| /*--------------------------------------------------------------------*/ |
| /*--- Management of function redirection and wrapping. ---*/ |
| /*--- vg_redir.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, an extensible x86 protected-mode |
| emulator for monitoring program execution on x86-Unixes. |
| |
| Copyright (C) 2000-2005 Julian Seward |
| jseward@acm.org |
| Copyright (C) 2003-2005 Jeremy Fitzhardinge |
| jeremy@goop.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 "pub_core_basics.h" |
| #include "pub_core_threadstate.h" // needed for pub_core_main.h |
| #include "pub_core_aspacemgr.h" |
| #include "pub_core_libcbase.h" |
| #include "pub_core_libcassert.h" |
| #include "pub_core_libcprint.h" |
| #include "pub_core_main.h" // for VG_(set_libc_freeres_wrapper_addr) |
| #include "pub_core_mallocfree.h" |
| #include "pub_core_options.h" |
| #include "pub_core_redir.h" |
| #include "pub_core_skiplist.h" |
| #include "pub_core_trampoline.h" |
| #include "pub_core_transtab.h" |
| #include "m_debuginfo/priv_symtab.h" // XXX: bad! |
| |
| /*------------------------------------------------------------*/ |
| /*--- General purpose redirection. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* |
| wraps and redirections, indexed by from_addr |
| |
| Redirection and wrapping are two distinct mechanisms which Valgrind |
| can use to change the client's control flow. |
| |
| Redirection intercepts a call to a client function, and re-points it |
| to a new piece of code (presumably functionally equivalent). The |
| original code is never run. |
| |
| Wrapping does call the client's original code, but calls "before" |
| and "after" functions which can inspect (and perhaps modify) the |
| function's arguments and return value. |
| */ |
| struct _CodeRedirect { |
| enum redir_type { |
| R_REDIRECT, /* plain redirection */ |
| R_WRAPPER, /* wrap with valgrind-internal code */ |
| R_CLIENT_WRAPPER, /* wrap with client-side code */ |
| } type; |
| |
| const Char *from_lib; /* library qualifier pattern */ |
| const Char *from_sym; /* symbol */ |
| Addr from_addr; /* old addr */ |
| |
| /* used for redirection */ |
| const Char *to_lib; /* library qualifier pattern */ |
| const Char *to_sym; /* symbol */ |
| Addr to_addr; /* new addr */ |
| |
| /* used for wrapping */ |
| const FuncWrapper *wrapper; |
| |
| CodeRedirect *next; /* next pointer on unresolved list */ |
| }; |
| |
| static Char *straddr(void *p) |
| { |
| static Char buf[16]; |
| |
| VG_(sprintf)(buf, "%p", *(Addr *)p); |
| |
| return buf; |
| } |
| |
| static SkipList sk_resolved_redir = VG_SKIPLIST_INIT(CodeRedirect, from_addr, |
| VG_(cmp_Addr), straddr, VG_AR_SYMTAB); |
| static CodeRedirect *unresolved_redir = NULL; |
| |
| static Bool match_lib(const Char *pattern, const SegInfo *si) |
| { |
| /* pattern == NULL matches everything, otherwise use globbing |
| |
| If the pattern starts with: |
| file:, then match filename |
| soname:, then match soname |
| something else, match filename |
| */ |
