Add deferred --image processing

The general idea and most of the code are based on the following
commits in the chromiumos flashrom tree:

Corresponding to flashrom svn r1482.

8fc0740356ca15d02fb1c65ab43b10844f148c3b
bb9049c66ca55e0dc621dd2c70b5d2cb6e5179bf
Signed-off-by: Louis Yung-Chieh Lo <yjlou@chromium.org>

and the main part:
d0ea9ed71e7f86bb8e8db2ca7c32a96de25343d8
Signed-off-by: David Hendricks <dhendrix@chromium.org>

This implementation does not defer the processing until doit(), but after the
argument parsing loop only (doit() should not contain argument checks).

This allows to specify -i and -l parameters in any order.

Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: David Hendricks <dhendrix@google.com>
diff --git a/layout.c b/layout.c
index aef520c..1f7f01a 100644
--- a/layout.c
+++ b/layout.c
@@ -41,6 +41,12 @@
 	char name[256];
 } romlayout_t;
 
+/* include_args lists arguments specified at the command line with -i. They
+ * must be processed at some point so that desired regions are marked as
+ * "included" in the rom_entries list.
+ */
+static char *include_args[MAX_ROMLAYOUT];
+static int num_include_args = 0; /* the number of valid entries. */
 static romlayout_t rom_entries[MAX_ROMLAYOUT];
 
 #if CONFIG_INTERNAL == 1 /* FIXME: Move the whole block to cbtable.c? */
@@ -156,10 +162,8 @@
 
 		if (romimages >= MAX_ROMLAYOUT) {
 			msg_gerr("Maximum number of ROM images (%i) in layout "
-				 "file reached before end of layout file.\n",
-				 MAX_ROMLAYOUT);
-			msg_gerr("Ignoring the rest of the layout file.\n");
-			break;
+				 "file reached.\n", MAX_ROMLAYOUT);
+			return 1;
 		}
 		if (2 != fscanf(romlayout, "%s %s\n", tempstr, rom_entries[romimages].name))
 			continue;
@@ -194,27 +198,80 @@
 }
 #endif
 
-int find_romentry(char *name)
+/* register an include argument (-i) for later processing */
+int register_include_arg(char *name)
+{
+	if (num_include_args >= MAX_ROMLAYOUT) {
+		msg_gerr("Too many regions included (%i).\n", num_include_args);
+		return 1;
+	}
+
+	if (name == NULL) {
+		msg_gerr("<NULL> is a bad region name.\n");
+		return 1;
+	}
+
+	include_args[num_include_args] = name;
+	num_include_args++;
+	return 0;
+}
+
+/* returns the index of the entry (or a negative value if it is not found) */
+static int find_romentry(char *name)
 {
 	int i;
 
 	if (!romimages)
 		return -1;
 
-	msg_ginfo("Looking for \"%s\"... ", name);
-
+	msg_gspew("Looking for region \"%s\"... ", name);
 	for (i = 0; i < romimages; i++) {
 		if (!strcmp(rom_entries[i].name, name)) {
 			rom_entries[i].included = 1;
-			msg_ginfo("found.\n");
+			msg_gspew("found.\n");
 			return i;
 		}
 	}
-	msg_ginfo("not found.\n");	// Not found. Error.
-
+	msg_gspew("not found.\n");
 	return -1;
 }
 
+/* process -i arguments
+ * returns 0 to indicate success, >0 to indicate failure
+ */
+int process_include_args(void)
+{
+	int i;
+	unsigned int found = 0;
+
+	if (num_include_args == 0)
+		return 0;
+
+	for (i = 0; i < num_include_args; i++) {
+		/* User has specified an area, but no layout file is loaded. */
+		if (!romimages) {
+			msg_gerr("Region requested (with -i \"%s\"), "
+				 "but no layout data is available.\n",
+				 include_args[i]);
+			return 1;
+		}
+
+		if (find_romentry(include_args[i]) < 0) {
+			msg_gerr("Invalid region specified: \"%s\"\n",
+				 include_args[i]);
+			return 1;
+		}
+		found++;
+	}
+
+	msg_ginfo("Using region%s: \"%s\"", num_include_args > 1 ? "s" : "",
+		  include_args[0]);
+	for (i = 1; i < num_include_args; i++)
+		msg_ginfo(", \"%s\"", include_args[i]);
+	msg_ginfo(".\n");
+	return 0;
+}
+
 romlayout_t *get_next_included_romentry(unsigned int start)
 {
 	int i;
@@ -248,11 +305,12 @@
 	romlayout_t *entry;
 	unsigned int size = flash->total_size * 1024;
 
-	/* If no layout file was specified or the layout file was empty, assume
-	 * that the user wants to flash the complete new image.
+	/* If no regions were specified for inclusion, assume
+	 * that the user wants to write the complete new image.
 	 */
-	if (!romimages)
+	if (num_include_args == 0)
 		return 0;
+
 	/* Non-included romentries are ignored.
 	 * The union of all included romentries is used from the new image.
 	 */
@@ -264,6 +322,7 @@
 			       size - start);
 			break;
 		}
+		/* For non-included region, copy from old content. */
 		if (entry->start > start)
 			memcpy(newcontents + start, oldcontents + start,
 			       entry->start - start);