From 563f8dd6f0eb56780a00f5856bf7fcf40e39d845 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@pi.lan>
Date: Fri, 22 Aug 2008 20:11:02 +0200
Subject: [PATCH] code cleanup, some api changes for new uci_ptr struct

---
 cli.c          | 117 ++++++-----------
 file.c         |  30 ++---
 history.c      |   6 +-
 list.c         | 331 ++++++++++++++++++++++++++-----------------------
 uci.h          |  82 +++---------
 uci_internal.h |  15 ++-
 6 files changed, 252 insertions(+), 329 deletions(-)

diff --git a/cli.c b/cli.c
index 16306ff..5a260ef 100644
--- a/cli.c
+++ b/cli.c
@@ -179,53 +179,44 @@ static void uci_show_changes(struct uci_package *p)
 
 static int package_cmd(int cmd, char *tuple)
 {
-	struct uci_package *p;
-	struct uci_section *s;
 	struct uci_element *e = NULL;
+	struct uci_ptr ptr;
 
-	if (uci_lookup_ext(ctx, &e, tuple) != UCI_OK) {
+	if (uci_lookup_ptr(ctx, &ptr, tuple, true) != UCI_OK) {
 		cli_perror();
 		return 1;
 	}
-	switch(e->type) {
-	case UCI_TYPE_PACKAGE:
-		p = uci_to_package(e);
-		break;
-	case UCI_TYPE_SECTION:
-		s = uci_to_section(e);
-		p = s->package;
-		break;
-	case UCI_TYPE_OPTION:
-		s = uci_to_option(e)->section;
-		p = s->package;
-		break;
-	default:
-		return 0;
-	}
+
+	if (ptr.o)
+		e = &ptr.o->e;
+	else if (ptr.s)
+		e = &ptr.s->e;
+	else
+		e = &ptr.p->e;
 
 	switch(cmd) {
 	case CMD_CHANGES:
-		uci_show_changes(p);
+		uci_show_changes(ptr.p);
 		break;
 	case CMD_COMMIT:
 		if (flags & CLI_FLAG_NOCOMMIT)
 			return 0;
-		if (uci_commit(ctx, &p, false) != UCI_OK)
+		if (uci_commit(ctx, &ptr.p, false) != UCI_OK)
 			cli_perror();
 		break;
 	case CMD_EXPORT:
-		uci_export(ctx, stdout, p, true);
+		uci_export(ctx, stdout, ptr.p, true);
 		break;
 	case CMD_SHOW:
 		switch(e->type) {
 			case UCI_TYPE_PACKAGE:
-				uci_show_package(p);
+				uci_show_package(ptr.p);
 				break;
 			case UCI_TYPE_SECTION:
-				uci_show_section(uci_to_section(e));
+				uci_show_section(ptr.s);
 				break;
 			case UCI_TYPE_OPTION:
-				uci_show_option(uci_to_option(e));
+				uci_show_option(ptr.o);
 				break;
 			default:
 				/* should not happen */
@@ -234,7 +225,7 @@ static int package_cmd(int cmd, char *tuple)
 		break;
 	}
 
-	uci_unload(ctx, p);
+	uci_unload(ctx, ptr.p);
 	return 0;
 }
 
@@ -335,74 +326,36 @@ done:
 
 static int uci_do_section_cmd(int cmd, int argc, char **argv)
 {
-	struct uci_package *p = NULL;
-	struct uci_section *s = NULL;
-	struct uci_element *e = NULL;
-	struct uci_option *o = NULL;
-	char *section = NULL;
-	char *option = NULL;
-	char *value = NULL;
+	struct uci_element *e;
+	struct uci_ptr ptr;
 	int ret = UCI_OK;
-	char *str;
 
 	if (argc != 2)
 		return 255;
 
