[Wisp-cvs] wisp/users/dig elf.py,1.9,1.10 linkie.py,1.9,1.10 makehello.py,1.7,1.8

[<di...@us...>]

Update of /cvsroot/wisp/wisp/users/dig
In directory sc8-pr-cvs1:/tmp/cvs-serv2245

Modified Files:
	elf.py linkie.py makehello.py 
Log Message:
advanced makehello.py a bit

Index: elf.py
===================================================================
RCS file: /cvsroot/wisp/wisp/users/dig/elf.py,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -d -r1.9 -r1.10
--- elf.py	12 Feb 2003 23:05:08 -0000	1.9
+++ elf.py	15 Feb 2003 22:17:16 -0000	1.10
@@ -364,20 +364,22 @@
     h.emit_tetra_sum([name + '/alignment'])
     return h
 
-def make_ELF32_sheader (byte_order, name):
-    h = Linkie(byte_order)
-    h.align(4)
-    h.emit_tetra_sum(['.shstr/strings/' + name])
-    h.emit_tetra_sum([name + '/sh_type'])
-    h.emit_tetra_sum([name + '/sh_flags'])
-    h.emit_tetra_sum([name])
-    h.emit_tetra_sum([name + '/offset'])
-    h.emit_tetra_sum([name + '/sh_size'])
-    h.emit_tetra_sum([name + '/sh_link'])
-    h.emit_tetra_sum([name + '/sh_info'])
-    h.emit_tetra_sum([name + '/alignment'])
-    h.emit_tetra_sum([name + '/sh_entsize'])
-    return h
+def make_ELF32_shtable (byte_order, names):
+    t = Linkie(byte_order)
+    t.align(4)
+    t.emit_string('\0' * 40) # the null entry
+    for name in names:
+        t.emit_tetra_sum(['.shstr/strings/' + name])
+        t.emit_tetra_sum([name + '/sh_type'])
+        t.emit_tetra_sum([name + '/sh_flags'])
+        t.emit_tetra_sum([name])
+        t.emit_tetra_sum([name + '/offset'])
+        t.emit_tetra_sum([name + '/sh_size'])
+        t.emit_tetra_sum([name + '/sh_link'])
+        t.emit_tetra_sum([name + '/sh_info'])
+        t.emit_tetra_sum([name + '/alignment'])
+        t.emit_tetra_sum([name + '/sh_entsize'])
+    return t
 
 # Thoughts of generating ELF32 files
 #   * In ELF parlance, linker notes are called relocations.

Index: linkie.py
===================================================================
RCS file: /cvsroot/wisp/wisp/users/dig/linkie.py,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -d -r1.9 -r1.10
--- linkie.py	15 Feb 2003 15:42:52 -0000	1.9
+++ linkie.py	15 Feb 2003 22:17:16 -0000	1.10
@@ -58,6 +58,8 @@
         Places the specified bytes to the byte collector."""
         if this._skipped <> 0: raise "Events out of order", this
         this._binary.fromstring(s)
+    def from_array (this, a):
+        this._binary.extend(a)
 
     def add_byte (this, ofs, value):
         this._binary[ofs] = chr(ord(this._binary[ofs]) + value)
@@ -282,6 +284,6 @@
                     if rnotes.has_key(offset):
                         for typ, arg in rnotes[offset]:
                             print ' ' * (14 + (offset & 15) * 3) + \
-                                  "`'-" * abs(typ) + arg
+                                  "``-" * abs(typ) + arg
                 start = stop
             row += 16

Index: makehello.py
===================================================================
RCS file: /cvsroot/wisp/wisp/users/dig/makehello.py,v
retrieving revision 1.7
retrieving revision 1.8
diff -u -d -r1.7 -r1.8
--- makehello.py	15 Feb 2003 15:35:30 -0000	1.7
+++ makehello.py	15 Feb 2003 22:17:16 -0000	1.8
@@ -33,16 +33,99 @@
 data.place_symbol('message')
 data.emit_string('Hello, world!\n')
 
