Resolve unresolved externals when loading object files.

Object files that depend on each other will cause an unresolved
external. The change lets object files load with unresolved
externals and will resolve them when the object file with the
external is loaded.

A common table of symbol strings and relocation records is maintained.
The symbol string is shared by each object file that is unresolved.
Each relocation record that references the symbol is held. The table
is a series of small blocks that compact as symbols are resolved. The
number of symbols left unresolved is typically small this design avoids
fragmentation of the heap memory.

1 files changed, 18 insertions, 24 deletions

diff --git a/wscript b/wscript
index 7ab2cbf..c58964f 100644
--- a/wscript
+++ b/wscript
@@ -17,6 +17,9 @@ def configure(conf):
     conf.env.ASCIIDOC = conf.find_program(['asciidoc.py'], mandatory = False)
     conf.env.ASCIIDOC_FLAGS = ['-b', 'html5', '-a', 'data-uri', '-a', 'icons', '-a', 'max-width=55em-a']
 
+    # hack on at the moment.
+    conf.env.GSYM_EMBEDDED = True
+
 def build(bld):
     bld.add_post_fun(rtl_post_build)
 
@@ -24,10 +27,14 @@ def build(bld):
 
     arch = bld.get_env()['RTEMS_ARCH']
 
-    bld.includes = ['.', 
+    bld.includes = ['.',
                     'libbsd/include',
                     'libbsd/include/arch/' + arch]
 
+    bld.defines = ['PACKAGE_VERSION="' + version + '"']
+    if bld.env.GSYM_EMBEDDED:
+        bld.defines += ['RTL_GSYM_EMBEDDED=1']
+
     rtl_source(bld, arch)
     rtl_liba(bld, arch)
     rtl_root_fs(bld)
@@ -39,7 +46,7 @@ def build(bld):
                   'main.c',
                   'fs-root-tarfile.o'],
         includes = bld.includes,
-        defines = ['PACKAGE_VERSION="' + version + '"'],
+        defines = bld.defines,
         use = ['rtl', 'rootfs', 'rtld-gsyms'],
         depends_on = 'gsyms')
 
@@ -72,15 +79,17 @@ def rtl_source(bld, arch):
                   'rtl-string.c',
                   'rtl-sym.c',
                   'rtl-trace.c',
+                  'rtl-unresolved.c',
                   'rtl-mdreloc-' + arch + '.c'])
 
 def rtl_liba(bld, arch):
     bld(target = 'x',
         features = 'c cstlib',
         includes = bld.includes,
+        defines = bld.defines,
         source = ['xa.c',
                   'x-long-name-to-create-gnu-extension-in-archive.c'])
-        
+
 def mmap_source(bld, includes):
     bld(target = 'mmap',
         features = 'c',
@@ -111,35 +120,20 @@ def rtl_gsyms(bld):
             import os
             sb = os.stat(src)
             if sb.st_size == 0:
+                if bld.env.GSYM_EMBEDDED:
+                    flags = '--embed'
+                else:
+                    flags = ''
                 bld(name = 'gsyms',
                     target = 'gsyms.c',
                     always = True,
-                    rule = '${NM} -g rtld | awk -f ../../mksyms.awk - > ${TGT}')
-    else:
-        open(src, 'a').close()
-    bld(target = 'rtld-gsyms',
-        features = 'c',
-        includes = bld.includes,
-        source = ['rtld-gsyms.c'],
-        depends_on = 'gsyms')
-
-def x_rtl_gsyms(bld):
-    import os.path
-    src = os.path.join(bld.get_variant_dir(), 'gsyms.c')
-    if os.path.exists(src):
-        if os.path.exists(os.path.join(bld.get_variant_dir(), 'rtld')):
-            import os
-            sb = os.stat(src)
-            if sb.st_size == 0:
-                bld(name = 'gsyms',
-                    target = 'gsyms.c',
-                    always = True,
-                    rule = '${NM} -g rtld | awk -f ../../mksyms.awk - > ${TGT}')
+                    rule = '${NM} -g rtld | awk -f ../../mksyms.awk - ' + flags + ' > ${TGT}')
     else:
         open(src, 'a').close()
     bld(target = 'rtld-gsyms',
         features = 'c',
         includes = bld.includes,
+        defines = bld.defines,
         source = ['rtld-gsyms.c'],
         depends_on = 'gsyms')