GDB hosted syscalls.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2364 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
pbrook 2007-01-28 03:10:55 +00:00
parent 4046d9130e
commit a2d1ebaf89
3 changed files with 262 additions and 32 deletions

View File

@ -61,7 +61,30 @@
#define O_BINARY 0
#endif
int open_modeflags[12] = {
#define GDB_O_RDONLY 0x000
#define GDB_O_WRONLY 0x001
#define GDB_O_RDWR 0x002
#define GDB_O_APPEND 0x008
#define GDB_O_CREAT 0x200
#define GDB_O_TRUNC 0x400
#define GDB_O_BINARY 0
static int gdb_open_modeflags[12] = {
GDB_O_RDONLY,
GDB_O_RDONLY | GDB_O_BINARY,
GDB_O_RDWR,
GDB_O_RDWR | GDB_O_BINARY,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY
};
static int open_modeflags[12] = {
O_RDONLY,
O_RDONLY | O_BINARY,
O_RDWR,
@ -142,6 +165,35 @@ static void softmmu_unlock_user(CPUState *env, void *p, target_ulong addr,
#define unlock_user(s, args, len) softmmu_unlock_user(env, s, args, len)
#endif
static target_ulong arm_semi_syscall_len;
static void arm_semi_cb(CPUState *env, target_ulong ret, target_ulong err)
{
#ifdef CONFIG_USER_ONLY
TaskState *ts = env->opaque;
#endif
if (ret == (target_ulong)-1) {
#ifdef CONFIG_USER_ONLY
ts->swi_errno = err;
#endif
env->regs[0] = ret;
} else {
/* Fixup syscalls that use nonstardard return conventions. */
switch (env->regs[0]) {
case SYS_WRITE:
case SYS_READ:
env->regs[0] = arm_semi_syscall_len - ret;
break;
case SYS_SEEK:
env->regs[0] = 0;
break;
default:
env->regs[0] = ret;
break;
}
}
}
#define ARG(n) tget32(args + (n) * 4)
#define SET_ARG(n, val) tput32(args + (n) * 4,val)
uint32_t do_arm_semihosting(CPUState *env)
@ -170,52 +222,99 @@ uint32_t do_arm_semihosting(CPUState *env)
else
return STDOUT_FILENO;
}
ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "open,%s,%x,1a4", ARG(0), (int)ARG(2),
gdb_open_modeflags[ARG(1)]);
return env->regs[0];
} else {
ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));
}
unlock_user(s, ARG(0), 0);
return ret;
case SYS_CLOSE:
return set_swi_errno(ts, close(ARG(0)));
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "close,%x", ARG(0));
return env->regs[0];
} else {
return set_swi_errno(ts, close(ARG(0)));
}
case SYS_WRITEC:
{
char c = tget8(args);
/* Write to debug console. stderr is near enough. */
return write(STDERR_FILENO, &c, 1);
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "write,2,%x,1", args);
return env->regs[0];
} else {
return write(STDERR_FILENO, &c, 1);
}
}
case SYS_WRITE0:
s = lock_user_string(args);
ret = write(STDERR_FILENO, s, strlen(s));
len = strlen(s);
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "write,2,%x,%x\n", args, len);
ret = env->regs[0];
} else {
ret = write(STDERR_FILENO, s, len);
}
unlock_user(s, args, 0);
return ret;
case SYS_WRITE:
len = ARG(2);
s = lock_user(ARG(1), len, 1);
ret = set_swi_errno(ts, write(ARG(0), s, len));
unlock_user(s, ARG(1), 0);
if (ret == (uint32_t)-1)
