Cleanup: remove most of the payload pointer magic from libfstree

Now that dir_info_t and file_info_t have reasonably small, use them in
tree_node_t directly instead of doing pointer arithmetic magic on the
payload area.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

9 files changed, 41 insertions, 72 deletions

diff --git a/lib/fstree/add_by_path.c b/lib/fstree/add_by_path.c
index 87fa6ff..bd47a76 100644
--- a/lib/fstree/add_by_path.c
+++ b/lib/fstree/add_by_path.c
@@ -14,7 +14,7 @@
 static tree_node_t *child_by_name(tree_node_t *root, const char *name,
 				  size_t len)
 {
-	tree_node_t *n = root->data.dir->children;
+	tree_node_t *n = root->data.dir.children;
 
 	while (n != NULL) {
 		if (strncmp(n->name, name, len) == 0 && n->name[len] == '\0')
@@ -50,7 +50,7 @@ static tree_node_t *get_parent_node(fstree_t *fs, tree_node_t *root,
 			if (n == NULL)
 				return NULL;
 
-			n->data.dir->created_implicitly = true;
+			n->data.dir.created_implicitly = true;
 		}
 
 		root = n;
@@ -76,7 +76,7 @@ tree_node_t *fstree_add_generic(fstree_t *fs, const char *path,
 	child = child_by_name(parent, name, strlen(name));
 	if (child != NULL) {
 		if (!S_ISDIR(child->mode) || !S_ISDIR(sb->st_mode) ||
-		    !child->data.dir->created_implicitly) {
+		    !child->data.dir.created_implicitly) {
 			errno = EEXIST;
 			return NULL;
 		}
@@ -85,7 +85,7 @@ tree_node_t *fstree_add_generic(fstree_t *fs, const char *path,
 		child->gid = sb->st_gid;
 		child->mode = sb->st_mode;
 		child->mod_time = sb->st_mtime;
-		child->data.dir->created_implicitly = false;
+		child->data.dir.created_implicitly = false;
 		return child;
 	}
 
diff --git a/lib/fstree/fstree.c b/lib/fstree/fstree.c
index febf8af..c7c4a23 100644
--- a/lib/fstree/fstree.c
+++ b/lib/fstree/fstree.c
@@ -95,9 +95,9 @@ static void free_recursive(tree_node_t *n)
 	tree_node_t *it;
 
 	if (S_ISDIR(n->mode)) {
-		while (n->data.dir->children != NULL) {
-			it = n->data.dir->children;
-			n->data.dir->children = it->next;
+		while (n->data.dir.children != NULL) {
+			it = n->data.dir.children;
+			n->data.dir.children = it->next;
 
 			free_recursive(it);
 		}
diff --git a/lib/fstree/fstree_from_dir.c b/lib/fstree/fstree_from_dir.c
index 86f7fd8..c31b1a0 100644
--- a/lib/fstree/fstree_from_dir.c
+++ b/lib/fstree/fstree_from_dir.c
@@ -200,7 +200,7 @@ static int populate_dir(fstree_t *fs, tree_node_t *root, dev_t devstart,
 
 	closedir(dir);
 
-	for (n = root->data.dir->children; n != NULL; n = n->next) {
+	for (n = root->data.dir.children; n != NULL; n = n->next) {
 		if (S_ISDIR(n->mode)) {
 			if (pushd(n->name))
 				return -1;
diff --git a/lib/fstree/fstree_sort.c b/lib/fstree/fstree_sort.c
index 53fb58a..9cb177b 100644
--- a/lib/fstree/fstree_sort.c
+++ b/lib/fstree/fstree_sort.c
@@ -63,9 +63,9 @@ tree_node_t *tree_node_list_sort(tree_node_t *head)
 
 void tree_node_sort_recursive(tree_node_t *n)
 {
-	n->data.dir->children = tree_node_list_sort(n->data.dir->children);
+	n->data.dir.children = tree_node_list_sort(n->data.dir.children);
 
