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coffeecatch.c
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/* CoffeeCatch, a tiny native signal handler/catcher for JNI code.
* (especially for Android/Dalvik)
*
* Copyright (c) 2013, Xavier Roche (http://www.httrack.com/)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef __ANDROID__
#define USE_UNWIND
#define USE_CORKSCREW
#define USE_LIBUNWIND
#endif
/* #undef NO_USE_SIGALTSTACK */
/* #undef USE_SILENT_SIGALTSTACK */
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <assert.h>
#include <signal.h>
#include <setjmp.h>
#if defined(__ANDROID__) && !defined(__BIONIC_HAVE_UCONTEXT_T) && \
defined(__arm__) && !defined(__BIONIC_HAVE_STRUCT_SIGCONTEXT)
#include <asm/sigcontext.h>
#endif
#if (defined(USE_UNWIND) && !defined(USE_CORKSCREW))
#include <unwind.h>
#endif
#include <pthread.h>
#include <dlfcn.h>
#include "coffeecatch.h"
/*#define NDK_DEBUG 1*/
#if ( defined(NDK_DEBUG) && ( NDK_DEBUG == 1 ) )
#define DEBUG(A) do { A; } while(0)
#define FD_ERRNO 2
static void print(const char *const s) {
size_t count;
for(count = 0; s[count] != '\0'; count++) ;
/* write() is async-signal-safe. */
(void) write(FD_ERRNO, s, count);
}
#else
#define DEBUG(A)
#endif
/* Alternative stack size. */
#define SIG_STACK_BUFFER_SIZE SIGSTKSZ
#ifdef USE_UNWIND
/* Number of backtraces to get. */
#define BACKTRACE_FRAMES_MAX 32
#endif
/* Signals to be caught. */
#define SIG_CATCH_COUNT 7
static const int native_sig_catch[SIG_CATCH_COUNT + 1]
= { SIGABRT, SIGILL, SIGTRAP, SIGBUS, SIGFPE, SIGSEGV
#ifdef SIGSTKFLT
, SIGSTKFLT
#endif
, 0 };
/* Maximum value of a caught signal. */
#define SIG_NUMBER_MAX 32
#if defined(__ANDROID__)
#ifndef ucontext_h_seen
#define ucontext_h_seen
/* stack_t definition */
#include <asm/signal.h>
#if defined(__arm__)
/* Taken from richard.quirk's header file. (Android does not have it) */
#if !defined(__BIONIC_HAVE_UCONTEXT_T)
typedef struct ucontext {
unsigned long uc_flags;
struct ucontext *uc_link;
stack_t uc_stack;
struct sigcontext uc_mcontext;
unsigned long uc_sigmask;
} ucontext_t;
#endif
#elif defined(__aarch64__)
#elif defined(__i386__)
#elif defined(__x86_64__)
#if !defined(__BIONIC_HAVE_UCONTEXT_T)
/* Taken from Google Breakpad. */
/* 80-bit floating-point register */
struct _libc_fpreg {
unsigned short significand[4];
unsigned short exponent;
};
/* Simple floating-point state, see FNSTENV instruction */
struct _libc_fpstate {
unsigned long cw;
unsigned long sw;
unsigned long tag;
unsigned long ipoff;
unsigned long cssel;
unsigned long dataoff;
unsigned long datasel;
struct _libc_fpreg _st[8];
unsigned long status;
};
typedef uint32_t greg_t;
typedef struct {
uint32_t gregs[19];
struct _libc_fpstate* fpregs;
uint32_t oldmask;
uint32_t cr2;
} mcontext_t;
enum {
REG_GS = 0,
REG_FS,
REG_ES,
REG_DS,
REG_EDI,
REG_ESI,
REG_EBP,
REG_ESP,
REG_EBX,
REG_EDX,
REG_ECX,
REG_EAX,
REG_TRAPNO,
REG_ERR,
REG_EIP,
REG_CS,
REG_EFL,
REG_UESP,
REG_SS,
};
typedef struct ucontext {
uint32_t uc_flags;
struct ucontext* uc_link;
stack_t uc_stack;
mcontext_t uc_mcontext;
} ucontext_t;
#endif
#elif defined(__mips__)
/* Taken from Google Breakpad. */
typedef struct {
uint32_t regmask;
uint32_t status;
uint64_t pc;
uint64_t gregs[32];
uint64_t fpregs[32];
uint32_t acx;
uint32_t fpc_csr;
