Changeset 490 for Whitix/branches/hybrid

Timestamp:

05/13/08 20:10:53 (5 months ago)

Author:

mwhitworth

Message:

Various cleanups, add comments.

Files:

• Whitix/branches/hybrid/kernel/module.c (modified) (9 diffs)

Whitix/branches/hybrid/kernel/module.c

@@ -37 +37 @@
 void* ModuleSymbolFind(struct Module* module, const char* symName, int type)
 {
-        int i;
+        DWORD i;
         struct ElfSymbol* symbol;
 
@@ -54 +54 @@
 
                 /* Handle data? */
-                return symbol->symValue;
+                return (void*)(symbol->symValue);
         }
 
@@ -153 +153 @@
 }
 
+/***********************************************************************
+ *
+ * FUNCTION: ModuleSymbolPrepare
+ *
+ * DESCRIPTION: Iterate through the symbol table and relocate them to the
+ *                              base address by altering their symValue, ready for
+ *                              ModuleSymbolResolve to update the relocations.
+ *
+ * PARAMETERS: module - the module's whose symbols are to be relocated.
+ *
+ * RETURNS: 0 on success, -ENOENT on an invalid symbol.
+ *
+ ***********************************************************************/
+
 int ModuleSymbolPrepare(struct Module* module)
 {
-        int i;
+        DWORD i;
         DWORD symSize=module->symTableSize/sizeof(struct ElfSymbol);
 
+        /* Iterate through all the symbols in the symbol table, skipping the first entry,
+         * which is a NULL symbol. */
         for (i=1; i<symSize; i++)
         {
                 struct ElfSymbol* symbol=&module->symTable[i];
+
+                /* Get the symbol's name in the string table. */
                 char* symName=module->strTable+symbol->symName;
 
                 switch (symbol->symIndex)
                 {
+                        /* The symbol is undefined, so we've got to look at the kernel
+                         * and module symbols to set its value. */
                         case STN_UNDEF:
                                 symbol->symValue=ModuleResolveKernel(symName);
@@ -178 +198 @@
                                 break;
 
+                        /* Common symbols aren't supported by the module loading code. */
                         case STN_COMMON:
                                 printf("Please recompile the module with -fno-common.\n");
                                 return -ENOENT;
 
+                        /* Just add the section base to the symbol value. */
                         default:
                                 symbol->symValue+=module->sectionHeaders[symbol->symIndex].shAddr;
@@ -190 +212 @@
 }
 
-/* TODO: Create a prepare symbols function, then remove symValue manipulation code here. */
-
 void ModuleSymbolResolve(struct Module* module, char* file, int sec)
 {
-        int i;
+        DWORD i;
         struct ElfReloc* reloc;
         struct ElfReloc* relTable=(struct ElfReloc*)(file+module->sectionHeaders[sec].shOffset);
@@ -241 +261 @@
                                 *size=module->sectionHeaders[i].shSize;
 
-                        return module->sectionHeaders[i].shAddr;
+                        return (void*)(module->sectionHeaders[i].shAddr);
                 }
         }
@@ -277 +297 @@
                 if (sectionHeaders[i].shType == SEC_TYPE_SYMTAB)
                 {
-                        module->symTable=(char*)file+sectionHeaders[i].shOffset;
+                        module->symTable=(struct ElfSymbol*)(file+sectionHeaders[i].shOffset);
                         module->symTableSize=sectionHeaders[i].shSize;
                 }
@@ -293 +313 @@
         /* Copy over the module data into a new image. */
         char* dest;
-        dest=module->loadAddr;
+        dest=(char*)module->loadAddr;
 
         for (i=0; i<elfHeader->shEntries; i++)
@@ -302 +322 @@
                 if (sectionHeaders[i].shFlags & SEC_FLAGS_EXEC)
                 {
-                        module->textAddr=dest;
+                        module->textAddr=(DWORD)dest;
                         module->textLength=sectionHeaders[i].shSize;
                 }
 
-                sectionHeaders[i].shAddr=dest;
+                sectionHeaders[i].shAddr=(DWORD)dest;
 
                 /* Unless it's a BSS section (or similar), copy the data over. */