+ int nread;
+
+ if ((abfd->flags & BFD_IN_MEMORY) != 0)
+ {
+ struct bfd_in_memory *bim;
+ bfd_size_type get;
+
+ bim = (struct bfd_in_memory *) abfd->iostream;
+ get = size * nitems;
+ if (abfd->where + get > bim->size)
+ {
+ get = bim->size - abfd->where;
+ bfd_set_error (bfd_error_file_truncated);
+ }
+ memcpy (ptr, bim->buffer + abfd->where, get);
+ abfd->where += get;
+ return get;
+ }
+
+ nread = real_read (ptr, 1, (size_t)(size*nitems), bfd_cache_lookup(abfd));
+#ifdef FILE_OFFSET_IS_CHAR_INDEX
+ if (nread > 0)
+ abfd->where += nread;
+#endif
+
+ /* Set bfd_error if we did not read as much data as we expected.
+
+ If the read failed due to an error set the bfd_error_system_call,
+ else set bfd_error_file_truncated.
+
+ A BFD backend may wish to override bfd_error_file_truncated to
+ provide something more useful (eg. no_symbols or wrong_format). */
+ if (nread < (int)(size * nitems))
+ {
+ if (ferror (bfd_cache_lookup (abfd)))
+ bfd_set_error (bfd_error_system_call);
+ else
+ bfd_set_error (bfd_error_file_truncated);
+ }
+
+ return nread;
+}
+
+/* The window support stuff should probably be broken out into
+ another file.... */
+/* The idea behind the next and refcount fields is that one mapped
+ region can suffice for multiple read-only windows or multiple
+ non-overlapping read-write windows. It's not implemented yet
+ though. */
+struct _bfd_window_internal {
+ struct _bfd_window_internal *next;
+ PTR data;
+ bfd_size_type size;
+ int refcount : 31; /* should be enough... */
+ unsigned mapped : 1; /* 1 = mmap, 0 = malloc */
+};
+
+void
+bfd_init_window (windowp)
+ bfd_window *windowp;
+{
+ windowp->data = 0;
+ windowp->i = 0;
+ windowp->size = 0;
+}
+
+#undef HAVE_MPROTECT /* code's not tested yet */
+
+#if HAVE_MMAP || HAVE_MPROTECT || HAVE_MADVISE
+#include <sys/types.h>
+#include <sys/mman.h>
+#endif
+
+#ifndef MAP_FILE
+#define MAP_FILE 0
+#endif
+
+static int debug_windows;
+
+/* Currently, if USE_MMAP is undefined, none if the window stuff is
+ used. Okay, so it's mis-named. At least the command-line option
+ "--without-mmap" is more obvious than "--without-windows" or some
+ such. */
+#ifdef USE_MMAP
+
+void
+bfd_free_window (windowp)
+ bfd_window *windowp;
+{
+ bfd_window_internal *i = windowp->i;
+ windowp->i = 0;
+ windowp->data = 0;
+ if (i == 0)
+ return;
+ i->refcount--;
+ if (debug_windows)
+ fprintf (stderr, "freeing window @%p<%p,%lx,%p>\n",
+ windowp, windowp->data, windowp->size, windowp->i);
+ if (i->refcount != 0)
+ return;
+
+ if (i->mapped)
+ {
+#ifdef HAVE_MMAP
+ munmap (i->data, i->size);
+ goto no_free;
+#else
+ abort ();
+#endif
+ }
+#ifdef HAVE_MPROTECT
+ mprotect (i->data, i->size, PROT_READ | PROT_WRITE);
+#endif
+ free (i->data);
+#ifdef HAVE_MMAP
+ no_free:
+#endif
+ i->data = 0;
+ /* There should be no more references to i at this point. */
+ free (i);
+}
+#endif
+
+static int ok_to_map = 1;
+
+boolean
+bfd_get_file_window (abfd, offset, size, windowp, writable)
+ bfd *abfd;
+ file_ptr offset;
+ bfd_size_type size;
+ bfd_window *windowp;
+ boolean writable;
+{
+ static size_t pagesize;
+ bfd_window_internal *i = windowp->i;
+ size_t size_to_alloc = size;
+
+#ifndef USE_MMAP
+ abort ();
+#endif
+
+ if (debug_windows)
