moved gdbstub to qemu - new asynchronous gdbstub

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@686 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 289 insertions, 230 deletions

diff --git a/gdbstub.c b/gdbstub.c
index 8774a9d273..0cf8395559 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -26,70 +26,36 @@
 #include <netinet/in.h>
 #include <netinet/tcp.h>
 #include <signal.h>
+#include <fcntl.h>
 
-#include "cpu.h"
-#include "exec-all.h"
+#include "vl.h"
 
 //#define DEBUG_GDB
 
-int gdbstub_fd = -1;
+enum RSState {
+    RS_IDLE,
+    RS_GETLINE,
+    RS_CHKSUM1,
+    RS_CHKSUM2,
+};
 
-/* return 0 if OK */
-static int gdbstub_open(int port)
-{
-    struct sockaddr_in sockaddr;
-    socklen_t len;
-    int fd, val, ret;
+static int gdbserver_fd;
 
-    fd = socket(PF_INET, SOCK_STREAM, 0);
-    if (fd < 0) {
-        perror("socket");
-        return -1;
-    }
+typedef struct GDBState {
+    enum RSState state;
+    int fd;
+    char line_buf[4096];
+    int line_buf_index;
+    int line_csum;
+} GDBState;
 
-    /* allow fast reuse */
-    val = 1;
-    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
-
-    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");
-        return -1;
-    }
-    ret = listen(fd, 0);
-    if (ret < 0) {
-        perror("listen");
-        return -1;
-    }
-    
-    /* now wait for one connection */
-    for(;;) {
-        len = sizeof(sockaddr);
-        gdbstub_fd = accept(fd, (struct sockaddr *)&sockaddr, &len);
-        if (gdbstub_fd < 0 && errno != EINTR) {
-            perror("accept");
-            return -1;
-        } else if (gdbstub_fd >= 0) {
-            break;
-        }
-    }
-    
-    /* set short latency */
-    val = 1;
-    setsockopt(gdbstub_fd, SOL_TCP, TCP_NODELAY, &val, sizeof(val));
-    return 0;
-}
-
-static int get_char(void)
+static int get_char(GDBState *s)
 {
     uint8_t ch;
     int ret;
 
     for(;;) {
-        ret = read(gdbstub_fd, &ch, 1);
+        ret = read(s->fd, &ch, 1);
         if (ret < 0) {
             if (errno != EINTR && errno != EAGAIN)
                 return -1;
@@ -102,12 +68,12 @@ static int get_char(void)
     return ch;
 }
 
-static void put_buffer(const uint8_t *buf, int len)
+static void put_buffer(GDBState *s, const uint8_t *buf, int len)
 {
     int ret;
 
     while (len > 0) {
-        ret = write(gdbstub_fd, buf, len);
+        ret = write(s->fd, buf, len);
         if (ret < 0) {
             if (errno != EINTR && errno != EAGAIN)
                 return;
@@ -161,59 +127,8 @@ static void hextomem(uint8_t *mem, const char *buf, int len)
     }
 }
 
-/* return -1 if error or EOF */
-static int get_packet(char *buf, int buf_size)
-{
-    int ch, len, csum, csum1;
-    char reply[1];
-    
-    for(;;) {
-        for(;;) {
-            ch = get_char();
-            if (ch < 0)
-                return -1;
-            if (ch == '$')
-                break;
-        }
-        len = 0;
-        csum = 0;
-        for(;;) {
-            ch = get_char();
-            if (ch < 0)
-                return -1;
-            if (ch == '#')
-                break;
-            if (len > buf_size - 1)
-                return -1;
-            buf[len++] = ch;
-            csum += ch;
-        }
-        buf[len] = '\0';
-        ch = get_char();
-        if (ch < 0)
-            return -1;
-        csum1 = fromhex(ch) << 4;
-        ch = get_char();
-        if (ch < 0)
-            return -1;
-        csum1 |= fromhex(ch);
-        if ((csum & 0xff) != csum1) {
-            reply[0] = '-';
-            put_buffer(reply, 1);
-        } else {
-            reply[0] = '+';
-            put_buffer(reply, 1);
-            break;
-        }
-    }
-#ifdef DEBUG_GDB
-    printf("command='%s'\n", buf);
-#endif
-    return len;
-}
-
 /* return -1 if error, 0 if OK */
-static int put_packet(char *buf)
+static int put_packet(GDBState *s, char *buf)
 {
     char buf1[3];
     int len, csum, ch, i;
@@ -224,9 +139,9 @@ static int put_packet(char *buf)
 
