tools: create a new tool for more efficient jffs2 padding

SVN-Revision: 27355

1 files changed, 155 insertions, 0 deletions

diff --git a/tools/padjffs2/src/padjffs2.c b/tools/padjffs2/src/padjffs2.c
new file mode 100644
index 0000000..679992d
--- /dev/null
+++ b/tools/padjffs2/src/padjffs2.c
@@ -0,0 +1,155 @@
+/*
+ * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+static char *progname;
+static unsigned char eof_mark[4] = {0xde, 0xad, 0xc0, 0xde};
+
+#define ERR(fmt, ...) do { \
+	fflush(0); \
+	fprintf(stderr, "[%s] *** error: " fmt "\n", \
+			progname, ## __VA_ARGS__ ); \
+} while (0)
+
+#define ERRS(fmt, ...) do { \
+	int save = errno; \
+	fflush(0); \
+	fprintf(stderr, "[%s] *** error: " fmt ", %s\n", \
+			progname, ## __VA_ARGS__, strerror(save)); \
+} while (0)
+
+#define BUF_SIZE	(64 * 1024)
+#define ALIGN(_x,_y)	(((_x) + ((_y) - 1)) & ~((_y) - 1))
+
+static int pad_image(char *name, uint32_t pad_mask)
+{
+	char *buf;
+	int fd;
+	ssize_t in_len;
+	ssize_t out_len;
+	int ret = -1;
+
+	buf = malloc(BUF_SIZE);
+	if (!buf) {
+		ERR("No memory for buffer");
+		goto out;
+	}
+
+	fd = open(name, O_RDWR);
+	if (fd < 0) {
+		ERRS("Unable to open %s", name);
+		goto free_buf;
+	}
+
+	in_len = lseek(fd, 0, SEEK_END);
+	if (in_len < 0)
+		goto close;
+
+	memset(buf, '\xff', BUF_SIZE);
+
+	out_len = in_len;
+	while (pad_mask) {
+		uint32_t mask;
+		ssize_t t;
+		int i;
+
+		for (i = 10; i < 32; i++) {
+			mask = 1UL << i;
+			if (pad_mask & mask)
+				break;
+		}
+
+		in_len = ALIGN(in_len, mask);
+
+		for (i = 10; i < 32; i++) {
+			mask = 1UL << i;
+			if ((in_len & (mask - 1)) == 0)
+				pad_mask &= ~mask;
+		}
+
+		printf("padding image to %08x\n", in_len);
+
+		while (out_len < in_len) {
+			ssize_t len;
+
+			len = in_len - out_len;
+			if (len > BUF_SIZE)
+				len = BUF_SIZE;
+
+			t = write(fd, buf, len);
+			if (t != len) {
+				ERRS("Unable to write to %s", name);
+				goto close;
+			}
+
+			out_len += len;
+		}
+
+		/* write out the JFFS end-of-filesystem marker */
+		t = write(fd, eof_mark, 4);
+		if (t != 4) {
+			ERRS("Unable to write to %s", name);
+			goto close;
+		}
+		out_len += 4;
+	}
+
+	ret = 0;
+
+close:
+	close(fd);
+free_buf:
+	free(buf);
+out:
+	return ret;
+}
+
+int main(int argc, char* argv[])
+{
+	uint32_t pad_mask;
+	int ret = EXIT_FAILURE;
+	int err;
+	int i;
+
+	progname = basename(argv[0]);
+
+	if (argc < 2) {
+		fprintf(stderr,
+			"Usage: %s file [pad0] [pad1] [padN]\n",
+			progname);
+		goto out;
+	}
+
+	pad_mask = 0;
+	for (i = 2; i < argc; i++)
+		pad_mask |= strtoul(argv[i], NULL, 0) * 1024;
+
+	if (pad_mask == 0)
+		pad_mask = (4 * 1024) | (8 * 1024) | (64 * 1024) |
+			   (128 * 1024);
+
+	err = pad_image(argv[1], pad_mask);
+	if (err)
+		goto out;
+
+	ret = EXIT_SUCCESS;
+
+out:
+	return ret;
+}