CLI: Add force option when creating a symlink. This will allow to overwrite an already defined symlink

Closes EOS-6392

Author: gmgigi96

console/commands/com_file.cc

@@ -308,6 +308,10 @@ com_file(char* arg1)
     in += path.c_str();
     in += "&mgm.file.target=";
     in += fsid1.c_str();
+
+    if (option.find("f") != STR_NPOS) {
+      in +=  "&mgm.file.force=1";
+    }
   }
 
   if (cmd == "share") {
@@ -1123,9 +1127,12 @@ com_file(char* arg1)
           "file replicate [<path>|fid:<fid-dec>|fxid:<fid-hex>] <fsid1> <fsid2> :\n");
   fprintf(stdout,
           "                                                  replicate file <path> part on <fsid1> to <fsid2>\n");
-  fprintf(stdout, "file symlink <name> <link-name> :\n");
+  fprintf(stdout,
+          "file symlink [-f] <name> <link-name> :\n");
   fprintf(stdout,
           "                                                  create a symlink with <name> pointing to <link-name>\n");
+  fprintf(stdout,
+          "         -f                                                            :  force overwrite\n");
   fprintf(stdout, "file tag <path>|fid:<fid-dec>|fxid:<fid-hex> +|-|~<fsid> :\n");
   fprintf(stdout,
           "                                                  add/remove/unlink a filesystem location to/from a file in the location index - attention this does not move any data!\n");

mgm/XrdMgmOfs.hh

@@ -673,7 +673,8 @@ public:
               XrdOucErrInfo& out_error,
               const XrdSecEntity* client = 0,
               const char* opaqueO = 0,
-              const char* opaqueN = 0);
+              const char* opaqueN = 0,
+              bool overwrite = false);
 
   // ---------------------------------------------------------------------------
   // symlink file/dir by vid
@@ -694,7 +695,8 @@ public:
                XrdOucErrInfo& out_error,
                eos::common::VirtualIdentity& vid,
                const char* opaqueO = 0,
-               const char* opaqueN = 0);
+               const char* opaqueN = 0,
+               bool overwrite = false);
 
   // ---------------------------------------------------------------------------
   // read symbolic link

mgm/XrdMgmOfs/Link.cc

@@ -34,7 +34,8 @@ XrdMgmOfs::symlink(const char* source_name,
                    XrdOucErrInfo& error,
                    const XrdSecEntity* client,
                    const char* infoO,
-                   const char* infoN)
+                   const char* infoN,
+                   bool overwrite)
 /*----------------------------------------------------------------------------*/
 /*
  * @brief symlink a file or directory
@@ -100,7 +101,7 @@ XrdMgmOfs::symlink(const char* source_name,
     MAYREDIRECT;
   }
   return symlink(sourcen.c_str(), targetn.c_str(), error, vid, infoO, infoN,
-                 true);
+                 overwrite);
 }
 
 /*----------------------------------------------------------------------------*/
@@ -157,7 +158,8 @@ XrdMgmOfs::symlink(const char* source_name,
     return SFS_ERROR;
   }
 
-  return _symlink(sourcen.c_str(), targetn.c_str(), error, vid, infoO, infoN);
+  return _symlink(sourcen.c_str(), targetn.c_str(), error, vid, infoO, infoN,
+                  overwrite);
 }
 
 /*----------------------------------------------------------------------------*/
@@ -167,7 +169,8 @@ XrdMgmOfs::_symlink(const char* source_name,
                     XrdOucErrInfo& error,
                     eos::common::VirtualIdentity& vid,
                     const char* infoO,
-                    const char* infoN
+                    const char* infoN,
+                    bool overwrite
                    )
 /*----------------------------------------------------------------------------*/
 /*
@@ -216,8 +219,12 @@ XrdMgmOfs::_symlink(const char* source_name,
   _exists(source_name, file_exists, error, vid, infoN);
 
   if (file_exists != XrdSfsFileExistNo) {
-    errno = EEXIST;
-    return Emsg(epname, error, ENOENT, "symlink - source exists");
+    if (overwrite) {
+      _rem(source_name, error, vid, infoO);
+    } else {
+      errno = EEXIST;
+      return Emsg(epname, error, ENOENT, "symlink - source exists");
+    }
   }
 
   {

mgm/proc/user/File.cc

@@ -629,8 +629,12 @@ ProcCommand::File()
       cmdok = true;
       XrdOucString source = pOpaque->Get("mgm.file.source");
       XrdOucString target = pOpaque->Get("mgm.file.target");
+      XrdOucString forceS = pOpaque->Get("mgm.file.force");
+      const char* cc = forceS.c_str();
+      bool force = forceS == "1";
 
-      if (gOFS->symlink(source.c_str(), target.c_str(), *mError, *pVid, 0, 0, true)) {
+      if (gOFS->symlink(source.c_str(), target.c_str(), *mError, *pVid, 0, 0,
+                        force)) {
         stdErr += "error: unable to link";
         retc = errno;
       } else {