Adding upstream version 5.0.upstream/5.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 705 insertions, 0 deletions

diff --git a/builtins/evalstring.c b/builtins/evalstring.c
new file mode 100644
index 0000000..1496eee
--- /dev/null
+++ b/builtins/evalstring.c
@@ -0,0 +1,705 @@
+/* evalstring.c - evaluate a string as one or more shell commands. */
+
+/* Copyright (C) 1996-2017 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 <signal.h>
+
+#include <errno.h>
+
+#include "filecntl.h"
+#include "../bashansi.h"
+
+#include "../shell.h"
+#include "../jobs.h"
+#include "../builtins.h"
+#include "../flags.h"
+#include "../parser.h"
+#include "../input.h"
+#include "../execute_cmd.h"
+#include "../redir.h"
+#include "../trap.h"
+#include "../bashintl.h"
+
+#include <y.tab.h>
+
+#if defined (HISTORY)
+#  include "../bashhist.h"
+#endif
+
+#include "common.h"
+#include "builtext.h"
+
+#if !defined (errno)
+extern int errno;
+#endif
+
+#define IS_BUILTIN(s)	(builtin_address_internal(s, 0) != (struct builtin *)NULL)
+
+int parse_and_execute_level = 0;
+
+static int cat_file __P((REDIRECT *));
+
+#define PE_TAG "parse_and_execute top"
+#define PS_TAG "parse_string top"
+
+#if defined (HISTORY)
+static void
+set_history_remembering ()
+{
+  remember_on_history = enable_history_list;
+}
+#endif
+
+static void
+restore_lastcom (x)
+     char *x;
+{
+  FREE (the_printed_command_except_trap);
+  the_printed_command_except_trap = x;
+}
+
+int
+should_suppress_fork (command)
+     COMMAND *command;
+{
+  return (startup_state == 2 && parse_and_execute_level == 1 &&
+	  running_trap == 0 &&
+	  *bash_input.location.string == '\0' &&
+	  command->type == cm_simple &&
+	  signal_is_trapped (EXIT_TRAP) == 0 &&
+	  signal_is_trapped (ERROR_TRAP) == 0 &&
+	  any_signals_trapped () < 0 &&
+	  command->redirects == 0 && command->value.Simple->redirects == 0 &&
+	  ((command->flags & CMD_TIME_PIPELINE) == 0) &&
+	  ((command->flags & CMD_INVERT_RETURN) == 0));
+}
+
+void
+optimize_fork (command)
+     COMMAND *command;
+{
+  if (command->type == cm_connection &&
+      (command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR) &&
+      should_suppress_fork (command->value.Connection->second))
+    {
+      command->value.Connection->second->flags |= CMD_NO_FORK;
+      command->value.Connection->second->value.Simple->flags |= CMD_NO_FORK;
+    }
+}
+
+void
+optimize_subshell_command (command)
+     COMMAND *command;
+{
+  if (running_trap == 0 &&
+      command->type == cm_simple &&
+      signal_is_trapped (EXIT_TRAP) == 0 &&
+      signal_is_trapped (ERROR_TRAP) == 0 &&
+      any_signals_trapped () < 0 &&
+      command->redirects == 0 && command->value.Simple->redirects == 0 &&
+      ((command->flags & CMD_TIME_PIPELINE) == 0) &&
+      ((command->flags & CMD_INVERT_RETURN) == 0))
+    {
+      command->flags |= CMD_NO_FORK;
+      command->value.Simple->flags |= CMD_NO_FORK;
+    }
+  else if (command->type == cm_connection &&
+	   (command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR))
+    optimize_subshell_command (command->value.Connection->second);
+}
+     
+/* How to force parse_and_execute () to clean up after itself. */
+void
+parse_and_execute_cleanup (old_running_trap)
+     int old_running_trap;
+{
+  if (running_trap > 0)
+    {
+      /* We assume if we have a different value for running_trap than when
+	 we started (the only caller that cares is evalstring()), the
+	 original caller will perform the cleanup, and we should not step
+	 on them. */
+      if (running_trap != old_running_trap)
+	run_trap_cleanup (running_trap - 1);
+      unfreeze_jobs_list ();
+    }
+
+  if (have_unwind_protects ())
+     run_unwind_frame (PE_TAG);
+  else
+    parse_and_execute_level = 0;			/* XXX */
+}
+
+static void
+parse_prologue (string, flags, tag)
+     char *string;
+     int flags;
+     char *tag;
+{
+  char *orig_string, *lastcom;
+  int x;
+
+  orig_string = string;
+  /* Unwind protect this invocation of parse_and_execute (). */
+  begin_unwind_frame (tag);
+  unwind_protect_int (parse_and_execute_level);
+  unwind_protect_jmp_buf (top_level);
+  unwind_protect_int (indirection_level);
+  unwind_protect_int (line_number);
