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Diffstat (limited to 'payloads/libpayload/gdb/commands.c')
-rw-r--r--payloads/libpayload/gdb/commands.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/payloads/libpayload/gdb/commands.c b/payloads/libpayload/gdb/commands.c
new file mode 100644
index 0000000000..5137dfd9f5
--- /dev/null
+++ b/payloads/libpayload/gdb/commands.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but without any warranty; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <arch/cache.h>
+#include <gdb.h>
+#include <libpayload.h>
+
+static void gdb_get_last_signal(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ gdb_message_add_string(reply, "S");
+ gdb_message_encode_bytes(reply, &gdb_state.signal, 1);
+}
+
+static void gdb_read_general_registers(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ gdb_arch_encode_regs(reply);
+}
+
+static void gdb_write_general_registers(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ gdb_arch_decode_regs(offset, command);
+ gdb_message_add_string(reply, "OK");
+}
+
+static void gdb_read_memory(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ int tok = gdb_message_tokenize(command, &offset);
+ uintptr_t addr = gdb_message_decode_int(command, tok, offset - 1 - tok);
+ size_t length = gdb_message_decode_int(command, offset,
+ command->used - offset);
+
+ gdb_message_encode_bytes(reply, (void *)addr, length);
+}
+
+static void gdb_write_memory(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ int tok = gdb_message_tokenize(command, &offset);
+ uintptr_t addr = gdb_message_decode_int(command, tok, offset - 1 - tok);
+ tok = gdb_message_tokenize(command, &offset);
+ size_t length = gdb_message_decode_int(command, tok, offset - 1 - tok);
+
+ die_if(length * 2 != command->used - offset, "Invalid length field in "
+ "GDB command: %.*s", command->used, command->buf);
+
+ gdb_message_decode_bytes(command, offset, (void *)addr, length);
+ cache_sync_instructions();
+ gdb_message_add_string(reply, "OK");
+}
+
+static void gdb_continue(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ /* Disable single step if it's still on. */
+ gdb_arch_set_single_step(0);
+
+ /* No need to support the extension that passes in new EIP/PC. */
+ if (command->used > offset)
+ gdb_message_add_string(reply, "E00");
+ else
+ gdb_state.resumed = 1;
+}
+
+static void gdb_single_step(struct gdb_message *command,
+ int offset, struct gdb_message *reply)
+{
+ if (command->used > offset || gdb_arch_set_single_step(1))
+ gdb_message_add_string(reply, "E00");
+ else
+ gdb_state.resumed = 1;
+}
+
+struct gdb_command gdb_commands[] = {
+ { "?", &gdb_get_last_signal },
+ { "g", &gdb_read_general_registers },
+ { "G", &gdb_write_general_registers },
+ { "m", &gdb_read_memory },
+ { "M", &gdb_write_memory },
+ { "c", &gdb_continue },
+ { "s", &gdb_single_step }
+};
+const int gdb_command_count = ARRAY_SIZE(gdb_commands);