summaryrefslogtreecommitdiffstats
path: root/builtins/common.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--builtins/common.c910
1 files changed, 910 insertions, 0 deletions
diff --git a/builtins/common.c b/builtins/common.c
new file mode 100644
index 0000000..00be24e
--- /dev/null
+++ b/builtins/common.c
@@ -0,0 +1,910 @@
+/* common.c - utility functions for all builtins */
+
+/* Copyright (C) 1987-2017 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>
+
+#if defined (HAVE_UNISTD_H)
+# ifdef _MINIX
+# include <sys/types.h>
+# endif
+# include <unistd.h>
+#endif
+
+#include <stdio.h>
+#include <chartypes.h>
+#include "../bashtypes.h"
+#include "posixstat.h"
+#include <signal.h>
+
+#include <errno.h>
+
+#if defined (PREFER_STDARG)
+# include <stdarg.h>
+#else
+# include <varargs.h>
+#endif
+
+#include "../bashansi.h"
+#include "../bashintl.h"
+
+#define NEED_FPURGE_DECL
+
+#include "../shell.h"
+#include "maxpath.h"
+#include "../flags.h"
+#include "../parser.h"
+#include "../jobs.h"
+#include "../builtins.h"
+#include "../input.h"
+#include "../execute_cmd.h"
+#include "../trap.h"
+#include "bashgetopt.h"
+#include "common.h"
+#include "builtext.h"
+#include <tilde/tilde.h>
+
+#if defined (HISTORY)
+# include "../bashhist.h"
+#endif
+
+#if !defined (errno)
+extern int errno;
+#endif /* !errno */
+
+extern const char * const bash_getcwd_errstr;
+
+/* Used by some builtins and the mainline code. */
+sh_builtin_func_t *last_shell_builtin = (sh_builtin_func_t *)NULL;
+sh_builtin_func_t *this_shell_builtin = (sh_builtin_func_t *)NULL;
+
+/* **************************************************************** */
+/* */
+/* Error reporting, usage, and option processing */
+/* */
+/* **************************************************************** */
+
+/* This is a lot like report_error (), but it is for shell builtins
+ instead of shell control structures, and it won't ever exit the
+ shell. */
+
+static void
+builtin_error_prolog ()
+{
+ char *name;
+
+ name = get_name_for_error ();
+ fprintf (stderr, "%s: ", name);
+
+ if (interactive_shell == 0)
+ fprintf (stderr, _("line %d: "), executing_line_number ());
+
+ if (this_command_name && *this_command_name)
+ fprintf (stderr, "%s: ", this_command_name);
+}
+
+void
+#if defined (PREFER_STDARG)
+builtin_error (const char *format, ...)
+#else
+builtin_error (format, va_alist)
+ const char *format;
+ va_dcl
+#endif
+{
+ va_list args;
+
+ builtin_error_prolog ();
+
+ SH_VA_START (args, format);
+
+ vfprintf (stderr, format, args);
+ va_end (args);
+ fprintf (stderr, "\n");
+}
+
+void
+#if defined (PREFER_STDARG)
+builtin_warning (const char *format, ...)