| const Char *name = si->filename; |
| |
| if (pattern == NULL) |
| return True; |
| |
| if (VG_(strncmp)(pattern, "file:", 5) == 0) { |
| pattern += 5; |
| name = si->filename; |
| } |
| if (VG_(strncmp)(pattern, "soname:", 7) == 0) { |
| pattern += 7; |
| name = si->soname; |
| } |
| |
| if (name == NULL) |
| return False; |
| |
| return VG_(string_match)(pattern, name); |
| } |
| |
| static inline Bool from_resolved(const CodeRedirect *redir) |
| { |
| return redir->from_addr != 0; |
| } |
| |
| static inline Bool to_resolved(const CodeRedirect *redir) |
| { |
| if (redir->type == R_REDIRECT) |
| return redir->to_addr != 0; |
| vg_assert(redir->wrapper != NULL); |
| return True; |
| } |
| |
| Bool VG_(is_resolved)(const CodeRedirect *redir) |
| { |
| return from_resolved(redir) && to_resolved(redir); |
| } |
| |
| static void add_resolved(CodeRedirect *redir) |
| { |
| switch(redir->type) { |
| case R_REDIRECT: |
| if (VG_(clo_trace_redir)) { |
| VG_(message)(Vg_DebugMsg, " redir resolved (%s:%s=%p -> ", |
| redir->from_lib, redir->from_sym, redir->from_addr); |
| VG_(message)(Vg_DebugMsg, " %s:%s=%p)", |
| redir->to_lib, redir->to_sym, redir->to_addr); |
| } |
| |
| if (VG_(search_transtab)(NULL, (Addr64)redir->from_addr, False)) { |
| /* For some given (from, to) redir, the "from" function got |
| called before the .so containing "to" became available. We |
| know this because there is already a translation for the |
| entry point of the original "from". So the redirect will |
| never actually take effect unless that translation is |
| discarded. |
| |
| Note, we only really need to discard the first bb of the |
| old entry point, and so we avoid the problem of having to |
| figure out how big that bb was -- since it is at least 1 |
| byte of original code, we can just pass 1 as the original |
| size to invalidate_translations() and it will indeed get |
| rid of the translation. |
| |
| Note, this is potentially expensive -- discarding |
| translations causes complete unchaining. |
| */ |
| if (VG_(clo_verbosity) > 2 && VG_(clo_trace_redir)) { |
| VG_(message)(Vg_UserMsg, |
| "Discarding translation due to redirect of already called function" ); |
| VG_(message)(Vg_UserMsg, |
| " %s (%p -> %p)", |
| redir->from_sym, redir->from_addr, redir->to_addr ); |
| } |
| VG_(discard_translations)((Addr64)redir->from_addr, 1); |
| } |
| |
| { |
| CodeRedirect *r = VG_(SkipList_Find_Exact)(&sk_resolved_redir, &redir->from_addr); |
| |
| if (r == NULL) |
| VG_(SkipList_Insert)(&sk_resolved_redir, redir); |
| else { |
| /* XXX leak redir */ |
| if (VG_(clo_trace_redir)) |
| VG_(message)(Vg_DebugMsg, " redir %s:%s:%p->%s:%s:%p duplicated\n", |
| redir->from_lib, redir->from_sym, redir->from_addr, |
| redir->to_lib, redir->to_sym, redir->to_addr); |
| } |
| } |
| break; |
| |
| case R_WRAPPER: |
| if (VG_(clo_trace_redir)) { |
| VG_(message)(Vg_DebugMsg, " wrapper resolved (%s:%s=%p -> wrapper)", |
| redir->from_lib, redir->from_sym, redir->from_addr); |
| } |
| |
| /* XXX redir leaked */ |
