Fixup debug output (#1617)

libfuse/include/debug.hpp

@@ -18,39 +18,52 @@
 
 #pragma once
 
-#include <string>
-
 #include "fuse_kernel.h"
 
-void debug_fuse_open_out(const uint64_t              unique,
+#include <memory>
+#include <string>
+
+
+int fuse_debug_set_output(const std::string &filepath);
+
+void fuse_debug_open_out(const uint64_t              unique,
                          const struct fuse_open_out *arg,
                          const uint64_t              argsize);
-void debug_fuse_init_in(const struct fuse_init_in *arg);
-void debug_fuse_init_out(const uint64_t              unique,
+void fuse_debug_init_in(const struct fuse_init_in *arg);
+void fuse_debug_init_out(const uint64_t              unique,
                          const struct fuse_init_out *arg,
                          const uint64_t              argsize);
-void debug_fuse_entry_out(const uint64_t               unique,
+void fuse_debug_entry_out(const uint64_t               unique,
                           const struct fuse_entry_out *arg,
                           const uint64_t               argsize);
-void debug_fuse_attr_out(const uint64_t              unique,
+void fuse_debug_attr_out(const uint64_t              unique,
                          const struct fuse_attr_out *arg,
                          const uint64_t              argsize);
-void debug_fuse_entry_open_out(const uint64_t               unique,
+void fuse_debug_entry_open_out(const uint64_t               unique,
                                const struct fuse_entry_out *earg,
                                const struct fuse_open_out  *oarg);
-void debug_fuse_readlink(const uint64_t  unique,
+void fuse_debug_readlink(const uint64_t  unique,
                          const char     *linkname);
-void debug_fuse_write_out(const uint64_t               unique,
+void fuse_debug_write_out(const uint64_t               unique,
                           const struct fuse_write_out *arg);
-void debug_fuse_statfs_out(const uint64_t                unique,
+void fuse_debug_statfs_out(const uint64_t                unique,
                            const struct fuse_statfs_out *arg);
-void debug_fuse_getxattr_out(const uint64_t                  unique,
+void fuse_debug_getxattr_out(const uint64_t                  unique,
                              const struct fuse_getxattr_out *arg);
-void debug_fuse_lk_out(const uint64_t            unique,
+void fuse_debug_lk_out(const uint64_t            unique,
                        const struct fuse_lk_out *arg);
-void debug_fuse_bmap_out(const uint64_t              unique,
+void fuse_debug_bmap_out(const uint64_t              unique,
                          const struct fuse_bmap_out *arg);
-void debug_fuse_in_header(const struct fuse_in_header *hdr);
+void fuse_debug_statx_out(const uint64_t               unique,
+                          const struct fuse_statx_out *arg);
+void fuse_debug_data_out(const uint64_t unique,
+                         const size_t   size);
+void fuse_debug_ioctl_out(const uint64_t               unique,
+                          const struct fuse_ioctl_out *arg);
+void fuse_debug_poll_out(const uint64_t              unique,
+                         const struct fuse_poll_out *arg);
+void fuse_debug_in_header(const struct fuse_in_header *hdr);
+void fuse_debug_out_header(const struct fuse_out_header *hdr);
 
 std::string fuse_debug_init_flag_name(const uint64_t);
 

libfuse/include/fuse.h

@@ -359,9 +359,6 @@ int fuse_main(int argc,
 
 void fuse_populate_maintenance_thread(struct fuse *fuse);
 
-int  fuse_log_metrics_get(void);
-void fuse_log_metrics_set(int enabled);
-
 
 /**
  * Iterate over cache removing stale entries

libfuse/include/fuse_cfg.hpp

@@ -3,6 +3,8 @@
 #include "base_types.h"
 
 #include <climits>
+#include <cstdio>
+#include <memory>
 #include <string>
 
 #define FUSE_CFG_INVALID_ID    -1
@@ -11,6 +13,9 @@
 
 struct fuse_cfg_t
 {
+  template<typename T>
+  using sp = std::shared_ptr<T>;
+
   s64 uid = FUSE_CFG_INVALID_ID;
   bool valid_uid() const;
 
@@ -23,7 +28,15 @@ struct fuse_cfg_t
   s64 remember_nodes = 0;
 
   bool debug = false;
+  std::shared_ptr<FILE> log_file() const;
+  void log_file(std::shared_ptr<FILE>);
+  std::shared_ptr<std::string> log_filepath() const;
+  void log_filepath(const std::string &);
+private:
+  std::shared_ptr<FILE>        _log_file     = sp<FILE>(stderr,[](FILE*){});
+  std::shared_ptr<std::string> _log_filepath = sp<std::string>();
 
