glibc/elf/dl-load.c
Ulrich Drepper 4cca6b868f Update.
1997-03-08 05:30  Ulrich Drepper  <drepper@cygnus.com>

	* argp/Makefile (routines): Add argp-eexst.
	* argp/argp-ba.c (argp_program_bug_address): Make `const'.
	* argp/argp-eexst.c: New file.  Define exit status variable.
	* argp/argp-help.c (__argp_state_help): Use argp_err_exit_status
	variable instead of always exiting with value 1.
	* argp/argp-pv.c (argp_program_version): Make `const'.
	* argp/argp.h: Declare argp_err_exit_status.
	Patches by Miles Bader <miles@gnu.ai.mit.edu>.

	* locale/programs/localedef.c: Use argp_err_exit_status to
	terminate with correct value.

	* inet/rcmd.c (iruserok): Use euidaccess instead of half-hearted
	switching of UID before opening .rhosts.

	* libio/vsnprintf.c: Change implementation to follow ISO C 9X
	proposal.  The return value now is always the number of characters
	which would be written if enough space is available.
	* manual/stdio.texi: Update description for new behaviour.

	* locale/locale.h (__locale_t): Don't use __locale_t for struct
	name and pointer to struct since old gccs cannot keep the namespaces
	apart.  Rename struct to __locale_struct.
	* locale/duplocale.h: Likewise.
	* locale/newlocale.h: Likewise.

	* math/Makefile (headers): Add complex.h and cmathcalls.h.
	(routines): Remove w_cabs.  Add conj, cimag, creal, and cabs.
	* math/math.h: Undefine __MATHDECL_1, __MATHDECL, and __MATHCALL
	after use.
	(signgam): Move declaration to here from mathcalls.h.
	* math/mathcalls.h (cabs, __cabs_complex, signgam): Remove definition.
	Correct comment for fmin and fmax.
	Start implementing complex math function from ISO C 9X.
	* math/complex.h: New file.
	* math/cmathcalls.h: New file.
	* math/cabs.c: New file.
	* math/cabsf.c: New file.
	* math/cabsl.c: New file.
	* math/cimag.c: New file.
	* math/cimagf.c: New file.
	* math/cimagl.c: New file.
	* math/conj.c: New file.
	* math/conjf.c: New file.
	* math/conjl.c: New file.
	* math/creal.c: New file.
	* math/crealf.c: New file.
	* math/creall.c: New file.
	* sysdeps/libm-ieee754/w_cabs.c: Removed.
	* sysdeps/libm-ieee754/w_cabsf.c: Removed.
	* sysdeps/libm-ieee754/w_cabsl.c: Removed.

	* posix/regex.c: Merge with regex sources from Arnold Robbins'
	version in GNU awk.
	* posix/regex.h: Likewise.

	Add regex test suite by Tom Lord.
	* posix/Makefile (distribute): Add TESTS, TESTS2C.sed, and testcases.h.
	(tests): Add runtests.
	(before-compile): Add testcases.h.
	(testcases.h): New rule to generate header with tests.
	* posix/TESTS: New file.
	* posix/TESTS2C.sed.: New file.
	* posix/runtests.c: New file.
	* posix/testcases.h: New file.

	* sysdeps/unix/sysv/linux/poll.c: Test whether poll syscall is
	available and use fall-back implementation if not.

	* sysdeps/unix/sysv/linux/syscalls.list: Sort entries.

	* time/ialloc.c: Update from tzcode1997c.
	* time/private.h: Likewise.
	* time/scheck.c: Likewise.
	* time/tzselect.ksh: Likewise.
	* time/zdump.c: Likewise.
	* time/zic.c: Likewise.

	* time/tzfile.c: Pretty print.

1997-03-06 07:37  Geoff Keating  <geoffk@ozemail.com.au>

	Port to powerpc-*-linux-gnu.  Slightly tested, under MkLinux,
	on a 601.

