The text console receives bytes that may be UTF-8 encoded (e.g. from
a guest running a modern distro), but currently treats each byte as a
raw character index into the VGA/CP437 font, producing garbled output
for any multi-byte sequence.

Add a proper UTF-8 decoder using Bjoern Hoehrmann's DFA.
The DFA inherently rejects overlong encodings, surrogates, and
codepoints above U+10FFFF.  Completed codepoints are then mapped to
CP437, unmappable characters are displayed as '?'.

Signed-off-by: Marc-André Lureau <[email protected]>
---
 ui/cp437.h      |  13 ++++
 ui/console-vc.c |  62 +++++++++++++++++
 ui/cp437.c      | 205 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 ui/meson.build  |   2 +-
 4 files changed, 281 insertions(+), 1 deletion(-)

diff --git a/ui/cp437.h b/ui/cp437.h
new file mode 100644
index 00000000000..81ace8317c7
--- /dev/null
+++ b/ui/cp437.h
@@ -0,0 +1,13 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * Copyright (c) QEMU contributors
+ */
+#ifndef QEMU_CP437_H
+#define QEMU_CP437_H
+
+#include <stdint.h>
+
+int unicode_to_cp437(uint32_t codepoint);
+
+#endif /* QEMU_CP437_H */
diff --git a/ui/console-vc.c b/ui/console-vc.c
index 8dee1f9bd01..7bbd65dea27 100644
--- a/ui/console-vc.c
+++ b/ui/console-vc.c
@@ -9,6 +9,7 @@
 #include "qemu/fifo8.h"
 #include "qemu/option.h"
 #include "ui/console.h"
+#include "ui/cp437.h"
 
 #include "trace.h"
 #include "console-priv.h"
@@ -89,6 +90,8 @@ struct VCChardev {
     enum TTYState state;
     int esc_params[MAX_ESC_PARAMS];
     int nb_esc_params;
+    uint32_t utf8_state;     /* UTF-8 DFA decoder state */
+    uint32_t utf8_codepoint; /* accumulated UTF-8 code point */
     TextAttributes t_attrib; /* currently active text attributes */
     TextAttributes t_attrib_saved;
     int x_saved, y_saved;
@@ -598,6 +601,47 @@ static void vc_clear_xy(VCChardev *vc, int x, int y)
     vc_update_xy(vc, x, y);
 }
 
+/*
+ * UTF-8 DFA decoder by Bjoern Hoehrmann.
+ * Copyright (c) 2008-2010 Bjoern Hoehrmann <[email protected]>
+ * See https://github.com/polijan/utf8_decode for details.
+ *
+ * SPDX-License-Identifier: MIT
+ */
+#define UTF8_ACCEPT 0
+#define UTF8_REJECT 12
+
+static const uint8_t utf8d[] = {
+    /* character class lookup */
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,  9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,  7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+    8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,  2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+   10,3,3,3,3,3,3,3,3,3,3,3,3,4,3,3, 11,6,6,6,5,8,8,8,8,8,8,8,8,8,8,8,
+
+    /* state transition lookup */
+     0,12,24,36,60,96,84,12,12,12,48,72, 12,12,12,12,12,12,12,12,12,12,12,12,
+    12, 0,12,12,12,12,12, 0,12, 0,12,12, 12,24,12,12,12,12,12,24,12,24,12,12,
+    12,12,12,12,12,12,12,24,12,12,12,12, 12,24,12,12,12,12,12,12,12,24,12,12,
+    12,12,12,12,12,12,12,36,12,36,12,12, 12,36,12,12,12,12,12,36,12,36,12,12,
+    12,36,12,12,12,12,12,12,12,12,12,12,
+};
+
+static uint32_t utf8_decode(uint32_t *state, uint32_t *codep, uint32_t byte)
+{
+    uint32_t type = utf8d[byte];
+
+    *codep = (*state != UTF8_ACCEPT) ?
+        (byte & 0x3fu) | (*codep << 6) :
+        (0xffu >> type) & (byte);
+
+    *state = utf8d[256 + *state + type];
+    return *state;
+}
+
 static void vc_put_one(VCChardev *vc, int ch)
 {
     QemuTextConsole *s = vc->console;
@@ -761,6 +805,24 @@ static void vc_putchar(VCChardev *vc, int ch)
 
