/* * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. * Copyright (c) 1997 by Silicon Graphics. All rights reserved. * * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. * * Permission is hereby granted to use or copy this program * for any purpose, provided the above notices are retained on all copies. * Permission to modify the code and to distribute modified code is granted, * provided the above notices are retained, and a notice that the code was * modified is included with the above copyright notice. * * Original author: Bill Janssen * Heavily modified by Hans Boehm and others */ #include "private/gc_priv.h" /* * This is incredibly OS specific code for tracking down data sections in * dynamic libraries. There appears to be no way of doing this quickly * without groveling through undocumented data structures. We would argue * that this is a bug in the design of the dlopen interface. THIS CODE * MAY BREAK IN FUTURE OS RELEASES. If this matters to you, don't hesitate * to let your vendor know ... * * None of this is safe with dlclose and incremental collection. * But then not much of anything is safe in the presence of dlclose. */ #if !defined(MACOS) && !defined(_WIN32_WCE) && !defined(__CC_ARM) # include #endif /* BTL: avoid circular redefinition of dlopen if GC_SOLARIS_THREADS defined */ #undef GC_MUST_RESTORE_REDEFINED_DLOPEN #if defined(GC_PTHREADS) && !defined(GC_NO_DLOPEN) \ && !defined(GC_NO_THREAD_REDIRECTS) && !defined(GC_USE_LD_WRAP) /* To support threads in Solaris, gc.h interposes on dlopen by */ /* defining "dlopen" to be "GC_dlopen", which is implemented below. */ /* However, both GC_FirstDLOpenedLinkMap() and GC_dlopen() use the */ /* real system dlopen() in their implementation. We first remove */ /* gc.h's dlopen definition and restore it later, after GC_dlopen(). */ # undef dlopen # define GC_MUST_RESTORE_REDEFINED_DLOPEN #endif /* !GC_NO_DLOPEN */ /* A user-supplied routine (custom filter) that might be called to */ /* determine whether a DSO really needs to be scanned by the GC. */ /* 0 means no filter installed. May be unused on some platforms. */ /* FIXME: Add filter support for more platforms. */ STATIC GC_has_static_roots_func GC_has_static_roots = 0; #if (defined(DYNAMIC_LOADING) || defined(MSWIN32) || defined(MSWINCE) \ || defined(CYGWIN32)) && !defined(PCR) #if !defined(SOLARISDL) && !defined(IRIX5) && \ !defined(MSWIN32) && !defined(MSWINCE) && !defined(CYGWIN32) && \ !(defined(ALPHA) && defined(OSF1)) && \ !defined(HPUX) && !(defined(LINUX) && defined(__ELF__)) && \ !defined(AIX) && !defined(SCO_ELF) && !defined(DGUX) && \ !(defined(FREEBSD) && defined(__ELF__)) && \ !(defined(OPENBSD) && (defined(__ELF__) || defined(M68K))) && \ !(defined(NETBSD) && defined(__ELF__)) && !defined(HURD) && \ !defined(DARWIN) && !defined(CYGWIN32) --> We only know how to find data segments of dynamic libraries for the --> above. Additional SVR4 variants might not be too --> hard to add. #endif #include #ifdef SOLARISDL # include # include # include #endif #if defined(NETBSD) # include # include # include # define ELFSIZE ARCH_ELFSIZE #endif #if defined(SCO_ELF) || defined(DGUX) || defined(HURD) \ || (defined(__ELF__) && (defined(LINUX) || defined(FREEBSD) \ || defined(NETBSD) || defined(OPENBSD))) # include # if !defined(OPENBSD) && !defined(PLATFORM_ANDROID) /* FIXME: Why we exclude it for OpenBSD? */ /* Exclude Android because linker.h below includes its own version. */ # include # endif # ifdef PLATFORM_ANDROID /* The header file is in "bionic/linker" folder of Android sources. */ /* If you don't need the "dynamic loading" feature, you may build */ /* the collector with -D IGNORE_DYNAMIC_LOADING. */ # include # else # include # endif #endif /* Newer versions of GNU/Linux define this macro. We * define it similarly for any ELF systems that don't. */ # ifndef ElfW # if defined(FREEBSD) # if __ELF_WORD_SIZE == 32 # define ElfW(type) Elf32_##type # else # define ElfW(type) Elf64_##type # endif # elif defined(NETBSD) || defined(OPENBSD) # if ELFSIZE == 32 # define ElfW(type) Elf32_##type # else # define ElfW(type) Elf64_##type # endif # else # if !defined(ELF_CLASS) || ELF_CLASS == ELFCLASS32 # define ElfW(type) Elf32_##type # else # define ElfW(type) Elf64_##type # endif # endif # endif #if defined(SOLARISDL) && !defined(USE_PROC_FOR_LIBRARIES) #ifdef LINT Elf32_Dyn _DYNAMIC; #endif STATIC struct link_map * GC_FirstDLOpenedLinkMap(void) { extern ElfW(Dyn) _DYNAMIC; ElfW(Dyn) *dp; static struct link_map * cachedResult = 0; static ElfW(Dyn) *dynStructureAddr = 0; /* BTL: added to avoid Solaris 5.3 ld.so _DYNAMIC bug */ # ifdef SUNOS53_SHARED_LIB /* BTL: Avoid the Solaris 5.3 bug that _DYNAMIC isn't being set */ /* up properly in dynamically linked .so's. This means we have */ /* to use its value in the set of original object files loaded */ /* at program startup. */ if( dynStructureAddr == 0 ) { void* startupSyms = dlopen(0, RTLD_LAZY); dynStructureAddr = (ElfW(Dyn)*)dlsym(startupSyms, "_DYNAMIC"); } # else dynStructureAddr = &_DYNAMIC; # endif