uint32_t fpc_eir;
uint32_t used_math;
uint32_t dsp;
uint64_t mdhi;
uint64_t mdlo;
uint32_t hi1;
uint32_t lo1;
uint32_t hi2;
uint32_t lo2;
uint32_t hi3;
uint32_t lo3;
} mcontext_t;
#if !defined(__BIONIC_HAVE_UCONTEXT_T)
typedef struct ucontext {
uint32_t uc_flags;
struct ucontext* uc_link;
stack_t uc_stack;
mcontext_t uc_mcontext;
} ucontext_t;
#endif
#else
#error "Architecture is not supported (unknown ucontext layout)"
#endif
#endif
#ifdef USE_CORKSCREW
typedef struct map_info_t map_info_t;
/* Extracted from Android's include/corkscrew/backtrace.h */
typedef struct {
uintptr_t absolute_pc;
uintptr_t stack_top;
size_t stack_size;
} backtrace_frame_t;
typedef struct {
uintptr_t relative_pc;
uintptr_t relative_symbol_addr;
char* map_name;
char* symbol_name;
char* demangled_name;
} backtrace_symbol_t;
/* Extracted from Android's libcorkscrew/arch-arm/backtrace-arm.c */
typedef ssize_t (*t_unwind_backtrace_signal_arch)
(siginfo_t* si, void* sc, const map_info_t* lst, backtrace_frame_t* bt,
size_t ignore_depth, size_t max_depth);
typedef map_info_t* (*t_acquire_my_map_info_list)();
typedef void (*t_release_my_map_info_list)(map_info_t* milist);
typedef void (*t_get_backtrace_symbols)(const backtrace_frame_t* backtrace,
size_t frames,
backtrace_symbol_t* symbols);
typedef void (*t_free_backtrace_symbols)(backtrace_symbol_t* symbols,
size_t frames);
#endif
#endif
/* Process-wide crash handler structure. */
typedef struct native_code_global_struct {
/* Initialized. */
int initialized;
/* Lock. */
pthread_mutex_t mutex;
/* Backup of sigaction. */
struct sigaction *sa_old;
} native_code_global_struct;
#define NATIVE_CODE_GLOBAL_INITIALIZER { 0, PTHREAD_MUTEX_INITIALIZER, NULL }
/* Thread-specific crash handler structure. */
typedef struct native_code_handler_struct {
/* Restore point context. */
sigjmp_buf ctx;
int ctx_is_set;
int reenter;
/* Alternate stack. */
char *stack_buffer;
size_t stack_buffer_size;
stack_t stack_old;
/* Signal code and info. */
int code;
siginfo_t si;
ucontext_t uc;
/* Uwind context. */
#if (defined(USE_CORKSCREW))
backtrace_frame_t frames[BACKTRACE_FRAMES_MAX];
#elif (defined(USE_UNWIND))
uintptr_t frames[BACKTRACE_FRAMES_MAX];
#endif
#ifdef USE_LIBUNWIND
void* uframes[BACKTRACE_FRAMES_MAX];
#endif
size_t frames_size;
size_t frames_skip;
/* Custom assertion failures. */
const char *expression;
const char *file;
int line;
/* Alarm was fired. */
int alarm;
} native_code_handler_struct;
/* Global crash handler structure. */
static native_code_global_struct native_code_g =
NATIVE_CODE_GLOBAL_INITIALIZER;
/* Thread variable holding context. */
pthread_key_t native_code_thread;
#if (defined(USE_UNWIND) && !defined(USE_CORKSCREW))
/* Unwind callback */
static _Unwind_Reason_Code
coffeecatch_unwind_callback(struct _Unwind_Context* context, void* arg) {
native_code_handler_struct *const s = (native_code_handler_struct*) arg;
const uintptr_t ip = _Unwind_GetIP(context);
DEBUG(print("called unwind callback\n"));
if (ip != 0x0) {
if (s->frames_skip == 0) {
s->frames[s->frames_size] = ip;
s->frames_size++;
} else {
s->frames_skip--;
}
}
if (s->frames_size == BACKTRACE_FRAMES_MAX) {
return _URC_END_OF_STACK;
} else {
DEBUG(print("returned _URC_OK\n"));
return _URC_OK;
}
}
#endif
/* Use libcorkscrew to get a backtrace inside a signal handler.
