Fossil

**
** If one or more FILES are listed after the VERSION then only the
** named files are candidates to be updated.  If FILES is omitted, all
** files in the current checkout are subject to be updated.  Using
** a directory name for one of the FILES arguments is the same as
** using every subdirectory and file beneath that directory.
**
** The -n or --dry-run option causes this command to do a "dry run".  It
** prints out what would have happened but does not actually make any
** changes to the current checkout or the repository.
**
** The -v or --verbose option prints status information about unchanged
** files in addition to those file that actually do change.
**
** Options:
**   --case-sensitive <BOOL> override case-sensitive setting
**   --debug          print debug information on stdout
**   --latest         acceptable in place of VERSION, update to latest version
**   -n|--dry-run     If given, display instead of run actions
**   -v|--verbose     print status information about all files
**
** See also: revert
*/
void update_cmd(void){
  int vid;              /* Current version */
  int tid=0;            /* Target version - version we are changing to */
  Stmt q;
  int latestFlag;       /* --latest.  Pick the latest version if true */
  int dryRunFlag;       /* -n or --dry-run.  Do a dry run */
  int verboseFlag;      /* -v or --verbose.  Output extra information */
  int debugFlag;        /* --debug option */
  int setmtimeFlag;     /* --setmtime.  Set mtimes on files */
  int nChng;            /* Number of file renames */
  int *aChng;           /* Array of file renames */
  int i;                /* Loop counter */
  int nConflict = 0;    /* Number of merge conflicts */
  int nOverwrite = 0;   /* Number of unmanaged files overwritten */
  int nUpdate = 0;      /* Number of changes of any kind */
  Stmt mtimeXfer;       /* Statement to transfer mtimes */

  if( !internalUpdate ){
    undo_capture_command_line();
    url_proxy_options();
  }
  latestFlag = find_option("latest",0, 0)!=0;
  dryRunFlag = find_option("dry-run","n",0)!=0;
  if( !dryRunFlag ){
    dryRunFlag = find_option("nochange",0,0)!=0; /* deprecated */
  }
  verboseFlag = find_option("verbose","v",0)!=0;
  debugFlag = find_option("debug",0,0)!=0;
  setmtimeFlag = find_option("setmtime",0,0)!=0;
  capture_case_sensitive_option();
  db_must_be_within_tree();
  vid = db_lget_int("checkout", 0);
  if( vid==0 ){
    fossil_fatal("cannot find current version");
  }
  if( !dryRunFlag && !internalUpdate ){
    autosync(SYNC_PULL + SYNC_VERBOSE*verboseFlag);
  }
  
  /* Create any empty directories now, as well as after the update,
  ** so changes in settings are reflected now */
  if( !dryRunFlag ) ensure_empty_dirs_created();

  if( internalUpdate ){
    tid = internalUpdate;
  }else if( g.argc>=3 ){
    if( fossil_strcmp(g.argv[2], "current")==0 ){
      /* If VERSION is "current", then use the same algorithm to find the
      ** target as if VERSION were omitted. */

  if( tid==0 ){
    fossil_panic("Internal Error: unable to find a version to update to.");
  }

  db_begin_transaction();
  vfile_check_signature(vid, CKSIG_ENOTFILE);
  if( !dryRunFlag && !internalUpdate ) undo_begin();
  load_vfile_from_rid(tid);

  /*
  ** The record.fn field is used to match files against each other.  The
  ** FV table contains one row for each each unique filename in
  ** in the current checkout, the pivot, and the version being merged.
  */
  db_multi_exec(
    "DROP TABLE IF EXISTS fv;"
    "CREATE TEMP TABLE fv("
    "  fn TEXT %s PRIMARY KEY,"   /* The filename relative to root */
    "  idv INTEGER,"              /* VFILE entry for current version */
    "  idt INTEGER,"              /* VFILE entry for target version */
    "  chnged BOOLEAN,"           /* True if current version has been edited */
    "  islinkv BOOLEAN,"          /* True if current file is a link */
    "  islinkt BOOLEAN,"          /* True if target file is a link */
    "  ridv INTEGER,"             /* Record ID for current version */
    "  ridt INTEGER,"             /* Record ID for target */
    "  isexe BOOLEAN,"            /* Does target have execute permission? */
    "  deleted BOOLEAN DEFAULT 0,"/* File marke by "rm" to become unmanaged */
    "  fnt TEXT %s"               /* Filename of same file on target version */
    ");",
    filename_collation(), filename_collation()
  );

  /* Add files found in the current version
  */
  db_multi_exec(
    "INSERT OR IGNORE INTO fv(fn,fnt,idv,idt,ridv,ridt,isexe,chnged,deleted)"
    " SELECT pathname, pathname, id, 0, rid, 0, isexe, chnged, deleted"

  /* Add files found in the target version T but missing from the current
  ** version V.
  */
  db_multi_exec(
    "INSERT OR IGNORE INTO fv(fn,fnt,idv,idt,ridv,ridt,isexe,chnged)"
    " SELECT pathname, pathname, 0, 0, 0, 0, isexe, 0 FROM vfile"
    "  WHERE vid=%d"
    "    AND pathname %s NOT IN (SELECT fnt FROM fv)",
    tid, filename_collation()
  );