	* sysdeps/powerpc/Implies: Added.
	* sysdeps/powerpc/__longjmp.S: Added.
	* sysdeps/powerpc/__math.h: Added.
	* sysdeps/powerpc/bsd-_setjmp.S: Added.
	* sysdeps/powerpc/bsd-setjmp.S: Added.
	* sysdeps/powerpc/dl-machine.h: Added.
	* sysdeps/powerpc/ffs.c: Added.
	* sysdeps/powerpc/fpu_control.h: Added.
	* sysdeps/powerpc/jmp_buf.h: Added.
	* sysdeps/powerpc/setjmp.S: Added.
	* sysdeps/powerpc/strlen.s: Added.
	* sysdeps/powerpc/elf/start.c: Added.
	* sysdeps/powerpc/fpu_control.h: Added.
	* sysdeps/powerpc/jmp_buf.h: Added.

	* sysdeps/unix/sysv/linux/powerpc/Dist: Added.
	* sysdeps/unix/sysv/linux/powerpc/_exit.S: Added.
	* sysdeps/unix/sysv/linux/powerpc/brk.c: Added.
	* sysdeps/unix/sysv/linux/powerpc/clone.S: Added.
	* sysdeps/unix/sysv/linux/powerpc/init-first.h: Added.
	* sysdeps/unix/sysv/linux/powerpc/ioctl-types.h: Added.
	* sysdeps/unix/sysv/linux/powerpc/profil.c: Added.
	* sysdeps/unix/sysv/linux/powerpc/sigreturn.S: Added.
	* sysdeps/unix/sysv/linux/powerpc/socket.S: Added.
	* sysdeps/unix/sysv/linux/powerpc/syscall.S: Added.
	* sysdeps/unix/sysv/linux/powerpc/syscalls.list: Added.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.c: Added.
	* sysdeps/unix/sysv/linux/powerpc/sysdep.h: Added.
	* sysdeps/unix/sysv/linux/powerpc/termbits.h: Added.
	* sysdeps/unix/sysv/linux/powerpc/sys/syscall.h: Added.

1997-03-05 05:24  Geoff Keating  <geoffk@ozemail.com.au>

	* elf/dl-runtime.c (fixup): Add ELF_FIXUP_RETURNS_ADDRESS switch,
	because knowing the first instruction of a PowerPC PLT trampoline
	is not very helpful.

1997-03-04 08:04  Geoff Keating  <geoffk@ozemail.com.au>

	* elf/dl-load.c (ELF_PREFERRED_ADDRESS, ELF_PREFERRED_ADDRESS_DATA,
	ELF_FIXED_ADDRESS): Added. These are for dl-machine.h to indicate
	a preference as to where executables should be loaded.

1997-02-28 08:50  Geoff Keating  <geoffk@ozemail.com.au>

	* elf/elf.h: Add in all those PowerPC reloc types.

1997-02-24 07:12  Geoff Keating  <geoffk@ozemail.com.au>

	* stdio-common/vfscanf.c: Use __va_copy if available.

1997-03-06 13:50  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* malloc/malloc.c (mprotect) [_LIBC]: Define as __mprotect to
	clean up namespace.

1997-03-07 14:27  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/libm-ieee754/s_fpclassify.c (__fpclassify): Don't use
	non-existing GET_WORDS macro, use EXTRACT_WORDS.
	Reported by Andres Schwab <schwab@issan.informatik.uni-dortmund.de>.

1997-03-07 05:27  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/unix/sysv/linux/i386/sigaction.c: The user- and
	kernel-level sigaction structure is different.  handle this
	correctly.
	Bug report by Andres Jaeger <jaeger@informatik.uni-kl.de>.

1997-03-06 05:55  David Engel  <david@sw.ods.com>

	* sysdeps/generic/dl-cache.c (_dl_load_cache_lookup): Also
	recognize cache entries with flag == 3.

1997-03-06 01:05  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/generic/netinet/in.h (INADDR_NONE): Cast to unsigned int.
	(INADDR_LOOPBACK): Likewise.
	* sysdeps/unix/sysv/linux/netinet/in.h: Likewise.

	* manual/socket.texi: Correct types of INADDR_* constants from
	unsigned long to unsigned.

1997-03-05 23:14  Ulrich Drepper  <drepper@cygnus.com>

	* time/antarctica: Update from tzdata1997c.
	* time/asia: Likewise.
	* time/zone.tab: Likewise.