Will only return a non-zero code on Android >= 4 (with libcorkscrew.so
being shipped) */
#ifdef USE_CORKSCREW
static size_t coffeecatch_backtrace_signal(siginfo_t* si, void* sc,
backtrace_frame_t* frames,
size_t ignore_depth,
size_t max_depth) {
void *const libcorkscrew = dlopen("libcorkscrew.so", RTLD_LAZY | RTLD_LOCAL);
if (libcorkscrew != NULL) {
t_unwind_backtrace_signal_arch unwind_backtrace_signal_arch
= (t_unwind_backtrace_signal_arch)
dlsym(libcorkscrew, "unwind_backtrace_signal_arch");
t_acquire_my_map_info_list acquire_my_map_info_list
= (t_acquire_my_map_info_list)
dlsym(libcorkscrew, "acquire_my_map_info_list");
t_release_my_map_info_list release_my_map_info_list
= (t_release_my_map_info_list)
dlsym(libcorkscrew, "release_my_map_info_list");
if (unwind_backtrace_signal_arch != NULL
&& acquire_my_map_info_list != NULL
&& release_my_map_info_list != NULL) {
map_info_t*const info = acquire_my_map_info_list();
const ssize_t size =
unwind_backtrace_signal_arch(si, sc, info, frames, ignore_depth,
max_depth);
release_my_map_info_list(info);
return size >= 0 ? size : 0;
} else {
DEBUG(print("symbols not found in libcorkscrew.so\n"));
}
dlclose(libcorkscrew);
} else {
DEBUG(print("libcorkscrew.so could not be loaded\n"));
}
return 0;
}
static int coffeecatch_backtrace_symbols(const backtrace_frame_t* backtrace,
size_t frames,
void (*fun)(void *arg,
const backtrace_symbol_t *sym),
void *arg) {
int success = 0;
void *const libcorkscrew = dlopen("libcorkscrew.so", RTLD_LAZY | RTLD_LOCAL);
if (libcorkscrew != NULL) {
t_get_backtrace_symbols get_backtrace_symbols
= (t_get_backtrace_symbols)
dlsym(libcorkscrew, "get_backtrace_symbols");
t_free_backtrace_symbols free_backtrace_symbols
= (t_free_backtrace_symbols)
dlsym(libcorkscrew, "free_backtrace_symbols");
if (get_backtrace_symbols != NULL
&& free_backtrace_symbols != NULL) {
backtrace_symbol_t symbols[BACKTRACE_FRAMES_MAX];
size_t i;
if (frames > BACKTRACE_FRAMES_MAX) {
frames = BACKTRACE_FRAMES_MAX;
}
get_backtrace_symbols(backtrace, frames, symbols);
for(i = 0; i < frames; i++) {
fun(arg, &symbols[i]);
}
free_backtrace_symbols(symbols, frames);
success = 1;
} else {
DEBUG(print("symbols not found in libcorkscrew.so\n"));
}
dlclose(libcorkscrew);
} else {
DEBUG(print("libcorkscrew.so could not be loaded\n"));
}
return success;
}
#endif
/* Use libunwind to get a backtrace inside a signal handler.
