Add real process nodes

* process.c, process.h: New files, implement a process
  directory with cmdline and environ files.
* Makefile: Add the process module.
* proclist.c: Replace stub pid files with the real thing.

4 files changed, 92 insertions, 4 deletions

diff --git a/Makefile b/Makefile
index 1fe7415..23815d7 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 TARGET = procfs
-OBJS = procfs.o netfs.o procfs_file.o procfs_dir.o proclist.o main.o
+OBJS = procfs.o netfs.o procfs_file.o procfs_dir.o process.o proclist.o main.o
 LIBS = -lnetfs
 
 CC = gcc
diff --git a/process.c b/process.c
new file mode 100644
index 0000000..90ea511
--- /dev/null
+++ b/process.c
@@ -0,0 +1,79 @@
+#include <stdlib.h>
+#include <hurd/process.h>
+#include "procfs.h"
+#include "procfs_dir.h"
+#include "process.h"
+
+struct process_node {
+  process_t procserv;
+  pid_t pid;
+};
+
+
+/* The proc_getprocargs() and proc_getprocenv() calls have the same
+   prototype and we use them in the same way; namely, publish the data
+   they return as-is.  We take advantage of this to have common code and
+   use a function pointer as the procfs_dir "entry hook" to choose the
+   call to use on a file by file basis.  */
+
+struct process_argz_node
+{
+  struct process_node pn;
+  error_t (*getargz) (process_t, pid_t, void **, mach_msg_type_number_t *);
+};
+
+static error_t
+process_argz_get_contents (void *hook, void **contents, size_t *contents_len)
+{
+  struct process_argz_node *pz = hook;
+  error_t err;
+
+  *contents_len = 0;
+  err = pz->getargz (pz->pn.procserv, pz->pn.pid, contents, contents_len);
+  if (err)
+    return EIO;
+
+  return 0;
+}
+
+static struct node *
+process_argz_make_node (void *dir_hook, void *entry_hook)
+{
+  static const struct procfs_node_ops ops = {
+    .get_contents = process_argz_get_contents,
+    .cleanup_contents = procfs_cleanup_contents_with_vm_deallocate,
+    .cleanup = free,
+  };
+  struct process_argz_node *zn;
+
+  zn = malloc (sizeof *zn);
+  if (! zn)
+    return NULL;
+
+  memcpy (&zn->pn, dir_hook, sizeof zn->pn);
+  zn->getargz = entry_hook;
+
+  return procfs_make_node (&ops, zn);
+}
+
+
+struct node *
+process_make_node (process_t procserv, pid_t pid)
+{
+  static const struct procfs_dir_entry entries[] = {
+    { "cmdline",	process_argz_make_node,		proc_getprocargs,	},
+    { "environ",	process_argz_make_node,		proc_getprocenv,	},
+    { NULL, }
+  };
+  struct process_node *pn;
+
+  pn = malloc (sizeof *pn);
+  if (! pn)
+    return NULL;
+
+  pn->procserv = procserv;
+  pn->pid = pid;
+
+  return procfs_dir_make_node (entries, pn, free);
+}
+
diff --git a/process.h b/process.h
new file mode 100644
index 0000000..8ca7c85
--- /dev/null
+++ b/process.h
@@ -0,0 +1,2 @@
+struct node *
+process_make_node (process_t procserv, pid_t pid);
diff --git a/proclist.c b/proclist.c
index e009ebd..148e4bc 100644
--- a/proclist.c
+++ b/proclist.c
@@ -4,8 +4,7 @@
 #include <mach.h>
 #include <hurd/process.h>
 #include "procfs.h"
-#include "procfs_file.h"
-#include "procfs_dir.h"
+#include "process.h"
 
 #define PID_STR_SIZE (3 * sizeof (pid_t) + 1)
 
@@ -49,7 +48,15 @@ proclist_get_contents (void *hook, void **contents, size_t *contents_len)
 static error_t
 proclist_lookup (void *hook, const char *name, struct node **np)
 {
-  *np = procfs_file_make_node ("Ceci n'est pas un processus\n", -1, NULL);
+  struct proclist_node *pl = hook;
+  char *endp;
+  pid_t pid;
+
+  pid = strtol (name, &endp, 10);
+  if (name[0] == '0' || !name[0] || *endp)
+    return ENOENT;
+
+  *np = process_make_node (pl->process, pid);
   return *np ? 0 : ENOMEM;
 }