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+/* make_cmd.c -- Functions for making instances of the various
+ parser constructs. */
+
+/* Copyright (C) 1989-2005 Free Software Foundation, Inc.
+
+This file is part of GNU Bash, the Bourne Again SHell.
+
+Bash is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Bash is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License along
+with Bash; see the file COPYING. If not, write to the Free Software
+Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
+
+#include "config.h"
+
+#include <stdio.h>
+#include "bashtypes.h"
+#if !defined (_MINIX) && defined (HAVE_SYS_FILE_H)
+# include <sys/file.h>
+#endif
+#include "filecntl.h"
+#include "bashansi.h"
+#if defined (HAVE_UNISTD_H)
+# include <unistd.h>
+#endif
+
+#include "bashintl.h"
+
+#include "syntax.h"
+#include "command.h"
+#include "general.h"
+#include "error.h"
+#include "flags.h"
+#include "make_cmd.h"
+#include "dispose_cmd.h"
+#include "variables.h"
+#include "subst.h"
+#include "input.h"
+#include "ocache.h"
+#include "externs.h"
+
+#if defined (JOB_CONTROL)
+#include "jobs.h"
+#endif
+
+#include "shmbutil.h"
+
+extern int line_number, current_command_line_count;
+extern int last_command_exit_value;
+
+/* Object caching */
+sh_obj_cache_t wdcache = {0, 0, 0};
+sh_obj_cache_t wlcache = {0, 0, 0};
+
+#define WDCACHESIZE 60
+#define WLCACHESIZE 60
+
+static COMMAND *make_for_or_select __P((enum command_type, WORD_DESC *, WORD_LIST *, COMMAND *, int));
+#if defined (ARITH_FOR_COMMAND)
+static WORD_LIST *make_arith_for_expr __P((char *));
+#endif
+static COMMAND *make_until_or_while __P((enum command_type, COMMAND *, COMMAND *));
+
+void
+cmd_init ()
+{
+ ocache_create (wdcache, WORD_DESC, WDCACHESIZE);
+ ocache_create (wlcache, WORD_LIST, WLCACHESIZE);
+}
+
+WORD_DESC *
+alloc_word_desc ()
+{
+ WORD_DESC *temp;
+
+ ocache_alloc (wdcache, WORD_DESC, temp);
+ temp->flags = 0;
+ temp->word = 0;
+ return temp;
+}
+
+WORD_DESC *
+make_bare_word (string)
+ const char *string;
+{
+ WORD_DESC *temp;
+
+ temp = alloc_word_desc ();
+
+ if (*string)
+ temp->word = savestring (string);
+ else
+ {
+ temp->word = (char *)xmalloc (1);
+ temp->word[0] = '\0';
+ }
+
+ return (temp);
+}
+
+WORD_DESC *
+make_word_flags (w, string)
+ WORD_DESC *w;
+ const char *string;
+{
+ register int i;
+ size_t slen;
+ DECLARE_MBSTATE;
+
+ i = 0;
+ slen = strlen (string);
+ while (i < slen)
+ {
+ switch (string[i])
+ {
+ case '$':
+ w->flags |= W_HASDOLLAR;
+ break;
+ case '\\':
+ break; /* continue the loop */
+ case '\'':
+ case '`':
+ case '"':
+ w->flags |= W_QUOTED;
+ break;
+ }
+
+ ADVANCE_CHAR (string, slen, i);
+ }
+
+ return (w);
+}
+
+WORD_DESC *
+make_word (string)
+ const char *string;
+{
+ WORD_DESC *temp;
+
+ temp = make_bare_word (string);
+ return (make_word_flags (temp, string));
+}
+
+WORD_DESC *
+make_word_from_token (token)
+ int token;
+{
+ char tokenizer[2];
+
+ tokenizer[0] = token;
+ tokenizer[1] = '\0';
+
+ return (make_word (tokenizer));
+}
+
+WORD_LIST *
+make_word_list (word, wlink)
+ WORD_DESC *word;
+ WORD_LIST *wlink;
+{
+ WORD_LIST *temp;
+
+ ocache_alloc (wlcache, WORD_LIST, temp);
+
+ temp->word = word;
+ temp->next = wlink;
+ return (temp);
+}
+
+COMMAND *
+make_command (type, pointer)
+ enum command_type type;
+ SIMPLE_COM *pointer;
+{
+ COMMAND *temp;
+
