| |
| /*--------------------------------------------------------------------*/ |
| /*--- For when the client advises Valgrind about memory ---*/ |
| /*--- permissions. ---*/ |
| /*--- mc_clientreqs.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of MemCheck, a heavyweight Valgrind skin for |
| detecting memory errors. |
| |
| Copyright (C) 2000-2003 Julian Seward |
| jseward@acm.org |
| |
| This program 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 of the |
| License, or (at your option) any later version. |
| |
| This program 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 |
| 02111-1307, USA. |
| |
| The GNU General Public License is contained in the file COPYING. |
| */ |
| |
| #include "mc_include.h" |
| |
| #include "memcheck.h" /* for VG_USERREQ__* */ |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- General client block management. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* This is managed as an expanding array of client block descriptors. |
| Indices of live descriptors are issued to the client, so it can ask |
| to free them later. Therefore we cannot slide live entries down |
| over dead ones. Instead we must use free/inuse flags and scan for |
| an empty slot at allocation time. This in turn means allocation is |
| relatively expensive, so we hope this does not happen too often. |
| */ |
| |
| typedef |
| enum { CG_NotInUse, CG_NoAccess, CG_Writable, CG_Readable } |
| CGenBlockKind; |
| |
| typedef |
| struct { |
| Addr start; |
| UInt size; |
| ExeContext* where; |
| CGenBlockKind kind; |
| } |
| CGenBlock; |
| |
| /* This subsystem is self-initialising. */ |
| static UInt vg_cgb_size = 0; |
| static UInt vg_cgb_used = 0; |
| static CGenBlock* vg_cgbs = NULL; |
| |
| /* Stats for this subsystem. */ |
| static UInt vg_cgb_used_MAX = 0; /* Max in use. */ |
| static UInt vg_cgb_allocs = 0; /* Number of allocs. */ |
| static UInt vg_cgb_discards = 0; /* Number of discards. */ |
| static UInt vg_cgb_search = 0; /* Number of searches. */ |
| |
| |
| static |
| Int vg_alloc_client_block ( void ) |
| { |
| UInt i, sz_new; |
| CGenBlock* cgbs_new; |
| |
| vg_cgb_allocs++; |
| |
| for (i = 0; i < vg_cgb_used; i++) { |
| vg_cgb_search++; |
| if (vg_cgbs[i].kind == CG_NotInUse) |
| return i; |
| } |
| |
| /* Not found. Try to allocate one at the end. */ |
| if (vg_cgb_used < vg_cgb_size) { |
| vg_cgb_used++; |
| return vg_cgb_used-1; |
| } |
| |
| /* Ok, we have to allocate a new one. */ |
| sk_assert(vg_cgb_used == vg_cgb_size); |
| sz_new = (vg_cgbs == NULL) ? 10 : (2 * vg_cgb_size); |
| |
| cgbs_new = VG_(malloc)( sz_new * sizeof(CGenBlock) ); |
| for (i = 0; i < vg_cgb_used; i++) |
| cgbs_new[i] = vg_cgbs[i]; |
| |
| if (vg_cgbs != NULL) |
| VG_(free)( vg_cgbs ); |
| vg_cgbs = cgbs_new; |
| |
| vg_cgb_size = sz_new; |
| vg_cgb_used++; |
| if (vg_cgb_used > vg_cgb_used_MAX) |
| vg_cgb_used_MAX = vg_cgb_used; |
| return vg_cgb_used-1; |
| } |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- Externally visible functions. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| void MC_(show_client_block_stats) ( void ) |
| { |
| VG_(message)(Vg_DebugMsg, |
| "general CBs: %d allocs, %d discards, %d maxinuse, %d search", |