return -1;
return ARG(2) - ret;
if (use_gdb_syscalls()) {
arm_semi_syscall_len = len;
gdb_do_syscall(arm_semi_cb, "write,%x,%x,%x", ARG(0), ARG(1), len);
return env->regs[0];
} else {
s = lock_user(ARG(1), len, 1);
ret = set_swi_errno(ts, write(ARG(0), s, len));
unlock_user(s, ARG(1), 0);
if (ret == (uint32_t)-1)
return -1;
return len - ret;
}
case SYS_READ:
len = ARG(2);
s = lock_user(ARG(1), len, 0);
do
ret = set_swi_errno(ts, read(ARG(0), s, len));
while (ret == -1 && errno == EINTR);
unlock_user(s, ARG(1), len);
if (ret == (uint32_t)-1)
return -1;
return ARG(2) - ret;
if (use_gdb_syscalls()) {
arm_semi_syscall_len = len;
gdb_do_syscall(arm_semi_cb, "read,%x,%x,%x", ARG(0), ARG(1), len);
return env->regs[0];
} else {
s = lock_user(ARG(1), len, 0);
do
ret = set_swi_errno(ts, read(ARG(0), s, len));
while (ret == -1 && errno == EINTR);
unlock_user(s, ARG(1), len);
if (ret == (uint32_t)-1)
return -1;
return len - ret;
}
case SYS_READC:
/* XXX: Read from debug cosole. Not implemented. */
return 0;
case SYS_ISTTY:
return isatty(ARG(0));
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "isatty,%x", ARG(0));
return env->regs[0];
} else {
return isatty(ARG(0));
}
case SYS_SEEK:
ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));
if (ret == (uint32_t)-1)
return -1;
return 0;
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "fseek,%x,%x,0", ARG(0), ARG(1));
return env->regs[0];
} else {
ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));
if (ret == (uint32_t)-1)
return -1;
return 0;
}
case SYS_FLEN:
{
if (use_gdb_syscalls()) {
/* TODO: Use stat syscall. */
return -1;
} else {
struct stat buf;
ret = set_swi_errno(ts, fstat(ARG(0), &buf));
if (ret == (uint32_t)-1)
@ -226,12 +325,21 @@ uint32_t do_arm_semihosting(CPUState *env)
/* XXX: Not implemented. */
return -1;
case SYS_REMOVE:
s = lock_user_string(ARG(0));
ret = set_swi_errno(ts, remove(s));
unlock_user(s, ARG(0), 0);
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "unlink,%s", ARG(0), (int)ARG(1));
ret = env->regs[0];
} else {
s = lock_user_string(ARG(0));
ret = set_swi_errno(ts, remove(s));
unlock_user(s, ARG(0), 0);
}
return ret;
case SYS_RENAME:
{
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "rename,%s,%s",
ARG(0), (int)ARG(1), ARG(2), (int)ARG(3));
return env->regs[0];
} else {
char *s2;
s = lock_user_string(ARG(0));
s2 = lock_user_string(ARG(2));
@ -245,9 +353,14 @@ uint32_t do_arm_semihosting(CPUState *env)
case SYS_TIME:
return set_swi_errno(ts, time(NULL));
case SYS_SYSTEM:
s = lock_user_string(ARG(0));
ret = set_swi_errno(ts, system(s));
unlock_user(s, ARG(0), 0);
if (use_gdb_syscalls()) {
gdb_do_syscall(arm_semi_cb, "system,%s", ARG(0), (int)ARG(1));
return env->regs[0];
} else {
s = lock_user_string(ARG(0));
ret = set_swi_errno(ts, system(s));
unlock_user(s, ARG(0), 0);
}
case SYS_ERRNO:
#ifdef CONFIG_USER_ONLY
return ts->swi_errno;

