feat: extend kmain with execReaperThread and consoleInjectorThread

src/kmain.c

@@ -307,13 +307,203 @@ static uint32 spawnUser(const char* path, const char* name, uint64 stackTop, uin
         return threadInvalidId;
     }
 
-    pagingMapUserRange(stackTop - userStackSize, userStackSize);
+    pagingMapUserRangeFlags(stackTop - userStackSize, userStackSize, pageNoExecute);
-    uint32 pid = threadCreateUser(name, entry, stackTop);
+
+    /* Every boot-launched program gets a real, if minimal, argv: just its
+       own path, matching what a real OS would put in argv[0]. Nothing in
+       this kernel's boot sequence needs more than that -- programs wanting
+       specific arguments are spawned at runtime instead (doSpawn,
+       syscall.c), where the caller controls argv directly. */
+    const char* argv[1] = { path };
+    uint64 initialRsp;
+    if (!elfBuildInitialStack(stackTop, userStackSize, argv, 1, &initialRsp)) {
+        kprintf("[user] '%s' not started: argv did not fit its stack\n", path);
+        return threadInvalidId;
+    }
+
+    uint32 pid = threadCreateUser(name, entry, initialRsp);
+    if (pid == threadInvalidId) {
+        kprintf("[user] '%s' not started: thread table full\n", path);
+        return threadInvalidId;
+    }
     if (brkStart)
         threadSetBrk(pid, brkStart);
 