+ fprintf (stderr, "bfd_get_file_window (%p, %6ld, %6ld, %p<%p,%lx,%p>, %d)",
+ abfd, (long) offset, (long) size,
+ windowp, windowp->data, windowp->size, windowp->i,
+ writable);
+
+ /* Make sure we know the page size, so we can be friendly to mmap. */
+ if (pagesize == 0)
+ pagesize = getpagesize ();
+ if (pagesize == 0)
+ abort ();
+
+ if (i == 0)
+ {
+ windowp->i = i = (bfd_window_internal *) bfd_zmalloc (sizeof (bfd_window_internal));
+ if (i == 0)
+ return false;
+ i->data = 0;
+ }
+#ifdef HAVE_MMAP
+ if (ok_to_map
+ && (i->data == 0 || i->mapped == 1)
+ && (abfd->flags & BFD_IN_MEMORY) == 0)
+ {
+ file_ptr file_offset, offset2;
+ size_t real_size;
+ int fd;
+ FILE *f;
+
+ /* Find the real file and the real offset into it. */
+ while (abfd->my_archive != NULL)
+ {
+ offset += abfd->origin;
+ abfd = abfd->my_archive;
+ }
+ f = bfd_cache_lookup (abfd);
+ fd = fileno (f);
+
+ /* Compute offsets and size for mmap and for the user's data. */
+ offset2 = offset % pagesize;
+ if (offset2 < 0)
+ abort ();
+ file_offset = offset - offset2;
+ real_size = offset + size - file_offset;
+ real_size = real_size + pagesize - 1;
+ real_size -= real_size % pagesize;
+
+ /* If we're re-using a memory region, make sure it's big enough. */
+ if (i->data && i->size < size)
+ {
+ munmap (i->data, i->size);
+ i->data = 0;
+ }
+ i->data = mmap (i->data, real_size,
+ writable ? PROT_WRITE | PROT_READ : PROT_READ,
+ (writable
+ ? MAP_FILE | MAP_PRIVATE
+ : MAP_FILE | MAP_SHARED),
+ fd, file_offset);
+ if (i->data == (PTR) -1)
+ {
+ /* An error happened. Report it, or try using malloc, or
+ something. */
+ bfd_set_error (bfd_error_system_call);
+ i->data = 0;
+ windowp->data = 0;
+ if (debug_windows)
+ fprintf (stderr, "\t\tmmap failed!\n");
+ return false;
+ }
+ if (debug_windows)
+ fprintf (stderr, "\n\tmapped %ld at %p, offset is %ld\n",
+ (long) real_size, i->data, (long) offset2);
+ i->size = real_size;
+ windowp->data = (PTR) ((bfd_byte *) i->data + offset2);
+ windowp->size = size;
+ i->mapped = 1;
+ return true;
+ }
+ else if (debug_windows)
+ {
+ if (ok_to_map)
+ fprintf (stderr, "not mapping: data=%lx mapped=%d\n",
+ (unsigned long) i->data, (int) i->mapped);
+ else
+ fprintf (stderr, "not mapping: env var not set\n");
+ }
+#else
+ ok_to_map = 0;
+#endif
+
+#ifdef HAVE_MPROTECT
+ if (!writable)
+ {
+ size_to_alloc += pagesize - 1;
+ size_to_alloc -= size_to_alloc % pagesize;
+ }
+#endif
+ if (debug_windows)
+ fprintf (stderr, "\n\t%s(%6ld)",
+ i->data ? "realloc" : " malloc", (long) size_to_alloc);
+ i->data = (PTR) bfd_realloc (i->data, size_to_alloc);
+ if (debug_windows)
+ fprintf (stderr, "\t-> %p\n", i->data);
+ i->refcount = 1;
+ if (i->data == NULL)
+ {
+ if (size_to_alloc == 0)
+ return true;
+ bfd_set_error (bfd_error_no_memory);
+ return false;
+ }
+ if (bfd_seek (abfd, offset, SEEK_SET) != 0)
+ return false;
+ i->size = bfd_read (i->data, size, 1, abfd);
+ if (i->size != size)
+ return false;
+ i->mapped = 0;
+#ifdef HAVE_MPROTECT
+ if (!writable)
+ {
+ if (debug_windows)
+ fprintf (stderr, "\tmprotect (%p, %ld, PROT_READ)\n", i->data,
+ (long) i->size);
+ mprotect (i->data, i->size, PROT_READ);
+ }
+#endif
+ windowp->data = i->data;
+ windowp->size = i->size;
+ return true;
projects / binutils.git / blobdiff