check if we have initfs instead of assuming first module exists and is initfs

disk/limine/limine.conf

@@ -2,6 +2,7 @@ timeout: 0
 quiet:   yes
 
 /Calcite
-protocol:    limine
+protocol:       limine
-path:        boot():/calcite/kernel.elf
+path:           boot():/calcite/kernel.elf
-module_path: boot():/calcite/initfs.tar
+module_path:    boot():/calcite/initfs.tar
+module_cmdline: initfs

kernel/include/utility.h

@@ -0,0 +1,21 @@
+/* Calcite, kernel/include/utility.h
+ * Copyright 2025 Benji Dial
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+//returns 1 if equal, 0 if not.
+int strequ(const char *str1, const char *str2);

kernel/src/entry.c

@@ -15,6 +15,7 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 
+#include <utility.h>
 #include <initfs.h>
 #include <limine.h>
 #include <paging.h>
@@ -100,7 +101,18 @@ static uint64_t initfs_length;
       fb->blue_mask_shift != 0 || fb->blue_mask_size != 8)
     die();
 
-  struct limine_file *initfs = module_request.response->modules[0];
+  //find the initfs, and die if we don't have one.
+
+  struct limine_file *initfs = 0;
+  struct limine_module_response *response = module_request.response;
+  for (uint64_t i = 0; i < response->module_count; ++i)
+    if (strequ(response->modules[i]->cmdline, "initfs")) {
+      initfs = response->modules[i];
+      break;
+    }
+
+  if (!initfs)
+    die();
 
   //set up page tables. we will mark the regions with bootloader structures as
   //usable, so we need to be careful not to allocate any physical pages until

kernel/src/utility.c

@@ -0,0 +1,29 @@
+/* Calcite, kernel/src/utility.c
+ * Copyright 2025 Benji Dial
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <utility.h>
+
+int strequ(const char *str1, const char *str2) {
+  while (1) {
+    if (!*str1 && !*str2)
+      return 1;
+    if (*str1 != *str2)
+      return 0;
+    ++str1;
+    ++str2;
+  }
+}