Allow a path to be specified for the chansrv log file

docs/man/sesman.ini.5.in

@@ -98,7 +98,33 @@ stdout. Use for debugging only\fR
 
 It is ignored in the [ChansrvLogging] section
 since the channel server creates one log file per display and instead uses the
-following log file naming convention \fIxrdp-chansrv.${DISPLAY}.log\fR
+following log file naming convention \fIxrdp-chansrv.${DISPLAY}.log\fR. For
+details of the chansrv log file location, see \fBLogFilePath\fR.
+
+.TP
+\fBLogFilePath\fR=\fIstring\fR
+Directory for storing the chansrv log file. This setting only applies to
+chansrv. The sesman log file is always created in \fI@localstatedir@/log\fR.
+
+Created if it doesn't exist.
+If first character is not a '/', this is relative to $HOME, where
+chansrv is normally started.
+
+.RS
+The following substitutions are made in this string:-
+    %U - Username
+    %u - Numeric UID
+    %% - Percent character
+
+This is most useful if you are using NFS-mounted home directories, and
+wish to move the chansrv log file to the local disk.
+
+If this parameter isn't specified, the log file is stored in one of
+the following locations :-
+    -   $CHANSRV_LOG_PATH
+    -   $XDG_DATA_HOME/xrdp
+    -   $HOME/.local/share/xrdp
+.RE
 
 .TP
 \fBLogLevel\fR=\fIlevel\fR

sesman/chansrv/chansrv.c

@@ -1694,27 +1694,49 @@ get_log_path(char *path, int bytes)
     int rv;
 
     rv = 1;
-    log_path = g_getenv("CHANSRV_LOG_PATH");
-    if (log_path == 0)
+    if (g_cfg->log_file_path != NULL && g_cfg->log_file_path[0] != '\0')
     {
-        log_path = g_getenv("XDG_DATA_HOME");
-        if (log_path != 0)
+        char uidstr[64];
+        char username[64];
+        const struct info_string_tag map[] =
         {
-            g_snprintf(path, bytes, "%s%s", log_path, "/xrdp");
-            if (g_directory_exist(path) || (g_mkdir(path) == 0))
-            {
-                rv = 0;
-            }
+            {'u', uidstr},
+            {'U', username},
+            INFO_STRING_END_OF_LIST
+        };
+
+        int uid = g_getuid();
+        g_snprintf(uidstr, sizeof(uidstr), "%d", uid);
+        if (g_getlogin(username, sizeof(username)) != 0)
+        {
+            /* Fall back to UID */
+            g_strncpy(username, uidstr, sizeof(username) - 1);
+        }
+
+        (void)g_format_info_string(path, bytes, g_cfg->log_file_path, map);
+        if (g_directory_exist(path) || (g_mkdir(path) == 0))
+        {
+            rv = 0;
         }
     }
-    else
+    else if ((log_path = g_getenv("CHANSRV_LOG_PATH")) != 0)
     {
         g_snprintf(path, bytes, "%s", log_path);
         if (g_directory_exist(path) || (g_mkdir(path) == 0))
         {
             rv = 0;
         }
     }
+    else if ((log_path = g_getenv("XDG_DATA_HOME")) != 0)
+    {
+        g_snprintf(path, bytes, "%s%s", log_path, "/xrdp");
+        if (g_directory_exist(path) || (g_mkdir(path) == 0))
+        {
+            rv = 0;
+        }
+    }
+
+    // Always fall back to the home directory
     if (rv != 0)
     {
         log_path = g_getenv("HOME");
@@ -1830,14 +1852,6 @@ main(int argc, char **argv)
     g_init("xrdp-chansrv"); /* os_calls */
     g_memset(g_drdynvcs, 0, sizeof(g_drdynvcs));
 
-    log_path[255] = 0;
-    if (get_log_path(log_path, 255) != 0)
-    {
-        g_writeln("error reading CHANSRV_LOG_PATH and HOME environment variable");
-        main_cleanup();
-        return 1;
-    }
-
     display_text = g_getenv("DISPLAY");
     if (display_text == NULL)
     {
@@ -1864,6 +1878,13 @@ main(int argc, char **argv)
     }
     config_dump(g_cfg);
 
+    if (get_log_path(log_path, sizeof(log_path)) != 0)
+    {
+        g_writeln("error reading CHANSRV_LOG_PATH and HOME environment variable");
+        main_cleanup();
+        return 1;
+    }
+
     pid = g_getpid();
 
     /* starting logging subsystem */

sesman/chansrv/chansrv_config.c

@@ -46,6 +46,7 @@
 #define DEFAULT_NUM_SILENT_FRAMES_AAC       4
 #define DEFAULT_NUM_SILENT_FRAMES_MP3       2
 #define DEFAULT_MSEC_DO_NOT_SEND            1000
+#define DEFAULT_LOG_FILE_PATH               ""
 /**
  * Type used for passing a logging function about
  */
@@ -248,6 +249,45 @@ read_config_chansrv(log_func_t logmsg,
     return error;
 }
 