+#else
+builtin_warning (format, va_alist)
+ const char *format;
+ va_dcl
+#endif
+{
+ va_list args;
+
+ builtin_error_prolog ();
+ fprintf (stderr, _("warning: "));
+
+ SH_VA_START (args, format);
+
+ vfprintf (stderr, format, args);
+ va_end (args);
+ fprintf (stderr, "\n");
+}
+
+/* Print a usage summary for the currently-executing builtin command. */
+void
+builtin_usage ()
+{
+ if (this_command_name && *this_command_name)
+ fprintf (stderr, _("%s: usage: "), this_command_name);
+ fprintf (stderr, "%s\n", _(current_builtin->short_doc));
+ fflush (stderr);
+}
+
+/* Return if LIST is NULL else barf and jump to top_level. Used by some
+ builtins that do not accept arguments. */
+void
+no_args (list)
+ WORD_LIST *list;
+{
+ if (list)
+ {
+ builtin_error (_("too many arguments"));
+ top_level_cleanup ();
+ jump_to_top_level (DISCARD);
+ }
+}
+
+/* Check that no options were given to the currently-executing builtin,
+ and return 0 if there were options. */
+int
+no_options (list)
+ WORD_LIST *list;
+{
+ int opt;
+
+ reset_internal_getopt ();
+ if ((opt = internal_getopt (list, "")) != -1)
+ {
+ if (opt == GETOPT_HELP)
+ {
+ builtin_help ();
+ return (2);
+ }
+ builtin_usage ();
+ return (1);
+ }
+ return (0);
+}
+
+void
+sh_needarg (s)
+ char *s;
+{
+ builtin_error (_("%s: option requires an argument"), s);
+}
+
+void
+sh_neednumarg (s)
+ char *s;
+{
+ builtin_error (_("%s: numeric argument required"), s);
+}
+
+void
+sh_notfound (s)
+ char *s;
+{
+ builtin_error (_("%s: not found"), s);
+}
+
+/* Function called when one of the builtin commands detects an invalid
+ option. */
+void
+sh_invalidopt (s)
+ char *s;
+{
+ builtin_error (_("%s: invalid option"), s);
+}
+
+void
+sh_invalidoptname (s)
+ char *s;
+{
+ builtin_error (_("%s: invalid option name"), s);
+}
+
+void
+sh_invalidid (s)
+ char *s;
+{
+ builtin_error (_("`%s': not a valid identifier"), s);
+}
+
+void
+sh_invalidnum (s)
+ char *s;
+{
+ char *msg;
+
+ if (*s == '0' && isdigit ((unsigned char)s[1]))
+ msg = _("invalid octal number");
+ else if (*s == '0' && s[1] == 'x')
+ msg = _("invalid hex number");
+ else
+ msg = _("invalid number");
+ builtin_error ("%s: %s", s, msg);
+}
+
+void
+sh_invalidsig (s)
+ char *s;
+{
+ builtin_error (_("%s: invalid signal specification"), s);
+}
+
+void
+sh_badpid (s)
+ char *s;
+{
+ builtin_error (_("`%s': not a pid or valid job spec"), s);
+}
+
+void
+sh_readonly (s)
+ const char *s;
+{
+ builtin_error (_("%s: readonly variable"), s);
+}
+
+void
+sh_erange (s, desc)
+ char *s, *desc;
+{
+ if (s)
+ builtin_error (_("%s: %s out of range"), s, desc ? desc : _("argument"));
+ else
+ builtin_error (_("%s out of range"), desc ? desc : _("argument"));
+}
+
+#if defined (JOB_CONTROL)
+void
+sh_badjob (s)
+ char *s;
+{
+ builtin_error (_("%s: no such job"), s);
+}
+
+void
+sh_nojobs (s)
+ char *s;
+{
+ if (s)
+ builtin_error (_("%s: no job control"), s);
+ else
+ builtin_error (_("no job control"));
+}
+#endif
+
+#if defined (RESTRICTED_SHELL)
+void
+sh_restricted (s)
+ char *s;
+{
+ if (s)
+ builtin_error (_("%s: restricted"), s);
+ else
+ builtin_error (_("restricted"));