| //VG_(wrap_function)(redir->from_addr, redir->wrapper); |
| break; |
| |
| case R_CLIENT_WRAPPER: |
| VG_(core_panic)("not implemented"); |
| break; |
| } |
| } |
| |
| /* Resolve a redir using si if possible, and add it to the resolved |
| list */ |
| static Bool resolve_redir(CodeRedirect *redir, const SegInfo *si) |
| { |
| Bool resolved; |
| |
| vg_assert(si != NULL); |
| vg_assert(si->seg != NULL); |
| |
| /* no redirection from Valgrind segments */ |
| if (si->seg->flags & SF_VALGRIND) |
| return False; |
| |
| resolved = VG_(is_resolved)(redir); |
| |
| if (0 && VG_(clo_trace_redir)) |
| VG_(printf)(" consider FROM binding %s:%s -> %s:%s in %s(%s)\n", |
| redir->from_lib, redir->from_sym, |
| redir->to_lib, redir->to_sym, |
| si->filename, si->soname); |
| |
| vg_assert(!resolved); |
| |
| if (!from_resolved(redir)) { |
| vg_assert(redir->from_sym != NULL); |
| |
| if (match_lib(redir->from_lib, si)) { |
| redir->from_addr = VG_(reverse_search_one_symtab)(si, redir->from_sym); |
| if (VG_(clo_trace_redir) && redir->from_addr != 0) |
| VG_(printf)(" bind FROM: %p = %s:%s\n", |
| redir->from_addr,redir->from_lib, redir->from_sym ); |
| } |
| } |
| |
| if (!to_resolved(redir)) { |
| vg_assert(redir->type == R_REDIRECT); |
| vg_assert(redir->to_sym != NULL); |
| |
| if (match_lib(redir->to_lib, si)) { |
| redir->to_addr = VG_(reverse_search_one_symtab)(si, redir->to_sym); |
| if (VG_(clo_trace_redir) && redir->to_addr != 0) |
| VG_(printf)(" bind TO: %p = %s:%s\n", |
| redir->to_addr,redir->to_lib, redir->to_sym ); |
| |
| } |
| } |
| |
| resolved = from_resolved(redir) && to_resolved(redir); |
| |
| if (0 && VG_(clo_trace_redir)) |
| VG_(printf)("resolve_redir: %s:%s from=%p %s:%s to=%p\n", |
| redir->from_lib, redir->from_sym, redir->from_addr, |
| redir->to_lib, redir->to_sym, redir->to_addr); |
| |
| if (resolved) add_resolved(redir); |
| |
| return resolved; |
| } |
| |
| static Bool resolve_redir_allsegs(CodeRedirect *redir) |
| { |
| const SegInfo *si; |
| |
| for(si = VG_(next_seginfo)(NULL); |
| si != NULL; |
| si = VG_(next_seginfo)(si)) |
| { |
| if (resolve_redir(redir, si)) |
| return True; |
| } |
| return False; |
| } |
| |
| /* Go through the complete redir list, resolving as much as possible with this SegInfo. |
| |
| This should be called when a new SegInfo symtab is loaded. |
| */ |
| void VG_(resolve_seg_redirs)(SegInfo *si) |
| { |
| CodeRedirect **prevp = &unresolved_redir; |
| CodeRedirect *redir, *next; |
| |
| if (VG_(clo_trace_redir)) |
| VG_(printf)("Considering redirs to/from %s(soname=%s)\n", |
| si->filename, si->soname); |
| |
| /* visit each unresolved redir - if it becomes resolved, then |
| remove it from the unresolved list */ |
| for(redir = unresolved_redir; redir != NULL; redir = next) { |
| next = redir->next; |
| |
| if (resolve_redir(redir, si)) { |
| *prevp = next; |
| redir->next = NULL; |
| } else |
| prevp = &redir->next; |
| } |
| } |
| |
| static void add_redirect_X_to_X( |
| const Char *from_lib, const Char *from_sym, Addr from_addr, |
