prefork-interp: ident, options

[chiark-utils.git] / cprogs / prefork-interp.c

diff --git a/cprogs/prefork-interp.c b/cprogs/prefork-interp.c
index 47ad3616a5e46b7bb7c7e546eb96deb9b31b8ae7..61dcca93bf370a578bcd5a72cc5c4ad7b12c3360 100644 (file)
--- a/cprogs/prefork-interp.c
+++ b/cprogs/prefork-interp.c
@@ -7,11 +7,27 @@
  *   prefork-interp  [<option>,..],<interpreter>   <script> [<args> ...]
  *   prefork-interp '[<option> ..] <interpreter>'  <script> [<args> ...]
  *
- * Options must specify argument laundering mode.
- * Currently the only mode supported is:
+ * Options must specify argument mediation approach.
+ * Currently the only argument mediation supported is:
+ *
  *   -U    unlaundered: setup and executor both get all arguments and env vars
  *         ident covers only env vars specified  with -E
  *         ident covers only arguments interpreter and (if present) script
+ *
+ * Options for setting the operation mode:
+ *
+ *   (none)     Default: start new server if needed, then run service
+ *   -f         Force a fresh service (old one is terminated)
+ *   --kill     Kill any existing service; do not actually run anything
+ *
+ * Options for controlling whether different invocations share a server:
+ *
+ *   -E VAR      ident includes env var VAR (or its absence)
+ *   -G STRING   ident includes string STRING
+ *   -g IDENT    use IDENT rather than hex(SHA256(... identity things ...))
+ *
+ * (Ordering of -E and -G options is relevant; invocations with different
+ * -E -G options are different even if the env var settings are the same)
  */
 
 /*
@@ -363,6 +379,7 @@
 */
 
 #include <arpa/inet.h>
+#include <sys/utsname.h>
 
 #include <uv.h>
 
@@ -404,9 +421,29 @@ const struct cmdinfo cmdinfos[]= {
   { 0 }
 };
 
+static void ident_add_stat(const char *path) {
+  struct stat stab;
+  int r = stat(path, &stab);
+  if (r) diee("failed to stat %s", path);
+
+  IDENT_ADD_OBJ(stab.st_dev);
+  IDENT_ADD_OBJ(stab.st_ino);
+}
+
 void ident_addinit(void) {
-  char ident_magic[1] = { 0 };
-  sha256_update(&identsc, sizeof(ident_magic), ident_magic);
+  char magic = 1;
+
+  IDENT_ADD_OBJ(magic);
+
+  struct utsname uts = { };
+  size_t utslen = sizeof(uts);
+  int r = uname(&uts);
+  if (r) diee("uname failed!");
+  IDENT_ADD_OBJ(utslen);
+  IDENT_ADD_OBJ(uts);
+
+  ident_add_stat(".");
+  ident_add_stat("/");
 }
 
 static void propagate_exit_status(int status, const char *what) {