Enable vsnprintf on compilers newer than 1.73.0.1 (#293)

* Add compiler version check for VaListImpl support

* Raise log level of puts

esp-wifi/build.rs

@@ -43,6 +43,41 @@ fn main() -> Result<(), String> {
     #[cfg(feature = "coex")]
     println!("cargo:rustc-cfg=coex");
 
+    let version_output = std::process::Command::new(
+        std::env::var_os("RUSTC").unwrap_or_else(|| std::ffi::OsString::from("rustc")),
+    )
+    .arg("-V")
+    .output()
+    .unwrap()
+    .stdout;
+    let version_string = String::from_utf8_lossy(&version_output);
+
+    // HACK: we detect the xtensa-enabled compiler by existence of the second version string in parens
+    // - upstream output format: rustc 1.75.0-nightly (cae0791da 2023-10-05)
+    // - xtensa output format: rustc 1.73.0-nightly (9163a2087 2023-10-03) (1.73.0.0)
+    if version_string.chars().filter(|&c| c == '(').count() == 2 {
+        let version = version_string
+            .split('(')
+            .last()
+            .unwrap()
+            .split(')')
+            .next()
+            .unwrap();
+
+        let mut version = version.split('.');
+
+        let major = version.next().unwrap().parse::<u32>().unwrap();
+        let minor = version.next().unwrap().parse::<u32>().unwrap();
+        let patch = version.next().unwrap().parse::<u32>().unwrap();
+        let release = version.next().unwrap().parse::<u32>().unwrap();
+
+        let version = Version4(major, minor, patch, release);
+
+        if version >= Version4(1, 73, 0, 1) {
+            println!("cargo:rustc-cfg=xtensa_has_vaarg");
+        }
+    }
+
     Ok(())
 }
 
@@ -57,3 +92,26 @@ fn main() -> Result<(), String> {
 fn main() {
     panic!("Select a chip via it's cargo feature");
 }
+
+use std::cmp::Ordering;
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+struct Version4(u32, u32, u32, u32);
+
+impl PartialOrd for Version4 {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        match self.0.partial_cmp(&other.0) {
+            Some(Ordering::Equal) => {}
+            ord => return ord,
+        }
+        match self.1.partial_cmp(&other.1) {
+            Some(Ordering::Equal) => {}
+            ord => return ord,
+        }
+        match self.2.partial_cmp(&other.2) {
+            Some(Ordering::Equal) => {}
+            ord => return ord,
+        }
+        self.3.partial_cmp(&other.3)
+    }
+}

esp-wifi/src/common_adapter/mod.rs

@@ -319,7 +319,7 @@ pub(crate) unsafe extern "C" fn semphr_give_from_isr(sem: *const (), hptw: *cons
 #[no_mangle]
 pub unsafe extern "C" fn puts(s: *const u8) {
     let cstr = str_from_c(s);
-    trace!("{}", cstr);
+    info!("{}", cstr);
 }
 
 #[no_mangle]

esp-wifi/src/compat/common.rs

@@ -106,15 +106,15 @@ pub unsafe fn str_from_c<'a>(s: *const u8) -> &'a str {
 
 pub unsafe extern "C" fn syslog(_priority: u32, format: *const u8, mut args: VaListImpl) {
     #[cfg(feature = "wifi-logs")]
-    {
-        #[cfg(target_arch = "riscv32")]
+    cfg_if::cfg_if! {
+        if #[cfg(any(target_arch = "riscv32", all(target_arch = "xtensa", xtensa_has_vaarg)))]
         {
             let mut buf = [0u8; 512];
             vsnprintf(&mut buf as *mut u8, 512, format, args);
             let res_str = str_from_c(&buf as *const u8);
             info!("{}", res_str);
         }
-        #[cfg(not(target_arch = "riscv32"))]
+        else
         {
             let res_str = str_from_c(format);
             info!("{}", res_str);

esp-wifi/src/wifi/os_adapter.rs

@@ -28,7 +28,6 @@ use crate::{
     timer::yield_task,
 };
 
-#[cfg(target_arch = "riscv32")]
 use crate::compat::common::syslog;
 
 use super::WifiEvent;
@@ -1508,10 +1507,7 @@ pub unsafe extern "C" fn log_write(
     _format: *const crate::binary::c_types::c_char,
     _args: ...
 ) {
-    #[cfg(not(feature = "wifi-logs"))]
-    return;
-
-    #[cfg(target_arch = "riscv32")]
+    let _args = core::mem::transmute(_args);
     syslog(_level, _format as *const u8, _args);
 }
 
@@ -1538,20 +1534,8 @@ pub unsafe extern "C" fn log_writev(
     _format: *const crate::binary::c_types::c_char,
     _args: va_list,
 ) {
-    #[cfg(feature = "wifi-logs")]
-    {
-        #[cfg(target_arch = "xtensa")]
-        {
-            let s = str_from_c(_format as *const u8);
-            info!("{}", s);
-        }
-
-        #[cfg(target_arch = "riscv32")]
-        {
-            let _args = core::mem::transmute(_args);
-            syslog(_level, _format as *const u8, _args);
-        }
-    }
+    let _args = core::mem::transmute(_args);
+    syslog(_level, _format as *const u8, _args);
 }
 
 /****************************************************************************