| const Char *to_lib, const Char *to_sym, Addr to_addr |
| ) |
| { |
| CodeRedirect *redir = VG_(SkipNode_Alloc)(&sk_resolved_redir); |
| |
| redir->type = R_REDIRECT; |
| |
| if (from_lib) redir->from_lib = VG_(arena_strdup)(VG_AR_SYMTAB, from_lib); |
| else redir->from_lib = NULL; |
| if (from_sym) redir->from_sym = VG_(arena_strdup)(VG_AR_SYMTAB, from_sym); |
| else redir->from_sym = NULL; |
| redir->from_addr = from_addr; |
| |
| if (to_lib) redir->to_lib = VG_(arena_strdup)(VG_AR_SYMTAB, to_lib); |
| else redir->to_lib = NULL; |
| if (to_sym) redir->to_sym = VG_(arena_strdup)(VG_AR_SYMTAB, to_sym); |
| else redir->to_sym = NULL; |
| redir->to_addr = to_addr; |
| |
| if (VG_(clo_verbosity) >= 2 && VG_(clo_trace_redir)) |
| VG_(message)(Vg_UserMsg, |
| "REDIRECT %s:%s(%p) to %s:%s(%p)", |
| from_lib, from_sym, from_addr, to_lib, to_sym, to_addr); |
| |
| /* Check against all existing segments to see if this redirection |
| can be resolved immediately */ |
| if (VG_(is_resolved)(redir)) { |
| add_resolved(redir); |
| } |
| else if (!resolve_redir_allsegs(redir)) { |
| /* nope, add to list */ |
| redir->next = unresolved_redir; |
| unresolved_redir = redir; |
| } |
| } |
| |
| /* Redirect a lib/symbol reference to a function at lib/symbol */ |
| __attribute__((unused)) |
| static void add_redirect_sym_to_sym(const Char *from_lib, const Char *from_sym, |
| const Char *to_lib, const Char *to_sym) |
| { |
| add_redirect_X_to_X(from_lib, from_sym, 0, to_lib, to_sym, 0); |
| } |
| |
| /* Redirect a lib/symbol reference to a function at addr */ |
| static void add_redirect_sym_to_addr(const Char *from_lib, const Char *from_sym, |
| Addr to_addr) |
| { |
| add_redirect_X_to_X(from_lib, from_sym, 0, NULL, NULL, to_addr); |
| } |
| |
| /* Redirect a function at from_addr to a function at to_addr */ |
| __attribute__((unused)) // It is used, but not on all platforms... |
| static void add_redirect_addr_to_addr(Addr from_addr, Addr to_addr) |
| { |
| add_redirect_X_to_X(NULL, NULL, from_addr, NULL, NULL, to_addr); |
| } |
| |
| CodeRedirect *VG_(add_wrapper)(const Char *from_lib, const Char *from_sym, |
| const FuncWrapper *wrapper) |
| { |
| CodeRedirect *redir = VG_(SkipNode_Alloc)(&sk_resolved_redir); |
| |
| if (0) |
| VG_(printf)("adding wrapper for %s:%s -> (%p,%p)\n", |
| from_lib, from_sym, wrapper->before, wrapper->after); |
| |
| redir->type = R_WRAPPER; |
| |
| redir->from_lib = VG_(arena_strdup)(VG_AR_SYMTAB, from_lib); |
| redir->from_sym = VG_(arena_strdup)(VG_AR_SYMTAB, from_sym); |
| redir->from_addr = 0; |
| |
| redir->to_lib = NULL; |
| redir->to_sym = NULL; |
| redir->to_addr = 0; |
| |
| redir->wrapper = wrapper; |
| |
| /* Check against all existing segments to see if this redirection |
| can be resolved immediately */ |
| if (!resolve_redir_allsegs(redir)) { |
| /* nope, add to list */ |
| redir->next = unresolved_redir; |
| unresolved_redir = redir; |
| } |
| |
| return redir; |
| } |
| |
| /* If address 'a' is being redirected, return the redirected-to |
