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-rw-r--r--ChangeLog6
-rw-r--r--elf/dl-error.c10
-rw-r--r--elf/dl-fini.c2
-rw-r--r--elf/dl-init.c10
-rw-r--r--elf/dl-load.c21
-rw-r--r--elf/dl-lookup.c11
-rw-r--r--elf/dl-reloc.c2
-rw-r--r--elf/do-rel.h53
-rw-r--r--elf/dynamic-link.h12
-rw-r--r--elf/rtld.c9
-rw-r--r--sysdeps/i386/dl-machine.h43
-rw-r--r--sysdeps/i386/dl-runtime.c15
-rw-r--r--sysdeps/mach/hurd/dl-sysdep.c15
-rw-r--r--sysdeps/mach/hurd/i386/init-first.c71
14 files changed, 193 insertions, 87 deletions
diff --git a/ChangeLog b/ChangeLog
index 356fdf4..48af781 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue May 30 15:52:32 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
+
+ * mach/Makefile (server-interfaces): Removed notify and
+ device_reply. For shlibs with eager binding, libmachuser.so must
+ not refer to any functions not defined in libc.
+
Sat May 27 16:23:22 1995 Jim Meyering (meyering@comco.com)
* sysdeps/generic/memchr.c: Cast RHS to const unsigned char *
diff --git a/elf/dl-error.c b/elf/dl-error.c
index acb21a0..b5af2e3 100644
--- a/elf/dl-error.c
+++ b/elf/dl-error.c
@@ -43,8 +43,14 @@ _dl_catch_error (const char **errstring,
signalled_errstring = signalled_objname = NULL;
errcode = setjmp (catch_env);
- (*operate) ();
+ if (errcode == 0)
+ {
+ (*operate) ();
+ return 0;
+ }
+
+ /* We get here only if we longjmp'd out of OPERATE. */
*errstring = signalled_errstring;
*objname = signalled_objname;
- return *errstring ? errcode : 0;
+ return errcode == -1 ? 0 : errcode;
}
diff --git a/elf/dl-fini.c b/elf/dl-fini.c
index cbc0525..69ff83d 100644
--- a/elf/dl-fini.c
+++ b/elf/dl-fini.c
@@ -26,5 +26,5 @@ _dl_fini (void)
for (l = _dl_loaded; l; l = l->l_next)
if (l->l_init_called && l->l_info[DT_FINI])
- (*(void (*) (void)) l->l_info[DT_FINI]->d_un.d_ptr) ();
+ (*(void (*) (void)) (l->l_addr + l->l_info[DT_FINI]->d_un.d_ptr)) ();
}
diff --git a/elf/dl-init.c b/elf/dl-init.c
index e3bfc2c..36eb32a 100644
--- a/elf/dl-init.c
+++ b/elf/dl-init.c
@@ -46,15 +46,17 @@ _dl_init_next (void)
{
/* Find each dependency in order, and see if it
needs to run an initializer. */
+ const char *strtab
+ = ((void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr);
const Elf32_Dyn *d;
for (d = l->l_ld; d->d_tag != DT_NULL; ++d)
if (d->d_tag == DT_NEEDED)
{
- struct link_map *needed = _dl_map_object
- (l, (const char *) (l->l_addr + d->d_un.d_ptr), NULL);
+ struct link_map *needed
+ = _dl_map_object (l, strtab + d->d_un.d_val, NULL);
Elf32_Addr init;
--needed->l_opencount;
- init = next_init (l); /* Recurse on this dependency. */
+ init = next_init (needed); /* Recurse on this dependency. */
if (init != 0)
return init;
}
@@ -74,7 +76,7 @@ _dl_init_next (void)
}
/* Look for the first initializer not yet called. */
- l = _dl_loaded;
+ l = _dl_loaded->l_next; /* Skip the executable itself. */
do
{
init = next_init (l);
diff --git a/elf/dl-load.c b/elf/dl-load.c
