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/* Copyright (C) 1985, 1986, 1987, 1988, 1990, 1992
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Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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In other words, you are welcome to use, share and improve this program.
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You are forbidden to forbid anyone else to use, share and improve
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what you give them. Help stamp out software-hoarding! */
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* unexec.c - Convert a running program into an a.out file.
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* Author: Spencer W. Thomas
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* Computer Science Dept.
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* Date: Tue Mar 2 1982
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* Modified heavily since then.
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* unexec (new_name, a_name, data_start, bss_start, entry_address)
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* char *new_name, *a_name;
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* unsigned data_start, bss_start, entry_address;
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* Takes a snapshot of the program and makes an a.out format file in the
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* file named by the string argument new_name.
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* If a_name is non-NULL, the symbol table will be taken from the given file.
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* On some machines, an existing a_name file is required.
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* The boundaries within the a.out file may be adjusted with the data_start
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* and bss_start arguments. Either or both may be given as 0 for defaults.
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* Data_start gives the boundary between the text segment and the data
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* segment of the program. The text segment can contain shared, read-only
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* program code and literal data, while the data segment is always unshared
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* and unprotected. Data_start gives the lowest unprotected address.
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* The value you specify may be rounded down to a suitable boundary
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* as required by the machine you are using.
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* Specifying zero for data_start means the boundary between text and data
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* should not be the same as when the program was loaded.
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* If NO_REMAP is defined, the argument data_start is ignored and the
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* segment boundaries are never changed.
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* Bss_start indicates how much of the data segment is to be saved in the
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* a.out file and restored when the program is executed. It gives the lowest
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* unsaved address, and is rounded up to a page boundary. The default when 0
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* is given assumes that the entire data segment is to be stored, including
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* the previous data and bss as well as any additional storage allocated with
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* The new file is set up to start at entry_address.
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* If you make improvements I'd like to get them too.
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* harpo!utah-cs!thomas, thomas@Utah-20
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/* Even more heavily modified by james@bigtex.cactus.org of Dell Computer Co.
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* Basic theory: the data space of the running process needs to be
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* dumped to the output file. Normally we would just enlarge the size
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* of .data, scooting everything down. But we can't do that in ELF,
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* because there is often something between the .data space and the
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* In the temacs dump below, notice that the Global Offset Table
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* (.got) and the Dynamic link data (.dynamic) come between .data1 and
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* .bss. It does not work to overlap .data with these fields.
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* The solution is to create a new .data segment. This segment is
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* filled with data from the current process. Since the contents of
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* various sections refer to sections by index, the new .data segment
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* is made the last in the table to avoid changing any existing index.
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* This is an example of how the section headers are changed. "Addr"
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* is a process virtual address. "Offset" is a file offset.
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raid:/nfs/raid/src/dist-18.56/src> dump -h temacs
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**** SECTION HEADER TABLE ****
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[No] Type Flags Addr Offset Size Name
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Link Info Adralgn Entsize
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[1] 1 2 0x80480d4 0xd4 0x13 .interp
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[2] 5 2 0x80480e8 0xe8 0x388 .hash
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[3] 11 2 0x8048470 0x470 0x7f0 .dynsym
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[4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
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[5] 9 2 0x8049010 0x1010 0x338 .rel.plt
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[6] 1 6 0x8049348 0x1348 0x3 .init
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[7] 1 6 0x804934c 0x134c 0x680 .plt
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[8] 1 6 0x80499cc 0x19cc 0x3c56f .text
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[9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
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[10] 1 2 0x8085f40 0x3df40 0x69c .rodata
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[11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
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[12] 1 3 0x8088330 0x3f330 0x20afc .data
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[13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
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[14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
