Specify wire version in source, instead of getting it from cargo/git.

Cargo.toml

@@ -58,9 +58,6 @@ lto = "fat"
 opt-level = 3
 overflow-checks = false
 
-[build-dependencies]
-semver = "1.0"
-
 [package.metadata.docs.rs]
 features = ["alloc"]
 rustdoc-args = [ "--cfg=docsrs" ]

build.rs

@@ -1,40 +1,9 @@
-use semver::Version;
-use std::{env, error::Error, fs, path::Path, path::PathBuf, process::Command};
+use std::{env, error::Error, fs, path::PathBuf};
 
 fn main() -> Result<(), Box<dyn Error>> {
     // Put the linker script somewhere the linker can find it
     let out = &PathBuf::from(env::var("OUT_DIR")?);
-    let mut linker_script = fs::read_to_string("defmt.x.in")?;
-    let hash = Command::new("git")
-        .args(&["rev-parse", "HEAD"])
-        .output()
-        .ok()
-        .and_then(|output| {
-            if output.status.success() {
-                String::from_utf8(output.stdout).ok()
-            } else {
-                None
-            }
-        });
-    let version = if let Some(hash) = hash {
-        hash
-    } else {
-        assert!(
-            !Path::new(".git").exists(),
-            "you need to install the `git` command line tool to use the git version of `defmt`"
-        );
-
-        // no git info -> assume crates.io
-        let semver = Version::parse(&std::env::var("CARGO_PKG_VERSION")?)?;
-        if semver.major == 0 {
-            // minor is breaking when major = 0
-            format!("{}.{}", semver.major, semver.minor)
-        } else {
-            // ignore minor, patch, pre and build
-            semver.major.to_string()
-        }
-    };
-    linker_script = linker_script.replace("$DEFMT_VERSION", version.trim());
+    let linker_script = fs::read_to_string("defmt.x.in")?;
     fs::write(out.join("defmt.x"), linker_script)?;
     println!("cargo:rustc-link-search={}", out.display());
     let target = env::var("TARGET")?;

decoder/Cargo.toml

@@ -28,9 +28,6 @@ object = { version = "0.25", default-features = false, features = ["read_core",
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 
-[build-dependencies]
-semver = "1.0"
-
 [features]
 # WARNING: API and wire format subject to change.
 unstable = []

decoder/src/elf2table/mod.rs

@@ -201,52 +201,12 @@ pub fn parse_impl(elf: &[u8], check_version: bool) -> Result<Option<Table>, anyh
 
 /// Checks if the version encoded in the symbol table is compatible with this version of the `decoder` crate
 fn check_version(version: &str) -> Result<(), String> {
-    enum Kind {
-        /// `1` or `0.1`
-        Semver,
-        /// commit hash `e739d0ac703dfa629a159be329e8c62a1c3ed206`
-        Git,
-    }
-
-    impl Kind {
-        fn of(version: &str) -> Kind {
-            if version.contains('.') || version.parse::<u64>().is_ok() {
-                Kind::Semver
-            } else {
-                Kind::Git
-            }
-        }
-    }
-
     if version != DEFMT_VERSION {
-        let mut msg = format!(
-            "defmt version mismatch: firmware is using {}, `probe-run` supports {}\nsuggestion: ",
-            version, DEFMT_VERSION
+        let msg = format!(
+            "defmt wire format version mismatch: firmware is using {}, `probe-run` supports {}\nsuggestion: `cargo install` a different version of `probe-run` that supports defmt {}",
+            version, DEFMT_VERSION, DEFMT_VERSION
         );
 
-        let git_sem = "migrate your firmware to a crates.io version of defmt (check https://https://defmt.ferrous-systems.com) OR `cargo install` a _git_ version of `probe-run`: `cargo install --git https://github.com/knurling-rs/probe-run --branch main`";
-        let sem_git = "`cargo install` a non-git version of `probe-run`: `cargo install probe-run`";
-        let sem_sem = &*format!(
-            "`cargo install` a different non-git version of `probe-run` that supports defmt {}",
-            version,
-        );
-        let git_git = &*format!(
-            "pin _all_ `defmt` related dependencies to revision {0}; modify Cargo.toml files as shown below\n
-[dependencies]
-defmt = {{ git = \"https://github.com/knurling-rs/defmt\", rev = \"{0}\" }}
-defmt-rtt = {{ git = \"https://github.com/knurling-rs/defmt\", rev = \"{0}\" }}
-# ONLY pin this dependency if you are using the `print-defmt` feature
-panic-probe = {{ git = \"https://github.com/knurling-rs/defmt\", features = [\"print-defmt\"], rev = \"{0}\" }}",
-            DEFMT_VERSION
-        );
-
-        match (Kind::of(version), Kind::of(DEFMT_VERSION)) {
-            (Kind::Git, Kind::Git) => msg.push_str(git_git),
-            (Kind::Git, Kind::Semver) => msg.push_str(git_sem),
-            (Kind::Semver, Kind::Git) => msg.push_str(sem_git),
-            (Kind::Semver, Kind::Semver) => msg.push_str(sem_sem),
-        }
-
         return Err(msg);
     }
 

decoder/src/lib.rs

@@ -10,8 +10,7 @@
 #![cfg_attr(docsrs, doc(cfg(unstable)))]
 #![doc(html_logo_url = "https://knurling.ferrous-systems.com/knurling_logo_light_text.svg")]
 
-// load DEFMT_VERSION
-include!(concat!(env!("OUT_DIR"), "/version.rs"));
+pub const DEFMT_VERSION: &str = "3";
 
 mod decoder;
 mod elf2table;

defmt.x.in

@@ -27,10 +27,6 @@ SECTIONS
     /* Symbols that aren't referenced by the program and */
     /* should be placed at the end of the section */
     KEEP(*(.defmt.end .defmt.end.*));
-
-    /* $DEFMT_VERSION may contain special chars, so we quote the symbol name */
-    /* Note that the quotes actually become part of the symbol name though! */
-    "_defmt_version_ = $DEFMT_VERSION" = 1;
   }
 }
 

src/lib.rs

@@ -19,6 +19,13 @@
 extern crate alloc;
 
 // This must be in the root lib.rs, otherwise it doesn't appear in the final binary.
+
+#[used]
+#[cfg_attr(target_os = "macos", link_section = ".defmt,end.VERSION")]
+#[cfg_attr(not(target_os = "macos"), link_section = ".defmt.end")]
+#[export_name = "_defmt_version_ = 3"]
+static DEFMT_VERSION: u8 = 0;
+
 #[used]
 #[cfg_attr(target_os = "macos", link_section = ".defmt,end.ENCODING")]
 #[cfg_attr(not(target_os = "macos"), link_section = ".defmt.end")]