gdbstub: Introduce GDBFeatureBuilder

GDBFeatureBuilder unifies the logic to generate dynamic GDBFeature.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231025093128.33116-4-akihiko.odaki@daynix.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231106185112.2755262-11-alex.bennee@linaro.org>

1 files changed, 65 insertions, 0 deletions

diff --git a/gdbstub/gdbstub.c b/gdbstub/gdbstub.c
index ae24c48..ebb912d 100644
--- a/gdbstub/gdbstub.c
+++ b/gdbstub/gdbstub.c
@@ -422,6 +422,71 @@ static const char *get_feature_xml(const char *p, const char **newp,
     return NULL;
 }
 
+void gdb_feature_builder_init(GDBFeatureBuilder *builder, GDBFeature *feature,
+                              const char *name, const char *xmlname,
+                              int base_reg)
+{
+    char *header = g_markup_printf_escaped(
+        "<?xml version=\"1.0\"?>"
+        "<!DOCTYPE feature SYSTEM \"gdb-target.dtd\">"
+        "<feature name=\"%s\">",
+        name);
+
+    builder->feature = feature;
+    builder->xml = g_ptr_array_new();
+    g_ptr_array_add(builder->xml, header);
+    builder->base_reg = base_reg;
+    feature->xmlname = xmlname;
+    feature->num_regs = 0;
+}
+
+void gdb_feature_builder_append_tag(const GDBFeatureBuilder *builder,
+                                    const char *format, ...)
+{
+    va_list ap;
+    va_start(ap, format);
+    g_ptr_array_add(builder->xml, g_markup_vprintf_escaped(format, ap));
+    va_end(ap);
+}
+
+void gdb_feature_builder_append_reg(const GDBFeatureBuilder *builder,
+                                    const char *name,
+                                    int bitsize,
+                                    int regnum,
+                                    const char *type,
+                                    const char *group)
+{
+    if (builder->feature->num_regs < regnum) {
+        builder->feature->num_regs = regnum;
+    }
+
+    if (group) {
+        gdb_feature_builder_append_tag(
+            builder,
+            "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\" group=\"%s\"/>",
+            name, bitsize, builder->base_reg + regnum, type, group);
+    } else {
+        gdb_feature_builder_append_tag(
+            builder,
+            "<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\"/>",
+            name, bitsize, builder->base_reg + regnum, type);
+    }
+}
+
+void gdb_feature_builder_end(const GDBFeatureBuilder *builder)
+{
+    g_ptr_array_add(builder->xml, (void *)"</feature>");
+    g_ptr_array_add(builder->xml, NULL);
+
+    builder->feature->xml = g_strjoinv(NULL, (void *)builder->xml->pdata);
+
+    for (guint i = 0; i < builder->xml->len - 2; i++) {
+        g_free(g_ptr_array_index(builder->xml, i));
+    }
+
+    g_ptr_array_free(builder->xml, TRUE);
+}
+
 const GDBFeature *gdb_find_static_feature(const char *xmlname)
 {
     const GDBFeature *feature;