+ temp = (COMMAND *)xmalloc (sizeof (COMMAND));
+ temp->type = type;
+ temp->value.Simple = pointer;
+ temp->value.Simple->flags = temp->flags = 0;
+ temp->redirects = (REDIRECT *)NULL;
+ return (temp);
+}
+
+COMMAND *
+command_connect (com1, com2, connector)
+ COMMAND *com1, *com2;
+ int connector;
+{
+ CONNECTION *temp;
+
+ temp = (CONNECTION *)xmalloc (sizeof (CONNECTION));
+ temp->connector = connector;
+ temp->first = com1;
+ temp->second = com2;
+ return (make_command (cm_connection, (SIMPLE_COM *)temp));
+}
+
+static COMMAND *
+make_for_or_select (type, name, map_list, action, lineno)
+ enum command_type type;
+ WORD_DESC *name;
+ WORD_LIST *map_list;
+ COMMAND *action;
+ int lineno;
+{
+ FOR_COM *temp;
+
+ temp = (FOR_COM *)xmalloc (sizeof (FOR_COM));
+ temp->flags = 0;
+ temp->name = name;
+ temp->line = lineno;
+ temp->map_list = map_list;
+ temp->action = action;
+ return (make_command (type, (SIMPLE_COM *)temp));
+}
+
+COMMAND *
+make_for_command (name, map_list, action, lineno)
+ WORD_DESC *name;
+ WORD_LIST *map_list;
+ COMMAND *action;
+ int lineno;
+{
+ return (make_for_or_select (cm_for, name, map_list, action, lineno));
+}
+
+COMMAND *
+make_select_command (name, map_list, action, lineno)
+ WORD_DESC *name;
+ WORD_LIST *map_list;
+ COMMAND *action;
+ int lineno;
+{
+#if defined (SELECT_COMMAND)
+ return (make_for_or_select (cm_select, name, map_list, action, lineno));
+#else
+ last_command_exit_value = 2;
+ return ((COMMAND *)NULL);
+#endif
+}
+
+#if defined (ARITH_FOR_COMMAND)
+static WORD_LIST *
+make_arith_for_expr (s)
+ char *s;
+{
+ WORD_LIST *result;
+ WORD_DESC *wd;
+
+ if (s == 0 || *s == '\0')
+ return ((WORD_LIST *)NULL);
+ wd = make_word (s);
+ wd->flags |= W_NOGLOB|W_NOSPLIT|W_QUOTED|W_DQUOTE; /* no word splitting or globbing */
+ result = make_word_list (wd, (WORD_LIST *)NULL);
+ return result;
+}
+#endif
+
+/* Note that this function calls dispose_words on EXPRS, since it doesn't
+ use the word list directly. We free it here rather than at the caller
+ because no other function in this file requires that the caller free
+ any arguments. */
+COMMAND *
+make_arith_for_command (exprs, action, lineno)
+ WORD_LIST *exprs;
+ COMMAND *action;
+ int lineno;
+{
+#if defined (ARITH_FOR_COMMAND)
+ ARITH_FOR_COM *temp;
+ WORD_LIST *init, *test, *step;
+ char *s, *t, *start;
+ int nsemi;
+
+ init = test = step = (WORD_LIST *)NULL;
+ /* Parse the string into the three component sub-expressions. */
+ start = t = s = exprs->word->word;
+ for (nsemi = 0; ;)
+ {
+ /* skip whitespace at the start of each sub-expression. */
+ while (whitespace (*s))
+ s++;
+ start = s;
+ /* skip to the semicolon or EOS */
+ while (*s && *s != ';')
+ s++;
+
+ t = (s > start) ? substring (start, 0, s - start) : (char *)NULL;
+
+ nsemi++;
+ switch (nsemi)
+ {
+ case 1:
+ init = make_arith_for_expr (t);
+ break;
+ case 2:
+ test = make_arith_for_expr (t);
+ break;
+ case 3:
+ step = make_arith_for_expr (t);
+ break;
+ }
+
+ FREE (t);
+ if (*s == '\0')
+ break;
+ s++; /* skip over semicolon */
+ }
+
+ if (nsemi != 3)
+ {
+ if (nsemi < 3)
+ parser_error (lineno, _("syntax error: arithmetic expression required"));
+ else
+ parser_error (lineno, _("syntax error: `;' unexpected"));
+ parser_error (lineno, _("syntax error: `((%s))'"), exprs->word->word);
+ last_command_exit_value = 2;
+ return ((COMMAND *)NULL);
+ }
+