if( dynStructureAddr == 0) { return(0); } if( cachedResult == 0 ) { int tag; for( dp = ((ElfW(Dyn) *)(&_DYNAMIC)); (tag = dp->d_tag) != 0; dp++ ) { if( tag == DT_DEBUG ) { struct link_map *lm = ((struct r_debug *)(dp->d_un.d_ptr))->r_map; if( lm != 0 ) cachedResult = lm->l_next; /* might be NULL */ break; } } } return cachedResult; } #endif /* SOLARISDL ... */ /* BTL: added to fix circular dlopen definition if GC_SOLARIS_THREADS defined */ # ifdef GC_MUST_RESTORE_REDEFINED_DLOPEN # define dlopen GC_dlopen # endif # if defined(SOLARISDL) /* Add dynamic library data sections to the root set. */ # if !defined(PCR) && !defined(GC_SOLARIS_THREADS) && defined(THREADS) --> fix mutual exclusion with dlopen # endif # ifndef USE_PROC_FOR_LIBRARIES GC_INNER void GC_register_dynamic_libraries(void) { struct link_map *lm; for (lm = GC_FirstDLOpenedLinkMap(); lm != 0; lm = lm->l_next) { ElfW(Ehdr) * e; ElfW(Phdr) * p; unsigned long offset; char * start; int i; e = (ElfW(Ehdr) *) lm->l_addr; # ifdef PLATFORM_ANDROID if (e == NULL) continue; # endif p = ((ElfW(Phdr) *)(((char *)(e)) + e->e_phoff)); offset = ((unsigned long)(lm->l_addr)); for( i = 0; i < (int)e->e_phnum; i++, p++ ) { switch( p->p_type ) { case PT_LOAD: { if( !(p->p_flags & PF_W) ) break; start = ((char *)(p->p_vaddr)) + offset; GC_add_roots_inner( start, start + p->p_memsz, TRUE ); } break; default: break; } } } } # endif /* !USE_PROC ... */ # endif /* SOLARISDL */ #if defined(SCO_ELF) || defined(DGUX) || defined(HURD) \ || (defined(__ELF__) && (defined(LINUX) || defined(FREEBSD) \ || defined(NETBSD) || defined(OPENBSD))) #ifdef USE_PROC_FOR_LIBRARIES #include #include #include #include #define MAPS_BUF_SIZE (32*1024) /* Sort an array of HeapSects by start address. */ /* Unfortunately at least some versions of */ /* Linux qsort end up calling malloc by way of sysconf, and hence can't */ /* be used in the collector. Hence we roll our own. Should be */ /* reasonably fast if the array is already mostly sorted, as we expect */ /* it to be. */ static void sort_heap_sects(struct HeapSect *base, size_t number_of_elements) { signed_word n = (signed_word)number_of_elements; signed_word nsorted = 1; signed_word i; while (nsorted < n) { while (nsorted < n && base[nsorted-1].hs_start < base[nsorted].hs_start) ++nsorted; if (nsorted == n) break; GC_ASSERT(base[nsorted-1].hs_start > base[nsorted].hs_start); i = nsorted - 1; while (i >= 0 && base[i].hs_start > base[i+1].hs_start) { struct HeapSect tmp = base[i]; base[i] = base[i+1]; base[i+1] = tmp; --i; } GC_ASSERT(base[nsorted-1].hs_start < base[nsorted].hs_start); ++nsorted; } } STATIC word GC_register_map_entries(char *maps) { char *prot; char *buf_ptr = maps; ptr_t start, end; unsigned int maj_dev; ptr_t least_ha, greatest_ha; unsigned i; ptr_t datastart; # ifdef DATASTART_IS_FUNC static ptr_t datastart_cached = (ptr_t)(word)-1; /* Evaluate DATASTART only once. */ if (datastart_cached == (ptr_t)(word)-1) { datastart_cached = (ptr_t)(DATASTART); } datastart = datastart_cached; # else datastart = (ptr_t)(DATASTART); # endif GC_ASSERT(I_HOLD_LOCK()); sort_heap_sects(GC_our_memory, GC_n_memory); least_ha = GC_our_memory[0].hs_start; greatest_ha = GC_our_memory[GC_n_memory-1].hs_start + GC_our_memory[GC_n_memory-1].hs_bytes; for (;;) { buf_ptr = GC_parse_map_entry(buf_ptr, &start, &end, &prot, &maj_dev, 0); if (buf_ptr == NULL) return 1; if (prot[1] == 'w') { /* This is a writable mapping. Add it to */ /* the root set unless it is already otherwise */ /* accounted for. */ if (start <= GC_stackbottom && end >= GC_stackbottom) { /* Stack mapping; discard */ continue; } # ifdef THREADS /* This may fail, since a thread may already be */ /* unregistered, but its thread stack may still be there. */ /* That can fail because the stack may disappear while */ /* we're marking. Thus the marker is, and has to be */ /* prepared to recover from segmentation faults. */ if (GC_segment_is_thread_stack(start, end)) continue; /* FIXME: NPTL squirrels */ /* away pointers in pieces of the stack segment that we */ /* don't scan. We work around this */ /* by treating anything allocated by libpthread as */ /* uncollectable, as we do in some other cases. */ /* A specifically identified problem is that */ /* thread stacks contain pointers to dynamic thread */ /* vectors, which may be reused due to thread caching. */ /* They may not be marked if the thread is still live. */ /* This specific instance should be addressed by */ /* INCLUDE_LINUX_THREAD_DESCR, but that doesn't quite */ /* seem to suffice. */ /* We currently trace entire thread stacks, if they are */ /* are currently cached but unused. This is */ /* very suboptimal for performance reasons. */ # endif /* We no longer exclude the main data segment. */ if (end <= least_ha || start >= greatest_ha) { /* The easy case; just trace entire segment */ GC_add_roots_inner((char *)start, (char *)end, TRUE); continue; } /* Add sections that don't belong to us. */ i = 0; while (GC_our_memory[i].hs_start + GC_our_memory[i].hs_bytes < start) ++i; GC_ASSERT(i < GC_n_memory); if (GC_our_memory[i].hs_start <= start) { start = GC_our_memory[i].hs_start + GC_our_memory[i].hs_bytes; ++i; } while (i < GC_n_memory && GC_our_memory[i].hs_start < end && start < end) { if ((char *)start < GC_our_memory[i].hs_start) GC_add_roots_inner((char *)start, GC_our_memory[i].hs_start, TRUE); start = GC_our_memory[i].hs_start + GC_our_memory[i].hs_bytes; ++i; } if (start < end) GC_add_roots_inner((char *)start, (char *)end, TRUE); } } return 1; } GC_INNER void GC_register_dynamic_libraries(void) { if (!GC_register_map_entries(GC_get_maps())) ABORT("Failed to read /proc for library registration"); } /* We now take care of the main data segment ourselves: */ GC_INNER GC_bool GC_register_main_static_data(void) { return FALSE; } # define HAVE_REGISTER_MAIN_STATIC_DATA #else /* !USE_PROC_FOR_LIBRARIES */ /* The following is the preferred way to walk dynamic libraries */ /* For glibc 2.2.4+. Unfortunately, it doesn't work for older */ /* versions. Thanks to Jakub Jelinek for most of the code. */ #if (defined(LINUX) || defined (__GLIBC__)) /* Are others OK here, too? */ \ && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \ || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG))) /* We have the header files for a glibc that includes dl_iterate_phdr. */ /* It may still not be available in the library on the target system. */ /* Thus we also treat it as a weak symbol. */ # define HAVE_DL_ITERATE_PHDR # pragma weak dl_iterate_phdr #endif #if (defined(FREEBSD) && __FreeBSD__ >= 7) /* On the FreeBSD system, any target system at major version 7 shall */ /* have dl_iterate_phdr; therefore, we need not make it weak as above. */ # define HAVE_DL_ITERATE_PHDR # define DL_ITERATE_PHDR_STRONG #endif #if defined(HAVE_DL_ITERATE_PHDR) # ifdef PT_GNU_RELRO /* Instead of registering PT_LOAD sections directly, we keep them */ /* in a temporary list, and filter them by excluding PT_GNU_RELRO */ /* segments. Processing PT_GNU_RELRO sections with */ /* GC_exclude_static_roots instead would be superficially cleaner. But */ /* it runs into trouble if a client registers an overlapping segment, */ /* which unfortunately seems quite possible. */ # define MAX_LOAD_SEGS MAX_ROOT_SETS static struct load_segment { ptr_t start; ptr_t end; /* Room for a second segment if we remove a RELRO segment */ /* from the middle. */ ptr_t start2; ptr_t end2; } load_segs[MAX_LOAD_SEGS]; static int n_load_segs; # endif /* PT_GNU_RELRO */ STATIC int GC_register_dynlib_callback(struct dl_phdr_info * info, size_t size, void * ptr) { const ElfW(Phdr) * p; ptr_t start, end; int i; /* Make sure struct dl_phdr_info is at least as big as we need. */ if (size < offsetof (struct dl_phdr_info, dlpi_phnum) + sizeof (info->dlpi_phnum)) return -1; p = info->dlpi_phdr; for( i = 0; i < (int)info->dlpi_phnum; i++, p++ ) { switch( p->p_type ) { # ifdef PT_GNU_RELRO case PT_GNU_RELRO: /* This entry is known to be constant and will eventually be remapped read-only. However, the address range covered by this entry is typically a subset of a previously encountered `LOAD' segment, so we need to exclude it. */ { int j; start = ((ptr_t)(p->p_vaddr)) + info->dlpi_addr; end = start + p->p_memsz; for (j = n_load_segs; --j >= 0; ) { if (start >= load_segs[j].start && start < load_segs[j].end) { if (load_segs[j].start2 != 0) { WARN("More than one GNU_RELRO segment per load seg\n",0); } else { GC_ASSERT(end <= load_segs[j].end); /* Remove from the existing load segment */ load_segs[j].end2 = load_segs[j].end; load_segs[j].end = start; load_segs[j].start2 = end; } break; } if (j == 0) WARN("Failed to find PT_GNU_RELRO segment" " inside PT_LOAD region", 0); } } break; # endif case PT_LOAD: { GC_has_static_roots_func callback = GC_has_static_roots; if( !(p->p_flags & PF_W) ) break; start = ((char *)(p->p_vaddr)) + info->dlpi_addr; end = start + p->p_memsz; if (callback != 0 && !callback(info->dlpi_name, start, p->p_memsz)) break; # ifdef PT_GNU_RELRO if (n_load_segs >= MAX_LOAD_SEGS) ABORT("Too many PT_LOAD segs"); # if CPP_WORDSZ == 64 /* FIXME: GC_push_all eventually does the correct */ /* rounding to the next multiple of ALIGNMENT, so, most */ /* probably, we should remove the corresponding assertion */ /* check in GC_add_roots_inner along with this code line. */ /* start pointer value may require aligning */ start = (ptr_t)((word)start & ~(sizeof(word) - 1)); # endif load_segs[n_load_segs].start = start; load_segs[n_load_segs].end = end; load_segs[n_load_segs].start2 = 0; load_segs[n_load_segs].end2 = 0; ++n_load_segs; # else GC_add_roots_inner(start, end, TRUE); # endif /* PT_GNU_RELRO */ } break; default: break; } } *(int *)ptr = 1; /* Signal that we were called */ return 0; } /* Do we need to separately register the main static data segment? */ GC_INNER GC_bool GC_register_main_static_data(void) { # ifdef DL_ITERATE_PHDR_STRONG /* If dl_iterate_phdr is not a weak symbol then don't test against */ /* zero (otherwise a compiler might issue a warning). */ return FALSE; # else return (dl_iterate_phdr == 0); /* implicit conversion to function ptr */ # endif } /* Return TRUE if we succeed, FALSE if dl_iterate_phdr wasn't there. */ STATIC GC_bool GC_register_dynamic_libraries_dl_iterate_phdr(void) { int did_something; if (GC_register_main_static_data()) return FALSE; # ifdef PT_GNU_RELRO { static GC_bool excluded_segs = FALSE; n_load_segs = 0; if (!excluded_segs) { GC_exclude_static_roots_inner((ptr_t)load_segs, (ptr_t)load_segs + sizeof(load_segs)); excluded_segs = TRUE; } } # endif did_something = 0; dl_iterate_phdr(GC_register_dynlib_callback, &did_something); if (did_something) { # ifdef PT_GNU_RELRO int i; for (i = 0; i < n_load_segs; ++i) { if (load_segs[i].end > load_segs[i].start) { GC_add_roots_inner(load_segs[i].start, load_segs[i].end, TRUE); } if (load_segs[i].end2 > load_segs[i].start2) { GC_add_roots_inner(load_segs[i].start2, load_segs[i].end2, TRUE); } } # endif } else { char *datastart; char *dataend; # ifdef DATASTART_IS_FUNC static ptr_t datastart_cached = (ptr_t)(word)-1; /* Evaluate DATASTART only once. */ if (datastart_cached == (ptr_t)(word)-1) { datastart_cached = (ptr_t)(DATASTART); } datastart = (char *)datastart_cached; # else datastart = DATASTART; # endif # ifdef DATAEND_IS_FUNC { static ptr_t dataend_cached = 0; /* Evaluate DATAEND only once. */ if (dataend_cached == 0) { dataend_cached = (ptr_t)(DATAEND); } dataend = (char *)dataend_cached; } # else dataend = DATAEND; # endif /* dl_iterate_phdr may forget the static data segment in */ /* statically linked executables. */ GC_add_roots_inner(datastart, dataend, TRUE); # if defined(DATASTART2) GC_add_roots_inner(DATASTART2, (char *)(DATAEND2), TRUE); # endif } return TRUE; } # define HAVE_REGISTER_MAIN_STATIC_DATA #else /* !HAVE_DL_ITERATE_PHDR */ /* Dynamic loading code for Linux running ELF. Somewhat tested on * Linux/x86, untested but hopefully should work on Linux/Alpha. * This code was derived from the Solaris/ELF support. Thanks to * whatever kind soul wrote that. - Patrick Bridges */ /* This doesn't necessarily work in all cases, e.g. with preloaded * dynamic libraries. */ # if defined(NETBSD) || defined(OPENBSD) # include /* for compatibility with 1.4.x */ # ifndef DT_DEBUG # define DT_DEBUG 21 # endif # ifndef PT_LOAD # define PT_LOAD 1 # endif # ifndef PF_W # define PF_W 2 # endif # elif !defined(PLATFORM_ANDROID) # include # endif # ifndef PLATFORM_ANDROID # include # endif #endif /* !HAVE_DL_ITERATE_PHDR */ #ifdef __GNUC__ # pragma weak _DYNAMIC #endif extern ElfW(Dyn) _DYNAMIC[]; STATIC struct link_map * GC_FirstDLOpenedLinkMap(void) { ElfW(Dyn) *dp; static struct link_map *cachedResult = 0; if( _DYNAMIC == 0) { return(0); } if( cachedResult == 0 ) { # if defined(NETBSD) && defined(RTLD_DI_LINKMAP) struct link_map *lm = NULL; if (!dlinfo(RTLD_SELF, RTLD_DI_LINKMAP, &lm)) cachedResult = lm; # else int tag; for( dp = _DYNAMIC; (tag = dp->d_tag) != 0; dp++ ) { if( tag == DT_DEBUG ) { struct link_map *lm = ((struct r_debug *)(dp->d_un.d_ptr))->r_map; if( lm != 0 ) cachedResult = lm->l_next; /* might be NULL */ break; } } # endif /* !NETBSD || !RTLD_DI_LINKMAP */ } return cachedResult; } GC_INNER void GC_register_dynamic_libraries(void) { struct link_map *lm; # ifdef HAVE_DL_ITERATE_PHDR if (GC_register_dynamic_libraries_dl_iterate_phdr()) { return; } # endif for (lm = GC_FirstDLOpenedLinkMap(); lm != 0; lm = lm->l_next) { ElfW(Ehdr) * e; ElfW(Phdr) * p; unsigned long offset; char * start; int i; e = (ElfW(Ehdr) *) lm->l_addr; # ifdef PLATFORM_ANDROID if (e == NULL) continue; # endif p = ((ElfW(Phdr) *)(((char *)(e)) + e->e_phoff)); offset = ((unsigned long)(lm->l_addr)); for( i = 0; i < (int)e->e_phnum; i++, p++ ) { switch( p->p_type ) { case PT_LOAD: { if( !(p->p_flags & PF_W) ) break; start = ((char *)(p->p_vaddr)) + offset; GC_add_roots_inner(start, start + p->p_memsz, TRUE); } break; default: break; } } } } #endif /* !USE_PROC_FOR_LIBRARIES */ #endif /* LINUX */ #if defined(IRIX5) || (defined(USE_PROC_FOR_LIBRARIES) && !defined(LINUX)) #include #include #include #include #include #include /* Only for the following test. */ #ifndef _sigargs # define IRIX6 #endif /* We use /proc to track down all parts of the address space that are */ /* mapped by the process, and throw out regions we know we shouldn't */ /* worry about. This may also work under other SVR4 variants. */ GC_INNER void GC_register_dynamic_libraries(void) { static int fd = -1; char buf[30]; static prmap_t * addr_map = 0; static int current_sz = 0; /* Number of records currently in addr_map */ static int needed_sz; /* Required size of addr_map */ int i; long flags; ptr_t start; ptr_t limit; ptr_t heap_start = HEAP_START; ptr_t heap_end = heap_start; # ifdef SOLARISDL # define MA_PHYS 0 # endif /* SOLARISDL */ if (fd < 0) { sprintf(buf, "/proc/%ld", (long)getpid()); /* The above generates a lint complaint, since pid_t varies. */ /* It's unclear how to improve this. */ fd = open(buf, O_RDONLY); if (fd < 0) { ABORT("/proc open failed"); } } if (ioctl(fd, PIOCNMAP, &needed_sz) < 0) { GC_err_printf("fd = %d, errno = %d\n", fd, errno); ABORT("/proc PIOCNMAP ioctl failed"); } if (needed_sz >= current_sz) { current_sz = needed_sz * 2 + 1; /* Expansion, plus room for 0 record */ addr_map = (prmap_t *)GC_scratch_alloc( (word)current_sz * sizeof(prmap_t)); if (addr_map == NULL) ABORT("Insufficient memory for address map"); } if (ioctl(fd, PIOCMAP, addr_map) < 0) { GC_err_printf("fd = %d, errno = %d, needed_sz = %d, addr_map = %p\n", fd, errno, needed_sz, addr_map); ABORT("/proc PIOCMAP ioctl failed"); }; if (GC_n_heap_sects > 0) { heap_end = GC_heap_sects[GC_n_heap_sects-1].hs_start + GC_heap_sects[GC_n_heap_sects-1].hs_bytes; if (heap_end < GC_scratch_last_end_ptr) heap_end = GC_scratch_last_end_ptr; } for (i = 0; i < needed_sz; i++) { flags = addr_map[i].pr_mflags; if ((flags & (MA_BREAK | MA_STACK | MA_PHYS | MA_FETCHOP | MA_NOTCACHED)) != 0) goto irrelevant; if ((flags & (MA_READ | MA_WRITE)) != (MA_READ | MA_WRITE)) goto irrelevant; /* The latter test is empirically useless in very old Irix */ /* versions. Other than the */ /* main data and stack segments, everything appears to be */ /* mapped readable, writable, executable, and shared(!!). */ /* This makes no sense to me. - HB */ start = (ptr_t)(addr_map[i].pr_vaddr); if (GC_roots_present(start)) goto irrelevant; if (start < heap_end && start >= heap_start) goto irrelevant; # ifdef MMAP_STACKS if (GC_is_thread_stack(start)) goto irrelevant; # endif /* MMAP_STACKS */ limit = start + addr_map[i].pr_size; /* The following seemed to be necessary for very old versions */ /* of Irix, but it has been reported to discard relevant */ /* segments under Irix 6.5. */ # ifndef IRIX6 if (addr_map[i].pr_off == 0 && strncmp(start, ELFMAG, 4) == 0) { /* Discard text segments, i.e. 0-offset mappings against */ /* executable files which appear to have ELF headers. */ caddr_t arg; int obj; # define MAP_IRR_SZ 10 static ptr_t map_irr[MAP_IRR_SZ]; /* Known irrelevant map entries */ static int n_irr = 0; struct stat buf; register int j; for (j = 0; j < n_irr; j++) { if (map_irr[j] == start) goto irrelevant; } arg = (caddr_t)start; obj = ioctl(fd, PIOCOPENM, &arg); if (obj >= 0) { fstat(obj, &buf); close(obj); if ((buf.st_mode & 0111) != 0) { if (n_irr < MAP_IRR_SZ) { map_irr[n_irr++] = start; } goto irrelevant; } } } # endif /* !IRIX6 */ GC_add_roots_inner(start, limit, TRUE); irrelevant: ; } /* Don't keep cached descriptor, for now. Some kernels don't like us */ /* to keep a /proc file descriptor around during kill -9. */ if (close(fd) < 0) ABORT("Couldn't close /proc file"); fd = -1; } # endif /* USE_PROC || IRIX5 */ # if defined(MSWIN32) || defined(MSWINCE) || defined(CYGWIN32) # ifndef WIN32_LEAN_AND_MEAN # define WIN32_LEAN_AND_MEAN 1 # endif # define NOSERVICE # include # include /* We traverse the entire address space and register all segments */ /* that could possibly have been written to. */ STATIC void GC_cond_add_roots(char *base, char * limit) { # ifdef GC_WIN32_THREADS char * curr_base = base; char * next_stack_lo; char * next_stack_hi; if (base == limit) return; for(;;) { GC_get_next_stack(curr_base, limit, &next_stack_lo, &next_stack_hi); if (next_stack_lo >= limit) break; if (next_stack_lo > curr_base) GC_add_roots_inner(curr_base, next_stack_lo, TRUE); curr_base = next_stack_hi; } if (curr_base < limit) GC_add_roots_inner(curr_base, limit, TRUE); # else char * stack_top = (char *)((word)GC_approx_sp() & ~(GC_sysinfo.dwAllocationGranularity - 1)); if (base == limit) return; if (limit > stack_top && base < GC_stackbottom) { /* Part of the stack; ignore it. */ return; } GC_add_roots_inner(base, limit, TRUE); # endif } #ifdef DYNAMIC_LOADING /* GC_register_main_static_data is not needed unless DYNAMIC_LOADING. */ GC_INNER GC_bool GC_register_main_static_data(void) { # if defined(MSWINCE) || defined(CYGWIN32) /* Do we need to separately register the main static data segment? */ return FALSE; # else return GC_no_win32_dlls; # endif } # define HAVE_REGISTER_MAIN_STATIC_DATA #endif /* DYNAMIC_LOADING */ # ifdef DEBUG_VIRTUALQUERY void GC_dump_meminfo(MEMORY_BASIC_INFORMATION *buf) { GC_printf("BaseAddress = 0x%lx, AllocationBase = 0x%lx," " RegionSize = 0x%lx(%lu)\n", buf -> BaseAddress, buf -> AllocationBase, buf -> RegionSize, buf -> RegionSize); GC_printf("\tAllocationProtect = 0x%lx, State = 0x%lx, Protect = 0x%lx, " "Type = 0x%lx\n", buf -> AllocationProtect, buf -> State, buf -> Protect, buf -> Type); } # endif /* DEBUG_VIRTUALQUERY */ # if defined(MSWINCE) || defined(CYGWIN32) /* FIXME: Should we really need to scan MEM_PRIVATE sections? */ /* For now, we don't add MEM_PRIVATE sections to the data roots for */ /* WinCE because otherwise SEGV fault sometimes happens to occur in */ /* GC_mark_from() (and, even if we use WRAP_MARK_SOME, WinCE prints */ /* a "Data Abort" message to the debugging console). */ /* To workaround that, use -DGC_REGISTER_MEM_PRIVATE. */ # define GC_wnt TRUE # endif GC_INNER void GC_register_dynamic_libraries(void) { MEMORY_BASIC_INFORMATION buf; size_t result; DWORD protect; LPVOID