-	for (n = n->data.dir->children; n != NULL; n = n->next) {
+	for (n = n->data.dir.children; n != NULL; n = n->next) {
 		if (S_ISDIR(n->mode))
 			tree_node_sort_recursive(n);
 	}
diff --git a/lib/fstree/gen_file_list.c b/lib/fstree/gen_file_list.c
index 6b10b00..f20c131 100644
--- a/lib/fstree/gen_file_list.c
+++ b/lib/fstree/gen_file_list.c
@@ -10,14 +10,14 @@
 static file_info_t *file_list_dfs(tree_node_t *n)
 {
 	if (S_ISREG(n->mode)) {
-		n->data.file->next = NULL;
-		return n->data.file;
+		n->data.file.next = NULL;
+		return &n->data.file;
 	}
 
 	if (S_ISDIR(n->mode)) {
 		file_info_t *list = NULL, *last = NULL;
 
-		for (n = n->data.dir->children; n != NULL; n = n->next) {
+		for (n = n->data.dir.children; n != NULL; n = n->next) {
 			if (list == NULL) {
 				list = file_list_dfs(n);
 				if (list == NULL)
diff --git a/lib/fstree/gen_inode_table.c b/lib/fstree/gen_inode_table.c
index 04f68da..80686d6 100644
--- a/lib/fstree/gen_inode_table.c
+++ b/lib/fstree/gen_inode_table.c
@@ -14,7 +14,7 @@
 
 static size_t count_nodes(tree_node_t *root)
 {
-	tree_node_t *n = root->data.dir->children;
+	tree_node_t *n = root->data.dir.children;
 	size_t count = 1;
 
 	while (n != NULL) {
@@ -34,7 +34,7 @@ static void map_child_nodes(fstree_t *fs, tree_node_t *root, size_t *counter)
 	bool has_subdirs = false;
 	tree_node_t *it;
 
-	for (it = root->data.dir->children; it != NULL; it = it->next) {
+	for (it = root->data.dir.children; it != NULL; it = it->next) {
 		if (S_ISDIR(it->mode)) {
 			has_subdirs = true;
 			break;
@@ -42,13 +42,13 @@ static void map_child_nodes(fstree_t *fs, tree_node_t *root, size_t *counter)
 	}
 
 	if (has_subdirs) {
-		for (it = root->data.dir->children; it != NULL; it = it->next) {
+		for (it = root->data.dir.children; it != NULL; it = it->next) {
 			if (S_ISDIR(it->mode))
 				map_child_nodes(fs, it, counter);
 		}
 	}
 
-	for (it = root->data.dir->children; it != NULL; it = it->next) {
+	for (it = root->data.dir.children; it != NULL; it = it->next) {
 		it->inode_num = *counter;
 		*counter += 1;
 
diff --git a/lib/fstree/mknode.c b/lib/fstree/mknode.c
index 19df268..f90bd00 100644
--- a/lib/fstree/mknode.c
+++ b/lib/fstree/mknode.c
@@ -7,7 +7,6 @@
 #include "config.h"
 
 #include "fstree.h"
-#include "util.h"
 
 #include <string.h>
 #include <stdlib.h>
@@ -17,50 +16,26 @@ tree_node_t *fstree_mknode(tree_node_t *parent, const char *name,
 			   size_t name_len, const char *extra,
 			   const struct stat *sb)
 {
-	size_t size = sizeof(tree_node_t), total;
 	tree_node_t *n;
+	size_t size;
 	char *ptr;
 
-	switch (sb->st_mode & S_IFMT) {
-	case S_IFLNK:
-		if (extra == NULL) {
-			errno = EINVAL;
-			return NULL;
-		}
-		if (SZ_ADD_OV(size, strlen(extra), &size) ||
-		    SZ_ADD_OV(size, 1, &size)) {
-			goto fail_ov;
-		}
-		break;
-	case S_IFDIR:
-		if (SZ_ADD_OV(size, sizeof(*n->data.dir), &size))
-			goto fail_ov;
-		break;
-	case S_IFREG:
-		if (SZ_ADD_OV(size, sizeof(*n->data.file), &size))
-			goto fail_ov;
-
-		if (extra != NULL) {
-			if (SZ_ADD_OV(size, strlen(extra), &size) ||
-			    SZ_ADD_OV(size, 1, &size)) {
-				goto fail_ov;
-			}
-		}
-		break;
+	if (S_ISLNK(sb->st_mode) && extra == NULL) {
+		errno = EINVAL;
+		return NULL;
 	}
 