index f8b37ba..bb1ad97 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -158,11 +158,12 @@ _dl_map_object (struct link_map *loader, const char *name,
size_t namelen = strlen (name) + 1;
- void trypath (const char *dirpath)
+ inline void trypath (const char *dirpath)
{
fd = open_path (name, namelen, dirpath, &realname);
}
+ fd = -1;
if (loader && loader->l_info[DT_RPATH])
trypath ((const char *) (loader->l_addr +
loader->l_info[DT_RPATH]->d_un.d_ptr));
@@ -317,14 +318,14 @@ _dl_map_object (struct link_map *loader, const char *name,
if (ph->p_memsz > ph->p_filesz)
{
/* Extra zero pages should appear at the end of this segment,
- after the data mapped from the file. Adjust MAPEND to map
- only the data from the file. We will later allocate zero
- pages following the data mapping. */
- caddr_t zero = mapat - mapstart + ph->p_filesz;
- caddr_t zeroend = mapat - mapstart + ph->p_memsz;
- caddr_t zeropage
- = (caddr_t) ((Elf32_Addr) (zero + pagesize - 1)
- & ~(pagesize - 1));
+ after the data mapped from the file. */
+ caddr_t zero, zeroend, zeropage;
+
+ mapat += ph->p_vaddr - mapstart;
+ zero = mapat + ph->p_filesz;
+ zeroend = mapat + ph->p_memsz;
+ zeropage = (caddr_t) ((Elf32_Addr) (zero + pagesize - 1)
+ & ~(pagesize - 1));
if (zeroend < zeropage)
/* All the extra data is in the last page of the segment.
@@ -342,7 +343,7 @@ _dl_map_object (struct link_map *loader, const char *name,
prot|PROT_WRITE) < 0)
lose (errno, "cannot change memory protections");
}
- memset (zero, 0, zeroend - zero);
+ memset (zero, 0, zeropage - zero);
if ((prot & PROT_WRITE) == 0)
mprotect ((caddr_t) ((Elf32_Addr) zero
& ~(pagesize - 1)),
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index a7afcc7..4d5d795 100644
--- a/elf/dl-lookup.c
+++ b/elf/dl-lookup.c
@@ -20,6 +20,7 @@ Cambridge, MA 02139, USA. */
#include <stddef.h>
#include <libelf.h>
#include <link.h>
+#include <assert.h>
/* Search loaded objects' symbol tables for a definition of
the symbol UNDEF_NAME. Don't use a PLT defn in UNDEF_MAP, since
@@ -70,13 +71,13 @@ _dl_lookup_symbol (const char *undef_name, const Elf32_Sym **ref,
continue;
}
- if (sym == *ref)
+ if (sym->st_shndx == SHN_UNDEF)
/* This is the same symbol we are looking for the value for.
If it is a PLT entry, it will have a value of its own;
but that is not what we are looking for. */
- continue;
+ continue;
- if (strcmp (strtab + sym->st_name, undef_name))
+ if (sym != *ref && strcmp (strtab + sym->st_name, undef_name))
/* Not the symbol we are looking for. */
continue;
@@ -106,8 +107,8 @@ _dl_lookup_symbol (const char *undef_name, const Elf32_Sym **ref,
const char msg[] = "undefined symbol: ";
char buf[sizeof msg + strlen (undef_name)];
memcpy (buf, msg, sizeof msg - 1);
- memcpy (&buf[sizeof msg - 1], undef_name, sizeof buf - sizeof msg);
- _dl_signal_error (0, reference_name, msg);
+ memcpy (&buf[sizeof msg - 1], undef_name, sizeof buf - sizeof msg + 1);