     for(;;) {
         buf1[0] = '$';
-        put_buffer(buf1, 1);
+        put_buffer(s, buf1, 1);
         len = strlen(buf);
-        put_buffer(buf, len);
+        put_buffer(s, buf, len);
         csum = 0;
         for(i = 0; i < len; i++) {
             csum += buf[i];
@@ -235,9 +150,9 @@ static int put_packet(char *buf)
         buf1[1] = tohex((csum >> 4) & 0xf);
         buf1[2] = tohex((csum) & 0xf);
 
-        put_buffer(buf1, 3);
+        put_buffer(s, buf1, 3);
 
-        ch = get_char();
+        ch = get_char(s);
         if (ch < 0)
             return -1;
         if (ch == '+')
@@ -387,149 +302,293 @@ static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 #endif
 
 /* port = 0 means default port */
-int cpu_gdbstub(void *opaque, int (*main_loop)(void *opaque), int port)
+static int gdb_handle_packet(GDBState *s, const char *line_buf)
 {
-    CPUState *env;
+    CPUState *env = cpu_single_env;
     const char *p;
-    int ret, ch, reg_size, type;
+    int ch, reg_size, type;
     char buf[4096];
     uint8_t mem_buf[2000];
     uint32_t *registers;
     uint32_t addr, len;
     
