semihosting: Create qemu_semihosting_console_write

Will replace qemu_semihosting_console_{outs,outc},
but we need more plumbing first.

Reviewed-by: Luc Michel <lmichel@kalray.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

include/semihosting/console.h

@@ -54,6 +54,18 @@ void qemu_semihosting_console_outc(CPUArchState *env, target_ulong c);
  */
 int qemu_semihosting_console_read(CPUState *cs, void *buf, int len);
 
+/**
+ * qemu_semihosting_console_write:
+ * @buf: host buffer
+ * @len: buffer size
+ *
+ * Write len bytes from buf to the debug console.
+ *
+ * Returns: number of bytes written -- this should only ever be short
+ * on some sort of i/o error.
+ */
+int qemu_semihosting_console_write(void *buf, int len);
+
 /**
  * qemu_semihosting_log_out:
  * @s: pointer to string

linux-user/semihost.c

@@ -76,3 +76,8 @@ int qemu_semihosting_console_read(CPUState *cs, void *buf, int len)
 
     return ret;
 }
+
+int qemu_semihosting_console_write(void *buf, int len)
+{
+    return fwrite(buf, 1, len, stderr);
+}

semihosting/console.c

@@ -169,6 +169,15 @@ int qemu_semihosting_console_read(CPUState *cs, void *buf, int len)
     return ret;
 }
 
+int qemu_semihosting_console_write(void *buf, int len)
+{
+    if (console.chr) {
+        return qemu_chr_write_all(console.chr, (uint8_t *)buf, len);
+    } else {
+        return fwrite(buf, 1, len, stderr);
+    }
+}
+
 void qemu_semihosting_console_init(Chardev *chr)
 {
     console.chr = chr;