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-rw-r--r--dyn_load.c326
1 files changed, 188 insertions, 138 deletions
diff --git a/dyn_load.c b/dyn_load.c
index b888a52..9a530a2 100644
--- a/dyn_load.c
+++ b/dyn_load.c
@@ -57,7 +57,8 @@
!defined(HPUX) && !(defined(LINUX) && defined(__ELF__)) && \
!defined(RS6000) && !defined(SCO_ELF) && !defined(DGUX) && \
!(defined(FREEBSD) && defined(__ELF__)) && \
- !(defined(NETBSD) && defined(__ELF__)) && !defined(HURD)
+ !(defined(NETBSD) && defined(__ELF__)) && !defined(HURD) && \
+ !defined(DARWIN)
--> We only know how to find data segments of dynamic libraries for the
--> above. Additional SVR4 variants might not be too
--> hard to add.
@@ -282,56 +283,23 @@ extern ssize_t GC_repeat_read(int fd, char *buf, size_t count);
/* Repeatedly read until buffer is filled, or EOF is encountered */
/* Defined in os_dep.c. */
-static char *parse_map_entry(char *buf_ptr, word *start, word *end,
- char *prot_buf, unsigned int *maj_dev);
+char *GC_parse_map_entry(char *buf_ptr, word *start, word *end,
+ char *prot_buf, unsigned int *maj_dev);
+word GC_apply_to_maps(word (*fn)(char *));
+ /* From os_dep.c */
-void GC_register_dynamic_libraries()
+word GC_register_map_entries(char *maps)
{
- int f;
- int result;
char prot_buf[5];
- int maps_size;
- char maps_temp[32768];
- char *maps_buf;
- char *buf_ptr;
+ char *buf_ptr = maps;
int count;
word start, end;
- unsigned int maj_dev, min_dev;
+ unsigned int maj_dev;
word least_ha, greatest_ha;
unsigned i;
word datastart = (word)(DATASTART);
- /* Read /proc/self/maps */
- /* Note that we may not allocate, and thus can't use stdio. */
- f = open("/proc/self/maps", O_RDONLY);
- if (-1 == f) ABORT("Couldn't open /proc/self/maps");
- /* stat() doesn't work for /proc/self/maps, so we have to
- read it to find out how large it is... */
- maps_size = 0;
- do {
- result = GC_repeat_read(f, maps_temp, sizeof(maps_temp));
- if (result <= 0) ABORT("Couldn't read /proc/self/maps");
- maps_size += result;
- } while (result == sizeof(maps_temp));
-
- if (maps_size > sizeof(maps_temp)) {
- /* If larger than our buffer, close and re-read it. */
- close(f);
- f = open("/proc/self/maps", O_RDONLY);
- if (-1 == f) ABORT("Couldn't open /proc/self/maps");
- maps_buf = alloca(maps_size);
- if (NULL == maps_buf) ABORT("/proc/self/maps alloca failed");
- result = GC_repeat_read(f, maps_buf, maps_size);
- if (result <= 0) ABORT("Couldn't read /proc/self/maps");
- } else {
- /* Otherwise use the fixed size buffer */
- maps_buf = maps_temp;
- }
-
- close(f);
- maps_buf[result] = '\0';
- buf_ptr = maps_buf;
- /* Compute heap bounds. Should be done by add_to_heap? */
+ /* Compute heap bounds. FIXME: Should be done by add_to_heap? */
least_ha = (word)(-1);
greatest_ha = 0;
for (i = 0; i < GC_n_heap_sects; ++i) {
@@ -342,11 +310,10 @@ void GC_register_dynamic_libraries()
}
if (greatest_ha < (word)GC_scratch_last_end_ptr)
greatest_ha = (word)GC_scratch_last_end_ptr;
- for (;;) {
-
- buf_ptr = parse_map_entry(buf_ptr, &start, &end, prot_buf, &maj_dev);
- if (buf_ptr == NULL) return;
+ for (;;) {
+ buf_ptr = GC_parse_map_entry(buf_ptr, &start, &end, prot_buf, &maj_dev);
+ if (buf_ptr == NULL) return 1;
if (prot_buf[1] == 'w') {
/* This is a writable mapping. Add it to */
/* the root set unless it is already otherwise */
@@ -355,23 +322,10 @@ void GC_register_dynamic_libraries()
/* Stack mapping; discard */
continue;
}
- if (start <= datastart && end > datastart && maj_dev != 0) {
- /* Main data segment; discard */
- continue;
- }
# ifdef THREADS
if (GC_segment_is_thread_stack(start, end)) continue;
# endif
- /* The rest of this assumes that there is no mapping */
- /* spanning the beginning of the data segment, or extending */
- /* beyond the entire heap at both ends. */
- /* Empirically these assumptions hold. */
-
- if (start < (word)DATAEND && end > (word)DATAEND) {
- /* Rld may use space at the end of the main data */
- /* segment. Thus we add that in. */
- start = (word)DATAEND;
- }
+ /* We no longer exclude the main data segment. */
if (start < least_ha && end > least_ha) {
end = least_ha;
}
@@ -381,76 +335,23 @@ void GC_register_dynamic_libraries()
if (start >= least_ha && end <= greatest_ha) continue;
GC_add_roots_inner((char *)start, (char *)end, TRUE);
}
- }
+ }
+ return 1;
}
-//
-// parse_map_entry parses an entry from /proc/self/maps so we can
-// locate all writable data segments that belong to shared libraries.
