[MULTIBOOT2 SPEC PATCH v4 26/27] multiboot2: Generate symbol lists and disassembly file

[Hans Ulrich Niedermann]

Generate symbol lists (kernel.sym with nm and kernel.vsym
with objdump) and a complete disassembly of the finished
kernel image.

This helps with examining how the built kernel image is
actually linked and what parts of the code and data have
ended up where.

This makes the example kernel more educational.

Signed-off-by: Hans Ulrich Niedermann <address@hidden>

diff --git a/.gitignore b/.gitignore
index f6a1b7736..ba08c2911 100644
--- a/.gitignore
+++ b/.gitignore
@@ -39,7 +39,10 @@ Makefile
 /doc/*.c.texi
 /doc/*.h.texi
 /doc/kernel
+/doc/kernel.lss
 /doc/kernel.map
+/doc/kernel.sym
+/doc/kernel.vsym
 /doc/multiboot.info*
 /doc/stamp-vti
 /doc/version.texi
diff --git a/configure.ac b/configure.ac
index 6b0718451..e70da14d0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -31,8 +31,28 @@ AS_IF([test "x$host" != "x$build"], [dnl
 ])
 
 AC_PROG_CC
+AC_PROG_GREP
 AM_PROG_AS
 
+AC_ARG_VAR([NM], [nm tool])
+AC_CHECK_TOOL([NM], [nm])
+
+AC_ARG_VAR([OBJDUMP], [objdump tool])
+AC_CHECK_TOOL([OBJDUMP], [objdump])
+
+AC_ARG_VAR([SORT], [sort program])
+AC_PATH_PROG([SORT], [sort])
+
+AC_ARG_VAR([UNIQ], [uniq program])
+AC_PATH_PROG([UNIQ], [uniq])
+
+AC_ARG_VAR([SORT_U], [working sort -u program])
+# we are too lazy to figure out whether 'sort -u' works
+SORT_U="\${SORT} | \${UNIQ}"
+AC_SUBST([SORT_U])
+AC_MSG_CHECKING([for sort -u])
+AC_MSG_RESULT([${SORT_U} (lazy)])
+
 dnl Build the example Multiboot2 kernel (if possible on this host)
 kernel_boot_arch=unsupported
 kernel_ccasflags=
diff --git a/doc/Makefile.am b/doc/Makefile.am
index fe1e473c9..a382b62be 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -32,6 +32,26 @@ kernel_CFLAGS    += -save-temps=obj
 EXTRA_DIST = $(man_MANS) $(noinst_SCRIPTS) \
        $(arch_sources) $(multiboot_TEXINFOS)
 
+noinst_DATA =
+
+CLEANFILES  += kernel.lss
+noinst_DATA += kernel.lss
+kernel.lss: kernel$(EXEEXT)
+       $(OBJDUMP) -h -S kernel$(EXEEXT) > kernel.lss.new
+       mv -f kernel.lss.new kernel.lss
+
+CLEANFILES  += kernel.sym
+noinst_DATA += kernel.sym
+kernel.sym: kernel$(EXEEXT)
+       $(NM) -n kernel$(EXEEXT) | $(SORT_U) > kernel.sym.new
+       mv -f kernel.sym.new kernel.sym
+
+CLEANFILES  += kernel.vsym
+noinst_DATA += kernel.vsym
+kernel.vsym: kernel$(EXEEXT)
+       $(OBJDUMP) --syms kernel$(EXEEXT) | $(GREP) '^[0-9a-f]\{4,16\} ' | 
$(SORT_U) > kernel.vsym.new
+       mv -f kernel.vsym.new kernel.vsym
+
 # Cancel the rule %.texi -> %. This rule may confuse make to determine
 # the dependecies.
 .texi:
-- 
2.26.2