| address. */ |
| Addr VG_(code_redirect)(Addr a) |
| { |
| CodeRedirect* r; |
| |
| r = VG_(SkipList_Find_Exact)(&sk_resolved_redir, &a); |
| if (r == NULL) |
| return a; |
| |
| vg_assert(r->to_addr != 0); |
| |
| return r->to_addr; |
| } |
| |
| void VG_(setup_code_redirect_table) ( void ) |
| { |
| #if defined(VGP_x86_linux) |
| /* Redirect _dl_sysinfo_int80, which is glibc's default system call |
| routine, to the routine in our trampoline page so that the |
| special sysinfo unwind hack in m_stacktrace.c will kick in. */ |
| add_redirect_sym_to_addr("soname:ld-linux.so.2", "_dl_sysinfo_int80", |
| VG_(client_trampoline_code)+VG_(tramp_syscall_offset)); |
| #elif defined(VGP_amd64_linux) |
| /* Redirect vsyscalls to local versions */ |
| add_redirect_addr_to_addr(0xFFFFFFFFFF600000ULL, |
| VG_(client_trampoline_code)+VG_(tramp_gettimeofday_offset)); |
| add_redirect_addr_to_addr(0xFFFFFFFFFF600400ULL, |
| VG_(client_trampoline_code)+VG_(tramp_time_offset)); |
| #else |
| # error Unknown platform |
| #endif |
| } |
| |
| /* Z-decode a symbol into library:func form, eg |
| |
| _vgi_libcZdsoZd6__ZdlPv --> libc.so.6:_ZdlPv |
| |
| Uses the Z-encoding scheme described in pub_core_redir.h. |
| Returns True if demangle OK, False otherwise. |
| */ |
| static Bool Z_decode(const Char* symbol, Char* result, Int nbytes) |
| { |
| # define EMIT(ch) \ |
| do { \ |
| if (j >= nbytes) \ |
| result[j-1] = 0; \ |
| else \ |
| result[j++] = ch; \ |
| } while (0) |
| |
| Bool error = False; |
| Int i, j = 0; |
| Int len = VG_(strlen)(symbol); |
| if (0) VG_(printf)("idm: %s\n", symbol); |
| |
| i = VG_REPLACE_FUNCTION_PREFIX_LEN; |
| |
| /* Chew though the Z-encoded soname part. */ |
| while (True) { |
| |
| if (i >= len) |
| break; |
| |
| if (symbol[i] == '_') |
| /* We found the underscore following the Z-encoded soname. |
| Just copy the rest literally. */ |
| break; |
| |
| if (symbol[i] != 'Z') { |
| EMIT(symbol[i]); |
| i++; |
| continue; |
| } |
| |
| /* We've got a Z-escape. Act accordingly. */ |
| i++; |
| if (i >= len) { |
| /* Hmm, Z right at the end. Something's wrong. */ |
| error = True; |
| EMIT('Z'); |
| break; |
| } |
| switch (symbol[i]) { |
| case 'a': EMIT('*'); break; |
| case 'p': EMIT('+'); break; |
| case 'c': EMIT(':'); break; |
| case 'd': EMIT('.'); break; |
| case 'u': EMIT('_'); break; |
| case 'h': EMIT('-'); break; |
| case 's': EMIT(' '); break; |
| case 'Z': EMIT('Z'); break; |
| default: error = True; EMIT('Z'); EMIT(symbol[i]); break; |
| } |
| i++; |
| } |
| |
| if (error || i >= len || symbol[i] != '_') { |
| /* Something's wrong. Give up. */ |
| VG_(message)(Vg_UserMsg, "intercept: error demangling: %s", symbol); |
| EMIT(0); |
| return False; |
| } |
| |
| /* Copy the rest of the string verbatim. */ |
| i++; |
| EMIT(':'); |
| while (True) { |
| if (i >= len) |
| break; |
| EMIT(symbol[i]); |
| i++; |
| } |
| |
| EMIT(0); |
| if (0) VG_(printf)("%s\n", result); |
| return True; |
| |
| # undef EMIT |
| } |
| |
| // Nb: this can change the string pointed to by 'symbol'. |