+ temp = (ARITH_FOR_COM *)xmalloc (sizeof (ARITH_FOR_COM));
+ temp->flags = 0;
+ temp->line = lineno;
+ temp->init = init ? init : make_arith_for_expr ("1");
+ temp->test = test ? test : make_arith_for_expr ("1");
+ temp->step = step ? step : make_arith_for_expr ("1");
+ temp->action = action;
+
+ dispose_words (exprs);
+ return (make_command (cm_arith_for, (SIMPLE_COM *)temp));
+#else
+ dispose_words (exprs);
+ last_command_exit_value = 2;
+ return ((COMMAND *)NULL);
+#endif /* ARITH_FOR_COMMAND */
+}
+
+COMMAND *
+make_group_command (command)
+ COMMAND *command;
+{
+ GROUP_COM *temp;
+
+ temp = (GROUP_COM *)xmalloc (sizeof (GROUP_COM));
+ temp->command = command;
+ return (make_command (cm_group, (SIMPLE_COM *)temp));
+}
+
+COMMAND *
+make_case_command (word, clauses, lineno)
+ WORD_DESC *word;
+ PATTERN_LIST *clauses;
+ int lineno;
+{
+ CASE_COM *temp;
+
+ temp = (CASE_COM *)xmalloc (sizeof (CASE_COM));
+ temp->flags = 0;
+ temp->line = lineno;
+ temp->word = word;
+ temp->clauses = REVERSE_LIST (clauses, PATTERN_LIST *);
+ return (make_command (cm_case, (SIMPLE_COM *)temp));
+}
+
+PATTERN_LIST *
+make_pattern_list (patterns, action)
+ WORD_LIST *patterns;
+ COMMAND *action;
+{
+ PATTERN_LIST *temp;
+
+ temp = (PATTERN_LIST *)xmalloc (sizeof (PATTERN_LIST));
+ temp->patterns = REVERSE_LIST (patterns, WORD_LIST *);
+ temp->action = action;
+ temp->next = NULL;
+ temp->flags = 0;
+ return (temp);
+}
+
+COMMAND *
+make_if_command (test, true_case, false_case)
+ COMMAND *test, *true_case, *false_case;
+{
+ IF_COM *temp;
+
+ temp = (IF_COM *)xmalloc (sizeof (IF_COM));
+ temp->flags = 0;
+ temp->test = test;
+ temp->true_case = true_case;
+ temp->false_case = false_case;
+ return (make_command (cm_if, (SIMPLE_COM *)temp));
+}
+
+static COMMAND *
+make_until_or_while (which, test, action)
+ enum command_type which;
+ COMMAND *test, *action;
+{
+ WHILE_COM *temp;
+
+ temp = (WHILE_COM *)xmalloc (sizeof (WHILE_COM));
+ temp->flags = 0;
+ temp->test = test;
+ temp->action = action;
+ return (make_command (which, (SIMPLE_COM *)temp));
+}
+
+COMMAND *
+make_while_command (test, action)
+ COMMAND *test, *action;
+{
+ return (make_until_or_while (cm_while, test, action));
+}
+
+COMMAND *
+make_until_command (test, action)
+ COMMAND *test, *action;
+{
+ return (make_until_or_while (cm_until, test, action));
+}
+
+COMMAND *
+make_arith_command (exp)
+ WORD_LIST *exp;
+{
+#if defined (DPAREN_ARITHMETIC)
+ COMMAND *command;
+ ARITH_COM *temp;
+
+ command = (COMMAND *)xmalloc (sizeof (COMMAND));
+ command->value.Arith = temp = (ARITH_COM *)xmalloc (sizeof (ARITH_COM));
+
+ temp->flags = 0;
+ temp->line = line_number;
+ temp->exp = exp;
+
+ command->type = cm_arith;
+ command->redirects = (REDIRECT *)NULL;
+ command->flags = 0;
+
+ return (command);
+#else
+ last_command_exit_value = 2;
+ return ((COMMAND *)NULL);
+#endif
+}
+
+#if defined (COND_COMMAND)
+struct cond_com *
+make_cond_node (type, op, left, right)
+ int type;
+ WORD_DESC *op;
+ struct cond_com *left, *right;
+{
+ COND_COM *temp;
+
+ temp = (COND_COM *)xmalloc (sizeof (COND_COM));
+ temp->flags = 0;
+ temp->line = line_number;
+ temp->type = type;
+ temp->op = op;
+ temp->left = left;
+ temp->right = right;
+
+ return (temp);
+}
+#endif
+
+COMMAND *
+make_cond_command (cond_node)
+ COND_COM *cond_node;
+{
+#if defined (COND_COMMAND)
+ COMMAND *command;