-	value = strchr(argv[1], '=');
-	if (value) {
-		*value = 0;
-		value++;
-		if (!uci_validate_text(value))
-			return 1;
-	}
-
-	if (value && (cmd != CMD_SET) && (cmd != CMD_ADD_LIST) && (cmd != CMD_RENAME))
-		return 1;
-
-	do {
-		str = strchr(argv[1], '.'); /* look up section part */
-		if (!str)
-			break;
-
-		str++;
-		str = strchr(str, '.'); /* look up option part */
-		if (!str)
-			break;
-
-		/* separate option from the rest of the pointer */
-		*str = 0;
-		option = str + 1;
-	} while (0);
-
-	if (uci_lookup_ext(ctx, &e, argv[1]) != UCI_OK) {
+	if (uci_lookup_ptr(ctx, &ptr, argv[1], true) != UCI_OK) {
 		cli_perror();
 		return 1;
 	}
 
-	switch(e->type) {
-	case UCI_TYPE_PACKAGE:
-		p = uci_to_package(e);
-		break;
-	case UCI_TYPE_SECTION:
-		s = uci_to_section(e);
-		break;
-	default:
+	if (ptr.value && (cmd != CMD_SET) && (cmd != CMD_ADD_LIST) && (cmd != CMD_RENAME))
 		return 1;
-	}
-	if (s) {
-		section = s->e.name;
-		p = s->package;
-	}
+
+	if (ptr.o)
+		e = &ptr.o->e;
+	else if (ptr.s)
+		e = &ptr.s->e;
+	else
+		e = &ptr.p->e;
 
 	switch(cmd) {
 	case CMD_GET:
 		switch(e->type) {
 		case UCI_TYPE_SECTION:
-			printf("%s\n", s->type);
+			printf("%s\n", ptr.s->type);
 			break;
 		case UCI_TYPE_OPTION:
-			o = uci_to_option(e);
-			uci_show_value(o);
+			uci_show_value(ptr.o);
 			break;
 		default:
 			break;
@@ -410,19 +363,19 @@ static int uci_do_section_cmd(int cmd, int argc, char **argv)
 		/* throw the value to stdout */
 		break;
 	case CMD_RENAME:
-		ret = uci_rename(ctx, p, section, option, value);
+		ret = uci_rename(ctx, &ptr);
 		break;
 	case CMD_REVERT:
-		ret = uci_revert(ctx, &p, section, option);
+		ret = uci_revert(ctx, &ptr.p, ptr.section, ptr.option);
 		break;
 	case CMD_SET:
-		ret = uci_set(ctx, p, section, option, value, NULL);
+		ret = uci_set(ctx, ptr.p, ptr.section, ptr.option, ptr.value, NULL);
 		break;
 	case CMD_ADD_LIST:
-		ret = uci_add_list(ctx, p, section, option, value, NULL);
+		ret = uci_add_list(ctx, &ptr);
 		break;
 	case CMD_DEL:
-		ret = uci_delete(ctx, p, section, option);
+		ret = uci_delete(ctx, &ptr);
 		break;
 	}
 
@@ -432,7 +385,7 @@ static int uci_do_section_cmd(int cmd, int argc, char **argv)
 
 	/* save changes, but don't commit them yet */
 	if (ret == UCI_OK)
-		ret = uci_save(ctx, p);
+		ret = uci_save(ctx, ptr.p);
 
 	if (ret != UCI_OK) {
 		cli_perror();
diff --git a/file.c b/file.c
index d551208..c670f04 100644
--- a/file.c
+++ b/file.c
@@ -167,6 +167,7 @@ error:
 static void uci_parse_list(struct uci_context *ctx, char **str)
 {
 	struct uci_parse_context *pctx = ctx->pctx;
+	struct uci_ptr ptr;
 	char *name = NULL;
 	char *value = NULL;
 
@@ -180,27 +181,14 @@ static void uci_parse_list(struct uci_context *ctx, char **str)
 	value = next_arg(ctx, str, false, false);
 	assert_eol(ctx, str);
 