-	if (SZ_ADD_OV(size, name_len, &total) ||
-	    SZ_ADD_OV(total, 1, &total)) {
-		goto fail_ov;
-	}
+	size = sizeof(tree_node_t) + name_len + 1;
+	if (extra != NULL)
+		size += strlen(extra) + 1;
 
-	n = calloc(1, total);
+	n = calloc(1, size);
 	if (n == NULL)
 		return NULL;
 
 	if (parent != NULL) {
-		n->next = parent->data.dir->children;
-		parent->data.dir->children = n;
+		n->next = parent->data.dir.children;
+		parent->data.dir.children = n;
 		n->parent = parent;
 	}
 
@@ -68,24 +43,23 @@ tree_node_t *fstree_mknode(tree_node_t *parent, const char *name,
 	n->gid = sb->st_gid;
 	n->mode = sb->st_mode;
 	n->mod_time = sb->st_mtime;
+	n->name = (char *)n->payload;
+	memcpy(n->name, name, name_len);
+
+	if (extra != NULL) {
+		ptr = n->name + name_len + 1;
+		strcpy(ptr, extra);
+	} else {
+		ptr = NULL;
+	}
 
 	switch (sb->st_mode & S_IFMT) {
-	case S_IFDIR:
-		n->data.dir = (dir_info_t *)n->payload;
-		break;
 	case S_IFREG:
-		n->data.file = (file_info_t *)n->payload;
-		if (extra != NULL) {
-			ptr = (char *)n->payload + sizeof(file_info_t);
-			n->data.file->input_file = ptr;
-			strcpy(n->data.file->input_file, extra);
-		}
+		n->data.file.input_file = ptr;
 		break;
 	case S_IFLNK:
 		n->mode = S_IFLNK | 0777;
-		n->data.slink_target = (char *)n->payload;
-		if (extra != NULL)
-			strcpy(n->data.slink_target, extra);
+		n->data.slink_target = ptr;
 		break;
 	case S_IFBLK:
 	case S_IFCHR:
@@ -93,10 +67,5 @@ tree_node_t *fstree_mknode(tree_node_t *parent, const char *name,
 		break;
 	}
 
-	n->name = (char *)n + size;
-	memcpy(n->name, name, name_len);
 	return n;
-fail_ov:
-	errno = EOVERFLOW;
-	return NULL;
 }
diff --git a/lib/sqfshelper/serialize_fstree.c b/lib/sqfshelper/serialize_fstree.c
index e012902..296f123 100644
--- a/lib/sqfshelper/serialize_fstree.c
+++ b/lib/sqfshelper/serialize_fstree.c
@@ -26,7 +26,7 @@ static sqfs_inode_generic_t *write_dir_entries(sqfs_dir_writer_t *dirw,
 	if (sqfs_dir_writer_begin(dirw))
 		return NULL;
 
-	for (it = node->data.dir->children; it != NULL; it = it->next) {
+	for (it = node->data.dir.children; it != NULL; it = it->next) {
 		ret = sqfs_dir_writer_add_entry(dirw, it->name, it->inode_num,
 						it->inode_ref, it->mode);
 		if (ret)
diff --git a/lib/sqfshelper/tree_node_to_inode.c b/lib/sqfshelper/tree_node_to_inode.c
index 5cb04a4..edcdee3 100644
--- a/lib/sqfshelper/tree_node_to_inode.c
+++ b/lib/sqfshelper/tree_node_to_inode.c
@@ -52,8 +52,8 @@ sqfs_inode_generic_t *tree_node_to_inode(sqfs_id_table_t *idtbl,
 	size_t extra = 0;
 
 	if (S_ISREG(node->mode)) {
-		inode = node->data.file->user_ptr;
-		node->data.file->user_ptr = NULL;
+		inode = node->data.file.user_ptr;
+		node->data.file.user_ptr = NULL;
 	} else {
 		if (S_ISLNK(node->mode))
 			extra = strlen(node->data.slink_target);