libinput Generic way of gathering user commandline input

ce/interp.c

@@ -340,26 +340,15 @@ static void help (struct context* context) {
   cprintf (context, "quit\n");
 }
 
-static void cmd_cancel_proc (void* arg) {
-  int pid = (int)(uintptr_t)arg;
-
-  uint8_t ch = 0;
-  for (;;) {
-    if (stream_read (process_get_pgid (), STREAM_IN, &ch, 1) > 0 && ch == KB_CTRL ('C'))
-      break;
-    else
-      sched ();
-  }
-
-  kill (pid);
-}
+struct cmd_write_proc_ctx {
+  int pgid;
+  int cancel_pid;
+};
 
 static void cmd_collect_proc (void* arg) {
-#define RECV_MAX (1024 * 16)
-
   int pgid = (int)(uintptr_t)arg;
 
-  char recv[RECV_MAX];
+  char recv[1024];
   int n;
   for (;;) {
     if ((n = stream_read (pgid, STREAM_OUT, (void*)recv, sizeof (recv) - 1)) > 0)
@@ -369,6 +358,24 @@ static void cmd_collect_proc (void* arg) {
   }
 }
 
+static void cmd_write_proc (void* arg) {
+  struct cmd_write_proc_ctx* ctx = arg;
+
+  uint8_t ch = 0;
+  for (;;) {
+    if (stream_read (process_get_pgid (), STREAM_IN, &ch, 1) > 0) {
+      if (ch == KB_CTRL ('C')) {
+        kill (ctx->cancel_pid);
+        return;
+      }
+
+      stream_write (ctx->pgid, STREAM_IN, &ch, 1);
+    } else {
+      sched ();
+    }
+  }
+}
+
 static void execute_cmd (struct ast_cmd* cmd, struct context* context) {
   if (strcmp (cmd->name, "echo") == 0) {
     echo (context, cmd->args, cmd->arg_count);
@@ -442,16 +449,18 @@ static void execute_cmd (struct ast_cmd* cmd, struct context* context) {
       }
     }
 
+    struct cmd_write_proc_ctx wpctx = {.pgid = pgid, .cancel_pid = pid};
+
+    struct process_data* write_pdata = process_spawn (&cmd_write_proc, (void*)&wpctx);
     struct process_data* collect_pdata = process_spawn (&cmd_collect_proc, (void*)(uintptr_t)pgid);
-    struct process_data* cancel_pdata = process_spawn (&cmd_cancel_proc, (void*)(uintptr_t)pid);
 
     exec_partial_fini (pid);
     wait_for_pid (pid);
 
+    kill (write_pdata->pid);
+    process_data_free (write_pdata);
     kill (collect_pdata->pid);
     process_data_free (collect_pdata);
-    kill (cancel_pdata->pid);
-    process_data_free (cancel_pdata);
   }
 }