1997-03-05 00:43  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* configure.in (libc_cv_asm_symver_directive,
	libc_cv_ld_version_script_option): Remove unknown instruction from
	assembler test file.

1997-03-04 19:14  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/fpu/__math.h: Update feature tests to use
	__USE_ISOC9X.
	[__USE_ISOC9X]: Define __log2 and __exp2 inlines.
	(fabs): Remove defininition, it is a gcc builtin.
	(sqrt, __sqrt): Remove definition, they have wrappers in libm.

1997-03-04 10:11  H.J. Lu  <hjl@lucon.org>

	* sunrpc/Makefile ($(objpfx)rpc-proto.c): Create subdir before
	generating file.

1997-03-05 03:59  Ulrich Drepper  <drepper@cygnus.com>

	* inet/rcmd.c (__ivaliduser): Don't use getline, but __getline
	instead to avoid namespace problems.
	Reported by David Mosberger-Tang <davidm@AZStarNet.COM>.

1997-03-03 19:01  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* login/utmp_file.c: Fix previous change.  Make portable by
	checking the _HAVE_UT_* feature macros.

	* libio/fileops.c (_IO_file_finish): Likewise.
1997-03-08 05:28:20 +00:00

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/* _dl_map_object -- Map in a shared object's segments from the file.
Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <link.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include "dynamic-link.h"
/* On some systems, no flag bits are given to specify file mapping. */
#ifndef MAP_FILE
#define MAP_FILE 0
#endif
/* The right way to map in the shared library files is MAP_COPY, which
makes a virtual copy of the data at the time of the mmap call; this
guarantees the mapped pages will be consistent even if the file is
overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we
get is MAP_PRIVATE, which copies each page when it is modified; this
means if the file is overwritten, we may at some point get some pages
from the new version after starting with pages from the old version. */
#ifndef MAP_COPY
#define MAP_COPY MAP_PRIVATE
#endif
#include <endian.h>
#if BYTE_ORDER == BIG_ENDIAN
#define byteorder ELFDATA2MSB
#define byteorder_name "big-endian"
#elif BYTE_ORDER == LITTLE_ENDIAN
#define byteorder ELFDATA2LSB
#define byteorder_name "little-endian"
#else
#error "Unknown BYTE_ORDER " BYTE_ORDER
#define byteorder ELFDATANONE
#endif
#define STRING(x) #x
#ifdef MAP_ANON
/* The fd is not examined when using MAP_ANON. */
#define ANONFD -1
#else
int _dl_zerofd = -1;
#define ANONFD _dl_zerofd
#endif
/* Handle situations where we have a preferred location in memory for
the shared objects. */
#ifdef ELF_PREFERRED_ADDRESS_DATA
ELF_PREFERRED_ADDRESS_DATA;
#endif
#ifndef ELF_PREFERRED_ADDRESS
#define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
#endif
#ifndef ELF_FIXED_ADDRESS
#define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
#endif
size_t _dl_pagesize;
/* Local version of `strdup' function. */
static inline char *
local_strdup (const char *s)
{
size_t len = strlen (s) + 1;
void *new = malloc (len);
if (new == NULL)
return NULL;
return (char *) memcpy (new, s, len);
}
/* Map in the shared object NAME, actually located in REALNAME, and already
opened on FD. */
struct link_map *
_dl_map_object_from_fd (char *name, int fd, char *realname,
struct link_map *loader, int l_type)
{
struct link_map *l = NULL;
void *file_mapping = NULL;
size_t mapping_size = 0;
#define LOSE(s) lose (0, (s))
void lose (int code, const char *msg)
{
(void) __close (fd);
if (file_mapping)
__munmap (file_mapping, mapping_size);
if (l)
{
/* Remove the stillborn object from the list and free it. */
if (l->l_prev)