p; char * base; char * limit, * new_limit; # ifdef MSWIN32 if (GC_no_win32_dlls) return; # endif base = limit = p = GC_sysinfo.lpMinimumApplicationAddress; while (p < GC_sysinfo.lpMaximumApplicationAddress) { result = VirtualQuery(p, &buf, sizeof(buf)); # ifdef MSWINCE if (result == 0) { /* Page is free; advance to the next possible allocation base */ new_limit = (char *) (((DWORD) p + GC_sysinfo.dwAllocationGranularity) & ~(GC_sysinfo.dwAllocationGranularity-1)); } else # endif /* else */ { if (result != sizeof(buf)) { ABORT("Weird VirtualQuery result"); } new_limit = (char *)p + buf.RegionSize; protect = buf.Protect; if (buf.State == MEM_COMMIT && (protect == PAGE_EXECUTE_READWRITE || protect == PAGE_READWRITE) && (buf.Type == MEM_IMAGE # ifdef GC_REGISTER_MEM_PRIVATE || (protect == PAGE_READWRITE && buf.Type == MEM_PRIVATE) # else /* There is some evidence that we cannot always */ /* ignore MEM_PRIVATE sections under Windows ME */ /* and predecessors. Hence we now also check for */ /* that case. */ || (!GC_wnt && buf.Type == MEM_PRIVATE) # endif ) && !GC_is_heap_base(buf.AllocationBase)) { # ifdef DEBUG_VIRTUALQUERY GC_dump_meminfo(&buf); # endif if ((char *)p != limit) { GC_cond_add_roots(base, limit); base = p; } limit = new_limit; } } if (p > (LPVOID)new_limit /* overflow */) break; p = (LPVOID)new_limit; } GC_cond_add_roots(base, limit); } #endif /* MSWIN32 || MSWINCE || CYGWIN32 */ #if defined(ALPHA) && defined(OSF1) #include extern char *sys_errlist[]; extern int sys_nerr; extern int errno; GC_INNER void GC_register_dynamic_libraries(void) { int status; ldr_process_t mypid; /* module */ ldr_module_t moduleid = LDR_NULL_MODULE; ldr_module_info_t moduleinfo; size_t moduleinfosize = sizeof(moduleinfo); size_t modulereturnsize; /* region */ ldr_region_t region; ldr_region_info_t regioninfo; size_t regioninfosize = sizeof(regioninfo); size_t regionreturnsize; /* Obtain id of this process */ mypid = ldr_my_process(); /* For each module */ while (TRUE) { /* Get the next (first) module */ status = ldr_next_module(mypid, &moduleid); /* Any more modules? */ if (moduleid == LDR_NULL_MODULE) break; /* No more modules */ /* Check status AFTER checking moduleid because */ /* of a bug in the non-shared ldr_next_module stub */ if (status != 0) { if (GC_print_stats) { GC_log_printf("dynamic_load: status = %d\n", status); if (errno < sys_nerr) { GC_log_printf("dynamic_load: %s\n", sys_errlist[errno]); } else { GC_log_printf("dynamic_load: err_code = %d\n", errno); } } ABORT("ldr_next_module failed"); } /* Get the module information */ status = ldr_inq_module(mypid, moduleid, &moduleinfo, moduleinfosize, &modulereturnsize); if (status != 0 ) ABORT("ldr_inq_module failed"); /* is module for the main program (i.e. nonshared portion)? */ if (moduleinfo.lmi_flags & LDR_MAIN) continue; /* skip the main module */ # ifdef DL_VERBOSE GC_log_printf("---Module---\n"); GC_log_printf("Module ID\t = %16ld\n", moduleinfo.lmi_modid); GC_log_printf("Count of regions = %16d\n", moduleinfo.lmi_nregion); GC_log_printf("flags for module = %16lx\n", moduleinfo.lmi_flags); GC_log_printf("module pathname\t = \"%s\"\n", moduleinfo.lmi_name); # endif /* For each region in this module */ for (region = 0; region < moduleinfo.lmi_nregion; region++) { /* Get the region information */ status = ldr_inq_region(mypid, moduleid, region, ®ioninfo, regioninfosize, ®ionreturnsize); if (status != 0 ) ABORT("ldr_inq_region failed"); /* only process writable (data) regions */ if (! (regioninfo.lri_prot & LDR_W)) continue; # ifdef DL_VERBOSE GC_log_printf("--- Region ---\n"); GC_log_printf("Region number\t = %16ld\n", regioninfo.lri_region_no); GC_log_printf("Protection flags = %016x\n", regioninfo.lri_prot); GC_log_printf("Virtual address\t = %16p\n", regioninfo.lri_vaddr); GC_log_printf("Mapped address\t = %16p\n", regioninfo.lri_mapaddr); GC_log_printf("Region size\t = %16ld\n", regioninfo.lri_size); GC_log_printf("Region name\t = \"%s\"\n", regioninfo.lri_name); # endif /* register region as a garbage collection root */ GC_add_roots_inner((char *)regioninfo.lri_mapaddr, (char *)regioninfo.lri_mapaddr + regioninfo.lri_size, TRUE); } } } #endif #if defined(HPUX) #include #include extern char *sys_errlist[]; extern int sys_nerr; GC_INNER void GC_register_dynamic_libraries(void) { int status; int index = 1; /* Ordinal position in shared library search list */ struct shl_descriptor *shl_desc; /* Shared library info, see dl.h */ /* For each dynamic library loaded */ while (TRUE) { /* Get info about next shared library */ status = shl_get(index, &shl_desc); /* Check if this is the end of the list or if some error occured */ if (status != 0) { # ifdef GC_HPUX_THREADS /* I've seen errno values of 0. The man page is not clear */ /* as to whether errno should get set on a -1 return. */ break; # else if (errno == EINVAL) { break; /* Moved past end of shared library list --> finished */ } else { if (GC_print_stats) { if (errno < sys_nerr) { GC_log_printf("dynamic_load: %s\n", sys_errlist[errno]); } else { GC_log_printf("dynamic_load: err_code = %d\n", errno); } } ABORT("shl_get failed"); } # endif } # ifdef DL_VERBOSE GC_log_printf("---Shared library---\n"); GC_log_printf("\tfilename\t= \"%s\"\n", shl_desc->filename); GC_log_printf("\tindex\t\t= %d\n", index); GC_log_printf("\thandle\t\t= %08x\n", (unsigned long) shl_desc->handle); GC_log_printf("\ttext seg.start\t= %08x\n", shl_desc->tstart); GC_log_printf("\ttext seg.end\t= %08x\n", shl_desc->tend); GC_log_printf("\tdata seg.start\t= %08x\n", shl_desc->dstart); GC_log_printf("\tdata seg.end\t= %08x\n", shl_desc->dend); GC_log_printf("\tref.count\t= %lu\n", shl_desc->ref_count); # endif /* register shared library's data segment as a garbage collection root */ GC_add_roots_inner((char *) shl_desc->dstart, (char *) shl_desc->dend, TRUE); index++; } } #endif /* HPUX */ #ifdef AIX # pragma alloca # include # include GC_INNER void GC_register_dynamic_libraries(void) { int len; char *ldibuf; int ldibuflen; struct ld_info *ldi; ldibuf = alloca(ldibuflen = 8192); while ( (len = loadquery(L_GETINFO,ldibuf,ldibuflen)) < 0) { if (errno != ENOMEM) { ABORT("loadquery failed"); } ldibuf = alloca(ldibuflen *= 2); } ldi = (struct ld_info *)ldibuf; while (ldi) { len = ldi->ldinfo_next; GC_add_roots_inner( ldi->ldinfo_dataorg, (ptr_t)(unsigned long)ldi->ldinfo_dataorg + ldi->ldinfo_datasize, TRUE); ldi = len ? (struct ld_info *)((char *)ldi + len) : 0; } } #endif /* AIX */ #ifdef DARWIN /* __private_extern__ hack required for pre-3.4 gcc versions. */ #ifndef __private_extern__ # define __private_extern__ extern # include # undef __private_extern__ #else # include #endif #include /*#define DARWIN_DEBUG*/ /* Writable sections generally available on Darwin. */ STATIC const struct { const char *seg; const char *sect; } GC_dyld_sections[] = { { SEG_DATA, SECT_DATA }, /* Used by FSF GCC, but not by OS X system tools, so far. */ { SEG_DATA, "__static_data" }, { SEG_DATA, SECT_BSS }, { SEG_DATA, SECT_COMMON }, /* FSF GCC - zero-sized object sections for targets */ /*supporting section anchors. */ { SEG_DATA, "__zobj_data" }, { SEG_DATA, "__zobj_bss" } }; /* Additional writable sections: */ /* GCC on Darwin constructs aligned sections "on demand", where */ /* the alignment size is embedded in the section name. */ /* Furthermore, there are distinctions between sections */ /* containing private vs. public symbols. It also constructs */ /* sections specifically for zero-sized objects, when the */ /* target supports section anchors. */ STATIC const char * GC_dyld_add_sect_fmts[] = { "__bss%u", "__pu_bss%u", "__zo_bss%u", "__zo_pu_bss%u", NULL }; /* Currently, mach-o will allow up to the max of 2^15 alignment */ /* in an object file. */ #ifndef L2_MAX_OFILE_ALIGNMENT # define L2_MAX_OFILE_ALIGNMENT 15 #endif STATIC const char *GC_dyld_name_for_hdr(const struct GC_MACH_HEADER *hdr) { unsigned long i, c; c = _dyld_image_count(); for (i = 0; i < c; i++) if ((const struct GC_MACH_HEADER *)_dyld_get_image_header(i) == hdr) return _dyld_get_image_name(i); return NULL; } /* This should never be called by a thread holding the lock. */ STATIC void GC_dyld_image_add(const struct GC_MACH_HEADER *hdr, intptr_t slide) { unsigned long start, end; unsigned i, j; const struct GC_MACH_SECTION *sec; const char *name; GC_has_static_roots_func callback = GC_has_static_roots; char secnam[16]; const char *fmt; DCL_LOCK_STATE; if (GC_no_dls) return; # ifdef DARWIN_DEBUG name = GC_dyld_name_for_hdr(hdr); # else name = callback != 0 ? GC_dyld_name_for_hdr(hdr) : NULL; # endif for (i = 0; i < sizeof(GC_dyld_sections)/sizeof(GC_dyld_sections[0]); i++) { sec = GC_GETSECTBYNAME(hdr, GC_dyld_sections[i].seg, GC_dyld_sections[i].sect); if (sec == NULL || sec->size < sizeof(word)) continue; start = slide + sec->addr; end = start + sec->size; LOCK(); /* The user callback is called holding the lock. */ if (callback == 0 || callback(name, (void*)start, (size_t)sec->size)) { # ifdef DARWIN_DEBUG GC_log_printf( "Adding section __DATA,%s at %p-%p (%lu bytes) from image %s\n", GC_dyld_sections[i].sect, (void*)start, (void*)end, (unsigned long)sec->size, name); # endif GC_add_roots_inner((ptr_t)start, (ptr_t)end, FALSE); } UNLOCK(); } /* Sections constructed on demand. */ for (j = 0; (fmt = GC_dyld_add_sect_fmts[j]) != NULL; j++) { /* Add our manufactured aligned BSS sections. */ for (i = 0; i <= L2_MAX_OFILE_ALIGNMENT; i++) { snprintf(secnam, sizeof(secnam), fmt, (unsigned)i); sec = GC_GETSECTBYNAME(hdr, SEG_DATA, secnam); if (sec == NULL || sec->size == 0) continue; start = slide + sec->addr; end = start + sec->size; # ifdef DARWIN_DEBUG GC_log_printf("Adding on-demand section __DATA,%s at" " %p-%p (%lu bytes) from image %s\n", secnam, (void*)start, (void*)end, (unsigned long)sec->size, name); # endif GC_add_roots((char*)start, (char*)end); } } # ifdef DARWIN_DEBUG GC_print_static_roots(); # endif } /* This should never be called by a thread holding the lock. */ STATIC void GC_dyld_image_remove(const struct GC_MACH_HEADER *hdr, intptr_t slide) { unsigned long start, end; unsigned