+}
+#endif
+
+void
+sh_notbuiltin (s)
+ char *s;
+{
+ builtin_error (_("%s: not a shell builtin"), s);
+}
+
+void
+sh_wrerror ()
+{
+#if defined (DONT_REPORT_BROKEN_PIPE_WRITE_ERRORS) && defined (EPIPE)
+ if (errno != EPIPE)
+#endif /* DONT_REPORT_BROKEN_PIPE_WRITE_ERRORS && EPIPE */
+ builtin_error (_("write error: %s"), strerror (errno));
+}
+
+void
+sh_ttyerror (set)
+ int set;
+{
+ if (set)
+ builtin_error (_("error setting terminal attributes: %s"), strerror (errno));
+ else
+ builtin_error (_("error getting terminal attributes: %s"), strerror (errno));
+}
+
+int
+sh_chkwrite (s)
+ int s;
+{
+ QUIT;
+ fflush (stdout);
+ QUIT;
+ if (ferror (stdout))
+ {
+ sh_wrerror ();
+ fpurge (stdout);
+ clearerr (stdout);
+ return (EXECUTION_FAILURE);
+ }
+ return (s);
+}
+
+/* **************************************************************** */
+/* */
+/* Shell positional parameter manipulation */
+/* */
+/* **************************************************************** */
+
+/* Convert a WORD_LIST into a C-style argv. Return the number of elements
+ in the list in *IP, if IP is non-null. A convenience function for
+ loadable builtins; also used by `test'. */
+char **
+make_builtin_argv (list, ip)
+ WORD_LIST *list;
+ int *ip;
+{
+ char **argv;
+
+ argv = strvec_from_word_list (list, 0, 1, ip);
+ argv[0] = this_command_name;
+ return argv;
+}
+
+/* Remember LIST in $1 ... $9, and REST_OF_ARGS. If DESTRUCTIVE is
+ non-zero, then discard whatever the existing arguments are, else
+ only discard the ones that are to be replaced. */
+void
+remember_args (list, destructive)
+ WORD_LIST *list;
+ int destructive;
+{
+ register int i;
+
+ for (i = 1; i < 10; i++)
+ {
+ if ((destructive || list) && dollar_vars[i])
+ {
+ free (dollar_vars[i]);
+ dollar_vars[i] = (char *)NULL;
+ }
+
+ if (list)
+ {
+ dollar_vars[i] = savestring (list->word->word);
+ list = list->next;
+ }
+ }
+
+ /* If arguments remain, assign them to REST_OF_ARGS.
+ Note that copy_word_list (NULL) returns NULL, and
+ that dispose_words (NULL) does nothing. */
+ if (destructive || list)
+ {
+ dispose_words (rest_of_args);
+ rest_of_args = copy_word_list (list);
+ }
+
+ if (destructive)
+ set_dollar_vars_changed ();
+
+ invalidate_cached_quoted_dollar_at ();
+}
+
+static int changed_dollar_vars;
+
+/* Have the dollar variables been reset to new values since we last
+ checked? */
+int
+dollar_vars_changed ()
+{
+ return (changed_dollar_vars);
+}
+
+void
+set_dollar_vars_unchanged ()
+{
+ changed_dollar_vars = 0;
+}
+
+void
+set_dollar_vars_changed ()
+{
+ if (variable_context)
+ changed_dollar_vars |= ARGS_FUNC;
+ else if (this_shell_builtin == set_builtin)
+ changed_dollar_vars |= ARGS_SETBLTIN;
+ else
+ changed_dollar_vars |= ARGS_INVOC;
+}
+
+/* **************************************************************** */
+/* */
+/* Validating numeric input and arguments */
+/* */
+/* **************************************************************** */
+
+/* Read a numeric arg for this_command_name, the name of the shell builtin
+ that wants it. LIST is the word list that the arg is to come from.