| static void handle_replacement_function( Char* symbol, Addr addr ) |
| { |
| Bool ok; |
| Int len = VG_(strlen)(symbol) + 1 - VG_REPLACE_FUNCTION_PREFIX_LEN; |
| Char *lib = VG_(arena_malloc)(VG_AR_SYMTAB, len+8); |
| Char *func; |
| |
| // Put "soname:" at the start of lib |
| VG_(strcpy)(lib, "soname:"); |
| |
| ok = Z_decode(symbol, lib+7, len); |
| if (ok) { |
| // lib is "soname:<libname>:<fnname>". Split the string at the 2nd ':'. |
| func = lib + VG_(strlen)(lib)-1; |
| while(*func != ':') func--; |
| *func = '\0'; |
| func++; // Move past the '\0' |
| |
| // Now lib is "soname:<libname>" and func is "<fnname>". |
| if (0) VG_(printf)("lib A%sZ, func A%sZ\n", lib, func); |
| add_redirect_sym_to_addr(lib, func, addr); |
| |
| // Overwrite the given Z-encoded name with just the fnname. |
| VG_(strcpy)(symbol, func); |
| } |
| |
| VG_(arena_free)(VG_AR_SYMTAB, lib); |
| } |
| |
| // This is specifically for stringifying VG_(x) function names. We |
| // need to do two macroexpansions to get the VG_ macro expanded before |
| // stringifying. |
| #define _STR(x) #x |
| #define STR(x) _STR(x) |
| |
| static void handle_load_notifier( Char* symbol, Addr addr ) |
| { |
| if (VG_(strcmp)(symbol, STR(VG_NOTIFY_ON_LOAD(freeres))) == 0) |
| VG_(set_libc_freeres_wrapper_addr)(addr); |
| // else if (VG_(strcmp)(symbol, STR(VG_WRAPPER(pthread_startfunc_wrapper))) == 0) |
| // VG_(pthread_startfunc_wrapper)((Addr)(si->offset + sym->st_value)); |
| else |
| vg_assert2(0, "unrecognised load notification function: %s", symbol); |
| } |
| |
| static Bool is_replacement_function(Char* s) |
| { |
| return (0 == VG_(strncmp)(s, |
| VG_REPLACE_FUNCTION_PREFIX, |
| VG_REPLACE_FUNCTION_PREFIX_LEN)); |
| } |
| |
| static Bool is_load_notifier(Char* s) |
| { |
| return (0 == VG_(strncmp)(s, |
| VG_NOTIFY_ON_LOAD_PREFIX, |
| VG_NOTIFY_ON_LOAD_PREFIX_LEN)); |
| } |
| |
| // Call this for each symbol loaded. It determines if we need to do |
| // anything special with it. It can modify 'symbol' in-place. |
| void VG_(maybe_redir_or_notify) ( Char* symbol, Addr addr ) |
| { |
| if (is_replacement_function(symbol)) |
| handle_replacement_function(symbol, addr); |
| else |
| if (is_load_notifier(symbol)) |
| handle_load_notifier(symbol, addr); |
| } |
| |
| |
| //:: /*------------------------------------------------------------*/ |
| //:: /*--- General function wrapping. ---*/ |
| //:: /*------------------------------------------------------------*/ |
| //:: |
| //:: /* |
| //:: TODO: |
| //:: - hook into the symtab machinery |
| //:: - client-side wrappers? |
| //:: - better interfaces for before() functions to get to arguments |
| //:: - handle munmap of code (dlclose()) |
| //:: - handle thread exit |
| //:: - handle longjmp |
| //:: */ |
| //:: struct callkey { |
| //:: ThreadId tid; /* calling thread */ |
| //:: Addr esp; /* address of args on stack */ |
| //:: Addr eip; /* return address */ |
| //:: }; |
| //:: |
| //:: struct call_instance { |
| //:: struct callkey key; |
| //:: |