-    printf("Waiting gdb connection on port %d\n", port);
-    if (gdbstub_open(port) < 0)
-        return -1;
-    printf("Connected\n");
-    for(;;) {
-        ret = get_packet(buf, sizeof(buf));
-        if (ret < 0)
-            break;
-        p = buf;
-        ch = *p++;
-        switch(ch) {
-        case '?':
-            snprintf(buf, sizeof(buf), "S%02x", SIGTRAP);
-            put_packet(buf);
-            break;
-        case 'c':
-            if (*p != '\0') {
-                addr = strtoul(p, (char **)&p, 16);
-                env = cpu_gdbstub_get_env(opaque);
+#ifdef DEBUG_GDB
+    printf("command='%s'\n", line_buf);
+#endif
+    p = line_buf;
+    ch = *p++;
+    switch(ch) {
+    case '?':
+        snprintf(buf, sizeof(buf), "S%02x", SIGTRAP);
+        put_packet(s, buf);
+        break;
+    case 'c':
+        if (*p != '\0') {
+            addr = strtoul(p, (char **)&p, 16);
 #if defined(TARGET_I386)
-                env->eip = addr;
+            env->eip = addr;
 #elif defined (TARGET_PPC)
-                env->nip = addr;
+            env->nip = addr;
 #endif
-            }
-            ret = main_loop(opaque);
-            if (ret == EXCP_DEBUG)
-                ret = SIGTRAP;
-            else
-                ret = 0;
-            snprintf(buf, sizeof(buf), "S%02x", ret);
-            put_packet(buf);
-            break;
-        case 's':
-            env = cpu_gdbstub_get_env(opaque);
-            if (*p != '\0') {
-                addr = strtoul(p, (char **)&p, 16);
+        }
+        vm_start();
+        break;
+    case 's':
+        if (*p != '\0') {
+            addr = strtoul(p, (char **)&p, 16);
 #if defined(TARGET_I386)
-                env->eip = addr;
+            env->eip = addr;
 #elif defined (TARGET_PPC)
-                env->nip = addr;
+            env->nip = addr;
 #endif
+        }
+        cpu_single_step(env, 1);
+        vm_start();
+        break;
+    case 'g':
+        reg_size = cpu_gdb_read_registers(env, mem_buf);
+        memtohex(buf, mem_buf, reg_size);
+        put_packet(s, buf);
+        break;
+    case 'G':
+        registers = (void *)mem_buf;
+        len = strlen(p) / 2;
+        hextomem((uint8_t *)registers, p, len);
+        cpu_gdb_write_registers(env, mem_buf, len);
+        put_packet(s, "OK");
+        break;
+    case 'm':
+        addr = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        len = strtoul(p, NULL, 16);
+        if (cpu_memory_rw_debug(env, addr, mem_buf, len, 0) != 0)
+            memset(mem_buf, 0, len);
+        memtohex(buf, mem_buf, len);
+        put_packet(s, buf);
+        break;
+    case 'M':
+        addr = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        len = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        hextomem(mem_buf, p, len);
+        if (cpu_memory_rw_debug(env, addr, mem_buf, len, 1) != 0)
+            put_packet(s, "ENN");
+        else
+            put_packet(s, "OK");
+        break;
+    case 'Z':
+        type = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        addr = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        len = strtoul(p, (char **)&p, 16);
+        if (type == 0 || type == 1) {
+            if (cpu_breakpoint_insert(env, addr) < 0)
+                goto breakpoint_error;
+            put_packet(s, "OK");
+        } else {
+        breakpoint_error:
+            put_packet(s, "ENN");
+        }
+        break;
+    case 'z':
+        type = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        addr = strtoul(p, (char **)&p, 16);
+        if (*p == ',')
+            p++;
+        len = strtoul(p, (char **)&p, 16);
+        if (type == 0 || type == 1) {
+            cpu_breakpoint_remove(env, addr);
+            put_packet(s, "OK");
+        } else {
+            goto breakpoint_error;
+        }
+        break;
+    default:
+        //        unknown_command:
+        /* put empty packet */
+        buf[0] = '\0';
+        put_packet(s, buf);
+        break;
+    }
+    return RS_IDLE;
+}
+
+static void gdb_vm_stopped(void *opaque, int reason)
+{
+    GDBState *s = opaque;
+    char buf[256];
+    int ret;
+
+    /* disable single step if it was enable */
+    cpu_single_step(cpu_single_env, 0);
+
+    if (reason == EXCP_DEBUG)
+        ret = SIGTRAP;
+    else
+        ret = 0;
+    snprintf(buf, sizeof(buf), "S%02x", ret);
+    put_packet(s, buf);
+}
+
+static void gdb_read_byte(GDBState *s, int ch)
+{
+    int i, csum;
+    char reply[1];
+
+    if (vm_running) {
+        /* when the CPU is running, we cannot do anything except stop
+           it when receiving a char */
+        vm_stop(EXCP_INTERRUPT);
+    } else {
+        switch(s->state) {
+        case RS_IDLE:
+            if (ch == '$') {
+                s->line_buf_index = 0;
+                s->state = RS_GETLINE;
             }
-            cpu_single_step(env, 1);
-            ret = main_loop(opaque);
-            cpu_single_step(env, 0);
-            if (ret == EXCP_DEBUG)
-                ret = SIGTRAP;
-            else
-                ret = 0;
-            snprintf(buf, sizeof(buf), "S%02x", ret);
-            put_packet(buf);
-            break;
-        case 'g':
-            env = cpu_gdbstub_get_env(opaque);
-            reg_size = cpu_gdb_read_registers(env, mem_buf);
-            memtohex(buf, mem_buf, reg_size);
-            put_packet(buf);
             break;
-        case 'G':
-            env = cpu_gdbstub_get_env(opaque);