+
+ command = (COMMAND *)xmalloc (sizeof (COMMAND));
+ command->value.Cond = cond_node;
+
+ command->type = cm_cond;
+ command->redirects = (REDIRECT *)NULL;
+ command->flags = 0;
+ command->line = cond_node ? cond_node->line : 0;
+
+ return (command);
+#else
+ last_command_exit_value = 2;
+ return ((COMMAND *)NULL);
+#endif
+}
+
+COMMAND *
+make_bare_simple_command ()
+{
+ COMMAND *command;
+ SIMPLE_COM *temp;
+
+ command = (COMMAND *)xmalloc (sizeof (COMMAND));
+ command->value.Simple = temp = (SIMPLE_COM *)xmalloc (sizeof (SIMPLE_COM));
+
+ temp->flags = 0;
+ temp->line = line_number;
+ temp->words = (WORD_LIST *)NULL;
+ temp->redirects = (REDIRECT *)NULL;
+
+ command->type = cm_simple;
+ command->redirects = (REDIRECT *)NULL;
+ command->flags = 0;
+
+ return (command);
+}
+
+/* Return a command which is the connection of the word or redirection
+ in ELEMENT, and the command * or NULL in COMMAND. */
+COMMAND *
+make_simple_command (element, command)
+ ELEMENT element;
+ COMMAND *command;
+{
+ /* If we are starting from scratch, then make the initial command
+ structure. Also note that we have to fill in all the slots, since
+ malloc doesn't return zeroed space. */
+ if (!command)
+ command = make_bare_simple_command ();
+
+ if (element.word)
+ command->value.Simple->words = make_word_list (element.word, command->value.Simple->words);
+ else if (element.redirect)
+ {
+ REDIRECT *r = element.redirect;
+ /* Due to the way <> is implemented, there may be more than a single
+ redirection in element.redirect. We just follow the chain as far
+ as it goes, and hook onto the end. */
+ while (r->next)
+ r = r->next;
+ r->next = command->value.Simple->redirects;
+ command->value.Simple->redirects = element.redirect;
+ }
+ return (command);
+}
+
+/* Because we are Bourne compatible, we read the input for this
+ << or <<- redirection now, from wherever input is coming from.
+ We store the input read into a WORD_DESC. Replace the text of
+ the redirectee.word with the new input text. If <<- is on,
+ then remove leading TABS from each line. */
+void
+make_here_document (temp)
+ REDIRECT *temp;
+{
+ int kill_leading, redir_len;
+ char *redir_word, *document, *full_line;
+ int document_index, document_size, delim_unquoted;
+
+ if (temp->instruction != r_deblank_reading_until &&
+ temp->instruction != r_reading_until)
+ {
+ internal_error (_("make_here_document: bad instruction type %d"), temp->instruction);
+ return;
+ }
+
+ kill_leading = temp->instruction == r_deblank_reading_until;
+
+ document = (char *)NULL;
+ document_index = document_size = 0;
+
+ /* Quote removal is the only expansion performed on the delimiter
+ for here documents, making it an extremely special case. */
+ redir_word = string_quote_removal (temp->redirectee.filename->word, 0);
+
+ /* redirection_expand will return NULL if the expansion results in
+ multiple words or no words. Check for that here, and just abort
+ this here document if it does. */
+ if (redir_word)
+ redir_len = strlen (redir_word);
+ else
+ {
+ temp->here_doc_eof = (char *)xmalloc (1);
+ temp->here_doc_eof[0] = '\0';
+ goto document_done;
+ }
+
+ free (temp->redirectee.filename->word);
+ temp->here_doc_eof = redir_word;
+
+ /* Read lines from wherever lines are coming from.
+ For each line read, if kill_leading, then kill the
+ leading tab characters.
