liminix/pkgs/mtdutils/0001-mkfs.jffs2-add-graft-option.patch

From 65cefb4cffadbd3b7adb9ff4a80db2914b0da4fd Mon Sep 17 00:00:00 2001
From: Daniel Barlow <dan@telent.net>
Date: Fri, 31 Mar 2023 23:33:04 +0100
Subject: [PATCH] mkfs.jffs2: add --graft option

Allows creation of image from more than one source directory tree,
using --graft src:dest to graft new subtrees into the output. For
example

mkfs.jffs2 -r ./rootfs --graft $HOME/Pictures:/pictures

to add your photo collection into the filesystem at /pictures
without first copying it to rootfs
---
 jffsX-utils/mkfs.jffs2.c | 76 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 75 insertions(+), 1 deletion(-)

diff --git a/jffsX-utils/mkfs.jffs2.c b/jffsX-utils/mkfs.jffs2.c
index bd67634..a33f4b4 100644
--- a/jffsX-utils/mkfs.jffs2.c
+++ b/jffsX-utils/mkfs.jffs2.c
@@ -112,6 +112,14 @@ static int squash_perms = 0;
 static int fake_times = 0;
 int target_endian = __BYTE_ORDER;
 
+struct graft {
+	struct graft *next;
+	const char * source;
+	const char * dest;
+	struct stat st;
+} * grafts = 0;
+
+
 static uint32_t find_hardlink(struct filesystem_entry *e)
 {
 	struct filesystem_entry *f;
@@ -597,6 +605,16 @@ static void cleanup(struct filesystem_entry *dir)
 	}
 }
 
+static void free_grafts(struct graft *graft)
+{
+	if(graft) {
+		if(graft->next) free_grafts(graft->next);
+		free((char *)graft->source);
+		free((char *)graft);
+	}
+}
+
+
 /* Here is where we do the actual creation of the file system */
 #include "mtd/jffs2-user.h"
 
@@ -1359,6 +1377,7 @@ static void create_target_filesystem(struct filesystem_entry *root)
 static struct option long_options[] = {
 	{"pad", 2, NULL, 'p'},
 	{"root", 1, NULL, 'r'},
+	{"graft", 1, NULL, 'G'},
 	{"pagesize", 1, NULL, 's'},
 	{"eraseblock", 1, NULL, 'e'},
 	{"output", 1, NULL, 'o'},
@@ -1396,6 +1415,9 @@ static const char helptext[] =
 "                          not specified, the output is padded to the end of\n"
 "                          the final erase block\n"
 "  -r, -d, --root=DIR      Build file system from directory DIR (default: cwd)\n"
+"  -G, --graft=SOURCE:DEST Add contents of SOURCE directory at DEST in image.\n"
+"                          May be given more than once. DEST must exist in\n"
+"                          root DIR or a previous graft. \n"
 "  -s, --pagesize=SIZE     Use page size (max data node size) SIZE.\n"
 "                          Set according to target system's memory management\n"
 "                          page size (default: 4KiB)\n"
@@ -1430,6 +1452,25 @@ static const char helptext[] =
 "  -V, --version           Display version information\n"
 "  -i, --incremental=FILE  Parse FILE and generate appendage output for it\n\n";
 
+static int add_graft(const char * source, const char *dest)
+{
+	struct graft * graft;
+	struct stat st;
+
+	if (stat(source, &st)) {
+		errmsg_die("bad graft source '%s'", source);
+	}
+
+	if(!grafts) grafts = calloc(sizeof (struct graft), 1);
+	for(graft = grafts; graft->next; graft = graft->next)
+		;
+	graft->source = source;
+	graft->dest = dest;
+	memcpy((void *) &(graft->st), (void *) &st, sizeof st);
+	graft->next = calloc(sizeof (struct graft), 1);
+	return 0;
+}
+
 static int load_next_block(void) {
 
 	int ret;
@@ -1579,7 +1620,7 @@ int main(int argc, char **argv)
 	jffs2_compressors_init();
 
 	while ((opt = getopt_long(argc, argv,
-					"D:d:r:s:o:qUPfh?vVe:lbp::nc:m:x:X:Lty:i:", long_options, &c)) >= 0)
+					"D:d:r:G:s:o:qUPfh?vVe:lbp::nc:m:x:X:Lty:i:", long_options, &c)) >= 0)
 	{
 		switch (opt) {
 			case 'D':
@@ -1598,6 +1639,18 @@ int main(int argc, char **argv)
 				rootdir = xstrdup(optarg);
 				break;
 
+			case 'G':
+				if(strchr(optarg, ':')) {
+					char * src_name, * dest_name;
+					src_name = xstrdup(optarg);
+					dest_name = strchr(src_name, ':');
+					*dest_name = '\0';
+					dest_name++;
+					add_graft(src_name, dest_name);
+				} else
+					errmsg_die("bad graft specification '%s', expecting source:dest",
+						   optarg);
+				break;
 			case 's':
 				page_size = strtol(optarg, NULL, 0);
 				warn_page_size = 0; /* set by user, so don't need to warn */
@@ -1784,13 +1837,34 @@ int main(int argc, char **argv)
 		parse_image();
 
 	root = recursive_add_host_directory(NULL, "/", cwd);
+	for(struct graft *g = grafts; g && g->source; g=g->next) {
+		char *tmp = xstrdup(g->dest);
+		struct filesystem_entry * entry =
+			find_filesystem_entry(root, dirname(tmp), S_IFDIR);
+		free(tmp);
+		if(!entry)
+			errmsg_die("missing directory %s for graft point %s",
+				   g->dest, g->source);
 
+		if (S_ISDIR(g->st.st_mode)) {
+			recursive_add_host_directory(entry, g->dest, g->source);
+		} else {
+			add_host_filesystem_entry(g->dest,
+						  g->source,
+						  g->st.st_uid,
+						  g->st.st_gid,
+						  g->st.st_mode,
+						  g->st.st_rdev,
+						  entry);
+		}
+	}
 	if (devtable)
 		parse_device_table(root, devtable);
 
 	create_target_filesystem(root);
 
 	cleanup(root);
+	free_grafts(grafts);
 
 	if (rootdir != default_rootdir)
 		free(rootdir);
-- 
2.38.1