[project @ 2002-02-01 02:05:52 by sof]

[ghc-hetmet.git] / ghc / rts / Linker.c

diff --git a/ghc/rts/Linker.c b/ghc/rts/Linker.c
index 31a21db..3ed1843 100644 (file)
--- a/ghc/rts/Linker.c
+++ b/ghc/rts/Linker.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: Linker.c,v 1.78 2002/01/23 11:29:12 sewardj Exp $
+ * $Id: Linker.c,v 1.81 2002/02/01 02:05:52 sof Exp $
  *
  * (c) The GHC Team, 2000, 2001
  *
@@ -870,6 +870,33 @@ static void addSection ( ObjectCode* oc, SectionKind kind,
       and Common Object File Format Specification
       revision 5.1 January 1998
    which SimonM says comes from the MS Developer Network CDs.
+   
+   It can be found there (on older CDs), but can also be found 
+   online at:
+
+      http://www.microsoft.com/hwdev/hardware/PECOFF.asp
+
+   (this is Rev 6.0 from February 1999).
+
+   Things move, so if that fails, try searching for it via
+
+      http://www.google.com/search?q=PE+COFF+specification     
+
+   The ultimate reference for the PE format is the Winnt.h 
+   header file that comes with the Platform SDKs; as always,
+   implementations will drift wrt their documentation.
+   
+   A good background article on the PE format is Matt Pietrek's
+   March 1994 article in Microsoft System Journal (MSJ)
+   (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
+   Win32 Portable Executable File Format." The info in there
+   has recently been updated in a two part article in 
+   MSDN magazine, issues Feb and March 2002,
+   "Inside Windows: An In-Depth Look into the Win32 Portable
+   Executable File Format"
+
+   John Levine's book "Linkers and Loaders" contains useful
+   info on PE too.
 */
       
 
@@ -961,6 +988,7 @@ typedef
 /* From PE spec doc, section 4.1 */
 #define MYIMAGE_SCN_CNT_CODE             0x00000020
 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
+#define MYIMAGE_SCN_LNK_NRELOC_OVFL      0x01000000
 
 /* From PE spec doc, section 5.2.1 */
 #define MYIMAGE_REL_I386_DIR32           0x0006
@@ -1094,7 +1122,8 @@ zapTrailingAtSign ( UChar* sym )
 static int
 ocVerifyImage_PEi386 ( ObjectCode* oc )
 {
-   int i, j;
+   int i;
+   UInt32 j, noRelocs;
    COFF_header*  hdr;
    COFF_section* sectab;
    COFF_symbol*  symtab;
@@ -1137,13 +1166,15 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
       there are more than 64k relocations, despite claims to the
       contrary.  Hence this test. */
    /* fprintf(stderr, "strtab size %d\n", * (UInt32*)strtab); */
-   if (* (UInt32*)strtab > 600000) {
+#if 0
+   if ( (*(UInt32*)strtab) > 600000 ) {
       /* Note that 600k has no special significance other than being
          big enough to handle the almost-2MB-sized lumps that
          constitute HSwin32*.o. */
       belch("PEi386 object has suspiciously large string table; > 64k relocs?");
       return 0;
    }
+#endif
 
    /* No further verification after this point; only debug printing. */
    i = 0;
@@ -1207,8 +1238,23 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
       reltab = (COFF_reloc*) (
                   ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
                );
+              
+      if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
+       /* If the relocation field (a short) has overflowed, the
+        * real count can be found in the first reloc entry.
+        * 
+        * See Section 4.1 (last para) of the PE spec (rev6.0).
+        */
+        COFF_reloc* rel = (COFF_reloc*)
+                           myindex ( sizeof_COFF_reloc, reltab, 0 );
+       noRelocs = rel->VirtualAddress;
+       j = 1;
+      } else {
+       noRelocs = sectab_i->NumberOfRelocations;
+        j = 0;
+      }
 
-      for (j = 0; j < sectab_i->NumberOfRelocations; j++) {
+      for (; j < noRelocs; j++) {
          COFF_symbol* sym;
          COFF_reloc* rel = (COFF_reloc*)
                            myindex ( sizeof_COFF_reloc, reltab, j );
@@ -1218,6 +1264,7 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
                    rel->VirtualAddress );
          sym = (COFF_symbol*)
                myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
+        /* Hmm..mysterious looking offset - what's it for? SOF */
          printName ( sym->Name, strtab -10 );
          fprintf ( stderr, "'\n" );
       }
@@ -1414,9 +1461,9 @@ ocGetNames_PEi386 ( ObjectCode* oc )
          /* fprintf(stderr, "BSS      section at 0x%x\n", addr); */
       }
 
-      if (addr != NULL) {
+      if (addr != NULL ) {
          sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
-         /* fprintf(stderr,"addSymbol %p `%s'\n", addr,sname); */
+         /* fprintf(stderr,"addSymbol %p `%s \n", addr,sname);  */
          IF_DEBUG(linker, belch("addSymbol %p `%s'\n", addr,sname);)
          ASSERT(i >= 0 && i < oc->n_symbols);
          /* cstring_from_COFF_symbol_name always succeeds. */
@@ -1466,7 +1513,8 @@ ocResolve_PEi386 ( ObjectCode* oc )
    UInt32        S;
    UInt32*       pP;
 
-   int i, j;
+   int i;
+   UInt32 j, noRelocs;
 
    /* ToDo: should be variable-sized?  But is at least safe in the
       sense of buffer-overrun-proof. */
@@ -1501,7 +1549,24 @@ ocResolve_PEi386 ( ObjectCode* oc )
           || 0 == strcmp(".stabstr", sectab_i->Name))
          continue;
 
-      for (j = 0; j < sectab_i->NumberOfRelocations; j++) {
+      if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
+       /* If the relocation field (a short) has overflowed, the
+        * real count can be found in the first reloc entry.
+         *
+        * See Section 4.1 (last para) of the PE spec (rev6.0).
+        */
+        COFF_reloc* rel = (COFF_reloc*)
+                           myindex ( sizeof_COFF_reloc, reltab, 0 );
+       noRelocs = rel->VirtualAddress;
+       fprintf(stderr, "Overflown relocs: %u\n", noRelocs);
+       j = 1;
+      } else {
+       noRelocs = sectab_i->NumberOfRelocations;
+        j = 0;
+      }
+
+
+      for (; j < noRelocs; j++) {
          COFF_symbol* sym;
          COFF_reloc* reltab_j 
             = (COFF_reloc*)