* amd/amq_subr.c (amqproc_pawd_1_svc): repeatedly resolve path in

Amd, not in pawd (to avoid repeated network RPCs).

* amq/pawd.c (transform_dir): move repeated path resolution into Amd.

diff --git a/ChangeLog b/ChangeLog
index d9f1fc69cbb520092c136fd4e0ad8c70a2d13eae..14838ba4de20377bcb542e7903e750b73459334a 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2005-10-26  Erez Zadok  <ezk@cs.sunysb.edu>
+
+       * amd/amq_subr.c (amqproc_pawd_1_svc): repeatedly resolve path in
+       Amd, not in pawd (to avoid repeated network RPCs).
+
+       * amq/pawd.c (transform_dir): move repeated path resolution into Amd.
+
 2005-10-25  Erez Zadok  <ezk@cs.sunysb.edu>
 
        * amq/pawd.c (transform_dir): resolve path repeatedly until

diff --git a/amd/amq_subr.c b/amd/amq_subr.c
index 861550876fef0ff48e0a322ebd20a5b3338db759..10cdd721b148383bf6d497fda1ecd889e3f07535 100644 (file)
--- a/amd/amq_subr.c
+++ b/amd/amq_subr.c
@@ -192,37 +192,58 @@ amqproc_getpid_1_svc(voidp argp, struct svc_req *rqstp)
 }
 
 
-/* process PAWD string of remote pawd tool */
+/*
+ * Process PAWD string of remote pawd tool.
+ *
+ * We repeat the resolution of the string until the resolved string resolves
+ * to itself.  This ensures that we follow path resolutions through all
+ * possible Amd mount points until we reach some sort of convergence.  To
+ * prevent possible infinite loops, we break out of this loop if the strings
+ * do not converge after MAX_PAWD_TRIES times.
+ */
 amq_string *
 amqproc_pawd_1_svc(voidp argp, struct svc_req *rqstp)
 {
   static amq_string res;
-  int index, len;
+#define MAX_PAWD_TRIES 10
+  int index, len, maxagain = MAX_PAWD_TRIES;
   am_node *mp;
   char *mountpoint;
   char *dir = *(char **) argp;
   static char tmp_buf[MAXPATHLEN];
-
-  tmp_buf[0] = '\0';           /* default is empty string: no match */
-  for (mp = get_first_exported_ap(&index);
-       mp;
-       mp = get_next_exported_ap(&index)) {
-    if (STREQ(mp->am_mnt->mf_ops->fs_type, "toplvl"))
-      continue;
-    if (STREQ(mp->am_mnt->mf_ops->fs_type, "auto"))
-      continue;
-    mountpoint = (mp->am_link ? mp->am_link : mp->am_mnt->mf_mount);
-    len = strlen(mountpoint);
-    if (len == 0)
-      continue;
-    if (!NSTREQ(mountpoint, dir, len))
-      continue;
-    if (dir[len] != '\0' && dir[len] != '/')
-      continue;
-    xstrlcpy(tmp_buf, mp->am_path, sizeof(tmp_buf));
-    xstrlcat(tmp_buf, &dir[len], sizeof(tmp_buf));
-    break;
-  }
+  char prev_buf[MAXPATHLEN];
+
+  tmp_buf[0] = prev_buf[0] = '\0'; /* default is empty string: no match */
+  do {
+    for (mp = get_first_exported_ap(&index);
+        mp;
+        mp = get_next_exported_ap(&index)) {
+      if (STREQ(mp->am_mnt->mf_ops->fs_type, "toplvl"))
+       continue;
+      if (STREQ(mp->am_mnt->mf_ops->fs_type, "auto"))
+       continue;
+      mountpoint = (mp->am_link ? mp->am_link : mp->am_mnt->mf_mount);
+      len = strlen(mountpoint);
+      if (len == 0)
+       continue;
+      if (!NSTREQ(mountpoint, dir, len))
+       continue;
+      if (dir[len] != '\0' && dir[len] != '/')
+       continue;
+      xstrlcpy(tmp_buf, mp->am_path, sizeof(tmp_buf));
+      xstrlcat(tmp_buf, &dir[len], sizeof(tmp_buf));
+      break;
+    } /* end of "for" loop */
+    /* once tmp_buf and prev_buf are equal, break out of "do" loop */
+    if (STREQ(tmp_buf, prev_buf))
+      break;
+    else
+      xstrlcpy(prev_buf, tmp_buf, sizeof(prev_buf));
+  } while (--maxagain);
+  /* check if we couldn't resolve the string after MAX_PAWD_TRIES times */
+  if (maxagain <= 0)
+    plog(XLOG_WARNING, "path \"%s\" did not resolve after %d tries",
+        tmp_buf, MAX_PAWD_TRIES);
 
   res = tmp_buf;
   return &res;

diff --git a/amq/pawd.c b/amq/pawd.c
index a7d77f6551351167e3f6efb2e8b293a2d5e5c239..1b442020c0d6d6c5475fb3a79afb9ae70c66e180 100644 (file)
--- a/amq/pawd.c
+++ b/amq/pawd.c
@@ -57,8 +57,6 @@
 #include <am_defs.h>
 #include <amq.h>
 
-/* maximum number of transformations for each path */
-#define MAX_LOOP       10
 
 /* statics */
 static char *localhost = "localhost";
@@ -185,7 +183,6 @@ transform_dir(char *dir)
   struct timeval tmo = {10, 0};
   char *dummystr;
   amq_string *spp;
-  int again = 1, maxloop = MAX_LOOP;
 
 #ifdef DISK_HOME_HACK
   if (ch = hack_name(dir))
@@ -212,21 +209,11 @@ transform_dir(char *dir)
     return dir;
 
   xstrlcpy(transform, dir, sizeof(transform));
-  while (again) {
-    if (--maxloop <= 0) {
-      fprintf(stderr, "pawd: exceeded maximum no. of transformations (%d)\n",
-             MAX_LOOP);
-      break;
-    }
-    again = 0;
-    dummystr = transform;
-    spp = amqproc_pawd_1((amq_string *) &dummystr, clnt);
-    if (spp && *spp && **spp) {
-      if (STREQ(transform, *spp))
-       again++;
-      xstrlcpy(transform, *spp, sizeof(transform));
-      XFREE(*spp);
-    }
+  dummystr = transform;
+  spp = amqproc_pawd_1((amq_string *) &dummystr, clnt);
+  if (spp && *spp && **spp) {
+    xstrlcpy(transform, *spp, sizeof(transform));
+    XFREE(*spp);
   }
   clnt_destroy(clnt);
   return transform;