+ _dl_signal_error (0, reference_name, buf);
}
*ref = weak_value.s;
diff --git a/elf/dl-reloc.c b/elf/dl-reloc.c
index 94ffb71..ebc31d0 100644
--- a/elf/dl-reloc.c
+++ b/elf/dl-reloc.c
@@ -83,7 +83,7 @@ _dl_relocate_object (struct link_map *l, int lazy)
l->l_prev->l_next = l;
}
- if (l->l_info[DT_JMPREL] && ! lazy)
+ if (l->l_info[DT_JMPREL] && lazy)
/* Set up the PLT so its unrelocated entries will
jump to _dl_runtime_resolve, which will relocate them. */
elf_machine_runtime_setup (l);
diff --git a/elf/do-rel.h b/elf/do-rel.h
index 04643e8..acef25d 100644
--- a/elf/do-rel.h
+++ b/elf/do-rel.h
@@ -30,37 +30,46 @@ Cambridge, MA 02139, USA. */
/* Perform the relocations in MAP on the running program image as specified
by RELTAG, SZTAG. *RESOLVE is called to resolve symbol values; it
modifies its argument pointer to point to the defining symbol, and
- returns the base load address of the defining object. */
+ returns the base load address of the defining object. If LAZY is
+ nonzero, this is the first pass on PLT relocations; they should be set
+ up to call _dl_runtime_resolve, rather than fully resolved now. */
static inline void
elf_dynamic_do_rel (struct link_map *map,
int reltag, int sztag,
- Elf32_Addr (*resolve) (const Elf32_Sym **))
+ Elf32_Addr (*resolve) (const Elf32_Sym **),
+ int lazy)
{
const Elf32_Sym *const symtab
- = (const Elf32_Sym *) map->l_info[DT_SYMTAB]->d_un.d_ptr;
- const Elf32_Rel *r = (const Elf32_Rel *) map->l_info[reltag]->d_un.d_ptr;
+ = (const Elf32_Sym *) (map->l_addr + map->l_info[DT_SYMTAB]->d_un.d_ptr);
+ const Elf32_Rel *r
+ = (const Elf32_Rel *) (map->l_addr + map->l_info[reltag]->d_un.d_ptr);
const Elf32_Rel *end = &r[map->l_info[sztag]->d_un.d_val / sizeof *r];
- for (; r < end; ++r)
- {
- const Elf32_Sym *definer = &symtab[ELF32_R_SYM (r->r_info)];
- Elf32_Addr loadbase;
+ if (lazy)
+ /* Doing lazy PLT relocations; they need very little info. */
+ for (; r < end; ++r)
+ elf_machine_lazy_rel (map, r);
+ else
+ for (; r < end; ++r)
+ {
+ const Elf32_Sym *definer = &symtab[ELF32_R_SYM (r->r_info)];
+ Elf32_Addr loadbase;
- if (ELF32_R_SYM (r->r_info) == STN_UNDEF)
- loadbase = 0; /* This value will not be consulted. */
- else
- {
- if (resolve)
- loadbase = (*resolve) (&definer);
- else
- {
- assert (definer->st_shndx != SHN_UNDEF);
- loadbase = map->l_addr;
- }
- }
- elf_machine_rel (map, r, loadbase, definer);
- }
+ if (ELF32_R_SYM (r->r_info) == STN_UNDEF)
+ loadbase = 0; /* This value will not be consulted. */
+ else
+ {
+ if (resolve)
+ loadbase = (*resolve) (&definer);
+ else
+ {
+ assert (definer->st_shndx != SHN_UNDEF);
+ loadbase = map->l_addr;
+ }
+ }
+ elf_machine_rel (map, r, loadbase, definer);
+ }
}
#undef elf_dynamic_do_rel
diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h
index fc5c585..a7316ee 100644
--- a/elf/dynamic-link.h
+++ b/elf/dynamic-link.h
@@ -56,9 +56,9 @@ elf_get_dynamic_info (Elf32_Dyn *dyn, Elf32_Dyn *info[DT_NUM])
