From d1ff7bcc91886626dc9060ec5fb67ee102ab7c1d Mon Sep 17 00:00:00 2001
From: Jon Santmyer <jon@jonsantmyer.com>
Date: Mon, 11 Mar 2024 21:30:31 -0400
Subject: usermode capable kernel with logging syscall

---
 ird/initrd.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 ird/initrd.c

(limited to 'ird/initrd.c')

diff --git a/ird/initrd.c b/ird/initrd.c
new file mode 100644
index 0000000..f219243
--- /dev/null
+++ b/ird/initrd.c
@@ -0,0 +1,88 @@
+#include "initrd.h"
+#include "lib/string.h"
+#include "io/log.h"
+#include "boot/boot.h"
+#include "boot/cmdline.h"
+#include "mem/memory.h"
+
+struct SlabCache s_initrd_cache;
+struct SLinkedList s_initrd_files;
+
+static size_t
+s_tar_oct_dec(const char *oct)
+{
+    size_t value = 0;
+    while(*oct != 0) {
+        value *= 8;
+        value += (*oct) - '0';
+        oct++;
+    }
+    return value;
+}
+
+static void
+s_initrd_parse(struct BootModule *module)
+{
+    struct TARSector *sector = (struct TARSector*)module->addr;
+    while(true) {
+        struct TARHeader *header = (struct TARHeader*)sector;
+        if(header->name[0] == 0) break;
+
+        struct InitrdFile *file = mem_slab_alloc(&s_initrd_cache);
+        *file = (struct InitrdFile){ 
+            .header = header,
+            .name = header->name,
+            .size = s_tar_oct_dec(header->size),
+            .data = &sector[1]
+        };
+        klogf("File %s size %i\n", file->name, file->size);
+        sll_push(&s_initrd_files, file);
+ 
+        sector = &sector[(file->size / 512) + 1];
+        if(file->size % 512 > 0) sector = &sector[1];
+    }
+}
+
+struct InitrdFile *
+ird_getfile(const char *path)
+{
+    for(struct SLLNode *node = s_initrd_files.head; node != NULL; node = node->next) {
+        struct InitrdFile *file = (struct InitrdFile*)node;
+        if(strcmp(file->name, path) == 0) return file;
+    }
+    return NULL;
+}
+
+struct SLinkedList *
+ird_getfiles(void)
+{
+    return &s_initrd_files;
+}
+
+void
+initrd_setup(void)
+{
+    const char *initrd_path = cmdline_get("initrd");
+    if(initrd_path == 0) {
+        klogf("No initrd loaded!\n");
+        return;
+    }
+    klogf("Initrd located in module path %s\n", initrd_path);
+    struct BootModule *initrd_module = NULL;
+    for(size_t i = 0; i < boot_module_count; i++) {
+        struct BootModule *module = &boot_modules[i];
+        if(strcmp(module->path, initrd_path) == 0) {
+            initrd_module = module;
+            break;
+        }
+    }
+
+    if(initrd_module == NULL) {
+        klogf("Initrd not found in modules!\n");
+        return;
+    }
+
+    sll_new(&s_initrd_files, sizeof(struct InitrdFile));
+    mem_slabcache_new(&s_initrd_cache, "initrd files", sizeof(struct InitrdFile));
+    s_initrd_parse(initrd_module);
+}
-- 
cgit v1.2.1