1 files changed, 76 insertions, 35 deletions

diff --git a/src/kernel/idt.c b/src/kernel/idt.c
index 8de5448..61966e0 100644
--- a/src/kernel/idt.c
+++ b/src/kernel/idt.c
@@ -34,60 +34,95 @@ struct {
   .start = (uint32_t)idt
 };
 
-//file handles as (drive_number << 8) + file_id_t
+bool verify_file_handle(uint32_t handle, struct drive **d, uint32_t *f) {
+  *d = drives + (handle >> 24);
+  *f = handle & 0x00ffffff;
 
-uint32_t sc_open_file(uint32_t drive_number, char *path) {
-  return (drive_number << 8) + drives[drive_number].get_file(drives + drive_number, path);
+  if (!*f || (*d >= drives + n_drives)) {
+    logf(LOG_WARN, "syscall with file handle 0x%h", handle);
+    return false;
+  }
+  else
+    return true;
+}
+
+uint32_t sc_open_file(const char *path) {
+  struct drive *did;
+  const char *sub;
+  map_path(path, &did, &sub);
+  if (!did)
+    return 0;
+
+  const file_id_t fid = did->get_file(did, sub);
+  return fid ? ((did - drives) << 24) + fid : 0;
 }
 
 void sc_close_file(uint32_t handle) {
-  if (!handle)
-    return;
-  drives[handle >> 8].free_file(drives + (handle >> 8), handle & 0xff);
+  struct drive *d;
+  uint32_t f;
+  if (verify_file_handle(handle, &d, &f))
+    d->free_file(d, f);
 }
 
 uint32_t sc_file_get_size(uint32_t handle) {
-  if (!handle)
+  struct drive *d;
+  uint32_t f;
+  if (verify_file_handle(handle, &d, &f))
+    return d->get_file_length(d, f);
+  else
     return 0;
-  return drives[handle >> 8].get_file_length(drives + (handle >> 8), handle & 0xff);
 }
 
 void sc_file_set_size(uint32_t handle, uint32_t new_size) {
-  if (!handle)
-    return;
-  drives[handle >> 8].set_file_length(drives + (handle >> 8), handle & 0xff, new_size);
+  struct drive *d;
+  uint32_t f;
+  if (verify_file_handle(handle, &d, &f))
+    d->set_file_length(d, f, new_size);
 }
 
 uint32_t sc_file_read(uint32_t handle, uint32_t file_offset, uint32_t count, void *buffer) {
-  if (!handle)
+  struct drive *d;
+  uint32_t f;
+  if (verify_file_handle(handle, &d, &f)) {
+    const uint32_t l = d->get_file_length(d, f);
+    if (file_offset >= l)
+      return 0;
+    if (file_offset + count > l)
+      count = l - file_offset;
+    fmcpy(buffer, d, f, file_offset, count);
+    return count;
+  }
+  else
     return 0;
-  uint32_t len = sc_file_get_size(handle);
-  if (file_offset + count > len)
-    count = len - file_offset;
-  fmcpy(buffer, drives + (handle >> 8), handle & 0xff, file_offset, count);
-  return count;
 }
 
 uint32_t sc_file_write(uint32_t handle, uint32_t file_offset, uint32_t count, void *buffer) {
-  if (!handle)
+  struct drive *d;
+  uint32_t f;
+  if (verify_file_handle(handle, &d, &f)) {
+    if (!d->is_writable(d, f))
+      return 0;
+    const uint32_t l = d->get_file_length(d, f);
+    if (file_offset >= l)
+      return 0;
+    if (file_offset + count > l)
+      count = l - file_offset;
+    mfcpy(d, f, file_offset, buffer, count);
+    return l;
+  }
+  else
     return 0;
-  const struct drive *const d = drives + (handle >> 8);
-  const fs_id_t fid = handle & 0xff;
+}
 
-  if (!d->is_writable(d, fid))
+uint32_t sc_start_task(char *path, const char *pass, uint32_t io_task) {
+  struct drive *d;
+  const char *f;
+  map_path(path, &d, &f);
+  if (!d)
     return 0;
 
-  const uint32_t l = d->get_file_length(d, fid);
-  if (file_offset + count > l)
-    count = l - file_offset;
-
-  mfcpy(d, fid, file_offset, buffer, count);
-  return count;
-}
-
-uint32_t sc_start_task(uint32_t drive_number, char *path, const char *pass, uint32_t io_task) {
   switch_to_kernel_cr3();
-  uint32_t process_id = try_elf_run(drives + drive_number, vma_to_pma(active_task->page_directory, path), pass, io_task);
+  uint32_t process_id = try_elf_run(d, vma_to_pma(active_task->page_directory, f), pass, io_task);
   switch_to_task_cr3();
   return process_id;
 }
@@ -126,12 +161,18 @@ void sc_wait_for_task(uint32_t handle) {
   add_wait((struct wait){.mode = PROCESS_END, .task = tasks + handle - 1});
 }
 
-uint32_t sc_enumerate_dir(uint32_t drive_number, const char *path, struct directory_content_info *buffer, uint32_t max_entries) { //not static to ensure sysv abi
-  return drives[drive_number].enumerate_dir(drives + drive_number, path, buffer, max_entries);
+uint32_t sc_enumerate_dir(const char *path, struct directory_content_info *buffer, uint32_t max_entries) { //not static to ensure sysv abi
+  struct drive *d;
+  const char *f;
+  map_path(path, &d, &f);
+  return d ? d->enumerate_dir(d, f, buffer, max_entries) : 0;
 }
 
-uint32_t sc_count_of_dir(uint32_t drive_number, const char *path) {
-  return drives[drive_number].n_dir_entries(drives + drive_number, path);
+uint32_t sc_count_of_dir(const char *path) {
+  struct drive *d;
+  const char *f;
+  map_path(path, &d, &f);
+  return d ? d->n_dir_entries(d, f) : 0;
 }
 
 void sc_get_next_window_action(struct window *w, struct window_action *action) {