-	if (pctx->merge) {
-		UCI_TRAP_SAVE(ctx, error);
-		uci_add_list(ctx, pctx->package, pctx->section->e.name, name, value, NULL);
-		UCI_TRAP_RESTORE(ctx);
-		return;
-error:
-		UCI_THROW(ctx, ctx->err);
-	} else {
-		struct uci_option *o;
-		struct uci_element *e;
-
-		e = uci_lookup_list(&pctx->section->options, name);
-		o = uci_to_option(e);
-		if (!o) {
-			o = uci_alloc_list(pctx->section, name);
-		} else {
-			if (o->type != UCI_TYPE_LIST)
-				uci_parse_error(ctx, *str, "conflicting list/option keywords");
-		}
-		UCI_INTERNAL(uci_add_element_list, ctx, o, value);
-	}
+	UCI_NESTED(uci_fill_ptr, ctx, &ptr, &pctx->section->e, false);
+	ptr.option = name;
+	ptr.value = value;
+
+	UCI_INTERNAL(uci_lookup_ptr, ctx, &ptr, NULL, false);
+
+	ctx->internal = !pctx->merge;
+	UCI_NESTED(uci_add_list, ctx, &ptr);
 }
 
 
diff --git a/history.c b/history.c
index 4e97524..07db1d3 100644
--- a/history.c
+++ b/history.c
@@ -150,13 +150,13 @@ static void uci_parse_history_line(struct uci_context *ctx, struct uci_package *
 
 	switch(cmd) {
 	case UCI_CMD_RENAME:
-		UCI_INTERNAL(uci_rename, ctx, p, ptr.section, ptr.option, ptr.value);
+		UCI_INTERNAL(uci_rename, ctx, &ptr);
 		break;
 	case UCI_CMD_REMOVE:
-		UCI_INTERNAL(uci_delete, ctx, p, ptr.section, ptr.option);
+		UCI_INTERNAL(uci_delete, ctx, &ptr);
 		break;
 	case UCI_CMD_LIST_ADD:
-		UCI_INTERNAL(uci_add_list, ctx, p, ptr.section, ptr.option, ptr.value, NULL);
+		UCI_INTERNAL(uci_add_list, ctx, &ptr);
 		break;
 	case UCI_CMD_ADD:
 	case UCI_CMD_CHANGE:
diff --git a/list.c b/list.c
index d7b9f69..e770234 100644
--- a/list.c
+++ b/list.c
@@ -253,6 +253,22 @@ uci_free_package(struct uci_package **package)
 	*package = NULL;
 }
 
+static void
+uci_free_any(struct uci_element **e)
+{
+	switch((*e)->type) {
+	case UCI_TYPE_SECTION:
+		uci_free_section(uci_to_section(*e));
+		break;
+	case UCI_TYPE_OPTION:
+		uci_free_option(uci_to_option(*e));
+		break;
+	default:
+		break;
+	}
+	*e = NULL;
+}
+
 static struct uci_element *uci_lookup_list(struct uci_list *list, const char *name)
 {
 	struct uci_element *e;
@@ -264,51 +280,21 @@ static struct uci_element *uci_lookup_list(struct uci_list *list, const char *na
 	return NULL;
 }
 
-int uci_lookup_ext(struct uci_context *ctx, struct uci_element **res, char *str)
+static struct uci_element *uci_lookup_ext_section(struct uci_context *ctx, struct uci_ptr *ptr)
 {
-	struct uci_package *p = NULL;
-	struct uci_element *e;
+	char *idxstr, *t, *section, *name;
+	struct uci_element *e = NULL;
 	struct uci_section *s;
-	struct uci_ptr ptr;
-	char *idxstr, *t;
 	int idx, c;
 
-	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, res != NULL);
-	UCI_ASSERT(ctx, str != NULL);
-
-	UCI_INTERNAL(uci_parse_ptr, ctx, &ptr, str);
+	section = uci_strdup(ctx, ptr->section);
+	name = idxstr = section + 1;
 
