rtos: Rewrite rtos_create() for readability

The new code is almost functionally equivalent to the old; besides
error handling the only difference is that the code is now readable.

Many thanks to Matthias Blaicher for pointing out an iteration error
in the rtos_try_next() change, which also affected this change.

Change-Id: If38b87439e9de2303b220b3a7e3200ceaa8391da
Signed-off-by: Peter Stuge <peter@stuge.se>
Reviewed-on: http://openocd.zylin.com/893
Tested-by: jenkins
Reviewed-by: Matthias Blaicher <matthias@blaicher.com>

diff --git a/src/rtos/rtos.c b/src/rtos/rtos.c
index 524e1dacac39c4d2809581a9e6fbd17eae68133d..e0160839bbc4cc93566c73c97735b395fbe81a02 100644 (file)
--- a/src/rtos/rtos.c
+++ b/src/rtos/rtos.c
@@ -52,78 +52,87 @@ int rtos_smp_init(struct target *target)
        return ERROR_TARGET_INIT_FAILED;
 }
 
+static int os_alloc(struct target *target, struct rtos_type *ostype)
+{
+       struct rtos *os = target->rtos = calloc(1, sizeof(struct rtos));
+
+       if (!os)
+               return JIM_ERR;
+
+       os->type = ostype;
+       os->current_threadid = -1;
+       os->current_thread = 0;
+       os->symbols = NULL;
+       os->target = target;
+
+       /* RTOS drivers can override the packet handler in _create(). */
+       os->gdb_thread_packet = rtos_thread_packet;
+
+       return JIM_OK;
+}
+
+static void os_free(struct target *target)
+{
+       if (!target->rtos)
+               return;
+
+       if (target->rtos->symbols)
+               free(target->rtos->symbols);
+
+       free(target->rtos);
+       target->rtos = NULL;
+}
+
+static int os_alloc_create(struct target *target, struct rtos_type *ostype)
+{
+       int ret = os_alloc(target, ostype);
+
+       if (JIM_OK == ret) {
+               ret = target->rtos->type->create(target);
+               if (ret != JIM_OK)
+                       os_free(target);
+       }
+
+       return ret;
+}
+
 int rtos_create(Jim_GetOptInfo *goi, struct target *target)
 {
        int x;
        char *cp;
-       if (!goi->isconfigure) {
-               if (goi->argc != 0) {
-                       if (goi->argc != 0) {
-                               Jim_WrongNumArgs(goi->interp,
-                                       goi->argc, goi->argv,
-                                       "NO PARAMS");
-                               return JIM_ERR;
-                       }
+       struct Jim_Obj *res;
 
-                       Jim_SetResultString(goi->interp,
-                               target_type_name(target), -1);
-               }
+       if (!goi->isconfigure && goi->argc != 0) {
+               Jim_WrongNumArgs(goi->interp, goi->argc, goi->argv, "NO PARAMS");
+               return JIM_ERR;
        }
 
-       if (target->rtos)
-               free((void *)(target->rtos));
-                                               /*                      e = Jim_GetOpt_String(goi,
-                                                * &cp, NULL); */
-/*                     target->rtos = strdup(cp); */
+       os_free(target);
 
        Jim_GetOpt_String(goi, &cp, NULL);
-       /* now does target type exist */
 
        if (0 == strcmp(cp, "auto")) {
-               /* auto detection of RTOS */
+               /* Auto detect tries to look up all symbols for each RTOS,
+                * and runs the RTOS driver's _detect() function when GDB
+                * finds all symbols for any RTOS. See rtos_qsymbol(). */
                target->rtos_auto_detect = true;
-               x = 0;
-       } else {
 
-               for (x = 0; rtos_types[x]; x++) {
-                       if (0 == strcmp(cp, rtos_types[x]->name)) {
-                               /* found */
-                               break;
-                       }
-               }
-               if (rtos_types[x] == NULL) {
-                       Jim_SetResultFormatted(goi->interp, "Unknown rtos type %s, try one of ",
-                               cp);
-                       for (x = 0; rtos_types[x]; x++) {
-                               if (rtos_types[x + 1]) {
-                                       Jim_AppendStrings(goi->interp,
-                                               Jim_GetResult(goi->interp),
-                                               rtos_types[x]->name,
-                                               ", ", NULL);
-                               } else {
-                                       Jim_AppendStrings(goi->interp,
-                                               Jim_GetResult(goi->interp),
-                                               " or ",
-                                               rtos_types[x]->name, NULL);
-                               }
-                       }
-                       return JIM_ERR;
-               }
+               /* rtos_qsymbol() will iterate over all RTOSes. Allocate
+                * target->rtos here, and set it to the first RTOS type. */
+               return os_alloc(target, rtos_types[0]);
        }
-       /* Create it */
-       target->rtos = calloc(1, sizeof(struct rtos));
-       target->rtos->type = rtos_types[x];
-       target->rtos->current_threadid = -1;
-       target->rtos->current_thread = 0;
-       target->rtos->symbols = NULL;
-       target->rtos->target = target;
-       /* put default thread handler in linux usecase it is overloaded*/
-       target->rtos->gdb_thread_packet = rtos_thread_packet;
-
-       if (0 != strcmp(cp, "auto"))
-               target->rtos->type->create(target);
 
-       return JIM_OK;
+       for (x = 0; rtos_types[x]; x++)
+               if (0 == strcmp(cp, rtos_types[x]->name))
+                       return os_alloc_create(target, rtos_types[x]);
+
+       Jim_SetResultFormatted(goi->interp, "Unknown RTOS type %s, try one of: ", cp);
+       res = Jim_GetResult(goi->interp);
+       for (x = 0; rtos_types[x]; x++)
+               Jim_AppendStrings(goi->interp, res, rtos_types[x]->name, ", ", NULL);
+       Jim_AppendStrings(goi->interp, res, " or auto", NULL);
+
+       return JIM_ERR;
 }
 
 int gdb_thread_packet(struct connection *connection, char *packet, int packet_size)