| vg_cgb_allocs, vg_cgb_discards, vg_cgb_used_MAX, vg_cgb_search |
| ); |
| } |
| |
| Bool MC_(client_perm_maybe_describe)( Addr a, AddrInfo* ai ) |
| { |
| UInt i; |
| /* VG_(printf)("try to identify %d\n", a); */ |
| |
| /* Perhaps it's a general block ? */ |
| for (i = 0; i < vg_cgb_used; i++) { |
| if (vg_cgbs[i].kind == CG_NotInUse) |
| continue; |
| if (VG_(addr_is_in_block)(a, vg_cgbs[i].start, vg_cgbs[i].size)) { |
| ai->akind = UserG; |
| ai->blksize = vg_cgbs[i].size; |
| ai->rwoffset = (Int)(a) - (Int)(vg_cgbs[i].start); |
| ai->lastchange = vg_cgbs[i].where; |
| return True; |
| } |
| } |
| return False; |
| } |
| |
| Bool SK_(handle_client_request) ( ThreadState* tst, UInt* arg, UInt* ret ) |
| { |
| Int i; |
| Bool ok; |
| Addr bad_addr; |
| |
| if (!VG_IS_SKIN_USERREQ('M','C',arg[0])) |
| return False; |
| |
| switch (arg[0]) { |
| case VG_USERREQ__CHECK_WRITABLE: /* check writable */ |
| ok = MC_(check_writable) ( arg[1], arg[2], &bad_addr ); |
| if (!ok) |
| MC_(record_user_error) ( tst, bad_addr, True ); |
| *ret = ok ? (UInt)NULL : bad_addr; |
| break; |
| |
| case VG_USERREQ__CHECK_READABLE: /* check readable */ |
| ok = MC_(check_readable) ( arg[1], arg[2], &bad_addr ); |
| if (!ok) |
| MC_(record_user_error) ( tst, bad_addr, False ); |
| *ret = ok ? (UInt)NULL : bad_addr; |
| break; |
| |
| case VG_USERREQ__DO_LEAK_CHECK: |
| MC_(detect_memory_leaks)(); |
| *ret = 0; /* return value is meaningless */ |
| break; |
| |
| case VG_USERREQ__MAKE_NOACCESS: /* make no access */ |
| i = vg_alloc_client_block(); |
| /* VG_(printf)("allocated %d %p\n", i, vg_cgbs); */ |
| vg_cgbs[i].kind = CG_NoAccess; |
| vg_cgbs[i].start = arg[1]; |
| vg_cgbs[i].size = arg[2]; |
| vg_cgbs[i].where = VG_(get_ExeContext) ( tst ); |
| MC_(make_noaccess) ( arg[1], arg[2] ); |
| *ret = i; |
| break; |
| |
| case VG_USERREQ__MAKE_WRITABLE: /* make writable */ |
| i = vg_alloc_client_block(); |
| vg_cgbs[i].kind = CG_Writable; |
| vg_cgbs[i].start = arg[1]; |
| vg_cgbs[i].size = arg[2]; |
| vg_cgbs[i].where = VG_(get_ExeContext) ( tst ); |
| MC_(make_writable) ( arg[1], arg[2] ); |
| *ret = i; |
| break; |
| |
| case VG_USERREQ__MAKE_READABLE: /* make readable */ |
| i = vg_alloc_client_block(); |
| vg_cgbs[i].kind = CG_Readable; |
| vg_cgbs[i].start = arg[1]; |
| vg_cgbs[i].size = arg[2]; |
| vg_cgbs[i].where = VG_(get_ExeContext) ( tst ); |
| MC_(make_readable) ( arg[1], arg[2] ); |
| *ret = i; |
| break; |
| |
| case VG_USERREQ__DISCARD: /* discard */ |
| if (vg_cgbs == NULL |
| || arg[2] >= vg_cgb_used || vg_cgbs[arg[2]].kind == CG_NotInUse) |
| return 1; |
| sk_assert(arg[2] >= 0 && arg[2] < vg_cgb_used); |
| vg_cgbs[arg[2]].kind = CG_NotInUse; |
| vg_cgb_discards++; |
| *ret = 0; |
| break; |
| |
| default: |
| if (MAC_(handle_common_client_requests)(tst, arg, ret )) { |
| return True; |
| } else { |
| VG_(message)(Vg_UserMsg, |
| "Warning: unknown memcheck client request code %d", |
| arg[0]); |
| return False; |
| } |
| } |
| return True; |
| } |
| |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end mc_clientreqs.c ---*/ |
| /*--------------------------------------------------------------------*/ |