Fossil

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 nochangeFlag;     /* -n or --nochange.  Do a dry run */
  int verboseFlag;      /* -v or --verbose.  Output extra information */
  int debugFlag;        /* --debug option */
  int nChng;            /* Number of file renames */
  int *aChng;           /* Array of file renames */
  int i;                /* Loop counter */

  url_proxy_options();
  latestFlag = find_option("latest",0, 0)!=0;
  nochangeFlag = find_option("nochange","n",0)!=0;
  verboseFlag = find_option("verbose","v",0)!=0;
  debugFlag = find_option("debug",0,0)!=0;
  db_must_be_within_tree();
  vid = db_lget_int("checkout", 0);
  if( vid==0 ){
    fossil_fatal("cannot find current version");
  }
  if( !nochangeFlag && db_exists("SELECT 1 FROM vmerge") ){
    fossil_fatal("cannot update an uncommitted merge");

        fossil_fatal("no such version: %s", g.argv[2]);
      }else if( !is_a_version(tid) ){
        fossil_fatal("no such version: %s", g.argv[2]);
      }
    }
  }
  
  /* If no VERSION is specified on the command-line, then look for a
  ** descendent of the current version.  If there are multiple descendents,
  ** look for one from the same branch as the current version.  If there
  ** are still multiple descendents, show them all and refuse to update
  ** until the user selects one.
  */
  if( tid==0 ){
    int closeCode = 1;
    compute_leaves(vid, closeCode);
    if( !db_exists("SELECT 1 FROM leaves") ){
      closeCode = 0;
      compute_leaves(vid, closeCode);
    }

    "DROP TABLE IF EXISTS fv;"
    "CREATE TEMP TABLE fv("
    "  fn TEXT 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 */
    "  ridv INTEGER,"             /* Record ID for current version */
    "  ridt INTEGER,"             /* Record ID for target */
    "  fnt TEXT"                  /* Filename of same file on target version */
    ");"
  );

  /* Add files found in the current version
  */
  db_multi_exec(
    "INSERT OR IGNORE INTO fv(fn,fnt,idv,idt,ridv,ridt,chnged)"
    " SELECT pathname, pathname, id, 0, rid, 0, chnged FROM vfile WHERE vid=%d",
    vid
  );

  /* Compute file name changes on V->T.  Record name changes in files that
  ** have changed locally.
  */
  find_filename_changes(vid, tid, &nChng, &aChng);
  if( nChng ){
    for(i=0; i<nChng; i++){
      db_multi_exec(
        "UPDATE fv"
        "   SET fnt=(SELECT name FROM filename WHERE fnid=%d)"
        " WHERE fn=(SELECT name FROM filename WHERE fnid=%d) AND chnged",
        aChng[i*2+1], aChng[i*2]
      );
    }
    fossil_free(aChng);
  }

  /* 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,chnged)"
    " SELECT pathname, pathname, 0, 0, 0, 0, 0 FROM vfile"



    "  WHERE vid=%d"
    "    AND pathname NOT IN (SELECT fnt FROM fv)",
    tid
  );

  /*
  ** Compute the file version ids for T
  */

  db_multi_exec(
    "UPDATE fv SET"
    " idt=coalesce((SELECT id FROM vfile WHERE vid=%d AND pathname=fnt),0),"
    " ridt=coalesce((SELECT rid FROM vfile WHERE vid=%d AND pathname=fnt),0)",
    tid, tid
  );


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

    );
    while( db_step(&q)==SQLITE_ROW ){
       printf("%3d: ridv=%-4d ridt=%-4d chnged=%d\n",
          db_column_int(&q, 0),
          db_column_int(&q, 4),
          db_column_int(&q, 5),
          db_column_int(&q, 3));

       printf("     fnv = [%s]\n", db_column_text(&q, 1));
       printf("     fnt = [%s]\n", db_column_text(&q, 2));

    }
    db_finalize(&q);
  }

  /* If FILES appear on the command-line, remove from the "fv" table
  ** every entry that is not named on the command-line or which is not
  ** in a directory named on the command-line.
  */
  if( g.argc>=4 ){
    Blob sql;              /* SQL statement to purge unwanted entries */

      zSep = "AND ";
      blob_reset(&treename);
    }
    db_multi_exec(blob_str(&sql));
    blob_reset(&sql);
  }