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[15] 6 3 0x80a9874 0x60874 0x80 .dynamic
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[16] 8 3 0x80a98f4 0x608f4 0x449c .bss
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[17] 2 0 0 0x608f4 0x9b90 .symtab
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[18] 3 0 0 0x6a484 0x8526 .strtab
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[19] 3 0 0 0x729aa 0x93 .shstrtab
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[20] 1 0 0 0x72a3d 0x68b7 .comment
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raid:/nfs/raid/src/dist-18.56/src> dump -h xemacs
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**** SECTION HEADER TABLE ****
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[No] Type Flags Addr Offset Size Name
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Link Info Adralgn Entsize
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[1] 1 2 0x80480d4 0xd4 0x13 .interp
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[2] 5 2 0x80480e8 0xe8 0x388 .hash
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[3] 11 2 0x8048470 0x470 0x7f0 .dynsym
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[4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
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[5] 9 2 0x8049010 0x1010 0x338 .rel.plt
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[6] 1 6 0x8049348 0x1348 0x3 .init
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[7] 1 6 0x804934c 0x134c 0x680 .plt
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[8] 1 6 0x80499cc 0x19cc 0x3c56f .text
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[9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
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[10] 1 2 0x8085f40 0x3df40 0x69c .rodata
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[11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
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[12] 1 3 0x8088330 0x3f330 0x20afc .data
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[13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
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[14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
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[15] 6 3 0x80a9874 0x60874 0x80 .dynamic
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[16] 8 3 0x80c6800 0x7d800 0 .bss
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[17] 2 0 0 0x7d800 0x9b90 .symtab
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[18] 3 0 0 0x87390 0x8526 .strtab
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[19] 3 0 0 0x8f8b6 0x93 .shstrtab
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[20] 1 0 0 0x8f949 0x68b7 .comment
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[21] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
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* This is an example of how the file header is changed. "Shoff" is
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* the section header offset within the file. Since that table is
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* after the new .data section, it is moved. "Shnum" is the number of
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* sections, which we increment.
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* "Phoff" is the file offset to the program header. "Phentsize" and
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* "Shentsz" are the program and section header entries sizes respectively.
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* These can be larger than the apparent struct sizes.
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raid:/nfs/raid/src/dist-18.56/src> dump -f temacs
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Class Data Type Machine Version
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Entry Phoff Shoff Flags Ehsize
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Phentsize Phnum Shentsz Shnum Shstrndx
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0x80499cc 0x34 0x792f4 0 0x34
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raid:/nfs/raid/src/dist-18.56/src> dump -f xemacs
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Class Data Type Machine Version
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Entry Phoff Shoff Flags Ehsize
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Phentsize Phnum Shentsz Shnum Shstrndx
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0x80499cc 0x34 0x96200 0 0x34
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* These are the program headers. "Offset" is the file offset to the
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* segment. "Vaddr" is the memory load address. "Filesz" is the
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* segment size as it appears in the file, and "Memsz" is the size in
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* memory. Below, the third segment is the code and the fourth is the
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* data: the difference between Filesz and Memsz is .bss
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raid:/nfs/raid/src/dist-18.56/src> dump -o temacs
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***** PROGRAM EXECUTION HEADER *****
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Type Offset Vaddr Paddr
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Filesz Memsz Flags Align
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0x3f2f9 0x3f2f9 5 0x1000
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1 0x3f330 0x8088330 0
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0x215c4 0x25a60 7 0x1000
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2 0x60874 0x80a9874 0
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raid:/nfs/raid/src/dist-18.56/src> dump -o xemacs
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***** PROGRAM EXECUTION HEADER *****
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Type Offset Vaddr Paddr
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Filesz Memsz Flags Align
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0x3f2f9 0x3f2f9 5 0x1000
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1 0x3f330 0x8088330 0
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0x3e4d0 0x3e4d0 7 0x1000
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2 0x60874 0x80a9874 0
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/* Modified by wtien@urbana.mcd.mot.com of Motorola Inc.
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* The above mechanism does not work if the unexeced ELF file is being
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* re-layout by other applications (such as `strip'). All the applications
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* that re-layout the internal of ELF will layout all sections in ascending
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* order of their file offsets. After the re-layout, the data2 section will
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* still be the LAST section in the section header vector, but its file offset
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* is now being pushed far away down, and causes part of it not to be mapped
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* in (ie. not covered by the load segment entry in PHDR vector), therefore
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* causes the new binary to fail.