+public:
   int max_background = 0;
   int congestion_threshold = 0;
   u32 max_pages = 32;

libfuse/lib/fuse.cpp

@@ -14,6 +14,7 @@
 #include "syslog.hpp"
 
 #include "crc32b.h"
+#include "debug.hpp"
 #include "khash.h"
 #include "kvec.h"
 #include "mutex.hpp"
@@ -67,8 +68,6 @@
 
 #define PARAM(inarg) ((void*)(((char*)(inarg)) + sizeof(*(inarg))))
 
-static int g_LOG_METRICS = 0;
-
 struct fuse_config
 {
 };
@@ -3752,7 +3751,7 @@ fuse_populate_maintenance_thread(struct fuse *f_)
 
   MaintenanceThread::push_job([=](int count_)
   {
-    if(g_LOG_METRICS)
+    if(fuse_cfg.debug)
       metrics_log_nodes_info_to_tmp_dir(f_);
   });
 }
@@ -3777,8 +3776,6 @@ fuse_new(struct fuse_chan             *ch,
   if(fuse_opt_parse(args,&f.conf,fuse_lib_opts,fuse_lib_opt_proc) == -1)
     goto out_free_fs;
 
-  g_LOG_METRICS = fuse_cfg.debug;
-
   f.se = fuse_lowlevel_new_common(args,&llop,sizeof(llop),&f);
   if(f.se == NULL)
     goto out_free_fs;
@@ -3854,18 +3851,6 @@ fuse_destroy(struct fuse *)
   kv_destroy(f.remembered_nodes);
 }
 
-void
-fuse_log_metrics_set(int log_)
-{
-  g_LOG_METRICS = log_;
-}
-
-int
-fuse_log_metrics_get(void)
-{
-  return g_LOG_METRICS;
-}
-
 int
 fuse_passthrough_open(const int fd_)
 {

libfuse/lib/fuse_cfg.cpp

@@ -19,3 +19,28 @@ fuse_cfg_t::valid_umask() const
 {
   return (umask != FUSE_CFG_INVALID_UMASK);
 }
+
+std::shared_ptr<FILE>
+fuse_cfg_t::log_file() const
+{
+  return std::atomic_load(&_log_file);
+}
+
+void
+fuse_cfg_t::log_file(std::shared_ptr<FILE> f_)
+{
+  std::atomic_store(&_log_file, f_);
+}
+
+std::shared_ptr<std::string>
+fuse_cfg_t::log_filepath() const
+{
+  return std::atomic_load(&_log_filepath);
+}
+
+void
+fuse_cfg_t::log_filepath(const std::string &s_)
+{
+  std::atomic_store(&_log_filepath,
+                    std::make_shared<std::string>(s_));
+}

libfuse/lib/fuse_lowlevel.cpp

@@ -240,6 +240,15 @@ int
 fuse_reply_err(fuse_req_t *req_,
                int         err_)
 {
+  if(fuse_cfg.debug)
+    {
+      struct fuse_out_header hdr = {};
+      hdr.unique = req_->ctx.unique;
+      hdr.error  = (err_ > 0) ? -err_ : err_;
+      hdr.len    = sizeof(struct fuse_out_header);
+      fuse_debug_out_header(&hdr);
+    }
+
   return send_reply(req_,err_,NULL,0);
 }
 
@@ -308,6 +317,9 @@ fuse_reply_entry(fuse_req_t                    *req,
   // the kernel.
 #endif
 
+  if(fuse_cfg.debug)
+    fuse_debug_entry_out(req->ctx.unique,&arg,size);
+
   return send_reply_ok(req, &arg, size);
 }
 
@@ -331,6 +343,9 @@ fuse_reply_create(fuse_req_t                    *req,
   fill_entry(earg, e);
   fill_open(oarg, f);
 
+  if(fuse_cfg.debug)
+    fuse_debug_entry_open_out(req->ctx.unique,earg,oarg);
+
   return send_reply_ok(req, &buf, entrysize + sizeof(struct fuse_open_out));
 }
 
@@ -347,6 +362,9 @@ fuse_reply_attr(fuse_req_t        *req,
   arg.attr_valid_nsec = 0;
   convert_stat(attr,&arg.attr);
 
+  if(fuse_cfg.debug)
+    fuse_debug_attr_out(req->ctx.unique,&arg,size);
+
   return send_reply_ok(req,&arg,size);
 }
 