-// The format of one of these entries and the fields we care about
-// is as follows:
-// XXXXXXXX-XXXXXXXX r-xp 00000000 30:05 260537 name of mapping...\n
-// ^^^^^^^^ ^^^^^^^^ ^^^^ ^^
-// start end prot maj_dev
-// 0 9 18 32
-//
-// For 64 bit ABIs:
-// 0 17 34 56
-//
-// The parser is called with a pointer to the entry and the return value
-// is either NULL or is advanced to the next entry(the byte after the
-// trailing '\n'.)
-//
-#if CPP_WORDSZ == 32
-# define OFFSET_MAP_START 0
-# define OFFSET_MAP_END 9
-# define OFFSET_MAP_PROT 18
-# define OFFSET_MAP_MAJDEV 32
-# define ADDR_WIDTH 8
-#endif
-
-#if CPP_WORDSZ == 64
-# define OFFSET_MAP_START 0
-# define OFFSET_MAP_END 17
-# define OFFSET_MAP_PROT 34
-# define OFFSET_MAP_MAJDEV 56
-# define ADDR_WIDTH 16
-#endif
-
-static char *parse_map_entry(char *buf_ptr, word *start, word *end,
- char *prot_buf, unsigned int *maj_dev)
+void GC_register_dynamic_libraries()
{
- int i;
- char *tok;
-
- if (buf_ptr == NULL || *buf_ptr == '\0') {
- return NULL;
- }
-
- memcpy(prot_buf, buf_ptr+OFFSET_MAP_PROT, 4); // do the protections first
- prot_buf[4] = '\0';
-
- if (prot_buf[1] == 'w') { // we can skip all of this if it's not writable
-
- tok = buf_ptr;
- buf_ptr[OFFSET_MAP_START+ADDR_WIDTH] = '\0';
- *start = strtoul(tok, NULL, 16);
-
- tok = buf_ptr+OFFSET_MAP_END;
- buf_ptr[OFFSET_MAP_END+ADDR_WIDTH] = '\0';
- *end = strtoul(tok, NULL, 16);
-
- buf_ptr += OFFSET_MAP_MAJDEV;
- tok = buf_ptr;
- while (*buf_ptr != ':') buf_ptr++;
- *buf_ptr++ = '\0';
- *maj_dev = strtoul(tok, NULL, 16);
- }
-
- while (*buf_ptr && *buf_ptr++ != '\n');
+ if (!GC_apply_to_maps(GC_register_map_entries))
+ ABORT("Failed to read /proc for library registration.");
+}
- return buf_ptr;
+/* We now take care of the main data segment ourselves: */
+GC_bool GC_register_main_static_data()
+{
+ return FALSE;
}
+
+# define HAVE_REGISTER_MAIN_STATIC_DATA
#endif /* USE_PROC_FOR_LIBRARIES */
@@ -482,13 +383,6 @@ static int GC_register_dynlib_callback(info, size, ptr)
+ sizeof (info->dlpi_phnum))
return -1;
- /* Skip the first object - it is the main program. */
- if (*(int *)ptr == 0)
- {
- *(int *)ptr = 1;
- return 0;
- }
-
p = info->dlpi_phdr;
for( i = 0; i < (int)(info->dlpi_phnum); ((i++),(p++)) ) {
switch( p->p_type ) {
@@ -504,6 +398,7 @@ static int GC_register_dynlib_callback(info, size, ptr)
}
}
+ * (int *)ptr = 1; /* Signal that we were called */
return 0;
}
@@ -513,16 +408,32 @@ static int GC_register_dynlib_callback(info, size, ptr)
GC_bool GC_register_dynamic_libraries_dl_iterate_phdr()
{
- int tmp = 0;
-
if (dl_iterate_phdr) {
- dl_iterate_phdr(GC_register_dynlib_callback, &tmp);
+ int did_something = 0;
+ dl_iterate_phdr(GC_register_dynlib_callback, &did_something);
+ if (!did_something) {
+ /* dl_iterate_phdr may forget the static data segment in */
+ /* statically linked executables. */
+ GC_add_roots_inner(DATASTART, (char *)(DATAEND), TRUE);
+# if defined(DATASTART2)
+ GC_add_roots_inner(DATASTART2, (char *)(DATAEND2), TRUE);
+# endif
+ }
+
return TRUE;
} else {
return FALSE;
}
}
+/* Do we need to separately register the main static data segment? */
+GC_bool GC_register_main_static_data()
+{
+ return (dl_iterate_phdr == 0);
+}
+
+#define HAVE_REGISTER_MAIN_STATIC_DATA
+
# else /* !LINUX || version(glibc) < 2.2.4 */
/* Dynamic loading code for Linux running ELF. Somewhat tested on
@@ -789,10 +700,23 @@ void GC_register_dynamic_libraries()
}
# endif
-# ifndef MSWINCE
+# ifdef MSWINCE
+ /* Do we need to separately register the main static data segment? */