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* The solution is to modify the unexec algorithm to insert the new data2
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* section header right before the new bss section header, so their file
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* offsets will be in the ascending order. Since some of the section's (all
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* sections AFTER the bss section) indexes are now changed, we also need to
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* modify some fields to make them point to the right sections. This is done
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* by macro PATCH_INDEX. All the fields that need to be patched are:
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* 1. ELF header e_shstrndx field.
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* 2. section header sh_link and sh_info field.
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* 3. symbol table entry st_shndx field.
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* The above example now should look like:
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**** SECTION HEADER TABLE ****
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[No] Type Flags Addr Offset Size Name
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Link Info Adralgn Entsize
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[1] 1 2 0x80480d4 0xd4 0x13 .interp
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[2] 5 2 0x80480e8 0xe8 0x388 .hash
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[3] 11 2 0x8048470 0x470 0x7f0 .dynsym
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[4] 3 2 0x8048c60 0xc60 0x3ad .dynstr
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[5] 9 2 0x8049010 0x1010 0x338 .rel.plt
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[6] 1 6 0x8049348 0x1348 0x3 .init
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[7] 1 6 0x804934c 0x134c 0x680 .plt
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[8] 1 6 0x80499cc 0x19cc 0x3c56f .text
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[9] 1 6 0x8085f3c 0x3df3c 0x3 .fini
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[10] 1 2 0x8085f40 0x3df40 0x69c .rodata
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[11] 1 2 0x80865dc 0x3e5dc 0xd51 .rodata1
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[12] 1 3 0x8088330 0x3f330 0x20afc .data
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[13] 1 3 0x80a8e2c 0x5fe2c 0x89d .data1
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[14] 1 3 0x80a96cc 0x606cc 0x1a8 .got
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[15] 6 3 0x80a9874 0x60874 0x80 .dynamic
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[16] 1 3 0x80a98f4 0x608f4 0x1cf0c .data
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[17] 8 3 0x80c6800 0x7d800 0 .bss
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[18] 2 0 0 0x7d800 0x9b90 .symtab
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[19] 3 0 0 0x87390 0x8526 .strtab
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[20] 3 0 0 0x8f8b6 0x93 .shstrtab
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[21] 1 0 0 0x8f949 0x68b7 .comment
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <syms.h> /* for HDRR declaration */
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#include <sys/mman.h>
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#define fatal(a, b, c) fprintf(stderr, a, b, c), exit(1)
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/* Get the address of a particular section or program header entry,
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* accounting for the size of the entries.
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#define OLD_SECTION_H(n) \
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(*(Elf32_Shdr *) ((byte *) old_section_h + old_file_h->e_shentsize * (n)))
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#define NEW_SECTION_H(n) \
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(*(Elf32_Shdr *) ((byte *) new_section_h + new_file_h->e_shentsize * (n)))
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#define OLD_PROGRAM_H(n) \
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(*(Elf32_Phdr *) ((byte *) old_program_h + old_file_h->e_phentsize * (n)))
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#define NEW_PROGRAM_H(n) \
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(*(Elf32_Phdr *) ((byte *) new_program_h + new_file_h->e_phentsize * (n)))
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#define PATCH_INDEX(n) \
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if ((n) >= old_bss_index) \
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typedef unsigned char byte;
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/* Round X up to a multiple of Y. */
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/* ****************************************************************
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* In ELF, this works by replacing the old .bss section with a new
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* .data section, and inserting an empty .bss immediately afterwards.