     kprintf("[user] loaded '%s' pid=%u entry=%p stackTop=%p (%lu bytes)\n",
             name, pid, (void*)entry, (void*)stackTop, size);
+    return pid;
+}
+
+/* proctest.c's very last action on its success path is userExec(), which
+   replaces its own image with exectarget.c's -- so the only way to observe
+   from OUTSIDE that process that exec() genuinely happened (rather than
+   proctest simply exiting cleanly on its own) is to threadJoin() the exact
+   pid kmain.c originally gave proctest and check that its eventual exit
+   code is exectarget's (7), not proctest's own success path (which never
+   returns 7 -- it either exits 1 on a self-detected FAIL or never exits at
+   all once exec succeeds). A mismatch or an exit code belonging to neither
+   program both surface as a plain FAIL below. */
+#define execDemoExitCode 7ull
+
+static uint32 execDemoPid = threadInvalidId;
+
+static void execReaperThread(void)
+{
+    if (execDemoPid == threadInvalidId) {
+        kprintf("[user] exec demo skipped: proctest never started\n");
+        for (;;)
+            halt();
+    }
+
+    int64 code = threadJoin(execDemoPid);
+    bool ok = (code == (int64)execDemoExitCode);
+    kprintf("[user] exec demo: pid=%u final exitCode=%ld (expected %lu) -> %s\n",
+            execDemoPid, code, execDemoExitCode, ok ? "exec-pid-preserved-ok" : "exec-pid-preserved-FAIL");
+
+    for (;;)
+        halt();
+}
+
+/* Headless QEMU has no automated way to drive a real PS/2 keyboard device --
+   ci-test.sh only captures the COM1 serial log, and scripts no QEMU monitor
+   "sendkey" command -- so this thread simulates exactly one keystroke the
+   same way a real IRQ1 handler would: by calling keyboardHandleScancode
+   (keyboard.h) directly with the scancode a real 'k' keypress generates.
+   consolereader1.c and consolereader2.c are both already parked in a real,
+   blocking userRead(0, ...) well before this fires (the sleep below gives
+   every boot-time thread, including both of them, at least one CFS-lite
+   timeslice first) -- keyboard.c's per-reader fan-out then delivers each of
+   them its own independent copy of the same byte, proving two entirely
+   unrelated ring-3 processes can share "the keyboard" without racing each
+   other for it, the gap the previous wave's own notes called out as the
+   next logical step after pipes. */
+#define consoleDemoScancodeK 0x25
+#define consoleInjectDelayMs 250
+
+static void consoleInjectorThread(void)
+{
+    threadSleep(consoleInjectDelayMs);
+    while (currentThread()->state == threadSleeping)
+        halt();
+
+    kprintf("[kbd]  injecting synthetic keypress 'k' for the console fan-out demo\n");
+    keyboardHandleScancode(consoleDemoScancodeK);
+
+    for (;;)
+        halt();
+}
+
+/* Same "headless QEMU cannot drive a real PS/2 device" reasoning as
+   consoleInjectorThread above, this time simulating a real Ctrl-C
+   keypress (left-Ctrl held, 'c' pressed and released, left-Ctrl released)
+   by calling keyboardHandleScancode with exactly the four scancodes a
+   physical keyboard would generate for it -- the live ring-3 proof that
+   sched.h's new Thread.pgid and keyboard.c's own new INTR interception
+   actually scope a terminal-generated signal to ONE process group
+   (pgroupfg.c, made the foreground below) and leave a completely
+   different one (pgroupbg.c, deliberately left as its own default group)
+   untouched. pgroupfgPid/pgroupbgPid are threadInvalidId if either
+   program failed to load (thread table full, missing from the ramdisk) --
+   this thread degrades to a silent no-op rather than acting on a bogus id,
+   the same "skipped" pattern execReaperThread already uses for its own
+   demo. */
+#define scancodeLeftCtrlMake  0x1D
+#define scancodeLeftCtrlBreak 0x9D
+#define scancodeCPressMake    0x2E
+#define scancodeCPressBreak   0xAE
+#define pgroupInjectDelayMs 400
+#define pgroupSettleDelayMs 100
+
+static uint32 pgroupfgPid = threadInvalidId;
+static uint32 pgroupbgPid = threadInvalidId;
+
+static void pgroupInjectorThread(void)
+{
+    if (pgroupfgPid == threadInvalidId || pgroupbgPid == threadInvalidId) {
+        kprintf("[kbd]  process-group demo skipped: pgroupfg/pgroupbg never started\n");
+        for (;;)
+            halt();
+    }
+
+    threadSleep(pgroupInjectDelayMs);
+    while (currentThread()->state == threadSleeping)
+        halt();
+
+    kprintf("[kbd]  injecting synthetic ctrl-c for the process-group demo\n");
+    keyboardHandleScancode(scancodeLeftCtrlMake);
+    keyboardHandleScancode(scancodeCPressMake);
+    keyboardHandleScancode(scancodeCPressBreak);
+    keyboardHandleScancode(scancodeLeftCtrlBreak);
+
+    /* Give the scheduler a real timeslice to actually deliver the
+       resulting sigInt to pgroupfg (early-wake + return-to-ring3, not
+       instantaneous) before this thread moves on to check anything. */
+    threadSleep(pgroupSettleDelayMs);
+    while (currentThread()->state == threadSleeping)
+        halt();
+
+    int64 fgCode = threadJoin(pgroupfgPid);
+    bool fgOk = (fgCode == (int64)(128 + sigInt));
+    kprintf("[user] pgroup demo: fg pid=%u final exitCode=%ld (expected 128+sigInt=%d) -> %s\n",
+            pgroupfgPid, fgCode, 128 + sigInt, fgOk ? "pgrouptest-fg-terminated-by-sigint-ok" : "FAIL");
+
+    /* Proves pgroupbg (a DIFFERENT process group, never named as
+       foreground) is still genuinely alive and running real code after
+       the Ctrl-C above -- if keyboard.c's group scoping were ever broken
+       to reach it too, pgroupbg would already be Dead by now and this
+       sigRaise (signal.h) would silently do nothing, so pgroupbg.c's own
+       "still-alive-after-ctrlc-ok" needle would simply never appear in
+       the boot log, failing the gate. */
+    sigRaise(pgroupbgPid, sigUsr1);
+
+    for (;;)
+        halt();
+}
+
+/*
+ * The live ring-3 proof for shell.c's new `NAME [ARGS] [&]` job control
+ * (jobctl.h does the actual spawning/terminal-ownership work): rather than
+ * spawning jobctlfg.c/jobctlbg.c directly the way every demo above does,
+ * this thread TYPES commands at the real interactive shell (shellRun,
+ * already running as its own boot-time thread) through the same
+ * injected-keystroke mechanism consoleInjectorThread/pgroupInjectorThread
+ * above already use for the same "no automated way to drive a real PS/2
+ * device under headless QEMU" reason -- proving the shell's own runtime
+ * decision of what to load and whether to grant it the terminal, not just
+ * that jobctl.c's functions work when called directly.
+ *
+ * Scancode values below are read straight off keyboard.c's own
+ * scancodeLower table (index N there is scancode N here -- already cross-
+ * checked against that file's own worked examples: index 0x25 is 'k',
+ * exactly consoleDemoScancodeK above; index 0x2E is 'c', exactly
+ * scancodeCPressMake above), not guessed.
+ */
+#define scancodeMakeJ          0x24
+#define scancodeMakeO          0x18
+#define scancodeMakeB          0x30
+#define scancodeMakeT          0x14
+#define scancodeMakeL          0x26
+#define scancodeMakeG          0x22
+#define scancodeMakeF          0x21
+#define scancodeMakeSpace      0x39
+#define scancodeMakeSeven      0x08
+#define scancodeMakeEnter      0x1C
+#define scancodeLeftShiftMake  0x2A
+#define scancodeLeftShiftBreak 0xAA
+#define scancodeBreakBit       0x80
+
+/* Additional letters/symbol needed only by pipelineDriverThread's own
+   "pipesrc | pipesink" command below -- same cross-checked-against-
+   scancodeLower sourcing as the block above (index 0x19 is 'p', 0x17 is
+   'i', 0x12 is 'e', 0x1F is 's', 0x13 is 'r', 0x31 is 'n', 0x25 is 'k'
+   (equal to consoleDemoScancodeK above, kept as this file's own named copy
+   for this demo, the same "each caller of this pattern owns its own named
+   copy" choice jobctl.c/kmain.c/syscall.c already make elsewhere), 0x2B is
+   '\\', shifted into '|' by scancodeUpper the same way scancodeMakeSeven
+   is shifted into '&' above). */
+#define scancodeMakeP          0x19
+#define scancodeMakeI          0x17
+#define scancodeMakeE          0x12
 }
 
 void kmain(uint32 magic, uint64 multibootInfo)