diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:38:56 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:38:56 +0000 |
commit | 6c20c8ed2cb9ab69a1a57ccb2b9b79969a808321 (patch) | |
tree | f63ce19d57fad3ac4a15bc26dbfbfa2b834111b5 /make_cmd.c | |
parent | Initial commit. (diff) | |
download | bash-6c20c8ed2cb9ab69a1a57ccb2b9b79969a808321.tar.xz bash-6c20c8ed2cb9ab69a1a57ccb2b9b79969a808321.zip |
Adding upstream version 5.2.15.upstream/5.2.15upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'make_cmd.c')
-rw-r--r-- | make_cmd.c | 907 |
1 files changed, 907 insertions, 0 deletions
diff --git a/make_cmd.c b/make_cmd.c new file mode 100644 index 0000000..98151a4 --- /dev/null +++ b/make_cmd.c @@ -0,0 +1,907 @@ +/* make_cmd.c -- Functions for making instances of the various + parser constructs. */ + +/* Copyright (C) 1989-2022 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>. +*/ + +#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 "shell.h" +#include "execute_cmd.h" +#include "parser.h" +#include "flags.h" +#include "input.h" + +#if defined (JOB_CONTROL) +#include "jobs.h" +#endif + +#include "shmbutil.h" + +int here_doc_first_line = 0; + +/* Object caching */ +sh_obj_cache_t wdcache = {0, 0, 0}; +sh_obj_cache_t wlcache = {0, 0, 0}; + +#define WDCACHESIZE 128 +#define WLCACHESIZE 128 + +static COMMAND *make_for_or_select PARAMS((enum command_type, WORD_DESC *, WORD_LIST *, COMMAND *, int)); +#if defined (ARITH_FOR_COMMAND) +static WORD_LIST *make_arith_for_expr PARAMS((char *)); +#endif +static COMMAND *make_until_or_while PARAMS((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 + set_exit_status (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_NOTILDE|W_NOPROCSUB; /* 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, i; + + 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 */ + i = skip_to_delim (start, 0, ";", SD_NOJMP|SD_NOPROCSUB); + s = start + i; + + t = (i > 0) ? substring (start, 0, i) : (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); + free (init); + free (test); + free (step); + set_exit_status (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); + set_exit_status (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 + set_exit_status (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 + set_exit_status (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 == 0) + { + command = make_bare_simple_command (); + parser_state |= PST_REDIRLIST; + } + + if (element.word) + { + command->value.Simple->words = make_word_list (element.word, command->value.Simple->words); + parser_state &= ~PST_REDIRLIST; + } + 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, lineno) + REDIRECT *temp; + int lineno; +{ + 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; + + full_line = document = (char *)NULL; + document_index = document_size = 0; + + delim_unquoted = (temp->redirectee.filename->flags & W_QUOTED) == 0; + + /* Quote removal is the only expansion performed on the delimiter + for here documents, making it an extremely special case. */ + /* "If any part of word is quoted, the delimiter shall be formed by + performing quote removal on word." */ + if (delim_unquoted == 0) + redir_word = string_quote_removal (temp->redirectee.filename->word, 0); + else + redir_word = savestring (temp->redirectee.filename->word); + + /* 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. */ + while (full_line = read_secondary_line (delim_unquoted)) + { + register char *line; + int len; + + here_doc_first_line = 0; + line = full_line; + line_number++; + + /* If set -v is in effect, echo the line read. read_secondary_line/ + read_a_line leaves the newline at the end, so don't print another. */ + if (echo_input_at_read) + fprintf (stderr, "%s", line); + + 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') + break; + + while (*line == '\t') + line++; + } + + if (*line == 0) + continue; + + if (STREQN (line, redir_word, redir_len) && line[redir_len] == '\n') + break; + + /* Backwards compatibility here */ + if (STREQN (line, redir_word, redir_len) && (parser_state & PST_EOFTOKEN) && shell_eof_token && strchr (line+redir_len, shell_eof_token)) + { + shell_ungets (line + redir_len); + full_line = 0; + break; + } + + 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; + } + + if (full_line == 0) + internal_warning (_("here-document at line %d delimited by end-of-file (wanted `%s')"), lineno, redir_word); + +document_done: + if (document) + document[document_index] = '\0'; + else + { + document = (char *)xmalloc (1); + document[0] = '\0'; + } + temp->redirectee.filename->word = document; + here_doc_first_line = 0; +} + +/* 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, flags) + REDIRECTEE source; + enum r_instruction instruction; + REDIRECTEE dest_and_filename; + int flags; +{ + 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->here_doc_eof = 0; + temp->instruction = instruction; + temp->flags = 0; + temp->rflags = flags; + temp->next = (REDIRECT *)NULL; + + switch (instruction) + { + + case r_output_direction: /* >foo */ + case r_output_force: /* >| foo */ + case r_err_and_out: /* &>filename */ + temp->flags = O_TRUNC | O_WRONLY | O_CREAT; + break; + + case r_appending_to: /* >>foo */ + case r_append_err_and_out: /* &>> filename */ + 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; +#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 + /* Assume that shell functions without a source file before the shell is + initialized come from the environment. Otherwise default to "main" + (usually functions being defined interactively) */ + if (temp->source_file == 0) + temp->source_file = shell_initialized ? "main" : "environment"; + +#if defined (DEBUGGER) + bind_function_def (name->word, temp, 0); +#endif + + temp->source_file = temp->source_file ? savestring (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; + temp->line = line_number; + return (make_command (cm_subshell, (SIMPLE_COM *)temp)); +} + +COMMAND * +make_coproc_command (name, command) + char *name; + COMMAND *command; +{ + COPROC_COM *temp; + + temp = (COPROC_COM *)xmalloc (sizeof (COPROC_COM)); + temp->name = savestring (name); + temp->command = command; + temp->flags = CMD_WANT_SUBSHELL|CMD_COPROC_SUBSHELL; + return (make_command (cm_coproc, (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 *); + } + + parser_state &= ~PST_REDIRLIST; + 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; +} |