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unexec (new_name, old_name, data_start, bss_start, entry_address)
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char *new_name, *old_name;
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unsigned data_start, bss_start, entry_address;
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/* extern unsigned int bss_end; */
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int new_file, old_file, new_file_size;
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/* Pointers to the base of the image of the two files. */
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caddr_t old_base, new_base;
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/* Pointers to the file, program and section headers for the old and new
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Elf32_Ehdr *old_file_h, *new_file_h;
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Elf32_Phdr *old_program_h, *new_program_h;
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Elf32_Shdr *old_section_h, *new_section_h;
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/* Point to the section name table in the old file. */
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char *old_section_names;
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Elf32_Addr old_bss_addr, new_bss_addr;
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Elf32_Word old_bss_size, new_data2_size;
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Elf32_Off new_data2_offset;
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Elf32_Addr new_data2_addr;
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int n, nn, old_bss_index, old_data_index, new_data2_index;
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int old_mdebug_index;
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struct stat stat_buf;
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/* Open the old file & map it into the address space. */
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old_file = open (old_name, O_RDONLY);
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fatal ("Can't open %s for reading: errno %d\n", old_name, errno);
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if (fstat (old_file, &stat_buf) == -1)
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fatal ("Can't fstat(%s): errno %d\n", old_name, errno);
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old_base = mmap (0, stat_buf.st_size, PROT_READ, MAP_SHARED, old_file, 0);
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if (old_base == (caddr_t) -1)
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fatal ("Can't mmap(%s): errno %d\n", old_name, errno);
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fprintf (stderr, "mmap(%s, %x) -> %x\n", old_name, stat_buf.st_size,
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/* Get pointers to headers & section names. */
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old_file_h = (Elf32_Ehdr *) old_base;
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old_program_h = (Elf32_Phdr *) ((byte *) old_base + old_file_h->e_phoff);
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old_section_h = (Elf32_Shdr *) ((byte *) old_base + old_file_h->e_shoff);
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= (char *) old_base + OLD_SECTION_H (old_file_h->e_shstrndx).sh_offset;
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/* Find the mdebug section, if any. */
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for (old_mdebug_index = 1; old_mdebug_index < old_file_h->e_shnum; old_mdebug_index++)
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fprintf (stderr, "Looking for .mdebug - found %s\n",
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old_section_names + OLD_SECTION_H(old_mdebug_index).sh_name);
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if (!strcmp (old_section_names + OLD_SECTION_H(old_mdebug_index).sh_name,
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if (old_mdebug_index == old_file_h->e_shnum)
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old_mdebug_index = -1; /* just means no such section was present */
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/* Find the old .bss section. Figure out parameters of the new
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data2 and bss sections. */
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for (old_bss_index = 1; old_bss_index < old_file_h->e_shnum; old_bss_index++)
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fprintf (stderr, "Looking for .bss - found %s\n",
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old_section_names + OLD_SECTION_H(old_bss_index).sh_name);
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if (!strcmp (old_section_names + OLD_SECTION_H(old_bss_index).sh_name,
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if (old_bss_index == old_file_h->e_shnum)
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fatal ("Can't find .bss in %s.\n", old_name, 0);
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old_bss_addr = OLD_SECTION_H (old_bss_index).sh_addr;
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old_bss_size = OLD_SECTION_H (old_bss_index).sh_size;
