ucode: backport uci.foreach fix

Signed-off-by: John Crispin <john@phrozen.org>

feeds/ucentral/ucode/patches/0009-uci_foreach.patch

@@ -0,0 +1,58 @@
+From d2cc00310dba05de233ff18d3c830c8638f9bfdf Mon Sep 17 00:00:00 2001
+From: Jo-Philipp Wich <jo@mein.io>
+Date: Wed, 23 Nov 2022 12:48:07 +0100
+Subject: [PATCH] uci: auto-load package in `ctx.foreach()` and
+ `ctx.get_first()`
+
+Functions that use `uci_lookup_ptr()` internally, such as `ctx.get()`,
+`ctx.set()` or `ctx.delete()`, implicitly load the given configuration
+name while the higher level functions `ctx.foreach()` or `ctx.get_first()`
+do not.
+
+This behaviour violates the principle of least surprise and might lead to
+non-deterministic program behavior as the outcome of these functions
+depends on prior uci operations performed on the cursor.
+
+Fix this issue by invoking `uci_load()` internally in case the given
+uci package name cannot be found in the cursor's package cache.
+
+Signed-off-by: Jo-Philipp Wich <jo@mein.io>
+---
+ lib/uci.c | 10 ++++------
+ 1 file changed, 4 insertions(+), 6 deletions(-)
+
+diff --git a/lib/uci.c b/lib/uci.c
+index 50cc050e..b88dabd1 100644
+--- a/lib/uci.c
++++ b/lib/uci.c
+@@ -346,8 +346,8 @@ uc_uci_get_first(uc_vm_t *vm, size_t nargs)
+ 		break;
+ 	}
+ 
+-	if (!p)
+-		err_return(UCI_ERR_NOTFOUND);
++	if (!p && uci_load(*c, ucv_string_get(conf), &p))
++		err_return((*c)->err);
+ 
+ 	uci_foreach_element(&p->sections, e) {
+ 		sc = uci_to_section(e);
+@@ -917,8 +917,8 @@ uc_uci_foreach(uc_vm_t *vm, size_t nargs)
+ 		break;
+ 	}
+ 
+-	if (!p)
+-		err_return(UCI_ERR_NOTFOUND);
++	if (!p && uci_load(*c, ucv_string_get(conf), &p))
++		err_return((*c)->err);
+ 
+ 	uci_foreach_element_safe(&p->sections, tmp, e) {
+ 		sc = uci_to_section(e);
+@@ -946,8 +946,6 @@ uc_uci_foreach(uc_vm_t *vm, size_t nargs)
+ 			break;
+ 	}
+ 
+-	/* XXX: rethrow */
+-
+ 	return ucv_boolean_new(ret);
+ }
+