+  unwind_protect_int (line_number_for_err_trap);
+  unwind_protect_int (loop_level);
+  unwind_protect_int (executing_list);
+  unwind_protect_int (comsub_ignore_return);
+  if (flags & (SEVAL_NONINT|SEVAL_INTERACT))
+    unwind_protect_int (interactive);
+
+#if defined (HISTORY)
+  if (parse_and_execute_level == 0)
+    add_unwind_protect (set_history_remembering, (char *)NULL);
+  else
+    unwind_protect_int (remember_on_history);	/* can be used in scripts */
+#  if defined (BANG_HISTORY)
+  unwind_protect_int (history_expansion_inhibited);
+#  endif /* BANG_HISTORY */
+#endif /* HISTORY */
+
+  if (interactive_shell)
+    {
+      x = get_current_prompt_level ();
+      add_unwind_protect (set_current_prompt_level, x);
+    }
+
+  if (the_printed_command_except_trap)
+    {
+      lastcom = savestring (the_printed_command_except_trap);
+      add_unwind_protect (restore_lastcom, lastcom);
+    }
+
+  add_unwind_protect (pop_stream, (char *)NULL);
+  if (parser_expanding_alias ())
+    add_unwind_protect (parser_restore_alias, (char *)NULL);
+
+  if (orig_string && ((flags & SEVAL_NOFREE) == 0))
+    add_unwind_protect (xfree, orig_string);
+  end_unwind_frame ();
+
+  if (flags & (SEVAL_NONINT|SEVAL_INTERACT))
+    interactive = (flags & SEVAL_NONINT) ? 0 : 1;
+
+#if defined (HISTORY)
+  if (flags & SEVAL_NOHIST)
+    bash_history_disable ();
+#  if defined (BANG_HISTORY)
+  if (flags & SEVAL_NOHISTEXP)
+    history_expansion_inhibited = 1;
+#  endif /* BANG_HISTORY */
+#endif /* HISTORY */
+}
+
+/* Parse and execute the commands in STRING.  Returns whatever
+   execute_command () returns.  This frees STRING.  FLAGS is a
+   flags word; look in common.h for the possible values.  Actions
+   are:
+   	(flags & SEVAL_NONINT) -> interactive = 0;
+   	(flags & SEVAL_INTERACT) -> interactive = 1;
+   	(flags & SEVAL_NOHIST) -> call bash_history_disable ()
+   	(flags & SEVAL_NOFREE) -> don't free STRING when finished
+   	(flags & SEVAL_RESETLINE) -> reset line_number to 1
+   	(flags & SEVAL_NOHISTEXP) -> history_expansion_inhibited -> 1
+*/
+
+int
+parse_and_execute (string, from_file, flags)
+     char *string;
+     const char *from_file;
+     int flags;
+{
+  int code, lreset;
+  volatile int should_jump_to_top_level, last_result;
+  COMMAND *volatile command;
+  volatile sigset_t pe_sigmask;
+
+  parse_prologue (string, flags, PE_TAG);
+
+  parse_and_execute_level++;
+
+  lreset = flags & SEVAL_RESETLINE;
+
+#if defined (HAVE_POSIX_SIGNALS)
+  /* If we longjmp and are going to go on, use this to restore signal mask */
+  sigemptyset ((sigset_t *)&pe_sigmask);
+  sigprocmask (SIG_BLOCK, (sigset_t *)NULL, (sigset_t *)&pe_sigmask);
+#endif
+
+  /* Reset the line number if the caller wants us to.  If we don't reset the
+     line number, we have to subtract one, because we will add one just
+     before executing the next command (resetting the line number sets it to
+     0; the first line number is 1). */
+  push_stream (lreset);
+  if (parser_expanding_alias ())
+    /* push current shell_input_line */
+    parser_save_alias ();
+  
+  if (lreset == 0)
+    line_number--;
+    
+  indirection_level++;
+
+  code = should_jump_to_top_level = 0;
+  last_result = EXECUTION_SUCCESS;
+
+  /* We need to reset enough of the token state so we can start fresh. */
+  if (current_token == yacc_EOF)
+    current_token = '\n';		/* reset_parser() ? */
+
+  with_input_from_string (string, from_file);
+  clear_shell_input_line ();
+  while (*(bash_input.location.string))
+    {
+      command = (COMMAND *)NULL;
+
+      if (interrupt_state)
+	{
+	  last_result = EXECUTION_FAILURE;
+	  break;
+	}
+
+      /* Provide a location for functions which `longjmp (top_level)' to
+	 jump to.  This prevents errors in substitution from restarting
+	 the reader loop directly, for example. */
+      code = setjmp_nosigs (top_level);
+
+      if (code)
+	{
+	  should_jump_to_top_level = 0;
+	  switch (code)
+	    {
+	    case ERREXIT:
+	      /* variable_context -> 0 is what eval.c:reader_loop() does in
+		 these circumstances.  Don't bother with cleanup here because
+		 we don't want to run the function execution cleanup stuff
+		 that will cause pop_context and other functions to run.
