diff --git a/gdbstub/gdbstub.c b/gdbstub/gdbstub.c
index 697dd4bbadec01f617373fe2a4c4894ac5c17a8f..6911b73c0799cd2cbf176a64151d4517d1443b2d 100644
--- a/gdbstub/gdbstub.c
+++ b/gdbstub/gdbstub.c
@@ -1327,6 +1327,36 @@ static const GdbCmdParseEntry gdb_v_commands_table[] = {
.cmd = "Kill;",
.cmd_startswith = 1
},
+#ifdef CONFIG_USER_ONLY
+ /*
+ * Host I/O Packets. See [1] for details.
+ * [1] https://sourceware.org/gdb/onlinedocs/gdb/Host-I_002fO-Packets.html
+ */
+ {
+ .handler = gdb_handle_v_file_open,
+ .cmd = "File:open:",
+ .cmd_startswith = 1,
+ .schema = "s,L,L0"
+ },
+ {
+ .handler = gdb_handle_v_file_close,
+ .cmd = "File:close:",
+ .cmd_startswith = 1,
+ .schema = "l0"
+ },
+ {
+ .handler = gdb_handle_v_file_pread,
+ .cmd = "File:pread:",
+ .cmd_startswith = 1,
+ .schema = "l,L,L0"
+ },
+ {
+ .handler = gdb_handle_v_file_readlink,
+ .cmd = "File:readlink:",
+ .cmd_startswith = 1,
+ .schema = "s0"
+ },
+#endif
};
static void handle_v_commands(GArray *params, void *user_ctx)
@@ -1472,11 +1502,14 @@ static void handle_query_supported(GArray *params, void *user_ctx)
";ReverseStep+;ReverseContinue+");
}
-#if defined(CONFIG_USER_ONLY) && defined(CONFIG_LINUX)
+#if defined(CONFIG_USER_ONLY)
+#if defined(CONFIG_LINUX)
if (gdbserver_state.c_cpu->opaque) {
g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+");
}
#endif
+ g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+");
+#endif
if (params->len &&
strstr(get_param(params, 0)->data, "multiprocess+")) {
@@ -1615,13 +1648,21 @@ static const GdbCmdParseEntry gdb_gen_query_table[] = {
.cmd_startswith = 1,
.schema = "s:l,l0"
},
-#if defined(CONFIG_USER_ONLY) && defined(CONFIG_LINUX)
+#if defined(CONFIG_USER_ONLY)
+#if defined(CONFIG_LINUX)
{
.handler = gdb_handle_query_xfer_auxv,
.cmd = "Xfer:auxv:read::",
.cmd_startswith = 1,
.schema = "l,l0"
},
+#endif
+ {
+ .handler = gdb_handle_query_xfer_exec_file,
+ .cmd = "Xfer:exec-file:read:",
+ .cmd_startswith = 1,
+ .schema = "l:l,l0"
+ },
#endif
{
.handler = gdb_handle_query_attached,
diff --git a/gdbstub/internals.h b/gdbstub/internals.h
index 25e4d5eeaa667edda578f58c1bad473d86af9793..f2b46cce4123efcda8e4e25ec2a762cf61cd11bc 100644
--- a/gdbstub/internals.h
+++ b/gdbstub/internals.h
@@ -189,6 +189,11 @@ typedef union GdbCmdVariant {
void gdb_handle_query_rcmd(GArray *params, void *user_ctx); /* softmmu */
void gdb_handle_query_offsets(GArray *params, void *user_ctx); /* user */
void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx); /*user */
+void gdb_handle_v_file_open(GArray *params, void *user_ctx); /* user */
+void gdb_handle_v_file_close(GArray *params, void *user_ctx); /* user */
+void gdb_handle_v_file_pread(GArray *params, void *user_ctx); /* user */
+void gdb_handle_v_file_readlink(GArray *params, void *user_ctx); /* user */
+void gdb_handle_query_xfer_exec_file(GArray *params, void *user_ctx); /* user */
void gdb_handle_query_attached(GArray *params, void *user_ctx); /* both */
diff --git a/gdbstub/user-target.c b/gdbstub/user-target.c
index fa0e59ec9a5363bad4dd51198af5ccbb8da8f5a8..6e21c3161c2bb7824867bc9de9c4485405bf1958 100644
--- a/gdbstub/user-target.c
+++ b/gdbstub/user-target.c
@@ -11,6 +11,10 @@
#include "exec/gdbstub.h"
#include "qemu.h"
#include "internals.h"
+#ifdef CONFIG_LINUX
+#include "linux-user/loader.h"
+#include "linux-user/qemu.h"
+#endif
/*
* Map target signal numbers to GDB protocol signal numbers and vice
@@ -281,3 +285,136 @@ void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx)
