cs: on Linux record embedded boot relative to ".rackboot" section

racket/src/cs/c/Makefile.in

@@ -131,10 +131,10 @@ racket.boot: racket.so
 EMBED_DEPS = $(srcdir)/embed-boot.rkt
 
 racketcs@NOT_OSX@: raw_racketcs racket.boot $(EMBED_DEPS)
-	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @COMPRESS_COMP@ raw_racketcs racketcs $(SCHEME_INC) racket.boot
+	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @ELF_COMP@ @COMPRESS_COMP@ raw_racketcs racketcs $(SCHEME_INC) racket.boot
 
 gracketcs@NOT_OSX@: raw_gracketcs racket.boot $(EMBED_DEPS)
-	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @COMPRESS_COMP@ raw_gracketcs gracketcs $(SCHEME_INC) racket.boot
+	$(BOOTSTRAP_RACKET) $(srcdir)/embed-boot.rkt @ELF_COMP@ @COMPRESS_COMP@ raw_gracketcs gracketcs $(SCHEME_INC) racket.boot
 
 BOOT_OBJS = boot.o $(SCHEME_INC)/kernel.o rktio/librktio.a
 

racket/src/cs/c/configure

@@ -629,6 +629,7 @@ FRAMEWORK_INSTALL_DIR
 SCHEME_CONFIG_ARGS
 MAKE_BUILD_SCHEME
 SCHEME_SRC
+ELF_COMP
 COMPRESS_COMP
 CONFIGURE_RACKET_SO_COMPILE
 NOT_OSX
@@ -2734,6 +2735,7 @@ OSX="not_osx"
 NOT_OSX=""
 CONFIGURE_RACKET_SO_COMPILE=""
 COMPRESS_COMP=""
+ELF_COMP=""
 
 FRAMEWORK_INSTALL_DIR='$(libpltdir)'
 FRAMEWORK_PREFIX='@executable_path/../lib/'
@@ -3661,6 +3663,8 @@ case "$host_os" in
   linux*)
     MACH_OS=le
     LIBS="${LIBS} -lrt"
+    CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
+    ELF_COMP="--expect-elf"
     ;;
   osf1*)
     ;;
@@ -4453,6 +4457,7 @@ CPPFLAGS="$CPPFLAGS $PREFLAGS"
 
 
 
+
 
 
 makefiles="Makefile"

racket/src/cs/c/configure.ac

@@ -102,6 +102,7 @@ OSX="not_osx"
 NOT_OSX=""
 CONFIGURE_RACKET_SO_COMPILE=""
 COMPRESS_COMP=""
+ELF_COMP=""
 
 FRAMEWORK_INSTALL_DIR='$(libpltdir)'
 FRAMEWORK_PREFIX='@executable_path/../lib/'
@@ -152,6 +153,8 @@ case "$host_os" in
   linux*)
     MACH_OS=le
     LIBS="${LIBS} -lrt"
+    CPPFLAGS="${CPPFLAGS} -DELF_FIND_BOOT_SECTION"
+    ELF_COMP="--expect-elf"
     ;;
   osf1*)
     ;;
@@ -423,6 +426,7 @@ AC_SUBST(OSX)
 AC_SUBST(NOT_OSX)
 AC_SUBST(CONFIGURE_RACKET_SO_COMPILE)
 AC_SUBST(COMPRESS_COMP)
+AC_SUBST(ELF_COMP)
 AC_SUBST(SCHEME_SRC)
 AC_SUBST(MAKE_BUILD_SCHEME)
 AC_SUBST(SCHEME_CONFIG_ARGS)

racket/src/cs/c/embed-boot.rkt

@@ -5,10 +5,14 @@
          compiler/private/elf
          "adjust-compress.rkt")
 
+(define expect-elf? #f)
+
 (command-line
  #:once-each
  [("--compress") "Leave compiled code files as compressed"
   (enable-compress!)]
+ [("--expect-elf") "Record offset from ELF section"
+  (set! expect-elf? #t)]
  #:args (src-file dest-file boot-dir racket.boot)
 
  (define bstr1 (adjust-compress (file->bytes (build-path boot-dir "petite.boot"))))
@@ -51,7 +55,12 @@
           [start-pos
            ;; Success as ELF
            (ensure-executable dest-file)
-           start-pos]
+           (cond
+             [expect-elf?
+              ;; Find ".rackboot" at run time:
+              0]
+             [else
+              start-pos])]
           [else
            ;; Not ELF; just append to the end
            (copy-file src-file dest-file #t)
@@ -63,6 +72,8 @@
             (lambda (o)
               (file-position o pos)
               (write-bytes data o)))
+           (when expect-elf?
+             (error 'embed-boot "expected ELF"))
            pos])]))
 
    (define-values (i o) (open-input-output-file dest-file #:exists 'update))

racket/src/cs/c/main.c

@@ -77,6 +77,54 @@ static char *get_self_path()
 }
 #endif
 
+
+#ifdef ELF_FIND_BOOT_SECTION
+# include <elf.h>
+# include <fcntl.h>
+
+static long find_boot_section(char *me)
+{
+  int fd, i;
+  Elf64_Ehdr e;
+  Elf64_Shdr s;
+  char *strs;
+
+  fd = open(me, O_RDONLY, 0);
+  if (fd == -1) return 0;
+
+  if (read(fd, &e, sizeof(e)) == sizeof(e)) {
+    lseek(fd, e.e_shoff + (e.e_shstrndx * e.e_shentsize), SEEK_SET);
+    if (read(fd, &s, sizeof(s)) != sizeof(s)) {
+      close(fd);
+      return 0;
+    }
+
+    strs = (char *)malloc(s.sh_size);
+    lseek(fd, s.sh_offset, SEEK_SET);
+    if (read(fd, strs, s.sh_size) != s.sh_size) {
+      close(fd);
+      return 0;
+    }
+
+    for (i = 0; i < e.e_shnum; i++) {
+      lseek(fd, e.e_shoff + (i * e.e_shentsize), SEEK_SET);
+      if (read(fd, &s, sizeof(s)) != sizeof(s)) {
+        close(fd);
+        return 0;
+      }
+      if (!strcmp(strs + s.sh_name, ".rackboot")) {
+        close(fd);
+        return s.sh_offset;
+      }
+    }
+  }
+
+  close(fd);
+  return 0;
+}
+#endif
+
+
 #ifdef _MSC_VER
 static char *get_self_path()
 {
@@ -129,6 +177,16 @@ int main(int argc, char **argv)
   memcpy(&pos2, boot_file_data + boot_file_offset + 4, sizeof(pos2));
   memcpy(&pos3, boot_file_data + boot_file_offset + 8, sizeof(pos2));
 
+#ifdef ELF_FIND_BOOT_SECTION
+  {
+    long boot_offset;
+    boot_offset = find_boot_section(self);
+    pos1 += boot_offset;
+    pos2 += boot_offset;
+    pos3 += boot_offset;
+  }
+#endif
+
   racket_boot(argc, argv, self, segment_offset,
               extract_coldir(), extract_configdir(),
               pos1, pos2, pos3,