Will only return a non-zero code on Android >= 5 (with libunwind.so
being shipped) */
#ifdef USE_LIBUNWIND
static ssize_t coffeecatch_unwind_signal(siginfo_t* si, void* sc,
void** frames,
size_t ignore_depth,
size_t max_depth) {
void *libunwind = dlopen("libunwind.so", RTLD_LAZY | RTLD_LOCAL);
if (libunwind != NULL) {
int (*backtrace)(void **buffer, int size) =
dlsym(libunwind, "unw_backtrace");
if (backtrace != NULL) {
int nb = backtrace(frames, max_depth);
if (nb > 0) {
}
return nb;
} else {
DEBUG(print("symbols not found in libunwind.so\n"));
}
dlclose(libunwind);
} else {
DEBUG(print("libunwind.so could not be loaded\n"));
}
return -1;
}
#endif
/* Call the old handler. */
static void coffeecatch_call_old_signal_handler(const int code, siginfo_t *const si,
void * const sc) {
/* Call the "real" Java handler for JIT and internals. */
if (code >= 0 && code < SIG_NUMBER_MAX) {
if (native_code_g.sa_old[code].sa_sigaction != NULL) {
native_code_g.sa_old[code].sa_sigaction(code, si, sc);
} else if (native_code_g.sa_old[code].sa_handler != NULL) {
native_code_g.sa_old[code].sa_handler(code);
}
}
}
/* Unflag "on stack" */
static void coffeecatch_revert_alternate_stack(void) {
#ifndef NO_USE_SIGALTSTACK
stack_t ss;
if (sigaltstack(NULL, &ss) == 0) {
ss.ss_flags &= ~SS_ONSTACK;
sigaltstack (&ss, NULL);
}
#endif
}
/* Try to jump to userland. */
static void coffeecatch_try_jump_userland(native_code_handler_struct*
const t,
const int code,
siginfo_t *const si,
void * const sc) {
(void) si; /* UNUSED */
(void) sc; /* UNUSED */
/* Valid context ? */
if (t != NULL && t->ctx_is_set) {
DEBUG(print("calling siglongjmp()\n"));
/* Invalidate the context */
t->ctx_is_set = 0;
/* We need to revert the alternate stack before jumping. */
coffeecatch_revert_alternate_stack();
/*
* Note on async-signal-safety of siglongjmp() [POSIX] :
* "Note that longjmp() and siglongjmp() are not in the list of
* async-signal-safe functions. This is because the code executing after
* longjmp() and siglongjmp() can call any unsafe functions with the same
* danger as calling those unsafe functions directly from the signal
* handler. Applications that use longjmp() and siglongjmp() from within
* signal handlers require rigorous protection in order to be portable.
* Many of the other functions that are excluded from the list are
* traditionally implemented using either malloc() or free() functions or
* the standard I/O library, both of which traditionally use data
* structures in a non-async-signal-safe manner. Since any combination of
* different functions using a common data structure can cause
* async-signal-safety problems, this volume of POSIX.1-2008 does not
* define the behavior when any unsafe function is called in a signal
* handler that interrupts an unsafe function."
*/
siglongjmp(t->ctx, code);
}
}
static void coffeecatch_start_alarm(void) {
/* Ensure we do not deadlock. Default of ALRM is to die.
* (signal() and alarm() are signal-safe) */
(void) alarm(30);
}
static void coffeecatch_mark_alarm(native_code_handler_struct *const t) {
t->alarm = 1;
}
/* Copy context infos (signal code, etc.) */
static void coffeecatch_copy_context(native_code_handler_struct *const t,
const int code, siginfo_t *const si,
void *const sc) {
t->code = code;
t->si = *si;
if (sc != NULL) {
ucontext_t *const uc = (ucontext_t*) sc;
t->uc = *uc;
} else {
memset(&t->uc, 0, sizeof(t->uc));
}
#ifdef USE_UNWIND
/* Frame buffer initial position. */
t->frames_size = 0;
/* Skip us and the caller. */
t->frames_skip = 2;
/* Use the corkscrew library to extract the backtrace. */
#ifdef USE_CORKSCREW
t->frames_size = coffeecatch_backtrace_signal(si, sc, t->frames, 0,
BACKTRACE_FRAMES_MAX);
#else
/* Unwind frames (equivalent to backtrace()) */
_Unwind_Backtrace(coffeecatch_unwind_callback, t);
#endif
#ifdef USE_LIBUNWIND
if (t->frames_size == 0) {
size_t i;
t->frames_size = coffeecatch_unwind_signal(si, sc, t->uframes, 0,
BACKTRACE_FRAMES_MAX);
for(i = 0 ; i < t->frames_size ; i++) {
t->frames[i].absolute_pc = (uintptr_t) t->uframes[i];
t->frames[i].stack_top = 0;
t->frames[i].stack_size = 0;
}
}
#endif
if (t->frames_size != 0) {
DEBUG(print("called _Unwind_Backtrace()\n"));
} else {
DEBUG(print("called _Unwind_Backtrace(), but no traces\n"));
}
#endif
}
/* Return the thread-specific native_code_handler_struct structure, or
* @c null if no such structure is available. */
static native_code_handler_struct* coffeecatch_get() {
return (native_code_handler_struct*)
pthread_getspecific(native_code_thread);
}
int coffeecatch_cancel_pending_alarm() {
native_code_handler_struct *const t = coffeecatch_get();
if (t != NULL && t->alarm) {
t->alarm = 0;
/* "If seconds is 0, a pending alarm request, if any, is canceled." */
alarm(0);
return 0;
}
return -1;
}
/* Internal signal pass-through. Allows to peek the "real" crash before
* calling the Java handler. Remember than Java needs many of the signals
* (for the JIT, for test-free NullPointerException handling, etc.)