112
gdbstub.c
View File

@ -52,6 +52,7 @@ enum RSState {
RS_GETLINE,
RS_CHKSUM1,
RS_CHKSUM2,
RS_SYSCALL,
};
typedef struct GDBState {
CPUState *env; /* current CPU */
@ -96,6 +97,27 @@ static int get_char(GDBState *s)
}
#endif
/* GDB stub state for use by semihosting syscalls. */
static GDBState *gdb_syscall_state;
static gdb_syscall_complete_cb gdb_current_syscall_cb;
enum {
GDB_SYS_UNKNOWN,
GDB_SYS_ENABLED,
GDB_SYS_DISABLED,
} gdb_syscall_mode;
/* If gdb is connected when the first semihosting syscall occurs then use
remote gdb syscalls. Otherwise use native file IO. */
int use_gdb_syscalls(void)
{
if (gdb_syscall_mode == GDB_SYS_UNKNOWN) {
gdb_syscall_mode = (gdb_syscall_state ? GDB_SYS_ENABLED
: GDB_SYS_DISABLED);
}
return gdb_syscall_mode == GDB_SYS_ENABLED;
}
static void put_buffer(GDBState *s, const uint8_t *buf, int len)
{
#ifdef CONFIG_USER_ONLY
@ -755,6 +777,34 @@ static int gdb_handle_packet(GDBState *s, CPUState *env, const char *line_buf)
vm_start();
#endif
return RS_IDLE;
case 'F':
{
target_ulong ret;
target_ulong err;
ret = strtoull(p, (char **)&p, 16);
if (*p == ',') {
p++;
err = strtoull(p, (char **)&p, 16);
} else {
err = 0;
}
if (*p == ',')
p++;
type = *p;
if (gdb_current_syscall_cb)
gdb_current_syscall_cb(s->env, ret, err);
if (type == 'C') {
put_packet(s, "T02");
} else {
#ifdef CONFIG_USER_ONLY
s->running_state = 1;
#else
vm_start();
#endif
}
}
break;
case 'g':
reg_size = cpu_gdb_read_registers(env, mem_buf);
memtohex(buf, mem_buf, reg_size);
@ -855,6 +905,9 @@ static void gdb_vm_stopped(void *opaque, int reason)
char buf[256];
int ret;
if (s->state == RS_SYSCALL)
return;
/* disable single step if it was enable */
cpu_single_step(s->env, 0);
@ -871,6 +924,60 @@ static void gdb_vm_stopped(void *opaque, int reason)
}
#endif
/* Send a gdb syscall request.
This accepts limited printf-style format specifiers, specifically:
%x - target_ulong argument printed in hex.
%s - string pointer (target_ulong) and length (int) pair. */
void gdb_do_syscall(gdb_syscall_complete_cb cb, char *fmt, ...)
{
va_list va;
char buf[256];
char *p;
target_ulong addr;
GDBState *s;
s = gdb_syscall_state;
if (!s)
return;
gdb_current_syscall_cb = cb;
s->state = RS_SYSCALL;
#ifndef CONFIG_USER_ONLY
vm_stop(EXCP_DEBUG);
#endif
s->state = RS_IDLE;
va_start(va, fmt);
p = buf;
*(p++) = 'F';
while (*fmt) {
if (*fmt == '%') {
fmt++;
switch (*fmt++) {
case 'x':
addr = va_arg(va, target_ulong);
p += sprintf(p, TARGET_FMT_lx, addr);
break;
case 's':
addr = va_arg(va, target_ulong);
p += sprintf(p, TARGET_FMT_lx "/%x", addr, va_arg(va, int));
break;
default:
fprintf(stderr, "gdbstub: Bad syscall format string '%s'\n",
fmt - 1);
break;
}
} else {
*(p++) = *(fmt++);
}
}
va_end(va);
put_packet(s, buf);
#ifdef CONFIG_USER_ONLY
gdb_handlesig(s->env, 0);
#else
cpu_interrupt(s->env, CPU_INTERRUPT_EXIT);
#endif
}
static void gdb_read_byte(GDBState *s, int ch)
{
CPUState *env = s->env;
@ -942,6 +1049,8 @@ static void gdb_read_byte(GDBState *s, int ch)
s->state = gdb_handle_packet(s, env, s->line_buf);
}
break;
default:
abort();
}
}
}
@ -1034,6 +1143,8 @@ static void gdb_accept(void *opaque)
s->env = first_cpu; /* XXX: allow to change CPU */
s->fd = fd;
gdb_syscall_state = s;
fcntl(fd, F_SETFL, O_NONBLOCK);
}
@ -1098,6 +1209,7 @@ static void gdb_chr_event(void *opaque, int event)
switch (event) {
case CHR_EVENT_RESET:
vm_stop(EXCP_INTERRUPT);
gdb_syscall_state = opaque;
break;
default:
break;

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@ -3,6 +3,11 @@
#define DEFAULT_GDBSTUB_PORT 1234
typedef void (*gdb_syscall_complete_cb)(CPUState *env,
target_ulong ret, target_ulong err);
void gdb_do_syscall(gdb_syscall_complete_cb cb, char *fmt, ...);
int use_gdb_syscalls(void);
#ifdef CONFIG_USER_ONLY
int gdb_handlesig (CPUState *, int);
void gdb_exit(CPUState *, int);