i, j; const struct GC_MACH_SECTION *sec; char secnam[16]; const char *fmt; for (i = 0; i < sizeof(GC_dyld_sections)/sizeof(GC_dyld_sections[0]); i++) { sec = GC_GETSECTBYNAME(hdr, GC_dyld_sections[i].seg, GC_dyld_sections[i].sect); if (sec == NULL || sec->size == 0) continue; start = slide + sec->addr; end = start + sec->size; # ifdef DARWIN_DEBUG GC_log_printf( "Removing section __DATA,%s at %p-%p (%lu bytes) from image %s\n", GC_dyld_sections[i].sect, (void*)start, (void*)end, (unsigned long)sec->size, GC_dyld_name_for_hdr(hdr)); # endif GC_remove_roots((char*)start, (char*)end); } /* Remove our on-demand sections. */ for (j = 0; (fmt = GC_dyld_add_sect_fmts[j]) != NULL; j++) { for (i = 0; i <= L2_MAX_OFILE_ALIGNMENT; i++) { snprintf(secnam, sizeof(secnam), fmt, (unsigned)i); sec = GC_GETSECTBYNAME(hdr, SEG_DATA, secnam); if (sec == NULL || sec->size == 0) continue; start = slide + sec->addr; end = start + sec->size; # ifdef DARWIN_DEBUG GC_log_printf("Removing on-demand section __DATA,%s at" " %p-%p (%lu bytes) from image %s\n", secnam, (void*)start, (void*)end, (unsigned long)sec->size, GC_dyld_name_for_hdr(hdr)); # endif GC_remove_roots((char*)start, (char*)end); } } # ifdef DARWIN_DEBUG GC_print_static_roots(); # endif } GC_INNER void GC_register_dynamic_libraries(void) { /* Currently does nothing. The callbacks are setup by GC_init_dyld() The dyld library takes it from there. */ } /* The _dyld_* functions have an internal lock so no _dyld functions can be called while the world is stopped without the risk of a deadlock. Because of this we MUST setup callbacks BEFORE we ever stop the world. This should be called BEFORE any thread in created and WITHOUT the allocation lock held. */ GC_INNER void GC_init_dyld(void) { static GC_bool initialized = FALSE; if (initialized) return; # ifdef DARWIN_DEBUG GC_log_printf("Registering dyld callbacks...\n"); # endif /* Apple's Documentation: When you call _dyld_register_func_for_add_image, the dynamic linker runtime calls the specified callback (func) once for each of the images that is currently loaded into the program. When a new image is added to the program, your callback is called again with the mach_header for the new image, and the virtual memory slide amount of the new image. This WILL properly register already linked libraries and libraries linked in the future. */ _dyld_register_func_for_add_image(GC_dyld_image_add); _dyld_register_func_for_remove_image(GC_dyld_image_remove); /* Ignore 2 compiler warnings here: passing argument 1 of */ /* '_dyld_register_func_for_add/remove_image' from incompatible */ /* pointer type. */ /* Set this early to avoid reentrancy issues. */ initialized = TRUE; # ifdef NO_DYLD_BIND_FULLY_IMAGE /* FIXME: What should we do in this case? */ # else if (GC_no_dls) return; /* skip main data segment registration */ /* When the environment variable is set, the dynamic linker binds */ /* all undefined symbols the application needs at launch time. */ /* This includes function symbols that are normally bound lazily at */ /* the time of their first invocation. */ if (GETENV("DYLD_BIND_AT_LAUNCH") == 0) { /* The environment variable is unset, so we should bind manually. */ # ifdef DARWIN_DEBUG GC_log_printf("Forcing full bind of GC code...\n"); # endif /* FIXME: '_dyld_bind_fully_image_containing_address' is deprecated. */ if (!_dyld_bind_fully_image_containing_address( (unsigned long *)GC_malloc)) ABORT("_dyld_bind_fully_image_containing_address failed"); } # endif } #define HAVE_REGISTER_MAIN_STATIC_DATA GC_INNER GC_bool GC_register_main_static_data(void) { /* Already done through dyld callbacks */ return FALSE; } #endif /* DARWIN */ #elif defined(PCR) # include "il/PCR_IL.h" # include "th/PCR_ThCtl.h" # include "mm/PCR_MM.h" GC_INNER void GC_register_dynamic_libraries(void) { /* Add new static data areas of dynamically loaded modules. */ PCR_IL_LoadedFile * p = PCR_IL_GetLastLoadedFile(); PCR_IL_LoadedSegment * q; /* Skip uncommitted files */ while (p != NIL && !(p -> lf_commitPoint)) { /* The loading of this file has not yet been committed */ /* Hence its description could be inconsistent. */ /* Furthermore, it hasn't yet been run. Hence its data */ /* segments can't possibly reference heap allocated */ /* objects. */ p = p -> lf_prev; } for (; p != NIL; p = p -> lf_prev) { for (q = p -> lf_ls; q != NIL; q = q -> ls_next) { if ((q -> ls_flags & PCR_IL_SegFlags_Traced_MASK) == PCR_IL_SegFlags_Traced_on) { GC_add_roots_inner((char *)(q -> ls_addr), (char *)(q -> ls_addr) + q -> ls_bytes, TRUE); } } } } #endif /* PCR && !DYNAMIC_LOADING && !MSWIN32 */ #if !defined(HAVE_REGISTER_MAIN_STATIC_DATA) && defined(DYNAMIC_LOADING) /* Do we need to separately register the main static data segment? */ GC_INNER GC_bool GC_register_main_static_data(void) { return TRUE; } #endif /* HAVE_REGISTER_MAIN_STATIC_DATA */ /* Register a routine to filter dynamic library registration. */ GC_API void GC_CALL GC_register_has_static_roots_callback( GC_has_static_roots_func callback) { GC_has_static_roots = callback; }