diff options
| -rw-r--r-- | ChangeLog | 10 | ||||
| -rw-r--r-- | elf/dl-error.c | 72 |
2 files changed, 50 insertions, 32 deletions
diff --git a/ChangeLog b/ChangeLog index a19631db42..2d8010ea0d 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2013-12-16 Roland McGrath <roland@hack.frob.com> + + * elf/dl-error.c (struct catch): Add new member `errcode'. Add a + level of indirection to members `objname', `errstring', `malloced'. + (_dl_signal_error): Store through pointers in *LCATCH rather modifying + *LCATCH itself. Set *LCATCH->errcode to ERRCODE rather than passing + it as the __longjmp argument (just pass 1 instead). + (_dl_catch_error): Initialize C with argument pointers and address of + volatile local ERRCODE rather than copying values out of C at return. + 2013-12-16 Joseph Myers <joseph@codesourcery.com> * math/auto-libm-test-in: Add tests of atan2, hypot and pow. diff --git a/elf/dl-error.c b/elf/dl-error.c index 8257c17030..79e3fa38f2 100644 --- a/elf/dl-error.c +++ b/elf/dl-error.c @@ -28,10 +28,11 @@ _dl_signal_error. */ struct catch { - const char *objname; /* Object/File name. */ - const char *errstring; /* Error detail filled in here. */ - bool malloced; /* Nonzero if the string is malloced + const char **objname; /* Object/File name. */ + const char **errstring; /* Error detail filled in here. */ + bool *malloced; /* Nonzero if the string is malloced by the libc malloc. */ + volatile int *errcode; /* Return value of _dl_signal_error. */ jmp_buf env; /* longjmp here on error. */ }; @@ -86,33 +87,36 @@ _dl_signal_error (int errcode, const char *objname, const char *occation, size_t len_objname = strlen (objname) + 1; size_t len_errstring = strlen (errstring) + 1; - lcatch->errstring = (char *) malloc (len_objname + len_errstring); - if (lcatch->errstring != NULL) + char *errstring_copy = malloc (len_objname + len_errstring); + if (errstring_copy != NULL) { /* Make a copy of the object file name and the error string. */ - lcatch->objname = memcpy (__mempcpy ((char *) lcatch->errstring, - errstring, len_errstring), - objname, len_objname); + *lcatch->objname = memcpy (__mempcpy (errstring_copy, + errstring, len_errstring), + objname, len_objname); + *lcatch->errstring = errstring_copy; /* If the main executable is relocated it means the libc's malloc is used. */ + bool malloced = true; #ifdef SHARED - lcatch->malloced = (GL(dl_ns)[LM_ID_BASE]._ns_loaded != NULL - && (GL(dl_ns)[LM_ID_BASE]._ns_loaded->l_relocated - != 0)); -#else - lcatch->malloced = true; + malloced = (GL(dl_ns)[LM_ID_BASE]._ns_loaded != NULL + && (GL(dl_ns)[LM_ID_BASE]._ns_loaded->l_relocated != 0)); #endif + *lcatch->malloced = malloced; } else { /* This is better than nothing. */ - lcatch->objname = ""; - lcatch->errstring = _dl_out_of_memory; - lcatch->malloced = false; + *lcatch->objname = ""; + *lcatch->errstring = _dl_out_of_memory; + *lcatch->malloced = false; } + + *lcatch->errcode = errcode; + /* We do not restore the signal mask because none was saved. */ - __longjmp (lcatch->env[0].__jmpbuf, errcode ?: -1); + __longjmp (lcatch->env[0].__jmpbuf, 1); } else { @@ -157,23 +161,29 @@ internal_function _dl_catch_error (const char **objname, const char **errstring, bool *mallocedp, void (*operate) (void *), void *args) { - int errcode; - struct catch *volatile old; - struct catch c; /* We need not handle `receiver' since setting a `catch' is handled before it. */ - /* Some systems (e.g., SPARC) handle constructors to local variables - inefficient. So we initialize `c' by hand. */ - c.errstring = NULL; + /* Only this needs to be marked volatile, because it is the only local + variable that gets changed between the setjmp invocation and the + longjmp call. All others are just set here (before setjmp) and read + in _dl_signal_error (before longjmp). */ + volatile int errcode; + + struct catch c; + /* Don't use an initializer since we don't need to clear C.env. */ + c.objname = objname; + c.errstring = errstring; + c.malloced = mallocedp; + c.errcode = &errcode; struct catch **const catchp = &CATCH_HOOK; - old = *catchp; + struct catch *const old = *catchp; + *catchp = &c; + /* Do not save the signal mask. */ - errcode = __sigsetjmp (c.env, 0); - if (__builtin_expect (errcode, 0) == 0) + if (__builtin_expect (__sigsetjmp (c.env, 0), 0) == 0) { - *catchp = &c; (*operate) (args); *catchp = old; *objname = NULL; @@ -182,12 +192,10 @@ _dl_catch_error (const char **objname, const char **errstring, return 0; } - /* We get here only if we longjmp'd out of OPERATE. */ + /* We get here only if we longjmp'd out of OPERATE. _dl_signal_error has + already stored values into *OBJNAME, *ERRSTRING, and *MALLOCEDP. */ *catchp = old; - *objname = c.objname; - *errstring = c.errstring; - *mallocedp = c.malloced; - return errcode == -1 ? 0 : errcode; + return errcode; } |