@@ -363,6 +381,9 @@ fuse_reply_statx(fuse_req_t        *req_,
   outarg.attr_valid_nsec = 0;
   outarg.stat            = *(struct fuse_statx*)st_;
 
+  if(fuse_cfg.debug)
+    fuse_debug_statx_out(req_->ctx.unique,&outarg);
+
   return send_reply_ok(req_,&outarg,sizeof(outarg));
 }
 
@@ -370,6 +391,9 @@ int
 fuse_reply_readlink(fuse_req_t *req,
                     const char *linkname)
 {
+  if(fuse_cfg.debug)
+    fuse_debug_readlink(req->ctx.unique,linkname);
+
   return send_reply_ok(req, linkname, strlen(linkname));
 }
 
@@ -381,6 +405,9 @@ fuse_reply_open(fuse_req_t             *req,
 
   fill_open(&arg, f);
 
+  if(fuse_cfg.debug)
+    fuse_debug_open_out(req->ctx.unique,&arg,sizeof(arg));
+
   return send_reply_ok(req, &arg, sizeof(arg));
 }
 
@@ -392,6 +419,9 @@ fuse_reply_write(fuse_req_t *req,
 
   arg.size = count;
 
+  if(fuse_cfg.debug)
+    fuse_debug_write_out(req->ctx.unique,&arg);
+
   return send_reply_ok(req, &arg, sizeof(arg));
 }
 
@@ -400,6 +430,9 @@ fuse_reply_buf(fuse_req_t *req,
                const char *buf,
                size_t      size)
 {
+  if(fuse_cfg.debug)
+    fuse_debug_data_out(req->ctx.unique,size);
+
   return send_reply_ok(req, buf, size);
 }
 
@@ -436,6 +469,9 @@ fuse_reply_data(fuse_req_t   *req,
   out.unique = req->ctx.unique;
   out.error = 0;
 
+  if(fuse_cfg.debug)
+    fuse_debug_data_out(req->ctx.unique,bufsize_);
+
   res = fuse_send_msg(req->f,req->ch,iov,2);
   if(res <= 0)
     {
@@ -458,6 +494,9 @@ fuse_reply_statfs(fuse_req_t           *req,
 
   convert_statfs(stbuf, &arg.st);
 
+  if(fuse_cfg.debug)
+    fuse_debug_statfs_out(req->ctx.unique,&arg);
+
   return send_reply_ok(req, &arg, size);
 }
 
@@ -469,6 +508,9 @@ fuse_reply_xattr(fuse_req_t *req,
 
   arg.size = count;
 
+  if(fuse_cfg.debug)
+    fuse_debug_getxattr_out(req->ctx.unique,&arg);
+
   return send_reply_ok(req, &arg, sizeof(arg));
 }
 
@@ -489,6 +531,9 @@ fuse_reply_lock(fuse_req_t         *req,
     }
   arg.lk.pid = lock->l_pid;
 
+  if(fuse_cfg.debug)
+    fuse_debug_lk_out(req->ctx.unique,&arg);
+
   return send_reply_ok(req, &arg, sizeof(arg));
 }
 
@@ -500,6 +545,9 @@ fuse_reply_bmap(fuse_req_t *req,
 
   arg.block = idx;
 
+  if(fuse_cfg.debug)
+    fuse_debug_bmap_out(req->ctx.unique,&arg);
+
   return send_reply_ok(req, &arg, sizeof(arg));
 }
 
@@ -541,6 +589,9 @@ fuse_reply_ioctl_retry(fuse_req_t         *req,
   arg.flags |= FUSE_IOCTL_RETRY;
   arg.in_iovs = in_count;
   arg.out_iovs = out_count;
+
+  if(fuse_cfg.debug)
+    fuse_debug_ioctl_out(req->ctx.unique,&arg);
   iov[count].iov_base = &arg;
   iov[count].iov_len = sizeof(arg);
   count++;
@@ -619,6 +670,9 @@ fuse_reply_ioctl(fuse_req_t *req,
   arg.in_iovs  = 0;
   arg.out_iovs = 0;
 