+/***************************************************************************//**
+ * Reads the config values we need from the [ChansrvLogging] section
+ *
+ * @param logmsg Function to use to log messages
+ * @param names List of definitions in the section
+ * @params values List of corresponding values for the names
+ * @params cfg Pointer to structure we're filling in
+ *
+ * @return 0 for success
+ */
+static int
+read_config_chansrv_logging(log_func_t logmsg,
+                            struct list *names, struct list *values,
+                            struct config_chansrv *cfg)
+{
+    int error = 0;
+    int index;
+
+    for (index = 0; index < names->count; ++index)
+    {
+        const char *name = (const char *)list_get_item(names, index);
+        const char *value = (const char *)list_get_item(values, index);
+
+        if (g_strcasecmp(name, "LogFilePath") == 0)
+        {
+            g_free(cfg->log_file_path);
+            cfg->log_file_path = g_strdup(value);
+            if (cfg->log_file_path == NULL)
+            {
+                logmsg(LOG_LEVEL_ERROR, "Can't alloc LogFilePath");
+                error = 1;
+                break;
+            }
+        }
+    }
+
+    return error;
+}
+
 /***************************************************************************//**
  * @brief returns a config block with default values
  *
@@ -259,9 +299,11 @@ new_config(void)
     /* Do all the allocations at the beginning, then check them together */
     struct config_chansrv *cfg = g_new0(struct config_chansrv, 1);
     char *fuse_mount_name = g_strdup(DEFAULT_FUSE_MOUNT_NAME);
-    if (cfg == NULL || fuse_mount_name == NULL)
+    char *log_file_path = g_strdup(DEFAULT_LOG_FILE_PATH);
+    if (cfg == NULL || fuse_mount_name == NULL || log_file_path == NULL)
     {
         /* At least one memory allocation failed */
+        g_free(log_file_path);
         g_free(fuse_mount_name);
         g_free(cfg);
         cfg = NULL;
@@ -279,6 +321,7 @@ new_config(void)
         cfg->num_silent_frames_aac = DEFAULT_NUM_SILENT_FRAMES_AAC;
         cfg->num_silent_frames_mp3 = DEFAULT_NUM_SILENT_FRAMES_MP3;
         cfg->msec_do_not_send = DEFAULT_MSEC_DO_NOT_SEND;
+        cfg->log_file_path = log_file_path;
     }
 
     return cfg;
@@ -329,6 +372,12 @@ config_read(int use_logger, const char *sesman_ini)
                 error = read_config_chansrv(logmsg, names, values, cfg);
             }
 
+            if (!error &&
+                    file_read_section(fd, "ChansrvLogging", names, values) == 0)
+            {
+                error = read_config_chansrv_logging(logmsg, names, values, cfg);
+            }
+
             list_delete(names);
             list_delete(values);
         }
@@ -375,6 +424,8 @@ config_dump(struct config_chansrv *config)
     g_writeln("    FileMask:                  0%o", config->file_umask);
     g_writeln("    Nautilus 3 Flist Format:   %s",
               g_bool2text(config->use_nautilus3_flist_format));
+    g_writeln("    LogFilePath            :   %s",
+              (config->log_file_path[0]) ? config->log_file_path : "<default>");
 }
 
 /******************************************************************************/
@@ -385,6 +436,7 @@ config_free(struct config_chansrv *cc)
     {
         g_free(cc->listen_port);
         g_free(cc->fuse_mount_name);
+        g_free(cc->log_file_path);
         g_free(cc);
     }
 }

sesman/chansrv/chansrv_config.h

@@ -50,6 +50,9 @@ struct config_chansrv
     unsigned int num_silent_frames_mp3;
     /** Do net send sound data afer SNDC_CLOSE is sent. unit is millisecond, setting from sesman.ini */
     unsigned int msec_do_not_send;
+
+    /** LogFilePath from sesman.ini ([ChansrvLogging]) */
+    char *log_file_path;
 };
 
 

sesman/sesman.ini.in

@@ -204,6 +204,11 @@ EnableSyslog=true
 #EnableConsole=false
 #ConsoleLevel=INFO
 #EnableProcessId=false
+; Log file path
+; Set this to move the log file away from its default location. You may want
+; to do this for (e.g.) NFS-mounted home directories
+; See sesman.ini(5) for the format of this parameter
+#LogFilePath=/run/user/%u/xrdp
 
 [ChansrvLoggingPerLogger]
 ; Note: per logger configuration is only used if xrdp is built with