fix: avoid conflict of errno with the global in <errno.h>

Author: laysakura

c_example/doc_app1/doc_app1.c

@@ -13,10 +13,10 @@
 
 void abort_with_report()
 {
-    SpringErrno errno;
+    SpringErrno errno_;
     char errmsg[1024];
-    spring_last_err(&errno, errmsg, 1024);
-    fprintf(stderr, "Error occurred (%d): %s", errno, errmsg);
+    spring_last_err(&errno_, errmsg, 1024);
+    fprintf(stderr, "Error occurred (%d): %s", errno_, errmsg);
     abort();
 }
 

c_example/doc_app2/doc_app2.c

@@ -19,10 +19,10 @@
 
 void abort_with_report()
 {
-    SpringErrno errno;
+    SpringErrno errno_;
     char errmsg[1024];
-    spring_last_err(&errno, errmsg, 1024);
-    fprintf(stderr, "Error occurred (%d): %s", errno, errmsg);
+    spring_last_err(&errno_, errmsg, 1024);
+    fprintf(stderr, "Error occurred (%d): %s", errno_, errmsg);
     abort();
 }
 

c_example/trade_projection/trade_projection.c

@@ -12,10 +12,10 @@
 
 void abort_with_report()
 {
-    SpringErrno errno;
+    SpringErrno errno_;
     char errmsg[1024];
-    spring_last_err(&errno, errmsg, 1024);
-    fprintf(stderr, "Error occurred (%d): %s", errno, errmsg);
+    spring_last_err(&errno_, errmsg, 1024);
+    fprintf(stderr, "Error occurred (%d): %s", errno_, errmsg);
     abort();
 }
 

springql.h

@@ -415,7 +415,7 @@ enum SpringErrno spring_column_bool(const SpringSinkRow *row, uint16_t i_col, bo
 enum SpringErrno spring_column_float(const SpringSinkRow *row, uint16_t i_col, float *out);
 
 /**
- * Write the most recent error number into `errno` and message into a caller-provided buffer as a UTF-8
+ * Write the most recent error number into `errno_` and message into a caller-provided buffer as a UTF-8
  * string, returning the number of bytes written.
  *
  * # Note
@@ -433,7 +433,7 @@ enum SpringErrno spring_column_float(const SpringSinkRow *row, uint16_t i_col, f
  * - `> 0`: the length of the recent error message.
  * - `< 0`: SpringErrno
  */
-int spring_last_err(enum SpringErrno *errno,
+int spring_last_err(enum SpringErrno *errno_,
                     char *errmsg,
                     int errmsg_len);
 

src/spring_last_err.rs

@@ -72,7 +72,7 @@ pub(super) fn update_last_error(err: LastError) {
     });
 }
 
-/// Write the most recent error number into `errno` and message into a caller-provided buffer as a UTF-8
+/// Write the most recent error number into `errno_` and message into a caller-provided buffer as a UTF-8
 /// string, returning the number of bytes written.
 ///
 /// # Note
@@ -91,7 +91,7 @@ pub(super) fn update_last_error(err: LastError) {
 /// - `< 0`: SpringErrno
 #[no_mangle]
 pub unsafe extern "C" fn spring_last_err(
-    errno: *mut SpringErrno,
+    errno_: *mut SpringErrno,
     errmsg: *mut c_char,
     errmsg_len: c_int,
 ) -> c_int {
@@ -103,12 +103,12 @@ pub unsafe extern "C" fn spring_last_err(
     let last_error = match take_last_error() {
         Some(err) => err,
         None => {
-            *errno = SpringErrno::Ok;
+            *errno_ = SpringErrno::Ok;
             return SpringErrno::Ok as c_int;
         }
     };
 
-    *errno = SpringErrno::from(&last_error);
+    *errno_ = SpringErrno::from(&last_error);
     let error_message = last_error.to_string();
 
     strcpy(&error_message, errmsg, errmsg_len)