vfs - kinda good vfs implementation

kernel/src/dbg/sym.c

@@ -0,0 +1,56 @@
+#include "dbg/sym.h"
+#include "exec/elf.h"
+#include "limine.h"
+#include "sys/errhnd/panic.h"
+#include "sys/log.h"
+#include <lib/string.h>
+#include <mm/liballoc/liballoc.h>
+
+static Elf64_Sym *__ksym_symtab;
+static char *__ksym_strtab;
+static int __ksym_symcount = 0;
+
+__attribute__((used, section(".limine_requests"))) static volatile struct
+    limine_executable_file_request exec_file_rq = {
+        .id = LIMINE_EXECUTABLE_FILE_REQUEST, .revision = 3};
+
+void ksym_init() {
+  char *img = exec_file_rq.response->executable_file->address;
+  Elf64_Ehdr *ehdr = (Elf64_Ehdr *)img;
+  if (ehdr->e_ident[EI_MAG0] != ELFMAG0 || ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
+      ehdr->e_ident[EI_MAG2] != ELFMAG2 || ehdr->e_ident[EI_MAG3] != ELFMAG3) {
+    panic("kernel - how did i even boot? *starts galaxy brain meme*");
+  }
+
+  Elf64_Shdr *shdr = (Elf64_Shdr *)(img + ehdr->e_shoff);
+  const char *shstrtab = (char *)img + shdr[ehdr->e_shstrndx].sh_offset;
+
+  for (int j = 0; j < ehdr->e_shnum; j++) {
+    if (shdr[j].sh_type == SHT_SYMTAB) {
+      __ksym_symtab = (Elf64_Sym *)(img + shdr[j].sh_offset);
+      __ksym_symcount = shdr[j].sh_size / shdr[j].sh_entsize;
+    } else if (shdr[j].sh_type == SHT_STRTAB &&
+               strcmp(shstrtab + shdr[j].sh_name, ".strtab") == 0) {
+      __ksym_strtab = (char *)(img + shdr[j].sh_offset);
+    }
+  }
+
+  log("kernel - loaded %d symbols\n", __ksym_symcount);
+}
+
+func *ksym_fromip(uint64_t ip) {
+  for (int i = 0; i < __ksym_symcount; i++) {
+    uint64_t value = __ksym_symtab[i].st_value;
+    uint64_t size = __ksym_symtab[i].st_size;
+
+    if (value <= ip && ip < (value + size)) {
+      func *f = malloc(sizeof(func));
+      f->base = value;
+      f->ip = ip;
+      f->name = (__ksym_strtab + __ksym_symtab[i].st_name);
+      return f;
+    }
+  }
+
+  return NULL;
+}