+  if(fuse_cfg.debug)
+    fuse_debug_ioctl_out(req->ctx.unique,&arg);
+
   count = 1;
   iov[count].iov_base = &arg;
   iov[count].iov_len  = sizeof(arg);
@@ -649,6 +703,10 @@ fuse_reply_ioctl_iov(fuse_req_t         *req,
     return fuse_reply_err(req, ENOMEM);
 
   arg.result = result;
+
+  if(fuse_cfg.debug)
+    fuse_debug_ioctl_out(req->ctx.unique,&arg);
+
   padded_iov[1].iov_base = &arg;
   padded_iov[1].iov_len = sizeof(arg);
 
@@ -668,6 +726,9 @@ fuse_reply_poll(fuse_req_t *req,
 
   arg.revents = revents;
 
+  if(fuse_cfg.debug)
+    fuse_debug_poll_out(req->ctx.unique,&arg);
+
   return send_reply_ok(req, &arg, sizeof(arg));
 }
 
@@ -1272,6 +1333,9 @@ do_init(fuse_req_t            *req,
 
   fuse_syslog_fuse_init_out(&outarg);
 
+  if(fuse_cfg.debug)
+    fuse_debug_init_out(req->ctx.unique,&outarg,outargsize);
+
   send_reply_ok(req, &outarg, outargsize);
 }
 
@@ -1722,9 +1786,13 @@ fuse_send_errno(struct fuse_ll   *f_,
 
   out.unique   = unique_id_;
   out.error    = -errno_;
+  out.len      = sizeof(struct fuse_out_header);
   iov.iov_base = &out;
   iov.iov_len  = sizeof(struct fuse_out_header);
 
+  if(fuse_cfg.debug)
+    fuse_debug_out_header(&out);
+
   fuse_send_msg(f_,ch_,&iov,1);
 }
 
@@ -1777,6 +1845,9 @@ fuse_ll_buf_process_read(struct fuse_session *se_,
 
   in = (struct fuse_in_header*)msgbuf_->mem;
 
+  if(fuse_cfg.debug)
+    fuse_debug_in_header(in);
+
   req = fuse_ll_alloc_req(se_->f);
   if(req == NULL)
     return fuse_send_enomem(se_->f,se_->ch,in->unique);
@@ -1817,6 +1888,9 @@ fuse_ll_buf_process_read_init(struct fuse_session *se_,
 
   in = (struct fuse_in_header*)msgbuf_->mem;
 
+  if(fuse_cfg.debug)
+    fuse_debug_in_header(in);
+
   req = fuse_ll_alloc_req(se_->f);
   if(req == NULL)
     return fuse_send_enomem(se_->f,se_->ch,in->unique);

mkdocs/docs/support.md

@@ -24,32 +24,37 @@ directly.](mailto:support@spawn.link)**
 * Solution already ruled out and why.
 * The details from the output of the
   [mergerfs.collect-info](tooling.md#mergerfscollect-info) tool.
-* Alternatively:
-    * Version of mergerfs: `mergerfs --version`
-    * mergerfs settings / arguments: from fstab, systemd unit, command
-      line, OMV plugin, etc.
-    * Version of the OS: `uname -a` and `lsb_release -a`
-    * List of branches, their filesystem types, sizes (before and after
-      issue): `df -h`, `lsblk -o NAME,FSTYPE,FSSIZE,SIZE,MOUNTPOINTS,RM,RO,ROTA`
-* **All** information about the relevant paths and files: permissions, ownership, etc.
-* **All** information about the application making the requests: version, uid/gid
+* **All** information about the relevant paths and files: permissions,
+  ownership, etc. Some of this is collected by the tool but only the
+  branch root details.
+* **All** information about the application making the requests:
+  version, uid/gid. Try though to replicate any issues with common
+  core utilities.
+* Try to recreate the problem in the simplest way using standard
+  programs: `ln`, `mv`, `cp`, `ls`, `dd`, etc. With the most simple
+  mergerfs setup possible such as using only a single branch, well
+  supported branch filesystem, maybe reduce to using a single thread,
+  etc.
 * Runtime environment:
     * Is mergerfs running within a container?
     * Are the client apps using mergerfs running in a container?
 * A `strace` of the app having problems:
     * `strace -fvTtt -s 256 -o /tmp/app.strace.txt <cmd>`
-* A `strace` of mergerfs **while** the program is trying to do
-  whatever it is failing to do:
-    * `strace -fvTtt -s 256 -p <mergerfsPID> -o /tmp/mergerfs.strace.txt`
-* **Precise** directions on replicating the issue. Do not leave
-  **anything** out.
-* Try to recreate the problem in the simplest way using standard
-  programs: `ln`, `mv`, `cp`, `ls`, `dd`, etc. With the most simple
-  mergerfs setup possible.
+* A `strace` of mergerfs **before** and **while** the program is
+  trying to do whatever it is failing to do:
+    * `strace -fvTtt -s 256 -p <mergerfsPID> -o
+      /tmp/mergerfs.strace.txt`
+* If mergerfs is blocking or appears stuck:
+    * `gdb -q --batch -ex "set pagination off" -ex "thread apply all
+      bt full" -ex quit --pid <mergerfsPID> > /tmp/mergerfs.stacktrace.txt`
+* **Precise** step-by-step directions on replicating the issue. Do not
+  leave **anything** out.
 