+ Accept only the numeric argument; report an error if other arguments
+ follow. If FATAL is 1, call throw_to_top_level, which exits the
+ shell; if it's 2, call jump_to_top_level (DISCARD), which aborts the
+ current command; if FATAL is 0, return an indication of an invalid
+ number by setting *NUMOK == 0 and return -1. */
+int
+get_numeric_arg (list, fatal, count)
+ WORD_LIST *list;
+ int fatal;
+ intmax_t *count;
+{
+ char *arg;
+
+ if (count)
+ *count = 1;
+
+ if (list && list->word && ISOPTION (list->word->word, '-'))
+ list = list->next;
+
+ if (list)
+ {
+ arg = list->word->word;
+ if (arg == 0 || (legal_number (arg, count) == 0))
+ {
+ sh_neednumarg (list->word->word ? list->word->word : "`'");
+ if (fatal == 0)
+ return 0;
+ else if (fatal == 1) /* fatal == 1; abort */
+ throw_to_top_level ();
+ else /* fatal == 2; discard current command */
+ {
+ top_level_cleanup ();
+ jump_to_top_level (DISCARD);
+ }
+ }
+ no_args (list->next);
+ }
+
+ return (1);
+}
+
+/* Get an eight-bit status value from LIST */
+int
+get_exitstat (list)
+ WORD_LIST *list;
+{
+ int status;
+ intmax_t sval;
+ char *arg;
+
+ if (list && list->word && ISOPTION (list->word->word, '-'))
+ list = list->next;
+
+ if (list == 0)
+ {
+ /* If we're not running the DEBUG trap, the return builtin, when not
+ given any arguments, uses the value of $? before the trap ran. If
+ given an argument, return uses it. This means that the trap can't
+ change $?. The DEBUG trap gets to change $?, though, since that is
+ part of its reason for existing, and because the extended debug mode
+ does things with the return value. */
+ if (this_shell_builtin == return_builtin && running_trap > 0 && running_trap != DEBUG_TRAP+1)
+ return (trap_saved_exit_value);
+ return (last_command_exit_value);
+ }
+
+ arg = list->word->word;
+ if (arg == 0 || legal_number (arg, &sval) == 0)
+ {
+ sh_neednumarg (list->word->word ? list->word->word : "`'");
+ return EX_BADUSAGE;
+ }
+ no_args (list->next);
+
+ status = sval & 255;
+ return status;
+}
+
+/* Return the octal number parsed from STRING, or -1 to indicate
+ that the string contained a bad number. */
+int
+read_octal (string)
+ char *string;
+{
+ int result, digits;
+
+ result = digits = 0;
+ while (*string && ISOCTAL (*string))
+ {
+ digits++;
+ result = (result * 8) + (*string++ - '0');
+ if (result > 07777)
+ return -1;
+ }
+
+ if (digits == 0 || *string)
+ result = -1;
+
+ return (result);
+}
+
+/* **************************************************************** */
+/* */
+/* Manipulating the current working directory */
+/* */
+/* **************************************************************** */
+
+/* Return a consed string which is the current working directory.
+ FOR_WHOM is the name of the caller for error printing. */
+char *the_current_working_directory = (char *)NULL;
+
+char *
+get_working_directory (for_whom)
+ char *for_whom;
+{
+ if (no_symbolic_links)
+ {
+ FREE (the_current_working_directory);
+ the_current_working_directory = (char *)NULL;
+ }
+
+ if (the_current_working_directory == 0)
+ {
+#if defined (GETCWD_BROKEN)
+ the_current_working_directory = getcwd (0, PATH_MAX);
+#else
+ the_current_working_directory = getcwd (0, 0);
+#endif
+ if (the_current_working_directory == 0)
+ {
+ fprintf (stderr, _("%s: error retrieving current directory: %s: %s\n"),
+ (for_whom && *for_whom) ? for_whom : get_name_for_error (),
+ _(bash_getcwd_errstr), strerror (errno));
+ return (char *)NULL;
+ }
+ }
+
+ return (savestring (the_current_working_directory));
+}
+
+/* Make NAME our internal idea of the current working directory. */
+void
+set_working_directory (name)
+ char *name;
+{
+ FREE (the_current_working_directory);
+ the_current_working_directory = savestring (name);
+}
+
+/* **************************************************************** */
+/* */
+/* Job control support functions */
+/* */
+/* **************************************************************** */
+
+#if defined (JOB_CONTROL)
+int
+get_job_by_name (name, flags)
+ const char *name;
+ int flags;
+{
+ register int i, wl, cl, match, job;
+ register PROCESS *p;