+ If the line matches redir_word exactly, then we have
+ manufactured the document. Otherwise, add the line to the
+ list of lines in the document. */
+
+ /* If the here-document delimiter was quoted, the lines should
+ be read verbatim from the input. If it was not quoted, we
+ need to perform backslash-quoted newline removal. */
+ delim_unquoted = (temp->redirectee.filename->flags & W_QUOTED) == 0;
+ while (full_line = read_secondary_line (delim_unquoted))
+ {
+ register char *line;
+ int len;
+
+ line = full_line;
+ line_number++;
+
+ if (kill_leading && *line)
+ {
+ /* Hack: To be compatible with some Bourne shells, we
+ check the word before stripping the whitespace. This
+ is a hack, though. */
+ if (STREQN (line, redir_word, redir_len) && line[redir_len] == '\n')
+ goto document_done;
+
+ while (*line == '\t')
+ line++;
+ }
+
+ if (*line == 0)
+ continue;
+
+ if (STREQN (line, redir_word, redir_len) && line[redir_len] == '\n')
+ goto document_done;
+
+ len = strlen (line);
+ if (len + document_index >= document_size)
+ {
+ document_size = document_size ? 2 * (document_size + len) : len + 2;
+ document = (char *)xrealloc (document, document_size);
+ }
+
+ /* len is guaranteed to be > 0 because of the check for line
+ being an empty string before the call to strlen. */
+ FASTCOPY (line, document + document_index, len);
+ document_index += len;
+ }
+
+document_done:
+ if (document)
+ document[document_index] = '\0';
+ else
+ {
+ document = (char *)xmalloc (1);
+ document[0] = '\0';
+ }
+ temp->redirectee.filename->word = document;
+}
+
+/* Generate a REDIRECT from SOURCE, DEST, and INSTRUCTION.
+ INSTRUCTION is the instruction type, SOURCE is a file descriptor,
+ and DEST is a file descriptor or a WORD_DESC *. */
+REDIRECT *
+make_redirection (source, instruction, dest_and_filename)
+ int source;
+ enum r_instruction instruction;
+ REDIRECTEE dest_and_filename;
+{
+ REDIRECT *temp;
+ WORD_DESC *w;
+ int wlen;
+ intmax_t lfd;
+
+ temp = (REDIRECT *)xmalloc (sizeof (REDIRECT));
+
+ /* First do the common cases. */
+ temp->redirector = source;
+ temp->redirectee = dest_and_filename;
+ temp->instruction = instruction;
+ temp->flags = 0;
+ temp->next = (REDIRECT *)NULL;
+
+ switch (instruction)
+ {
+
+ case r_output_direction: /* >foo */
+ case r_output_force: /* >| foo */
+ case r_err_and_out: /* command &>filename */
+ temp->flags = O_TRUNC | O_WRONLY | O_CREAT;
+ break;
+
+ case r_appending_to: /* >>foo */
+ temp->flags = O_APPEND | O_WRONLY | O_CREAT;
+ break;
+
+ case r_input_direction: /* <foo */
+ case r_inputa_direction: /* foo & makes this. */
+ temp->flags = O_RDONLY;
+ break;
+
+ case r_input_output: /* <>foo */
+ temp->flags = O_RDWR | O_CREAT;
+ break;
+
+ case r_deblank_reading_until: /* <<-foo */
+ case r_reading_until: /* << foo */
+ case r_reading_string: /* <<< foo */
+ case r_close_this: /* <&- */
+ case r_duplicating_input: /* 1<&2 */
+ case r_duplicating_output: /* 1>&2 */
+ break;
+
+ /* the parser doesn't pass these. */
+ case r_move_input: /* 1<&2- */
+ case r_move_output: /* 1>&2- */
+ case r_move_input_word: /* 1<&$foo- */
+ case r_move_output_word: /* 1>&$foo- */
+ break;
+
+ /* The way the lexer works we have to do this here. */
+ case r_duplicating_input_word: /* 1<&$foo */
+ case r_duplicating_output_word: /* 1>&$foo */
+ w = dest_and_filename.filename;
+ wlen = strlen (w->word) - 1;
+ if (w->word[wlen] == '-') /* Yuck */
+ {
+ w->word[wlen] = '\0';
+ if (all_digits (w->word) && legal_number (w->word, &lfd) && lfd == (int)lfd)
+ {
+ dispose_word (w);
+ temp->instruction = (instruction == r_duplicating_input_word) ? r_move_input : r_move_output;
+ temp->redirectee.dest = lfd;
+ }
+ else
+ temp->instruction = (instruction == r_duplicating_input_word) ? r_move_input_word : r_move_output_word;