-            registers = (void *)mem_buf;
-            len = strlen(p) / 2;
-            hextomem((uint8_t *)registers, p, len);
-            cpu_gdb_write_registers(env, mem_buf, len);
-            put_packet("OK");
-            break;
-        case 'm':
-            env = cpu_gdbstub_get_env(opaque);
-            addr = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            len = strtoul(p, NULL, 16);
-            if (cpu_memory_rw_debug(env, addr, mem_buf, len, 0) != 0)
-                memset(mem_buf, 0, len);
-            memtohex(buf, mem_buf, len);
-            put_packet(buf);
-            break;
-        case 'M':
-            env = cpu_gdbstub_get_env(opaque);
-            addr = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            len = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            hextomem(mem_buf, p, len);
-            if (cpu_memory_rw_debug(env, addr, mem_buf, len, 1) != 0)
-                put_packet("ENN");
-            else
-                put_packet("OK");
-            break;
-        case 'Z':
-            type = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            addr = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            len = strtoul(p, (char **)&p, 16);
-            if (type == 0 || type == 1) {
-                env = cpu_gdbstub_get_env(opaque);
-                if (cpu_breakpoint_insert(env, addr) < 0)
-                    goto breakpoint_error;
-                put_packet("OK");
+        case RS_GETLINE:
+            if (ch == '#') {
+            s->state = RS_CHKSUM1;
+            } else if (s->line_buf_index >= sizeof(s->line_buf) - 1) {
+                s->state = RS_IDLE;
             } else {
-            breakpoint_error:
-                put_packet("ENN");
+            s->line_buf[s->line_buf_index++] = ch;
             }
             break;
-        case 'z':
-            type = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            addr = strtoul(p, (char **)&p, 16);
-            if (*p == ',')
-                p++;
-            len = strtoul(p, (char **)&p, 16);
-            if (type == 0 || type == 1) {
-                env = cpu_gdbstub_get_env(opaque);
-                cpu_breakpoint_remove(env, addr);
-                put_packet("OK");
+        case RS_CHKSUM1:
+            s->line_buf[s->line_buf_index] = '\0';
+            s->line_csum = fromhex(ch) << 4;
+            s->state = RS_CHKSUM2;
+            break;
+        case RS_CHKSUM2:
+            s->line_csum |= fromhex(ch);
+            csum = 0;
+            for(i = 0; i < s->line_buf_index; i++) {
+                csum += s->line_buf[i];
+            }
+            if (s->line_csum != (csum & 0xff)) {
+                reply[0] = '-';
+                put_buffer(s, reply, 1);
+                s->state = RS_IDLE;
             } else {
-                goto breakpoint_error;
+                reply[0] = '+';
+                put_buffer(s, reply, 1);
+                s->state = gdb_handle_packet(s, s->line_buf);
             }
             break;
-        default:
-            //        unknown_command:
-            /* put empty packet */
-            buf[0] = '\0';
-            put_packet(buf);
+        }
+    }
+}
+
+static int gdb_can_read(void *opaque)
+{
+    return 256;
+}
+
+static void gdb_read(void *opaque, const uint8_t *buf, int size)
+{
+    GDBState *s = opaque;
+    int i;
+    if (size == 0) {
+        /* end of connection */
+        qemu_del_vm_stop_handler(gdb_vm_stopped, s);
+        qemu_del_fd_read_handler(s->fd);
+        qemu_free(s);
+        vm_start();
+    } else {
+        for(i = 0; i < size; i++)
+            gdb_read_byte(s, buf[i]);
+    }
+}
+
+static void gdb_accept(void *opaque, const uint8_t *buf, int size)
+{
+    GDBState *s;
+    struct sockaddr_in sockaddr;
+    socklen_t len;
+    int val, fd;
+
+    for(;;) {
+        len = sizeof(sockaddr);
+        fd = accept(gdbserver_fd, (struct sockaddr *)&sockaddr, &len);
+        if (fd < 0 && errno != EINTR) {
+            perror("accept");
+            return;
+        } else if (fd >= 0) {
             break;
         }
     }
+
+    /* set short latency */
+    val = 1;
+    setsockopt(fd, SOL_TCP, TCP_NODELAY, &val, sizeof(val));
+    
+    s = qemu_mallocz(sizeof(GDBState));
+    if (!s) {
+        close(fd);
+        return;
+    }
+    s->fd = fd;
+
+    fcntl(fd, F_SETFL, O_NONBLOCK);
+
+    /* stop the VM */
+    vm_stop(EXCP_INTERRUPT);
+
+    /* start handling I/O */
+    qemu_add_fd_read_handler(s->fd, gdb_can_read, gdb_read, s);
+    /* when the VM is stopped, the following callback is called */
+    qemu_add_vm_stop_handler(gdb_vm_stopped, s);
+}
+
+static int gdbserver_open(int port)
+{
+    struct sockaddr_in sockaddr;
+    int fd, val, ret;
+
+    fd = socket(PF_INET, SOCK_STREAM, 0);
+    if (fd < 0) {
+        perror("socket");
+        return -1;
+    }
+
+    /* allow fast reuse */
+    val = 1;
+    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
+
+    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");
+        return -1;
+    }
+    ret = listen(fd, 0);
+    if (ret < 0) {
+        perror("listen");
+        return -1;
+    }
+    fcntl(fd, F_SETFL, O_NONBLOCK);
+    return fd;
+}
+
+int gdbserver_start(int port)
+{
+    gdbserver_fd = gdbserver_open(port);
+    if (gdbserver_fd < 0)
+        return -1;
+    /* accept connections */
+    qemu_add_fd_read_handler(gdbserver_fd, NULL, gdb_accept, NULL);
     return 0;
 }