* We record the siginfo_t context in this function each time it is being
* called, to be able to know what error caused an issue.
*/
static void coffeecatch_signal_pass(const int code, siginfo_t *const si,
void *const sc) {
native_code_handler_struct *t;
DEBUG(print("caught signal\n"));
/* Call the "real" Java handler for JIT and internals. */
coffeecatch_call_old_signal_handler(code, si, sc);
/* Still here ?
* FIXME TODO: This is the Dalvik behavior - but is it the SunJVM one ? */
/* Ensure we do not deadlock. Default of ALRM is to die.
* (signal() and alarm() are signal-safe) */
signal(code, SIG_DFL);
coffeecatch_start_alarm();
/* Available context ? */
t = coffeecatch_get();
if (t != NULL) {
/* An alarm() call was triggered. */
coffeecatch_mark_alarm(t);
/* Take note of the signal. */
coffeecatch_copy_context(t, code, si, sc);
/* Back to the future. */
coffeecatch_try_jump_userland(t, code, si, sc);
}
/* Nope. (abort() is signal-safe) */
DEBUG(print("calling abort()\n"));
signal(SIGABRT, SIG_DFL);
abort();
}
/* Internal crash handler for abort(). Java calls abort() if its signal handler
* could not resolve the signal ; thus calling us through this handler. */
static void coffeecatch_signal_abort(const int code, siginfo_t *const si,
void *const sc) {
native_code_handler_struct *t;
(void) sc; /* UNUSED */
DEBUG(print("caught abort\n"));
/* Ensure we do not deadlock. Default of ALRM is to die.
* (signal() and alarm() are signal-safe) */
signal(code, SIG_DFL);
coffeecatch_start_alarm();
/* Available context ? */
t = coffeecatch_get();
if (t != NULL) {
/* An alarm() call was triggered. */
coffeecatch_mark_alarm(t);
/* Take note (real "abort()") */
coffeecatch_copy_context(t, code, si, sc);
/* Back to the future. */
coffeecatch_try_jump_userland(t, code, si, sc);
}
/* No such restore point, call old signal handler then. */
DEBUG(print("calling old signal handler\n"));
coffeecatch_call_old_signal_handler(code, si, sc);
/* Nope. (abort() is signal-safe) */
DEBUG(print("calling abort()\n"));
abort();
}
/* Internal globals initialization. */
static int coffeecatch_handler_setup_global(void) {
if (native_code_g.initialized++ == 0) {
size_t i;
struct sigaction sa_abort;
struct sigaction sa_pass;
DEBUG(print("installing global signal handlers\n"));
/* Setup handler structure. */
memset(&sa_abort, 0, sizeof(sa_abort));
sigemptyset(&sa_abort.sa_mask);
sa_abort.sa_sigaction = coffeecatch_signal_abort;
sa_abort.sa_flags = SA_SIGINFO | SA_ONSTACK;
memset(&sa_pass, 0, sizeof(sa_pass));
sigemptyset(&sa_pass.sa_mask);
sa_pass.sa_sigaction = coffeecatch_signal_pass;
sa_pass.sa_flags = SA_SIGINFO | SA_ONSTACK;
/* Allocate */
native_code_g.sa_old = calloc(sizeof(struct sigaction), SIG_NUMBER_MAX);
if (native_code_g.sa_old == NULL) {
return -1;
}
/* Setup signal handlers for SIGABRT (Java calls abort()) and others. **/
for (i = 0; native_sig_catch[i] != 0; i++) {
const int sig = native_sig_catch[i];
const struct sigaction * const action =
sig == SIGABRT ? &sa_abort : &sa_pass;
assert(sig < SIG_NUMBER_MAX);
if (sigaction(sig, action, &native_code_g.sa_old[sig]) != 0) {
return -1;
}
}
/* Initialize thread var. */
if (pthread_key_create(&native_code_thread, NULL) != 0) {
return -1;
}
DEBUG(print("installed global signal handlers\n"));
}
/* OK. */
return 0;
}
/**
* Free a native_code_handler_struct structure.