+ register JOB *j;
+
+ job = NO_JOB;
+ wl = strlen (name);
+ for (i = js.j_jobslots - 1; i >= 0; i--)
+ {
+ j = get_job_by_jid (i);
+ if (j == 0 || ((flags & JM_STOPPED) && J_JOBSTATE(j) != JSTOPPED))
+ continue;
+
+ p = j->pipe;
+ do
+ {
+ if (flags & JM_EXACT)
+ {
+ cl = strlen (p->command);
+ match = STREQN (p->command, name, cl);
+ }
+ else if (flags & JM_SUBSTRING)
+ match = strcasestr (p->command, name) != (char *)0;
+ else
+ match = STREQN (p->command, name, wl);
+
+ if (match == 0)
+ {
+ p = p->next;
+ continue;
+ }
+ else if (flags & JM_FIRSTMATCH)
+ return i; /* return first match */
+ else if (job != NO_JOB)
+ {
+ if (this_shell_builtin)
+ builtin_error (_("%s: ambiguous job spec"), name);
+ else
+ internal_error (_("%s: ambiguous job spec"), name);
+ return (DUP_JOB);
+ }
+ else
+ job = i;
+ }
+ while (p != j->pipe);
+ }
+
+ return (job);
+}
+
+/* Return the job spec found in LIST. */
+int
+get_job_spec (list)
+ WORD_LIST *list;
+{
+ register char *word;
+ int job, jflags;
+
+ if (list == 0)
+ return (js.j_current);
+
+ word = list->word->word;
+
+ if (*word == '\0')
+ return (NO_JOB);
+
+ if (*word == '%')
+ word++;
+
+ if (DIGIT (*word) && all_digits (word))
+ {
+ job = atoi (word);
+ return ((job < 0 || job > js.j_jobslots) ? NO_JOB : job - 1);
+ }
+
+ jflags = 0;
+ switch (*word)
+ {
+ case 0:
+ case '%':
+ case '+':
+ return (js.j_current);
+
+ case '-':
+ return (js.j_previous);
+
+ case '?': /* Substring search requested. */
+ jflags |= JM_SUBSTRING;
+ word++;
+ /* FALLTHROUGH */
+
+ default:
+ return get_job_by_name (word, jflags);
+ }
+}
+#endif /* JOB_CONTROL */
+
+/*
+ * NOTE: `kill' calls this function with forcecols == 0
+ */
+int
+display_signal_list (list, forcecols)
+ WORD_LIST *list;
+ int forcecols;
+{
+ register int i, column;
+ char *name;
+ int result, signum, dflags;
+ intmax_t lsignum;
+
+ result = EXECUTION_SUCCESS;
+ if (!list)
+ {
+ for (i = 1, column = 0; i < NSIG; i++)
+ {
+ name = signal_name (i);
+ if (STREQN (name, "SIGJUNK", 7) || STREQN (name, "Unknown", 7))
+ continue;
+
+ if (posixly_correct && !forcecols)
+ {
+ /* This is for the kill builtin. POSIX.2 says the signal names
+ are displayed without the `SIG' prefix. */
+ if (STREQN (name, "SIG", 3))
+ name += 3;
+ printf ("%s%s", name, (i == NSIG - 1) ? "" : " ");
+ }
+ else
+ {
+ printf ("%2d) %s", i, name);
+
+ if (++column < 5)
+ printf ("\t");
+ else
+ {
+ printf ("\n");
+ column = 0;
+ }
+ }
+ }
+
+ if ((posixly_correct && !forcecols) || column != 0)
+ printf ("\n");
+ return result;
+ }
+
+ /* List individual signal names or numbers. */
+ while (list)
+ {
+ if (legal_number (list->word->word, &lsignum))
+ {
+ /* This is specified by Posix.2 so that exit statuses can be
+ mapped into signal numbers. */
+ if (lsignum > 128)
+ lsignum -= 128;
+ if (lsignum < 0 || lsignum >= NSIG)
+ {
+ sh_invalidsig (list->word->word);
+ result = EXECUTION_FAILURE;
+ list = list->next;
+ continue;
+ }
+
+ signum = lsignum;
+ name = signal_name (signum);
+ if (STREQN (name, "SIGJUNK", 7) || STREQN (name, "Unknown", 7))
+ {
+ list = list->next;
+ continue;
+ }
+ /* POSIX.2 says that `kill -l signum' prints the signal name without
+ the `SIG' prefix. */
+ printf ("%s\n", (this_shell_builtin == kill_builtin && signum > 0) ? name + 3 : name);
+ }
+ else
+ {
+ dflags = DSIG_NOCASE;
+ if (posixly_correct == 0 || this_shell_builtin != kill_builtin)
+ dflags |= DSIG_SIGPREFIX;
+ signum = decode_signal (list->word->word, dflags);
+ if (signum == NO_SIG)
+ {
+ sh_invalidsig (list->word->word);
+ result = EXECUTION_FAILURE;
+ list = list->next;
+ continue;
+ }
+ printf ("%d\n", signum);
+ }
+ list = list->next;
+ }
+ return (result);
+}
+
+/* **************************************************************** */
+/* */
+/* Finding builtin commands and their functions */
+/* */
+/* **************************************************************** */
+
+/* Perform a binary search and return the address of the builtin function
+ whose name is NAME. If the function couldn't be found, or the builtin
+ is disabled or has no function associated with it, return NULL.
