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Diffstat (limited to 'src/grep/lib/sigsegv.in.h')
| -rw-r--r-- | src/grep/lib/sigsegv.in.h | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/src/grep/lib/sigsegv.in.h b/src/grep/lib/sigsegv.in.h new file mode 100644 index 0000000..17ad87e --- /dev/null +++ b/src/grep/lib/sigsegv.in.h @@ -0,0 +1,244 @@ +/* Page fault handling library. + Copyright (C) 1998-2021 Free Software Foundation, Inc. + + 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, see <https://www.gnu.org/licenses/>. */ + +/* Written by Bruno Haible. */ + +#ifndef _SIGSEGV_H +#define _SIGSEGV_H + +/* Get size_t. */ +#include <stddef.h> + +/* Define the fault context structure. */ +#if defined __linux__ || defined __ANDROID__ \ + || (defined __FreeBSD__ && (defined __arm__ || defined __armhf__ || defined __arm64__)) \ + || defined __NetBSD__ \ + || defined _AIX || defined __sun \ + || defined __CYGWIN__ +/* Linux, FreeBSD, NetBSD, AIX, Solaris, Cygwin */ +# include <ucontext.h> +#elif (defined __APPLE__ && defined __MACH__) +/* macOS */ +# include <sys/ucontext.h> +#elif defined __HAIKU__ +/* Haiku */ +# include <signal.h> +#endif + +/* Correct the value of SIGSTKSZ on some systems. + glibc >= 2.34: When _GNU_SOURCE is defined, SIGSTKSZ is no longer a + compile-time constant. But most programs need a simple constant. + AIX 64-bit: original value 4096 is too small. + HP-UX: original value 8192 is too small. + Solaris 11/x86_64: original value 8192 is too small. */ +#include <signal.h> +#if __GLIBC__ >= 2 +# undef SIGSTKSZ +# if defined __ia64__ +# define SIGSTKSZ 262144 +# else +# define SIGSTKSZ 65536 +# endif +#endif +#if defined _AIX && defined _ARCH_PPC64 +# undef SIGSTKSZ +# define SIGSTKSZ 8192 +#endif +#if defined __hpux || (defined __sun && (defined __x86_64__ || defined __amd64__)) +# undef SIGSTKSZ +# define SIGSTKSZ 16384 +#endif + +/* HAVE_SIGSEGV_RECOVERY + is defined if the system supports catching SIGSEGV. */ +#if defined __linux__ || defined __ANDROID__ || defined __GNU__ \ + || defined __FreeBSD_kernel__ || (defined __FreeBSD__ && !(defined __sparc__ || defined __sparc64__)) || defined __DragonFly__ \ + || defined __NetBSD__ \ + || defined __OpenBSD__ \ + || (defined __APPLE__ && defined __MACH__) \ + || defined _AIX || defined __sgi || defined __sun \ + || defined __CYGWIN__ || defined __HAIKU__ +/* Linux, Hurd, GNU/kFreeBSD, FreeBSD, NetBSD, OpenBSD, macOS, AIX, IRIX, Solaris, Cygwin, Haiku */ +# define HAVE_SIGSEGV_RECOVERY 1 +#endif + +/* HAVE_STACK_OVERFLOW_RECOVERY + is defined if stack overflow can be caught. */ +#if defined __linux__ || defined __ANDROID__ || defined __GNU__ \ + || defined __FreeBSD_kernel__ || (defined __FreeBSD__ && !(defined __sparc__ || defined __sparc64__)) || defined __DragonFly__ \ + || (defined __NetBSD__ && !(defined __sparc__ || defined __sparc64__)) \ + || defined __OpenBSD__ \ + || (defined __APPLE__ && defined __MACH__) \ + || defined _AIX || defined __sgi || defined __sun \ + || defined __CYGWIN__ || defined __HAIKU__ +/* Linux, Hurd, GNU/kFreeBSD, FreeBSD, NetBSD, OpenBSD, macOS, AIX, IRIX, Solaris, Cygwin, Haiku */ +# define HAVE_STACK_OVERFLOW_RECOVERY 1 +#endif + + +#ifdef __cplusplus +extern "C" { +#endif + +#define LIBSIGSEGV_VERSION 0x020D /* version number: (major<<8) + minor */ +extern int libsigsegv_version; /* Likewise */ + +/* -------------------------------------------------------------------------- */ + +#if 1 /* really only HAVE_SIGSEGV_RECOVERY */ + +/* + * The mask of bits that are set to zero in a fault address that gets passed + * to a global SIGSEGV handler. + * On some platforms, the precise fault address is not known, only the memory + * page into which the fault address falls. This is apparently allowed by POSIX: + * <http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/signal.h.html> + * says: "For some implementations, the value of si_addr may be inaccurate." + * In this case, the returned fault address is rounded down to a multiple of + * getpagesize() = sysconf(_SC_PAGESIZE). + * On such platforms, we define SIGSEGV_FAULT_ADDRESS_ALIGNMENT to be an upper + * bound for getpagesize() (and, like getpagesize(), also a power of 2). + * On the platforms where the returned fault address is the precise one, we + * define SIGSEGV_FAULT_ADDRESS_ALIGNMENT to 1. + */ +# if defined __NetBSD__ && (defined __sparc__ || defined __sparc64__) + /* getpagesize () is 0x1000 or 0x2000, depending on hardware. */ +# define SIGSEGV_FAULT_ADDRESS_ALIGNMENT 0x2000UL +# elif defined __linux__ && (defined __s390__ || defined __s390x__) + /* getpagesize () is 0x1000. */ +# define SIGSEGV_FAULT_ADDRESS_ALIGNMENT 0x1000UL +# else +# define SIGSEGV_FAULT_ADDRESS_ALIGNMENT 1UL +# endif + +/* + * The type of a global SIGSEGV handler. + * The fault address, with the bits (SIGSEGV_FAULT_ADDRESS_ALIGNMENT - 1) + * cleared, is passed as