Fetch process information and reject the non-existing ones

* process.c, process.h (process_make_node): Make static,
  include a procinfo structure into the node information.
  (process_lookup_pid): New function, replaces process_make_node as the
  outer interface, returns an error for non-existing processes.
* proclist.c (proclist_lookup): Convert to the new interface.

3 files changed, 48 insertions, 8 deletions

diff --git a/process.c b/process.c
index 90ea511..612ed49 100644
--- a/process.c
+++ b/process.c
@@ -7,6 +7,7 @@
 struct process_node {
   process_t procserv;
   pid_t pid;
+  struct procinfo info;
 };
 
 
@@ -57,8 +58,8 @@ process_argz_make_node (void *dir_hook, void *entry_hook)
 }
 
 
-struct node *
-process_make_node (process_t procserv, pid_t pid)
+static struct node *
+process_make_node (process_t procserv, pid_t pid, const struct procinfo *info)
 {
   static const struct procfs_dir_entry entries[] = {
     { "cmdline",	process_argz_make_node,		proc_getprocargs,	},
@@ -73,7 +74,34 @@ process_make_node (process_t procserv, pid_t pid)
 
   pn->procserv = procserv;
   pn->pid = pid;
+  memcpy (&pn->info, info, sizeof pn->info);
 
-  return procfs_dir_make_node (entries, pn, free);
+  return procfs_dir_make_node (entries, pn, process_cleanup);
 }
 
+error_t
+process_lookup_pid (process_t procserv, pid_t pid, struct node **np)
+{
+  procinfo_t info;
+  size_t info_sz;
+  data_t tw;
+  size_t tw_sz;
+  int flags;
+  error_t err;
+
+  tw_sz = info_sz = 0, flags = 0;
+  err = proc_getprocinfo (procserv, pid, &flags, &info, &info_sz, &tw, &tw_sz);
+  if (err == ESRCH)
+    return ENOENT;
+  if (err)
+    return EIO;
+
+  assert (info_sz * sizeof *info >= sizeof (struct procinfo));
+  *np = process_make_node (procserv, pid, (struct procinfo *) info);
+  vm_deallocate (mach_task_self (), (vm_address_t) info, info_sz);
+
+  if (! *np)
+    return ENOMEM;
+
+  return 0;
+}
diff --git a/process.h b/process.h
index 8ca7c85..abdaaa3 100644
--- a/process.h
+++ b/process.h
@@ -1,2 +1,8 @@
-struct node *
-process_make_node (process_t procserv, pid_t pid);
+#include <hurd.h>
+
+/* Create a node for a directory representing information available at
+   the proc server PROC for the given PID.  On success, returns the
+   newly created node in *NP.  */
+error_t
+process_lookup_pid (process_t proc, pid_t pid, struct node **np);
+
diff --git a/proclist.c b/proclist.c
index 148e4bc..75b61a2 100644
--- a/proclist.c
+++ b/proclist.c
@@ -52,12 +52,18 @@ proclist_lookup (void *hook, const char *name, struct node **np)
   char *endp;
   pid_t pid;
 
+  /* Self-lookups should not end up here. */
+  assert (name[0]);
+
+  /* No leading zeros allowed */
+  if (name[0] == '0' && name[1])
+    return ENOENT;
+
   pid = strtol (name, &endp, 10);
-  if (name[0] == '0' || !name[0] || *endp)
+  if (*endp)
     return ENOENT;
 
-  *np = process_make_node (pl->process, pid);
-  return *np ? 0 : ENOMEM;
+  return process_lookup_pid (pl->process, pid, np);
 }
 
 struct node *