Implemented ferror

photon/libc/stdio/ferror.c

@@ -0,0 +1,7 @@
+#include <stdio.h>
+#include <__fio.h>
+
+int ferror(FILE *fp)
+{
+    return __fio_error(fp);
+}

photon/libc/stdio/fputs.c

@@ -5,5 +5,10 @@ int fputs(const char *str, FILE *fp)
 {
     while (*str) {
         __fio_write(fp, str++, 1);
+        if (__fio_error(fp)) {
+            return EOF;
         }
     }
+
+    return 0;
+}

photon/libc/sys/linux/__fio.h

@@ -11,11 +11,13 @@ struct __io_file {
     char buf[__FIO_BUFSZ];
     unsigned int buf_idx;
     unsigned int fd;
+    char err;
 };
 
 extern int __fileno(struct __io_file *f);
 extern unsigned int __fio_write(struct __io_file *f, const char *buf, unsigned int sz);
 extern unsigned int __fio_flush(struct __io_file *f);
+extern int __fio_error(struct __io_file *f);
 
 #if defined(__cplusplus)
 }

photon/libc/sys/linux/fio.c

@@ -40,6 +40,15 @@ unsigned int __fio_write(struct __io_file *f, const char *buf, unsigned int sz)
 
 unsigned int __fio_flush(struct __io_file *f)
 {
-    write(f->fd, f->buf, f->buf_idx);
+    ssize_t res = write(f->fd, f->buf, f->buf_idx);
+    if (res != f->buf_idx) {
+        f->err = 1;
+    }
+
     f->buf_idx = 0;
 }
+
+int __fio_error(struct __io_file *f)
+{
+    return f->err != 0;
+}