     switch(vc->state) {
     case TTY_STATE_NORM:
+        /* Feed byte through the UTF-8 DFA decoder */
+        if (ch >= 0x80) {
+            switch (utf8_decode(&vc->utf8_state, &vc->utf8_codepoint, ch)) {
+            case UTF8_ACCEPT:
+                vc_put_one(vc, unicode_to_cp437(vc->utf8_codepoint));
+                break;
+            case UTF8_REJECT:
+                /* Reset state so the decoder can resync */
+                vc->utf8_state = UTF8_ACCEPT;
+                break;
+            default:
+                /* Need more bytes */
+                break;
+            }
+            break;
+        }
+        /* ASCII byte: abort any pending UTF-8 sequence */
+        vc->utf8_state = UTF8_ACCEPT;
         switch(ch) {
         case '\r':  /* carriage return */
             s->x = 0;
diff --git a/ui/cp437.c b/ui/cp437.c
new file mode 100644
index 00000000000..8ec38b73419
--- /dev/null
+++ b/ui/cp437.c
@@ -0,0 +1,205 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * Copyright (c) QEMU contributors
+ */
+#include "qemu/osdep.h"
+#include "cp437.h"
+
+/*
+ * Unicode to CP437 page tables.
+ *
+ * Borrowed from the Linux kernel (fs/nls/nls_cp437.c, "Dual BSD/GPL"),
+ * generated from the Unicode Organization tables (www.unicode.org).
+ */
+static const unsigned char uni2cp437_page00[256] = {
+    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 0x00-0x07 */
+    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 0x08-0x0f */
+    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 0x10-0x17 */
+    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 0x18-0x1f */
+    0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 0x20-0x27 */
+    0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 0x28-0x2f */
+    0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 0x30-0x37 */
+    0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 0x38-0x3f */
+    0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 0x40-0x47 */
+    0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 0x48-0x4f */
+    0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 0x50-0x57 */
+    0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 0x58-0x5f */
+    0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 0x60-0x67 */
+    0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 0x68-0x6f */
+    0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 0x70-0x77 */
+    0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 0x78-0x7f */
+
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x80-0x87 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x88-0x8f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x90-0x97 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x98-0x9f */
+    0xff, 0xad, 0x9b, 0x9c, 0x00, 0x9d, 0x00, 0x00, /* 0xa0-0xa7 */
+    0x00, 0x00, 0xa6, 0xae, 0xaa, 0x00, 0x00, 0x00, /* 0xa8-0xaf */
+    0xf8, 0xf1, 0xfd, 0x00, 0x00, 0xe6, 0x00, 0xfa, /* 0xb0-0xb7 */
+    0x00, 0x00, 0xa7, 0xaf, 0xac, 0xab, 0x00, 0xa8, /* 0xb8-0xbf */
+    0x00, 0x00, 0x00, 0x00, 0x8e, 0x8f, 0x92, 0x80, /* 0xc0-0xc7 */
+    0x00, 0x90, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xc8-0xcf */
+    0x00, 0xa5, 0x00, 0x00, 0x00, 0x00, 0x99, 0x00, /* 0xd0-0xd7 */
+    0x00, 0x00, 0x00, 0x00, 0x9a, 0x00, 0x00, 0xe1, /* 0xd8-0xdf */
+    0x85, 0xa0, 0x83, 0x00, 0x84, 0x86, 0x91, 0x87, /* 0xe0-0xe7 */
+    0x8a, 0x82, 0x88, 0x89, 0x8d, 0xa1, 0x8c, 0x8b, /* 0xe8-0xef */
+    0x00, 0xa4, 0x95, 0xa2, 0x93, 0x00, 0x94, 0xf6, /* 0xf0-0xf7 */
+    0x00, 0x97, 0xa3, 0x96, 0x81, 0x00, 0x00, 0x98, /* 0xf8-0xff */
+};
+
+static const unsigned char uni2cp437_page01[256] = {
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x18-0x1f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x20-0x27 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x28-0x2f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x30-0x37 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x38-0x3f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x40-0x47 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x48-0x4f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x50-0x57 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x58-0x5f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x60-0x67 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x68-0x6f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x70-0x77 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x78-0x7f */
+
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x80-0x87 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x88-0x8f */
+    0x00, 0x00, 0x9f, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x90-0x97 */
+};
+
+static const unsigned char uni2cp437_page03[256] = {
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x18-0x1f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x20-0x27 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x28-0x2f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x30-0x37 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x38-0x3f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x40-0x47 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x48-0x4f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x50-0x57 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x58-0x5f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x60-0x67 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x68-0x6f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x70-0x77 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x78-0x7f */
+
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x80-0x87 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x88-0x8f */