+ Return the address of the builtin.
+ DISABLED_OKAY means find it even if the builtin is disabled. */
+struct builtin *
+builtin_address_internal (name, disabled_okay)
+ char *name;
+ int disabled_okay;
+{
+ int hi, lo, mid, j;
+
+ hi = num_shell_builtins - 1;
+ lo = 0;
+
+ while (lo <= hi)
+ {
+ mid = (lo + hi) / 2;
+
+ j = shell_builtins[mid].name[0] - name[0];
+
+ if (j == 0)
+ j = strcmp (shell_builtins[mid].name, name);
+
+ if (j == 0)
+ {
+ /* It must have a function pointer. It must be enabled, or we
+ must have explicitly allowed disabled functions to be found,
+ and it must not have been deleted. */
+ if (shell_builtins[mid].function &&
+ ((shell_builtins[mid].flags & BUILTIN_DELETED) == 0) &&
+ ((shell_builtins[mid].flags & BUILTIN_ENABLED) || disabled_okay))
+ return (&shell_builtins[mid]);
+ else
+ return ((struct builtin *)NULL);
+ }
+ if (j > 0)
+ hi = mid - 1;
+ else
+ lo = mid + 1;
+ }
+ return ((struct builtin *)NULL);
+}
+
+/* Return the pointer to the function implementing builtin command NAME. */
+sh_builtin_func_t *
+find_shell_builtin (name)
+ char *name;
+{
+ current_builtin = builtin_address_internal (name, 0);
+ return (current_builtin ? current_builtin->function : (sh_builtin_func_t *)NULL);
+}
+
+/* Return the address of builtin with NAME, whether it is enabled or not. */
+sh_builtin_func_t *
+builtin_address (name)
+ char *name;
+{
+ current_builtin = builtin_address_internal (name, 1);
+ return (current_builtin ? current_builtin->function : (sh_builtin_func_t *)NULL);
+}
+
+/* Return the function implementing the builtin NAME, but only if it is a
+ POSIX.2 special builtin. */
+sh_builtin_func_t *
+find_special_builtin (name)
+ char *name;
+{
+ current_builtin = builtin_address_internal (name, 0);
+ return ((current_builtin && (current_builtin->flags & SPECIAL_BUILTIN)) ?
+ current_builtin->function :
+ (sh_builtin_func_t *)NULL);
+}
+
+static int
+shell_builtin_compare (sbp1, sbp2)
+ struct builtin *sbp1, *sbp2;
+{
+ int result;
+
+ if ((result = sbp1->name[0] - sbp2->name[0]) == 0)
+ result = strcmp (sbp1->name, sbp2->name);
+
+ return (result);
+}
+
+/* Sort the table of shell builtins so that the binary search will work
+ in find_shell_builtin. */
+void
+initialize_shell_builtins ()
+{
+ qsort (shell_builtins, num_shell_builtins, sizeof (struct builtin),
+ (QSFUNC *)shell_builtin_compare);
+}
+
+#if !defined (HELP_BUILTIN)
+void
+builtin_help ()
+{
+ printf ("%s: %s\n", this_command_name, _("help not available in this version"));
+}
+#endif