#include "do-rel.h"
#define ELF_DYNAMIC_DO_REL(map, lazy, resolve) \
if ((map)->l_info[DT_REL]) \
- elf_dynamic_do_rel ((map), DT_REL, DT_RELSZ, (resolve)); \
- if (!(lazy) && (map)->l_info[DT_PLTREL]->d_un.d_val == DT_REL) \
- elf_dynamic_do_rel ((map), DT_JMPREL, DT_PLTRELSZ, (resolve));
+ elf_dynamic_do_rel ((map), DT_REL, DT_RELSZ, (resolve), 0); \
+ if ((map)->l_info[DT_PLTREL]->d_un.d_val == DT_REL) \
+ elf_dynamic_do_rel ((map), DT_JMPREL, DT_PLTRELSZ, (resolve), (lazy));
#else
#define ELF_DYNAMIC_DO_RELA(map, lazy, resolve) /* Nothing to do. */
#endif
@@ -68,9 +68,9 @@ elf_get_dynamic_info (Elf32_Dyn *dyn, Elf32_Dyn *info[DT_NUM])
#include "do-rel.h"
#define ELF_DYNAMIC_DO_RELA(map, lazy, resolve) \
if ((map)->l_info[DT_RELA]) \
- elf_dynamic_do_rela ((map), DT_RELA, DT_RELASZ, (resolve)); \
- if (!(lazy) && (map)->l_info[DT_PLTREL]->d_un.d_val == DT_RELA) \
- elf_dynamic_do_rela ((map), DT_JMPREL, DT_PLTRELSZ, (resolve);
+ elf_dynamic_do_rela ((map), DT_RELA, DT_RELASZ, (resolve), 0); \
+ if ((map)->l_info[DT_PLTREL]->d_un.d_val == DT_RELA) \
+ elf_dynamic_do_rela ((map), DT_JMPREL, DT_PLTRELSZ, (resolve), (lazy));
#else
#define ELF_DYNAMIC_DO_RELA(map, lazy, resolve) /* Nothing to do. */
#endif
diff --git a/elf/rtld.c b/elf/rtld.c
index 85f258a..409b970 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -93,6 +93,8 @@ _dl_start (void *arg)
void _start (void);
+static int rtld_command; /* Nonzero if we were run directly. */
+
static void
dl_main (const Elf32_Phdr *phdr,
Elf32_Word phent,
@@ -138,6 +140,7 @@ file you run. This is mostly of use for maintainers to test new versions\n\
of this helper program; chances are you did not intend to run this program.\n"
);
+ rtld_command = 1;
interpreter_name = _dl_argv[0];
--_dl_argc;
++_dl_argv;
@@ -164,7 +167,7 @@ of this helper program; chances are you did not intend to run this program.\n"
case PT_DYNAMIC:
/* This tells us where to find the dynamic section,
which tells us everything we need to do. */
- l->l_ld = (void *) ph->p_vaddr;
+ l->l_ld = (void *) l->l_addr + ph->p_vaddr;
break;
case PT_INTERP:
/* This "interpreter segment" was used by the program loader to
@@ -173,7 +176,7 @@ of this helper program; chances are you did not intend to run this program.\n"
dlopen call or DT_NEEDED entry, for something that wants to link
against the dynamic linker as a shared library, will know that
the shared object is already loaded. */
- interpreter_name = (void *) ph->p_vaddr;
+ interpreter_name = (void *) l->l_addr + ph->p_vaddr;
break;
}
assert (interpreter_name); /* How else did we get here? */
@@ -220,7 +223,7 @@ of this helper program; chances are you did not intend to run this program.\n"
l->l_next->l_prev = l->l_prev;
}
- lazy = _dl_secure || *(getenv ("LD_BIND_NOW") ?: "");
+ lazy = !_dl_secure && *(getenv ("LD_BIND_NOW") ?: "") == '\0';
/* Now we have all the objects loaded. Relocate them all.
