feat(xce-test-e2e-primitives): add echo command (task 1.2)

.kiro/specs/xce-test-e2e-primitives/tasks.md

@@ -9,7 +9,7 @@
   - Observable: a piped script with a bogus/failing command makes `xce_test` exit non-zero; an all-valid script exits 0; with `set continue-on-error` a failing line does not stop later lines but the final exit is still non-zero; `#`/blank lines are ignored.
   - _Requirements: 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 6.1, 6.2_
   - _Boundary: VerdictLoopWrapper_
-- [ ] 1.2 `echo` command
+- [x] 1.2 `echo` command
   - Add `cmd_echo` (table-registered) that prints its argument message and returns success.
   - Observable: `echo hello` emits `hello` and the command succeeds (exit unaffected).
   - _Requirements: 6.3_

src/controller/testsuite/test.c

@@ -115,6 +115,7 @@ extern int cmd_qctrl(int, char*[]);
 extern int cmd_runtasks(int, char*[]);
 extern int cmd_setpend(int, char*[]);
 extern int cmd_jobinfo(int, char*[]);
+extern int cmd_echo(int, char*[]);
 static int worker_house_keeping(void*);
 
 /* Session verdict / loop state (xce-test-e2e-primitives task 1.1).
@@ -151,6 +152,7 @@ static command_t top_commands[] = {
     { "scheduler", cmd_scheduler,    "In scheduler context" },
     { "client",    cmd_client,       "In client context"    },
     { "set",       cmd_set,          "Show/Set settings"    },
+    { "echo",      cmd_echo,         "Print a message"      },
     { "quit",      cmd_quit,         "Quit xce test"        },
     { (char*)NULL, (cmd_func_t)NULL, (char*)NULL            }
 };
@@ -167,6 +169,7 @@ static command_t worker_commands[] = {
     { "join",      cmd_join_worker,  "Join the cluster"          },
     { "jfinish",   cmd_jobfinish,    "tell controller jobfinish" },
     { "resupdate", cmd_resupdate,    "update res vals"           },
+    { "echo",      cmd_echo,         "Print a message"           },
     { (char*)NULL, (cmd_func_t)NULL, (char*)NULL                 }
 };
 
@@ -191,6 +194,7 @@ static command_t client_commands[] = {
     { "resval",     cmd_resval,       "get value of res"            },
     { "taskrun",    cmd_runtasks,     "run tasks"                   },
     { "help",       cmd_help,         "Display this text"           },
+    { "echo",       cmd_echo,         "Print a message"             },
     { "quit",       cmd_quit,         "Quit xce test"               },
     { (char*)NULL,  (cmd_func_t)NULL, (char*)NULL                   }
 };
@@ -207,6 +211,7 @@ static command_t scheduler_commands[] = {
     { "join",      cmd_join_sched,   "Join the cluster"    },
     { "getconf",   cmd_getconf,      "Get conf of cluster" },
     { "setpend",   cmd_setpend,      "set job pend reason" },
+    { "echo",      cmd_echo,         "Print a message"     },
     { (char*)NULL, (cmd_func_t)NULL, (char*)NULL           }
 };
 
@@ -473,6 +478,25 @@ int cmd_help(int argc, char* argv[])
     return rc;
 }
 
+/* echo <message...> — print the remainder of the line (argv[1..] joined by
+ * single spaces) followed by a newline and succeed (xce-test-e2e-primitives
+ * task 1.2, Req 6.3). `echo` with no argument prints an empty line and still
+ * succeeds. Returns 0 always so it never marks the session failed. */
+int cmd_echo(int argc, char* argv[])
+{
+    int i;
+
+    for (i = 1; i < argc; i++) {
+        if (i > 1) {
+            putchar(' ');
+        }
+        fputs(argv[i], stdout);
+    }
+    putchar('\n');
+
+    return 0;
+}
+
 int cmd_up(int argc, char* argv[])
 {
     if (active_ctx->parent != NULL) {