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#if defined(emacs) || !defined(DEBUG)
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bss_end = (unsigned int) sbrk (0);
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new_bss_addr = (Elf32_Addr) bss_end;
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new_bss_addr = old_bss_addr + old_bss_size + 0x1234;
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new_data2_addr = old_bss_addr;
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new_data2_size = new_bss_addr - old_bss_addr;
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new_data2_offset = OLD_SECTION_H (old_bss_index).sh_offset;
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fprintf (stderr, "old_bss_index %d\n", old_bss_index);
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fprintf (stderr, "old_bss_addr %x\n", old_bss_addr);
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fprintf (stderr, "old_bss_size %x\n", old_bss_size);
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fprintf (stderr, "new_bss_addr %x\n", new_bss_addr);
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fprintf (stderr, "new_data2_addr %x\n", new_data2_addr);
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fprintf (stderr, "new_data2_size %x\n", new_data2_size);
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fprintf (stderr, "new_data2_offset %x\n", new_data2_offset);
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if ((unsigned) new_bss_addr < (unsigned) old_bss_addr + old_bss_size)
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fatal (".bss shrank when undumping???\n", 0, 0);
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/* Set the output file to the right size and mmap it. Set
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pointers to various interesting objects. stat_buf still has
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new_file = open (new_name, O_RDWR | O_CREAT, 0666);
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fatal ("Can't creat (%s): errno %d\n", new_name, errno);
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new_file_size = stat_buf.st_size + old_file_h->e_shentsize + new_data2_size;
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if (ftruncate (new_file, new_file_size))
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fatal ("Can't ftruncate (%s): errno %d\n", new_name, errno);
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new_base = mmap (0, new_file_size, PROT_READ | PROT_WRITE, MAP_SHARED,
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if (new_base == (caddr_t) -1)
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fatal ("Can't mmap (%s): errno %d\n", new_name, errno);
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new_file_h = (Elf32_Ehdr *) new_base;
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new_program_h = (Elf32_Phdr *) ((byte *) new_base + old_file_h->e_phoff);
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= (Elf32_Shdr *) ((byte *) new_base + old_file_h->e_shoff
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/* Make our new file, program and section headers as copies of the
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memcpy (new_file_h, old_file_h, old_file_h->e_ehsize);
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memcpy (new_program_h, old_program_h,
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old_file_h->e_phnum * old_file_h->e_phentsize);
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/* Modify the e_shstrndx if necessary. */
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PATCH_INDEX (new_file_h->e_shstrndx);
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/* Fix up file header. We'll add one section. Section header is
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new_file_h->e_shoff += new_data2_size;
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new_file_h->e_shnum += 1;
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fprintf (stderr, "Old section offset %x\n", old_file_h->e_shoff);
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fprintf (stderr, "Old section count %d\n", old_file_h->e_shnum);
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fprintf (stderr, "New section offset %x\n", new_file_h->e_shoff);
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fprintf (stderr, "New section count %d\n", new_file_h->e_shnum);
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/* Fix up a new program header. Extend the writable data segment so
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that the bss area is covered too. Find that segment by looking
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for a segment that ends just before the .bss area. Make sure
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that no segments are above the new .data2. Put a loop at the end
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to adjust the offset and address of any segment that is above
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data2, just in case we decide to allow this later. */
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for (n = new_file_h->e_phnum - 1; n >= 0; n--)