+def infer_by_prefix (name, dict):
+    for l in range(len(name), -1, -1):
+        prefix = name[:l]
+        try: return dict[prefix]
+        except: pass
+    return None
+def guess_shtype (name):
+    return infer_by_prefix(name, {'': SHT.PROGBITS,
+                                  '.bss': SHT.NOBITS,
+                                  '.note': SHT.NOTE,
+                                  '.shstr': SHT.STRTAB})
+def guess_ptype (name):
+    return infer_by_prefix(name, {'': PT.LOAD,
+                                  '.note': PT.NOTE})
+def guess_flags (name):
+    return infer_by_prefix(name, {'':         'rw--',
+                                  '.bss':     'rw--',
+                                  '.comment': '----',
+                                  '.data':    'rw--',
+                                  '.debug':   '----',
+                                  '.line':    '----',
+                                  '.note':    '----',
+                                  '.rodata':  'r---',
+                                  '.shstr':   '---s',
+                                  '.text':    'r-x-'})
+def guess_shflags (name):
+    flags = guess_flags(name)
+    sh_flags = 0
+    if 'r' in flags: sh_flags |= SHF.ALLOC
+    if 'w' in flags: sh_flags |= SHF.ALLOC | SHF.WRITE
+    if 'x' in flags: sh_flags |= SHF.ALLOC | SHF.EXECINSTR
+    if 's' in flags: sh_flags |= SHF.STRINGS
+    return sh_flags
+def guess_pflags (name):
+    flags = guess_flags(name)
+    p_flags = 0
+    if 'r' in flags: p_flags |= PF.R
+    if 'w' in flags: p_flags |= PF.W
+    if 'x' in flags: p_flags |= PF.X
+    return p_flags
+
+symbols = {}
+
+shstr = Linkie('<')
+shstr.emit_byte(0)
+symbols['.shstr/strings/.text'] = shstr.filesz()
+shstr.emit_string('.text\0')
+symbols['.shstr/strings/.data'] = shstr.filesz()
+shstr.emit_string('.data\0')
+symbols['.shstr/strings/.shstr'] = shstr.filesz()
+shstr.emit_string('.shstr\0')
+
 hello = Linkie('<')
-memory_boundary = 0x8048000
+memory_boundary = 0x8048000 # must be at page boundary
 hello.extend(make_ELF32_header('<'))
-symbols = {}
 symbols['elf/type'] = ET.EXEC
 symbols['elf/machine'] = EM.I386
 symbols['elf/flags'] = 0 # no flags for ia386
-program_header_table = make_ELF32_pheader('<', '.text')
+program_header_table = make_ELF32_pheader('<', '.text') + \
+                       make_ELF32_pheader('<', '.data')
 symbols['elf/phoff'] = hello.extend(program_header_table)
-# process the text segment
-symbols['.text/offset'] = hello.extend(code)
+symbols['elf/phnum'] = 2
+# process the segments
+for name, section in (('.text', code), ('.data', data), ('.shstr', shstr)):
+    alignment = section.get_alignment()
+    symbols[name + '/alignment'] = alignment
+    hello.align(min(alignment, 0x1000))
+    offset = hello.filesz()
+    address = memory_boundary | (offset & 0xFFF)
+    # take into account alignments larger than a page
+    address = (address + alignment - 1) & ~(alignment - 1)
+    symbols[name] = address
+    symbols[name + '/offset'] = offset
+    symbols[name + '/memsz'] = section.memsz()
+    symbols[name + '/filesz'] = section.filesz()
+    symbols[name + '/sh_size'] = section.filesz()
+    symbols[name + '/sh_type'] = guess_shtype(name)
+    symbols[name + '/sh_info'] = 0
+    symbols[name + '/sh_flags'] = guess_shflags(name)
+    symbols[name + '/p_flags'] = guess_pflags(name)
+    symbols[name + '/p_type'] = guess_ptype(name)
+    data = section.get_file()
+    hello.from_array(data)
+    for symbol, value in section.get_symbols():
+        symbols[symbol] = address + value
+        hello.place_symbol(symbol, offset + value) # for dump to work nicely
+    memory_boundary += section.memsz()
+    memory_boundary = (memory_boundary + 0xFFF) & ~0xFFF
+
+# create section header table
+section_header_table = make_ELF32_shtable('<', ['.text', '.data', '.shstr'])
+symbols['elf/shoff'] = hello.extend(section_header_table)
+symbols['elf/shnum'] = 4
+symbols['elf/shstrndx'] = 3
 hello.link(symbols)
 hello.dump()