diff options
Diffstat (limited to 'usr/src/common/util/getresponse.c')
| -rw-r--r-- | usr/src/common/util/getresponse.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/usr/src/common/util/getresponse.c b/usr/src/common/util/getresponse.c new file mode 100644 index 0000000000..cc838a7ab1 --- /dev/null +++ b/usr/src/common/util/getresponse.c @@ -0,0 +1,186 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <regex.h> +#include <locale.h> +#include <langinfo.h> +#include <limits.h> +#include <errno.h> +#include "getresponse.h" + +/* defaults - C locale values for yesstr, nostr, yesexpr (LC_MESSAGES) */ +#define DEFAULT_YESSTR "yes" +#define DEFAULT_NOSTR "no" +#define DEFAULT_YESEXPR "^[yY]" +#define DEFAULT_NOEXPR "^[nN]" + +#define FREE_MEM \ + if (yesstr) \ + free(yesstr); \ + if (nostr) \ + free(nostr); \ + if (yesexpr) \ + free(yesexpr); \ + if (noexpr) \ + free(noexpr) + +#define SET_DEFAULT_STRS \ + yesstr = DEFAULT_YESSTR; \ + nostr = DEFAULT_NOSTR; \ + yesexpr = DEFAULT_YESEXPR; \ + noexpr = DEFAULT_NOEXPR; + +/* variables used by getresponse functions */ +char *yesstr = NULL; +char *nostr = NULL; + +/* for regcomp()/regexec() yesexpr and noexpr */ +static regex_t preg_yes, preg_no; + +/* + * This function compiles a regular expression that is used to match an + * affirmative response from the user, and also assigns the strings used + * in the prompts that request affirmative or negative responses. The + * locale's values for YESEXPR, NOEXPR, YESSTR and NOSTR are used. + * + * If there are any problems using the locale's YESEXPR, NOEXPR, YESSTR or NOSTR + * values, default values of YESEXPR, YESSTR and NOSTR will be used + * as a fallback. The default values are the same as the C locale values. + */ +int +init_yes(void) +{ + int fallback = 0; + char *yesexpr; + char *noexpr; + + /* get yes expression and strings for yes/no prompts */ + yesstr = strdup(nl_langinfo(YESSTR)); + nostr = strdup(nl_langinfo(NOSTR)); + yesexpr = strdup(nl_langinfo(YESEXPR)); + noexpr = strdup(nl_langinfo(NOEXPR)); + + if (yesstr == NULL || nostr == NULL || + yesexpr == NULL || noexpr == NULL) { + FREE_MEM; + errno = ENOMEM; + return (-1); + } + + /* if problem with locale strings, use default values */ + if (*yesstr == '\0' || *nostr == '\0' || + *yesexpr == '\0' || *noexpr == '\0') { + FREE_MEM; + SET_DEFAULT_STRS; + fallback = 1; + } + /* Compile the yes and no expressions */ + while (regcomp(&preg_yes, yesexpr, REG_EXTENDED | REG_NOSUB) != 0 || + regcomp(&preg_no, noexpr, REG_EXTENDED | REG_NOSUB) != 0) { + if (fallback == 1) { + /* The fallback yesexpr failed, so exit */ + errno = EINVAL; + return (-1); + } + /* The locale's yesexpr or noexpr failed so use fallback */ + FREE_MEM; + SET_DEFAULT_STRS; + fallback = 1; + } + return (0); +} + +static int +yes_no(int (*func)(char *)) +{ + int i, b; + char ans[LINE_MAX + 1]; + + /* Get user's answer */ + for (i = 0; b = getchar(); i++) { + if (b == '\n' || b == '\0' || b == EOF) + break; + if (i < LINE_MAX) + ans[i] = b; + } + if (i >= LINE_MAX) + ans[LINE_MAX] = '\0'; + else + ans[i] = '\0'; + + return (func(ans)); +} + +static int +yes_no_check(char *ans, regex_t *reg1, regex_t *reg2) +{ + if (regexec(reg1, ans, 0, NULL, 0) == 0) { + if (regexec(reg2, ans, 0, NULL, 0) == 0) { + /* Both Expressions Match (reg2 conservative) */ + return (0); + } + /* Match */ + return (1); + } + return (0); +} + +/* + * yes_check() returns 1 if the input string is matched by yesexpr and is + * not matched by noexpr; otherwise yes_check() returns 0. + */ +int +yes_check(char *ans) +{ + return (yes_no_check(ans, &preg_yes, &preg_no)); +} + +/* + * no_check() returns 1 if the input string is matched by noexpr and is + * not matched by yesexpr; otherwise no_check() returns 0. + */ +int +no_check(char *ans) +{ + return (yes_no_check(ans, &preg_no, &preg_yes)); +} + +int +yes(void) +{ + return (yes_no(yes_check)); +} + +int +no(void) +{ + return (yes_no(no_check)); +} |