gdb_server: Support vRun packet, allow setting cmdline from GDB

GDB uses the vRun packet if available to restart a running process in
extended remote mode. Support this like the R packet and set the
semihosting command-line to allow it to be specified from GDB.

Change-Id: I9cb812b22170630f782113c9927e46e0cd5b1f0f
Signed-off-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
Reviewed-on: http://openocd.zylin.com/5186
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

diff --git a/src/server/gdb_server.c b/src/server/gdb_server.c
index 0370fcd5bbe1c979e3518cab92e87857e8b3076d..c8f0e523ce63805f93d1fea07aacdfee2fd1e2cf 100644 (file)
--- a/src/server/gdb_server.c
+++ b/src/server/gdb_server.c
@@ -43,6 +43,7 @@
 #include <target/register.h>
 #include <target/target.h>
 #include <target/target_type.h>
+#include <target/semihosting_common.h>
 #include "server.h"
 #include <flash/nor/core.h>
 #include "gdb_server.h"
@@ -2887,6 +2888,96 @@ static bool gdb_handle_vcont_packet(struct connection *connection, const char *p
        return false;
 }
 
+static char *next_hex_encoded_field(const char **str, char sep)
+{
+       size_t hexlen;
+       const char *hex = *str;
+       if (hex[0] == '\0')
+               return NULL;
+
+       const char *end = strchr(hex, sep);
+       if (end == NULL)
+               hexlen = strlen(hex);
+       else
+               hexlen = end - hex;
+       *str = hex + hexlen + 1;
+
+       if (hexlen % 2 != 0) {
+               /* Malformed hex data */
+               return NULL;
+       }
+
+       size_t count = hexlen / 2;
+       char *decoded = malloc(count + 1);
+       if (decoded == NULL)
+               return NULL;
+
+       size_t converted = unhexify((void *)decoded, hex, count);
+       if (converted != count) {
+               free(decoded);
+               return NULL;
+       }
+
+       decoded[count] = '\0';
+       return decoded;
+}
+
+/* handle extended restart packet */
+static void gdb_restart_inferior(struct connection *connection, const char *packet, int packet_size)
+{
+       struct gdb_connection *gdb_con = connection->priv;
+       struct target *target = get_target_from_connection(connection);
+
+       breakpoint_clear_target(target);
+       watchpoint_clear_target(target);
+       command_run_linef(connection->cmd_ctx, "ocd_gdb_restart %s",
+                       target_name(target));
+       /* set connection as attached after reset */
+       gdb_con->attached = true;
+       /*  info rtos parts */
+       gdb_thread_packet(connection, packet, packet_size);
+}
+
+static bool gdb_handle_vrun_packet(struct connection *connection, const char *packet, int packet_size)
+{
+       struct target *target = get_target_from_connection(connection);
+       const char *parse = packet;
+
+       /* Skip "vRun" */
+       parse += 4;
+
+       if (parse[0] != ';')
+               return false;
+       parse++;
+
+       /* Skip first field "filename"; don't know what to do with it. */
+       free(next_hex_encoded_field(&parse, ';'));
+
+       char *cmdline = next_hex_encoded_field(&parse, ';');
+       char *arg;
+       while (cmdline != NULL && (arg = next_hex_encoded_field(&parse, ';')) != NULL) {
+               char *new_cmdline = alloc_printf("%s %s", cmdline, arg);
+               free(cmdline);
+               free(arg);
+               cmdline = new_cmdline;
+       }
+
+       if (cmdline != NULL) {
+               if (target->semihosting != NULL) {
+                       LOG_INFO("GDB set inferior command line to '%s'", cmdline);
+                       free(target->semihosting->cmdline);
+                       target->semihosting->cmdline = cmdline;
+               } else {
+                       LOG_INFO("GDB set inferior command line to '%s' but semihosting is unavailable", cmdline);
+                       free(cmdline);
+               }
+       }
+
+       gdb_restart_inferior(connection, packet, packet_size);
+       gdb_put_packet(connection, "S00", 3);
+       return true;
+}
+
 static int gdb_v_packet(struct connection *connection,
                char const *packet, int packet_size)
 {
@@ -2908,6 +2999,16 @@ static int gdb_v_packet(struct connection *connection,
                return ERROR_OK;
        }
 
+       if (strncmp(packet, "vRun", 4) == 0) {
+               bool handled;
+
+               handled = gdb_handle_vrun_packet(connection, packet, packet_size);
+               if (!handled)
+                       gdb_put_packet(connection, "", 0);
+
+               return ERROR_OK;
+       }
+
        /* if flash programming disabled - send a empty reply */
 
        if (gdb_flash_program == 0) {
@@ -3300,14 +3401,7 @@ static int gdb_input_inner(struct connection *connection)
                                        break;
                                case 'R':
                                        /* handle extended restart packet */
-                                       breakpoint_clear_target(target);
-                                       watchpoint_clear_target(target);
-                                       command_run_linef(connection->cmd_ctx, "ocd_gdb_restart %s",
-                                                       target_name(target));
-                                       /* set connection as attached after reset */
-                                       gdb_con->attached = true;
-                                       /*  info rtos parts */
-                                       gdb_thread_packet(connection, packet, packet_size);
+                                       gdb_restart_inferior(connection, packet, packet_size);
                                        break;
 
                                case 'j':