From 45c39ff3e09accefdc514d01f5cda8e940326122 Mon Sep 17 00:00:00 2001 From: "Michael I. Bushnell" Date: Mon, 25 Mar 1996 21:59:46 +0000 Subject: Initial revision --- libshouldbeinlibc/wire.c | 153 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 libshouldbeinlibc/wire.c diff --git a/libshouldbeinlibc/wire.c b/libshouldbeinlibc/wire.c new file mode 100644 index 00000000..faf53132 --- /dev/null +++ b/libshouldbeinlibc/wire.c @@ -0,0 +1,153 @@ +/* Function to wire down text and data (including from shared libraries) + Copyright (C) 1996 Free Software Foundation, Inc. + Written by Michael I. Bushnell, p/BSG. + + This file is part of the GNU Hurd. + + The GNU Hurd is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License as + published by the Free Software Foundation; either version 2, or (at + your option) any later version. + + The GNU Hurd 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA. */ + + +#include +#include +#include + +/* Find the list of shared objects */ +static struct link_map * +loaded (void) +{ + Elf32_Dyn *d; + + for (d = _DYNAMIC; d->d_tag != DT_NULL; ++d) + if (d->d_tag == DT_DEBUG) + { + struct r_debug *r = (void *) d->d_un.d_ptr; + return r->r_map; + } + + return 0; /* ld broken */ +} + +/* Compute the extent of a particular shared object. */ +static Elf32_Addr +map_extent (struct link_map *map) +{ + /* Find the last load cmd; they are in ascending p_vaddr order. */ + Elf32_Word n = map->l_phnum; + while (n-- > 0 && map->l_phdr[n].p_type != PT_LOAD); + return map->l_phdr[n].p_vaddr + map->l_phdr[n].p_filesz; +} + +/* Wire down all memory currently allocated at START for LEN bytes; + host_priv is the privileged host port. */ +static void +wire_segment_internal (vm_address_t start, + vm_size_t len, + host_priv_t host_priv) +{ + vm_address_t addr; + vm_size_t size; + vm_prot_t protection; + vm_prot_t max_protection; + vm_inherit_t inheritance; + boolean_t shared; + mach_port_t object_name; + vm_offset_t offset; + error_t err; + + do + { + addr = start; + err = vm_region (mach_task_self (), &addr, &size, &protection, + &max_protection, &inheritance, &shared, &object_name, + &offset); + if (err) + return; + + /* The current region begins at ADDR and is SIZE long. If it + extends beyond the LEN, prune it. */ + if (addr + size > start + len) + size = len - (addr - start); + + /* Set protection to allow all access possible */ + vm_protect (mach_task_self (), addr, size, 0, max_protection); + + /* Wire pages */ + vm_wire (host_priv, mach_task_self (), addr, size, max_protection); + + /* Set protection back to what it was */ + vm_protect (mach_task_self (), addr, size, 0, protection); + + mach_port_deallocate (mach_task_self (), object_name); + + len -= (addr - start) + size; + start = addr + size; + } + while (len); +} + +/* Wire down all memory currently allocated at START for LEN bytes. */ +void +wire_segment (vm_address_t start, + vm_size_t len) +{ + mach_port_t host, device; + error_t error; + + error = get_privileged_ports (&host, &device); + if (!error) + { + wire_segment_internal (start, len, host); + mach_port_deallocate (mach_task_self (), host); + mach_port_deallocate (mach_task_self (), device); + } +} + + +/* Wire down all the text and data (including from shared libraries) + for the current program. */ +void +wire_task_self () +{ + struct link_map *map; + mach_port_t host, device; + error_t error; + extern char _edata, _etext, __data_start; + + error = get_privileged_ports (&host, &device); + if (error) + return; + + map = loaded (); + if (!map) + { + extern void _start (); + vm_address_t text_start = (vm_address_t) &_start; + wire_segment_internal (text_start, + (vm_size_t) (&_etext - text_start), + host); + wire_segment_internal ((vm_address_t) &__data_start, + (vm_size_t) (&_edata - &__data_start), + host); + } + else + while (map) + wire_segment ((vm_address_t) map->l_addr, map_extent (map)); + + mach_port_deallocate (mach_task_self (), host); + mach_port_deallocate (mach_task_self (), device); +} + + + -- cgit v1.2.3