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/* Compute maximum of all requirements for alignment of section. */
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int alignment = (NEW_PROGRAM_H (n)).p_align;
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if ((OLD_SECTION_H (old_bss_index)).sh_addralign > alignment)
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alignment = OLD_SECTION_H (old_bss_index).sh_addralign;
645
/* Supposedly this condition is okay for the SGI. */
647
if (NEW_PROGRAM_H (n).p_vaddr + NEW_PROGRAM_H (n).p_filesz > old_bss_addr)
648
fatal ("Program segment above .bss in %s\n", old_name, 0);
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if (NEW_PROGRAM_H (n).p_type == PT_LOAD
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&& (round_up ((NEW_PROGRAM_H (n)).p_vaddr
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+ (NEW_PROGRAM_H (n)).p_filesz,
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== round_up (old_bss_addr, alignment)))
659
fatal ("Couldn't find segment next to .bss in %s\n", old_name, 0);
661
NEW_PROGRAM_H (n).p_filesz += new_data2_size;
662
NEW_PROGRAM_H (n).p_memsz = NEW_PROGRAM_H (n).p_filesz;
664
#if 1 /* Maybe allow section after data2 - does this ever happen? */
665
for (n = new_file_h->e_phnum - 1; n >= 0; n--)
667
if (NEW_PROGRAM_H (n).p_vaddr
668
&& NEW_PROGRAM_H (n).p_vaddr >= new_data2_addr)
669
NEW_PROGRAM_H (n).p_vaddr += new_data2_size - old_bss_size;
671
if (NEW_PROGRAM_H (n).p_offset >= new_data2_offset)
672
NEW_PROGRAM_H (n).p_offset += new_data2_size;
676
/* Fix up section headers based on new .data2 section. Any section
677
whose offset or virtual address is after the new .data2 section
678
gets its value adjusted. .bss size becomes zero and new address
679
is set. data2 section header gets added by copying the existing
680
.data header and modifying the offset, address and size. */
681
for (old_data_index = 1; old_data_index < old_file_h->e_shnum;
683
if (!strcmp (old_section_names + OLD_SECTION_H (old_data_index).sh_name,
686
if (old_data_index == old_file_h->e_shnum)
687
fatal ("Can't find .data in %s.\n", old_name, 0);
689
/* Walk through all section headers, insert the new data2 section right
690
before the new bss section. */
691
for (n = 1, nn = 1; n < old_file_h->e_shnum; n++, nn++)
694
/* If it is bss section, insert the new data2 section before it. */
695
if (n == old_bss_index)
697
/* Steal the data section header for this data2 section. */
698
memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (old_data_index),
699
new_file_h->e_shentsize);
701
NEW_SECTION_H (nn).sh_addr = new_data2_addr;
702
NEW_SECTION_H (nn).sh_offset = new_data2_offset;
703
NEW_SECTION_H (nn).sh_size = new_data2_size;
704
/* Use the bss section's alignment. This will assure that the
705
new data2 section always be placed in the same spot as the old
706
bss section by any other application. */
707
NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (n).sh_addralign;
709
/* Now copy over what we have in the memory now. */
710
memcpy (NEW_SECTION_H (nn).sh_offset + new_base,
711
(caddr_t) OLD_SECTION_H (n).sh_addr,
716
memcpy (&NEW_SECTION_H (nn), &OLD_SECTION_H (n),
717
old_file_h->e_shentsize);
719
/* The new bss section's size is zero, and its file offset and virtual
720
address should be off by NEW_DATA2_SIZE. */
721
if (n == old_bss_index)
723
/* NN should be `old_bss_index + 1' at this point. */
724
NEW_SECTION_H (nn).sh_offset += new_data2_size;
725
NEW_SECTION_H (nn).sh_addr += new_data2_size;
726
/* Let the new bss section address alignment be the same as the
727
section address alignment followed the old bss section, so
728
this section will be placed in exactly the same place. */
729
NEW_SECTION_H (nn).sh_addralign = OLD_SECTION_H (nn).sh_addralign;
730
NEW_SECTION_H (nn).sh_size = 0;
732
/* Any section that was original placed AFTER the bss section should now
733
be off by NEW_DATA2_SIZE. */
734
else if (NEW_SECTION_H (nn).sh_offset >= new_data2_offset)
735
NEW_SECTION_H (nn).sh_offset += new_data2_size;
737
/* If any section hdr refers to the section after the new .data
738
section, make it refer to next one because we have inserted
739
a new section in between. */
741
PATCH_INDEX (NEW_SECTION_H (nn).sh_link);
742
/* For symbol tables, info is a symbol table index,
743
so don't change it. */
744
if (NEW_SECTION_H (nn).sh_type != SHT_SYMTAB
745
&& NEW_SECTION_H (nn).sh_type != SHT_DYNSYM)
746
PATCH_INDEX (NEW_SECTION_H (nn).sh_info);
748
/* Now, start to copy the content of sections. */
749
if (NEW_SECTION_H (nn).sh_type == SHT_NULL
750
|| NEW_SECTION_H (nn).sh_type == SHT_NOBITS)
753
/* Write out the sections. .data and .data1 (and data2, called
754
".data" in the strings table) get copied from the current process
755
instead of the old file. */
756
if (!strcmp (old_section_names + NEW_SECTION_H (n).sh_name, ".data")
757
|| !strcmp ((old_section_names + NEW_SECTION_H (n).sh_name),
759
src = (caddr_t) OLD_SECTION_H (n).sh_addr;
761
src = old_base + OLD_SECTION_H (n).sh_offset;
763
memcpy (NEW_SECTION_H (nn).sh_offset + new_base, src,
764
NEW_SECTION_H (nn).sh_size);
766
/* Adjust the HDRR offsets in .mdebug and copy the
767
line data if it's in its usual 'hole' in the object.