+    0x00, 0x00, 0x00, 0xe2, 0x00, 0x00, 0x00, 0x00, /* 0x90-0x97 */
+    0xe9, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x98-0x9f */
+    0x00, 0x00, 0x00, 0xe4, 0x00, 0x00, 0xe8, 0x00, /* 0xa0-0xa7 */
+    0x00, 0xea, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xa8-0xaf */
+    0x00, 0xe0, 0x00, 0x00, 0xeb, 0xee, 0x00, 0x00, /* 0xb0-0xb7 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xb8-0xbf */
+    0xe3, 0x00, 0x00, 0xe5, 0xe7, 0x00, 0xed, 0x00, /* 0xc0-0xc7 */
+};
+
+static const unsigned char uni2cp437_page20[256] = {
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x18-0x1f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x20-0x27 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x28-0x2f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x30-0x37 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x38-0x3f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x40-0x47 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x48-0x4f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x50-0x57 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x58-0x5f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x60-0x67 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x68-0x6f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x70-0x77 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfc, /* 0x78-0x7f */
+
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x80-0x87 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x88-0x8f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x90-0x97 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x98-0x9f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x9e, /* 0xa0-0xa7 */
+};
+
+static const unsigned char uni2cp437_page22[256] = {
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
+    0x00, 0xf9, 0xfb, 0x00, 0x00, 0x00, 0xec, 0x00, /* 0x18-0x1f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x20-0x27 */
+    0x00, 0xef, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x28-0x2f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x30-0x37 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x38-0x3f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x40-0x47 */
+    0xf7, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x48-0x4f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x50-0x57 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x58-0x5f */
+    0x00, 0xf0, 0x00, 0x00, 0xf3, 0xf2, 0x00, 0x00, /* 0x60-0x67 */
+};
+
+static const unsigned char uni2cp437_page23[256] = {
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x08-0x0f */
+    0xa9, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x10-0x17 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x18-0x1f */
+    0xf4, 0xf5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x20-0x27 */
+};
+
+static const unsigned char uni2cp437_page25[256] = {
+    0xc4, 0x00, 0xb3, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x00-0x07 */
+    0x00, 0x00, 0x00, 0x00, 0xda, 0x00, 0x00, 0x00, /* 0x08-0x0f */
+    0xbf, 0x00, 0x00, 0x00, 0xc0, 0x00, 0x00, 0x00, /* 0x10-0x17 */
+    0xd9, 0x00, 0x00, 0x00, 0xc3, 0x00, 0x00, 0x00, /* 0x18-0x1f */
+    0x00, 0x00, 0x00, 0x00, 0xb4, 0x00, 0x00, 0x00, /* 0x20-0x27 */
+    0x00, 0x00, 0x00, 0x00, 0xc2, 0x00, 0x00, 0x00, /* 0x28-0x2f */
+    0x00, 0x00, 0x00, 0x00, 0xc1, 0x00, 0x00, 0x00, /* 0x30-0x37 */
+    0x00, 0x00, 0x00, 0x00, 0xc5, 0x00, 0x00, 0x00, /* 0x38-0x3f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x40-0x47 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x48-0x4f */
+    0xcd, 0xba, 0xd5, 0xd6, 0xc9, 0xb8, 0xb7, 0xbb, /* 0x50-0x57 */
+    0xd4, 0xd3, 0xc8, 0xbe, 0xbd, 0xbc, 0xc6, 0xc7, /* 0x58-0x5f */
+    0xcc, 0xb5, 0xb6, 0xb9, 0xd1, 0xd2, 0xcb, 0xcf, /* 0x60-0x67 */
+    0xd0, 0xca, 0xd8, 0xd7, 0xce, 0x00, 0x00, 0x00, /* 0x68-0x6f */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x70-0x77 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x78-0x7f */
+
+    0xdf, 0x00, 0x00, 0x00, 0xdc, 0x00, 0x00, 0x00, /* 0x80-0x87 */
+    0xdb, 0x00, 0x00, 0x00, 0xdd, 0x00, 0x00, 0x00, /* 0x88-0x8f */
+    0xde, 0xb0, 0xb1, 0xb2, 0x00, 0x00, 0x00, 0x00, /* 0x90-0x97 */
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0x98-0x9f */
+    0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 0xa0-0xa7 */
+};
+
+static const unsigned char *const uni2cp437_page[256] = {
+    [0x00] = uni2cp437_page00, [0x01] = uni2cp437_page01,
+    [0x03] = uni2cp437_page03, [0x20] = uni2cp437_page20,
+    [0x22] = uni2cp437_page22, [0x23] = uni2cp437_page23,
+    [0x25] = uni2cp437_page25,
+};
+
+/*
+ * Convert a Unicode code point to its CP437 equivalent for
+ * rendering with the VGA font.
+ * Returns '?' for characters that cannot be mapped.
+ */
+int unicode_to_cp437(uint32_t codepoint)
+{
+    const unsigned char *page;
+    unsigned char hi = (codepoint >> 8) & 0xff;
+    unsigned char lo = codepoint & 0xff;
+
+    if (codepoint > 0xffff) {
+        return '?';
+    }
+
+    page = uni2cp437_page[hi];
+    if (page && page[lo]) {
+        return page[lo];
+    }
+
+    return '?';
+}
diff --git a/ui/meson.build b/ui/meson.build
index 69404bca71a..d4d9312b98c 100644
--- a/ui/meson.build
+++ b/ui/meson.build
@@ -16,7 +16,7 @@ system_ss.add(files(
   'ui-qmp-cmds.c',
   'util.c',
 ))
-system_ss.add(when: pixman, if_true: files('console-vc.c'), if_false: 
files('console-vc-stubs.c'))
+system_ss.add(when: pixman, if_true: files('console-vc.c', 'cp437.c'), 
if_false: files('console-vc-stubs.c'))
 if dbus_display
   system_ss.add(files('dbus-module.c'))
 endif

-- 
2.53.0


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