l->l_prev->l_next = l->l_next;
if (l->l_next)
l->l_next->l_prev = l->l_prev;
free (l);
}
free (name);
free (realname);
_dl_signal_error (code, name, msg);
}
inline caddr_t map_segment (ElfW(Addr) mapstart, size_t len,
int prot, int fixed, off_t offset)
{
caddr_t mapat = __mmap ((caddr_t) mapstart, len, prot,
fixed|MAP_COPY|MAP_FILE,
fd, offset);
if (mapat == (caddr_t) -1)
lose (errno, "failed to map segment from shared object");
return mapat;
}
/* Make sure LOCATION is mapped in. */
void *map (off_t location, size_t size)
{
if ((off_t) mapping_size <= location + (off_t) size)
{
void *result;
if (file_mapping)
__munmap (file_mapping, mapping_size);
mapping_size = (location + size + 1 + _dl_pagesize - 1);
mapping_size &= ~(_dl_pagesize - 1);
result = __mmap (file_mapping, mapping_size, PROT_READ,
MAP_COPY|MAP_FILE, fd, 0);
if (result == (void *) -1)
lose (errno, "cannot map file data");
file_mapping = result;
}
return file_mapping + location;
}
const ElfW(Ehdr) *header;
const ElfW(Phdr) *phdr;
const ElfW(Phdr) *ph;
int type;
/* Look again to see if the real name matched another already loaded. */
for (l = _dl_loaded; l; l = l->l_next)
if (! strcmp (realname, l->l_name))
{
struct libname_list *lnp, *lastp;
/* The object is already loaded.
Just bump its reference count and return it. */
__close (fd);
/* If the name is not in the list of names for this object add
it. */
free (realname);
lastp = NULL;
for (lnp = l->l_libname; lnp != NULL; lastp = lnp, lnp = lnp->next)
if (strcmp (name, lnp->name) == 0)
{
free (name);
break;
}
if (lnp == NULL)
{
struct libname_list *newname = malloc (sizeof *newname);
if (newname == NULL)
/* No more memory. */
lose (ENOMEM, "cannot allocate name record");
/* The object should have a libname set. */
assert (lastp != NULL);
newname->name = name;
newname->next = NULL;
lastp->next = newname;
}
++l->l_opencount;
return l;
}
if (_dl_pagesize == 0)
_dl_pagesize = __getpagesize ();
/* Map in the first page to read the header. */
header = map (0, sizeof *header);
/* Check the header for basic validity. */
if (*(Elf32_Word *) &header->e_ident !=
#if BYTE_ORDER == LITTLE_ENDIAN
((ELFMAG0 << (EI_MAG0 * 8)) |
(ELFMAG1 << (EI_MAG1 * 8)) |
(ELFMAG2 << (EI_MAG2 * 8)) |
(ELFMAG3 << (EI_MAG3 * 8)))
#else
((ELFMAG0 << (EI_MAG3 * 8)) |
(ELFMAG1 << (EI_MAG2 * 8)) |
(ELFMAG2 << (EI_MAG1 * 8)) |
(ELFMAG3 << (EI_MAG0 * 8)))
#endif
)
LOSE ("invalid ELF header");
#define ELF32_CLASS ELFCLASS32
#define ELF64_CLASS ELFCLASS64
if (header->e_ident[EI_CLASS] != ELFW(CLASS))
LOSE ("ELF file class not " STRING(__ELF_WORDSIZE) "-bit");
if (header->e_ident[EI_DATA] != byteorder)
LOSE ("ELF file data encoding not " byteorder_name);
if (header->e_ident[EI_VERSION] != EV_CURRENT)
LOSE ("ELF file version ident not " STRING(EV_CURRENT));
if (header->e_version != EV_CURRENT)
LOSE ("ELF file version not " STRING(EV_CURRENT));
if (! elf_machine_matches_host (header->e_machine))
LOSE ("ELF file machine architecture not " ELF_MACHINE_NAME);
if (header->e_phentsize != sizeof (ElfW(Phdr)))
LOSE ("ELF file's phentsize not the expected size");
#ifndef MAP_ANON
#define MAP_ANON 0
if (_dl_zerofd == -1)
{
_dl_zerofd = _dl_sysdep_open_zero_fill ();
if (_dl_zerofd == -1)
{
__close (fd);
_dl_signal_error (errno, NULL, "cannot open zero fill device");
}
}
#endif
/* Enter the new object in the list of loaded objects. */
l = _dl_new_object (realname, name, l_type);
if (! l)
lose (ENOMEM, "cannot create shared object descriptor");
l->l_opencount = 1;
l->l_loader = loader;
/* Extract the remaining details we need from the ELF header
and then map in the program header table. */