-	/* look up the package first */
-	e = uci_lookup_list(&ctx->root, ptr.package);
-	if (!e) {
-		UCI_INTERNAL(uci_load, ctx, ptr.package, &p);
-		if (!p)
-			goto notfound;
-		e = &p->e;
-	} else {
-		p = uci_to_package(e);
-	}
-
-	if (!ptr.section)
-		goto done;
-
-	/* if the section name validates as a regular name, pass through
-	 * to the regular uci_lookup function call */
-	if (!(ptr.flags & UCI_LOOKUP_EXTENDED)) {
-		UCI_INTERNAL(uci_lookup, ctx, &e, p, ptr.section, ptr.option);
-		goto done;
-	}
-
-	/* name did not validate, that means we have an extended lookup call
-	 * parse it here. for now only the section index syntax is supported */
-	if (ptr.section[0] != '@')
+	if (section[0] != '@')
 		goto error;
 
-	ptr.section++;
-
 	/* parse the section index part */
-	idxstr = strchr(ptr.section, '[');
+	idxstr = strchr(idxstr, '[');
 	if (!idxstr)
 		goto error;
 	*idxstr = 0;
@@ -326,18 +312,18 @@ int uci_lookup_ext(struct uci_context *ctx, struct uci_element **res, char *str)
 	if (t && *t)
 		goto error;
 
-	if (!*ptr.section)
-		ptr.section = NULL;
-	if (ptr.section && !uci_validate_str(ptr.section, false))
+	if (!*name)
+		name = NULL;
+	else if (!uci_validate_str(name, false))
 		goto error;
 
 	/* if the given index is negative, it specifies the section number from 
 	 * the end of the list */
 	if (idx < 0) {
 		c = 0;
-		uci_foreach_element(&p->sections, e) {
+		uci_foreach_element(&ptr->p->sections, e) {
 			s = uci_to_section(e);
-			if (ptr.section && (strcmp(s->type, ptr.section) != 0))
+			if (name && (strcmp(s->type, name) != 0))
 				continue;
 
 			c++;
@@ -346,55 +332,75 @@ int uci_lookup_ext(struct uci_context *ctx, struct uci_element **res, char *str)
 	}
 
 	c = 0;
-	uci_foreach_element(&p->sections, e) {
+	uci_foreach_element(&ptr->p->sections, e) {
 		s = uci_to_section(e);
-		if (ptr.section && (strcmp(s->type, ptr.section) != 0))
+		if (name && (strcmp(s->type, name) != 0))
 			continue;
 
 		if (idx == c)
-			goto found;
+			goto done;
 		c++;
 	}
-	goto notfound;
-
-found:
-	if (ptr.option)
-		e = uci_lookup_list(&s->options, ptr.option);
-done:
-	*res = e;
-	return 0;
+	e = NULL;
+	goto done;
 
-notfound:
-	UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 error:
+	e = NULL;
+	memset(ptr, 0, sizeof(struct uci_ptr));
 	UCI_THROW(ctx, UCI_ERR_INVAL);
-	return 0;
+done:
+	free(section);
+	return e;
 }
 
-int uci_lookup(struct uci_context *ctx, struct uci_element **res, struct uci_package *p, const char *section, const char *option)
+int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended)
 {
 	struct uci_element *e;
-	struct uci_section *s;
 
 	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, res != NULL);
-	UCI_ASSERT(ctx, p != NULL);
-	UCI_ASSERT(ctx, section && uci_validate_name(section));
-	if (option)
-		UCI_ASSERT(ctx, uci_validate_name(option));
+	UCI_ASSERT(ctx, ptr != NULL);
+
+	if (str)
+		UCI_INTERNAL(uci_parse_ptr, ctx, ptr, str);
+
+	ptr->flags |= UCI_LOOKUP_DONE;
+
+	/* look up the package first */
+	e = uci_lookup_list(&ctx->root, ptr->package);
+	if (!e) {
+		UCI_INTERNAL(uci_load, ctx, ptr->package, &ptr->p);
+		if (!ptr->p)
+			goto notfound;
+	} else {
+		ptr->p = uci_to_package(e);
+	}
+
+	if (!ptr->section)
+		goto complete;
+
+	/* if the section name validates as a regular name, pass through
+	 * to the regular uci_lookup function call */
+	if (ptr->flags & UCI_LOOKUP_EXTENDED)
+		e = uci_lookup_ext_section(ctx, ptr);
+	else
+		e = uci_lookup_list(&ptr->p->sections, ptr->section);
 