  /*
  ** Alter the content of the checkout so that it conforms with the
  ** target
  */
  db_prepare(&q, 
    "SELECT fn, idv, ridv, idt, ridt, chnged, fnt FROM fv ORDER BY 1"
  );
  assert( g.zLocalRoot!=0 );
  assert( strlen(g.zLocalRoot)>1 );
  assert( g.zLocalRoot[strlen(g.zLocalRoot)-1]=='/' );
  while( db_step(&q)==SQLITE_ROW ){
    const char *zName = db_column_text(&q, 0);  /* The filename from root */
    int idv = db_column_int(&q, 1);             /* VFILE entry for current */
    int ridv = db_column_int(&q, 2);            /* RecordID for current */
    int idt = db_column_int(&q, 3);             /* VFILE entry for target */
    int ridt = db_column_int(&q, 4);            /* RecordID for target */
    int chnged = db_column_int(&q, 5);          /* Current is edited */
    const char *zNewName = db_column_text(&q,6);/* New filename */
    char *zFullPath;                            /* Full pathname of the file */
    char *zFullNewPath;                         /* Full pathname of dest */
    char nameChng;                              /* True if the name changed */

    zFullPath = mprintf("%s%s", g.zLocalRoot, zName);
    zFullNewPath = mprintf("%s%s", g.zLocalRoot, zNewName);
    nameChng = strcmp(zName, zNewName);
    if( idv>0 && ridv==0 && idt>0 && ridt>0 ){
      /* Conflict.  This file has been added to the current checkout
      ** but also exists in the target checkout.  Use the current version.
      */
      printf("CONFLICT %s\n", zName);
    }else if( idt>0 && idv==0 ){
      /* File added in the target. */
      printf("ADD %s\n", zName);
      undo_save(zName);
      if( !nochangeFlag ) vfile_to_disk(0, idt, 0, 0);
    }else if( idt>0 && idv>0 && ridt!=ridv && chnged==0 ){
      /* The file is unedited.  Change it to the target version */

      undo_save(zName);
      printf("UPDATE %s\n", zName);
      if( !nochangeFlag ) vfile_to_disk(0, idt, 0, 0);
    }else if( idt>0 && idv>0 && file_size(zFullPath)<0 ){
      /* The file missing from the local check-out. Restore it to the
      ** version that appears in the target. */
      printf("UPDATE %s\n", zName);
      undo_save(zName);
      if( !nochangeFlag ) 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. */
        printf("CONFLICT %s\n", zName);
      }else{

        printf("REMOVE %s\n", zName);
        undo_save(zName);

        if( !nochangeFlag ) unlink(zFullPath);

      }
    }else if( idt>0 && idv>0 && ridt!=ridv && chnged ){
      /* Merge the changes in the current tree into the target version */
      Blob e, r, t, v;
      int rc;
      if( nameChng ){
        printf("MERGE %s -> %s\n", zName, zNewName);
      }else{
        printf("MERGE %s\n", zName);
      }
      undo_save(zName);
      content_get(ridt, &t);
      content_get(ridv, &v);
      blob_zero(&e);
      blob_read_from_file(&e, zFullPath);
      rc = blob_merge(&v, &e, &t, &r);
      if( rc>=0 ){
        if( !nochangeFlag ) blob_write_to_file(&r, zFullNewPath);
        if( rc>0 ){
          printf("***** %d merge conflicts in %s\n", rc, zNewName);
        }
      }else{
        if( !nochangeFlag ) blob_write_to_file(&t, zFullNewPath);
        printf("***** Cannot merge binary file %s\n", zNewName);
      }
      if( nameChng && !nochangeFlag ) unlink(zFullPath);
      blob_reset(&v);
      blob_reset(&e);
      blob_reset(&t);
      blob_reset(&r);
    }else if( verboseFlag ){
      if( chnged ){
        printf("EDITED %s\n", zName);
      }else{
        printf("UNCHANGED %s\n", zName);
      }
    }
    free(zFullPath);
    free(zFullNewPath);
  }
  db_finalize(&q);
  printf("--------------\n");
  show_common_info(tid, "updated-to:", 1, 0);
  
  /*
  ** Clean up the mid and pid VFILE entries.  Then commit the changes.