**/
static int coffeecatch_native_code_handler_struct_free(native_code_handler_struct *const t) {
int code = 0;
if (t == NULL) {
return -1;
}
#ifndef NO_USE_SIGALTSTACK
/* Restore previous alternative stack. */
if (t->stack_old.ss_sp != NULL && sigaltstack(&t->stack_old, NULL) != 0) {
#ifndef USE_SILENT_SIGALTSTACK
code = -1;
#endif
}
#endif
/* Free alternative stack */
if (t->stack_buffer != NULL) {
free(t->stack_buffer);
t->stack_buffer = NULL;
t->stack_buffer_size = 0;
}
/* Free structure. */
free(t);
return code;
}
/**
* Create a native_code_handler_struct structure.
**/
static native_code_handler_struct* coffeecatch_native_code_handler_struct_init(void) {
stack_t stack;
native_code_handler_struct *const t =
calloc(sizeof(native_code_handler_struct), 1);
if (t == NULL) {
return NULL;
}
DEBUG(print("installing thread alternative stack\n"));
/* Initialize structure */
t->stack_buffer_size = SIG_STACK_BUFFER_SIZE;
t->stack_buffer = malloc(t->stack_buffer_size);
if (t->stack_buffer == NULL) {
coffeecatch_native_code_handler_struct_free(t);
return NULL;
}
/* Setup alternative stack. */
memset(&stack, 0, sizeof(stack));
stack.ss_sp = t->stack_buffer;
stack.ss_size = t->stack_buffer_size;
stack.ss_flags = 0;
#ifndef NO_USE_SIGALTSTACK
/* Install alternative stack. This is thread-safe */
if (sigaltstack(&stack, &t->stack_old) != 0) {
#ifndef USE_SILENT_SIGALTSTACK
coffeecatch_native_code_handler_struct_free(t);
return NULL;
#endif
}
#endif
return t;
}
/**
* Acquire the crash handler for the current thread.
* The coffeecatch_handler_cleanup() must be called to release allocated
* resources.
**/
static int coffeecatch_handler_setup(int setup_thread) {
int code;
DEBUG(print("setup for a new handler\n"));
/* Initialize globals. */
if (pthread_mutex_lock(&native_code_g.mutex) != 0) {
return -1;
}
code = coffeecatch_handler_setup_global();
if (pthread_mutex_unlock(&native_code_g.mutex) != 0) {
return -1;
}
/* Global initialization failed. */
if (code != 0) {
return -1;
}
/* Initialize locals. */
if (setup_thread && coffeecatch_get() == NULL) {
native_code_handler_struct *const t =
coffeecatch_native_code_handler_struct_init();
if (t == NULL) {
return -1;
}
DEBUG(print("installing thread alternative stack\n"));
/* Set thread-specific value. */
if (pthread_setspecific(native_code_thread, t) != 0) {
coffeecatch_native_code_handler_struct_free(t);
return -1;
}
DEBUG(print("installed thread alternative stack\n"));
}
/* OK. */
return 0;
}
/**
* Release the resources allocated by a previous call to
* coffeecatch_handler_setup().
* This function must be called as many times as
* coffeecatch_handler_setup() was called to fully release allocated
* resources.