argument. + * The access type (read access or write access) is not passed; your handler + * has to know itself how to distinguish these two cases. + * The second argument is 0, meaning it could also be a stack overflow, or 1, + * meaning the handler should seriously try to fix the fault. + * The return value should be nonzero if the handler has done its job + * and no other handler should be called, or 0 if the handler declines + * responsibility for the given address. + * + * The handler is run at a moment when nothing about the global state of the + * program is known. Therefore it cannot use facilities that manipulate global + * variables or locks. In particular, it cannot use malloc(); use mmap() + * instead. It cannot use fopen(); use open() instead. Etc. All global + * variables that are accessed by the handler should be marked 'volatile'. + */ +typedef int (*sigsegv_handler_t) (void* fault_address, int serious); + +/* + * Installs a global SIGSEGV handler. + * This should be called once only, and it ignores any previously installed + * SIGSEGV handler. + * Returns 0 on success, or -1 if the system doesn't support catching SIGSEGV. + */ +extern int sigsegv_install_handler (sigsegv_handler_t handler); + +/* + * Deinstalls the global SIGSEGV handler. + * This goes back to the state where no SIGSEGV handler is installed. + */ +extern void sigsegv_deinstall_handler (void); + +/* + * Prepares leaving a SIGSEGV handler (through longjmp or similar means). + * Control is transferred by calling CONTINUATION with CONT_ARG1, CONT_ARG2, + * CONT_ARG3 as arguments. + * CONTINUATION must not return. + * The sigsegv_leave_handler function may return if called from a SIGSEGV + * handler; its return value should be used as the handler's return value. + * The sigsegv_leave_handler function does not return if called from a + * stack overflow handler. + */ +extern int sigsegv_leave_handler (void (*continuation) (void*, void*, void*), void* cont_arg1, void* cont_arg2, void* cont_arg3); + +#endif /* HAVE_SIGSEGV_RECOVERY */ + +#if 1 /* really only HAVE_STACK_OVERFLOW_RECOVERY */ + +/* + * The type of a context passed to a stack overflow handler. + * This type is system dependent; on some platforms it is an 'ucontext_t *', + * on some platforms it is a 'struct sigcontext *', on others merely an + * opaque 'void *'. + */ +# if defined __linux__ || defined __ANDROID__ \ + || (defined __FreeBSD__ && (defined __arm__ || defined __armhf__ || defined __arm64__)) \ + || defined __NetBSD__ \ + || (defined __APPLE__ && defined __MACH__) \ + || defined _AIX || defined __sun \ + || defined __CYGWIN__ || defined __HAIKU__ +typedef ucontext_t *stackoverflow_context_t; +# elif defined __GNU__ \ + || defined __FreeBSD_kernel__ || (defined __FreeBSD__ && !(defined __sparc__ || defined __sparc64__)) || defined __DragonFly__ \ + || defined __OpenBSD__ || defined __sgi +typedef struct sigcontext *stackoverflow_context_t; +# else +typedef void *stackoverflow_context_t; +# endif + +/* + * The type of a stack overflow handler. + * Such a handler should perform a longjmp call in order to reduce the amount + * of stack needed. It must not return. + * The emergency argument is 0 when the stack could be repared, or 1 if the + * application should better save its state and exit now. + * + * The handler is run at a moment when nothing about the global state of the + * program is known. Therefore it cannot use facilities that manipulate global + * variables or locks. In particular, it cannot use malloc(); use mmap() + * instead. It cannot use fopen(); use open() instead. Etc. All global + * variables that are accessed by the handler should be marked 'volatile'. + */ +typedef void (*stackoverflow_handler_t) (int emergency, stackoverflow_context_t scp); + +/* + * Installs a stack overflow handler. + * The extra_stack argument is a pointer to a pre-allocated area used as a + * stack for executing the handler. It typically comes from a static variable + * or from heap-allocated memoty; placing it on the main stack may fail on + * some operating systems. + * Its size, passed in extra_stack_size, should be sufficiently large. The + * following code determines an appropriate size: + * #include <signal.h> + * #ifndef SIGSTKSZ / * glibc defines SIGSTKSZ for this purpose * / + * # define SIGSTKSZ 16384 / * on most platforms, 16 KB are sufficient * / + * #endif + * Returns 0 on success, or -1 if the system doesn't support catching stack + * overflow. + */ +extern int stackoverflow_install_handler (stackoverflow_handler_t handler, + void* extra_stack, size_t extra_stack_size); + +/* + * Deinstalls the stack overflow handler. + */ +extern void stackoverflow_deinstall_handler (void); + +#endif /* HAVE_STACK_OVERFLOW_RECOVERY */ + +/* -------------------------------------------------------------------------- */ + +#ifdef __cplusplus +} +#endif + +#endif /* _SIGSEGV_H */ |