Implement /proc/<pid>/exe

by adding proc_set/get_exe to the proc server, making
exec call proc_set_exe, and libps call proc_get_exe. procfs can then just
retrieve the information to make the "exe" symlink.

* hurd/process.defs (proc_set_exe, proc_get_exe): New RPCs.
* hurd/process_request.defs: Likewise.
* hurd/process_reply.defs: Add skips for proc_set_exe and proc_get_exe RPCs.
* proc/proc.h (struct proc): Add `exe' field.
* proc/info.c (S_proc_set_exe, S_proc_get_exe): New functions.
* proc/mgt.c (process_has_exited): Free p->exe.
(S_proc_child): Duplicate parent `exe' into child's `exe'.
* exec/exec.c (do_exec): Call proc_set_exe when a filename is available.
* libps/ps.h (struct proc_stat): Add `exe_vm_alloced', `exe', and `exe_len'
field.
(PSTAT_EXE): New macro.
(PSTAT_USER_BASE): Change value to make room.
(proc_stat_exe, proc_stat_exe_len): New macros.
* libps/procstat.c (proc_stat_set_flags): Handle PSTAT_EXE case by calling
proc_get_exe.
* libps/spec.c (ps_get_exe): New function.
(ps_exe_getter): New structure.
(ps_fmt_spec): Add "Exe" specification.
* procfs/process.c (process_file_symlink_make_node, process_file_gc_exe): New
functions.
(procfs_dir_entry): Add "exe" entry.
* startup/startup.c (launch_core_servers): Set exe paths for startup, auth,
proc, and fs servers.
(frob_kernel_process): Set exe path for kernel task.
(S_startup_essential_task): Set exe path for exec server.

1 files changed, 7 insertions, 0 deletions

diff --git a/startup/startup.c b/startup/startup.c
index 81a67716..9a06f7c2 100644
--- a/startup/startup.c
+++ b/startup/startup.c
@@ -832,6 +832,7 @@ launch_core_servers (void)
   assert_perror_backtrace (err);
   err = proc_mark_exec (procserver);
   assert_perror_backtrace (err);
+  proc_set_exe (procserver, "/hurd/startup");
 
   /* Declare that the filesystem and auth are our children. */
   err = proc_child (procserver, fstask);
@@ -845,6 +846,7 @@ launch_core_servers (void)
   assert_perror_backtrace (err);
   err = proc_mark_exec (authproc);
   assert_perror_backtrace (err);
+  proc_set_exe (authproc, "/hurd/auth");
 
   err = install_as_translator ();
   if (err)
@@ -883,6 +885,7 @@ launch_core_servers (void)
     {
       proc_mark_important (procproc);
       proc_mark_exec (procproc);
+      proc_set_exe (procproc, "/hurd/proc");
       mach_port_deallocate (mach_task_self (), procproc);
     }
 
@@ -898,6 +901,7 @@ launch_core_servers (void)
   assert_perror_backtrace (err);
   err = proc_mark_exec (fsproc);
   assert_perror_backtrace (err);
+  proc_set_exe (fsproc, "fs");
 
   fprintf (stderr, ".\n");
 
@@ -1045,6 +1049,8 @@ frob_kernel_process (void)
   err = record_essential_task ("kernel", task);
   assert_perror_backtrace (err);
 
+  proc_set_exe (proc, "kernel");
+
   err = task_get_bootstrap_port (task, &kbs);
   assert_perror_backtrace (err);
   if (kbs == MACH_PORT_NULL)
@@ -1455,6 +1461,7 @@ S_startup_essential_task (mach_port_t server,
           mach_port_t execproc;
           proc_task2proc (procserver, task, &execproc);
           proc_mark_important (execproc);
+          proc_set_exe (execproc, "/hurd/exec");
         }
       else if (!strcmp (name, "proc"))
 	procinit = 1;