**/
static int coffeecatch_handler_cleanup() {
/* Cleanup locals. */
native_code_handler_struct *const t = coffeecatch_get();
if (t != NULL) {
DEBUG(print("removing thread alternative stack\n"));
/* Erase thread-specific value now (detach). */
if (pthread_setspecific(native_code_thread, NULL) != 0) {
assert(! "pthread_setspecific() failed");
}
/* Free handler and reset slternate stack */
if (coffeecatch_native_code_handler_struct_free(t) != 0) {
return -1;
}
DEBUG(print("removed thread alternative stack\n"));
}
/* Cleanup globals. */
if (pthread_mutex_lock(&native_code_g.mutex) != 0) {
assert(! "pthread_mutex_lock() failed");
}
assert(native_code_g.initialized != 0);
if (--native_code_g.initialized == 0) {
size_t i;
DEBUG(print("removing global signal handlers\n"));
/* Restore signal handler. */
for(i = 0; native_sig_catch[i] != 0; i++) {
const int sig = native_sig_catch[i];
assert(sig < SIG_NUMBER_MAX);
if (sigaction(sig, &native_code_g.sa_old[sig], NULL) != 0) {
return -1;
}
}
/* Free old structure. */
free(native_code_g.sa_old);
native_code_g.sa_old = NULL;
/* Delete thread var. */
if (pthread_key_delete(native_code_thread) != 0) {
assert(! "pthread_key_delete() failed");
}
DEBUG(print("removed global signal handlers\n"));
}
if (pthread_mutex_unlock(&native_code_g.mutex) != 0) {
assert(! "pthread_mutex_unlock() failed");
}
return 0;
}
/**
* Get the signal associated with the crash.
*/
int coffeecatch_get_signal() {
const native_code_handler_struct* const t = coffeecatch_get();
if (t != NULL) {
return t->code;
} else {
return -1;
}
}
/* Signal descriptions.
See <http://pubs.opengroup.org/onlinepubs/009696699/basedefs/signal.h.html>
*/
static const char* coffeecatch_desc_sig(int sig, int code) {
switch(sig) {
case SIGILL:
switch(code) {
case ILL_ILLOPC:
return "Illegal opcode";
case ILL_ILLOPN:
return "Illegal operand";
case ILL_ILLADR:
return "Illegal addressing mode";
case ILL_ILLTRP:
return "Illegal trap";
case ILL_PRVOPC:
return "Privileged opcode";
case ILL_PRVREG:
return "Privileged register";
case ILL_COPROC:
return "Coprocessor error";
case ILL_BADSTK:
return "Internal stack error";
default:
return "Illegal operation";
}
break;
case SIGFPE:
switch(code) {
case FPE_INTDIV:
return "Integer divide by zero";
case FPE_INTOVF:
return "Integer overflow";
case FPE_FLTDIV:
return "Floating-point divide by zero";
case FPE_FLTOVF:
return "Floating-point overflow";
case FPE_FLTUND:
return "Floating-point underflow";
case FPE_FLTRES:
return "Floating-point inexact result";
case FPE_FLTINV:
return "Invalid floating-point operation";
case FPE_FLTSUB:
return "Subscript out of range";
default:
return "Floating-point";
}
break;
case SIGSEGV:
switch(code) {
case SEGV_MAPERR:
return "Address not mapped to object";
case SEGV_ACCERR:
return "Invalid permissions for mapped object";
default:
return "Segmentation violation";
}
break;
case SIGBUS:
switch(code) {
case BUS_ADRALN:
return "Invalid address alignment";
case BUS_ADRERR:
return "Nonexistent physical address";
case BUS_OBJERR:
return "Object-specific hardware error";
default:
return "Bus error";
}
break;
case SIGTRAP:
switch(code) {
case TRAP_BRKPT:
return "Process breakpoint";
case TRAP_TRACE:
return "Process trace trap";
default:
return "Trap";
}
break;
case SIGCHLD:
switch(code) {
case CLD_EXITED:
return "Child has exited";
case CLD_KILLED:
return "Child has terminated abnormally and did not create a core file";
case CLD_DUMPED:
return "Child has terminated abnormally and created a core file";
case CLD_TRAPPED:
return "Traced child has trapped";
case CLD_STOPPED:
return "Child has stopped";
case CLD_CONTINUED:
return "Stopped child has continued";