diff options
Diffstat (limited to 'gdbstub/user.c')
-rw-r--r-- | gdbstub/user.c | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/gdbstub/user.c b/gdbstub/user.c index 09a18fb23b..23b2e726f6 100644 --- a/gdbstub/user.c +++ b/gdbstub/user.c @@ -10,10 +10,354 @@ */ #include "qemu/osdep.h" +#include "qemu/cutils.h" +#include "qemu/sockets.h" +#include "exec/hwaddr.h" +#include "exec/tb-flush.h" #include "exec/gdbstub.h" +#include "gdbstub/user.h" #include "hw/core/cpu.h" +#include "trace.h" #include "internals.h" +/* User-mode specific state */ +typedef struct { + int fd; + char *socket_path; + int running_state; +} GDBUserState; + +static GDBUserState gdbserver_user_state; + +int gdb_get_char(void) +{ + uint8_t ch; + int ret; + + for (;;) { + ret = recv(gdbserver_user_state.fd, &ch, 1, 0); + if (ret < 0) { + if (errno == ECONNRESET) { + gdbserver_user_state.fd = -1; + } + if (errno != EINTR) { + return -1; + } + } else if (ret == 0) { + close(gdbserver_user_state.fd); + gdbserver_user_state.fd = -1; + return -1; + } else { + break; + } + } + return ch; +} + +void gdb_put_buffer(const uint8_t *buf, int len) +{ + int ret; + + while (len > 0) { + ret = send(gdbserver_user_state.fd, buf, len, 0); + if (ret < 0) { + if (errno != EINTR) { + return; + } + } else { + buf += ret; + len -= ret; + } + } +} + +/* Tell the remote gdb that the process has exited. */ +void gdb_exit(int code) +{ + char buf[4]; + + if (!gdbserver_state.init) { + return; + } + if (gdbserver_user_state.socket_path) { + unlink(gdbserver_user_state.socket_path); + } + if (gdbserver_user_state.fd < 0) { + return; + } + + trace_gdbstub_op_exiting((uint8_t)code); + + snprintf(buf, sizeof(buf), "W%02x", (uint8_t)code); + gdb_put_packet(buf); +} + +int gdb_handlesig(CPUState *cpu, int sig) +{ + char buf[256]; + int n; + + if (!gdbserver_state.init || gdbserver_user_state.fd < 0) { + return sig; + } + + /* disable single step if it was enabled */ + cpu_single_step(cpu, 0); + tb_flush(cpu); + + if (sig != 0) { + gdb_set_stop_cpu(cpu); + g_string_printf(gdbserver_state.str_buf, + "T%02xthread:", gdb_target_signal_to_gdb(sig)); + gdb_append_thread_id(cpu, gdbserver_state.str_buf); + g_string_append_c(gdbserver_state.str_buf, ';'); + gdb_put_strbuf(); + } + /* + * gdb_put_packet() might have detected that the peer terminated the + * connection. + */ + if (gdbserver_user_state.fd < 0) { + return sig; + } + + sig = 0; + gdbserver_state.state = RS_IDLE; + gdbserver_user_state.running_state = 0; + while (gdbserver_user_state.running_state == 0) { + n = read(gdbserver_user_state.fd, buf, 256); + if (n > 0) { + int i; + + for (i = 0; i < n; i++) { + gdb_read_byte(buf[i]); + } + } else { + /* + * XXX: Connection closed. Should probably wait for another + * connection before continuing. + */ + if (n == 0) { + close(gdbserver_user_state.fd); + } + gdbserver_user_state.fd = -1; + return sig; + } + } + sig = gdbserver_state.signal; + gdbserver_state.signal = 0; + return sig; +} + +/* Tell the remote gdb that the process has exited due to SIG. */ +void gdb_signalled(CPUArchState *env, int sig) +{ + char buf[4]; + + if (!gdbserver_state.init || gdbserver_user_state.fd < 0) { + return; + } + + snprintf(buf, sizeof(buf), "X%02x", gdb_target_signal_to_gdb(sig)); + gdb_put_packet(buf); +} + +static void gdb_accept_init(int fd) +{ + gdb_init_gdbserver_state(); + gdb_create_default_process(&gdbserver_state); + gdbserver_state.processes[0].attached = true; + gdbserver_state.c_cpu = gdb_first_attached_cpu(); + gdbserver_state.g_cpu = gdbserver_state.c_cpu; + gdbserver_user_state.fd = fd; + gdb_has_xml = false; +} + +static bool gdb_accept_socket(int gdb_fd) +{ + int fd; + + for (;;) { + fd = accept(gdb_fd, NULL, NULL); + if (fd < 0 && errno != EINTR) { + perror("accept socket"); + return false; + } else if (fd >= 0) { + qemu_set_cloexec(fd); + break; + } + } + + gdb_accept_init(fd); + return true; +} + +static int gdbserver_open_socket(const char *path) +{ + struct sockaddr_un sockaddr = {}; + int fd, ret; + + fd = socket(AF_UNIX, SOCK_STREAM, 0); + if (fd < 0) { + perror("create socket"); + return -1; + } + + sockaddr.sun_family = AF_UNIX; + pstrcpy(sockaddr.sun_path, sizeof(sockaddr.sun_path) - 1, path); + ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr)); + if (ret < 0) { + perror("bind socket"); + close(fd); + return -1; + } + ret = listen(fd, 1); + if (ret < 0) { + perror("listen socket"); + close(fd); + return -1; + } + + return fd; +} + +static bool gdb_accept_tcp(int gdb_fd) +{ + struct sockaddr_in sockaddr = {}; + socklen_t len; + int fd; + + for (;;) { + len = sizeof(sockaddr); + fd = accept(gdb_fd, (struct sockaddr *)&sockaddr, &len); + if (fd < 0 && errno != EINTR) { + perror("accept"); + return false; + } else if (fd >= 0) { + qemu_set_cloexec(fd); + break; + } + } + + /* set short latency */ + if (socket_set_nodelay(fd)) { + perror("setsockopt"); + close(fd); + return false; + } + + gdb_accept_init(fd); + return true; +} + +static int gdbserver_open_port(int port) +{ + struct sockaddr_in sockaddr; + int fd, ret; + + fd = socket(PF_INET, SOCK_STREAM, 0); + if (fd < 0) { + perror("socket"); + return -1; + } + qemu_set_cloexec(fd); + + socket_set_fast_reuse(fd); + + sockaddr.sin_family = AF_INET; + sockaddr.sin_port = htons(port); + sockaddr.sin_addr.s_addr = 0; + ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr)); + if (ret < 0) { + perror("bind"); + close(fd); + return -1; + } + ret = listen(fd, 1); + if (ret < 0) { + perror("listen"); + close(fd); + return -1; + } + + return fd; +} + +int gdbserver_start(const char *port_or_path) +{ + int port = g_ascii_strtoull(port_or_path, NULL, 10); + int gdb_fd; + + if (port > 0) { + gdb_fd = gdbserver_open_port(port); + } else { + gdb_fd = gdbserver_open_socket(port_or_path); + } + + if (gdb_fd < 0) { + return -1; + } + + if (port > 0 && gdb_accept_tcp(gdb_fd)) { + return 0; + } else if (gdb_accept_socket(gdb_fd)) { + gdbserver_user_state.socket_path = g_strdup(port_or_path); + return 0; + } + + /* gone wrong */ + close(gdb_fd); + return -1; +} + +/* Disable gdb stub for child processes. */ +void gdbserver_fork(CPUState *cpu) +{ + if (!gdbserver_state.init || gdbserver_user_state.fd < 0) { + return; + } + close(gdbserver_user_state.fd); + gdbserver_user_state.fd = -1; + cpu_breakpoint_remove_all(cpu, BP_GDB); + /* no cpu_watchpoint_remove_all for user-mode */ +} + +/* + * Execution state helpers + */ + +void gdb_continue(void) +{ + gdbserver_user_state.running_state = 1; + trace_gdbstub_op_continue(); +} + +/* + * Resume execution, for user-mode emulation it's equivalent to + * gdb_continue. + */ +int gdb_continue_partial(char *newstates) +{ + CPUState *cpu; + int res = 0; + /* + * This is not exactly accurate, but it's an improvement compared to the + * previous situation, where only one CPU would be single-stepped. + */ + CPU_FOREACH(cpu) { + if (newstates[cpu->cpu_index] == 's') { + trace_gdbstub_op_stepping(cpu->cpu_index); + cpu_single_step(cpu, gdbserver_state.sstep_flags); + } + } + gdbserver_user_state.running_state = 1; + return res; +} + +/* + * Break/Watch point helpers + */ + bool gdb_supports_guest_debug(void) { /* user-mode == TCG == supported */ |