Exposed the rs port find method for metacall library.

viferga · viferga · commit 9070d7fc4d5d · 2025-09-09T22:32:14.000+02:00
diff --git a/source/ports/rs_port/Cargo.toml b/source/ports/rs_port/Cargo.toml
@@ -7,7 +7,7 @@ license = "Apache-2.0"
 name = "metacall"
 readme = "README.md"
 repository = "https://github.com/metacall/core/tree/develop/source/ports/rs_port"
-version = "0.5.0"
+version = "0.5.1"
 
 [lib]
 crate-type = ["lib"]
@@ -18,3 +18,6 @@ path = "src/lib.rs"
 
 [dependencies]
 metacall-inline = { path = "./inline", version = "0.2.0" }
+
+[build-dependencies]
+metacall-sys = { path = "./sys", version = "0.1.0" }
diff --git a/source/ports/rs_port/README.md b/source/ports/rs_port/README.md
@@ -15,6 +15,24 @@ MetaCall is a C plugin based library. This crate wraps the C library into Rust,
 curl -sL https://raw.githubusercontent.com/metacall/install/master/install.sh | sh
 ```
 
+# Linking
+
+If your project uses MetaCall in a folder that is not in the system path, we encourage to use `metacall-sys` crate as a `build-dependecy`. By this way you will be able to locate and link MetaCall directly in your build system. For example:
+
+`Cargo.toml`:
+```toml
+[build-dependencies]
+metacall-sys = { path = "./sys", version = "0.1.0" }
+```
+
+`build.rs`:
+```rust
+fn main() {
+    // Find MetaCall library
+    metacall_sys::build();
+}
+```
+
 # Example
 
 `sum.ts`
diff --git a/source/ports/rs_port/build.rs b/source/ports/rs_port/build.rs
@@ -1,255 +1,4 @@
-use std::{
-    env, fs,
-    path::{Path, PathBuf},
-    vec,
-};
-
-// Search for MetaCall libraries in platform-specific locations
-// Handle custom installation paths via environment variables
-// Find configuration files recursively
-// Provide helpful error messages when things aren't found
-
-/// Represents the install paths for a platform
-struct InstallPath {
-    paths: Vec<PathBuf>,
-    names: Vec<&'static str>,
-}
-
-/// Represents the match of a library when it's found
-struct LibraryPath {
-    path: PathBuf,
-    library: String,
-}
-
-/// Find files recursively in a directory matching a pattern
-fn find_files_recursively<P: AsRef<Path>>(
-    root_dir: P,
-    filename: &str,
-    max_depth: Option<usize>,
-) -> Result<Vec<PathBuf>, Box<dyn std::error::Error>> {
-    let mut matches = Vec::new();
-    let mut stack = vec![(root_dir.as_ref().to_path_buf(), 0)];
-
-    while let Some((current_dir, depth)) = stack.pop() {
-        if let Some(max) = max_depth {
-            if depth > max {
-                continue;
-            }
-        }
-
-        if let Ok(entries) = fs::read_dir(&current_dir) {
-            for entry in entries.flatten() {
-                let path = entry.path();
-
-                if path.is_file() {
-                    // Simple filename comparison instead of regex
-                    if let Some(file_name) = path.file_name().and_then(|n| n.to_str()) {
-                        if file_name == filename {
-                            matches.push(path);
-                        }
-                    }
-                } else if path.is_dir() {
-                    stack.push((path, depth + 1));
-                }
-            }
-        }
-    }
-
-    Ok(matches)
-}
-
-fn platform_install_paths() -> Result<InstallPath, Box<dyn std::error::Error>> {
-    if cfg!(target_os = "windows") {
-        // Defaults to path: C:\Users\Default\AppData\Local
-        let local_app_data = env::var("LOCALAPPDATA")
-            .unwrap_or_else(|_| String::from("C:\\Users\\Default\\AppData\\Local"));
-
-        Ok(InstallPath {
-            paths: vec![PathBuf::from(local_app_data)
-                .join("MetaCall")
-                .join("metacall")],
-            names: vec!["metacall.lib"],
-        })
-    } else if cfg!(target_os = "macos") {
-        Ok(InstallPath {
-            paths: vec![
-                PathBuf::from("/opt/homebrew/lib/"),
-                PathBuf::from("/usr/local/lib/"),
-            ],
-            names: vec!["libmetacall.dylib"],
-        })
-    } else if cfg!(target_os = "linux") {
-        Ok(InstallPath {
-            paths: vec![PathBuf::from("/usr/local/lib/"), PathBuf::from("/gnu/lib/")],
-            names: vec!["libmetacall.so"],
-        })
-    } else {
-        Err(format!("Platform {} not supported", env::consts::OS).into())
-    }
-}
-
-/// Get search paths, checking for custom installation path first
-fn get_search_config() -> Result<InstallPath, Box<dyn std::error::Error>> {
-    // First, check if user specified a custom path
-    if let Ok(custom_path) = env::var("METACALL_INSTALL_PATH") {
-        // For custom paths, we need to search for any metacall library variant
-        return Ok(InstallPath {
-            paths: vec![PathBuf::from(custom_path)],
-            names: vec![
-                "libmetacall.so",
-                "libmetacalld.so",
-                "libmetacall.dylib",
-                "libmetacalld.dylib",
-                "metacall.lib",
-                "metacalld.lib",
-            ],
-        });
-    }
-
-    // Fall back to platform-specific paths
-    platform_install_paths()
-}
-
-/// Get the parent path and library name
-fn get_parent_and_library(path: &Path) -> Option<(PathBuf, String)> {
-    let parent = path.parent()?.to_path_buf();
-
-    // Get the file stem (filename without extension)
-    let stem = path.file_stem()?.to_str()?;
-
-    // Remove "lib" prefix if present