l->l_entry = header->e_entry;
type = header->e_type;
l->l_phnum = header->e_phnum;
phdr = map (header->e_phoff, l->l_phnum * sizeof (ElfW(Phdr)));
{
/* Scan the program header table, collecting its load commands. */
struct loadcmd
{
ElfW(Addr) mapstart, mapend, dataend, allocend;
off_t mapoff;
int prot;
} loadcmds[l->l_phnum], *c;
size_t nloadcmds = 0;
l->l_ld = 0;
l->l_phdr = 0;
l->l_addr = 0;
for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
switch (ph->p_type)
{
/* These entries tell us where to find things once the file's
segments are mapped in. We record the addresses it says
verbatim, and later correct for the run-time load address. */
case PT_DYNAMIC:
l->l_ld = (void *) ph->p_vaddr;
break;
case PT_PHDR:
l->l_phdr = (void *) ph->p_vaddr;
break;
case PT_LOAD:
/* A load command tells us to map in part of the file.
We record the load commands and process them all later. */
if (ph->p_align % _dl_pagesize != 0)
LOSE ("ELF load command alignment not page-aligned");
if ((ph->p_vaddr - ph->p_offset) % ph->p_align)
LOSE ("ELF load command address/offset not properly aligned");
{
struct loadcmd *c = &loadcmds[nloadcmds++];
c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
c->mapend = ((ph->p_vaddr + ph->p_filesz + _dl_pagesize - 1)
& ~(_dl_pagesize - 1));
c->dataend = ph->p_vaddr + ph->p_filesz;
c->allocend = ph->p_vaddr + ph->p_memsz;
c->mapoff = ph->p_offset & ~(ph->p_align - 1);
c->prot = 0;
if (ph->p_flags & PF_R)
c->prot |= PROT_READ;
if (ph->p_flags & PF_W)
c->prot |= PROT_WRITE;
if (ph->p_flags & PF_X)
c->prot |= PROT_EXEC;
break;
}
}
/* We are done reading the file's headers now. Unmap them. */
__munmap (file_mapping, mapping_size);
/* Now process the load commands and map segments into memory. */
c = loadcmds;
if (type == ET_DYN || type == ET_REL)
{
/* This is a position-independent shared object. We can let the
kernel map it anywhere it likes, but we must have space for all
the segments in their specified positions relative to the first.
So we map the first segment without MAP_FIXED, but with its
extent increased to cover all the segments. Then we remove
access from excess portion, and there is known sufficient space
there to remap from the later segments.
As a refinement, sometimes we have an address that we would
prefer to map such objects at; but this is only a preference,
the OS can do whatever it likes. */
caddr_t mapat;
ElfW(Addr) mappref;
size_t maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
mappref = ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart);
mapat = map_segment (mappref, maplength, c->prot, 0, c->mapoff);
l->l_addr = (ElfW(Addr)) mapat - c->mapstart;
/* Change protection on the excess portion to disallow all access;
the portions we do not remap later will be inaccessible as if
unallocated. Then jump into the normal segment-mapping loop to
handle the portion of the segment past the end of the file
mapping. */
__mprotect ((caddr_t) (l->l_addr + c->mapend),
loadcmds[nloadcmds - 1].allocend - c->mapend,
0);
goto postmap;
}
else
{
/* Notify ELF_PREFERRED_ADDRESS that we have to load this one
fixed. */
ELF_FIXED_ADDRESS (loader, c->mapstart);
}
while (c < &loadcmds[nloadcmds])
{
if (c->mapend > c->mapstart)
/* Map the segment contents from the file. */
map_segment (l->l_addr + c->mapstart, c->mapend - c->mapstart,
c->prot, MAP_FIXED, c->mapoff);
postmap:
if (c->allocend > c->dataend)
{
/* Extra zero pages should appear at the end of this segment,
after the data mapped from the file. */
ElfW(Addr) zero, zeroend, zeropage;
zero = l->l_addr + c->dataend;
zeroend = l->l_addr + c->allocend;
