+int
+open_binary(char *filename, int mode)
+{
+#ifdef LISP_FEATURE_WIN32
+ mode |= O_BINARY;
+#endif
+
+ return open(filename, mode);
+}
+
+/* Search 'filename' for an embedded core. An SBCL core has, at the
+ * end of the file, a trailer containing the size of the core (an
+ * os_vm_offset_t) and a final signature word (the lispobj
+ * CORE_MAGIC). If this trailer is found at the end of the file, the
+ * start of the core can be determined from the core size.
+ *
+ * If an embedded core is present, this returns the offset into the
+ * file to load the core from, or -1 if no core is present. */
+os_vm_offset_t
+search_for_embedded_core(char *filename)
+{
+ lispobj header;
+ os_vm_offset_t lispobj_size = sizeof(lispobj);
+ os_vm_offset_t trailer_size = lispobj_size + sizeof(os_vm_offset_t);
+ os_vm_offset_t core_size, pos;
+ int fd = -1;
+
+ if ((fd = open_binary(filename, O_RDONLY)) < 0)
+ goto lose;
+ if (lseek(fd, -lispobj_size, SEEK_END) < 0)
+ goto lose;
+ if (read(fd, &header, (size_t)lispobj_size) < lispobj_size)
+ goto lose;
+
+ if (header == CORE_MAGIC) {
+ if (lseek(fd, -trailer_size, SEEK_END) < 0)
+ goto lose;
+ if (read(fd, &core_size, sizeof(os_vm_offset_t)) < 0)
+ goto lose;
+
+ if (lseek(fd, -(core_size + trailer_size), SEEK_END) < 0)
+ goto lose;
+ pos = lseek(fd, 0, SEEK_CUR);
+
+ if (read(fd, &header, (size_t)lispobj_size) < lispobj_size)
+ goto lose;
+
+ if (header != CORE_MAGIC)
+ goto lose;
+
+ close(fd);
+ return pos;
+ }
+
+lose:
+ if (fd != -1)
+ close(fd);
+
+ return -1;
+}
+