src/command.c

   1 /*
   2     psh/command.c - psh commands
   3     Copyright 2020 Zhang Maiyun
   4
   5     This file is part of Psh, P shell.
   6
   7     Psh is free software: you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation, either version 3 of the License, or
  10     (at your option) any later version.
  11
  12     Psh is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19 */
  20
  21 #ifdef HAVE_CONFIG_H
  22 #include "config.h"
  23 #endif
  24
  25 #include <string.h>
  26
  27 #include "command.h"
  28 #include "libpsh/xmalloc.h"
  29
  30 void free_redirect(struct _psh_redirect *redir)
  31 {
  32     struct _psh_redirect *temp;
  33     while (redir != NULL)
  34     {
  35         temp = redir;
  36         redir = redir->next;
  37         xfree(temp);
  38         temp = NULL;
  39     }
  40 }
  41
  42 /* Malloc a command, enNULL all elements, malloc the first element in argv[] and
  43  * a struct _psh_redirect */
  44 struct _psh_command *new_command()
  45 {
  46     /* TODO: Remove MAXARG, MAXEACHARG */
  47     struct _psh_command *cmd;
  48     cmd = xcalloc(1, sizeof(struct _psh_command));
  49     /* Setting to '\0' will be used to detect
  50                            whether an element is used */
  51     cmd->argv = xcalloc(MAXARG, P_CS);
  52     cmd->argv[0] = xcalloc(MAXEACHARG, P_CS);
  53     cmd->rlist = xcalloc(1, sizeof(struct _psh_redirect));
  54     return cmd;
  55 }
  56
  57 /* Free a command and its nexts */
  58 void free_command(struct _psh_command *cmd)
  59 {
  60     struct _psh_command *temp;
  61     while (cmd != NULL)
  62     {
  63         temp = cmd;
  64         cmd = cmd->next;
  65         free_argv(temp);
  66         free_redirect(temp->rlist);
  67         xfree(temp);
  68         temp = NULL;
  69     }
  70 }
  71
  72 void free_argv(struct _psh_command *cmd)
  73 {
  74     int count;
  75     for (count = 0; count < MAXARG; ++count)
  76     {
  77         if (cmd->argv[count] == NULL)
  78             break; /* All args should be freed after here */
  79         xfree(cmd->argv[count]);
  80         cmd->argv[count] = NULL;
  81     }
  82     xfree(cmd->argv);
  83     cmd->argv = NULL;
  84 }