r14652@tombo: nickm | 2007-11-02 12:02:13 -0400

 If setting our rlimit to rlim_max or cap fails, fall back to OPEN_FILES if defiled.  This makes Tor run on OSX 10.5, while allowing OSX to mend its ways in the future.


svn:r12341

3 files changed, 35 insertions, 5 deletions

diff --git a/ChangeLog b/ChangeLog
index 7aedd17534..28432b5fb4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -77,7 +77,10 @@ Changes in version 0.2.0.10-alpha - 2007-1?-??
       0.2.0.9-alpha.
 
   - Minor bugfixes (portability):
-    - Run correctly on platforms where rlim_t is larger than unsigned long.
+    - Run correctly on platforms where rlim_t is larger than unsigned
+      long.
+    - Run correctly on platforms where the real limit for number of
+      open files is OPEN_FILES, not rlim_max from getrlimit(RLIMIT_NOFILES)
 
 
 Changes in version 0.2.0.9-alpha - 2007-10-24
diff --git a/configure.in b/configure.in
index 5ad8617ab3..b465ad5bef 100644
--- a/configure.in
+++ b/configure.in
@@ -251,7 +251,7 @@ AC_CHECK_HEADERS(netdb.h sys/ioctl.h sys/socket.h arpa/inet.h netinet/in.h pwd.h
 
 dnl These headers are not essential
 
-AC_CHECK_HEADERS(stdint.h sys/types.h inttypes.h sys/param.h sys/wait.h limits.h sys/limits.h netinet/in.h arpa/inet.h machine/limits.h syslog.h sys/time.h sys/resource.h inttypes.h utime.h sys/utime.h sys/mman.h netintet/in.h netinet/in6.h malloc.h)
+AC_CHECK_HEADERS(stdint.h sys/types.h inttypes.h sys/param.h sys/wait.h limits.h sys/limits.h netinet/in.h arpa/inet.h machine/limits.h syslog.h sys/time.h sys/resource.h inttypes.h utime.h sys/utime.h sys/mman.h netintet/in.h netinet/in6.h malloc.h sys/syslimits.h)
 
 AC_CHECK_HEADERS(net/if.h, net_if_found=1, net_if_found=0,
 [#ifdef HAVE_SYS_TYPES_H
diff --git a/src/common/compat.c b/src/common/compat.c
index b46591701e..bc99a86d6e 100644
--- a/src/common/compat.c
+++ b/src/common/compat.c
@@ -94,6 +94,9 @@ const char compat_c_id[] =
 #ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
 #endif
+#ifdef HAVE_SYS_SYSLIMITS_H
+#include <sys/syslimits.h>
+#endif
 
 #ifdef USE_BSOCKETS
 #include <bsocket.h>
@@ -710,10 +713,34 @@ set_max_file_descriptors(unsigned long limit, unsigned long cap)
              (unsigned long)rlim.rlim_cur, (unsigned long)most);
   }
   rlim.rlim_cur = most;
+
   if (setrlimit(RLIMIT_NOFILE, &rlim) != 0) {
-    log_warn(LD_CONFIG, "Could not set maximum number of file descriptors: %s",
-             strerror(errno));
-    return -1;
+    int bad = 1;
+#ifdef OPEN_MAX
+    if (errno == EINVAL && OPEN_MAX < rlim.rlim_cur) {
+      /* On some platforms, OPEN_MAX is the real limit, and getrlimit() is
+       * full of nasty lies.  I'm looking at you, OSX 10.5.... */
+      rlim.rlim_cur = OPEN_MAX;
+      if (setrlimit(RLIMIT_NOFILE, &rlim) == 0) {
+        if (rlim.rlim_cur < limit) {
+          log_warn(LD_CONFIG, "We are limited to %lu file descriptors by "
+                 "OPEN_MAX, and ConnLimit is %lu.  Changing ConnLimit; sorry.",
+                   (unsigned long)OPEN_MAX, limit);
+        } else {
+          log_info(LD_CONFIG, "Dropped connection limit to OPEN_MAX (%lu); "
+                   "Apparently, %lu was too high and rlimit lied to us.",
+                   (unsigned long)OPEN_MAX, (unsigned long)most);
+        }
+        most = rlim.rlim_cur;
+        bad = 0;
+      }
+    }
+#endif
+    if (bad) {
+      log_warn(LD_CONFIG, "Couldn't set maximum number of file descriptors: %s",
+               strerror(errno));
+      return -1;
+    }
   }
   /* leave some overhead for logs, etc, */
   limit = most;