768
Makes the new file debuggable with dbx.
769
patches up two problems: the absolute file offsets
770
in the HDRR record of .mdebug (see /usr/include/syms.h), and
771
the ld bug that gets the line table in a hole in the
772
elf file rather than in the .mdebug section proper.
773
David Anderson. davea@sgi.com Jan 16,1994. */
774
if (n == old_mdebug_index)
776
#define MDEBUGADJUST(__ct,__fileaddr) \
777
if (n_phdrr->__ct > 0) \
779
n_phdrr->__fileaddr += movement; \
782
HDRR * o_phdrr = (HDRR *)((byte *)old_base + OLD_SECTION_H (n).sh_offset);
783
HDRR * n_phdrr = (HDRR *)((byte *)new_base + NEW_SECTION_H (nn).sh_offset);
784
unsigned movement = new_data2_size;
786
MDEBUGADJUST (idnMax, cbDnOffset);
787
MDEBUGADJUST (ipdMax, cbPdOffset);
788
MDEBUGADJUST (isymMax, cbSymOffset);
789
MDEBUGADJUST (ioptMax, cbOptOffset);
790
MDEBUGADJUST (iauxMax, cbAuxOffset);
791
MDEBUGADJUST (issMax, cbSsOffset);
792
MDEBUGADJUST (issExtMax, cbSsExtOffset);
793
MDEBUGADJUST (ifdMax, cbFdOffset);
794
MDEBUGADJUST (crfd, cbRfdOffset);
795
MDEBUGADJUST (iextMax, cbExtOffset);
796
/* The Line Section, being possible off in a hole of the object,
797
requires special handling. */
798
if (n_phdrr->cbLine > 0)
800
if (o_phdrr->cbLineOffset > (OLD_SECTION_H (n).sh_offset
801
+ OLD_SECTION_H (n).sh_size))
803
/* line data is in a hole in elf. do special copy and adjust
806
n_phdrr->cbLineOffset += movement;
808
memcpy (n_phdrr->cbLineOffset + new_base,
809
o_phdrr->cbLineOffset + old_base, n_phdrr->cbLine);
813
/* somehow line data is in .mdebug as it is supposed to be. */
814
MDEBUGADJUST (cbLine, cbLineOffset);
819
/* If it is the symbol table, its st_shndx field needs to be patched. */
820
if (NEW_SECTION_H (nn).sh_type == SHT_SYMTAB
821
|| NEW_SECTION_H (nn).sh_type == SHT_DYNSYM)
823
Elf32_Shdr *spt = &NEW_SECTION_H (nn);
824
unsigned int num = spt->sh_size / spt->sh_entsize;
825
Elf32_Sym * sym = (Elf32_Sym *) (NEW_SECTION_H (nn).sh_offset
829
if (sym->st_shndx == SHN_UNDEF
830
|| sym->st_shndx == SHN_ABS
831
|| sym->st_shndx == SHN_COMMON)
834
PATCH_INDEX (sym->st_shndx);
839
/* Close the files and make the new file executable. */
841
if (close (old_file))
842
fatal ("Can't close (%s): errno %d\n", old_name, errno);
844
if (close (new_file))
845
fatal ("Can't close (%s): errno %d\n", new_name, errno);
847
if (stat (new_name, &stat_buf) == -1)
848
fatal ("Can't stat (%s): errno %d\n", new_name, errno);
852
stat_buf.st_mode |= 0111 & ~n;
853
if (chmod (new_name, stat_buf.st_mode) == -1)
854
fatal ("Can't chmod (%s): errno %d\n", new_name, errno);
added
removed
o/unexelfsgi.c
