gdbstub: Introduce GDBFeature structure

Before this change, the information from a XML file was stored in an
array that is not descriptive. Introduce a dedicated structure type to
make it easier to understand and to extend with more fields.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230912224107.29669-6-akihiko.odaki@daynix.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231009164104.369749-13-alex.bennee@linaro.org>

MAINTAINERS

@@ -2842,7 +2842,7 @@ F: include/exec/gdbstub.h
 F: include/gdbstub/*
 F: gdb-xml/
 F: tests/tcg/multiarch/gdbstub/
-F: scripts/feature_to_c.sh
+F: scripts/feature_to_c.py
 F: scripts/probe-gdb-support.py
 
 Memory API

gdbstub/gdbstub.c

@@ -408,11 +408,11 @@ static const char *get_feature_xml(const char *p, const char **newp,
         }
     }
     /* Is it one of the encoded gdb-xml/ files? */
-    for (int i = 0; xml_builtin[i][0]; i++) {
-        const char *name = xml_builtin[i][0];
+    for (int i = 0; gdb_static_features[i].xmlname; i++) {
+        const char *name = gdb_static_features[i].xmlname;
         if ((strncmp(name, p, len) == 0) &&
             strlen(name) == len) {
-            return xml_builtin[i][1];
+            return gdb_static_features[i].xml;
         }
     }
 

include/exec/gdbstub.h

@@ -10,6 +10,11 @@
 #define GDB_WATCHPOINT_READ      3
 #define GDB_WATCHPOINT_ACCESS    4
 
+typedef struct GDBFeature {
+    const char *xmlname;
+    const char *xml;
+} GDBFeature;
+
 
 /* Get or set a register.  Returns the size of the register.  */
 typedef int (*gdb_get_reg_cb)(CPUArchState *env, GByteArray *buf, int reg);
@@ -48,7 +53,7 @@ void gdb_set_stop_cpu(CPUState *cpu);
  */
 bool gdb_has_xml(void);
 
-/* in gdbstub-xml.c, generated by scripts/feature_to_c.sh */
-extern const char *const xml_builtin[][2];
+/* in gdbstub-xml.c, generated by scripts/feature_to_c.py */
+extern const GDBFeature gdb_static_features[];
 
 #endif

meson.build

@@ -3693,7 +3693,7 @@ common_all = static_library('common',
                             dependencies: common_all.dependencies(),
                             name_suffix: 'fa')
 
-feature_to_c = find_program('scripts/feature_to_c.sh')
+feature_to_c = find_program('scripts/feature_to_c.py')
 
 if targetos == 'darwin'
   entitlement = find_program('scripts/entitlement.sh')

scripts/feature_to_c.py

@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+import os, sys
+
+def writeliteral(indent, bytes):
+    sys.stdout.write(' ' * indent)
+    sys.stdout.write('"')
+    quoted = True
+
+    for c in bytes:
+        if not quoted:
+            sys.stdout.write('\n')
+            sys.stdout.write(' ' * indent)
+            sys.stdout.write('"')
+            quoted = True
+
+        if c == b'"'[0]:
+            sys.stdout.write('\\"')
+        elif c == b'\\'[0]:
+            sys.stdout.write('\\\\')
+        elif c == b'\n'[0]:
+            sys.stdout.write('\\n"')
+            quoted = False
+        elif c >= 32 and c < 127:
+            sys.stdout.write(c.to_bytes(1, 'big').decode())
+        else:
+            sys.stdout.write(f'\{c:03o}')
+
+    if quoted:
+        sys.stdout.write('"')
+
+sys.stdout.write('#include "qemu/osdep.h"\n' \
+                 '#include "exec/gdbstub.h"\n' \
+                 '\n'
+                 'const GDBFeature gdb_static_features[] = {\n')
+
+for input in sys.argv[1:]:
+    with open(input, 'rb') as file:
+        read = file.read()
+
+    sys.stdout.write('    {\n')
+    writeliteral(8, bytes(os.path.basename(input), 'utf-8'))
+    sys.stdout.write(',\n')
+    writeliteral(8, read)
+    sys.stdout.write('\n    },\n')
+
+sys.stdout.write('    { NULL }\n};\n')

stubs/gdbstub.c

@@ -1,6 +1,6 @@
 #include "qemu/osdep.h"
-#include "exec/gdbstub.h"       /* xml_builtin */
+#include "exec/gdbstub.h"       /* gdb_static_features */
 
-const char *const xml_builtin[][2] = {
-  { NULL, NULL }
+const GDBFeature gdb_static_features[] = {
+  { NULL }
 };