Flashrom update from Stefan, resolve issue 21

Corresponding to flashrom svn r34 and coreboot v2 svn r2111.
diff --git a/layout.c b/layout.c
new file mode 100644
index 0000000..2219096
--- /dev/null
+++ b/layout.c
@@ -0,0 +1,170 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include "layout.h"
+#include "lbtable.h"
+#include "debug.h"
+
+char * mainboard_vendor=NULL;
+char * mainboard_part=NULL;
+int romimages=0;
+
+extern int force;
+
+#define MAX_ROMLAYOUT	16
+
+typedef struct {
+	unsigned int start;
+	unsigned int end;
+	unsigned int included;
+	char name[256];
+} romlayout_t;
+
+romlayout_t rom_entries[MAX_ROMLAYOUT];
+
+static char *def_name = "DEFAULT";
+
+
+int show_id(uint8_t *bios, int size)
+{
+	unsigned int *walk;
+
+
+	walk=(unsigned int *)(bios+size-0x10);
+	walk--; 
+	
+	if((*walk)==0 || ((*walk)&0x3ff) != 0) {
+		/* We might have an Nvidia chipset bios 
+		 * which stores the id information at a 
+		 * different location.
+		 */
+		walk=(unsigned int *)(bios+size-0x80);
+		walk--; 
+	}
+	
+	if((*walk)==0 || ((*walk)&0x3ff) != 0) {
+		printf("Flash image seems to be a legacy BIOS. Disabling checks.\n");
+		mainboard_vendor=def_name;
+		mainboard_part=def_name;
+		return 0;
+	}
+	
+	printf("LinuxBIOS image size=%d\n", *walk);
+	
+	walk--; mainboard_part=strdup((const char *)(bios+size-*walk));
+	walk--; mainboard_vendor=strdup((const char *)(bios+size-*walk));
+	printf("MANUFACTURER: %s\n", mainboard_vendor);
+	printf("MAINBOARD ID: %s\n", mainboard_part);
+	if(lb_vendor && !strcmp(mainboard_vendor, lb_vendor) && 
+	   lb_part && !strcmp(mainboard_part, lb_part)) {
+		printf ("This firmware image matches "
+		        "this motherboard.\n");
+	} else {
+		if(force) {
+			printf("WARNING: This firmware image does not "
+			"fit to this machine - forcing it.\n");
+		} else {
+			printf("ERROR: This firmware image does not "
+			"fit to this machine\nOverride with -m if"
+			"you know exactly what you are doing.\n");
+			exit(1);
+		}
+	}
+			
+	return 0;
+}
+
+int read_romlayout(char *name) 
+{
+	FILE *romlayout;
+	char tempstr[256];
+	int i;
+
+	romlayout=fopen (name, "r");
+	
+	if(!romlayout) {
+		printf("Error while opening rom layout.\n");
+		return -1;
+	}
+	
+	while(!feof(romlayout)) {
+		char *tstr1, *tstr2;
+		fscanf(romlayout,"%s %s\n", tempstr, rom_entries[romimages].name);
+#if 0
+		// fscanf does not like arbitrary comments like that :( later
+		if (tempstr[0]=='#') {
+			continue;
+		}
+#endif
+		tstr1=strtok(tempstr,":");
+		tstr2=strtok(NULL,":");
+		rom_entries[romimages].start=strtol(tstr1, (char **)NULL, 16);
+		rom_entries[romimages].end=strtol(tstr2, (char **)NULL, 16);
+		rom_entries[romimages].included=0;
+		romimages++;
+	}
+	
+	for(i=0; i<romimages; i++) {
+		printf("romlayout %08x - %08x named %s\n", 
+			rom_entries[i].start,
+			rom_entries[i].end,
+			rom_entries[i].name);
+	}
+
+	fclose(romlayout);
+	return 0;	
+}
+
+int find_romentry(char *name)
+{
+	int i;
+
+	if(!romimages) return -1;
+
+	printf("Looking for \"%s\"... ", name);
+	
+	for (i=0; i<romimages; i++) {
+		if(!strcmp(rom_entries[i].name, name)) {
+			rom_entries[i].included=1;
+			printf("found.\n");
+			return i;
+		}
+	}
+	printf("not found.\n");
+	// Not found. Error.
+	return -1;
+}
+
+int handle_romentries(uint8_t *buffer, uint8_t *content)
+{
+	int i;
+
+	// This function does not safe flash write cycles.
+	// 
+	// Also it does not cope with overlapping rom layout
+	// sections. 
+	// example:
+	// 00000000:00008fff gfxrom
+	// 00009000:0003ffff normal
+	// 00040000:0007ffff fallback
+	// 00000000:0007ffff all
+	//
+	// If you'd specify -i all the included flag of all other
+	// sections is still 0, so no changes will be made to the
+	// flash. Same thing if you specify -i normal -i all only 
+	// normal will be updated and the rest will be kept.
+
+	
+	for (i=0; i<romimages; i++) {
+		
+		if (rom_entries[i].included) 
+			continue;
+		
+		memcpy (buffer+rom_entries[i].start,
+			content+rom_entries[i].start,
+			rom_entries[i].end-rom_entries[i].start);
+	}
+
+	return 0;
+}