gdbserver_state.str_buf->len, true);
}
#endif
+
+static const char *get_filename_param(GArray *params, int i)
+{
+ const char *hex_filename = get_param(params, i)->data;
+ gdb_hextomem(gdbserver_state.mem_buf, hex_filename,
+ strlen(hex_filename) / 2);
+ g_byte_array_append(gdbserver_state.mem_buf, (const guint8 *)"", 1);
+ return (const char *)gdbserver_state.mem_buf->data;
+}
+
+static void hostio_reply_with_data(const void *buf, size_t n)
+{
+ g_string_printf(gdbserver_state.str_buf, "F%zx;", n);
+ gdb_memtox(gdbserver_state.str_buf, buf, n);
+ gdb_put_packet_binary(gdbserver_state.str_buf->str,
+ gdbserver_state.str_buf->len, true);
+}
+
+void gdb_handle_v_file_open(GArray *params, void *user_ctx)
+{
+ const char *filename = get_filename_param(params, 0);
+ uint64_t flags = get_param(params, 1)->val_ull;
+ uint64_t mode = get_param(params, 2)->val_ull;
+
+#ifdef CONFIG_LINUX
+ int fd = do_guest_openat(gdbserver_state.g_cpu->env_ptr, 0, filename,
+ flags, mode, false);
+#else
+ int fd = open(filename, flags, mode);
+#endif
+ if (fd < 0) {
+ g_string_printf(gdbserver_state.str_buf, "F-1,%d", errno);
+ } else {
+ g_string_printf(gdbserver_state.str_buf, "F%d", fd);
+ }
+ gdb_put_strbuf();
+}
+
+void gdb_handle_v_file_close(GArray *params, void *user_ctx)
+{
+ int fd = get_param(params, 0)->val_ul;
+
+ if (close(fd) == -1) {
+ g_string_printf(gdbserver_state.str_buf, "F-1,%d", errno);
+ gdb_put_strbuf();
+ return;
+ }
+
+ gdb_put_packet("F00");
+}
+
+void gdb_handle_v_file_pread(GArray *params, void *user_ctx)
+{
+ int fd = get_param(params, 0)->val_ul;
+ size_t count = get_param(params, 1)->val_ull;
+ off_t offset = get_param(params, 2)->val_ull;
+
+ size_t bufsiz = MIN(count, BUFSIZ);
+ g_autofree char *buf = g_try_malloc(bufsiz);
+ if (buf == NULL) {
+ gdb_put_packet("E12");
+ return;
+ }
+
+ ssize_t n = pread(fd, buf, bufsiz, offset);
+ if (n < 0) {
+ g_string_printf(gdbserver_state.str_buf, "F-1,%d", errno);
+ gdb_put_strbuf();
+ return;
+ }
+ hostio_reply_with_data(buf, n);
+}
+
+void gdb_handle_v_file_readlink(GArray *params, void *user_ctx)
+{
+ const char *filename = get_filename_param(params, 0);
+
+ g_autofree char *buf = g_try_malloc(BUFSIZ);
+ if (buf == NULL) {
+ gdb_put_packet("E12");
+ return;
+ }
+
+#ifdef CONFIG_LINUX
+ ssize_t n = do_guest_readlink(filename, buf, BUFSIZ);
+#else
+ ssize_t n = readlink(filename, buf, BUFSIZ);
+#endif
+ if (n < 0) {
+ g_string_printf(gdbserver_state.str_buf, "F-1,%d", errno);
+ gdb_put_strbuf();
+ return;
+ }
+ hostio_reply_with_data(buf, n);
+}
+
+void gdb_handle_query_xfer_exec_file(GArray *params, void *user_ctx)
+{
+ uint32_t pid = get_param(params, 0)->val_ul;
+ uint32_t offset = get_param(params, 1)->val_ul;
+ uint32_t length = get_param(params, 2)->val_ul;
+
+ GDBProcess *process = gdb_get_process(pid);
+ if (!process) {
+ gdb_put_packet("E00");
+ return;
+ }
+
+ CPUState *cpu = gdb_get_first_cpu_in_process(process);
+ if (!cpu) {
+ gdb_put_packet("E00");
+ return;
+ }
+
+ TaskState *ts = cpu->opaque;
+ if (!ts || !ts->bprm || !ts->bprm->filename) {
+ gdb_put_packet("E00");
+ return;
+ }
+
+ size_t total_length = strlen(ts->bprm->filename);
+ if (offset > total_length) {
+ gdb_put_packet("E00");
+ return;
+ }
+ if (offset + length > total_length) {
+ length = total_length - offset;
+ }
+
+ g_string_printf(gdbserver_state.str_buf, "l%.*s", length,
+ ts->bprm->filename + offset);
+ gdb_put_strbuf();
+}