We do this in reverse order so that copy relocs of earlier
diff --git a/sysdeps/i386/dl-machine.h b/sysdeps/i386/dl-machine.h
index 1797ae5..f387a88 100644
--- a/sysdeps/i386/dl-machine.h
+++ b/sysdeps/i386/dl-machine.h
@@ -75,7 +75,7 @@ elf_machine_rel (struct link_map *map,
const Elf32_Rel *reloc,
Elf32_Addr sym_loadaddr, const Elf32_Sym *sym)
{
- Elf32_Addr *const reloc_addr = (Elf32_Addr *) reloc->r_offset;
+ Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
const Elf32_Addr sym_value = sym_loadaddr + sym->st_value;
switch (ELF32_R_TYPE (reloc->r_info))
@@ -102,6 +102,20 @@ elf_machine_rel (struct link_map *map,
}
}
+static inline void
+elf_machine_lazy_rel (struct link_map *map, const Elf32_Rel *reloc)
+{
+ Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
+ switch (ELF32_R_TYPE (reloc->r_info))
+ {
+ case R_386_JMP_SLOT:
+ *reloc_addr += map->l_addr;
+ break;
+ default:
+ assert (! "unexpected PLT reloc type");
+ break;
+ }
+}
/* The i386 never uses Elf32_Rela relocations. */
#define ELF_MACHINE_NO_RELA 1
@@ -113,12 +127,14 @@ elf_machine_rel (struct link_map *map,
static inline void
elf_machine_runtime_setup (struct link_map *l)
{
+ Elf32_Addr *got;
extern void _dl_runtime_resolve (Elf32_Word);
+
/* The GOT entries for functions in the PLT have not yet been filled
in. Their initial contents will arrange when called to push an
offset into the .rel.plt section, push _GLOBAL_OFFSET_TABLE_[1],
and then jump to _GLOBAL_OFFSET_TABLE[2]. */
- Elf32_Addr *got = (Elf32_Addr *) l->l_info[DT_PLTGOT]->d_un.d_ptr;
+ got = (Elf32_Addr *) (l->l_addr + l->l_info[DT_PLTGOT]->d_un.d_ptr);
got[1] = (Elf32_Addr) l; /* Identify this shared object. */
/* This function will get called to fix up the GOT entry indicated by
the offset on the stack, and then jump to the resolved address. */
@@ -140,9 +156,20 @@ _dl_start_user:\n\
# Save the user entry point address in %edi.\n\
movl %eax, %edi\n\
# Point %ebx at the GOT.
-1: call 2f\n\
-2: popl %ebx\n\
- addl $_GLOBAL_OFFSET_TABLE_+[.-2b], %ebx\n\
+ call 0f\n\
+0: popl %ebx\n\
+ addl $_GLOBAL_OFFSET_TABLE_+[.-0b], %ebx\n\
+ # See if we were run as a command with the executable file\n\
+ # name as an extra leading argument.\n\
+ movl rtld_command@GOT(%ebx), %eax\n\
+ movl (%eax),%eax\n\
+ testl %eax,%eax\n\
+ jz 0f\n\
+ # Pop the original argument count, decrement it, and replace\n\
+ # the original first argument pointer with the new count.\n\
+ popl %eax\n\
+ decl %eax\n\
+ movl %eax,(%esp)\n\
# Call _dl_init_next to return the address of an initializer\n\
# function to run.\n\
0: call _dl_init_next@PLT\n\
@@ -150,7 +177,7 @@ _dl_start_user:\n\
testl %eax,%eax\n\
jz 1f\n\
# Call the shared object initializer function.\n\
- # NOTE: We depend only on the registers (%ebx)\n\
+ # NOTE: We depend only on the registers (%ebx and %edi)\n\
# and the return address pushed by this call;\n\
# the initializer is called with the stack just\n\
# as it appears on entry, and it is free to move\n\
@@ -159,8 +186,8 @@ _dl_start_user:\n\
call *%eax\n\
# Loop to call _dl_init_next for the next initializer.\n\
jmp 0b\n\
- # Pass our finalizer function to the user in %edx, as per ELF ABI.\n\
- leal _dl_fini@GOT(%ebx), %edx\n\