+ }
+
+ break;
+
+ default:
+ programming_error (_("make_redirection: redirection instruction `%d' out of range"), instruction);
+ abort ();
+ break;
+ }
+ return (temp);
+}
+
+COMMAND *
+make_function_def (name, command, lineno, lstart)
+ WORD_DESC *name;
+ COMMAND *command;
+ int lineno, lstart;
+{
+ FUNCTION_DEF *temp;
+#if defined (ARRAY_VARS)
+ SHELL_VAR *bash_source_v;
+ ARRAY *bash_source_a;
+ char *t;
+#endif
+
+ temp = (FUNCTION_DEF *)xmalloc (sizeof (FUNCTION_DEF));
+ temp->command = command;
+ temp->name = name;
+ temp->line = lineno;
+ temp->flags = 0;
+ command->line = lstart;
+
+ /* Information used primarily for debugging. */
+ temp->source_file = 0;
+#if defined (ARRAY_VARS)
+ GET_ARRAY_FROM_VAR ("BASH_SOURCE", bash_source_v, bash_source_a);
+ if (bash_source_a && array_num_elements (bash_source_a) > 0)
+ temp->source_file = array_reference (bash_source_a, 0);
+#endif
+ bind_function_def (name->word, temp);
+
+ temp->source_file = 0;
+ return (make_command (cm_function_def, (SIMPLE_COM *)temp));
+}
+
+COMMAND *
+make_subshell_command (command)
+ COMMAND *command;
+{
+ SUBSHELL_COM *temp;
+
+ temp = (SUBSHELL_COM *)xmalloc (sizeof (SUBSHELL_COM));
+ temp->command = command;
+ temp->flags = CMD_WANT_SUBSHELL;
+ return (make_command (cm_subshell, (SIMPLE_COM *)temp));
+}
+
+/* Reverse the word list and redirection list in the simple command
+ has just been parsed. It seems simpler to do this here the one
+ time then by any other method that I can think of. */
+COMMAND *
+clean_simple_command (command)
+ COMMAND *command;
+{
+ if (command->type != cm_simple)
+ command_error ("clean_simple_command", CMDERR_BADTYPE, command->type, 0);
+ else
+ {
+ command->value.Simple->words =
+ REVERSE_LIST (command->value.Simple->words, WORD_LIST *);
+ command->value.Simple->redirects =
+ REVERSE_LIST (command->value.Simple->redirects, REDIRECT *);
+ }
+
+ return (command);
+}
+
+/* The Yacc grammar productions have a problem, in that they take a
+ list followed by an ampersand (`&') and do a simple command connection,
+ making the entire list effectively asynchronous, instead of just
+ the last command. This means that when the list is executed, all
+ the commands have stdin set to /dev/null when job control is not
+ active, instead of just the last. This is wrong, and needs fixing
+ up. This function takes the `&' and applies it to the last command
+ in the list. This is done only for lists connected by `;'; it makes
+ `;' bind `tighter' than `&'. */
+COMMAND *
+connect_async_list (command, command2, connector)
+ COMMAND *command, *command2;
+ int connector;
+{
+ COMMAND *t, *t1, *t2;
+
+ t1 = command;
+ t = command->value.Connection->second;
+
+ if (!t || (command->flags & CMD_WANT_SUBSHELL) ||
+ command->value.Connection->connector != ';')
+ {
+ t = command_connect (command, command2, connector);
+ return t;
+ }
+
+ /* This is just defensive programming. The Yacc precedence rules
+ will generally hand this function a command where t points directly
+ to the command we want (e.g. given a ; b ; c ; d &, t1 will point
+ to the `a ; b ; c' list and t will be the `d'). We only want to do
+ this if the list is not being executed as a unit in the background
+ with `( ... )', so we have to check for CMD_WANT_SUBSHELL. That's
+ the only way to tell. */
+ while (((t->flags & CMD_WANT_SUBSHELL) == 0) && t->type == cm_connection &&
+ t->value.Connection->connector == ';')
+ {
+ t1 = t;
+ t = t->value.Connection->second;
+ }
+ /* Now we have t pointing to the last command in the list, and
+ t1->value.Connection->second == t. */
+ t2 = command_connect (t, command2, connector);
+ t1->value.Connection->second = t2;
+ return command;
+}