 
 ### Contact / Issue submission
 
+In order of preference.
+
 * github.com: [https://github.com/trapexit/mergerfs/issues](https://github.com/trapexit/mergerfs/issues)
 * discord: [https://discord.gg/MpAr69V](https://discord.gg/MpAr69V)
 * reddit: [https://www.reddit.com/r/mergerfs](https://www.reddit.com/r/mergerfs)

src/config.cpp

@@ -110,7 +110,7 @@ Config::Config()
   lazy_umount_mountpoint(false),
   link_cow(false),
   link_exdev(LinkEXDEV::ENUM::PASSTHROUGH),
-  log_metrics(false),
+  log_file({}),
   minfreespace(branches.minfreespace),
   mountpoint(),
   moveonenospc(true),
@@ -137,7 +137,7 @@ Config::Config()
   xattr(XAttr::ENUM::PASSTHROUGH),
 
   _congestion_threshold(fuse_cfg.congestion_threshold),
-  _debug(fuse_cfg.debug),
+  _debug(false),
   _gid(fuse_cfg.gid),
   _max_background(fuse_cfg.max_background),
   _mount(mountpoint),
@@ -260,7 +260,7 @@ Config::Config()
   _map["lazy-umount-mountpoint"]      = &lazy_umount_mountpoint;
   _map["link-cow"]                    = &link_cow;
   _map["link-exdev"]                  = &link_exdev;
-  _map["log.metrics"]                 = &log_metrics;
+  _map["log.file"]                    = &log_file;
   _map["minfreespace"]                = &minfreespace;
   _map["mount"]                       = &_mount;
   _map["mountpoint"]                  = &_mountpoint;

src/config.hpp

@@ -19,12 +19,13 @@
 #include "branches.hpp"
 #include "category.hpp"
 #include "config_cachefiles.hpp"
+#include "config_debug.hpp"
 #include "config_dummy.hpp"
 #include "config_flushonclose.hpp"
 #include "config_follow_symlinks.hpp"
 #include "config_inodecalc.hpp"
 #include "config_link_exdev.hpp"
-#include "config_log_metrics.hpp"
+#include "config_log_file.hpp"
 #include "config_moveonenospc.hpp"
 #include "config_nfsopenhack.hpp"
 #include "config_noforget.hpp"
@@ -140,7 +141,7 @@ public:
   ConfigBOOL     lazy_umount_mountpoint;
   ConfigBOOL     link_cow;
   LinkEXDEV      link_exdev;
-  LogMetrics     log_metrics;
+  LogFile        log_file;
   TFSRef<u64>    minfreespace;
   fs::path       mountpoint;
   MoveOnENOSPC   moveonenospc;
@@ -169,7 +170,7 @@ public:
 
 private:
   TFSRef<int>      _congestion_threshold;
-  TFSRef<bool>     _debug;
+  Debug            _debug;
   CfgDummy         _dummy;
   TFSRef<s64>      _gid;
   TFSRef<int>      _max_background;
@@ -201,6 +202,7 @@ public:
   void keys_xattr(std::string &s) const;
   ssize_t keys_listxattr(char *list, size_t size) const;
   ssize_t keys_listxattr_size() const;
+  const Str2TFStrMap& get_map() const { return _map; }
 
 public:
   int get(const std::string &key, std::string *val) const;

src/config_debug.cpp

@@ -0,0 +1,63 @@
+/*
+  ISC License
+
+  Copyright (c) 2026, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "config_debug.hpp"
+
+#include "debug.hpp"
+#include "from_string.hpp"
+#include "fuse_cfg.hpp"
+#include "to_string.hpp"
+
+#include <memory>
+#include <string>
+
+Debug::Debug(const bool v_)
+{
+  fuse_cfg.debug = v_;
+}
+
+std::string
+Debug::to_string(void) const
+{
+  return str::to(fuse_cfg.debug);
+}
+
+int
+Debug::from_string(const std::string_view s_)
+{
+  int rv;
+  bool val;
+
+  rv = str::from(s_,&val);
+  if(rv < 0)
+    return rv;
+
+  fuse_cfg.debug = val;
+
+  // If debug is being enabled, ensure output file is set
+  if(val)
+    {
+      auto log_file_path = fuse_cfg.log_filepath();
+      if(log_file_path && !log_file_path->empty())
+        fuse_debug_set_output(*log_file_path);
+      else
+        fuse_debug_set_output({}); // Use stderr
+    }
+
+  return 0;
+}