-    let cleaned_stem = stem.strip_prefix("lib").unwrap_or(stem).to_string();
-
-    Some((parent, cleaned_stem))
-}
-
-/// Find the MetaCall library
-/// This orchestrates the search process
-fn find_metacall_library() -> Result<LibraryPath, Box<dyn std::error::Error>> {
-    let search_config = get_search_config()?;
-
-    // Search in each configured path
-    for search_path in &search_config.paths {
-        for name in &search_config.names {
-            // Search with no limit in depth
-            match find_files_recursively(search_path, name, None) {
-                Ok(files) if !files.is_empty() => {
-                    let found_lib = fs::canonicalize(&files[0])?;
-
-                    match get_parent_and_library(&found_lib) {
-                        Some((parent, name)) => {
-                            return Ok(LibraryPath {
-                                path: parent,
-                                library: name,
-                            })
-                        }
-                        None => continue,
-                    };
-                }
-                Ok(_) => {
-                    // No files found in this path, continue searching
-                    continue;
-                }
-                Err(e) => {
-                    eprintln!("Error searching in {}: {}", search_path.display(), e);
-                    continue;
-                }
-            }
-        }
-    }
-
-    // If we get here, library wasn't found
-    let search_paths: Vec<String> = search_config
-        .paths
-        .iter()
-        .map(|p| p.display().to_string())
-        .collect();
-
-    Err(format!(
-        "MetaCall library not found. Searched in: {}. \
-        If you have it installed elsewhere, set METACALL_INSTALL_PATH environment variable.",
-        search_paths.join(", ")
-    )
-    .into())
-}
-
-fn define_library_search_path(env_var: &str, separator: &str, path: &Path) -> String {
-    // Get the current value of the env var, if any
-    let existing = env::var(env_var).unwrap_or_default();
-    let path_str: String = String::from(path.to_str().unwrap());
-
-    // Append to it
-    let combined = if existing.is_empty() {
-        path_str
-    } else {
-        format!("{}{}{}", existing, separator, path_str)
-    };
-
-    format!("{}={}", env_var, combined)
-}
-
 fn main() {
-    // When running tests from CMake
-    if let Ok(val) = env::var("PROJECT_OUTPUT_DIR") {
-        // Link search path to build folder
-        println!("cargo:rustc-link-search=native={val}");
-
-        // Link against correct version of metacall
-        match env::var("CMAKE_BUILD_TYPE") {
-            Ok(val) => {
-                if val == "Debug" {
-                    // Try to link the debug version when running tests
-                    println!("cargo:rustc-link-lib=dylib=metacalld");
-                } else {
-                    println!("cargo:rustc-link-lib=dylib=metacall");
-                }
-            }
-            Err(_) => {
-                println!("cargo:rustc-link-lib=dylib=metacall");
-            }
-        }
-    } else {
-        // When building from Cargo, try to find MetaCall
-        match find_metacall_library() {
-            Ok(lib_path) => {
-                // Define linker flags
-                println!("cargo:rustc-link-search=native={}", lib_path.path.display());
-                println!("cargo:rustc-link-lib=dylib={}", lib_path.library);
-
-                // Set the runtime environment variable for finding the library during tests
-                #[cfg(target_os = "linux")]
-                const ENV_VAR: &str = "LD_LIBRARY_PATH";
-
-                #[cfg(target_os = "macos")]
-                const ENV_VAR: &str = "DYLD_LIBRARY_PATH";
-
-                #[cfg(target_os = "windows")]
-                const ENV_VAR: &str = "PATH";
-
-                #[cfg(target_os = "aix")]
-                const ENV_VAR: &str = "LIBPATH";
-
-                #[cfg(any(target_os = "linux", target_os = "macos", target_os = "aix"))]
-                const SEPARATOR: &str = ":";
-
-                #[cfg(target_os = "windows")]
-                const SEPARATOR: &str = ";";
-
-                println!(
-                    "cargo:rustc-env={}",
-                    define_library_search_path(ENV_VAR, SEPARATOR, &lib_path.path)
-                );
-            }
-            Err(e) => {
-                // Print the error
-                eprintln!(
-                    "Failed to find MetaCall library with: {e} \
-                    Still trying to link in case the library is in system paths"
-                );
-
-                // Still try to link in case the library is in system paths
-                println!("cargo:rustc-link-lib=dylib=metacall")
-            }
-        }
-    }
+    // Find MetaCall library
+    metacall_sys::build();
 }
diff --git a/source/ports/rs_port/sys/Cargo.toml b/source/ports/rs_port/sys/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "metacall-sys"
+version = "0.1.0"
+repository = "https://github.com/metacall/core/tree/develop/source/ports/rs_port"
+edition = "2021"
+license = "Apache-2.0"
+description = "Crate for finding metacall library in the system."
diff --git a/source/ports/rs_port/sys/src/lib.rs b/source/ports/rs_port/sys/src/lib.rs
diff --git a/source/ports/rs_port/upload.sh b/source/ports/rs_port/upload.sh