+		 XXX - change that if we want the function context to be
+		 unwound. */
+	      if (exit_immediately_on_error && variable_context)
+	        {
+	          discard_unwind_frame ("pe_dispose");
+		  variable_context = 0;	/* not in a function */
+	        }
+	      should_jump_to_top_level = 1;
+	      goto out;
+	    case FORCE_EOF:	      
+	    case EXITPROG:
+	      if (command)
+		run_unwind_frame ("pe_dispose");
+	      /* Remember to call longjmp (top_level) after the old
+		 value for it is restored. */
+	      should_jump_to_top_level = 1;
+	      goto out;
+
+	    case DISCARD:
+	      if (command)
+		run_unwind_frame ("pe_dispose");
+	      last_result = last_command_exit_value = EXECUTION_FAILURE; /* XXX */
+	      if (subshell_environment)
+		{
+		  should_jump_to_top_level = 1;
+		  goto out;
+		}
+	      else
+		{
+#if 0
+		  dispose_command (command);	/* pe_dispose does this */
+#endif
+#if defined (HAVE_POSIX_SIGNALS)
+		  sigprocmask (SIG_SETMASK, (sigset_t *)&pe_sigmask, (sigset_t *)NULL);
+#endif
+		  continue;
+		}
+
+	    default:
+	      command_error ("parse_and_execute", CMDERR_BADJUMP, code, 0);
+	      break;
+	    }
+	}
+	  
+      if (parse_command () == 0)
+	{
+	  if ((flags & SEVAL_PARSEONLY) || (interactive_shell == 0 && read_but_dont_execute))
+	    {
+	      last_result = EXECUTION_SUCCESS;
+	      dispose_command (global_command);
+	      global_command = (COMMAND *)NULL;
+	    }
+	  else if (command = global_command)
+	    {
+	      struct fd_bitmap *bitmap;
+
+	      if (flags & SEVAL_FUNCDEF)
+		{
+		  char *x;
+
+		  /* If the command parses to something other than a straight
+		     function definition, or if we have not consumed the entire
+		     string, or if the parser has transformed the function
+		     name (as parsing will if it begins or ends with shell
+		     whitespace, for example), reject the attempt */
+		  if (command->type != cm_function_def ||
+		      ((x = parser_remaining_input ()) && *x) ||
+		      (STREQ (from_file, command->value.Function_def->name->word) == 0))
+		    {
+		      internal_warning (_("%s: ignoring function definition attempt"), from_file);
+		      should_jump_to_top_level = 0;
+		      last_result = last_command_exit_value = EX_BADUSAGE;
+		      reset_parser ();
+		      break;
+		    }
+		}
+
+	      bitmap = new_fd_bitmap (FD_BITMAP_SIZE);
+	      begin_unwind_frame ("pe_dispose");
+	      add_unwind_protect (dispose_fd_bitmap, bitmap);
+	      add_unwind_protect (dispose_command, command);	/* XXX */
+
+	      global_command = (COMMAND *)NULL;
+
+	      if ((subshell_environment & SUBSHELL_COMSUB) && comsub_ignore_return)
+		command->flags |= CMD_IGNORE_RETURN;
+
+#if defined (ONESHOT)
+	      /*
+	       * IF
+	       *   we were invoked as `bash -c' (startup_state == 2) AND
+	       *   parse_and_execute has not been called recursively AND
+	       *   we're not running a trap AND
+	       *   we have parsed the full command (string == '\0') AND
+	       *   we're not going to run the exit trap AND
+	       *   we have a simple command without redirections AND
+	       *   the command is not being timed AND
+	       *   the command's return status is not being inverted AND
+	       *   there aren't any traps in effect
+	       * THEN
+	       *   tell the execution code that we don't need to fork
+	       */
+	      if (should_suppress_fork (command))
+		{
+		  command->flags |= CMD_NO_FORK;
+		  command->value.Simple->flags |= CMD_NO_FORK;
+		}
+	      else if (command->type == cm_connection)
+		optimize_fork (command);
+#endif /* ONESHOT */
+
+	      /* See if this is a candidate for $( <file ). */
+	      if (startup_state == 2 &&
+		  (subshell_environment & SUBSHELL_COMSUB) &&