+1: # Pass our finalizer function to the user in %edx, as per ELF ABI.\n\
+ movl _dl_fini@GOT(%ebx), %edx\n\
# Jump to the user's entry point.\n\
jmp *%edi\n\
");
diff --git a/sysdeps/i386/dl-runtime.c b/sysdeps/i386/dl-runtime.c
index 1bc5697..8e218e2 100644
--- a/sysdeps/i386/dl-runtime.c
+++ b/sysdeps/i386/dl-runtime.c
@@ -34,15 +34,16 @@ void
_dl_runtime_resolve (Elf32_Word reloc_offset)
{
__label__ return_insn;
- struct link_map *l = (void *) &(&reloc_offset)[-1];
+ struct link_map *l = (void *) (&reloc_offset)[-1];
const Elf32_Sym *const symtab
- = (const Elf32_Sym *) l->l_info[DT_SYMTAB]->d_un.d_ptr;
- const char *strtab
- = ((void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr);
+ = (const Elf32_Sym *) (l->l_addr + l->l_info[DT_SYMTAB]->d_un.d_ptr);
+ const char *strtab =
+ (const char *) (l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr);
- const Elf32_Rel *const reloc = (void *) (l->l_info[DT_JMPREL]->d_un.d_ptr
- + reloc_offset);
+ const Elf32_Rel *const reloc
+ = (const void *) (l->l_addr + l->l_info[DT_JMPREL]->d_un.d_ptr +
+ reloc_offset);
const Elf32_Sym *definer;
Elf32_Addr loadbase;
@@ -83,7 +84,7 @@ _dl_runtime_resolve (Elf32_Word reloc_offset)
referred to by this PLT entry; once "ret" pops this address, the
function in the shared object will run with the stack arranged just as
when the user entered the PLT. */
- (&reloc_offset)[0] = *(Elf32_Word *) reloc->r_offset;
+ (&reloc_offset)[0] = *(Elf32_Word *) (l->l_addr + reloc->r_offset);
return;
diff --git a/sysdeps/mach/hurd/dl-sysdep.c b/sysdeps/mach/hurd/dl-sysdep.c
index 1dca319..d484521 100644
--- a/sysdeps/mach/hurd/dl-sysdep.c
+++ b/sysdeps/mach/hurd/dl-sysdep.c
@@ -36,6 +36,8 @@ Cambridge, MA 02139, USA. */
#include "dl-machine.h"
+extern void __mach_init (void);
+
extern int _dl_argc;
extern char **_dl_argv;
extern char **_environ;
@@ -52,8 +54,8 @@ _dl_sysdep_start (void **start_argptr,
char **p;
/* Cache the information in various global variables. */
- _dl_argc = *argdata++;
- _dl_argv = (void *) argdata;
+ _dl_argc = *argdata;
+ _dl_argv = (void *) &argdata[1];
_environ = &_dl_argv[_dl_argc + 1];
for (p = _environ; *p; ++p);
_dl_hurd_data = (void *) ++p;
@@ -66,6 +68,12 @@ _dl_sysdep_start (void **start_argptr,
_dl_hurd_data->phdrsz / sizeof (Elf32_Phdr),
&_dl_hurd_data->user_entry);
+ /* Deallocate the reply port and task port rights acquired by
+ __mach_init. We are done with them now, and the user will
+ reacquire them for himself when he wants them. */
+ __mig_dealloc_reply_port (MACH_PORT_NULL);
+ __mach_port_deallocate (__mach_task_self (), __mach_task_self_);
+
{
extern void _dl_start_user (void);
/* Unwind the stack to ARGDATA and simulate a return from _dl_start
@@ -74,6 +82,9 @@ _dl_sysdep_start (void **start_argptr,
}
}
+ /* Set up so we can do RPCs. */
+ __mach_init ();
+
/* See hurd/hurdstartup.c; this deals with getting information
from the exec server and slicing up the arguments.
Then it will call `go', above. */
diff --git a/sysdeps/mach/hurd/i386/init-first.c b/sysdeps/mach/hurd/i386/init-first.c
index d747e75..74b15c8 100644
--- a/sysdeps/mach/hurd/i386/init-first.c
+++ b/sysdeps/mach/hurd/i386/init-first.c
@@ -95,8 +95,8 @@ init1 (int argc, char *arg0, ...)
