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Diffstat (limited to '')
-rw-r--r-- | builtins/break.def | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/builtins/break.def b/builtins/break.def new file mode 100644 index 0000000..b73ed5e --- /dev/null +++ b/builtins/break.def @@ -0,0 +1,143 @@ +This file is break.def, from which is created break.c. +It implements the builtins "break" and "continue" in Bash. + +Copyright (C) 1987-2020 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/>. + +$PRODUCES break.c + +$BUILTIN break +$FUNCTION break_builtin +$SHORT_DOC break [n] +Exit for, while, or until loops. + +Exit a FOR, WHILE or UNTIL loop. If N is specified, break N enclosing +loops. + +Exit Status: +The exit status is 0 unless N is not greater than or equal to 1. +$END +#include <config.h> + +#if defined (HAVE_UNISTD_H) +# ifdef _MINIX +# include <sys/types.h> +# endif +# include <unistd.h> +#endif + +#include "../bashintl.h" + +#include "../shell.h" +#include "../execute_cmd.h" +#include "common.h" + +static int check_loop_level PARAMS((void)); + +/* The depth of while's and until's. */ +int loop_level = 0; + +/* Non-zero when a "break" instruction is encountered. */ +int breaking = 0; + +/* Non-zero when we have encountered a continue instruction. */ +int continuing = 0; + +/* Set up to break x levels, where x defaults to 1, but can be specified + as the first argument. */ +int +break_builtin (list) + WORD_LIST *list; +{ + intmax_t newbreak; + + CHECK_HELPOPT (list); + + if (check_loop_level () == 0) + return (EXECUTION_SUCCESS); + + (void)get_numeric_arg (list, 1, &newbreak); + + if (newbreak <= 0) + { + sh_erange (list->word->word, _("loop count")); + breaking = loop_level; + return (EXECUTION_FAILURE); + } + + if (newbreak > loop_level) + newbreak = loop_level; + + breaking = newbreak; + + return (EXECUTION_SUCCESS); +} + +$BUILTIN continue +$FUNCTION continue_builtin +$SHORT_DOC continue [n] +Resume for, while, or until loops. + +Resumes the next iteration of the enclosing FOR, WHILE or UNTIL loop. +If N is specified, resumes the Nth enclosing loop. + +Exit Status: +The exit status is 0 unless N is not greater than or equal to 1. +$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; + + CHECK_HELPOPT (list); + + if (check_loop_level () == 0) + return (EXECUTION_SUCCESS); + + (void)get_numeric_arg (list, 1, &newcont); + + 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); +} |