  /*
  ** Compute the file version ids for T
  */
  db_multi_exec(
    "UPDATE fv SET"
    " idt=coalesce((SELECT id FROM vfile WHERE vid=%d AND fnt=pathname),0),"
    " ridt=coalesce((SELECT rid FROM vfile WHERE vid=%d AND fnt=pathname),0)",
    tid, tid
  );

  /*
  ** Add islink information
  */
  db_multi_exec(
    "UPDATE fv SET"
    " islinkv=coalesce((SELECT islink FROM vfile"
                       " WHERE vid=%d AND fnt=pathname),0),"
    " islinkt=coalesce((SELECT islink FROM vfile"
                       " WHERE vid=%d AND fnt=pathname),0)",
    vid, tid
  );


  if( debugFlag ){
    db_prepare(&q,
       "SELECT rowid, fn, fnt, chnged, ridv, ridt, isexe,"

      if( file_wd_isfile_or_link(zFullPath) ){
        fossil_print("ADD %s - overwrites an unmanaged file\n", zName);
        nOverwrite++;
      }else{
        fossil_print("ADD %s\n", zName);
      }
      undo_save(zName);
      if( !dryRunFlag ) vfile_to_disk(0, idt, 0, 0);
    }else if( idt>0 && idv>0 && ridt!=ridv && (chnged==0 || deleted) ){
      /* The file is unedited.  Change it to the target version */
      undo_save(zName);
      if( deleted ){
        fossil_print("UPDATE %s - change to unmanged file\n", zName);
      }else{
        fossil_print("UPDATE %s\n", zName);
      }
      if( !dryRunFlag ) vfile_to_disk(0, idt, 0, 0);
    }else if( idt>0 && idv>0 && file_wd_size(zFullPath)<0 ){
      /* The file missing from the local check-out. Restore it to the
      ** version that appears in the target. */
      fossil_print("UPDATE %s%s\n", zName,
                    deleted?" - change to unmanaged file":"");
      undo_save(zName);
      if( !dryRunFlag ) vfile_to_disk(0, idt, 0, 0);
    }else if( idt==0 && idv>0 ){
      if( ridv==0 ){
        /* Added in current checkout.  Continue to hold the file as
        ** as an addition */
        db_multi_exec("UPDATE vfile SET vid=%d WHERE id=%d", tid, idv);
      }else if( chnged ){
        /* Edited locally but deleted from the target.  Do not track the
        ** file but keep the edited version around. */
        fossil_print("CONFLICT %s - edited locally but deleted by update\n",
                     zName);
        nConflict++;
      }else{
        fossil_print("REMOVE %s\n", zName);
        undo_save(zName);
        if( !dryRunFlag ) file_delete(zFullPath);
      }
    }else if( idt>0 && idv>0 && ridt!=ridv && chnged ){
      /* Merge the changes in the current tree into the target version */
      Blob r, t, v;
      int rc;
      if( nameChng ){
        fossil_print("MERGE %s -> %s\n", zName, zNewName);
      }else{
        fossil_print("MERGE %s\n", zName);
      }
      if( islinkv || islinkt /* || file_wd_islink(zFullPath) */ ){
        fossil_print("***** Cannot merge symlink %s\n", zNewName);
        nConflict++;        
      }else{
        unsigned mergeFlags = dryRunFlag ? MERGE_DRYRUN : 0;
        undo_save(zName);
        content_get(ridt, &t);
        content_get(ridv, &v);
        rc = merge_3way(&v, zFullPath, &t, &r, mergeFlags);
        if( rc>=0 ){
          if( !dryRunFlag ){
            blob_write_to_file(&r, zFullNewPath);
            file_wd_setexe(zFullNewPath, isexe);
          }
          if( rc>0 ){
            fossil_print("***** %d merge conflicts in %s\n", rc, zNewName);
            nConflict++;
          }
        }else{
          if( !dryRunFlag ){
            blob_write_to_file(&t, zFullNewPath);
            file_wd_setexe(zFullNewPath, isexe);
          }
          fossil_print("***** Cannot merge binary file %s\n", zNewName);
          nConflict++;
        }
      }
      if( nameChng && !dryRunFlag ) file_delete(zFullPath);
      blob_reset(&v);
      blob_reset(&t);
      blob_reset(&r);
    }else{
      nUpdate--;
      if( chnged ){
        if( verboseFlag ) fossil_print("EDITED %s\n", zName);

    show_common_info(tid, "updated-to:", 1, 0);
    fossil_print("%-13s %d file%s modified.\n", "changes:",
                 nUpdate, nUpdate>1 ? "s" : "");
  }

  /* Report on conflicts
  */
  if( !dryRunFlag ){
    Stmt q;
    int nMerge = 0;
    db_prepare(&q, "SELECT uuid, id FROM vmerge JOIN blob ON merge=rid"
                   " WHERE id<=0");
    while( db_step(&q)==SQLITE_ROW ){
      const char *zLabel = "merge";
      switch( db_column_int(&q, 1) ){

      fossil_warning("WARNING: %d uncommitted prior merges", nMerge);
    }
  }
  
  /*
  ** Clean up the mid and pid VFILE entries.  Then commit the changes.
  */
  if( dryRunFlag ){
    db_end_transaction(1);  /* With --dry-run, rollback changes */
  }else{
    ensure_empty_dirs_created();
    if( g.argc<=3 ){
      /* All files updated.  Shift the current checkout to the target. */
      db_multi_exec("DELETE FROM vfile WHERE vid!=%d", tid);
      checkout_set_all_exe(tid);
      manifest_to_disk(tid);