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Diffstat (limited to 'builtins/break.def')
-rw-r--r-- | builtins/break.def | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/builtins/break.def b/builtins/break.def new file mode 100644 index 0000000..e61d502 --- /dev/null +++ b/builtins/break.def @@ -0,0 +1,132 @@ +This file is break.def, from which is created break.c. +It implements the builtins "break" and "continue" in Bash. + +Copyright (C) 1987-2003 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. + +$PRODUCES break.c + +$BUILTIN break +$FUNCTION break_builtin +$SHORT_DOC break [n] +Exit from within a FOR, WHILE or UNTIL loop. If N is specified, +break N levels. +$END +#include <config.h> + +#if defined (HAVE_UNISTD_H) +# ifdef _MINIX +# include <sys/types.h> +# endif +# include <unistd.h> +#endif + +#include "../bashintl.h" + +#include "../shell.h" +#include "common.h" + +extern char *this_command_name; +extern int posixly_correct; + +static int check_loop_level __P((void)); + +/* The depth of while's and until's. */ +int loop_level = 0; + +/* Non-zero when a "break" instruction is encountered. */ +int breaking = 0; + +/* Non-zero when we have encountered a continue instruction. */ +int continuing = 0; + +/* Set up to break x levels, where x defaults to 1, but can be specified + as the first argument. */ +int +break_builtin (list) + WORD_LIST *list; +{ + intmax_t newbreak; + + if (check_loop_level () == 0) + return (EXECUTION_SUCCESS); + + newbreak = get_numeric_arg (list, 1); + + if (newbreak <= 0) + { + sh_erange (list->word->word, "loop count"); + breaking = loop_level; + return (EXECUTION_FAILURE); + } + + if (newbreak > loop_level) + newbreak = loop_level; + + breaking = newbreak; + + return (EXECUTION_SUCCESS); +} + +$BUILTIN continue +$FUNCTION continue_builtin +$SHORT_DOC continue [n] +Resume the next iteration of the enclosing FOR, WHILE or UNTIL loop. +If N is specified, resume at the N-th enclosing loop. +$END + +/* Set up to continue x levels, where x defaults to 1, but can be specified + as the first argument. */ +int +continue_builtin (list) + WORD_LIST *list; +{ + intmax_t newcont; + + if (check_loop_level () == 0) + return (EXECUTION_SUCCESS); + + newcont = get_numeric_arg (list, 1); + + if (newcont <= 0) + { + sh_erange (list->word->word, "loop count"); + breaking = loop_level; + return (EXECUTION_FAILURE); + } + + if (newcont > loop_level) + newcont = loop_level; + + continuing = newcont; + + return (EXECUTION_SUCCESS); +} + +/* Return non-zero if a break or continue command would be okay. + Print an error message if break or continue is meaningless here. */ +static int +check_loop_level () +{ +#if defined (BREAK_COMPLAINS) + if (loop_level == 0 && posixly_correct == 0) + builtin_error (_("only meaningful in a `for', `while', or `until' loop")); +#endif /* BREAK_COMPLAINS */ + + return (loop_level); +} |