Parse multiboot information

src/kernel/boot/multiboot.tt

@@ -0,0 +1,144 @@
+// vim: ft=c
+#include <ttest.h>
+
+#include <debug.h>
+#include <memory.h>
+#undef debug
+#define debug(...)
+#undef P2V
+#define P2V(addr) (void *)((uintptr_t)(addr))
+#include "multiboot.c"
+
+#include <string.h>
+#include <stdarg.h>
+
+#define MAGIC 0x36D76289
+
+struct mboot2_tag *generate_tag(uint32_t type, void *data, uint32_t data_size)
+{
+  struct mboot2_tag *tag = calloc(1, sizeof(struct mboot2_tag) + data_size);
+  tag->type = type;
+  tag->size = sizeof(struct mboot2_tag) + data_size;
+  if(data_size)
+    memcpy(tag->data, data, data_size);
+  return tag;
+}
+
+#define padded_size(tag) (tag->size + ((tag->size%8)?(8-(tag->size%8)):0))
+
+struct mboot2_taglist *generate_taglist(int num, ...)
+{
+  va_list args;
+  va_start(args, num);
+  uint32_t total_size = sizeof(struct mboot2_taglist);
+  struct mboot2_tag **tags = calloc(num, sizeof(struct mboot2_tag *));
+  for(int i = 0; i < num; i++)
+  {
+    tags[i] = va_arg(args, struct mboot2_tag *);
+    total_size += padded_size(tags[i]);
+  }
+
+  struct mboot2_taglist *taglist = calloc(1, total_size);
+  taglist->total_size = total_size;
+
+  int pos = 8;
+  uint8_t *p = (uint8_t *)taglist;
+  for(int i = 0; i < num; i++)
+  {
+    memcpy(&p[pos], tags[i], tags[i]->size);
+    pos += padded_size(tags[i]);
+    free(tags[i]);
+  }
+  va_end(args);
+
+  return taglist;
+}
+
+TEST(correctly_identifies_multiboot2_magic)
+{
+  uint32_t tags[] = {16, 0, 0, 8};
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_INT(kernel_boot_data.multiboot_version, 2);
+}
+
+TEST(reads_boot_loader_name)
+{
+  char *name = "ttest";
+  struct mboot2_taglist *tags = generate_taglist(2,
+    generate_tag(2, name, strlen(name) + 1),
+    generate_tag(0,0,0));
+
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_STR(kernel_boot_data.bootloader, name, strlen(name));
+  free(tags);
+}
+TEST(reads_kernel_commandline)
+{
+  char *cmd = "mittos64-kern boot";
+  struct mboot2_taglist *tags = generate_taglist(2,
+    generate_tag(1, cmd, strlen(cmd) + 1),
+    generate_tag(0,0,0));
+
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_STR(kernel_boot_data.commandline, cmd, strlen(cmd));
+  free(tags);
+}
+// Here are four very simmilar tests
+// The difference is what values are checked and the order of the tags
+// Their existence is based on experience - helped me actually find a bug
+TEST(reads_multiple_tags_1)
+{
+  char *cmd = "mittos64-kern boot";
+  char *name = "ttest";
+  struct mboot2_taglist *tags = generate_taglist(3,
+    generate_tag(1, cmd, strlen(cmd) + 1),
+    generate_tag(2, name, strlen(name) + 1),
+    generate_tag(0,0,0)
+  );
+
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_STR(kernel_boot_data.commandline, cmd, strlen(cmd));
+  free(tags);
+}
+TEST(reads_multiple_tags_2)
+{
+  char *cmd = "mittos64-kern boot";
+  char *name = "ttest";
+  struct mboot2_taglist *tags = generate_taglist(3,
+    generate_tag(1, cmd, strlen(cmd) + 1),
+    generate_tag(2, name, strlen(name) + 1),
+    generate_tag(0,0,0)
+  );
+
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_STR(kernel_boot_data.bootloader, name, strlen(name));
+  free(tags);
+}
+TEST(reads_multiple_tags_3)
+{
+  char *cmd = "mittos64-kern boot";
+  char *name = "ttest";
+  struct mboot2_taglist *tags = generate_taglist(3,
+    generate_tag(2, name, strlen(name) + 1),
+    generate_tag(1, cmd, strlen(cmd) + 1),
+    generate_tag(0,0,0)
+  );
+
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_STR(kernel_boot_data.commandline, cmd, strlen(cmd));
+  free(tags);
+}
+TEST(reads_multiple_tags_4)
+{
+  char *cmd = "mittos64-kern boot";
+  char *name = "ttest";
+  struct mboot2_taglist *tags = generate_taglist(3,
+    generate_tag(2, name, strlen(name) + 1),
+    generate_tag(1, cmd, strlen(cmd) + 1),
+    generate_tag(0,0,0)
+  );
+
+  parse_multiboot(MAGIC, tags);
+  ASSERT_EQ_STR(kernel_boot_data.bootloader, name, strlen(name));
+  free(tags);
+}