l0dable: depend on alloc as follow-up to str_to_cstr removal

Cargo.lock

@@ -98,6 +98,7 @@ dependencies = [
 name = "card10-l0dable"
 version = "0.3.0"
 dependencies = [
+ "card10-alloc 0.1.1",
  "card10-sys 1.10.0",
  "embedded-graphics 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]

card10-l0dable/Cargo.toml

@@ -29,4 +29,5 @@ documentation = "https://docs.rs/card10-l0dable"
 
 [dependencies]
 card10-sys = { path = "../card10-sys" }
+card10-alloc = { path = "../card10-alloc" }
 embedded-graphics = "0.5"

card10-l0dable/src/fs.rs

@@ -2,6 +2,7 @@
 
 use core::mem::uninitialized;
 use core::str::from_utf8_unchecked;
+use alloc::format;
 
 use card10_sys::*;
 
@@ -30,7 +31,7 @@ impl From<i32> for Error {
 }
 
 pub fn read_dir(path: &str) -> Result<ReadDir> {
-    let pathbuf = crate::str_to_cstr(path);
+    let pathbuf = format!("{}\0", path);
     Error::check(|| unsafe { epic_file_opendir(pathbuf.as_ptr()) }).map(|fd| ReadDir { fd })
 }
 
@@ -104,8 +105,8 @@ impl DirStat {
 }
 
 pub fn rename(from: &str, to: &str) -> Result<()> {
-    let frombuf = crate::str_to_cstr(from);
-    let tobuf = crate::str_to_cstr(to);
+    let frombuf = format!("{}\0", from);
+    let tobuf = format!("{}\0", to);
     Error::check(|| unsafe { epic_file_rename(frombuf.as_ptr(), tobuf.as_ptr()) }).map(|_| ())
 }
 
@@ -115,7 +116,7 @@ pub struct File {
 
 impl File {
     pub fn open(path: &str) -> Result<File> {
-        let pathbuf = crate::str_to_cstr(path);
+        let pathbuf = format!("{}\0", path);
         let modebuf = b"r\0";
         Error::check(|| unsafe { epic_file_open(pathbuf.as_ptr(), modebuf.as_ptr()) })
             .map(|fd| File { fd })

card10-l0dable/src/lib.rs

 //! [Repository](https://git.card10.badge.events.ccc.de/astro/rust-card10)
 #![no_std]
 
+use card10_alloc as _;
+extern crate alloc;
+
 mod os;
 pub use os::*;
 mod display;

card10-l0dable/src/os.rs

+use alloc::format;
 use card10_sys::*;
 
 /// Execute Python script or ELF file
 pub fn exec(path: &str) -> ! {
-    let mut pathbuf = super::str_to_cstr(path);
+    let mut pathbuf = format!("{}\0", path);
     unsafe {
         epic_exec(pathbuf.as_mut_ptr());
     }