ld: implement an actual program loader

sys/ld/resolve.c

@@ -0,0 +1,22 @@
+#include "elf.h"
+
+#include <mango/log.h>
+#include <stdint.h>
+#include <stdio.h>
+
+uintptr_t dl_runtime_resolve(struct elf_image *img, unsigned long sym_id)
+{
+	elf_sym_t *sym
+		= (elf_sym_t *)((virt_addr_t)img->e_base + img->e_dynsym);
+	const char *sym_name = (const char *)img->e_base + img->e_strtab
+	                     + sym[sym_id + 1].st_name;
+	// kern_logf("%s: request for symbol %s", img->e_leaf.l_name, sym_name);
+	virt_addr_t sym_addr = elf_image_find_linked_symbol(img, sym_name);
+	virt_addr_t *sym_slot
+		= (virt_addr_t *)((virt_addr_t)img->e_base + img->e_got_plt
+	                          + ((sym_id + 3) * sizeof(virt_addr_t)));
+	// kern_logf("symbol %s = %zx", sym_name, sym_addr);
+	// kern_logf("slot %s = %zx", sym_name, sym_slot);
+	*sym_slot = sym_addr;
+	return sym_addr;
+}