zeropage = (zero + _dl_pagesize - 1) & ~(_dl_pagesize - 1);
if (zeroend < zeropage)
/* All the extra data is in the last page of the segment.
We can just zero it. */
zeropage = zeroend;
if (zeropage > zero)
{
/* Zero the final part of the last page of the segment. */
if ((c->prot & PROT_WRITE) == 0)
{
/* Dag nab it. */
if (__mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
_dl_pagesize, c->prot|PROT_WRITE) < 0)
lose (errno, "cannot change memory protections");
}
memset ((void *) zero, 0, zeropage - zero);
if ((c->prot & PROT_WRITE) == 0)
__mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
_dl_pagesize, c->prot);
}
if (zeroend > zeropage)
{
/* Map the remaining zero pages in from the zero fill FD. */
caddr_t mapat;
mapat = __mmap ((caddr_t) zeropage, zeroend - zeropage,
c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
ANONFD, 0);
if (mapat == (caddr_t) -1)
lose (errno, "cannot map zero-fill pages");
}
}
++c;
}
if (l->l_phdr == 0)
{
/* There was no PT_PHDR specified. We need to find the phdr in the
load image ourselves. We assume it is in fact in the load image
somewhere, and that the first load command starts at the
beginning of the file and thus contains the ELF file header. */
ElfW(Addr) bof = l->l_addr + loadcmds[0].mapstart;
assert (loadcmds[0].mapoff == 0);
l->l_phdr = (void *) (bof + ((const ElfW(Ehdr) *) bof)->e_phoff);
}
else
/* Adjust the PT_PHDR value by the runtime load address. */
(ElfW(Addr)) l->l_phdr += l->l_addr;
}
/* We are done mapping in the file. We no longer need the descriptor. */
__close (fd);
if (l->l_type == lt_library && type == ET_EXEC)
l->l_type = lt_executable;
if (l->l_ld == 0)
{
if (type == ET_DYN)
LOSE ("object file has no dynamic section");
}
else
(ElfW(Addr)) l->l_ld += l->l_addr;
l->l_entry += l->l_addr;
elf_get_dynamic_info (l->l_ld, l->l_info);
if (l->l_info[DT_HASH])
_dl_setup_hash (l);
return l;
}
/* Try to open NAME in one of the directories in DIRPATH.
Return the fd, or -1. If successful, fill in *REALNAME
with the malloc'd full directory name. */
static int
open_path (const char *name, size_t namelen,
const char *dirpath,
char **realname,
const char *trusted_dirs[])
{
char *buf;
const char *p;
int fd;
p = dirpath;
if (p == NULL || *p == '\0')
{
__set_errno (ENOENT);
return -1;
}
buf = __alloca (strlen (dirpath) + 1 + namelen);
do
{
size_t buflen;
size_t this_len;
dirpath = p;
p = strpbrk (dirpath, ":;");
if (p == NULL)
p = strchr (dirpath, '\0');
this_len = p - dirpath;
/* When we run a setuid program we do not accept any directory. */
if (__libc_enable_secure)
{
/* All trusted directory must be complete name. */
if (dirpath[0] != '/')
continue;
/* If we got a list of trusted directories only accept one
of these. */
if (trusted_dirs != NULL)
{
const char **trust = trusted_dirs;
while (*trust != NULL)
if (memcmp (dirpath, *trust, this_len) == 0
&& (*trust)[this_len] == '\0')
break;
else
++trust;
/* If directory is not trusted, ignore this directory. */
if (*trust == NULL)
continue;
}
}
if (this_len == 0)
{
/* Two adjacent colons, or a colon at the beginning or the end of
the path means to search the current directory. */
(void) memcpy (buf, name, namelen);
buflen = namelen;
}
else
{
/* Construct the pathname to try. */
(void) memcpy (buf, dirpath, this_len);
buf[this_len] = '/';
(void) memcpy (&buf[this_len + 1], name, namelen);
buflen = this_len + 1 + namelen;
}
fd = __open (buf, O_RDONLY);
if (fd != -1)
{
*realname = malloc (buflen);
if (*realname)
{
memcpy (*realname, buf, buflen);
return fd;
}
else
{
/* No memory for the name, we certainly won't be able