__libc_init (argc, argv, __environ);
}
-static void
-init (int *data, int retaddr)
+static void
+init (int *data, void *usercode, void **retaddrloc)
{
int argc = *data;
char **argv = (void *) (data + 1);
@@ -115,6 +115,11 @@ init (int *data, int retaddr)
if (__hurd_threadvar_max < _HURD_THREADVAR_MAX)
__hurd_threadvar_max = _HURD_THREADVAR_MAX;
+
+ /* After possibly switching stacks, call `init1' (above) with the user
+ code as the return address, and the argument data immediately above
+ that on the stack. */
+
if (_cthread_init_routine)
{
/* Initialize cthreads, which will allocate us a new stack to run on. */
@@ -136,13 +141,45 @@ init (int *data, int retaddr)
/* Copy the Hurd startup data block to the new stack. */
*od = *d;
- data = newsp;
+ /* Push the user code address on the top of the new stack. It will
+ be the return address for `init1'; we will jump there with NEWSP
+ as the stack pointer. */
+ *--(void **) newsp = usercode;
+ /* Mutate our own return address to run the code below. */
+ *retaddrloc = &&switch_stacks;
+ /* Force NEWSP into %ecx and &init1 into %eax, which are not restored
+ by function return. */
+ asm volatile ("# a %0 c %1" : : "a" (&init1), "c" (newsp));
+ return;
+ switch_stacks:
+ /* Our return address was redirected to here, so at this point our
+ stack is unwound and callers' registers restored. Only %ecx and
+ %eax are call-clobbered and thus still have the values we set just
+ above. Fetch from there the new stack pointer we will run on, and
+ jmp to the run-time address of `init1'; when it returns, it will
+ run the user code with the argument data at the top of the stack. */
+ asm volatile ("movl %ecx, %esp; jmp *%eax");
+ /* NOTREACHED */
+ }
+ else
+ {
+ /* We are not switching stacks, but we must play some games with
+ the one we've got, similar to the stack-switching code above. */
+ *retaddrloc = &&call_init1;
+ /* Force the user code address into %ecx and the run-time address of
+ `init1' into %eax, for use below. */
+ asm volatile ("# a %0 c %1" : : "a" (&init1), "c" (usercode));
+ return;
+ call_init1:
+ /* As in the stack-switching case, at this point our stack is unwound
+ and callers' registers restored, and only %ecx and %eax
+ communicate values from the lines above. In this case we have
+ stashed in %ecx the user code return address. Push it on the top
+ of the stack so it acts as init1's return address, and then jump
+ there. */
+ asm volatile ("pushl %ecx; jmp *%eax");
+ /* NOTREACHED */
}
-
- /* Call `init1' (above) with the user code as the return address,
- and the argument data immediately above that on the stack. */
- *--data = retaddr;
- asm volatile ("movl %0, %%esp; jmp %*%1" : : "g" (data), "r" (&init1));
}
@@ -151,30 +188,32 @@ init (int *data, int retaddr)
It is called just before the user _start code from i386/elf/start.S,
with the stack set up as that code gets it. */
-static void soinit (int argc, ...) __attribute__ ((unused, section (".init")));
+/* NOTE! The linker notices the magical name `_init' and sets the DT_INIT
+ pointer in the dynamic section based solely on that. It is convention
+ for this function to be in the `.init' section, but the symbol name is
+ the only thing that really matters!! */
+/*void _init (int argc, ...) __attribute__ ((unused, section (".init")));*/
-static void
-soinit (int argc, ...)
+void
+_init (int argc, ...)
{
/* Initialize data structures so we can do RPCs. */
__mach_init ();
RUN_HOOK (_hurd_preinit_hook, ());
- init (&argc, (&argc)[-1]);
-
- (void) &soinit; /* Avoid gcc optimizing this fn out. */
+ init (&argc, ((void **) &argc)[-1], &((void **) &argc)[-1]);
}
#endif
void
-__libc_init_first (int argc, ...)
+__libc_init_first (int argc __attribute__ ((unused)), ...)
{
#ifndef PIC
void doinit (int *data)
{
- init (data, (&argc)[-1]);
+ init (data, ((void **) &argc)[-1], &((void **) &data)[-1]);
}
/* Initialize data structures so we can do RPCs. */