diff options
Diffstat (limited to 'login-utils/chsh.c')
| -rw-r--r-- | login-utils/chsh.c | 117 |
1 files changed, 90 insertions, 27 deletions
diff --git a/login-utils/chsh.c b/login-utils/chsh.c index 1fb377593..c6eab1554 100644 --- a/login-utils/chsh.c +++ b/login-utils/chsh.c @@ -67,6 +67,8 @@ struct sinfo { char *shell; }; +/* global due readline completion */ +static char **global_shells = NULL; static void __attribute__((__noreturn__)) usage (FILE *fp) { @@ -87,24 +89,31 @@ static void __attribute__((__noreturn__)) usage (FILE *fp) } /* - * get_shell_list () -- if the given shell appears in /etc/shells, - * return true. if not, return false. - * if the given shell is NULL, /etc/shells is outputted to stdout. + * free_shells () -- free shells allocations. */ -static int get_shell_list(const char *shell_name) +static void free_shells(void) +{ + char **s; + + for (s = global_shells; *s; s++) + free(*s); + free(global_shells); +} + +/* + * init_shells () -- fill shells variable from /etc/shells, + */ +static int init_shells(char ***shells) { FILE *fp; - int found = 0; char *buf = NULL; - size_t sz = 0; + size_t sz = 0, shellsz = 8, n = 0; ssize_t len; + *shells = xmalloc(sizeof(char *) * shellsz); fp = fopen(_PATH_SHELLS, "r"); - if (!fp) { - if (!shell_name) - warnx(_("No known shells.")); - return 0; - } + if (!fp) + return 1; while ((len = getline(&buf, &sz, fp)) != -1) { /* ignore comments and blank lines */ if (*buf == '#' || len < 2) @@ -112,26 +121,77 @@ static int get_shell_list(const char *shell_name) /* strip the ending newline */ if (buf[len - 1] == '\n') buf[len - 1] = 0; - /* check or output the shell */ + (*shells)[n++] = buf; + if (shellsz < n) { + shellsz *= 2; + shells = xrealloc(shells, sizeof(char *) * shellsz); + } + buf = NULL; + } + free(buf); + (*shells)[n] = NULL; + fclose(fp); + atexit(free_shells); + return 0; +} + +/* + * get_shell_list () -- if the given shell appears in /etc/shells, + * return true. if not, return false. + * if the given shell is NULL, /etc/shells is outputted to stdout. + */ +static int get_shell_list(const char *shell_name, char ***shells) +{ + char **s; + int found = 0; + + if (!shells) + return found; + s = *shells; + for (s = *shells; *s; s++) { if (shell_name) { - if (!strcmp(shell_name, buf)) { + if (!strcmp(shell_name, *s)) { found = 1; break; } } else - printf("%s\n", buf); + printf("%s\n", *s); } - fclose(fp); - free(buf); return found; } +#ifdef HAVE_LIBREADLINE +static char *shell_name_generator(const char *text, int state) +{ + static size_t len, idx; + char *s; + + if (!state) { + idx = 0; + len = strlen(text); + } + while ((s = global_shells[idx++])) { + if (strncmp(s, text, len) == 0) + return xstrdup(s); + } + return NULL; +} + +static char **shell_name_completion(const char *text, + int start __attribute__((__unused__)), + int end __attribute__((__unused__))) +{ + rl_attempted_completion_over = 1; + return rl_completion_matches(text, shell_name_generator); +} +#endif + /* * parse_argv () -- * parse the command line arguments, and fill in "pinfo" with any * information from the command line. */ -static void parse_argv(int argc, char **argv, struct sinfo *pinfo) +static void parse_argv(int argc, char **argv, struct sinfo *pinfo, char ***shells) { static const struct option long_options[] = { {"shell", required_argument, NULL, 's'}, @@ -151,7 +211,8 @@ static void parse_argv(int argc, char **argv, struct sinfo *pinfo) case 'h': usage(stdout); case 'l': - get_shell_list(NULL); + init_shells(shells); + get_shell_list(NULL, shells); exit(EXIT_SUCCESS); case 's': if (!optarg) @@ -178,15 +239,16 @@ static char *ask_new_shell(char *question, char *oldshell) { int len; char *ans = NULL; -#ifndef HAVE_LIBREADLINE +#ifdef HAVE_LIBREADLINE + rl_attempted_completion_function = shell_name_completion; +#else size_t dummy = 0; #endif - if (!oldshell) oldshell = ""; - printf("%s [%s]: ", question, oldshell); + printf("%s [%s]\n", question, oldshell); #ifdef HAVE_LIBREADLINE - if ((ans = readline(NULL)) == NULL) + if ((ans = readline("> ")) == NULL) #else if (getline(&ans, &dummy, stdin) < 0) #endif @@ -203,7 +265,7 @@ static char *ask_new_shell(char *question, char *oldshell) * check_shell () -- if the shell is completely invalid, print * an error and exit. */ -static void check_shell(const char *shell) +static void check_shell(const char *shell, char ***shells) { if (*shell != '/') errx(EXIT_FAILURE, _("shell must be a full path name")); @@ -213,7 +275,7 @@ static void check_shell(const char *shell) errx(EXIT_FAILURE, _("\"%s\" is not executable"), shell); if (illegal_passwd_chars(shell)) errx(EXIT_FAILURE, _("%s: has illegal characters"), shell); - if (!get_shell_list(shell)) { + if (!get_shell_list(shell, shells)) { #ifdef ONLY_LISTED_SHELLS if (!getuid()) warnx(_("Warning: \"%s\" is not listed in %s."), shell, @@ -245,7 +307,7 @@ int main(int argc, char **argv) textdomain(PACKAGE); atexit(close_stdout); - parse_argv(argc, argv, &info); + parse_argv(argc, argv, &info, &global_shells); if (!info.username) { pw = getpwuid(uid); if (!pw) @@ -304,7 +366,8 @@ int main(int argc, char **argv) _("running UID doesn't match UID of user we're " "altering, shell change denied")); } - if (uid != 0 && !get_shell_list(oldshell)) { + init_shells(&global_shells); + if (uid != 0 && !get_shell_list(oldshell, &global_shells)) { errno = EACCES; err(EXIT_FAILURE, _("your shell is not in %s, " "shell change denied"), _PATH_SHELLS); @@ -323,7 +386,7 @@ int main(int argc, char **argv) return EXIT_SUCCESS; } - check_shell(info.shell); + check_shell(info.shell, &global_shells); if (!nullshell && strcmp(oldshell, info.shell) == 0) errx(EXIT_SUCCESS, _("Shell not changed.")); |