+		  *bash_input.location.string == '\0' &&
+		  command->type == cm_simple && !command->redirects &&
+		  (command->flags & CMD_TIME_PIPELINE) == 0 &&
+		  command->value.Simple->words == 0 &&
+		  command->value.Simple->redirects &&
+		  command->value.Simple->redirects->next == 0 &&
+		  command->value.Simple->redirects->instruction == r_input_direction &&
+		  command->value.Simple->redirects->redirector.dest == 0)
+		{
+		  int r;
+		  r = cat_file (command->value.Simple->redirects);
+		  last_result = (r < 0) ? EXECUTION_FAILURE : EXECUTION_SUCCESS;
+		}
+	      else
+		last_result = execute_command_internal
+				(command, 0, NO_PIPE, NO_PIPE, bitmap);
+	      dispose_command (command);
+	      dispose_fd_bitmap (bitmap);
+	      discard_unwind_frame ("pe_dispose");
+
+	      if (flags & SEVAL_ONECMD)
+		{
+		  reset_parser ();
+		  break;
+		}
+	    }
+	}
+      else
+	{
+	  last_result = EX_BADUSAGE;	/* was EXECUTION_FAILURE */
+
+	  if (interactive_shell == 0 && this_shell_builtin &&
+	      (this_shell_builtin == source_builtin || this_shell_builtin == eval_builtin) &&
+	      last_command_exit_value == EX_BADSYNTAX && posixly_correct && executing_command_builtin == 0)
+	    {
+	      should_jump_to_top_level = 1;
+	      code = ERREXIT;
+	      last_command_exit_value = EX_BADUSAGE;
+	    }
+
+	  /* Since we are shell compatible, syntax errors in a script
+	     abort the execution of the script.  Right? */
+	  break;
+	}
+    }
+
+ out:
+
+  run_unwind_frame (PE_TAG);
+
+  if (interrupt_state && parse_and_execute_level == 0)
+    {
+      /* An interrupt during non-interactive execution in an
+	 interactive shell (e.g. via $PROMPT_COMMAND) should
+	 not cause the shell to exit. */
+      interactive = interactive_shell;
+      throw_to_top_level ();
+    }
+
+  if (should_jump_to_top_level)
+    jump_to_top_level (code);
+
+  return (last_result);
+}
+
+/* Parse a command contained in STRING according to FLAGS and return the
+   number of characters consumed from the string.  If non-NULL, set *ENDP
+   to the position in the string where the parse ended.  Used to validate
+   command substitutions during parsing to obey Posix rules about finding
+   the end of the command and balancing parens. */
+int
+parse_string (string, from_file, flags, endp)
+     char *string;
+     const char *from_file;
+     int flags;
+     char **endp;
+{
+  int code, nc;
+  volatile int should_jump_to_top_level;
+  COMMAND *volatile command, *oglobal;
+  char *ostring;
+  volatile sigset_t ps_sigmask;
+
+  parse_prologue (string, flags, PS_TAG);
+
+#if defined (HAVE_POSIX_SIGNALS)
+  /* If we longjmp and are going to go on, use this to restore signal mask */
+  sigemptyset ((sigset_t *)&ps_sigmask);
+  sigprocmask (SIG_BLOCK, (sigset_t *)NULL, (sigset_t *)&ps_sigmask);
+#endif
+
+/*itrace("parse_string: `%s'", string);*/
+  /* Reset the line number if the caller wants us to.  If we don't reset the
+     line number, we have to subtract one, because we will add one just
+     before executing the next command (resetting the line number sets it to
+     0; the first line number is 1). */
+  push_stream (0);
+  if (parser_expanding_alias ())
+    /* push current shell_input_line */
+    parser_save_alias ();
+
+  code = should_jump_to_top_level = 0;
+  oglobal = global_command;
+  ostring = string;
+
+  with_input_from_string (string, from_file);
+  while (*(bash_input.location.string))
+    {
+      command = (COMMAND *)NULL;
+
+#if 0
+      if (interrupt_state)
+	break;
+#endif
+
+      /* Provide a location for functions which `longjmp (top_level)' to
+	 jump to. */
+      code = setjmp_nosigs (top_level);
+
+      if (code)
+	{
+#if defined (DEBUG)
+itrace("parse_string: longjmp executed: code = %d", code);
