| /* HP-UX host-specific hook definitions. |
| Copyright (C) 2004-2021 Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC 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 3, or (at your |
| option) any later version. |
| |
| GCC 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 GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "hosthooks.h" |
| #include "hosthooks-def.h" |
| |
| static void *hpux_gt_pch_get_address (size_t, int); |
| static int hpux_gt_pch_use_address (void *, size_t, int, size_t); |
| |
| #undef HOST_HOOKS_GT_PCH_GET_ADDRESS |
| #define HOST_HOOKS_GT_PCH_GET_ADDRESS hpux_gt_pch_get_address |
| #undef HOST_HOOKS_GT_PCH_USE_ADDRESS |
| #define HOST_HOOKS_GT_PCH_USE_ADDRESS hpux_gt_pch_use_address |
| |
| /* For various ports, try to guess a fixed spot in the vm space |
| that's probably free. */ |
| #if (defined(__hppa__) || defined(__ia64__)) && defined(__LP64__) |
| # define TRY_EMPTY_VM_SPACE 0x8000000000000000 |
| #elif defined(__hppa__) || defined(__ia64__) |
| # define TRY_EMPTY_VM_SPACE 0x60000000 |
| #else |
| # define TRY_EMPTY_VM_SPACE 0 |
| #endif |
| |
| /* Determine a location where we might be able to reliably allocate |
| SIZE bytes. FD is the PCH file, though we should return with the |
| file unmapped. */ |
| |
| static void * |
| hpux_gt_pch_get_address (size_t size, int fd) |
| { |
| void *addr; |
| |
| addr = mmap ((void *)TRY_EMPTY_VM_SPACE, size, PROT_READ | PROT_WRITE, |
| MAP_PRIVATE, fd, 0); |
| |
| /* If we failed the map, that means there's *no* free space. */ |
| if (addr == (void *) MAP_FAILED) |
| return NULL; |
| /* Unmap the area before returning. */ |
| munmap (addr, size); |
| |
| return addr; |
| } |
| |
| /* Map SIZE bytes of FD+OFFSET at BASE. Return 1 if we succeeded at |
| mapping the data at BASE, -1 if we couldn't. |
| |
| It's not possibly to reliably mmap a file using MAP_PRIVATE to |
| a specific START address on either hpux or linux. First we see |
| if mmap with MAP_PRIVATE works. If it does, we are off to the |
| races. If it doesn't, we try an anonymous private mmap since the |
| kernel is more likely to honor the BASE address in anonymous maps. |
| We then copy the data to the anonymous private map. This assumes |
| of course that we don't need to change the data in the PCH file |
| after it is created. |
| |
| This approach obviously causes a performance penalty but there is |
| little else we can do given the current PCH implementation. */ |
| |
| static int |
| hpux_gt_pch_use_address (void *base, size_t size, int fd, size_t offset) |
| { |
| void *addr; |
| |
| /* We're called with size == 0 if we're not planning to load a PCH |
| file at all. This allows the hook to free any static space that |
| we might have allocated at link time. */ |
| if (size == 0) |
| return -1; |
| |
| /* Try to map the file with MAP_PRIVATE. */ |
| addr = mmap (base, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, offset); |
| |
| if (addr == base) |
| return 1; |
| |
| if (addr != (void *) MAP_FAILED) |
| munmap (addr, size); |
| |
| /* Try to make an anonymous private mmap at the desired location. */ |
| addr = mmap (base, size, PROT_READ | PROT_WRITE, |
| MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| |
| if (addr != base) |
| { |
| if (addr != (void *) MAP_FAILED) |
| munmap (addr, size); |
| return -1; |
| } |
| |
| if (lseek (fd, offset, SEEK_SET) == (off_t)-1) |
| return -1; |
| |
| while (size) |
| { |
| ssize_t nbytes; |
| |
| nbytes = read (fd, base, MIN (size, SSIZE_MAX)); |
| if (nbytes <= 0) |
| return -1; |
| base = (char *) base + nbytes; |
| size -= nbytes; |
| } |
| |
| return 1; |
| } |
| |
| |
| const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER; |