-	e = uci_lookup_list(&p->sections, section);
 	if (!e)
-		goto notfound;
+		goto abort;
 
-	if (option) {
-		s = uci_to_section(e);
-		e = uci_lookup_list(&s->options, option);
+	ptr->s = uci_to_section(e);
+
+	if (ptr->option) {
+		e = uci_lookup_list(&ptr->s->options, ptr->option);
 		if (!e)
-			goto notfound;
+			goto abort;
+
+		ptr->o = uci_to_option(e);
 	}
 
-	*res = e;
+complete:
+	ptr->flags |= UCI_LOOKUP_COMPLETE;
+abort:
 	return 0;
 
 notfound:
@@ -402,75 +408,84 @@ notfound:
 	return 0;
 }
 
-int uci_del_element(struct uci_context *ctx, struct uci_element *e)
+int
+uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e, bool complete)
 {
-	/* NB: UCI_INTERNAL use means without history tracking */
-	bool internal = ctx->internal;
-	struct uci_package *p = NULL;
-	struct uci_section *s = NULL;
-	struct uci_option *o = NULL;
-	struct uci_element *i, *tmp;
-	char *option = NULL;
-
 	UCI_HANDLE_ERR(ctx);
+	UCI_ASSERT(ctx, ptr != NULL);
 	UCI_ASSERT(ctx, e != NULL);
 
+	memset(ptr, 0, sizeof(struct uci_ptr));
 	switch(e->type) {
-	case UCI_TYPE_SECTION:
-		s = uci_to_section(e);
-		uci_foreach_element_safe(&s->options, tmp, i) {
-			uci_del_element(ctx, i);
-		}
-		break;
 	case UCI_TYPE_OPTION:
-		o = uci_to_option(e);
-		s = o->section;
-		p = s->package;
-		option = e->name;
-		break;
+		ptr->o = uci_to_option(e);
+		goto fill_option;
+	case UCI_TYPE_SECTION:
+		ptr->s = uci_to_section(e);
+		goto fill_section;
+	case UCI_TYPE_PACKAGE:
+		ptr->p = uci_to_package(e);
+		goto fill_package;
 	default:
 		UCI_THROW(ctx, UCI_ERR_INVAL);
-		break;
 	}
 
-	p = s->package;
-	if (!internal && p->has_history)
-		uci_add_history(ctx, &p->history, UCI_CMD_REMOVE, s->e.name, option, NULL);
+fill_option:
+	ptr->option = ptr->o->e.name;
+	ptr->s = ptr->o->section;
+fill_section:
+	ptr->section = ptr->s->e.name;
+	ptr->p = ptr->s->package;
+fill_package:
+	ptr->package = ptr->p->e.name;
 
-	switch(e->type) {
-	case UCI_TYPE_SECTION:
-		uci_free_section(s);
-		break;
-	case UCI_TYPE_OPTION:
-		uci_free_option(o);
-		break;
-	default:
-		break;
-	}
+	ptr->flags |= UCI_LOOKUP_DONE;
+	if (complete)
+		ptr->flags |= UCI_LOOKUP_COMPLETE;
 
 	return 0;
 }
 
-int uci_add_element_list(struct uci_context *ctx, struct uci_option *o, const char *value)
+static struct uci_element *
+expand_ptr(struct uci_context *ctx, struct uci_ptr *ptr, bool complete)
 {
-	struct uci_element *e;
-	struct uci_package *p;
-	struct uci_section *s;
-	bool internal = ctx->internal;
+	UCI_ASSERT(ctx, ptr != NULL);
 