to load and link it. */
__close (fd);
return -1;
}
}
if (errno != ENOENT && errno != EACCES)
/* The file exists and is readable, but something went wrong. */
return -1;
}
while (*p++ != '\0');
return -1;
}
/* Map in the shared object file NAME. */
struct link_map *
_dl_map_object (struct link_map *loader, const char *name, int type,
int trace_mode)
{
int fd;
char *realname;
char *name_copy;
struct link_map *l;
/* Look for this name among those already loaded. */
for (l = _dl_loaded; l; l = l->l_next)
if (_dl_name_match_p (name, l) ||
/* If the requested name matches the soname of a loaded object,
use that object. */
(l->l_info[DT_SONAME] &&
! strcmp (name, (const char *) (l->l_addr +
l->l_info[DT_STRTAB]->d_un.d_ptr +
l->l_info[DT_SONAME]->d_un.d_val))))
{
/* The object is already loaded.
Just bump its reference count and return it. */
++l->l_opencount;
return l;
}
if (strchr (name, '/') == NULL)
{
/* Search for NAME in several places. */
size_t namelen = strlen (name) + 1;
inline void trypath (const char *dirpath, const char *trusted[])
{
fd = open_path (name, namelen, dirpath, &realname, trusted);
}
fd = -1;
/* First try the DT_RPATH of the dependent object that caused NAME
to be loaded. Then that object's dependent, and on up. */
for (l = loader; fd == -1 && l; l = l->l_loader)
if (l && l->l_info[DT_RPATH])
trypath ((const char *) (l->l_addr +
l->l_info[DT_STRTAB]->d_un.d_ptr +
l->l_info[DT_RPATH]->d_un.d_val), NULL);
/* If dynamically linked, try the DT_RPATH of the executable itself. */
l = _dl_loaded;
if (fd == -1 && l && l->l_type != lt_loaded && l->l_info[DT_RPATH])
trypath ((const char *) (l->l_addr +
l->l_info[DT_STRTAB]->d_un.d_ptr +
l->l_info[DT_RPATH]->d_un.d_val), NULL);
/* Try an environment variable (unless setuid). */
if (fd == -1)
{
static const char *trusted_dirs[] =
{
#include "trusted-dirs.h"
NULL
};
const char *ld_library_path = getenv ("LD_LIBRARY_PATH");
if (ld_library_path != NULL && *ld_library_path != '\0')
trypath (ld_library_path, trusted_dirs);
}
if (fd == -1)
{
/* Check the list of libraries in the file /etc/ld.so.cache,
for compatibility with Linux's ldconfig program. */
extern const char *_dl_load_cache_lookup (const char *name);
const char *cached = _dl_load_cache_lookup (name);
if (cached)
{
fd = __open (cached, O_RDONLY);
if (fd != -1)
{
realname = local_strdup (cached);
if (realname == NULL)
{
__close (fd);
fd = -1;
}
}
}
}
/* Finally, try the default path. */
if (fd == -1)
{
extern const char *_dl_rpath; /* Set in rtld.c. */
trypath (_dl_rpath, NULL);
}
}
else
{
fd = __open (name, O_RDONLY);
if (fd != -1)
{
realname = local_strdup (name);
if (realname == NULL)
{
__close (fd);
fd = -1;
}
}
}
if (fd != -1)
{
name_copy = local_strdup (name);
if (name_copy == NULL)
{
__close (fd);
fd = -1;
}
}
if (fd == -1)
{
if (trace_mode)
{
/* We haven't found an appropriate library. But since we
are only interested in the list of libraries this isn't
so severe. Fake an entry with all the information we
have. */
static const ElfW(Symndx) dummy_bucket = STN_UNDEF;
/* Enter the new object in the list of loaded objects. */
if ((name_copy = local_strdup (name)) == NULL
|| (l = _dl_new_object (name_copy, name, type)) == NULL)
_dl_signal_error (ENOMEM, name,
"cannot create shared object descriptor");
/* We use an opencount of 0 as a sign for the faked entry. */
l->l_opencount = 0;
l->l_reserved = 0;
l->l_buckets = &dummy_bucket;
l->l_nbuckets = 1;
l->l_relocated = 1;
return l;
}
else
_dl_signal_error (errno, name, "cannot open shared object file");
}
return _dl_map_object_from_fd (name_copy, fd, realname, loader, type);
}