && encode == ELFDATA2LSB) 81 || (__BYTE_ORDER == __BIG_ENDIAN && encode == ELFDATA2MSB)) 82 { 83 /* We simply have to copy since the byte order is the same. */ 84 if (src->d_buf != dest->d_buf) 85 memmove (dest->d_buf, src->d_buf, src->d_size); 86 } 87 else 88 { 89 xfct_t fctp; 90 91 /* Get a pointer to the transformation functions. The `#ifdef' is 92 a small optimization since we don't anticipate another ELF 93 version and so would waste "precious" code. */ 94 #if EV_NUM != 2 95 fctp = __elf_xfctstom[dest->d_version - 1][src->d_version - 1][ELFW(ELFCLASS, LIBELFBITS) - 1][src->d_type]; 96 #else 97 fctp = __elf_xfctstom[0][0][ELFW(ELFCLASS, LIBELFBITS) - 1][src->d_type]; 98 #endif 99 100 /* Do the real work. */ 101 (*fctp) (dest->d_buf, src->d_buf, src->d_size, 1); 102 } 103 104 /* Now set the real destination type and length since the operation was 105 successful. */ 106 dest->d_type = src->d_type; 107 dest->d_size = src->d_size; 108 109 return dest; 110 } 111 INTDEF(elfw2(LIBELFBITS, xlatetof)) 112