+#endif
+	  should_jump_to_top_level = 0;
+	  switch (code)
+	    {
+	    case FORCE_EOF:
+	    case ERREXIT:
+	    case EXITPROG:
+	    case DISCARD:		/* XXX */
+	      if (command)
+		dispose_command (command);
+	      /* Remember to call longjmp (top_level) after the old
+		 value for it is restored. */
+	      should_jump_to_top_level = 1;
+	      goto out;
+
+	    default:
+#if defined (HAVE_POSIX_SIGNALS)
+	      sigprocmask (SIG_SETMASK, (sigset_t *)&ps_sigmask, (sigset_t *)NULL);
+#endif
+	      command_error ("parse_string", CMDERR_BADJUMP, code, 0);
+	      break;
+	    }
+	}
+	  
+      if (parse_command () == 0)
+	{
+	  dispose_command (global_command);
+	  global_command = (COMMAND *)NULL;
+	}
+      else
+	{
+	  if ((flags & SEVAL_NOLONGJMP) == 0)
+	    {
+	      should_jump_to_top_level = 1;
+	      code = DISCARD;
+	    }
+	  else
+	    reset_parser ();	/* XXX - sets token_to_read */
+	  break;
+	}
+
+      if (current_token == yacc_EOF || current_token == shell_eof_token)
+	  break;
+    }
+
+ out:
+
+  global_command = oglobal;
+  nc = bash_input.location.string - ostring;
+  if (endp)
+    *endp = bash_input.location.string;
+
+  run_unwind_frame (PS_TAG);
+
+  /* If we return < 0, the caller (xparse_dolparen) will jump_to_top_level for
+     us, after doing cleanup */
+  if (should_jump_to_top_level)
+    {
+      if (parse_and_execute_level == 0)
+	top_level_cleanup ();
+      if (code == DISCARD)
+	return -DISCARD;
+      jump_to_top_level (code);
+    }
+
+  return (nc);
+}
+
+/* Handle a $( < file ) command substitution.  This expands the filename,
+   returning errors as appropriate, then just cats the file to the standard
+   output. */
+static int
+cat_file (r)
+     REDIRECT *r;
+{
+  char *fn;
+  int fd, rval;
+
+  if (r->instruction != r_input_direction)
+    return -1;
+
+  /* Get the filename. */
+  if (posixly_correct && !interactive_shell)
+    disallow_filename_globbing++;
+  fn = redirection_expand (r->redirectee.filename);
+  if (posixly_correct && !interactive_shell)
+    disallow_filename_globbing--;
+
+  if (fn == 0)
+    {
+      redirection_error (r, AMBIGUOUS_REDIRECT);
+      return -1;
+    }
+
+  fd = open(fn, O_RDONLY);
+  if (fd < 0)
+    {
+      file_error (fn);
+      free (fn);
+      return -1;
+    }
+
+  rval = zcatfd (fd, 1, fn);
+
+  free (fn);
+  close (fd);
+
+  return (rval);
+}
+
+int
+evalstring (string, from_file, flags)
+     char *string;
+     const char *from_file;
+     int flags;
+{
+  volatile int r, rflag, rcatch;
+  volatile int was_trap;
+
+  /* Are we running a trap when we execute this function? */
+  was_trap = running_trap;
+
+  rcatch = 0;
+  rflag = return_catch_flag;
+  /* If we are in a place where `return' is valid, we have to catch
+     `eval "... return"' and make sure parse_and_execute cleans up. Then
+     we can trampoline to the previous saved return_catch location. */
+  if (rflag)
+    {
+      begin_unwind_frame ("evalstring");
+
+      unwind_protect_int (return_catch_flag);
+      unwind_protect_jmp_buf (return_catch);
+
+      return_catch_flag++;	/* increment so we have a counter */
+      rcatch = setjmp_nosigs (return_catch);
+    }
+
+  if (rcatch)
+    {
+      /* We care about whether or not we are running the same trap we were
+	 when we entered this function. */
+      parse_and_execute_cleanup (was_trap);
+      r = return_catch_value;
+    }
+  else
+    /* Note that parse_and_execute () frees the string it is passed. */
+    r = parse_and_execute (string, from_file, flags);
+
+  if (rflag)
+    {
+      run_unwind_frame ("evalstring");
+      if (rcatch && return_catch_flag)
+	{
+	  return_catch_value = r;
+	  sh_longjmp (return_catch, 1);
+	}
+    }
+    
+  return (r);
+}