src/config_debug.hpp

@@ -0,0 +1,31 @@
+/*
+  ISC License
+
+  Copyright (c) 2026, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#pragma once
+
+#include "tofrom_string.hpp"
+
+class Debug : public ToFromString
+{
+public:
+  Debug(const bool);
+
+public:
+  std::string to_string(void) const final;
+  int from_string(const std::string_view) final;
+};

src/config_log_file.cpp

@@ -16,38 +16,31 @@
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
-#include "config_log_metrics.hpp"
-#include "from_string.hpp"
-#include "to_string.hpp"
+#include "config_log_file.hpp"
 
-#include "fuse.h"
+#include "debug.hpp"
+#include "fuse_cfg.hpp"
 
-LogMetrics::LogMetrics(const bool val_)
+#include <memory>
+#include <string>
+
+LogFile::LogFile(const std::string &s_)
 {
-  fuse_log_metrics_set(val_);
+  fuse_debug_set_output(s_);
 }
 
 std::string
-LogMetrics::to_string(void) const
+LogFile::to_string(void) const
 {
-  bool val;
+  auto filepath = fuse_cfg.log_filepath();
 
-  val = fuse_log_metrics_get();
-
-  return str::to(val);
+  return (filepath ? *filepath : "");
 }
 
 int
-LogMetrics::from_string(const std::string_view s_)
+LogFile::from_string(const std::string_view s_)
 {
-  int rv;
-  bool val;
+  const std::string s{s_};
 
-  rv = str::from(s_,&val);
-  if(rv < 0)
-    return rv;
-
-  fuse_log_metrics_set(val);
-
-  return 0;
+  return fuse_debug_set_output(s);
 }

src/config_log_file.hpp

@@ -20,10 +20,10 @@
 
 #include "tofrom_string.hpp"
 
-class LogMetrics : public ToFromString
+class LogFile : public ToFromString
 {
 public:
-  LogMetrics(const bool);
+  LogFile(const std::string &);
 
 public:
   std::string to_string(void) const final;

src/fuse_init.cpp

@@ -233,5 +233,13 @@ FUSE::init(fuse_conn_info *conn_)
       SysLog::warning("passthrough and cache.writeback are incompatible.");
     }
 
+  SysLog::info("Config:");
+  for(const auto &kv : cfg.get_map())
+    {
+      if(not kv.second->display)
+        continue;
+      SysLog::info("{}={}",kv.first,kv.second->to_string());
+    }
+
   return NULL;
 }

src/mergerfs.cpp

@@ -315,12 +315,16 @@ _main(int    argc_,
   SysLog::info("mergerfs v{} started",MERGERFS_VERSION);
   SysLog::info("Go to https://trapexit.github.io/mergerfs/latest/support for support");
 
+  for(int i = 0; i < argc_; i++)
+    SysLog::info("argv[{}]: {}",i,argv_[i]);
+
   options::parse(&args);
+
   if(!cfg.errs.empty())
     {
       for(auto &err : cfg.errs)
         {
-          std::string s = err.to_string();
+          const std::string s = err.to_string();
 
           SysLog::error("error: {}",s);
           fmt::println(stderr,"mergerfs: ERROR - {}",s);

src/mergerfs_collect_info.cpp

@@ -172,6 +172,12 @@ _lshw(const std::string &output_)
   ::_run({"lshw"},output_);
 }
 
+static
+void
+_journalctl(const std::string &output_)
+{
+  ::_run({"journalctl","-t","mergerfs","--since","60 minutes ago"},output_);
+}
 
 int
 mergerfs::collect_info::main(int    argc_,
@@ -208,6 +214,7 @@ mergerfs::collect_info::main(int    argc_,
   ::_fstab(output_filepath);
   ::_software_versions(output_filepath);
   ::_lshw(output_filepath);
+  ::_journalctl(output_filepath);
 
   fmt::print("* Upload the following file to your"
              " GitHub ticket or put on https://pastebin.com"