1 files changed, 109 insertions, 0 deletions
diff --git a/liblogfs/format.c b/liblogfs/format.c
new file mode 100644
index 00000000..f270c84f
--- /dev/null
+++ b/liblogfs/format.c
@@ -0,0 +1,109 @@
+#include "lib9.h"
+#include "logfs.h"
+#include "local.h"
+#include "mp.h"
+#include "libsec.h"
+
+char *
+logfsformat(LogfsLowLevel *ll, long base, long limit, long bootsize, int trace)
+{
+	long bootblocksdone, logblocksdone;
+	long u;
+	long baseblock, limitblock, bootblocks, sizeinblocks;
+	int magicfound;
+	void *llsave;
+
+	if(trace > 1)
+		print("logfsformat: base %ld limit %ld bootsize %lud\n", base, limit, bootsize);
+
+	if((*ll->getopenstatus)(ll))
+		return Eperm;
+
+	if(!(*ll->calcformat)(ll, base, limit, bootsize, &baseblock, &limitblock, &bootblocks))
+		return Ebadarg;
+
+	if(trace > 0)
+		print("logfsformat: baseblock %ld limitblock %ld bootblocks %ld\n", baseblock, limitblock, bootblocks);
+
+	bootblocksdone = 0;
+	logblocksdone = 0;
+	/*
+	 * we need to create some fs blocks, and some boot blocks
+	 * the number of boot blocks is fixed; the number of fs blocks
+	 * occupies the remainder
+	 * the layout is randomised to:
+	 * 1) test the software
+	 * 2) spread wear around if a lot of format commands are issued by
+	 *     the bootloader
+	 */
+
+	sizeinblocks = limitblock - baseblock;
+
+	for(u = 0; u < sizeinblocks; u++) {
+		int r;
+		uchar tag;
+		long path;
+		LogfsLowLevelReadResult e;
+		char *errmsg;
+		int markedbad;
+
+		if(trace > 1)
+			print("block %lud:", u);
+		llsave = nil;
+		errmsg = (*ll->getblockstatus)(ll, u + baseblock, &magicfound, &llsave, &e);
+		if(errmsg)
+			return errmsg;
+		if(e == LogfsLowLevelReadResultBad) {
+			if(trace > 1)
+				print(" marked bad\n");
+			continue;
+		}
+		errmsg = (*ll->eraseblock)(ll, u + baseblock, nil, &markedbad);
+		if(errmsg)
+			return errmsg;
+		if(markedbad) {
+			if(trace > 1)
+				print(" marked bad\n");
+			continue;
+		}
+		if(e != LogfsLowLevelReadResultHardError && magicfound) {
+			if(trace > 1)
+				print(" previously formatted");
+		}
+		r = rand() % (sizeinblocks - u);
+		if(bootblocksdone < bootblocks && r < (bootblocks - bootblocksdone)) {
+			tag = LogfsTboot;
+			path = mkdatapath(bootblocksdone, 0);
+		}
+		else {
+			tag = LogfsTnone;
+			path = ~0;
+		}
+		if(trace > 1)
+			print(" tag %s path %ld", logfstagname(tag), path);
+		errmsg = (*ll->formatblock)(ll, u + baseblock, tag, path, baseblock, sizeinblocks, 1, &bootblocks, llsave, &markedbad);
+		logfsfreemem(llsave);
+		if(errmsg)
+			return errmsg;
+		if(markedbad) {
+			if(trace > 1)
+				print(" marked bad\n");
+			continue;
+		}
+		switch(tag) {
+		case LogfsTboot:
+			bootblocksdone++;
+			break;
+		case LogfsTnone:
+			logblocksdone++;
+			break;
+		}
+		if(trace > 1)
+			print("\n");
+	}
+	if(bootblocksdone < bootblocks)
+		return "not enough capacity left for boot";
+	if(trace > 0)
+		print("log blocks %lud\n", logblocksdone);
+	return nil;
+}