+ GC_bool GC_register_main_static_data()
+ {
+ return FALSE;
+ }
+# else /* win32 */
extern GC_bool GC_no_win32_dlls;
-# endif
+
+ GC_bool GC_register_main_static_data()
+ {
+ return GC_no_win32_dlls;
+ }
+# endif /* win32 */
+# define HAVE_REGISTER_MAIN_STATIC_DATA
+
void GC_register_dynamic_libraries()
{
MEMORY_BASIC_INFORMATION buf;
@@ -1037,7 +961,7 @@ void GC_register_dynamic_libraries()
len = ldi->ldinfo_next;
GC_add_roots_inner(
ldi->ldinfo_dataorg,
- (unsigned long)ldi->ldinfo_dataorg
+ (ptr_t)(unsigned long)ldi->ldinfo_dataorg
+ ldi->ldinfo_datasize,
TRUE);
ldi = len ? (struct ld_info *)((char *)ldi + len) : 0;
@@ -1045,7 +969,122 @@ void GC_register_dynamic_libraries()
}
#endif /* RS6000 */
+#ifdef DARWIN
+
+#include <mach-o/dyld.h>
+#include <mach-o/getsect.h>
+
+/*#define DARWIN_DEBUG*/
+
+const static struct {
+ const char *seg;
+ const char *sect;
+} GC_dyld_sections[] = {
+ { SEG_DATA, SECT_DATA },
+ { SEG_DATA, SECT_BSS },
+ { SEG_DATA, SECT_COMMON }
+};
+
+#ifdef DARWIN_DEBUG
+static const char *GC_dyld_name_for_hdr(struct mach_header *hdr) {
+ unsigned long i,c;
+ c = _dyld_image_count();
+ for(i=0;i<c;i++) if(_dyld_get_image_header(i) == hdr)
+ return _dyld_get_image_name(i);
+ return NULL;
+}
+#endif
+
+/* This should never be called by a thread holding the lock */
+static void GC_dyld_image_add(struct mach_header* hdr, unsigned long slide) {
+ unsigned long start,end,i;
+ const struct section *sec;
+ for(i=0;i<sizeof(GC_dyld_sections)/sizeof(GC_dyld_sections[0]);i++) {
+ sec = getsectbynamefromheader(
+ 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_printf4("Adding section at %p-%p (%lu bytes) from image %s\n",
+ start,end,sec->size,GC_dyld_name_for_hdr(hdr));
+# 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(struct mach_header* hdr, unsigned long slide) {
+ unsigned long start,end,i;
+ const struct section *sec;
+ for(i=0;i<sizeof(GC_dyld_sections)/sizeof(GC_dyld_sections[0]);i++) {
+ sec = getsectbynamefromheader(
+ 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_printf4("Removing section at %p-%p (%lu bytes) from image %s\n",
+ start,end,sec->size,GC_dyld_name_for_hdr(hdr));
+# endif
+ GC_remove_roots((char*)start,(char*)end);
+ }
+# ifdef DARWIN_DEBUG
+ GC_print_static_roots();
+# endif
+}
+void GC_register_dynamic_libraries() {
+ /* 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. */
+
+void GC_init_dyld() {
+ static GC_bool initialized = FALSE;
+
+ if(initialized) return;
+
+# ifdef DARWIN_DEBUG
+ GC_printf0("Forcing full bind of GC code...\n");
+# endif
+ if(!_dyld_bind_fully_image_containing_address((unsigned long*)GC_malloc))
+ GC_abort("_dyld_bind_fully_image_containing_addres failed");
+
+# ifdef DARWIN_DEBUG
+ GC_printf0("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 existing and all future libraries
+ */
+
+ _dyld_register_func_for_add_image(GC_dyld_image_add);
+ _dyld_register_func_for_remove_image(GC_dyld_image_remove);
+ initialized = TRUE;
+}
+
+#define HAVE_REGISTER_MAIN_STATIC_DATA
+GC_bool GC_register_main_static_data()
+{
+ /* Already done through dyld callbacks */
+ return FALSE;
+}
+
+#endif /* DARWIN */
#else /* !DYNAMIC_LOADING */
@@ -1093,4 +1132,15 @@ void GC_register_dynamic_libraries(){}
int GC_no_dynamic_loading;
#endif /* !PCR */
+
#endif /* !DYNAMIC_LOADING */
+
+#ifndef HAVE_REGISTER_MAIN_STATIC_DATA
+
+/* Do we need to separately register the main static data segment? */
+GC_bool GC_register_main_static_data()
+{
+ return TRUE;
+}
+#endif /* HAVE_REGISTER_MAIN_STATIC_DATA */
+