2007-10-14  Robert Millan  <address@hidden>

	* loader/i386/pc/multiboot.c (grub_multiboot_load_elf32): When loading
	ELF segments, use a macro for arbitrarily accessing any of them instead
	of preparing a pointer that allows access to one at a time.
	(grub_multiboot_load_elf64): Likewise.

diff -ur grub2/loader/i386/pc/multiboot.c grub2.phdr_array/loader/i386/pc/multiboot.c
--- grub2/loader/i386/pc/multiboot.c	2007-07-25 21:29:24.000000000 +0200
+++ grub2.phdr_array/loader/i386/pc/multiboot.c	2007-10-14 15:32:37.000000000 +0200
@@ -94,7 +94,7 @@
 grub_multiboot_load_elf32 (grub_file_t file, void *buffer)
 {
   Elf32_Ehdr *ehdr = (Elf32_Ehdr *) buffer;
-  Elf32_Phdr *phdr;
+  void *phdr_base;
   int i;
 
   if (ehdr->e_ident[EI_CLASS] != ELFCLASS32)
@@ -112,35 +112,38 @@
   
   entry = ehdr->e_entry;
   
+  phdr_base = (void *) buffer + ehdr->e_phoff;
+#define phdr(i)		((Elf32_Phdr *) (phdr_base + (i) * ehdr->e_phentsize))
+
   /* Load every loadable segment in memory.  */
   for (i = 0; i < ehdr->e_phnum; i++)
     {
-      phdr = (Elf32_Phdr *) ((char *) buffer + ehdr->e_phoff
-			     + i * ehdr->e_phentsize);
-      if (phdr->p_type == PT_LOAD)
+      if (phdr(i)->p_type == PT_LOAD)
         {
           /* The segment should fit in the area reserved for the OS.  */
-          if ((phdr->p_paddr < grub_os_area_addr)
-              || (phdr->p_paddr + phdr->p_memsz
+          if ((phdr(i)->p_paddr < grub_os_area_addr)
+              || (phdr(i)->p_paddr + phdr(i)->p_memsz
 		  > grub_os_area_addr + grub_os_area_size))
 	    return grub_error (GRUB_ERR_BAD_OS,
 			       "segment doesn't fit in memory reserved for the OS");
 
-          if (grub_file_seek (file, (grub_off_t) phdr->p_offset)
+          if (grub_file_seek (file, (grub_off_t) phdr(i)->p_offset)
 	      == (grub_off_t) -1)
 	    return grub_error (GRUB_ERR_BAD_OS,
 			       "invalid offset in program header");
 	  
-          if (grub_file_read (file, (void *) phdr->p_paddr, phdr->p_filesz)
-              != (grub_ssize_t) phdr->p_filesz)
+          if (grub_file_read (file, (void *) phdr(i)->p_paddr, phdr(i)->p_filesz)
+              != (grub_ssize_t) phdr(i)->p_filesz)
 	    return grub_error (GRUB_ERR_BAD_OS,
 			       "couldn't read segment from file");
 
-          if (phdr->p_filesz < phdr->p_memsz)
-            grub_memset ((char *) phdr->p_paddr + phdr->p_filesz, 0,
-			 phdr->p_memsz - phdr->p_filesz);
+          if (phdr(i)->p_filesz < phdr(i)->p_memsz)
+            grub_memset ((char *) phdr(i)->p_paddr + phdr(i)->p_filesz, 0,
+			 phdr(i)->p_memsz - phdr(i)->p_filesz);
         }
     }
+
+#undef phdr
   
   return grub_errno;
 }
@@ -158,7 +161,7 @@
 grub_multiboot_load_elf64 (grub_file_t file, void *buffer)
 {
   Elf64_Ehdr *ehdr = (Elf64_Ehdr *) buffer;
-  Elf64_Phdr *phdr;
+  void *phdr_base;
   int i;
 
   if (ehdr->e_ident[EI_CLASS] != ELFCLASS64)
@@ -186,39 +189,42 @@
 
   entry = ehdr->e_entry;
 
+  phdr_base = (void *) buffer + ehdr->e_phoff;
+#define phdr(i)		((Elf64_Phdr *) (phdr_base + (i) * ehdr->e_phentsize))
+
   /* Load every loadable segment in memory.  */
   for (i = 0; i < ehdr->e_phnum; i++)
     {
-      phdr = (Elf64_Phdr *) ((char *) buffer + ehdr->e_phoff
-			     + i * ehdr->e_phentsize);
-      if (phdr->p_type == PT_LOAD)
+      if (phdr(i)->p_type == PT_LOAD)
         {
           /* The segment should fit in the area reserved for the OS.  */
-          if ((phdr->p_paddr < (grub_uint64_t) grub_os_area_addr)
-              || (phdr->p_paddr + phdr->p_memsz
+          if ((phdr(i)->p_paddr < (grub_uint64_t) grub_os_area_addr)
+              || (phdr(i)->p_paddr + phdr(i)->p_memsz
 		  > ((grub_uint64_t) grub_os_area_addr
 		     + (grub_uint64_t) grub_os_area_size)))
 	    return grub_error (GRUB_ERR_BAD_OS,
 			       "segment doesn't fit in memory reserved for the OS");
 	  
-	  if (grub_file_seek (file, (grub_off_t) phdr->p_offset)
+	  if (grub_file_seek (file, (grub_off_t) phdr(i)->p_offset)
 	      == (grub_off_t) -1)
 	    return grub_error (GRUB_ERR_BAD_OS,
 			       "invalid offset in program header");
 
-	  if (grub_file_read (file, (void *) ((grub_uint32_t) phdr->p_paddr),
-			      phdr->p_filesz)
-              != (grub_ssize_t) phdr->p_filesz)
+	  if (grub_file_read (file, (void *) ((grub_uint32_t) phdr(i)->p_paddr),
+			      phdr(i)->p_filesz)
+              != (grub_ssize_t) phdr(i)->p_filesz)
 	    return grub_error (GRUB_ERR_BAD_OS,
 			       "couldn't read segment from file");
 	  
-          if (phdr->p_filesz < phdr->p_memsz)
-	    grub_memset (((char *) ((grub_uint32_t) phdr->p_paddr)
-			  + phdr->p_filesz),
+          if (phdr(i)->p_filesz < phdr(i)->p_memsz)
+	    grub_memset (((char *) ((grub_uint32_t) phdr(i)->p_paddr)
+			  + phdr(i)->p_filesz),
 			 0,
-			 phdr->p_memsz - phdr->p_filesz);
+			 phdr(i)->p_memsz - phdr(i)->p_filesz);
         }
     }
+
+#undef phdr
   
   return grub_errno;
 }