-	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, (o != NULL) && (o->type == UCI_TYPE_LIST) && uci_validate_text(value));
+	if (!(ptr->flags & UCI_LOOKUP_DONE))
+		uci_lookup_ptr(ctx, ptr, NULL, 1);
+	if (complete && !(ptr->flags & UCI_LOOKUP_COMPLETE))
+		UCI_THROW(ctx, UCI_ERR_NOTFOUND);
+	UCI_ASSERT(ctx, ptr->p != NULL);
+
+	/* fill in missing string info */
+	if (ptr->p && !ptr->package)
+		ptr->package = ptr->p->e.name;
+	if (ptr->s && !ptr->section)
+		ptr->section = ptr->s->e.name;
+	if (ptr->o && !ptr->option)
+		ptr->option = ptr->o->e.name;
+
+	if (ptr->o)
+		return &ptr->o->e;
+	if (ptr->s)
+		return &ptr->s->e;
+	if (ptr->p)
+		return &ptr->p->e;
+	else
+		return NULL;
+}
 
-	s = o->section;
-	p = s->package;
+static void uci_add_element_list(struct uci_context *ctx, struct uci_ptr *ptr, bool internal)
+{
+	struct uci_element *e;
+	struct uci_package *p;
 
+	p = ptr->p;
 	if (!internal && p->has_history)
-		uci_add_history(ctx, &p->history, UCI_CMD_LIST_ADD, s->e.name, o->e.name, value);
+		uci_add_history(ctx, &p->history, UCI_CMD_LIST_ADD, ptr->section, ptr->option, ptr->value);
 
-	e = uci_alloc_generic(ctx, UCI_TYPE_ITEM, value, sizeof(struct uci_option));
-	uci_list_add(&o->v.list, &e->list);
-
-	return 0;
+	e = uci_alloc_generic(ctx, UCI_TYPE_ITEM, ptr->value, sizeof(struct uci_option));
+	uci_list_add(&ptr->o->v.list, &e->list);
 }
 
 int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, const char *value)
@@ -544,7 +559,7 @@ int uci_set_element_value(struct uci_context *ctx, struct uci_element **element,
 
 	if ((e->type == UCI_TYPE_OPTION) && (size == 0)) {
 		o = uci_alloc_option(s, option, value);
-		UCI_INTERNAL(uci_del_element, ctx, e);
+		uci_free_any(&e);
 		*element = &o->e;
 		goto done;
 	}
@@ -570,24 +585,29 @@ done:
 	return 0;
 }
 
-int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name)
+int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: UCI_INTERNAL use means without history tracking */
 	bool internal = ctx->internal;
 	struct uci_element *e;
+	struct uci_package *p;
+	char *n;
 
 	UCI_HANDLE_ERR(ctx);
 
-	/* NB: p, section, option validated by uci_lookup */
-	UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
+	e = expand_ptr(ctx, ptr, true);
+	p = ptr->p;
+
+	UCI_ASSERT(ctx, ptr->s);
+	UCI_ASSERT(ctx, ptr->value);
 
 	if (!internal && p->has_history)
-		uci_add_history(ctx, &p->history, UCI_CMD_RENAME, section, option, name);
+		uci_add_history(ctx, &p->history, UCI_CMD_RENAME, ptr->section, ptr->option, ptr->value);
 
-	name = uci_strdup(ctx, name);
+	n = uci_strdup(ctx, ptr->value);
 	if (e->name)
 		free(e->name);
-	e->name = name;
+	e->name = n;
 
 	return 0;
 }
@@ -608,71 +628,66 @@ int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *
 	return 0;
 }
 
-int uci_delete(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option)
+int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: pass on internal flag to uci_del_element */
 	bool internal = ctx->internal;
+	struct uci_package *p;
 	struct uci_element *e;
 
 	UCI_HANDLE_ERR(ctx);
 
-	/* NB: p, section, option validated by uci_lookup */
-	UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
+	e = expand_ptr(ctx, ptr, true);
+	p = ptr->p;
 
-	ctx->internal = internal;
-	return uci_del_element(ctx, e);
+	UCI_ASSERT(ctx, ptr->s);
+
+	if (!internal && p->has_history)
+		uci_add_history(ctx, &p->history, UCI_CMD_REMOVE, ptr->section, ptr->option, NULL);
+
+	uci_free_any(&e);
+	return 0;
 }
 
