process: Switch from returning model to callback model for driver callback handling

1 files changed, 11 insertions, 5 deletions

diff --git a/src/lib/process.zig b/src/lib/process.zig
index 87fc374..5c9466c 100644
--- a/src/lib/process.zig
+++ b/src/lib/process.zig
@@ -58,11 +58,13 @@ pub const Info = struct {
     pages: []align(paging.page_size) u8,
     stack: []align(paging.page_size) u8,
     pc: usize,
-    terminate_ra: ?usize,
+    termHook: ?TermHook,
     page_table: *paging.Table,
     state: State,
     rds: std.AutoArrayHashMap(usize, vfs.ResourceDescriptor),
 
+    pub const TermHook = *const fn (proc: *const Info) void;
+
     pub fn destroy(self: *Info) !void {
         try paging.free(self.stack);
         try self.page_table.unmap();
@@ -117,7 +119,7 @@ pub const Info = struct {
             .pages = self.pages,
             .stack = stack,
             .pc = self.pc,
-            .terminate_ra = null,
+            .termHook = null,
             .page_table = self.page_table,
             .state = .suspended,
             .rds = self.rds,
@@ -130,7 +132,7 @@ pub const Info = struct {
         return &proc_node.data;
     }
 
-    pub fn call(self: *Info, function: usize, args: anytype) noreturn {
+    pub fn call(self: *Info, function: usize, args: anytype, termHook: TermHook) void {
         const Container = struct {
             fn terminate() linksection(".rethooks") callconv(.Naked) noreturn {
                 // Syscall #100011 is "terminate".
@@ -142,7 +144,7 @@ pub const Info = struct {
         };
 
         self.pc = function;
-        self.terminate_ra = @returnAddress();
+        self.termHook = termHook;
         self.trap_frame.general_purpose_registers[1] = @intFromPtr(&Container.terminate);
         inline for (args, 0..) |arg, i| {
             if (i >= 6) break;
@@ -178,6 +180,10 @@ pub const Info = struct {
 
             self.rds.deinit();
         }
+
+        if (self.termHook) |termHook| {
+            termHook(self);
+        }
     }
 
     fn shouldRemove(self: *const Info, candidate: *const Info) bool {
@@ -335,7 +341,7 @@ pub fn create(allocator: std.mem.Allocator, elf_buf: []align(@alignOf(elf.Elf64_
         .pages = pages,
         .stack = @ptrCast(stack),
         .pc = hdr.entry,
-        .terminate_ra = null,
+        .termHook = null,
         .page_table = procmem,
         .state = .waiting,
         .rds = std.AutoArrayHashMap(usize, vfs.ResourceDescriptor).init(allocator),