| //:: const FuncWrapper *wrapper; |
| //:: void *nonce; |
| //:: }; |
| //:: |
| //:: static inline Addr addrcmp(Addr a, Addr b) |
| //:: { |
| //:: if (a < b) |
| //:: return -1; |
| //:: else if (a > b) |
| //:: return 1; |
| //:: else |
| //:: return 0; |
| //:: } |
| //:: |
| //:: static inline Int cmp(UInt a, UInt b) |
| //:: { |
| //:: if (a < b) |
| //:: return -1; |
| //:: else if (a > b) |
| //:: return 1; |
| //:: else |
| //:: return 0; |
| //:: } |
| //:: |
| //:: static Int keycmp(const void *pa, const void *pb) |
| //:: { |
| //:: const struct callkey *a = (const struct callkey *)pa; |
| //:: const struct callkey *b = (const struct callkey *)pb; |
| //:: Int ret; |
| //:: |
| //:: if ((ret = cmp(a->tid, b->tid))) |
| //:: return ret; |
| //:: |
| //:: if ((ret = addrcmp(a->esp, b->esp))) |
| //:: return ret; |
| //:: |
| //:: return addrcmp(a->eip, b->eip); |
| //:: } |
| //:: |
| //:: /* List of wrapped call invocations which are currently active */ |
| //:: static SkipList wrapped_frames = VG_SKIPLIST_INIT(struct call_instance, key, keycmp, |
| //:: NULL, VG_AR_SYMTAB); |
| //:: |
| //:: static struct call_instance *find_call(Addr retaddr, Addr argsp, ThreadId tid) |
| //:: { |
| //:: struct callkey key = { tid, argsp, retaddr }; |
| //:: |
| //:: return VG_(SkipList_Find_Exact)(&wrapped_frames, &key); |
| //:: } |
| //:: |
| //:: static void wrapper_return(Addr retaddr); |
| //:: |
| //:: /* Called from generated code via helper */ |
| //:: void VG_(wrap_before)(ThreadState *tst, const FuncWrapper *wrapper) |
| //:: { |
| //:: Addr retaddr = VGA_RETADDR(tst->arch); |
| //:: Addr argp = (Addr)&VGA_FUNC_ARG(tst->arch, 0); |
| //:: void *nonce = NULL; |
| //:: Bool mf = VG_(my_fault); |
| //:: VG_(my_fault) = True; |
| //:: |
| //:: if (wrapper->before) { |
| //:: va_list args = VGA_VA_LIST(tst->arch); |
| //:: nonce = (*wrapper->before)(args); |
| //:: } |
| //:: |
| //:: if (wrapper->after) { |
| //:: /* If there's an after function, make sure it gets called */ |
| //:: struct call_instance *call; |
| //:: |
| //:: call = find_call(retaddr, argp, tst->tid); |
| //:: |
| //:: if (call != NULL) { |
| //:: /* Found a stale outstanding call; clean it up and recycle |
| //:: the structure */ |
| //:: if (call->wrapper->after) |
| //:: (*call->wrapper->after)(call->nonce, RT_LONGJMP, 0); |
| //:: } else { |
| //:: call = VG_(SkipNode_Alloc)(&wrapped_frames); |
| //:: |
| //:: call->key.tid = tst->tid; |
| //:: call->key.esp = argp; |
| //:: call->key.eip = retaddr; |
| //:: |
| //:: VG_(SkipList_Insert)(&wrapped_frames, call); |
| //:: |
| //:: wrapper_return(retaddr); |
| //:: } |
| //:: |
| //:: call->wrapper = wrapper; |
| //:: call->nonce = nonce; |
| //:: } else |
| //:: vg_assert(nonce == NULL); |
| //:: |
| //:: VG_(my_fault) = mf; |
| //:: } |
| //:: |
| //:: /* Called from generated code via helper */ |
| //:: void VG_(wrap_after)(ThreadState *tst) |
| //:: { |
| //:: Addr EIP = VGA_INSTR_PTR(tst->arch); /* instruction after call */ |