-int uci_add_list(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_option **result)
+int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: UCI_INTERNAL use means without history tracking */
 	bool internal = ctx->internal;
-	struct uci_element *e;
-	struct uci_section *s;
-	struct uci_option *o;
 	struct uci_option *prev = NULL;
 	const char *value2 = NULL;
 
 	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, p && section && option && value && uci_validate_text(value));
 
-	/* look up the section first */
-	UCI_INTERNAL(uci_lookup, ctx, &e, p, section, NULL);
-	s = uci_to_section(e);
+	expand_ptr(ctx, ptr, false);
+	UCI_ASSERT(ctx, ptr->s);
+	UCI_ASSERT(ctx, ptr->value);
 
-	e = uci_lookup_list(&s->options, option);
-	if (e) {
-		o = uci_to_option(e);
-		switch (o->type) {
+	if (ptr->o) {
+		switch (ptr->o->type) {
 		case UCI_TYPE_STRING:
-			/* we already have a string value, let's convert that to a list */
-			prev = o;
-			value2 = value;
-			value = o->v.string;
+			/* we already have a string value, convert that to a list */
+			prev = ptr->o;
+			value2 = ptr->value;
+			ptr->value = ptr->o->v.string;
 			break;
 		case UCI_TYPE_LIST:
-			if (result)
-				*result = o;
-
-			ctx->internal = internal;
-			return uci_add_element_list(ctx, o, value);
+			uci_add_element_list(ctx, ptr, internal);
+			return 0;
 		default:
 			UCI_THROW(ctx, UCI_ERR_INVAL);
 			break;
 		}
 	}
 
-	o = uci_alloc_list(s, option);
-	if (result)
-		*result = o;
+	ptr->o = uci_alloc_list(ptr->s, ptr->option);
 	if (prev) {
-		UCI_INTERNAL(uci_add_element_list, ctx, o, value);
+		uci_add_element_list(ctx, ptr, true);
 		uci_free_option(prev);
-		value = value2;
+		ptr->value = value2;
 	}
+	uci_add_element_list(ctx, ptr, internal);
 
-	ctx->internal = internal;
-	return uci_add_element_list(ctx, o, value);
+	return 0;
 }
 
 int uci_set(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_element **result)
diff --git a/uci.h b/uci.h
index fe05bb3..ed1a834 100644
--- a/uci.h
+++ b/uci.h
@@ -123,44 +123,21 @@ extern int uci_load(struct uci_context *ctx, const char *name, struct uci_packag
 extern int uci_unload(struct uci_context *ctx, struct uci_package *p);
 
 /**
- * uci_lookup: Look up an uci element
- *
- * @ctx: uci context
- * @res: where to store the result
- * @package: uci_package struct 
- * @section: config section (optional)
- * @option: option to search for (optional)
- *
- * If section is omitted, then a pointer to the config package is returned
- * If option is omitted, then a pointer to the config section is returned
- */
-extern int uci_lookup(struct uci_context *ctx, struct uci_element **res, struct uci_package *package, const char *section, const char *option);
-
-/**
- * uci_lookup_ptr: Split an uci tuple string and look up elements
+ * uci_lookup_ptr: Split an uci tuple string and look up an element tree
  * @ctx: uci context
  * @ptr: lookup result struct
  * @str: uci tuple string to look up
  * @extended: allow extended syntax lookup
- */
-extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
-
-/**
- * uci_lookup_ext: Extended lookup for an uci element
- *
- * @ctx: uci context
- * @res: where to store the result
- * @ptr: uci pointer tuple
  *
- * Looks up an element using the extended syntax.
- * It can look up sections by an index with an optional type.
+ * if extended is set to true, uci_lookup_ptr supports the following 
+ * extended syntax:
  *
  * Examples:
  *   network.@interface[0].ifname ('ifname' option of the first interface section)
  *   network.@interface[-1]       (last interface section)
  * Note: uci_lookup_ext will automatically load a config package if necessary
  */
-extern int uci_lookup_ext(struct uci_context *ctx, struct uci_element **res, char *ptr);
+extern int uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended);
 
