Subversion Repositories SvarDOS

/* This file is part of the SvarCOM project and is published under the terms

 * of the MIT license.

 *

 * Copyright (C) 2021-2022 Mateusz Viste

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

 * DEALINGS IN THE SOFTWARE.

 */

/*

 * FOR %variable IN (set) DO command [command-parameters]

 *

 * %variable    a replaceable parameter name

 * (set)        a set of one of more files. Wildcards allowed.

 * command      the command to carry out for each matched file

 * command-parameters   parameters or switches for the specified command

 *

 * To use FOR in a batch program, use %%variable instead of %variable

 *

 * the set of files must be surrounded by parenthesis, and may contain one

 * or more space-delimited wildcards. Examples:

 * (file.txt other.txt)

 * (*.exe *.com *.bat)

 * (jan*.txt 199201??.txt)

 */

/* Implementation notes:

 *

 * For cannot be nested (no "FOR ... do FOR ..." allowed)

 *

 * When executed, FOR allocates a "FOR context" to RMOD's memory, this context

 * holds the memory state of a FindNext iteration, as well as the command

 * to run on each matched file.

 *

 * This FOR context is looked at by command.c and used to provide a command

 * instead of getting the command from interactive cli or BAT file. Repeats

 * until the FindNext buffer stops matching files.

 *

 * This file only provides the help screen of FOR, as well as the FOR-context

 * initialization. Actual execution happens within command.c.

 */

/* normalizing for-loop pattern-list separators.

 * returns a space char if c is a for-pattern separator, c otherwise */

static char cmd_for_sepnorm(char c) {

  /* the list of valid delimiters has been researched and kindly shared by Robert

   * Riebisch via the ticket at https://osdn.net/projects/svardos/ticket/44058 */

  switch (c) {

    case ' ':

    case '\t':

    case ';':

    case ',':

    case '/':

    case '=':

      return(' '); /* normalize FOR-loop separators to a space */

    default: /* anything else is kept as-is */

      return(c);

  }

}

static enum cmd_result cmd_for(struct cmd_funcparam *p) {

  struct forctx *f = (void *)(p->BUFFER);

  unsigned short i;

  /* forbid nested FORs */

  if (p->rmod->forloop) {

    nls_outputnl(18,7); /* "FOR cannot be nested" */

    return(CMD_FAIL);

  }

  /* help screen ONLY if /? is the only argument */

  if ((p->argc == 1) && (imatch(p->argv[0], "/?"))) {

    nls_outputnl(18,0); /* "Runs a specified command for each element in a list." */

    outputnl("");

    nls_outputnl(18,1); /* "FOR %variable IN (list) DO command [parameters]" */

    outputnl("");

    nls_outputnl(18,2); /* "%variable   Single-letter variable (a-z or A-Z)." */

    nls_outputnl(18,3); /* "(list)      One or more space-separated strings or filename wildcards." */

    nls_outputnl(18,4); /* "command     The command to carry out for each element. %variable allowed." */

    nls_outputnl(18,5); /* "parameters  Parameters or switches for the specified command." */

    outputnl("");

    nls_outputnl(18,6); /* "To use FOR in a batch program, use %%variable instead of %variable" */

    return(CMD_OK);

  }

  /* clear out struct and copy command line to it */

  bzero(f, sizeof(*f));

  strcpy(f->cmd, p->cmdline);

  /* locate the %varname (single char) */

  i = p->argoffset;

  while (f->cmd[i] == ' ') i++;

  if ((f->cmd[i] != '%') || (f->cmd[i+1] == ' ') || (f->cmd[i+2] != ' ')) goto INVALID_SYNTAX;

  f->varname = f->cmd[i+1];

  i += 3;

  /* look (and skip) the "IN" part */

  while (f->cmd[i] == ' ') i++;

  if (((f->cmd[i] & 0xDF) != 'I') && ((f->cmd[i+1] & 0xDF) != 'N') && (f->cmd[i+2] != ' ')) goto INVALID_SYNTAX;

  i += 3;

  /* look for patterns start */

  while (f->cmd[i] == ' ') i++;

  if (f->cmd[i] != '(') goto INVALID_SYNTAX;

  i++;

  while (cmd_for_sepnorm(f->cmd[i]) == ' ') i++;

  f->nextpat = i;

  /* look for patterns end and normalize all separators to a space */

  while ((f->cmd[i] != ')') && (f->cmd[i] != 0)) {

    f->cmd[i] = cmd_for_sepnorm(f->cmd[i]);

    i++;

  }

  if (f->cmd[i] != ')') goto INVALID_SYNTAX;

  f->cmd[i++] = 0; /* terminate patterns and move to next field */

  /* look (and skip) the "DO" part */

  while (f->cmd[i] == ' ') i++;

  if (((f->cmd[i] & 0xDF) != 'D') && ((f->cmd[i+1] & 0xDF) != 'O') && (f->cmd[i+2] != ' ')) goto INVALID_SYNTAX;

  i += 3;

  while (f->cmd[i] == ' ') i++;

  /* rest is the exec string */

  f->exec = i;

  /* alloc memory for the forctx context and copy f to it */

  p->rmod->forloop = rmod_fcalloc(sizeof(*f), p->rmod->rmodseg, "SVFORCTX");

  if (p->rmod->forloop == NULL) {

    nls_outputnl_doserr(8);

    return(CMD_FAIL);

  }

  _fmemcpy(p->rmod->forloop, f, sizeof(*f));

  return(CMD_OK);

  INVALID_SYNTAX:

  nls_outputnl(0,1); /* "Invalid syntax" */

  return(CMD_FAIL);

}