gdbstub beginnings

src/debug/gdb_test/.gitignore

@@ -0,0 +1,2 @@
+obj/
+test-gdb

src/debug/gdb_test/Makefile

@@ -0,0 +1,25 @@
+
+default: all
+
+all: test-gdb
+
+CFLAGS += -Werror=implicit-function-declaration -Werror=int-conversion \
+    -Werror=return-type -Werror=uninitialized \
+    -I../ -Og -g -Wall \
+    -Wno-switch -Wno-pointer-sign
+
+obj/:
+	@mkdir -vp "$@"
+
+test-gdb: obj/gdbproto.o obj/gdbstub.o obj/gdbcmds.o obj/main.o
+	$(CC) $(CFLAGS) $(LDFLAGS) -o "$@" $^
+
+obj/gdb%.o: ../gdb%.c obj/
+	$(CC) $(CFLAGS) -c -o "$@" "$<"
+
+obj/main.o: main.c obj/
+	$(CC) $(CFLAGS) -c -o "$@" "$<"
+
+clean:
+	@$(RM) -rv obj/ test-gdb
+

src/debug/gdb_test/main.c

@@ -0,0 +1,94 @@
+
+#include <stdio.h>
+#include <time.h>
+
+#include "gdbstub.h"
+
+static uint32_t my_read_reg(int reg) {
+	printf("[==>] read reg %d\n", reg);
+
+	if (reg == 16) return 0x000000df; // cpsr: irq,fiq disabled, arm, sys mode
+	else return 0x69420;
+}
+static void my_write_reg(int reg, uint32_t value) {
+	printf("[==>] write reg %d: 0x%08x\n", reg, value);
+}
+static uint32_t my_read_mem(uint32_t addr, uint32_t len) {
+	printf("[==>] read mem 0x%08x (size %u)\n", addr, len);
+
+	static const uint32_t words[] = {
+		0xeafffffe,
+		0xe0211002,
+		0xe12fff1e,
+		0
+	};
+
+	// $: b $ (arm)
+	return words[(addr>>2)&3] & ((1uLL<<len)-1);
+}
+static void my_write_mem(uint32_t addr, uint32_t len, uint32_t value) {
+	printf("[==>] write addr 0x%08x (size %u): 0x%08x\n", addr, len, value);
+}
+
+void my_add_bkpt(uint32_t addr, uint32_t len) {
+	printf("[==>] add bkpt at 0x%08x, len %u\n", addr, len);
+}
+void my_del_bkpt(uint32_t addr, uint32_t len) {
+	printf("[==>] del bkpt at 0x%08x, len %u\n", addr, len);
+}
+void my_del_watchpt(uint32_t addr, uint32_t len) {
+	printf("[==>] add watchpt at 0x%08x, len %u\n", addr, len);
+}
+void my_add_watchpt(uint32_t addr, uint32_t len) {
+	printf("[==>] del watchpt at 0x%08x, len %u\n", addr, len);
+}
+
+enum gdbtgt_status my_target_get_status(void) {
+	return gdbt_break_req;
+}
+
+const static struct gdbstub_callbacks cb = {
+	.cpu = 9,
+
+	.target_get_status = my_target_get_status,
+
+	.read_reg = my_read_reg,
+	.write_reg = my_write_reg,
+	.read_mem = my_read_mem,
+	.write_mem = my_write_mem,
+	.add_bkpt = my_add_bkpt,
+	.del_bkpt = my_del_bkpt,
+	.add_watchpt = my_add_watchpt,
+	.del_watchpt = my_del_watchpt
+};
+
+int main(int argc, char** argv) {
+	struct gdbstub* stub;
+
+	stub = gdbstub_new(&cb, 3333);
+	if (!stub) return 1;
+
+	while (true) {
+		enum gdbstub_state s = gdbstub_poll(stub);
+
+		if (s == gdbstat_none || s == gdbstat_noconn) {
+			struct timespec ts;
+			ts.tv_sec = 0;
+			ts.tv_nsec = 1000*1000; // 1 ms
+			nanosleep(&ts, NULL);
+			continue;
+		}
+
+		switch (s) {
+		case gdbstat_break: printf("[==>] break execution\n"); break;
+		case gdbstat_continue: printf("[==>] continue execution\n"); break;
+		case gdbstat_disconnect: printf("[==>] disconnect\n"); break;
+		}
+
+		if (s == gdbstat_disconnect) break;
+	}
+
+	gdbstub_close(stub);
+	return 0;
+}
+