 /**
  * uci_add_section: Add an unnamed section
@@ -182,14 +159,6 @@ extern int uci_add_section(struct uci_context *ctx, struct uci_package *p, const
  */
 extern int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, const char *value);
 
-/**
- * uci_add_element_list: Append a string to a list option
- * @ctx: uci context
- * @option: pointer to the uci option element
- * @value: string to append
- */
-extern int uci_add_element_list(struct uci_context *ctx, struct uci_option *o, const char *value);
-
 /**
  * uci_set: Set an element's value; create the element if necessary
  * @ctx: uci context
@@ -204,42 +173,26 @@ extern int uci_set(struct uci_context *ctx, struct uci_package *p, const char *s
 /**
  * uci_add_list: Append a string to an element list
  * @ctx: uci context
- * @package: package name
- * @section: section name
- * @option: option name
- * @value: string value
- * @result: store the updated element in this variable (optional)
+ * @ptr: uci pointer (with value)
  *
- * Note: if the given option already contains a string, convert it to an 1-element-list
- * before appending the next element
+ * Note: if the given option already contains a string value,
+ * it will be converted to an 1-element-list before appending the next element
  */
-extern int uci_add_list(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_option **result);
+extern int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr);
 
 /**
  * uci_rename: Rename an element
  * @ctx: uci context
- * @package: package name
- * @section: section name
- * @option: option name
- * @name: new name
+ * @ptr: uci pointer (with value)
  */
-extern int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name);
-
-/**
- * uci_delete_element: Delete a section or option
- * @ctx: uci context
- * @e: element (section or option)
- */
-extern int uci_delete_element(struct uci_context *ctx, struct uci_element *e);
+extern int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr);
 
 /**
  * uci_delete: Delete a section or option
  * @ctx: uci context
- * @p: uci package
- * @section: section name
- * @option: option name (optional)
+ * @ptr: uci pointer 
  */
-extern int uci_delete(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option);
+extern int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr);
 
 /**
  * uci_save: save change history for a package
@@ -395,7 +348,7 @@ struct uci_context
 	int err;
 	const char *func;
 	jmp_buf trap;
-	bool internal;
+	bool internal, nested;
 	char *buf;
 	int bufsz;
 };
@@ -464,11 +417,12 @@ struct uci_ptr
 	struct uci_package *p;
 	struct uci_section *s;
 	struct uci_option *o;
+	struct uci_element *last;
 
-	char *package;
-	char *section;
-	char *option;
-	char *value;
+	const char *package;
+	const char *section;
+	const char *option;
+	const char *value;
 };
 
 
diff --git a/uci_internal.h b/uci_internal.h
index eba0143..111982e 100644
--- a/uci_internal.h
+++ b/uci_internal.h
@@ -114,9 +114,10 @@ struct uci_backend _var = {		\
 	ctx->err = 0;			\
 	if (!ctx)			\
 		return UCI_ERR_INVAL;	\
-	if (!ctx->internal)		\
+	if (!ctx->internal && !ctx->nested) \
 		__val = setjmp(ctx->trap); \
 	ctx->internal = false;		\
+	ctx->nested = false;		\
 	if (__val) {			\
 		DPRINTF("LEAVE: %s, ret=%d\n", __func__, __val); \
 		ctx->err = __val;	\
@@ -155,6 +156,18 @@ struct uci_backend _var = {		\
 	func(ctx, __VA_ARGS__);		\
 } while (0)
 
+/**
+ * UCI_NESTED: Do an normal nested call of a public API function
+ * 
+ * Sets Exception handling to passthrough mode.
+ * Allows API functions to change behavior compared to public use
+ */
+#define UCI_NESTED(func, ctx, ...) do { \
+	ctx->nested = true;		\
+	func(ctx, __VA_ARGS__);		\
+} while (0)
+
+
 /*
  * check the specified condition.
  * throw an invalid argument exception if it's false
-- 
2.30.2