| //:: Addr ESP = VGA_STACK_PTR(tst->arch); /* pointer to args */ |
| //:: Word ret = VGA_RETVAL(tst->arch); /* return value */ |
| //:: struct call_instance *call; |
| //:: Bool mf = VG_(my_fault); |
| //:: |
| //:: VG_(my_fault) = True; |
| //:: call = find_call(EIP, ESP, tst->tid); |
| //:: |
| //:: if (0) |
| //:: VG_(printf)("wrap_after(%p,%p,%d) -> %p\n", EIP, ESP, tst->tid, call); |
| //:: |
| //:: if (call != NULL) { |
| //:: if (call->wrapper->after) |
| //:: (*call->wrapper->after)(call->nonce, RT_RETURN, ret); |
| //:: |
| //:: VG_(SkipList_Remove)(&wrapped_frames, &call->key); |
| //:: VG_(SkipNode_Free)(&wrapped_frames, call); |
| //:: } |
| //:: VG_(my_fault) = mf; |
| //:: } |
| //:: |
| //:: |
| //:: struct wrapped_function { |
| //:: Addr eip; /* eip of function entrypoint */ |
| //:: const FuncWrapper *wrapper; |
| //:: }; |
| //:: |
| //:: struct wrapper_return { |
| //:: Addr eip; /* return address */ |
| //:: }; |
| //:: |
| //:: /* A mapping from eip of wrapped function entrypoints to actual wrappers */ |
| //:: static SkipList wrapped_functions = VG_SKIPLIST_INIT(struct wrapped_function, eip, VG_(cmp_Addr), |
| //:: NULL, VG_AR_SYMTAB); |
| //:: |
| //:: /* A set of EIPs which are return addresses for wrapped functions */ |
| //:: static SkipList wrapper_returns = VG_SKIPLIST_INIT(struct wrapper_return, eip, VG_(cmp_Addr), |
| //:: NULL, VG_AR_SYMTAB); |
| //:: |
| //:: /* Wrap function starting at eip */ |
| //:: void VG_(wrap_function)(Addr eip, const FuncWrapper *wrapper) |
| //:: { |
| //:: struct wrapped_function *func; |
| //:: |
| //:: if (0) |
| //:: VG_(printf)("wrapping %p with (%p,%p)\n", eip, wrapper->before, wrapper->after); |
| //:: |
| //:: func = VG_(SkipList_Find_Exact)(&wrapped_functions, &eip); |
| //:: |
| //:: if (func == NULL) { |
| //:: func = VG_(SkipNode_Alloc)(&wrapped_functions); |
| //:: VG_(invalidate_translations)(eip, 1, True); |
| //:: |
| //:: func->eip = eip; |
| //:: VG_(SkipList_Insert)(&wrapped_functions, func); |
| //:: } |
| //:: |
| //:: func->wrapper = wrapper; |
| //:: } |
| //:: |
| //:: const FuncWrapper *VG_(is_wrapped)(Addr eip) |
| //:: { |
| //:: struct wrapped_function *func = VG_(SkipList_Find_Exact)(&wrapped_functions, &eip); |
| //:: |
| //:: if (func) |
| //:: return func->wrapper; |
| //:: return NULL; |
| //:: } |
| //:: |
| //:: Bool VG_(is_wrapper_return)(Addr eip) |
| //:: { |
| //:: struct wrapper_return *ret = VG_(SkipList_Find_Exact)(&wrapper_returns, &eip); |
| //:: |
| //:: return ret != NULL; |
| //:: } |
| //:: |
| //:: /* Mark eip as being the return address of a wrapper, so that the |
| //:: codegen will generate the appropriate call. */ |
| //:: void wrapper_return(Addr eip) |
| //:: { |
| //:: struct wrapper_return *ret; |
| //:: |
| //:: if (VG_(is_wrapper_return)(eip)) |
| //:: return; |
| //:: |
| //:: VG_(invalidate_translations)(eip, 1, True); |
| //:: |
| //:: ret = VG_(SkipNode_Alloc)(&wrapper_returns); |
| //:: ret->eip = eip; |
| //:: |
| //:: VG_(SkipList_Insert)(&wrapper_returns, ret); |
| //:: } |