diff options
Diffstat (limited to 'usr/src/lib/libc/port/gen/walkstack.c')
| -rw-r--r-- | usr/src/lib/libc/port/gen/walkstack.c | 53 |
1 files changed, 14 insertions, 39 deletions
diff --git a/usr/src/lib/libc/port/gen/walkstack.c b/usr/src/lib/libc/port/gen/walkstack.c index 9e2d0fcd5f..a4bcef258e 100644 --- a/usr/src/lib/libc/port/gen/walkstack.c +++ b/usr/src/lib/libc/port/gen/walkstack.c @@ -18,7 +18,7 @@ * * CDDL HEADER END * - * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -76,7 +76,7 @@ * The bottom-most struct frame is actually constructed by the kernel by * copying the previous stack frame, allowing naive backtrace code to simply * skip over the interrupted frame. The copied frame is never really used, - * since it is presumed the libc or libthread signal handler wrapper function + * since it is presumed the signal handler wrapper function * will explicitly setcontext(2) to the interrupted context if the user * program's handler returns. If we detect a signal handler frame, we simply * read the interrupted context structure from the stack, use its embedded @@ -96,18 +96,11 @@ * Since we want to provide the signal number that generated a signal stack * frame and on sparc this information isn't written to the stack by the kernel * the way it's done on i386, we're forced to read the signo from the stack as - * one of the arguments to the signal handler. What we hope is that no one has - * used __sigaction directly; if we're not linked with libthread - * (_thr_sighndlrinfo is NULL) then we attempt to read the signo directly from - * the register window. Otherwise we use the _thr_sighndlrinfo interface to find - * the correct frame. - * + * one of the arguments to the signal handler. We use the thr_sighndlrinfo + * interface to find the correct frame. */ -#pragma weak walkcontext = _walkcontext -#pragma weak printstack = _printstack - -#include "synonyms.h" +#include "lint.h" #include <assert.h> #include <dlfcn.h> #include <fcntl.h> @@ -221,11 +214,9 @@ walkcontext(const ucontext_t *uptr, int (*operate_func)(uintptr_t, int, void *), /* * Since we don't write signo to the stack on sparc, we need - * to extract signo from the stack frames. This is problematic - * in the case of libthread (libc has deterministic behavior) - * since we're not sure where we can do that safely. An awkward - * interface was provided for this purpose in libthread: - * _thr_sighndlrinfo; this is documented in + * to extract signo from the stack frames. + * An awkward interface is provided for this purpose: + * thr_sighndlrinfo; this is documented in * /shared/sac/PSARC/1999/024. When called, this function * returns the PC of a special function (and its size) that * will be present in the stack frame if a signal was @@ -235,20 +226,15 @@ walkcontext(const ucontext_t *uptr, int (*operate_func)(uintptr_t, int, void *), * Since this function is written in assembler and doesn't * perturb its registers, we can then read sig out of arg0 * when the saved pc is inside this function. - * */ #if defined(__sparc) uintptr_t special_pc = NULL; int special_size = 0; - extern void _thr_sighndlrinfo(void (**func)(), int *funcsize); - -#pragma weak _thr_sighndlrinfo + extern void thr_sighndlrinfo(void (**func)(), int *funcsize); - if (_thr_sighndlrinfo != NULL) { - _thr_sighndlrinfo((void (**)())&special_pc, &special_size); - } + thr_sighndlrinfo((void (**)())&special_pc, &special_size); #endif /* sparc */ @@ -290,24 +276,14 @@ walkcontext(const ucontext_t *uptr, int (*operate_func)(uintptr_t, int, void *), #if defined(__sparc) /* - * with sparc we need to handle - * single and multi-threaded cases - * separately - * If we're single threaded, the trampoline - * in libc will have the signo as the first - * argumment; we can snag that directly. * In the case of threads, since there are multiple * complex routines between kernel and user handler, * we need to figure out where we can read signal from - * using _thr_sighndlrinfo - which we've already done + * using thr_sighndlrinfo - which we've already done * for this signal, since it appeared on the stack * before the signal frame.... sigh. */ - - if (_thr_sighndlrinfo == NULL) /* single threaded */ - sig = fp->fr_arg[0]; - else - sig = signo; /* already read - see below */ + sig = signo; /* already read - see below */ #endif /* * this is the special signal frame, so cons up @@ -328,8 +304,7 @@ walkcontext(const ucontext_t *uptr, int (*operate_func)(uintptr_t, int, void *), * lookahead code to find right spot to read signo from... */ - if (_thr_sighndlrinfo && - savepc >= special_pc && savepc < + if (savepc >= special_pc && savepc < (special_pc + special_size)) signo = fp->fr_arg[0]; #endif @@ -389,7 +364,7 @@ display_stack_info(uintptr_t pc, int signo, void *arg) (void) sig2str(signo, sigbuf); async_filenoprintf(filenum, "%s [Signal %d (%s)]\n", - buffer, (ulong_t)signo, sigbuf); + buffer, (ulong_t)signo, sigbuf); } else async_filenoprintf(filenum, "%s\n", buffer); |